Trease and Evans Pharmacognosy

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Contents Preface ix

11. Plantcell andtissueculture;biological conversions; clonalpropagation j2

Contributors xi

12. Phytochemicalvariationwithin a species 80 Pqrt I Introducfion

13. Deteriorationof storeddrugs 9l I

l. Plantsin medicine:the originsof pharmacognosy 3 2. The scopeandpracticeof pharmacognosy 5 3. Plant nomenclatureand taxonomv 8 Pqrl2 The plont qnd onimql kingdoms os

sourcesof drugs

ll

4. Biologicalandgeographical sourcesof drugs 13 5. A taxonomicapproachto the studyof medicinalplantsandanimal-derived drugs 15 6. Pharmacologicalactivitiesof natural products 4I 7. Synergyin relationto the pharmacological actionof phytomedicinals 49 E. M. Williamszn

14. Quality control 95 Pqrt 4 Some currenl frends

107

15. Plant productsand High Throughput Screening 109 M. J. O'Neill, J. A. Lewis 16. Biologically activecompoundsfrom marine organisms 115 G. Blttnden 17. Traditionalplant medicinesas a sourceof new drugs 125 P. J. Houghton Pqrt 5

Phyrochemisrry 135 18. Generalmethodsassociatedwith the phytochemicalinvestigationof herbal products 137 19. Basicmetabolicpathwaysandthe origin of secondarymetabolites150

Port 3 Pqrt 6 Principlesrelqted to the commerciqt qnd relqted drugs of Phqrmqcopoeiol production, quolity qnd stqndqrdizqtion biologicol origin l7l of nolurql products 55 Introduction 173

8. Commercein crudedruss 5i R. Baker

20. Hydrocarbonsand derivatives 174

9. Productionofcrude drugs 6l

21. Carbohydrates 191

10. Plantgrowthregulators 6l

22. Phenolsand phenolicglycosides 214

Id..:e6Nif 23. Volatile oils and resins 253 24. Saponins,cardioactivedrugsand other steroids 289 25. Miscellaneousisoprenoids 315 26. Cy anageneticglycosides,glucosinolate compoundsand miscellaneous glycosides 321 27. Alkaloids

37. Aspectsof Asian medicineand its practicern the West 461 M. Aslam

38. Chineseherbsin the West 482 S. Y.Mills

39. Plantsin African traditional medicine-an overview 488 A. Sofowora

333

28. Tumour inhibitors from plants 394 P. M. Dewick 29. Antiprotozoalnatural products 401 C. W. Wright 30. An overview of drugs with antihepatotoxic and oral hypoglycaemic activities 414

Port 8 Nonmedicinol toxic plonts ond pesticides 497 40. Hallucinogenic, allergenic,teratogenicand other toxic plants 499 4L. Pesticidesof naturalorigin

509

3L. Vitamins and hormones 42I

33. Colouringandflavouringagents 435

Pcrrt9 Morphologicol qnd microscoPicql exqminqtion of drugs 513

34. Miscellaneousproducts 440

I n t r o d u c t i o n5 1 5

32. Antibacterial and antiviral drugs 429

Porl7 Plqnts in complementqry ond troditionql syslems of medicine 445 Introduction 441 35. Herbal medicine in Britain and Europe: regulation and practice 449 S. Y.Mills 36. Homoeopathicmedicine and aromatherapy 460 M. A. Healy, M. Aslam

42. Plant description,morphology and anatomy 516 43. Cell differentiation and ergasticcell contents 526 44. Techntquesin microscoPY 538 Index

549

E

Plonts in medicine: theorigins of phormocognosy

The universal role of plants in the treatment of diseaseis exemplified by their employment in all the major systemsof medicine irrespective of the underlying philosophical premise. As examples, we have Western medicine with origins in Mesopotamia and Egypt, the Unani (Islamic) and Ayurvedic (Hindu) systemscentred in western Asia and the Indian subcontinent and those of the Orient (China, Japan,Tibet, etc.). How and when such medicinal plants were first used is, in many cases, lost in pre-history, indeed animals, other than man, appear to have their own materia medica. Following the oral transmission of medical information came the use of writing (e.g. the Egyptian Papyrus Ebers c.1600 nc), baked clay tablets(some 660 cuneiform tablets c. 650 ec from Ashurbanipal's library at Nineveh, now in the British Museum, refer to drugs well-known today), parchments and manuscript herbals, printed herbals (invention of printing l44O AD), pharmacopoeias and other works of reference (ftrst London Pharmacopoeia, 1618; first British Pharmacopoeia 1864), and most recently electronic storage of data. Similar records exist for Chinese medicinal plants (texts from the 4th century ec), Ayurvedic medicine (Ayurveda 2500-600 nc) and Unani medicine (Kitab-Al-ShiJa, rhe Magnum Opus of Avicenna,980-1037 ao). In addition to the above recorded information there is a great wealth of knowledge concerning the medicinal, narcotic and other properties ofplants that is still ffansmitted orally from generationto generationby tribal societies,particularly those of tropical Africa, North and South America and the Pacific countries. These are areas containing the world's greatest number of plant species, not found elsewhere, and with the westernization of so many of the peoples of these zones there is a pressing needto record local knowledge before it is lost forever. In addition, with the extermination of plant species progressing at an alarming rate in certain regions, even before plants have been botanically recorded, much less studied chemically and pharmacologically, the need arises for increasedefforts directed towards the conservation of genepools. A complete understandingof medicinal plants involves a number of disciplinesincluding commerce,botany,horticulture, chemistry enzymology, genetics, quality control and pharmacology.Pharmacognosyis not any one of theseper sebut seeksto embracethem in a unified whole for the betterunderstandingand utilization of medicinal plants.Aperusal ofthe monographson crude drugs in a modem pharmacopoeiaat once illusfates the necessityfor a multidisciplinary approach.Unlike those who laid the foundations of pharmacognosy,no one person can now expectto be an expert in all areasand, asis illustratedin the next chapter, pharmacognosycan be independently approachedfrom a number of viewpoints. The word 'pharmacognosy'had its debut in the early 19th century to designatethe discipline related to medicinal plants; it is derived from the Greek pharmakon, 'a drug', and gignosco, 'to acquire a knowledge of' and, as recordedby Dr K. Ganzinger(Sci. Pharm.1982, 50, 351), the terms 'pharmacognosy' and 'pharmacodynamics' were probably first coined by JohannAdam Schmidt (1759-1809) in his hand-written manuscript Lehrbuch der Materia Medica, which was posthumously published in Vienna in 18I 1. Schmidt was, unril his death,professor at the medico-surgical JosephAcademy in Vienna; interestingly he was also Beethoven's physician. Shortly after the above publication, 'pharrnacognosy' appears again in 1815 in a small work by Chr. Aenotheus Seydler entitled Analecta Pharmacognostica. Pharmacognosyis closely related to botany and plant chemistry and, indeed, both originated from the eartier scientific studieson medicinal plants. As late as the beginning of the 20th century, the subject had developed mainly on the botanical side, being concemed with the description and identification of drugs, both in the whole state and in powdeq and with their history, commerce, collection, preparation and

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storage. Such branches of pharmacognosy are still of fundamental importance, particularly for pharmacopoeialidentification and quality control purposes, but rapid developments in other areas have enormously expandedthe subject. The use of modern isolation techniquesand pharmacologicaitesting proceduresmeansthat new plant drugs usually find their way into medicine as purified substancesrather than in the fbrm of galenical preparations.Preparationis usually confined to one or a few companieswho process all the raw material; thus, few pharmacists have occasion to handle dried Catharanthus roseils although they are familiar with formulations ofthe isolated alkaloids vinblastine and vincristine. For these new drugs it is important that the pharmacist, rather than being fully conversant with the macroscopical and histological charactersof the dried plant, is able to cary out the chromatographic and other proceduresnecessaryfor the identification and determination of purity of the preparation supplied. Similar remarks apply to such drugs as Rauwolfia, the modem preparationsof ergot, and the cardioactive and purgative drugs. When specific plants,including thoseusedin traditional medicine, suddenly become of interest to the world at large, the local wild sourcessoon become exhausted.This necessitates,as in the caseof Catharanthusroseus,Coleus forskohlii, Arnica montana and Taxus brevfolia, research into the cultivation or a.rtificial propagation by cell culture, etc., of such species.In order to avert the type of supply crisis that arose at the clinical trial stage with the anticancer drug taxol, isolated from 7. brevfolia, the US National Cancer Institute has initiated plans for future action when a similar situation again arises (see G. M. Cragg et al., J. Nat. Prod., 1993, 56, 165'7).

However, it has been repofied that as a result of demandfor the new drug galanthamine(qv) for the treatmentof Alzheimer's disease,the native sourceof Leucojum aestivumis now in danger. The use of single pure compounds,including synthetic drugs, is not without its limitations, and in recent years there has been an immenserevival in interestin the herbal and homoeopathicsystems of medicine, both of which rely heavily on plant sources,At the 9th Congress of the Italian Society of Pharmacognosy(1998) it was stated that the current return of phytotherapy was clearly reflected by the increased market of such products. In 1995 the latter, for Europe, reached a figure of $6 billion, with consumption for Germany $2.5 billion, France $1.6 billion and ltaly 600 million. In the US, where the use ofherbal products has never been as strong as in continental Europe, the increase in recent years has also been unprecedentedwith the market for all herb salesreaching a peak in 1998 approaching$700 million. Again, illustrating the same trend, the editor of Journal of Natural Products, 1999, writes that in response to the increasing prominence of herbal remedies, additional contributions describingscientific investigationsof a rigorous nature are welcomed. Undoubtedly, the plant kingdom still holds many speciesof plants containingsubstances of medicinalvalue which haveyet to be discovered; large numbers of plants are constantly being screenedfor their possiblepharmacological value (particularly for their anti-inflammatory, hypotensive, hypoglycaemic, amoebicidal, anti-fertility, cytotoxic, antibiotic and anti-Parkinsonismproperties). Pharmacognosistswith a multidisciplinary background are able to make valuable contributions to theserapidly developing fields of study.

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Thescopeond proctice of phormocognosy

Until relatively recently pharmacognosywas regarded, almost exclusively, as a subject in the pharmaceuticalcurriculum focused on those natural products employed in the allopathic system of medicine. Coincident with the increasing attractivenessof alternative (complementary) therapies and the tremendous range of herbal products now generally available to the public, regulatory requirements covering medicinal herbs are being introduced by many countries in order to control the quality ofthese products.Monographs are now available on a large number of such drugs giving descriptions,testsfor identity and purity and assaysof active constituents.These monographs are being compiled by a number of bodies (see below). In this respect recognition should be given to the pioneering production ofthe Brirlsh Herbal Pharmacopoeia, first produced in 1974with subsequenteditions, and a new one pending. Pharmacognosyis also important in those countries having their own systems of medicine in which plants are important components. Although pharmacognosyis principally concernedwith plant materials, there are a small number of animal products which are traditionally encompassedwithin the subject; these include such items as beeswax,gelatin, woolfat, vitamins, etc. Other natural products such as the antibiotics, hormones and others may or may not be involved, depending on the teaching practice of a particular institution. As is shown in Chapter 16 m4rine organisms,many of the animal kingdom, are receiving increasing attention. Materials having no pharmacological action which are of interest to pharmacognosistsare natural fibres, flavouring and suspendingagents,colourants,disintegrants,stabilizers and filtering and support media. Other areasthat have natural associations with the subject are poisonous and hallucinogenic plants, allergens,herbicides,insecticidesand yrolluscicides. Vegetabledrugs can be arrangetlfor study under the following headings.

t . Alphabetical. Either Latin or vernacular names may be used. This arrangement is employed fol dictionaries, pharmacopoeias, etc. Although suitable for quick referenceit gives no indication ofinterrelationshipsbetween drugs. 2. Taxonomic.On the basis ofan acceptedsystemofbotanical classification (Chapter 3), the drugs are arranged according to the plants from which they are obtained, in classes,orders, families, genera and species.It allows for a precise and ordered arrangement and accommodatesany drug without ambiguity. As the basic botanical knowledge of pharmacy studentsdecreasesover the years this system is becoming less popular for teaching purposes. Morphological. The drugs are divided into groups such as the following: leaves, flowers, fruits, seeds,herbs and entire organisms, woods, barks, rhizomes and roots (known as organized drugs), and dried latices, extracts, gums, resins, oils, fats and waxes (unorganized drugs). These groupings have some advantagesfor the practical study of crude drugs; the identification of powdered drugs (see Chapter 44) is often basedon micro-morphological characters. 4 . Pharmacological or Therapeutic. This classification involves the grouping of drugs according to the pharmacological action of their most important constituent or their therapeutic use. R. Pratt and H. W. Youngken Jr. were, in 1956, the first to use this approach for an English languagetextbook and now, with so many plant materials being screenedfor specific pharmacological activity, this type of listing is found increasingly in the literature. Its use is illustrated in Chapters28-32.However, it is important to appreciatethat the constituents of any one drug may fall into different pharmacological groups. Chemical or Biogenetic. The important constituents,e.g. alkaloids, glycosides, volatile oils, etc., or their biosynthetic pathways, form

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Thescopeond proctice of phormocognosy

Until relatively recently pharmacognosywas regarded,almost exclusively, as a subjectin the pharmaceuticalcumiculumfocusedon those natural products employed in the allopathic system of medicine. Coincident with the increasingattractivenessof alternative(complementary)therapiesand the tremendousrange of herbal productsnow generally available to the public, regulatory requirementscovering medicinal herbs are being introducedby many countries in order to controlthe quality o1'theseproducts.Monographsarenow availablcon a largenurnberof suchdrugsgiving descriptions,testsfor identity and purity and assaysof active constituents.Thesemonographsare being compiled by a number of bodies(seebelow). In this respectrecognition shouldbe given to the pioneeringproductionof theBriti,shHerbal Phormacopoeia,first producedin 1974with subsequent editions,and a new one pending.Pharmacognosyis also importantin thosecountries having their own systemsof medicine in which plants are important components. Although pharmacognosyis principally concemedwith planrmaterials, there are a small number of animal productswhich are traditionally encompassedwithin the subject; these include such items as beeswax,gelatin,woolfat. vitamins,etc.Othernaturalproductssuchas the antibiotics, hormones and others may or may not be involved, dependingon the teaching practice of a particular institution.As is shown in Chapter l6 marine organisms,many of the animal kingdorn, are receiving increasingattention.Materials having no pharmacological actionwhich are of interestto pharmacognosists are natr.rral fibres, llavouring and suspendingagents.colourants.disintegrants,stabilizers ir:r.li" iiiilt;..,,r and filtering and supportmedia.Other areasthat have naturalassocia- ,t:tltiiut:ti : tions with the subjectare poisonousand haliucinogenicplants. aller- ititlu:itau itit.ti]illlrl: gens,herbicides,insecticidesand molluscicides. tit,lri1; Vegetabledrugscan be arrangedfor studyunderthe fbllowing head:tiiril rliiit ings. l . Alphabetical.Either Latin or vernacularnamesmay be used.This

arrangementis employed for dictionaries, pharmacopoeias,etc. Although suitablefbr quick referenceit gives no indicationof interrelationshipsbetweendrugs. Taronomic.On the basisof an acceptedsystemofbotanical classification (Chapter3), the drugs are arrangedaccordingto the plants from which they are obtained,in classes,orders,families, genera and species.It allows for a preciseand ordered arrangementand accommodatesany drug without ambiguity.As the basic botanical knowledgeof pharmacystudentsdecreases over the yearsthis system is becominglesspopuiarfor teachingpurposes. 3 . Morphological. The drugs are divided into groups such as the following: leaves.flowers, fruits, seeds,herbs and entire organisms. woods.barks,rhizomesand roots (known as organizeddrugs).and dried latices,extracts,gums, resins,oi1s,fats and waxes (unorganized drugs).Thesegroupingshave some advantagesfbr the practical study of crude drugs;the identitlcationof powdereddrr.rgs(see Chapterzlzl)is often basedon micro-morphologicalcharacters. 4 . PharmacoktgicaLor Therupeutic.This classificationinvolves the grouping of drugs accordingto the pharmacologicalaction of their most impoftant constituentor their therapeuticuse. R. Pratt and H. W YoungkenJr. were, in 1956.the first to use this approachfor an English languagetextbook and now. with so many plant materials being screenedfbr speciticpharmacologicalactivity.this type of listing is found increasinglyin the literature.Its use is illr-rstrated in Chapters28-32. However,it is importantto appreciatethat the constituentsof any one drug rnay fall into different pharmacological groups. Chemicalor Biogenetic.The importantconstituents,e.g. alkaloids. glycosides.volatile oils, etc., or their biosyntheticpathways.form

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INTRODUCTION As rnentioncdpreviously,a nllrnberof bodieshave implernented the basis of classificationof the drugs.This is a popular approach on ncdicinal herbs.The aint has is phytochernicallybiased. researchand publishednlonogrilphs when the teaching of pl.rarmacognosy Anbiguities alise when particulardrugs possess a numberof active been to sct standardsfix' cluality.etlicacy and sat'etyin order that the principlesbelongingto diflerent phiitochenricalgroups.as illustrat- many tl'aditionalherbs mcct legal requirernents.The follou'ing are of note: ed b1,liquorice.ginseng.r'aleliart.ctc. The sclremeis ernployedin drugs. Chaptels20 27 tbr anangin-tthe cstablishedphartnacopoeial 'I'hese 'nvet'c cleveloped German Commission E monographs. 'I'he *'ill fbllou'ing list of works. arrangedin the abcxe five gror.rps. fbr the Gelrnan FccleralHealth Authoritl' betwccn 1978-1994and andalsoproviclea usefullist oftcxtbooksandt'orks serveascxanrples involr,e32.1herbsused in Gelrnantladitionalmedicine.The monoof reftlence:tlroseno longer in print may be fbund in established graphs give sollrces.constitllentsand considerablcphannacological pharnracer,rticirl liblaries. They havc nou' beentranslatedinto English and clinicalintbrrnation. b1'theArnericiinBotanicalCtiuncilin 1999as tr single and pLrblishcd l. Alphobeticol a handbookfbr practiceon a sciBissetN G (cd). Wichtl N'l 1996Herbal cltr.rgs. u'ork. errtific basis.Meclphanr ScientificPublishcrs,StLtttgat'l r . l i t i s h H c r b a lM c d i c i n e B r a c l l e l ' PR ( e d ) 1 9 9 2B r i t i s hh e r b a lc o n t p c n d i u n B A s s o c i a t i o nB. o u r n e m o u t hU. K Press.London Vols I-II Blitish PhalmacopoeiaI 999. Pharrnaceutical B r i t i s hH c r b a lP h ; r r m a c o p o e1i a9 9 6 .B r i t i s hH e r b a lM e c l i c i n eA s s o c i a t i o t r . Exeter.UK Niartindale:the Extr-aPharmacopoeia.32nd ccln. | 999. PharntaccuticalPress. Londou l999 2-llNationalFornrr-rlary LinitedStatesPhamracopoeia Wren R Cl I988 Potter'sneu'c1'clopocidaol botanrcaldrugs and pfeparations. reuritten b1'WilliamsonE NI and Er'ansF J. C W Daniel Co. Safll'orr \\alden. UK Tl-re national pharmacopocias of niarry countries and the Europeau Pharmacopoeia; the relevant crude drug mono-qraphs of the latter are i r r c l u t l e tilr t t h e B l i t i r h P h r r t n l r c o p o e i r

2. Toxonomic . a r i s . 3r ' o l s . a s s o nP P a l i sR R . N I o l ' s eH 1 9 6 5 .1 9 6 7 .1 9 7I M a t i d r cr n d d i c a l eM ThornasH 1929 Handbuchdet'Phalmacie.Urban and Schu arzcnbcrg.Berlin. Band V 2 r'ols, Phannacogrtosr' . t he d n .B a i l l i i r e T i n d a l la n d T r e a s eG E , E r , a n sW C 1 9 7 2P h a r n a c o g n o s l l' O Casscll.London

3. Morphologicol f, .-1 !

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Mauclt'ich.Vienna.Vol I. Barks and Belger F Hanclbuchder Dt'ogenkunclc. f l o u ' e l s .1 9 . 1 9V: o l I I . L e a r e s .1 9 5 0 :V o l I I I . F f u i t sa n d u ' o o d s ,1 9 5 2 1V o l I V . Vol V. Roots. I 960r Vol Vl. Rcsinsetc and seeds.196.{:Vol Herbs. I 9-5,1: V I I . I n d e x .1 9 6 7 JacksonB P. Snou don D W I 990 Atlas o 1'nticrtrscopl'of nredicinalplants. culinar.vherbsand spices.BelhavenPrcss.l-ondon N'lortonJ F 1977Mixor medicinalplants:botany'.culturc and uses.Thomas. S p l i n g f i e l dI.L . U S A 5th edn. Churchill Livingstone. \\allis T E, I 967 Tertbook of Pharmacognosl'. l"ondon

Coopelativefbr Scier.rtific ESCOPmonographs. ESCOP(European Phytotherapy)is an alllliation of Europeanassociatioltswhich has ploducecl60 monographson helbal clrugs.pttblishedin loose-leaffbrm in six thscicr-rle s. harmonizingthe standaldsfbr thesedrugsthror-rghout thc Er.rlopeanUnion. Intbrrration is given on approved therapcutic uses, ancl unlike the ComrnissionE nono-graphs.plovidcs ref'elerrces. AHP monographs. The American Herbal Pharntacopoeiaplanned by the end of 2000.'nvithsorne30 to havepublishedI l- I 3 t.nonographs of American traditional more pending.Thele is naturally a selectiot-t herbs n'ith somc overlap l''ith thc European monographs.The as trncxamplethe St John'sWort monograph tleatmentis exhaustir,e: rvith ovcr publishedin HelbalGraml99T. No .l extendsto -i2 pa-ees andchemicalfbrmttlae. I50 ref'erences. colourphotographs WHO monographs. The World Health Organization published MerlicirutlPluttts irt 1999.It ttrtSeleL'tetl Volunre I of its MottogrtLplt.s contaiusstandardsfbr clualityof dlr.rgstogethelwith a thelapeuticsccin the tion: 3l plant species.the majcx'ityol u'hich at'ealso inclLrded Vcrlume2. containinga further29 rnonoabovelists.are consiclered. graphs.is cluelbr pLrblicationin 2000. is alsoproducUSPmonographs. The United StatesPharr-nacopocia all involving ing helbnl monographs.Elevcn har"ebeertpr"rblished. drugstteateclabove.and twelve more are expecteclduring 2000.

wishing to read ttliginnl resealchwill Current awareness. Str.rdents in this book and shouldlearnhow to find sin-rilar find rnar-ry ret'erences A, Libcrti t- E I 988 Natural ploduct nredicinc.G F Stickley. Del i\'lalclerosian As no onecanhopeto readall the scientificliteraonesfbl themselves. P h i l a d c l p h i aP. A . U S A specialior.rrnllsare clevotedto the publicationof ture that is pLrblished. PrattR, YoungkenH W. Jr 19-56Pharrlacognosy.2nd edn. Lippincott. P h i l a d e l p h i aP.A . U S A brief abstlacts from the oliginal papers. Such abstractsgive the Ross N4S F. Brain K R 1977An intfoductionto phytopharmacy.Pitnlall author's name.the sub.iectoi the rcscarch.the ref'elencencccssaryto N{edical.Tunbridge\\iells a blief outlineof the locatethe papelin the oliginaljoLrrnalanclusr-rally work it contains. Most phat'nracydepartntentlibraries contain 5. Chemicol phy'tochcrnistry'. medicinarlplants.Intefcept BnrnetonJ 1999Pharnracognos-v. Cltenitul Abstrrr't.r'and Biolo,gital Abstrccls,which in the appropriate Scicntific. N'ledicaland TechnicalPublications EVen st'. the :)':tetrllttr scctionscover all aleasof pharntaco-[nosy. Deu,ick P N{ I 997 \Iedicinal naturalproducts.a biosl'nthcticiipproach.John canilselfbe ofthe absuactsto covera broacllielclof intcrests searching W i l e y .C h i c h e s t e r lrtles and publicatictns as and such ClrcntittLl rnost tinre-consunrin-9. 6 t l r i n e g g e l E 1 9 9 9 P h a r m a k o g n o s i c P h y t o p h a r m a z i e . H i i n s eR l . S t i c h c rO . S t e CurrentCottentscan be usedto give a rrore rapidindicationof recent edn. Springer.Berlin (|ir C)t'ntrcnt1 bibRobbersJ E. SpeedicM K. Tl ler V E 1996 Pharmacognosyand pharmacoregularlyincludesa selected publications. Phltothenq1'Re.search b i o t e c h n o l o g lW ' . i l l i a m s& W i l k i n s .B a l t i m o r e lioglaphy relating to plant dlugs. Inlbrntatioti stot'ageanclretrieval is Tauchnitz.Leipz-iglttro editiort.s TschirchA Handbuchder Pl.tilrnako-unosic. occupiedby sucnow itself a scicnce.anc'la glanceat the shelf:space t oltnttt'strltto l 9-l-i1 tutd nunterou.s is sutlicierrtto indicatethatbetbre ceedingyearsof CftcrnlL:trlAb.strtLcts long. if not already'.manual searchesof the litcrature u'ill become With the increase in interest in rnedicinal plants world-wide there are Inevitablyit will bc necessalyto rely on inrpossiblylon-eprocedures. n o \ \ ' n r a n y p u b l i c a t i o n s c o \ ' e f i n g r c g i o n a l a l e a so f t h e g l o b e . T r e a t m e n t databasesfbr litelature scanniug.PltunnucogttostTitlesis a cornputcr of the plants in thcse wolks rna)' be on an1, of the abovc lines. Some researchpublicationsup to 1974 of phytochenrical abstl'act co\rerage cxamples are given fbllowing the Introduction to Paft VII.

4. Phormqcologicol or Theropeutic

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T H ES C O P EA N D P R A C T I COEF P H A R M A C O G N O S Y tl0 vols) producedundel the directionof Prof-essol N. Farnsr','or.th.as anv book can). Symposiall,hich cor,ervaLiolrsaspectsof pharnraI i n i ' " ' e r s i t y o f I l l i n o i s . S u b s e q u c n t l y .F a r n s w o r t h i n t r . o d u c e c lcognosyarc tiequently held in variouspartsofthe world and scientists \APRALERT. a NaturalProcluctDarabasewhich is rrainly. br.rtnor can easilvbecomeacquninted u'ith othershar,inglike interests. Often cntirely.post-ltl75and is vieu.'ed bv rrany as a logicaland inclispens- the infbn-r-ral discussionswhich invariably ariseat sr.rch meetingscanbe able collectiono1'pharmacognostic information.The NAPRALERT an extremelyuselulnteansof disseminating infbrmation.ln addition, database is availableon a schedulcd-fee basisft) scientists.industrial the lecturesplesentedat such nteetingsare often sr.rbsequentlv pubfirns. -qovemment agenciesand acadenticinstitutions. Among othcr lished in book fbrm. Modern comntunicationsystemsmake u'orlduselirl databaseshaving a reler,'ance to pharntaco-tnosy and published '"videcontactbetweenresealchers much sintpler. on the Web arc MEDLINE. conrpiledby the US NarionalLibrarl,of Now al'ailableto Westernscientists interestcd in orientalrnedicineis Medicineand EMBASE. producedby ExccrptitMedica. the qualtelly joumal Abstnrc:t.s o.l'CltineseMeditirrc, publishedby the S o m e j o u l r r a l s f o r e r a r - n p l e .P l r t r t t u M e d i t ; u . . l o u r n o l o f ' ChineseUniversityol HorrgKong. This givesabstractsin Englishof Ltltrtophunrrut'ologv Plntocltetnisn'y nnd Jountttl of' NtttunLl significantChineseresearch papersfrorn morethanonehundredscienPt'o(luLt.\-periodicallycolttuin reviL-\\s on \oll(. i.rs|ectof medicinal titic journalsnot feadilyar,ailable outsideChina. plants.Otlrel pcliodical publicationsappearingin bor-rndfbr-m are Usefirl dictionaliesto be lbund in most Unir.ersitylibrtrriesinclude devoteclto reviewson certainaspectsof plar-rtconstituclttsand are use- DicticrttLryof Organic Contpountlsconsisting of 7 r'olurnesand 10 ful fbr updating;ofien the rcr,ielvscor,eronly the adrrncesin I parti- sLrpplements (to 1992).Dittiotmry ol Alkaloitl.s12 r,olunies)(1989). culal tlc-lclsincethe pler,iousr,olunte.Examplesare NtfturtLl Product Dictionar-t o.f Tbrpertritls( 19911and Dit:tionurt' of Natuml pnxlucts Reports(six issuespcl vear) .andAlkaloitl.y(AcadenricPrcss).Books (1994) all publisheclbv Chapmanand Hall and also phttot'hemictrl thatarenot partofa seliesbut. like the above,rrultiauthorand dealing Dictiornrt': A Hundbookol Bioactit'eCompountls.frcmplutfi.t ( 1993), \\'ithccrtainspeciaiized areas(c.g.alkaloids.flavonoids.isoprenoids). publishedby Taylol and Francis.Sorneof thesemore expensivevolcorrtinuallyappearand generallvgive up-to-dateinfolmation (in so flr Lrmesare availableon CD-ROM.

z

IE BOTANICAT NOMENCTATURE Beforethe time of Linnaeus( 1707 1778)many plantswere known by a double Latin title; however,it is to this great Swedishbiologist that we owe the generaladoptionof the presentbinon-rialsystem.in which the flrst narrc dcnotcs the genus, while the second(specific) name denotesthe species.All specificnamesmay be written with small initial letters although tirmerly capitals were used where specieswere named after persons. Thus the species of Cinchona named after CharlesLedger,who broughtits seedsliorn Brazil in 1865.is now writtcn Clrrry'rono Ietlgerionaratherthan CinchonuLedgerianu. The specificname is usually chosento indicatesome striking characteristicof the plant fbr example.the hemlock with the spottedstem is namedConiunrntaculuturtt(.mutulutus.-d. -1u11. spotted).Sometimes the reasonfbr the name is not as obvious as in the examplejust mentioned.but onceit is discoveredit will serveas a reminderofa characteristicof the plant-fbr example,Stl c/rnos potatorum (potator,-oris, a drinker) bearsa namewhich is only intelligiblewhen it is known that the seedsof this speciesareusedin India lbr clearingwater. The modernrules governingthe terrninologyof plant taxonomy are laid down in the Internroioncl Codeof BotanicalNomenclature. Unlike the names of chernical substances,which are subject to changeswhich confolm to evolving systemsof nomenclature. systematic plant namesare strictly controlledby ruleswhich give precedence to that name used by the botanist who first described the species. Nevertheless, this seeminglystraightfbrwardapproachcan give rise to variousquilks in spelling.The following are threeexamplesinvolving rnedicinal plants Rauvolfia vis ir vis RauwoLfia;the former name was given to this Apocynaceousgenusby Plumier in 1703,honouringthe botanistLeonard Rauwolf. This spelling ovelsight causednuch contentionover the yearscentringon whetherPlumier's obvious intention shouldbe adoptedin the nameRaLntollia.Both spellingsarecommonly fbund but the rules dictate that Rauvolfia has priority. In anotherexample the downy thornapplemay be encounteredas eilher Datura innoria or Datttra irnxia. The fbrmer. as Datura irutoxia Miller. was used in 1768(Gurd.Dlo.. edn.8, Dutttru no. 5) and this spellingwas invariably employedfor some200 years:howeverin Miller's original description. the plant was characterizedas: 'Datura (lnoxitt) pericarpiisspinosis inoxiis ovatis propendentibusfoliis cordatis pubescentibus'(W. E. Saflbrd,J. \Wrsh.Acud. Sci.. 1921,11,173) and taxonomistsnow considerD. irro-rlaMiller to havepriolity. Both versionsarestill commonly encountered. A third exarnpleconcernsthe genusofthe cocaplantwhich may appearas Er1,1fup.ry1u^, or in older literature as Erythrox:-lon.

Plont nomencloture ondtoxonomy

3. i

r

SUBDIVISIONS OF THEPHYTA The branchesofthe genealogicaltreediffer so much in sizethat it is not easyto decidewhich are of equalsystematicimportance,and what one biologist may consideras a lamily anothermay regardas a subfamily. Similarly. the speciesof one botanistmay be the subspeciesor variety of another.The main hierarchicalsubdivisionsof a division. aranged according to Engler's scheme.may be illustrated by the lollowing exampleshowingthe systematicpositionof peppermint.

h !: I

l

BOTANICAT NOMENCLATURE8 SUBDIVISIONSOF THE PHYLA

8

BOTANICAT SYSTEMS OF CTASSIFICATION9 TAXONOMICCHARACTERS9 PTANTTAXONOMY CHEMICAT

ro

Division Class Subclass Order Suborder Family Subfamily Tribe

Anglospermae Dicotyledoneae Sympetalae Tubiflorae Velbenineae Labiatae (Lamiaceae) Stachydoideae Satureieae

.q.#{

PLANTNOMENCLATURE AND TAXONOMY Genus Species Varieties

Mentha MenthapiperitaLinnaeus(Peppermint) Menthupiperita var.olrtcinalis Sole (White Peppermint) Menthupiperita var.vul,qari,s Sole(Black Peppermint)

It will be notedthat in pharn-racopoeias and in researchpublications botanicalnamesarefbllowed by the nar-nes of personsor their accepted (e.g.Linnaeusand Sole in the caseofpeppermintgiren abbreviations above).Theserefer to the botanistwho first describedthc speciesor variety.Studentsneednot attemptto memorizethesenames.and in the fbllowing pagesthey areusuallyomittedexceptin caseswheredif-fbrent botanicalnameshave at differenttimes beenappliedto the sameplant and thereis possibilityof confusion.The sourceof cloves,fbl example. is now usuallygiven asS,t';.r'glum aromaticltm(L.) Men. et Pen'y:prior to 1980 the B.P. used the name Eugetict -cooH

Hydroxyproline

Proline

COOH-CHOH-CH2OPO3Hz

.--------+COOH--CO-CH2OPO3H2

3-Phosphoglyceric acid

3-Phosphohydroxypyruvic acid

I COOH-CH.NH2-CH2OH +--+

coo H-c H.NH2*cH 2oPo3H2 3-Phosphoserine

Serine Serineand glycineare readilyinterconvertible: F i g .1 9 . 1 4 Formotion ondglycine of serine

-_

CH,OH-CH.NHr-COOH -r HCHO + CH2.NH2-COOH

rrr!-rls

"

PATHWAYS ANDTHEORIG|NOF SECONDARY METABOLTTESEg BASTC METABOLTC

fH'1oH

f"

cH2sH I +HCNHl

HCNH2

I cooH

+

i'-*f" HfNHr

ir'

COOH

HCNH2

cooH

cooH Homoscrinc Cystein€ (or relatcd 4-C compound)

Cystathioninc

n*,* It Plruvate

cHl

I

I

s I

9x, I 9Hr I

HCNH2

cHz-sH N5-methyl THFA

I

f"

HCNH2

cooH

I

cooH Methionine

Homocystcine

Fig. I 9.15 Originof methionine.

ical. chemical and pharmacologicalproperties.The lowest membersare derivedfrom only two moleculesof aminoacid.but highermembershave many amino-acidunits and lbnn eitherpeptides,simpleproteins(albumins, globulins,prolamines.glutalins,etc.) or more complex proteins. conjugatedproteins.in which other groupingsform parl of the molecule-fbr example,carbohydratein mucoproteins,the very cornplex phosphorus-containchlorophyllmoleculein the proteinof chloroplasts, ing proteinssuch as casein,nucleoploteins,in which proteinsarc combined with nucleic acid, and the lipoproteinsof the cytoplasm,in which protein is con'rbinedwith lipids.Among such substances with relatively 1owmolecularweight aresomeantibioticswhich havea cyclic polypep(e.g.gramicidin,bacitracinand polymyxin); peptidehortide str-ucture mones such as oxytocin and vasopressinfiom the posteriorpituitary gland;andglutathione,which is foundin nearlyall living cells. All thesemore or less complex compoundshave two or more mofrom leculesof amino acid united by a peptide linkage which resr"rlts the eliminationof water,an OH colning from one amino acid and an H fiom the other. Thus, a dipeptideis formed: R-CH(NH2)COOH+ R'-CH(NH2)COOH Amino acid

Amim acid

R-CH(NF|2)CO-NH-CH-R' + HzO Die€ptide

Alonine, voline ond leucine Studieswith microorganismsand yeastshave showntheseamino acids to be derived from pyruvate.There is evidencethat o-ketoisovaleric acid is aminatedto form valine and that it can also condensewith acetateto form an intermediatewhich on decarboxylationand amination affordsleucine(Fig. 19.16).

cooH

plant Blighictsupidu has hypoglyA dipeptideof the Sapindaceous caemic propertiesand although nore con-rplex.penicillin also has a dipeptidestructLlre. Tripeptideshavethreeamino-acidcomponentsand polypeptidesfrom ten upwards.Peptidesare usually defined as prohaving molecularweightsbelow I 0 000. In typical tein-like substances proteinsthe molecularweight is higher,ranging flom abor.rt30 000 to 50 000 in the relatively simple prolaminesand glutelins and reaching lsoleucine very high values,sometimesseveralmillion, in the complcx proteins This amino acid suchas thosein sheep'swool. Protein synthesistakes place in associationwith the ribosomes, cH^'cx-tx-coox T"t which are small bodiesfound in the cytoplasmand particularlyin the endoplasmic reticulum area (see Fig. 19.l). The amino acids are cHt-c+{ broughtto the ribosomesassociatedwith a transfer-RNAmoleculeand by the action of the ribosomes,using a sequencedictatedby a particular messenger-RNAmolecule,are linked to folm the peptidechainsof valine comtnencing series of reactions to but is formed by a similar the particularprotein.Although not directly relevantto most pharmaacid insteadof cx,-acetolactic acid. with o-aceto-cr-hydroxypropionic cognosticalstudies,the story ofthe nucleic acidsand their vital roie in the control ofcell metabolismis a fascinatingone which it is suggested Lysine studentsstudy liorn a standardwork on biochemistry. Lysine, H2N-(CH)4-CH(NH2)-COOH. is derived, in plants, from aspartateinvolving a pathway utilizing 2,3-dihydropicolinicacid and diaminopimelicacid.It is the precursorof somealkaloidsof Nicotiana, ISOPRENOID CON,IPOUNDS Lupinus andPunica. For a review of the biosynthesisand metabolism of aspartateStudieson the pyrogenicdecompositionof rubber led workers in the derived amino acids (lysine, threonine, methionine, S-adenosyl latter half of the nineteenthcentury to believe that isoprenecould be 1991,46,395. methionine)seeR. A. Azevedoet al., Phytochemistrl,-, regardedas a fundamentalbuilding block for this materiai.As a result of the extensivepioneeringinvestigationsinto plant terpenestructures. Aromqtic omino ocids 'biogeneticisoprenerule', which indiRuzickapublishedin 1953his Thesehave alreadybeenmentionedin the discussionof the biosynthecatedthat the appositionof isoprenoidunits could be usedto explain sisof aromaticcompounds. not only the formation of rubber and the monotelpenes.but also many other natulal products,including some,suchas sterolsand triterpenes, with complex constitutions.The value of the rule lay in its broad unilying concept,which allowed the postulationof a rationalsequence of events which might occur in the biogenesisof these otherwise 'peptide' includesa wide rangeof compoundsvarying from low unrelatedcompounds.Examplesof variousstructuresto which the rule The term to very high molecularweights and showing markeddifferencesin phys- can be appliedare indicatedin Fig. 19.17.

PHYTOCHEMISTRY

9Ht

cHr

6:O

c:o I

I

I cooH

cHr-c--oH I

c:o I cooH

cH3-c--oH I

cooH Pyruvicacid

cHr I cH3-c-oH I

9x, I

H-C-OH

I cooH apDihydroxyisovaleric acid

a.Keto-/-hydroxy isovaleric acid

cAcetolactic acid

II

J CHr

I

CHI

cH3-c-H

I

CH3-C-H

I C:O

+-

I

I cooH

H-C-NH2

I cooH

aKetoisovalericacid

Valinc

| "."."."

I condengation

+ \

cHj

/

i

cHr-cooH

,, ? n3L\

cH-cooH

6H3r

l

{_-

cH-c-cooH

/ Hlc'

I

cH_c_cooH l oH

p-Hydroxy-P-carboxYisocaProic acid

Dimethylcitraconic acid I

I * cH.oH-cooH I

cHr, \

cHrr

fo-cooH

- - - . } c H _ c\ H _ lc o o H / cHj

l

cH-cH-cooH

cHi

a-Hydroxy-pcarboxyisocaproic acid

cK eto-B-carboxyisocaproic acid

I

+ cHr\

a"r\

f*'

cH-cH2-cH-cooH Fig.I9.16 Formotion of volineond leucine

F-

cHt/ Leucine

The task set biochemistswas to investigatethe validity of the rule, and the work on this subjectconstitutesa brilliant exampleof modern biochemistrylhowever,as will be seenbelow, this chapterof research is still unfinished.By 195I it had beenestablishedthat aceticacid was intimately involved in the synthesisof cholesterol,squalene,yeast sterolsandlubber.The useof methyl- andcarboxyl-labelledaceticacid with animal tissuesindicated that the methyl and carboxyl carbons alternatedin the skeletonof choiesterolor squaleneand that the lateral carbon atoms all arosefrom the methyl group of aceticacid. The discovery,in 1950,of acetyl-coenzymeA, the so-called'active acetate', gavefurther suppoftto the role of acetatein biosyntheticprocesses.

*---ruD

/CH-CH2-CO-COOH CHz' acid oKetoisocaproic

The mevalonic acid pathway. The next major advancein the elucidation of the isoprenoidbiosyntheticroute was the discoveryin 1956 of mevalonicacid and the demonstrationof its incorporation,by living tissues,into those compounds to which the isoprene rule applied. Mevalonic acid (3,5-dihydroxy-3-methylvaleric acid) is a C6 acid and, as such,is not the 'active isoprene'unitwhich forms the basicbuilding block of the isoprenoidcompounds.During the next four years, by researchinvolving the use of tracertechniques,inhibitor studies,cellfree extracts,partition chromatographyand ionophoresisas well as syntheticorganic chemistry,it was establishedthat the C5 compound for which biochemists had been seeking so long was isopentenyl

d!-lr{Fr-"

1Is1Gll

BASICMETABOLIC PATHWAYS AND THEORIGINOF SECONDARYMETABOLITES

A ^n"' Vq;J

t:t:l'rr'i',, rlt. 'l::i":'l'' ..iiu,iall , )::a:1.:':'):

:.' :a:'

/\ Limoncnc Camphor --*-\rMonoterPenes

r-\

-,1[v

\

M L l l t' \

li]ltrt ":::,t ::,,1:l':'

fil:l l:11 lia:::i.....

T

,. L\,/-. 1

Rubber

I

x,c.

, ./ Tritcrpenes

T

.l J.

FCarotene

t"J'-E*' ,/

/IsoPrcne \

carotenoids

\

|

\.4.

Glycyrrhetinic acid Sesquiterpenes

Steroids

A't Fig.19.17 Applicotion of theisoprene rule illuslroting incorporotion of C5 uniis.

pyrophosphate; it is derived from mevalonic acid pyrophosphate by decarboxylation and dehydration. Isoprenoid synthesis then proceeds by the condensationof isopentenylpyrophosphatewith the isomeric dimethylallyl pyrophosphateto yield geranyl pyrophosphate.Further C5 units are addedby the addition of more isopentenyl pyrophosphate. Thesepreliminary stagesin the biosynthesisof isoprenoidcompounds areshownin Fig. 19.18. From geranyl and farnesyl pyrophosphatesvarious structurescan be built up (seeFig. 19.19). Studies, parlicularly by Cornforth and Popjdk, involving the use of stereospecifically3H- and laClabelled mevalonic acid, have demonsffated the stereochemicalmechanism of the initial stages of isoprenoid formation. Only the (R)-form of mevalonicacid gives rise to the terpenoids,the (S)-form appearingto be metabolically inactive. In the formation of isopentenyl pyrophosphate, the elimination is trans and the elimination of the proton in the isomerization to the dimethylallyl pyrophosphateis also stereospecific(Fig. 19.204').

E

) * Zngiberenc

In the subsequentadditions of the C5 isopentenylpyrophosphate units to form the terpenoids the elimination of hydrogen rs trans. Figure 19.208 shows the stereochemistryof the addition of one isopentenylpyrophosphateunit. In the biogenesisof rubber, however, the hydrogen elimination produces a cls double bond (Fig. 19.20C). It is consideredthat a simple changein orientation ofthe isopentenyl pyrophosphateon the enzyme surfacecould produce this changewithout altering the reaction mechanism. In neither rubber nor gutta are hybrid molecules containing both types of bond detectable.The first direct evidence for the presenceof isopentenyl diphosphateisomerase in rubber latex was reported in 1996 (T. Koyama et al., Phytochemistn, 1996, 43, 7 69). In recent years the enzymology of the isoprenoid pathway has been extensively studied and for details the reader is referred to a standard text on plant biochemistry.One key regulatory enzyme is hydroxymethylglutaryl-CoA reductase(EC 1.1.1.34,mevalonatekinase); it

:11:iilll:..ll

:::rlrt

PHYIOCHEMISTRY

OH ---)

CH3-COSCoA

2NADPH>

-ooc-cH+-cH2-coScoA

Acetyl-CoA

ix,

+

H ydroxymethylglutarate

CHTCOCH2COSCoA Acctoacetyl-CoA

oH I

HOCH2-CH2-C,-CH2_COOI cHr Mcvalonate

I ArP I

l OH

I - - -o5,P2ocHz-cHrt-cH2coo-

OH

I - -o3PocH2-cH2-c-cH2-coo-

ATP f--

I

I

cHr

CHr 5 Pyrophosphomevalonate

5-Phosphomevalonate

^rP - cor J - - -O6,P2OCH2-CH2-C:CH2 cHl Isopentenylpyrophosphatc

1l t l

--* a"t-i

t,

- cH3-c:cH-cH2oP2o6I cHr pyrophosphate Dimethylallyl

CH-CH2-CH2-C:CH-CH2OP2O6cHr

cHr Geranylpyrophosphatc

CH3-C:CH-CH2-CH2-C:CH-CH2-CHrC:CH-4 t t cHt CHI

| +l.op"nt"nyl lrroehosehate J

H2OP2O6,-- l CHI

Farnesylpyrophosphate Fig.I9.18 Preliminory stogesin the biosynthesis of isoprenoid compounds.

hasbeenextensivelystudiedin animalsand more recentlyin plants.As with many enzymesthe situation is complicatedby the existenceof more than one speciesof enzyme and a plant may possessmultiple lbrms each having a separatesubcellularlocation associatedwith the biosynthesisof different classesof terpenoids.For a review of the functions and propertiesof the important isomeraseenzyme isopentenyl diphosphateisomerasesee 'Further Reading'. It shouldbe notedthat somemetabolitesof mixed biogeneticorigin involve the mevalonicacid pathway;prenylationfor exampleis common, with Cs, Cro and C15 units associatedwith flavonoids, coumarins,benzoquinones, cannabinoids,alkaloids,etc. The validity of the mevalonatepathway in the formation of all the major groupsnotedin Fig. 19.I t hasbeenshown,and until recentlyno other biosyntheticroute to isoprenoidshad beendiscovered.

precursorfor all isoprenoidsyntheses.However, in 1993M. Rohmer et al., (.Biochem.J., 1993,295,517) showed that a non mevalonate pathway existed for the formation of hopane-typetriterpenoidsin bacteria. The novel putative precursor was identified as 1deoxy-o-xylulose-5-phosphate, formed from glucose via condensation of pyruvate and glyceraldehyde-3-phosphate. Subsequentsteps including a skeletal reaffangement afford isopentenyl pyrophosphate-the same methyl-branched isoprenoid building block as formed by the MVA route. It was soondemonstratedthat this novel route to IPP was also operative in the formation of monoterpenes(Mentha piperita, Thymus vulgcrls), diteryenes (Ginkgo biloba, Taxus chinensis) and carotenoids (Daucus carota). This raised the question of to what extent the two pathwaysco-existedin the plant and it was hypothesizedthat the classical acetate/mevalonatepathway was a feature of cytoplasmic reacThe 1-deoxy-o-xylulose(triose/pyruvate) pathway. Followingits tions whereas the triose/pyruvate sequencewas a characteristic of the discoveryin 1956mevalonicacid cameto be consideredthe essential plastids.This did not exclude either the movementof plastid-synthe-

h.

r;itc-.j!l.

4CJ'

"tI[

BASICMETABOLIC PATHWAYS AND THEORIGINOF SECONDARY METABOLITES A Me. -gH

c"""nyr!|fprrospr,"e -/ Monoterpenes, C16 (straightchain, cyclic and bicyclic)

|

Isopentenyl PYroPhosPhate

,--

TiXi'"" MVA-SPP

I Crspp Farnesyl pyrophoephatc

-/ / Sasquiterpenes,Cl5 / (openchain, / monocyclic / ,Z and bicyclic) / t caoPP

/

\ \

r \ Triterpencs Steroids

IPP

-\L*

Y" u"z\,cFLoen il.

Y \

DMAPP

\ C2oPP

/

|

"

t',,"*"*',

tim" sq,*J.", o,H,:"i", l,r

/ \

,df:{ftoPP H.' -F{o

,/

#a

H";\o;*'one

rf H".

i"

Ircpentenyr pyrophosphate

\

T

Me

Al

t""\

l t Carotenoids Gutta

,r,

FL. (.u. .)"Td.r."r{2oPP_

"' l,i. ^/r^'H"

x"^Tu cf .ue lc-cl^,cxropp

- "-fr'""ioi

--Ff,'

I

PP.J

x. $

Fig.19.19 Biosynthesis of isoprenoid compounds.

Me

Jk\.cHppp \H["

c sized IPP and DMAPP from the organelle to the cytoplasm or the translocationof a suitableCs-acceptorto the plastid. Evidenceaccumulating indicates a cooperative involvement of both pathways. Indeed recent work on the biosynthesisof the isoprene units of (K.-P.Adam and J. Zapp, Phttochemistry, chamomile sesquiterpenes 1998,48, 953) has shown that for the threeC5 units ofboth bisaboloxide A and chamazulene,two were mainly formed by the nonmevalonatepathwayand the third was of mixed origin. The deoxyxylulose(DOX) pathway has helped explain the previously reported rather poor incorporations of MVA into certain isoprenoids.Thus V. Stanjeket al. (Phytochemistry,l999, 50, 1l4l) have obtained a good incorporationof labelled deoxy-o-xyluloseinto the prenylated segment of furanocoumarins of Apium graveolens leaves, suggestingthis to be the preferred intermediate. Fig. 19.21illustrateshow [1-t:C]-*lucose, when fed to plants,can be used to differentiate IPP and subsequentmetabolites,formed either by the MVA pathway or the DOX route.

Hb.

/rx \.Me

"t"fc;d;,

e1/ ucH"oPe

@

x.jr cf..ue ;c-c.^.Hc

,

).1r"

Ft "e cl+oPP

I

t

PPOl"rHl

x".f ^..ue n-c"-\--s

['t'"

s;;t

Fig. 19.2O Stereospecific reoclions in lerpenoidbiogenesis. A, Formotion from mevolonicocid (MVA)of isopentenyl pyrophosphote {lPP)by trons eliminotion; isomerizotion to dimethylollyl (DMAPP). pyrophosphole B, Associolion of thetwo 5-C unitswilh ironseliminotion of hydrogen. C, As B but involvingformotion of cisdoublebondsos foundin rubber.

convertedto male pheromones.The literature concerning chemical ecology is regularly reviewed (J. B. Harborne.Nat. Prod. Rep., 1993, As indicatedearlier in Fig. 19.2,the basic metabolicpathwaysconsti- 10,327: 1997,14,83 1999,16, 509) and the volatile isoprenoidsthat tute the origins of secondaryplant metabolismand give rise to a vast control insectbehaviourand developmenthavebeenreportedon (J.A. array of compounds;someof theseare responsiblefor the characteris- Pickett, Nat. Prod. Rep., 1999, f6, 39). The enzymology associated tic odours,pungenciei and colours of plants, others give a particular with secondarymetabolism is now receiving considerableattention plant its culinary, medicinal or poisonousvirtues and by far the greatest and, with respectto alkaloid formation, a number of enzymesassocinumberare,on currentknowledge,of obscurevalue to the plant (andto ated with the biosynthesisof the tropane, isoquinoline and indole the human race). However, a number of modern authors suggestthat groupshave beenprepared.The biosyntheticorigins of thosemetabosecondary metabolites, rather than constituting waste products of lites of medicinalinterestareconsideredin more detail in Part 6. which metabolism,arebiosynthesizedto aid the producer'ssurvival.The pos- is arrangedprincipally accordingto biogeneticgroups. sible functions in the plant of one large group of secondary metaAlthough a number of the biogenetic groups are characterizedby bolites,alkaloids,are discussedin Chapter27. particularskeletalsffuctures,the actualchemicalpropertiesofparticuRecently, considerable attention has been directed to the possible lar compoundsare determinedby the acquisitionof functionalgroups. ecologicalimplicationsof secondarymetabolitesnot only in relationto Thus, terpenesmay occur as alcohols (menthol), ethers (cineole), plant-plant interaction but also concerning the inteffelationshipof ketones(carvone),etc.,and as suchhave similar chemicalpropefiiesto plants and animals.Various insects sequesterspecific alkaloids, irinonteryenoidcompoundspossessingthe samegroup; aldehydes,as an doids, lactonesand flavonoidswhich serveas defensiveagentsor are exampleof a functionalgroup, may be of aliphaticorigin (citronellal),

PHY1OCHTMISTRY

ro:

Ho-)!\-oH nv

oH

-Gtucose 11-13c1

\\ 'CHq l

^-n v-v

-

I SCoA Acetyl-CoA

II

t

CH3-CO-_CHz -CO-SCoA

cHo

i-

3oo-

Glyceraldehyde-3-P

\ \ \

Pyruvate

/ /

Thiaminediphosphateparticipation

\ ,\.// I Y -cH. t nn

Acetylacetyl-CoA

CHe l -CH2 HOOC C -.CH2- CH2OH

? *. CO

HO-CH I .cH2oP

I H-C-OH I HO_CH I -cH20P

1-Deoxyxylulose-5-P

I

OH Mevalonic acid

HaC ' \

//,c-cH2-cH2oPP

Fig. 19.21 Theincorporotion into of It-13C1-nlucose isopentenyl diphosphote: left,vio the mevolonic ocid pothwoy;right,vio the pothwoy. deoxyxyulose

HeC

HzC

.c-cH2-cH2oPP HzC

lsopentenyldiphosphate

lsopentenyldiphosphate

aromatic (cinnamic aldehyde), steroidal (some cardioactive glycosides);and resultingfrom the introductionof a heterocyclicsystemone biogenetic group may possess some of the chemical properties of another(e.g.steroidaialkaloids). A particular group of compounds may also involve different biogenetic entities; thus, the complex indole alkaloids contain moieties derived from both the shikimate and isoprenoid pathways. In contrast, the same structure,as it occurs in different compounds,may arise from different pathways, as has been previously indicated with the formation of aromaticsystems.

Stresscompounds These are compounds which accumulate in the plant to a higher than normal level as a result of some form of injury, or disturbance to the metabolism; they may be products of either primary or secondary metabolism. Common reactions involved in their formation are the polymerization, oxidation or hydrolysis of naturally occurring substances;many however, are entirely secondary in their formation. A

,ry

number of environmental and biological factors promote the synthesis of stresscompoundsand these include mechanicalwounding of the plant, exposure to frost, ultraviolet irradiation, dehydration, treatment with chemicals,and microbial infection (seephytoalexinsbelow). The productionof suchcompoundshas also beenobservedin cell cultures subjectedto antibiotic treatmentand in cells immobilized or brought into contact with calcium alginate. Examples of the latter include the formation of acridone alkaloid epoxides by Ruta graveolens, and the increasedproduction of echinatin and the novel formation of a prenylated compound by Glycyrrhiza echinata cultures. Stresscompoundsare of pharmaceuticalinterest in that they may be involved in various crude drugs formed pathologically (e.g. some gums and oleoresins)and potential drugs (gossypol);they are implicated in the toxicity of some diseasedfoodstuffs and they play a role in the defensive mechanismof the plant. In the latter area,the phytoalexins have received considerableattention in recent years and can be regarded as antifungal compounds synthesized by a plant in greatly increasedamountsafter infection. The antifunsal isoflavonoid otero-

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BASICMETABOLIC PATHWAYS AND THEORIGINOF SECONDARY METABOLITES carpansproducedby many speciesof the Leguminosaeare well known. Other phytoalexins produced in the same famity are hydroxyflavanones,stilbenoids,benzofurans,chromonesand furanoacetylenes. Sesquiterpenephytoalexins have been isolated from infected U/nus glabra and Gossypium.In the vine (Vitis vinfera) the fungus Botntis cinerea acts as an elicitor for the production ofthe stilbenesresveratrol (q.v.) and pterostilbene. Chemically, stresscompounds are, in general,of extreme variability and include phenols, resins, carbohydrates,hydroxycinnamic acid derivatives, coumarins, bicyclic sesquiterpenes,triterpenes and steroidalcompounds.For the promotion of stresscompoundsin cell culturesseeChapterI 1 and Table 11.1.

Furtherreoding Cordell G A 1995Changingstrategiesin naturalproductschemistry. Phytochemistry40: 1585-16 12 Dey P M, Harbome J B (eds) 1997Plant Biochemistry.AcademicPress, London

GraysonD H 2000 Monoterpenoids(a review coveringmid- 1997 to mid-1999).Natural ProductReporrs17(4):385 Ikan R (ed) 1999Naturally occurringglycosides.JohnWiley, Chichester,UK KnaggsA R I 999, 2000 The biosynthesisof shikimatemetabolites.Natural ProductReports 16(4):525-560; 11(3): 269-292 Kruger N T, Hill S A, Ratcliffe R G (eds) 1999 Regulation of primary metabolic pathways in plants. Kluwer, Dordrecht, Netherlands Ramos-Valdivia A C, Van der Heijden R, Verpoorte R 1997 Isopentenyl diphosphateisomerase:a core enzymein isoprenoidbiosynthesis.Natural ProductReports14(6):591-604 RawlingsB J 1998Biosynthesisof fatty acidsand reiatedmetabolites.Natural ProductReports15(3):275-308 Rohmer M 1999 The discovery of a mevalonate-independentpathway for isoprenoidbiosynthesisin bacteria,algaeand higher plants.Natural Producl Reports l6(5): 565-57,1 SeiglerD S 1998Plant secondarymetabolism.Kluwer, Dordrecht, Netherlands Singh B K 1999(ed) Plant amino acids-biochemistry and biotechnology. Marcel Dekker Inc., New York Wink M (ed) 1999Biochemistryof plant secondarymetabolism.Sheffield AcademicPress

E PART

6

Phqrmqcopoeiolq n d relqted drugs of biologicql orrgrn o

o

I !.

(

f ' i {,.

I

t

\

\ {

I

p structurallyand stereochernically spccific enzyr.nes has now received (stearo) I-S-ACP) experimental support.By this means(Fig.20..+) therangeof acetylenes CH3(CHr)7CH:CH(CH,)7-CO-S-ACP + HzO + NADP lbund in Basidiomycetesand in the Contpositae.Araliaceae and Urnbelliferaecan be derivedtiom linolcic acid via its acetylenic12,I 3loleoyl-S-ACP.1 dehydloderivative, crepenynicacid. an acid first isolatedfrom seeds The positionofthe introduceddoLrblebond in respectto thc carboxyl oils of CreTrrs spp. group is governedby the enzyme;hence.chain length ofthe substrate acid is most important.The hydrogeneliminationis specilicallycis but Aromotic ocids a ferv unusualfatty acids such as that in the seedoll of PLutir-tt gruno- Two commonaromaticacidsare benzoicacid and cinnamicacid tum with the structurel8:3 (9c.I lt.l3c) hayetrartsbonds.As illr.rstrat- (unsaturated side-chain), whicharcwiclclidistribLrted in natureand

Acetrte + malonate

I I

Y

CHI(CHilTTCOOH

Palmitic

II

+ CH3(CHilt6COOH

Stearic

I l-2H

Y

cH3(cHrTcHlcxlcxrlrcoox oleic l-2H CH3(CHjaCHacx-cxz-cHS Fig.20.l S e q u e n c eo f f o r m o t i o no f o l e f i n i c fottyocids in plonts.

6g16gt7cooH

Linoteic

I l-2H cH!-cH2-cHgcH-cH2-cHgcH-cH2-cHgcH(cHJTcooH

OH C H 3 ( C H 2h C H 2 - C H - C H 2 C O- S - C o A Intemediolep-hydrcry ocid of fotly ocid synthesis

/

./-,,o\ -

cH3(cHahCHzCH:CHCO-S-CoA

Fig.2O.2 Alternotive pothwoys for synthesis of unsoluroted fottyocids.

I n"ar'i- onc

lfurlherodditio.t of 5 r cr units { Sleoricocid

\ CH3(CH2l7Cx:CHCH2CO-S-CoA | *on,on o,

I3rczunirs Oleicocid

Linotenic

@

PHARMACOPOEIAL AND RELATED DRUGS OF BIOTOGICAT ORIGIN CHr(CH2}CH:CH(CHtTCOOH

Oleicacid

I I

Mcthionine

cH3(cHt5cH(oH)cHr-cH:cH(cHtTcooH Ricinoleic acid

, [H3C-S-CH2-CH2-CH(NHdFCOOH]

I

CH3(c Hj7-C\H -c H-( CH|TCOOH Dihydrosrerculic acid V cHz | -.*

c Hr(cHzh_\:t{cxrhcoox Fig.2O.3 Oleicocidostheprecursor of

Srcrculicacid

V

cHr

r i c i n o l e i co n d s t e r c u l i co c i d s .

CHr(CHJiCH:CH-CH2-CH:CH(CHjTCOOH

Linoleicacid

| _,* CH3(CH2)aC-C-CH2-CH:CH(CHTTCOOH

Crepenynicacid

l'" CH3-CH2-CH2-C

H:CH-C:C-C

Hz-CH:

C H(CHTTCOOH

I I

D e h y d r o c r e p e n y n iacc i d

Range of rcet)rlenet formcd by furthcr introduction of acetylenic bonds et the 'distal'

Fis.20.4

of morecules and bv chainshortenins in lr'l,fi:.l:Jl;1.,ti:Jr.crrboxvl sroup)

Formotion of ocetulenic fottuocids. oflen occur liee and combinedin considerableamountsin drugs such as balsams.Truxillic acid. a polymer of cinnamic acid. occursin coca leaves. Other related acids of fairly common occllrrenceare those having phenolic or other groupings in addition to a carboxyl group; suchare: salicyclic acid (o-hydroxybenzoicacid),protocatechuicacid (3,4-dihydroxybenzoic acid), veratric acid (3.,1-dimethoxybenzoic acid), gallic acid (3,4,5-trihydroxybenzoic acid) and 3,,1.5trimethoxybenzoicacid. Similarly. derived from cinnamic acid, one finds p-coumaric acid Q;-hydroxycinnamicacid), ferulic acid (hydroxymethoxycinnamic acid), catTeic acid (hydroxycinnamic acid) and 3,4,5-trimethoxycinnamicacid. Unbelliferone, which occurs in combination in asafbetida,is the lactone of dihydroxycinnamic acid. Acids having an alcoholgroup arequinic acid (tetrahydroxyhexahydrobenzoicacid), which occurs in cinchonabark and in some gymnosperms:shikimic acid. which is lound in Japanesestar-aniseand is an important intermediate metabolite; and mandelic acid, C6HsCHOHCOOH,which occursin combinationin cyanogeneticglycosidessnch as thoseof bitter almondsand other speciesof Prunus. Tropic acid and phenyllactic acid are two aromatic hydroxy acids which occur as estersin tropanealkaloids (q.v.).For examplesof the aboveseeFig. 20.5. Chlorogenicor cafleotannicacid is a condensationproductof caffeic acid and quinic acid. It occurs in matd, coffee, elder flowers, lime flowers. hops and nux vomica and is converted into a green compound, which serves for its detection, when an aqueousextract is treated with ammonia and exposedto air. See also 'Pseudotannins' (Chapter22). The biogenesis of the aromatic ring has been discussedin Chapter19.

DlBASlc AND rii,6As'ie'.l,Aci,ni.,'..'',.,,'..'.ll:'..,,..',l... Oxalic acid, (COOH)2,forms the first of a seriesof dicarboxylicacids which includes malonic acid, CH2(COOH)1,and sr.rccinicacid, (CH2)2(COOH)2.Closely related to malonic acid is the unsaturated acid fumaric acid. COOH-CH=CH-COOH. Malic acid contains an alcohol group and has the forrnula COOH CH2-CHOH-COOH. It is found in fruits suchas applesand tamarinds.A high percentageoitartaric acid, COOH-(CHOH)2-COOH. and its potassiumsalt occursin tamarindsand other fruits. The tribasic acids, citric, isocitric and aconitic are closely related to one another.The Krebs'citric acid cycle,which is discussedin Chapter 19,is very important.Citric acid is abundantin fruitjuices, and aconitic acid,which occursin Aconitumspp..is anhydrocitricacid.It forms part of the Krebs'cycle andthe glyoxalatecycle in microorganisms.

cH2.cooH I

I

HOC.COOH

I

cH2.cooH Gric acid

H.C.COOH -H,O

--€

tl il +H,O c'cooH -+ II cH2.cooH

cis -Aconitic acid

HO.C.COOH

I I cH2.cooH

H.C.COOH

lsocitric acid

Of recentinterestareopines.a group of substances formed by a host plant after infection with Agrobacterium spp.; a number of these compoundsaredi- and tri-carboxylicacids.For furlher detailsseeChapters 1 1a n d 1 2 .

HYDROCARBONS ANDDERIVATIVES @

cooH

I

I

I \

Z

t i l Y\ot"

Yot

I OMe

I OH

\-)

Veratric acid

Protocatechuic acrd

Benzoic acrd

Lower members of the series are found principally combined as esters e.g. methyl salicylate in oil of wintergreen and methyl and ethyl estersresponsiblefor some liuit aromas.Esterified long-chain alcoholsareconstituents of somepharmaceutically importantanimal waxes and include cetyl alcohol (Ct6Hi3OH), ceryl alcohol (C26H51OH)and myricyl alcohol (Cr0H61OH).Such alcoholsalso participate in the forn-rationof esterswhich are constituentsof leaf cuticular waxes: an example is CarnaubaWax BP which contains myricyl cerotate.

z\

t t l

cHz-o (B)

Fig.2O.7 Formotion of ocylglycerols; Rl, R2

R2cooK

+

I

lr,o.o*' cH2-oH _C_X XO

Rt cooK

cH2oH

1,2-Diocylglycerol

neutralizethe aceticacidfleedby the hr drolr rrr ol I g of the acetylated fat. The oil is tirst acetylatedwith acetic.rr)h\ilride. r.vhichcombines with any hydroxyl groupspresent.Becau:ethe:c iirr-absentlronr most fatty acids.the smallacetylvaluesLrsuall)ohlilinedlrc clueto relatively small amountsof sterols.In an oil suchas e.r\t()r()il. honcvcr.the acetyl value is high (146-150),ouing to thc lirfrc rinrountsof the hydroxy acid ricinoleic acid. Certainphysicalconstants of flxed oils and fut' urc'significant:specific gravity,melting point, refractiveinder and .onrctinre:optical rotation(e.g.castoroil). Table20.6 showshorr chcnricul.tilndlrrd\are relatedto chemicalcomposition.The gas chrunrat,rslilnirie.c'prlation and quantiticationof the acidsproducedby thc hrdlolr.i. ot :pc'cific fixed oils is an ollicial methodfor their identitlcationrindrlualitr control; type chromatogramsare included in the BP. Sonrc eranrplesof this applicationarementionedunderthe oils dcscribedbclou. Wqxes The term'wax', althoughsometimesapplicdto thc'hrclroearbon nrixturehardparaflin,is bestcontlnedto thosenaturalnrirturc'\e()ntuining appreciablequantitiesof estersderivedtiorn hichcr nronohrdlic alco-

Numericol prcperties of fixed oils. Approximotefo\ composition

Fotor oil

Meltingpoint, "C

Soponification volue

lodine value

Soturoted(%)

Almond Costor

-tB -tB

I 83-208 1Z 5 - t8 3

99-l 03 B4

0.3-2.s

t

I B s - t9 6 18 8 - r9 6 250-264 190-r 98 248 19 3 - t 9 5 192-198 I B0-190

79_BB 86-t 06 7-1 1 1 0 9 - tt 6 r3 . 5

^l \JIIVC

Arochis Coconut Coffonseed rolm

Theobromo Lord Cod liver

-5 to +3 23-26 0 (Before winterizing) 30 31-34 34-41 ^l

L l e o r O TU

*Ol. = oleic;Ln.= linoleic;tdepositspolmitinot 2'C.

aa

ta

s0-66 I 55-tB0

t l

7-20 IB 92 27 50 59 60 U n d elr5

(%) Unsoturoted B BO l . L n . 88-94 Ricinoleic; 5-,l5 Ol. Ln. 75-93 Ol. Ln. 82 Ol. Ln. B Ol. 2 3 L n .O l . 50 Ol. Ln. 4l Ol.Ln. 40 01. Over 85 with up to six unsoturoted bonds

LR I G I N P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO hols of the methyl alcohol seriescombined with fatty acids. In this seriesof alcoholsthe uembers chan-eefr"omliquids to solids.become less soluble in water and have highel ntelting points with increasein molecular wei-qht.The fi'st solid of the series is dodecyl alcohol, Cl2HrsOH. Waxes include vegetableproductssuch as carnaubawax 'wooland animalproductssuchas spermaceti.beeswaxand so-called fat'. Although waxesareabundantin nature(e.g.on epidermalsurfaces). a limited numberonly areof commercialimportance:someof the bestknown and theil chief alcoholsare given at the end of the chapter. An impoltant practicaldiff-erenccbetweenfats and waxesis that fats may be saponifiedby meansof either aqueousor alcoholic aikali but waxesare only saponifiedby alcoholic alkali. This fact is usedfor the detectionof fats when addedas adulterantsto waxes(e.g.fbr detecting 'Japanwax' as an adulterantin beeswax).Saponificationof the the fat wax estercetyl pahnitatemay be representedas: * alcoholicKOH --> Cl6HrsOH C15H.1.COOCrr,H3-l CetYlalcohol Cetyl palmitate + cl5Hl3.cooK Potassiumpalmitate While fats consist almost entirely of esters.waxes. in addition to estersof the cetyl palmitatetype. often contain appreciablequantities of fiee acids.hydrocarbons,fiee alcoholsand sterols.The hydrocarbons and sterolsare unsaponifiableand both spermacetiand rvool fat. of these,have high saponificawhich contain considerableqr.rantities tion values.If analyticaldata for fats and waxes are cornpared,it will of waxestend to be higher-for example. be notedthat the acid vah-res beeswaxcontainsabout l57r of fi"eecerotic acid. C26H5jCOOH.In most waxes,iodine valuesare relativelylorv and unsaponifiablematter is hish (Table20.7).

N IN G ACIDS, AtC O HO t5 P FU_G_S__C_O_NTAI AND ESTERS Tomorindpulp The drug consists of the fruit of the tree Tamarindus indica (Leguminosae)deprived of the blittle. outer part of the pericarp and preservedwith sugar'.The fiuits are about 5-15 cm long. They have a brittle ep:icarp.a pulpy mesocarp.through which run from the stalk aboutfive to nine blanchedfibres. and a leatheryendocarp.The latter forms from four to twelve chambers.in eachof which is a singleseed. ln the WestIndies the fiuits ripen in June,July and August.The epicarpsale removed,the fiuits arepackedin layersin barrels.andboiling syrup is poured over thern; alternatively,each layer of fiuits is sprinkled with powderedsugar.

Toble 2O.7

Tamarind pulp occurs as a reddish-brown.moist. sticky mass, in which the yellowish-brownfibres mentionedabove are readily seen. Odour'.pleasantand fmity; taste.sweetand acid. The seeds,eachenclosedin a leatheryendocarp,are obscurelyfbursided or ovate and abor-rt15 mm long. They have a rich brown testa marked with a large patch or oreole. Within the testa,which is very thick and hard. lies the embryo. The large cotyledonsare composed very largely of hemicellulosewhich stainsblue with iodine. The pulp containsfiee organic acids (about l}c/c of tartaric,citric and rnalic),their salts(about8% ofpotassiumhydrogentartrate).a litof invert sugar.It is reportedthat t1enicotinic acid and about 30--:l0clc the tartaric acid is synthesizedin the actively metabolizingleavesof the plant and then translocatedto the fruits as they develop.The addition of sugarto the manufacturedpulp, to act as a preservatlve,somewhat lowersthe naturalproportionof acids. Flavonoid C-glycosides (vitexin, isovitexin, orientin and isoorientin) occur in the leaves.The fixed oil ofthe seedscontainsa mixture of glvceridesol saturatedand unsaturated(oleic, linoleic) acids. Tamarind pulp is a mild laxative and was lormerly used in Conf'ectionof Senna:it has tladitional medicinalusesin the W Indies and in China and the leaves have been suggestedas a commercial sourceof tartaricacid. Mqnnq 'manna' is applied to a number of different plant products. The name The biblical mannawas probablythe lichen Lecarutraesculenta,which can be carriedlong distancesby wind. The only mannaof commercial importance is ash manna, derived frorn Fraxinus ornus (Oleaceae) The drug is collectedin Sicily. When the treesare about l0 yearsold. tlansversecuts are made in the trunk. A sugaryexudationtakesplace and when sufficiently dried is picked off (f1akemanna)or is collected on leavesor tiles. Manna occursin yellowish-whitepiecesup to 15 cm long and 2 cm wide or in agglutinatedmassesof brokenf'lakes,with a pleasantodour and sweettaste.It containsabout557cof the hexahydricalcohol mannitol, relatively small amountsof hexosesugarsbut larger amountsof the more complex sugarsmannotrioseand mannotetrose(stachyose). The tliose on hydrolysisyields glucose(1 mol) and galactose(2 mol). while the tetroseyields glucose( I mol), fructose( I mol) and galactose (2 mol). Manna has a mild laxativeaction.

BENZOIN Of the two commercial varieties of benzoir-r-Siam Benzoin and SumatraBenzoin-only the lattet is now includedin the BP. Sumatra Benzoin (Gum Benjamin)is a balsamicresin obtainedfrom the incised poralleloneurtrsPerkins stem of StyraxbenzoirtDryand, and Sry'ra-:r (Styracaceae). It is producedalmost exclusivelyfrom cultivatedtrees grown in Sumatra.althoughthe tree is also native to Javaand Borneo Siam benzoin.derived from Slr,rzr tonkinensis,is producedin a rela-

Chemicol ctandords of woxes.

Wox

Acid volue

Soponificotion volue

lodine value

Importontconstituents

Spermoceti Beeswox

Belowl t8-24

12 0 - l 3 6 volue) 70-80 (ester

below )

Cetylpolmitoteond cetylmyristote 72o/oesters,moinlymyricylpolmitote;free ceroficocid; sterylesfers

Cornoubo Wool fqt

4-7 Belowl

79-95 90-t 06

t0-14 r B-32

B-tI

Sterylesters,estersof otheroliphoticolcohols, fottyocidsond hydrocorbons

H Y D R O C A R B O NASN D D E R I V A T I V E S tively small areain the Thai provinceof Luang Probangand is mainly usedin perfumery. History. The drug was noted by Ibn BatLrta.who visited Sumatrain the fburteenthcentury,but was not regulally in-rported into Eulope until the sixteenthcentury. Collection and preparation. Sumatrabenzoinis a purely pathological product and there is sonte evidenceto show that its fbrmation is brought about not only b1' the incisions made. but also by lungi (see 'Stress Cornpounds'.Chapterl9). In Sumatrathe seedsare sou,nin rice fields,the rice shadingthe young treesduring theil first year.After the harvestingof the rice the treesare allowed to grow until they are about7 yearsold. Tapping, The rather complicatedprocessconsistsof making in eachtrunk threelines of incisionswhich aregradLralli'lengthened.The first triangular wounds are made in a vertical row about 40 cm apalt. the bark between the wounds being then sclaped smooth. The first secretionis verv sticky and is rejected.After rnakingfurther cuts.each about 4 cm above the precedingones,a hardel secretionis obtained. Further incisions are made at 3-rnonthly intervals and the secretion insteadof being amorphousbecontescrystalline.About 6 weeks after each fiesh tapping the product is scrapedofT, the outer layer (flnest quality) being kept separatefr"omthe next layer (intermediatequality). About 2 weeks later the strip is scrapedagain, giving a lower quality darker in color.rrand containingfragmentsof bark. Freshincisionsare then made and the above processis repeated.After a time the line of incisionsis continuedfurther up the tlunk. Grades. The above three qualities are not sold as such but ale blendedin Palembangto give the benzoin gradesof comr.nerce. The best grade containsthe most 'almonds' and the worst containsa few almondsbut abr.rndant resinousmatrix. The blendingis doneby breaking up the drug, mixing difl'erentproportionsof the threequalitiesand softeningin the sun. It was fbrn-rerlyerported aftel stampinginto tins but now the commelcial drug arrivesin plaited containerswith a plastic wrapping. Characters. Sumotrubenzoinoccursin brittle massesconsistingof opaque,whitish or reddish tearsembeddedin a tlanslucent.reddishbrown or greyish-brown,resinousmatrix. Odour. agreeableand balsamic but not very rnarked; taste, slightly acrid. Sianresebenz.oin occursin tearsor in blocks.The tearsare ofvariable sizeand flattened: they are yellowish-brown or reddish-brown externally, but milkywhite and opaque internally.The block folm consistsof snrall tears ernbeddedin a somewhatglassy,reddish-brown,resinousrnatrix.It has a vanilla-like odour and a balsamictaste. When graduallyheated,benzoinevolveswhite tumes of cinnamic and benzoic acidswhich readily condenseon a cool surfaceas a crystalline sublimate.On warming a little powderedbenzoinwith solr:tion of potassium permanganate,a faint odour of benzalclehycleis notedwith Sumatrabenzoinbut not with the Siamese.When an alcoholic solution of f-erricchloride is added to an alcoholic extract of Siamesebenzoin,a greencolour is produced.Sumatrabenzoindoes not give this test. The BP inclLrdesa TLC test tbl the absenceof Dammar gum.

Up to about 20c/rof fiee acids n-raybe plescnt. High-glrde nraterial Irom S. purullelorrcLtrwncontainsbenzoic acid3%, r.anillin 0.-5(Zancl cinnanricacict20-30%. The more expensiveSiamesebenzoindifl'ersfront the above irr that it containsinsufTicientcinnamicaciclto give an odour of benzaldehl,de rvhenwarmeclwith potassiurrlpermanganatesolution.The mnjor corrstitLrent(aboLrt7-5%) secms 1() be the ester coniferyl benzoate. Conif'erylalcohol.3-metl.roxy-4-hydroxycinnamyl alcohol.is fbund in the carnbial strp of both gvmnospermsand an-tiosperms.Other constituentsare fice benzoic acid. tritcrpenoid acids arrd vanillin. Sou're rccent (20001parcels of Siam benzoirremanatinglionr Hong Kong have been fbund to be heavily adrllteratedrvith Surnatlarnaterialand applicationof thepotassiumpermanganate test(seeabove)is essential. Alfied drug. Pulenthcutgben:.oitt.an infelior vadety ploduced in Sumatra.rnay be collectedfiom isolatecltreesfiom which the resinhas not beenstrippedfbr sometime. It is easiiydrstinguished, beingvery light in weight and breaking u,ith an irregulal porous fracture.It consistsalmostentirelyof reddish-broun re-sin.with only a f-ewvely small tearsenbeddcdin it. Palembang bcnzoinis r.rsed as a soufceof natural benzoicacid. Uses. Benzoin. r'n'hentaken intelnalll,. acts as an expectorantand antiseptic.It is mainly useclas an ingledient of friar's balsam.or as a cosmeticlotion preparedliom a simple tincture. It finds considerablc useworld-wiciein the fbod. drinks.perfiulelv rnd toiletrv industries:it is a componentof incense.

TOIU BAISAM Tolr.rBirlsamis obtainedby incision flom the trunk o1'Mlro,rtlon bulsomLrnt (L.) Hanr-rs. (a widely sprcacl polvurorphic species) (Lcguminosae),a large tree which cliltersbut little f}om that yielding balsamof Peru.Wild treesoccurin ColombiaandVenezuela irndin the former countly lalge quantitiesofbalsant lvereproducedin the neighbourhoodof the Magdalenaand Caucl rivers.The treesare cultivated in the West Indies.particularlyin CLrba. History. Balsamof Tolu i,vasdescribedbv Monardesin l-574and its collectionwasobserve clb-vWeir in 1863. Collection. The drug is collectedby making V-shapcdincisionsirr the bark. the secletionbeing reccived in a calabashplaced in the angleof the V. Many suchreceiversare tixed on eachtree.rhr')'ield per tree bcing B-10 k-q.Periodically.the balsarnis transf'erredto larger containers.It is exportedin tins fiont Cartagc.na. Sabanillaand Sta.Marta. Characters. When fieshly imported. tolu is a soti. yellow sernisolid. On keepingit trults to a bro$'lt. brittle solid. Jt sottenson warming. and if a little is then plessed betr.r'eentwo glass slides, microscopicalexaminationshou'scr'1-stals ol cinnamic acid. arnorphous resin and vegetabledebris.Oclouris arorratic and fra-erant:taste. aromaticlthe drug forms a plasticmasswhen chewecl. It is almostentirely solublein alu^olrol. the solutionbeing acid to litmus. and giving a greencolour with lerric chloride (the latter possibly owing to the presenceof resinotannol). Like other drugs containing cinnamic acid, it yields an odour of benzaldehydewhen a filtered decoctionis oxidizedwith potnrsiurnpennanganrtL' solution.

Constituents. Sumatra benzoin contains fiee balsamic acids (cinnamic and benzoic) and estersderir,'edfiom them. Also presentare triterpenoidacidssuch as siaresinolicacid (19-hydroxyoleanolicacid.) Constituents. Tolu containsabor-rt80% of resin derived from resin and sumaresinolicacid (6-hydroxyoleanolicacid). For the formula of alcoholscombinedwith cinnamicand benzoicacids.The drug is rich oleanolicacid seeunder 'TriterpenoidSaponins'.The contentof total in free aromaticacidsand containsabout l2-157c of fi"eecinnamicand balsamicacids (calculatedas cinnamic acid) is at least 20%. and the about 8clcof free benzoic acid (acid value fiom l 00- I 60). Other conarnountof cinnamic acid is usuallv about double that of benzoicacid. stituentsareesterssuchasbenzylbenzoateand benzylcinnamateand a

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LR I G I N P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO little vanillin. Recentinvestigationshavc shown the presenceof other cally. The chief balsamic estcrs present are benzyl cinnamate(cinesters.styrene,eugenol.vanillin. l'erulic acid. 1,2-diphenylethane.namein) C6H5CH=CHCOOCH2C6H5(sap. value 23zl). benzyl benhydrocarbonsand alcohols.The balsamalso zoate(sap.value 264.3)and cinamyl cinnamate(styracin).The drug mono- and sesquiterpene Tolu containsfi'om 3-5to 50% of total alsocontainsabout287cof resin,which is saidto consistof perulesinotritcrpenoids. containsnllmerous tannolcombinedwith cinnamicandbenzoicacids.alcohois(nelolidol. balsamicacidscalculatedon the dry alcohol-solublematter. thrnesoland benzyl alcohol) and small quantitiesof vanillin and frcc Uses. GenuineTolu balsarnis difTicultto obtain and the BP now uses cinnarnicacid. Tolu-flavourSolution.containingfive aromatics,fbr the preparationof Work on the isoflavonoidscontainedin the trunk-wood has indiTolu Syrup.Balsarnof Tolu has antisepticproperties.It was a common cated that considerablechemical diff'erencescharacterizethe various ingr"edientof cou-ehmixtures, to which it was added in the fbrrn of gtt:tup. fbrms or speciesof the M. bcLlsantLun syftlpor tlncture. Uses. Balsam of Peru is used as an antisepticdressingfbr"wounds and as a parasiticide.Now that it is no longer usedin Tr-rllegras dressPERUBAIsAM ings, it is of less currentinterestin Westerrrmedicine.Taken internally it is used to treat catarrh and diarrhoea.Allelgic responsesrre balsantumvar. of M.r'rc-n'lon frorn the trunk is obtained of Peru Balsarn pereirae (Leguminosae),after it has been beatenand scorched.The drug is ploduced in Central Arnerica (San Salvador,Honduras and Guaterrala)and is now includedin the EtrropettnPharnurct4toeiaand the BP (2000). History. The drug clerivesits name fiom the tact that when first imported into Spain it came via Callao in Peru. It was known to Monardes and the nethod of preparationwas describedas early as 1576. although aftelwards fbrgotten. In 1860 the coilection was describedand illustratedby Dorat.

possible. Prepored sforox PreparedStorax is a balsam obtained from the wor-rndedtrunk of purified. and sr.rbsequently Licluidamburorientalis (Hamamelidaceae) fbund srnall tlee fi'om a and is obtained Levant storax This is known as in the south-westof Turkey.

Collection and preparation, In the early summerthe bark is injured by bruising or by making incisions.After a time the outerbark may be pared olT, or the whole bark may be lefi until the autumn.when it is Collection and preparation. ln Novernber ol December strips of removed.The piecesof bark are pressedin horse-hairbags.lirst in the bark, nreasuringabout 30 x l5 cm. are beatenwith the back of an axe cold and againafter steepingin hot water.Sometimesthe bark is boiled or other blunt instrument.The bark soon cracksand may be pulled off in the Eastfor with water and againpressed.The exhaustedbark is r-rsed aiter 2 weeks.As in the caseof Tolu balsam.the secretionis purely fumigation.The crudeor liquid storaxis exportedin casksfiom Izmir. pathologicalin origin and r,ery little balsan can be obtainedfrom the Storaxis obtainedby dissolvingthe crudebalsarnin alcohol,filterbark unlessit is chan'edu'ith a torch about 1 week after the beating. ing and recoveringthe solventat as low a temperatureas possibleso as The balsarnproducedin the bark is obtainedby boiling the bark in not to lose any of the volatile constituents.The alcohol-insolublemat(preparedwithout fire) ot halstuttct water and is known as t(lcLtusottte ter consistsof vegetabledebrisand a resin. (balsamof the bark). de cctst:ard The greater part of the balsam. ho*ever. is prepared, after the Characters. Crtrdestorttr ts a gt'eyish,viscousliquid with a pleasant removal ofthe bark, by the secondmethod.The balsamwhich exudes odour and bitter taste. It usually contains about 20-30% of water. is soakedup with rags.which. aftel somedays. are cleanedby gently About 82 879t is alcohol soluble. Purified.s/orz,rfbrms a brown. viscous.semisolidmasswhich loses boiling u'ith water and squeezingin a rope press.The balsarnsinks to (.balsamo not more than5c/aof its weight when dried on a water-bathfor t h. It is the balsam decanled. been watel having and, the the bottom completelysolublein alcohol and partially in either.It has a characterde trapo) is pouredoffand strained. and istic balsamicodour and taste. Less destructivemethodsof preparationhave beeninvesti-qated replacement of include the removal of narrow strips of bark and the Constituents. Storax is very rich in free and combined cinnamic recovthe tree With treatment this of a hot iron. with the use scorching acid.After purilicationit yields 30-,47Vcof total balsamicacids. els in 6 months, comparedwith 8 years aller the drastic traditional By steam distiltation storax yields an oily liquid containing method.The drug is chielly exportedfrornAcajutla (SanSalvador)and pbenylethylene(styrene),C6-H5CH=CHr.cinnamicestels,vanillin and Belize (British Honduras)in tin canistersholding about27 kg. portion of the drug consistsof resin fiee cinnamic acid. The resit.tot-ts with cinnamicacid.The presand combined present both fiee alcohols Characters. Balsam of Peru is a viscid liquid of a somewhatoily is shown by the odour of benzaldeir-r thc drug acid of cinnamic it is ence seen in bulk. When stringiness. nature,but fiee fi'om stickinessand when the drug is mixed with sandand warmed dark blown or nearly black in colour. but in thin layers it is reddish- hyde which is prodr.rced The original containershave a u'hitish scum on with a solutionof potassiumpermanganate. blown and transparent. Recent researchcarried out in Turkey has shown the presenceof the surface.The balsam has a pleasant,somewhatvanilla-like odour compounds not previously reported; these include monotermany taste. and an acrid, slightly bitter penes.phenylpropanesand aliphaticacids. The drug is almostinsolublein water.It is solublein one I'olume of alcohol (90%), but the solutionbecomesturbid on the addition of furAlfied drug. American storax obtainedfrom L. s1'rociJlua,alarge ther solvent.The relativedensity,l.14-l.l'7, is a good indicationof tree found near the Atlantic coast from Centlal America to purity, and if abnorrnalindicatesadulterationwith fixed oils, alcohol, Connecticut.is also used in the USA. This balsarn resemblesthe kerosene.etc. The BP includestestsfor the absenceof artificial bal- Levant storaxin constituents.Thirty-six comporLnds havebeenidentiin petroleumspirit). fixed oils (solubilsams(solubility characteristics fied in the leaf'-oil of the plant and tannins and related phenolics ity in chloral hydratesolution)and turpentine(odourtest). obtainedfiorn cell cultures. Constituents. The ofllcial drug is requiredto contain not less than Uses. Storax is chiefly used in the preparationof friars' balsamand '70Vc wlw of esters,assayedgravimetri- benzoininhalation. 45.jVawlw and not more than

H Y D R O C A R B O NASN D D E R I V A T I V E S

PHARMACEUTICATFIXEDOILS AND FATS ATMONDOIt Alrnond oil is a llxed oil obtained by expressionfiom the seedsof (Rosaceae)yar.tlulcis (sweetalmonds),or P all.1gPnuuts turtygdalrr^s drtlus var. unnru (.biIteralmonds).The oil is mainly ploduced liom almonds grown in the cor.rntriesbordering the Mediterranean(ltaly, France,Spainand North Africa). Characters of plants and seeds. Al-r-rondtrees are about 5 m in height and the varieties,exceptlbr difI'erencesin the seeds,are ahrost indistinguishable.The young fiuits have a soft, t-elrlike pelicarp, the inner part of which gradually becomessclerenchymatous as the tiuit ripensto forn'ra pitted endocarpor"shell.The shells,consistin,emainlv of sclerenchymatous cells. are sometimesground and usedtt'radulteratepowdereddr-r,rgs. The sweetalmondis 2-3 cnr in len-qth.roundedat one end and pointed at the ofher.The bitter almonclis 1.5-2 cm in length but of similar breadthto the sweet almond. Both varietieshave a tl-rin.cinnamonbrown testa which is easily removed after soaking in warm water. a processwhich is known as blanching.The oily kernelconsistsof two large. oily planoconvexcotyledons.and a small plumule and radicle, the latter lying at the pointed end of the seed.Sorre almonds have cotyledonsof unequalsizesand are iffegularly tblded. Bitter almonds al'e sometimesfbund in samplesof su'eetalmonds.particularlythose ofAfrican origin: their plesencemay be detectedby the sodiumpicrate test fbr cyanogeneticglycosides. Constituents. Both varietiesof almondcontain40 55c/cof fixed oil. about207cof proteins,mucilageand emulsin.The bitter almondscontain in addition2.5-1.}c/cof the colourless.crystalline.cyrnocenetic -qlycosideamygdalin(seeChapter'26). Alnrond oil is obtainedby grinding the seedsand expressingthernin canvasbags betweensli-ehtlyheatediron plates.They are bometilnes blanchedbefore-erindir-rg, but this doesnot appearto be of any particlllar advantage.The oil is clarified by subsidenceand filtration. It is a pale yellow liquid with a slight odoLu'andbland,nutty taste.It contains a considerableamount of olein. with smaller quantitiesof the glycosidesof linoleic and other acids.The usualstandardsfbr fixed oils (glc of fatty acids)are includedin the -BPto-qether u'ith testsfbr absenceof variousother oils and sterols. EssentiaLor yolatile oil o.falmotds is obtainedfron'rthe cake left afier expressingbitter ahnonds.This is maceratedwith water for some hor.rrsto allow hydrolysis of the amygdalin to take place. The benzaldehydeand hydrocyanicacid are then separatedby steamdistillatlon. Bitter ahnond oil containsbenzaldehydeand 21% of hydrocyanic acid. Purified volatile oil ofbitter almondshas had all its hydrocyanic acid removedand thereforeconsistsmainly of benzaldehyde. Ht'drogenatedAlmond Ol1is alsoincludedin the ,BP Uses. Almond oil is used in the preparationof rnany toilet articles and as a vehicle fbr oily injections. When taken internally. it has a mild, laxativeaction.The volatilealmondoils are usedas flavouring agents.

ARACHISOIL Arachis oil is obtained by expressionfiom the seeds of Arachi.s Itt'pctguea(Legun-rinosae)(earth-nut, g,rrnnd-nut.peanut) a small annualplant cultivatedthroughouttropicalAfrica and in India, Brazil, southernUSA and Australia.Various senotvDesexist which show dif-

f-erenccsin the relative amounts of fatty acids contained in the oil. Enormousqr.rantities of the fiuits and seedsare shippedto Marseilles and other Er.rropean ports lbr expression.Ground-nutsare the w'orlcl's fourth iargestsor.rrce of fixed oi1. Preparation, During ripening the fruits buly themselves in thc sandy soil in which the plants grow. Each fruit containsflom one to three reddish-brownseeds.The fruits are shelledby a machine.The kernelscontain-10-.50%of oil. Owing to the high oil contenrthe seeds. when clushed. are somcwhat difllcult to express.Atter the initial 'cooking'.part ofthe oil is lcmovedin a low-pressure expellerandthe cake is solvcnt extncted. The two oil fiactions are then rnixed before purification.The presscake firrrnsan excellentcattlefbod. The ground per"icarps havebeenuscclrs ur.tadr-rlterant of powdeleddru-us. Constituents. Arachisoil consistsofthe glycelidesofoleic. linoleic, palmitic,arachidic,steanc.lignocerrcanclothel acids.When saponified with alcoholicpotassiunr hr droricle.crt'stalsof impurepotassitur arachidateseparateon standing.-\rachis oil is one of the most likely adulterants of otherfixed oils (e.g.olivc oil). The BP examinationof the oil is similarto that mentione(lunclcr'C)livcOil' below: the temperatureat which the cooling.h1'dlolrsecl oil be-contes cloLrdyshould not be below 36"C. As with olive oil nrore strinsentstandardsare requiredfor oil to be usedparenterally. The hydrogenatedoi1is alsoofTicial. Uses. Arachisoil hassimilarpropertiesto olir e oil. It is rn insredient of camphoratedoil but is usedmairrlf in the-produetion of ntargarine. cookingfats,etc.

CASTOROtt Castoroil (c'old-drawncastoroil) is a fixed oil obtainetltronr 1l.rc sceds of RicinLtsconununis (Euphorbiaceae).Thc ll'r-ritir r rhrcc ccllecl thornycapsule.The castoris a nativeof India:thc prineipalpnrducing countries are Brazil. India. China. the fbrnrcr Sor iet L'niorr and Thailand.There ale about l 7 varieties.which nrar be rouqhlr _llouped into shrubsand treesproducinglargeseeds.and annuulhcrbsproducing smallerseeds.It is mainlv the smallervarietie:thul .rrc.nou cultivated and these have been developed. br br-ecdtng.to give high-yieldingseed plants.Mechanicalharrestingrs norr replacing hand-picking. Characters of seeds. The seedsshou consiclcrable clifflrencesin sizeand colour.They areova1.somewhatconrprL-\\cd. 8 l8 mm long and4 12 mm broad.The testais vcrl'sntooth. thin and brittle.The colourmay be a more or lessunifbrm grL-\.[]r'o\\n ol black.or may be variously mottled with brown or black. .\ small. ofien yellowish. caruncleis usuallypresentat one cnd. lronr nlrich luns the rapheto terminatein a slightly raisedchalazaat thL-oppositeend of the seed. The testa is easily remor,edto disclosethe papery remainsof the nucellussurroundinga largeoill'cndosperm.Within the latterlies the embryo,with two thin. flat cotl'leclons and a radicledirectedtowards the caruncle.Castor seeds,if in sood condition, have ver:ylittle odour: taste,somewhatacrid. ll'the testasare broken.ranciditvwill develop. Preparation and characters of oil. Ninety per cent of the wolld's castoroil is extractedin Blazil nnd India. Relativelysmall amountsof the whole seedsale now exported.The various pl'ocesses involved in the preparationof castor oil are describedin the 8th edltion of this book. Briefly, the seedsare deprived of their testasand the kernels cold-expressedin suitable hydraulic presses.The oil is refined by stearning,filtration and bleaching.Cold expressionyields about 337c

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P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO LR I G I N of r-r-redicinal oil and t'urthcrquantiiiesof oil of lorver quality may be obtainedby other methods Medicinal castoroil is a colourlessor pale yellow liquid. with a slightodourandtaintll,acridtaste.For its chenricalandphysrcalconstants.see the phalrnacopoeias. The acid value increasessomewhat with age and an initiall,v high r,alue indicates the use of darr.raged seedsor carelessextractionor storage.Castoroil has an extremely high viscosity. Constituents. Castorseedscontain46-53c/cof lixed oil. which consists of thc glycosides of ricinoleic, isoticinoleic. stearic and dihydroxystearic acids.Thc purgativeactionofthe oil is saidto be due lo free ricinoleic acid and its stereoisor-ner, which are produced by h1'drolysis in the duodenum.Theseacidshavethe formula.

cHrlcH,lscH(oH)cH.cH:cH IcH l,lTcooH For thebiogenesis ofricinoleicacid.seeFig. 20.3.Castoroil andthe oil from Ricinu,s:.cutT.ibariuus are remarkablelbr their hi-ghricinoleic acid content,which is about887cand92'/c,respectively. The cake lelt afier expressioncontainsextremelypoisonoustoxins knou'n asricins,which rnakeit unfit fbl useasa cattlefood. ln the body they prodrlcean antitoxin (antiricin).Ricin D is a sugarprotein wtth a stronglethal toxicity; it contains.193arnino acids and 23 sr.rgars. Two otherricins.acidicricin and basicricin, havesimilarproperties. Ricin 'Abrr-rs and abrin (see Seeds'below)exhibit antitumou properties.The seedsalso contain lipasesand a crystallinealkaloid.r'icinine,which is not rnarkedlytoxic and is stluctr.rallyrelatedto nicotinamide. Uses. Castoroil. oncervidell'usedasa domesticpurgatire. is noir more restrictedto hospital use lbr adninistration after fbod poisoning and as a prelirninary to intestinalexamination.Owing to the presenceof ricin, the seedshiive a nruch more violent action than the oil and ale not usedas a purgativein the West. The oil is a constituentof llexible collodion. HydlogenatedCastorOil USP/NF (19951is usedas a stifl'eningagent. Undecylenicacid.which is prepaledlrom castoroil, is usedin lungistatic preparations. (polyethoxylated asis alsoits zinc salt.Nonionicsurfactants castoroils) of variablecompositionareprodr.rced by thereactionof castor oil with etl-rylene oxide and are useclin certainintravenouspreparations whicl-rcontaindrugswith low aqr.reous solubility.The oil and its derivatives flnd many nonpharnraceutical usesinchrdingthe nanufactureof plasticizers TurkeyRed O11.soaps,paints.r,'iunishes. and lubricants. Allied drugs. Crctut .seetlsare obtained fron Croton tiglitun (ELrphorbiaceae), a small trce producing similar capsulesto those of castorbu1devoid of spines.The seedsresemblecastorsecdsin sizeand shapebut have a dull. cinnarron-browncolour and readily lose their carunclcs.They contain about 50% of fixed oil which uontainscloton resin;also 'crotin', ii mixtureof croton-globulinand croton-albumin compalablewith ricin. The oil also containsdiestersof the tetracyclic diterpenephorbol (esterifyingacid at Rl and Rl. Rl = H in the fbrmula below):acidsinvolvedareaceticas a short-chain acid.andcapric,lauric and palmiticas long-chainacids.Thesecompoundsarecocarcinogens and :rlso possessinflammatory ancl vesicant properties (see 'Ditelpenes'). Also presentare phorbol-12.13,20-triesters 1Rl. Rr and R3 are all acyl groups in the fbrmula shown).These are 'cryptic irritants', so callcd becausethey are not biologicallyactiveas suchbut becomeso by removal of the C-20 acyl group by hydrolysis.Rotation locular counter-cuffentchromatography(q.v.) has been used to separate thesetwo groLlpsof esters.A number of the phorbol estershave been tested for anti-HIV-I activity (S. El-Mekkawy et al., Phytochemistry'.2000. 53. .157).The plant also contains alkaloids. Croton oil shor-rlcl be handlcd with extremecaution: it is not used in Westernmeclicine.but if takeninten-rally,it actsas a violent cathartic.

Phorbolestersof croton oil Plttsic nttts or Purging nuts Llrethe seedsof Jatropha cLtrcos,another menrberof the Eupholbiaceere. The seedsare black, oval and 15-20 mm in length.They contain about 40% offixed oil and a substancecompalable with ricin, called culcin. Both seedsand oil ale powerful purgatives. (prayerbeads)are the attractivered and black. but poiAhrus .seed.s sonous,seedsof Abrus precaktrils (Leguminosae).They contain a toxic glycoprotein(abrin) resemblingricin togetherwith anothernontoxic peptidehaving haemagglutinatingproperties.Various alkaloids (abrine.hyaphorine.precatorine)of the indole type havebeenreported. also various sterolsand lectins.The seedshave been r.rsedin folklore medicinein Asia.Africa and S. America to treatmany ailments,alsoto procureabortionand to hastenlabour.In lndia they areemployedas an oral contraceptiveand asthey areremarkablyuniform. and eachweighs about I carat(c. 200 rrg), havebeenusedtraditionallyas weights.

ouvEorr Olive oil (sulad oil, n'eet oil) is a fixed oil which is expressedfrom the ripe lruits oI OIea eurq)oeo (Oleaceae).The olive is an evergreentree, which lives to a greatagebut seldomexceeds12 m in height.It produces drupaceousfruits about 2-3 crn in length. The var. ltttifolitt bearsIarger f'ruitsthan the var.ktngifolln, but the latteris saidto yield the bestoi1.The oil is expressedin all the Mediten'aneancountriesand in Califbrnia. haly. Spain,France,GreeceandTunisiaproduce90clcofthe world's production. Olive oil has been ranked sixth in the world's production of vegetable oils (F. D. Gr.rnstone et ul.. 1994,The Lipid Handbooft,Chapman andHall). History. The olive appearsto be a native of Palestine.It was known in Egypt in the seventeenthcenturyBC, and was introducedinto Spain at an early period. Collection and preparation. The methodsusedforthe preparationof the oil naturally vary somewhataccordingto local conditions.In the modern factorieshydraulic pressesare widely used but in the more remotedistrictstheprocedureis cssentiallythat which hasbeenfollowcd for hundredsof yealsandis describedin earliereditionsof this book.The first oil to be expressed from thegror.rnd fruitsis known asvirgin oil; subsequentlythe marc may be solvent extractedto obtain the lower quality oil. The superiorgradesof oil areextravirgin. virgin andpure or reflned. Characters. Olive oil is a pale yellow liquid, which sometimeshasa greenishtint. The amountof color-rring matterpresent,whetherchlorophyll or carotene,appearsto detenninethe naturalfluorescenceof the oil in ultravioletlight. The oil has a slight odour and a bland taste.If the fruits used have beenallowed to ferment.the acid value of the oil will be higher than is officially permitted. It should comply with the tests for absenceof arachisoil, cotton-seedoil. sesameoil and tea-seedoil. The latter oil, which is obtainedfrom China. is not from the ordinarv tea plant but liom a tree, Cantelliuso.t(tnqua.

HYDROCARBONS AND DERIVATIVES Constituents. Olive oils fiom different sourcesdiffer somewhatin composition.This may be due eitherto the useof the dilferent varieties of olive or to climatic differences.Two types of oil may be distinguished:(a) that producedin Italy, Spain,Asia Minor and California. which containsmore olein and lesslinolein than type (b), producedin the Dodecaneseand Tunisia.Typical analysesofthese typesare:

Oleic acid Linoleic acid Palmitic acid'l Stearicacid J

Tj'pe(a)

T'pe (b)

BP limits

Vc

Vc

ch

78-86 o-1

65-'70 10-15

9-12

1)

56-85 3.520.0 [7.s-20.0

io.s-s.o

triglyceridescontainingonly the shortand mediumchain-lengthfatty acids(e.9.octanoic,decanoic;seeTable20.2).It maintainsits lor.',, r'iscosity until near the solidillcation point (about 0'C) and is a useful nonaqucousmedium fol the oral adrninistrationof somemedicaments. Metliurtt-chairtTrigbceritles BP, EP, svnonymouswith the abovc, may also be obtainedflorn the dried endospermof Elaeis guineen.si.s (Palmae).The fatt1'acidcornpositionof the hydrolysedoil, determined by GC, has the fbllou'ing specifications:caproic acid ), 2c/c,caprylic acid 50-80%, caplic acid 20-5OC/o,lauric acid > 3.\ch, n.ryristic a c i d) 1 . 0 % .

COD.LIVER OIt AND HAIIBUT.IIVER OIt SeeChapter3 I

COTTONSEED OIt

The characteristicodour of olive oil, particularlythe virgin oils. arises from the presenceof volatile C,.. alcohols (hexanol. E-2-hexenol, Z-3-hexenol),C6 aldehydesand acetylatedesters.Oils arising from different chemotypescan be distinguishedby headspacegas-liquid chromatography(M. Williams et al., P ht,tochemi str l-, 1998,47, 1253). The dehydrogenaseswhich produce the unsaturatedalcohois have beenstudiedin the pulp of developingolive pericalps(J. J. Salasand J. Sdnchez,Pht'tochemistn',1998, 48, 35). The BP examinationof the oil includesa TLC testfol identity and.to detect foreign oils, the GC determinationof the individual methyl estersof the acidsproducedby hydrolysis.Limits of the principal acids are given above: other percentagelimits, which exclude foreign oils, include saturatedfatty acids of chain length less than C16(#0.1), linolenic(> 1.2),arachidic(>0.7). behenic(>0.2). Therearealsolimits for a numberof sterols.The USP/NF ( I 995) includesspecifictests for the absenceof sesameoil (furfural test),cottonseedoi1,peanutoil and teaseedoil. For the biosynthesisof the acids.seethe introductionto this chapter. The saturatedglyceridestend to separatefrom the oil in cold weather; at I OoCthe oil beginsto becomecloudy and at aboutOoCforms a soft mass.

Cottonseedoil is expressedfr-unr the seeds of varior.rsspecies of (Malvaceae)in Anicrica and Europe.In the UK, Egyptian Gossy1tium and Indian cottonseed.which do not rccluilc delinting on arrival, are largelyused.Seeunder 'Cotton'. The preparationof cottonseedoil i s one of hot crpressionand a pressureof about 10 000 kPa is used.The cnrdeoil is thick and tulbid and is retinedin variousways.that knour.ras 'uinter blcached'beingthe bestofthe refinedgrades.Cottonseed oil is a sentidr1,'ing oil andhasa fairly high iodine value.When usedto adulterateother oils its presence may be detectedby the test for sernidrl,ingoils describedin the ,BP monoglaphfor ArachisOil. The hydrogenatedoil. only, is of1icial.

Uses. Olive oil is usedin the preparationof soaps.plasters,etc., and is widely employedas a saladoil. Oil for usein the manufactureof parenteralpreparationsis requiredto havea lower acid value andperoxide value than that normally required, and to be almost fiee of water' (0.1%) as determinedby the specifiedKarl Fischerrnethod. Recent researchhas suggestedthat olive oil may protect against colonic carcinogenesisby virtue of its action on prostaglandins:rals fed on a diet containingolive oil, as distinct from thosereceiving safflower oil. were protected(R. Bartoli et ttl., Gut,2000, 46, 191).

Macroscopical characters. The seeds are o\ate. flattened and obliquely pointedat one end; about4-6 mm lor.rgand I 1.5 mrn broad. The testais brown, glossyand finely pitted.OdoLrrless: tastc.mucilaginous and oily. If cruciferousseedsare present.a pungentodour and taste may develop on crushing and moistening.A transvelsesection showsa narow endospermand two iar-ec.planoconrex cotyledons.

cocoNuTott The expressedoil of the dried solid part of the endospermof the coconut, Cocos nucifera L. (Palmae)is a semisolid.melting at about 24'C and consistingof the triglyceridesof mainly lauric and myristic acids, together with smaller quantities of caproic. caprylic. oleic, palmitic and stearicacids.This constitutiongives it a very low iodine value (7.0-1 1.0)and a high saponificationvalue. The particularly high proportion of medium chain-length acids means that the oil is easily absorbedliom the gastrointestinaltract, which rnakesit of value to patientswith fat absorptionproblems. Fractionated coconut oil. Fractionatedand purified endospermoil of the coconutC. nut:ifern,or Thin VegetableOil of the BPC, contains

E

LINSEED AND LINSEED OIt Linseed (flaxseed)is the dlied ripe seed of Littttnt Lr.:ir,tti.:sirnutt (Linaceae),an annualherb abotrt0.7 m high qith blue lloriers and a globular capsule.The flax has long been cr-rltivatcdlbr its pericyclic fibres and seeds.Suppliesof the latterarederivedflonr SouthArnerica. India, the USA and Canada.Large quantitiesof oil are erpressedin England.particularlyat Hull. and on the Continent.

Microscopical characters. Microscopicalexaminationof the testa showsa mucilage-containing outer epidcrnris:one or two layersofcollenchyrna or 'round cells': a single la1'erof longitudinally directed elongatedsclerenchyma; the hyalinelal"ersor'cross-cells'composed in the ripe seedof partially or conpletelv obliteratedparenchymatous cells with their long axis at right anglesto thoseof the sclerenchymatous layer; and an innermostlayer of pigment ceils. The outer epidermis is composedof cells, rectangularor five-sided in surfaceview, which swell up in water and becorne mucilaginous.The outer cell walls, when swollen in water. show an or-rtersolid stratifiedlayer and an inner part yielding mucilage. itself faintly stratified. The radial layersor 'round cells'are c.vlindricalin shapeand show distinct triangular intercellularair spaces.The sclerenchyrnatous layer is composed of elongatedcells, up to 250 tim in length,with lignified pitted walls. The hyaline layersoften remain attachedto portionsof the sclerenchymatouslayer in the powdcreddrug (Fig. 12.71).Thepignrentlayer is composedof cells with thickenedpitted walls and containing arnor-

P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO LR I G I N phous reddish-brown contents (Fig. zl2.7H). The ce1ls of the endospermand cotyledonsare polygonal with somewhat thickened walls, and containnumerousaleuronegrainsand -globulesof fixed oil. Starchis presentin unripe scedsonly.

RAPESEED OIt

Refined RapeseedOil EP, BP is obtainedby mechanicalexpressionor by extractionliom the seedsof Bzrssicanapus andB. canpestris. The crop is now extensivelycultivatedin Europeand oils with various propertiesdependingon glyceridecornpositionare commercially Constituents. Linseed containsabout 30-40c/cof fixed oi]r.6Vc of mucilage(^BPswellingindextbr whole seeds< 4.0),257cof proteinand available.As was indicatedon p.8l not all varietiesyield an oil suitsmall quantitiesof the cyanogeneticglucosideslinamarin and lotaus- able fbr medicinalpurposesso that the specifiedpharmacopoeiallimits tralin.Otherconstituents arephenylpropanoid glycosides(L. Luyengi er of the various esterityingacids are important standardsas are relative ul..J. Nat.Protl..1993.56.2012). flavonoids. thelignan(-)-pinoresinol density(c. 0.917)andrefractiveindex (r.. L473). As with someother oils, the additionof a suitableantioxidantis perdiglucoside(a tetrahydrofurofuran-type lignan-see Table22.7) andthe cancer chemoprotectivemammalian lignan precursor secoisolarici- mitted,the nameand concentrationof which must be statedon the label together with a statementas to whether the oil was obtained by (S.-X.Qil et ol., Phamt.Biol..1999,37.l). resinoldiglucoside Cell culturesof Linun albtonareableto synthesize andaccumulate the m e c h a n i c ae l\ p r e \ s i o no r b 1 e x t r a c t i o n . (T. Smollnyara1., lignanspodophyllotoxinand5-methylpodophyllotoxin Pht'tochenisrn,1998.48. 975). SESAME OIt Sesameotl(Gingelly'oil, Teeloil) is obtainedby refining the expressed or extractedoil from the seedsof Sesantumindicum (Pedaliaceae), a herb which is widely cultivatedin India, China.Japanand many tropical countries.The oil is otficial in the EP and BP. The seedscontain about 507c of lixed oil which closely resembles olive oil in its propertiesand which it has, in somemeasure.replaced. It is a pale yellow. bland oil which on cooling to about-zl'C solidifies to a buttery mass:it hasa saponificationvaluethe sameasthat tbr olive oil and a somewhathigher iodine value ( I 04-120). Principal componentsofthe oil are the glyceridesofoleic and linoleic acids with small proportions of palmitic, stearic and arachidic acids.It alsocontainsabott lVc of the lignan sesamin.and the related sesamolin.The characteristic phenoliccomponentis the basisof the BP test for identity and also the test fol the detectionof sesameoi1 in other oils. The originaltest involvedthe productionof a pink colour when the oil was shaken with half its volume of concentrated Uses. Crushedlinseed is used in the folm of a poultice and whole hydrochloric acid containing l7c of sucrose (Baudouin's test). seedsare employedto make demulcentpreparations.The oil is usedin However, some commerciallylefined oils may not give a positive liniments.and researchhas suggested that hydrolysedlinseedoil has Baudouin's test. With the current BP test for the absenceof sesame potentially useful antibacterialpropertiesas a topical preparationin oil in other oils. e.g. olive oil, the reagentsare aceticanhydride,a that it is efl'ectiveagainstSlapftt'lococt:tts drrclr strainsresisrantio solution of furfuraldehydeand sulphuric acid; a bluish-greencolour antibiotics.Linseedcake is a valuablecattlefood. is a positiveresult.The compositionof triglyceridesin sesameoil is determinedin the BP by liquid chr"omatography. those triglycerides having as acid radicalsoleic I part and linoleic 2 parts.and thosehavPAIM OIL AND PALMKERNET OIL ing oieic 2 parts and linoleic I part being among the most predomiPalm oil is obtainedby steamingand expressionof the mesocatpof the nant. fruits of E/aelsguine?nsis(Palmae).World prodLrction amountsto over As statedabove,sesameseedsand oil also containlignans:these I I .5 rnillion tonnes.over half of which is producedin Malaysia.In terms are antioxidants of the tetrahydrofurofuran-type(Table 22.7) and of world consumptionit hasnow overtakensunflowerandrapeseedoils. include sesamin. sesamolinol and sesamolin. Another lignan, Pahn oil is yellowish-brown in colour. of a buttery consistency sesaminol.is formed during industrialbleachingof the oil. The bio(m.p. 30'C) and of agreeabieodour. Palmitic and oleic acids are the logical activities of these compoundsinclr-rdereduction in selum principalestedfyingacids. cholesterollevelsand increasedvitamin E activities.For the biogenPalm kernel oil. Pahn kerneloil is obtainedby heatingthe separated e s i so f s u c hl i g n a n ss e eM . J . K a t o e t a l . , P h y t o c h e n i s t r y . 1 9 9 8 , 4 7 . seedsfbr 4 6 houls to shrink the shell. which is then crackedand the 5 8 3 . kernelsremovedwhole. The oil is then obtainedby expression.It diff'erschemicallyliom palm oil (above)in containinga high proportion SOYAOIL (50%) of the triglyceridesof lauric acid, a saturated.medir-rmchainlength fatty acid (Table 20.2). The mixture of other acids resembles Soya oil is derived from the seedsof Glycine na,r (Leguminosae). that found in coconnt oil. The oi1 is a source of Medium-chain After refining. it is deodorizedand clarified by filtration at about0oC. It shouldremainbright when kept at OoCfor l6 h. The principal esteriTriglyceridesEPIBP. fying fatty acids are iinoleic (41-62%), oleic (19-307c), palmitic Fractionated Palm Kernel Oil BP is pahn oi1which has undergone ('7 14%),linolenic(1-11%)and stearic(1.1-5.55i). selectivesolventfiactionationand hydrogenation.It is a white, brittle Thereis an official limit test for the amounrpf 1[e ,\s.22-24B-methyl solid,odourlessor almostso. with m.p. 31'-36'C making it suitable plant sterol. brassicasterol,which as the name implies occurs in for useas a suppositorybase. Brassicaspp.including B. raptr (c1.v.). Linseed oil. The extractionof linseedoil is one of hot expressionof a linseed meal and the pressis adjustedto leave sufficient oil in the caketo make it suitableas a cattlefood. Linseed oil of BP quality is a yellowish-brown dryin-e oil with a characteristicodou' and bland tastel much commercial oil has a markedodour and act'idtaste.On exposureto air it graduallythickens and torms a hard varnish.It hasa high iodinevalue({ 175)as it contains considerablequantitiesof the glycosidesof unsaturatedacids. Analysesshow linolenicacid,CITH,eCOOH(36-50c/o). linoleic acid (23-21c/().oleic acidClTHr3CooH (10-18%).togethCTTH3TCOOH er with some saturatedacids-myristic, stearicand palmitic (5-ll%). For the fonnation of the unsaturatedacids.seeFigs. 20.1 and20.2. For usein paint.linseedoil was boiledwith 'driers'sr.rch as lithargeor rnanganese resinatewhicl-r.by fonning metaliic salts.causedthe oil to dry morerapidly.Such 'boiledoils'must not be usedfbr medicinalpurposes.

HYDROCARBONS AND DERIVATIVES

THEOBROMA OIt Oil of theobromaor cocoabuttermay be obtainedfrorn the groundkernels of Theobromacocao (Sterculiaceae) by hot expression.The oil is filtered and allowed to set in moulds. Much is refined in Holland. Cocoa butter.as it is commonly termed.consistsof the glyceridesof steadc,palmitic. arachidic,oleic and other acids.Theseacidsare combined with glycerol partly in the usual way as triglyceridesand partly as mixed glyceridesin which the glycerol is attachedto more than one of the acids.It is the most expensiveof the commercialfixed oils and rnay be adr.rlterated with waxes, stearin(e.g. coconut stearin).animal tallows or vegetabletallows (e.g. from seedsof Barsia Longfolia and Stillingitt sebiJera).For the characterand testsfbr purity of oil of theobroma, see the pharmacopoeias. Its melting point (31-3zl') makes it ideal fbr the preparationof suppositories.

The oil should be protectedliom light and oxygen and srorcdar a temperaturenot exceeding25oC.

Eveningprimrose oil The fixed oil frorn the seedsof Oenotheruspp. (Onagraceae) contains substantial amounts of esterified y-linolenic aeid (GLA). a C 1s6,9.12-triene.

ueffioox acid {GLAI 7-Linolenic

cooH Me

WOOL FAT Wool fat (anhydrottslanolin) is a purified fat-like substanceprepared fiom the wool of the sheep,Oulsarles (Bovidae). Raw wool containsconsiderablequantitiesof 'woo1 grease'or crude lanolin. the potassium salts of fatty acids and earthy matter. Raw lanolin is separatedby 'cracking' with sulphuric acid fiom the washingsof the scouringprocessand purilied to fit it lbr medicinal use. Purification may be done by centrifuging with water and by bleaching. Wool fat is a pale yellow, tenacionssubstancewith a faint but characteristicodour.It is insolublein water and a high proportion of water may be incorporatedwith it by melting (m.p. 36-42'C) and stirring. Soluble in ether and chloroform. Like other waxes, it is not readily saponifiedby aqueousalkali,but an alcoholicsolutionofalkali causes saponification. Saponilicationvalue 90-105: iodine value 18-32; acid valuenot morethan l. Hydrouswool fat or lanolincontains25% water. The chief constituentsof wool fat arecholesteroland isocholesterol. unsaturatedmonohydricalcoholsof the formula C27H.+5OH. both tiee and combined with lanoceric,lanopalmitic.carnaubicand other fatty acids.Wool fat also containsaliphaticalcoholssuchas cetyl, ceryl and carnaubl,lalcohols.BLrtylatedhydroxytoluene,up to 200 p.p.m., may be addedas an antioxidant, WoolAlcohoLsEP, BP are preparedby the saponificationof crude lanolin and the separationof the alcohol fraction.The productconsists of steroidand triterpenealcohols,including cholesterol(not less than 30%) and isocholestelol.As for wool fat, an antioxidantmay be added. To testfor cholesteroldissolve0.5 g in 5 ml of chloroform,add I ml aceticanhydrideand two dropsof sulphuricacidl a deep-greencolour is produced. Hy'drogeruttedWooLFat EP, BP is obtained by the high pressure/ high temperaturehydrogenationof anhydrouswool f-at.It containsa mixture of higher aliphaticalcoholsand sterols. Wool fat is usedas an emollientbasefbr creamsand ointments.

Arachidonicacid

Ez(PGEz) E Prostaglandin z(PGEz)

The principal speciescultivateclin thr-UK is O. bieruis which yields an oil containingl-9c/aGLA. althoughrnorclecent work showshigher yields for the oils of someother species.nantelv O. acen,iphilla novct (15.68%),O. porttdo-ra(.l4.4lVc)anclan ccotvpeof O. rubricaulis (13.15Vc).Researchhas involved breedingneu varietiesfor high yields of oil and reducingthe lif'ecyclcof the plant f rorn 14 to 7 months (Pltarm. J., 1994, 252. 189). The sequencefor the formation of such acids in the plant via cislinoleicacidhasalreadybeenindicatedin Fig. 10.l. In animaltissuesit appearsthat the prostaglandinsareformed from dictarl' linoleic acid by conversionto GLA which undergoesCr addition and further desaturation to give acids such as arachidonicacid an inrmediateprecursorof someprostaglandins. The beneficialeffectsof eveningprimroseoil ntar nell be relatedto affording a precunor of the prostaglandinsfbr those individr,ralswhose enzymicconversionof linoleic acid to GLA is delicient.Thc oil is norv widely marketedasa dietarysupplement.for cosnreticpurposes.andmore specifically for the treatment of atopic eczemil and premcnstrualsyndrome(prostaglandin E may be depletedin this condition).Furlherpossibilitiesincludeits usein diabeticneuroDathv andrheumatoidafthritis. Other sourcesof GLA. A number of other seedoil: contain appreciable quantitiesof GLA; theseinclude thoseof Ribesnigrunt andR. rubrum (the black and red currant).Borago of]it'irnli.s(starflower)and S1-mphytum oJlicinale(comfrey).B. offitirtulis is now cultivatedcommercially in the UK to yield an oil containing 25c/cGLA; details of commercial seed production. plant breeding programmesand husbandry will be found in a generalarticle on the crop by A. Fieldsend (Biolo gisr, 1995,42, 203).

Hydnocorpusoil Corn oil

This is the fixed oil obtainedby cold expressionfrom the fresh ripe Corn oil USP/NF (1995),or maize oil, is obtainedby expressionof seedsof Hl,dnocarpuswightiuttt, H. anthelmintica,H. heterophylla the fixed oil from the embryos oI Zea mays L. (Graminae) and and other speciesof Hy,dnocarpus.and also ol TttrtLktogenos kurz,ii. refined. These plants are lbund in India. Bulma. Siam and Indo-China and For the separationof the embryos from maize see 'Preparationof belongto the Flacourtiaceae. Maize Starch'. The refined light golden yellow oil consistslargely of The oil of H. wightianT contains hydnocarpic acid (about 2187c), triglyceridesof the unsaturatedoleic and linoleic acids with smaller chaulmoogricacid (about 21c/c),gorlic and other acids (formulae.see proportionsofpalmitic and steadcacids.Becauseofthe high unsatura- Table 20.4); the structuresof severalnew cyclopentenylfatty acids tion (iodinevalue I l0-128), it is regardedasofvalue in dietsdesigned haverecentlybeenelucidated.Theseacidsdo not appearto be fbrmed to limit blood cholesterollevels. from straightchain acids and they accumulateduring the last 3-4

P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO LR I G I N months of matul'ation of the fluit. They are strongly bactericidal towardsthe leprosymicrococclrs.but the oil has now to a largeextent beenreplacedby the ethyl esterstrndsaltsof hydnocarpicand chaulmoogric acid. The esterifiedoil of H. n'ig,htittna is plefelableto that of other species.in that it yields when fiactionatedalmost pure ethyl hydnocarpate. This was includedin the BPC ( 1965) but has now been deleted.as mol'cef1'e ctivc rcmediesale availablc. Lord Lard (.preparedlartll is the purilied internal fat of the hog, Sus scrofc t o r J e l U n - r : t r l l rS t ru. i t l a rc. For medicinal purposeslard is preparedfi'om the abdominal fat known as 'flare'.from which it is obtainedby treatmentwith hot water at a temperaturenot exceeding57'C. Lard is a soft. white tat with a nonrancidodour.Acid v:rluenot more than I .2.Lard hasa lowermeltingpoint (3,1.11"C) anda higheriodine value (52*66) than suet.Saponification value 192-198.It shouldbe lree fiom moisture.beef'-lat.sesame-seed and cotton-seedoils. alkalis andchlorides. Larcl contains approximately 40c/t.of solid glycerides such as myristin. stearin and palmitin. and 60%, of mixed liquid glycerides such as olein. These fiactions arc somewhatseparatedby pressureat 'stearin'and'lard OoCand soldas oil'respectively.Lard is usedas an ointmentbasebut is no longer of1icialin Britain. It is sornewhatliable to becomerancid. but this may be retardedby benzoination,Siamese benzoinbeing more efl'ectivethan the Sumatravariety.

slow bleachingactionof light. air and moisture.In the lattermethod the melted wax is allowed to tall on a revolving cylinder which is kept moist. Ribbon-like str"ipsof wax are thus formed which are exposedon clothsto the actionof light and air. being moistenedand turned at intervals until the outer surface is bleached.The whole proccssis repeatcdat least once, and the wax is linally cast into circular cakes. Characters. Beeswax is a yellowish-brown or yellowish-white solid. It breakswith a granularfractureand has a characteristicodour. It is insolublein water and sparinglysoluble in cold alcohol,but dissolvesin chlorofbnn and in warm fixed and volatile oils (e.s.oil ofturpentlne). Constituents. Beeswax is a true wax. consistingof about 80% of myricyl pahnitate(myricin),CtsH3ICOOC39H6,. with possiblya little myricyl stearate.It also contains about I5Vc of free cerotic acid, C.6H5rCOOH, an aromatic substancecerolein, hydrocarbons,lactones.cholesterylestersand po1lenpigments. 'drop point' Standards. T'heseincludea of 61-65' for both the white 'ester and yellow wax, value' (q.v.) and 'ratio number' (ratio of the ester value to the acid value) which fbr both waxes lies between 3.3 4.3.

Adulterants, The most likely adulterantsandtheir methodsof detection will be lbund rnlhe Pfurrnrucopoeia. Japanwax, which is there mentioned.is not a true wax but a fat and may be saponifiedby means Suet. Sr.retis the purified intelnal fat of the abdomenof the sheep. ofboiling aqueoussodiumhydroxide.Waxesare saponifiedby strong by aqueousalkali. Ovi.suries.It containsabout 50 60% of solid glyceridesand melts at alcolnLic potash, but are practically r-rnaffected about zl,5"C.It is used as an ointment basc in tropical and subtropical Japan wax is preparedfi'om the tiuits of various speciesof R/rls (Anacardiaceae). countnes. Uses. Beeswaxis usedin the preparationof plasters.ointmentsand polishes.

YELLOWBEESWAX,WHITEBEESWAX Bees',vaxis obtainedby rneltingand puritying the honeycornbof Api,i mellifica and other bees.The wax is imported from the West Indies, Califbrnia. Chile. Africa. Madagascarand India. The EP and BP include separatemono-eraphs for the yellow and the white wax. Preparation, Wax is secretedby worker beesin cells on tht: ventral surfaceof the last four segmentsof their abdomen.The wax passesout throughporesin the chitinousplatesofthe sternumand is used.particularly by the yor.rngworkers.to fbrm the comb. Yellon'beeswa,ris prepared.after removal of the honey.by melting the comb underwater (residualhoney dissolvin-gin the water and solid irnpuritiessinking).straining.and allowing the wax to solidify in suitablernor.rlds. Wltite beesv,uris preparedfrom the above by treatmentwith charcoal.potassiumpermanganate. chromicacid.chlorine.ctc..or by the

CARNAUBAWAX Carnar.rba wax, included tn the EP/BP (2000) and USP/NF (1995), is derived from the leaves of Copernicia cerifera (Palmae). It is removed from the leavesby shaking and purified to remove foreign mattel'. The wax is hard.light brown to paleyellow in colour and is supplied as a moderatelycoarsepowder.as f'lakesor irregularlumps; it is usually tastelesswith a slight characteristicodour liee from rancidity. Esters,chietly myricyl cerotate,are the principal components,with somefree alcoholsand other minor constituents.The acid value is low (BP, USP/NF.2-'7)" Ihe saponificationvalue 78-95. lt has an iodine value of 7-14. Carnaubawax is Lrsedin pharmacyas a tablet-coating agentand in otherindustriesfor the manufactureofcandlesand leather polish. It has been suggestedas a replacementfor beeswax in the p r e p a r r l i oo nf p h l t o c o s r n c t i c s .

PHARMACOPOEIAL AND RELATED DRUGS OF BIOLOGICAT ORIGIN sucrose;it is formed in photosynthesis by the reactionof UDPG with (Fig. 21.3).Control mechanismsfor the build-up fructose-6-phosphate of sucrosein leaves,and its breakdown for tlanspofi to storageorgans, areachievedby metaboliteeffectorcontrolof the appropriateenzymes. The reverse process, hydrolysis. is brought about by suitable enzymes or by boiling with dilute acid. The same sugars may be linked to one anotherin variousways.Thus,the disaccharides maltose, cellobiose,sophoroseand trehaloseareall composedof two molecules of glucosejoined by c,-1,,1-,B-1,4-, B-1,2- and cr,cr-1,1-(nonreducing) linkages,respectively.

HO.^rH

cHo

Y-t

I

HcoH I

HCOH I

HOCH I HCOH

HOCH O

xEox Il t

I HCOH I

CH I

cl-tzoH

cH2oH

Aldohexosc (uglucose)

Aldohcxose (F-p-glucose,showing pyranose ring and the OH taking part in glycoside formrtion)

cH2oH I C=O

Polysocchorides By condensationinvolving sugar phosphatesand sugar nucleotides, polysaccharides are derivedfrom monosaccharides in an exactly similar mannerto the formation of di-. tri-and tetrasaccharides. The name 'oligosaccharide'(Greek oligo, tew) is often applied to saccharides containing from two to l0 units. In polysaccharidesthe number of sugar r.rnitsis much larger and the number lbrming the molecule is often only approximatelyknown. The hydrolysis of polysaccharides, by enzymesor reagents,ofien resultsin a successionof cleavages,but the final productsarehexosesor pentosesor their derivatives.The term 'polysaccharide'may usefullybe takento includepolysaccharidecomplexes which yield in addition to monosaccharidestheir sulphate esters,uronic acidsor amino sugars. Table21.2 indicatesthe characterof someofthe polysaccharides. In addition to the well-establishedpolysaccharide-containing pharmaceuticalmaterialsdescribedlater in this chapterthere is now considerable interest in a number of polysaccharideswith other pharmacologicalactivities.These include immuno-modulating,antitumour, anti-inflammatory,anticoagulant,hypoglycaemicand antiviral properties.Specificexamplesare the glycyrrhizansof Gl.1'cyrrlti:a uralensis and G. gkhra and the glycans of ginseng and Eleutherococurs(q.v.).In generalpolysaccharides from lungi exhibit antitumour activity, those from higher plants are immunostimulatory

6

I

H?O3POCH2^

HOCH I HCOH I

OH

t-l"\^

ffi'"-

HCOH I

cH2oH

O H H uFructose-6-phosphate (furanose ring)

Kctohexose (o-fructose)

_TTN{V* c.H2oH

cr-D-Glucosc (pyranosering)

P->Glucose

OH p-o-Glucose (anotherreprosentation)

F i g .2 l . l Hexose structuresond representotion

cHo

cHo F-oH

cHo Hoi

l-or OH

t -or

-

o-Ribose (pentose)

cHo

Fo'

io* cH2oH

fon

l

f--oH

D-Xylose (pentose)

o-Ribulose (pentose)

H O--l

-i

HO

CHg

Hamamelose r-Rhamnose pentose) (hydroxymethylribose) (methyl

fo' -ot cH2oH o-Mannose (hexose)

D-Xylulose (penrose)

CHeOH I -

cHo

HO

HO

Fig.21,2 Exomples of Cato Cz monosocchorides structures). {Fischer

l-oH

I cH2oH

cHo -.1

cHo

uon,c-f oH

Ho--] I -ot cH2oH

r-oH

cH2oH

o-Arabinose (pentose)

n-n

I

l -ot

cH2oH

CH,OH t -

CH,OH l -

Ho--]

l-o*

t l-on

cH2oH D-Erythrose (tetrose)

cHo lot

HO

l-o'

lI

HO

l-ot

CH2OH o-Galactose (hexose)

Ho---] I -I o H

l-ot -ot

cH20H o-Sedoheptulose (heptose)

CARBOHYDRATES Toble 2l. I

Typ" Di-

Telro'

Some di-, tri- ond ietrosocchorides. Nome

Productsof hydrolysis

Occurrence

Sucrose Glucose,fructose Sugorcone,sugorbeet,efc. Moltose Glucose,glucose Eniymichydrofisisof ,rorch Loctose Glucose,goloctose Mil[ Cellobiose Glucose,glucose Enzymicbreokdownof cellulose Treholose Glucose,glucose Ergot,Rhodophy."o",y"oro Sophorose Glucose,glucose SJphoroiaplnico,6vil.fvri, of srevioside Primeverose Glucose,xylose Fitipendu'to'ulmrrr. fiyarjyri, of spiroein Gentionose Glucose,glucose,fruclose Genfionospp. Melezitose Glucose,fructose,glucose Monno from lorx Plonteose Glucose,fruclose,goloctose Seedsof psylliun spp. Roffinose Goloctose,glucoselfrucfose Mony seeds(e.g.cotton_seed) Monneotriose Goloctose,goloctose,glucose Monno of orh, Fror.irrcornm Rhomninose Rhomnose, rhomnose, goloctose Rhomnusinfectorio Sciliotriose Rhomnose, glucose,glucose Glycosideof squill .. other exomplesof irisocchorides ore omongthe glycosidesol DigitolisondstropAonthus (q.v.) Stochyose or monneoietrose Goloctose,goloctose,glucose,fiuctose Tub-ers'of'Stochys ioponicoondmonnoof rroxrnuSornus Olher exomplesof tekosocchorides ore omongthe glycosidesof Drgilol,s{q.v.)

Uridinc diphosphate glucose (UDp-glucose)

pouredin to form a layerbelow the aqueoussolution.With an insol_ uble carbohydratesuch as cotton-wool (celluiose)the colour will not appearuntil the acid layer is shakento bring it in contactwith phosphstc synlhase I Sucrose the material. (ECz.l.t.tl) [ 3. OsaT.one formation. Osazonesare sugarderivativesfbrmed by heat_ ing a sugar solution with phenylhydrazinehydrochloride,sodium SucroseGphosphate acetateand aceticacid.If the yellow crystalswhich form areexam_ ined under the microscopethey are sutTicientlycharacteristicfor I phosphaore(EC 3.1.3.2a) lSrcrosc certain sugarsto be identified. It should be noted that glucoseand t fructoseform the sameosazone(glucosazone.m.p. 205oC).Before melting points are taken,osazonesshouldbe purified by recrystal_ lization from alcohol.Sucrosedoesnot form an osazone.but under the conditionsof the abovetest sufficienthydrolysistakesplacefbr Fig. 2 | .3 the productionof glucosazone. Biosynthesis of sucrose. 4. Resorcinoltestfor ketones.This is known as Selivanoff's test. A crystal of resorcinol is added to the soiution and warmed on a water-bathwith an equalvolume of concentratedhydrochloricacid. and the algal polysaccharides, which often contain sulphate,are good A rosecolour is producedif a ketoneis present(e.g.fructose,honey anticoagulants. or hydrolysedinulin). 5. Test.forpenloses.Heat a solutionof the substancein a test-tubewith Testsfor corbohydrotes an equal volume ofhydrochloric acid containinga little phloroglu_ The following are some of the more useful testsfor sugarsand other cinol. Formationof a red colour indicatespentoses. carbohydrates. 6. Keller-Kiliani testfor deontszgars.Deoxysugarsare found in car_ 7. Reductiond Fehling's solution. To a heatedsolution of the sub_ diac glycosides such as those of Digitalis and Strophantlra.sspp. stanceadd drop by drop a mixture of equal partsof Fehling,ssolu_ (seeChapter24).The sugaris dissolvedin aceticacid containinga tion No. I and No. 2. In certaincasesreductiontakesplacenearthe trace of ferric chloride and transferred to the surface of concen_ boiling point and is shown by a brick-red precipitateof cuprous tratedsulphuricacid.At thejunction ofthe liquids a reddish_brown oxide. Reducing sugarsinclude all monosaccharides, many disaccolour is producedwhich graduallybecomesblue. charides(e.g. lactose,maltose,cellobioseand gentiobiose).Non_ 1. Enzyme reactions.Since certain carbohydratereactionsare only reducing substancesinclude some disaccharides(sucrose and brought about by certain specific enzymes,such enzymesmay be trehalose,the latter a sugarfound in somefungi) and polysacchar_ usedfor identification. ides. Non-reducing carbohydrateswill on boiling with acids be 8. Chromntograpfty.Chromatographic methodsare particularly suitedto convertedinto reducing sugars,but studentsare remindedto neu_ the examination of drug extracts, which may contain a number of tralize any acid used for hydrolysis befbre testing with Fehling's carbohydratesoften in very small amounts.Not only are they applica_ solution,or cuprousoxide will fail to precipitate. ble to carbohydratesoriginally present in the plant, but also 2. Molisch's te.st.All carbohydratesgive a purple colour when treated they may be used to study the products of hydrolysis of polysaccha_ with o-naphthol and concentratedsulphuric acid. With a soluble ride complexessuchasgums and mucilages.As standardsfor compar_ carbohydratethis appearsas a ring if the sulphuric acid is gently ison many pure sugars,uronic acids and other sugar derivatives are

Fructose Gphosnnate !

N uop I

l\- n su.L."

ORIGIN OF BIOLOGICAL DRUGS AND RELATED PHARMACOPOEIAL

Tqble 2I.2

The -^ I ll \-\

b \

3-Butylphthalide

L\-^ I ll \-\

b \

Ligusticum lactone

4-'Y'\ l i l

x

p n

I idr rc+ili.i6

The plant is native to southernEurope.westernAsia and the Orient bLrthas fbr a long time beencultivatedelsewhere:it is producedcomOH rnerciallyin the Balkans,Germany,Holland, Polandand the USA. In habit, lovage is a tall, aromatic perennialherb with bipinnate. caulineleavescoarselytoothedat the apex and greenish-yellowflowers. The rhizomesand roots are obtainedfrom plants 2 to 3 yeals old and when split. cut and dried are in piecesup to 5 cm in diameterfor the rhizomes and up to 25 cm in length for the roots. Externally the drug is greyish-brownin colour and longitudinally furrowed: a transversesectionofthe roots showsa thick yellowish-whitebark separated o fiom a brownish-yellowradiate wood by a dark line. Oil-containing Absinthin Artabsinolide C structLlresare visible in the outer regions of the transversesection. Artabsinolide A = 2-ketone Microscopic charactersof the powdered drug include polygonal or B = 4-epimer, 2-ketone Artabsinolide roundedcolk cells as seenin surfaceview. considerableparenchyma, vessels.fiagrnentsof secretorycells and single reticulately-thickened The plant is a subshrubwith deeplydissectedleaves.The insignifi- and compoundstarchgranules. cant globoset-lowersform loosepaniclesand consistmainll' of tubular' The drug containsup to l.Oolcof volatile oil, the characteristicodorl-loretsand a few ye1lowray florets.The leavesand groovedstemsare if'erouscomponentsbeing alkyl phthalidesof which 3-butylphthalide coveredwith silky hairs. (c. 32%),ligustilide (c. 24c/r''l and ligusticumlactoneareprincipalcomCharactelisticfeatr.ues of the microscopyarethe T-shapedtrichomes ponents.Terpenesinclude a- and B-pinene,a- and B-phellandrene.a(Fig. 43.3I) on both leaf epidelmi: thesehaveuniseriatestalksof up to and B-telpinene, camphene, myrcene. etc. Other constituentsale heads.Thereilre numerousuni- various coumarinsand plant acids.The BP includesa TLC examinathreecells and long taperingur-ricellular cellular long, twisted trichomesand secretorytrichomeswith biseriate tion as a test for identity and fol the absenceof angelicaroot. two-celledstalksand headsof two to fbur cells.The storrataare of the Lovage has been used for centuries as a herbal remedy. It has anomyocytictype. Numeroussphericalpollen grains.30 pm in diame- carminative,diuretic and antimicrobialpropertiesmaking it uselul lbr ter with threeporesand a spiny exine.ale seenin the powdereddmg. the ffeatmentof dyspepsia,cystitis and as a mouthwashfor tonsillitis. The drLrghas an aromaticodoul and is intenselybitter. The active Herbalistsusuallyplescribeit in admixturewith other drugs. and essentialoi1.Bitter substances constituentsarethe bitter substances (0.15-0.4%) consistof sesquiterpene lactones,principally the dimeric Tonsy guaianolideabsinthin(0.20-0.28tlr).artabsin,artabsinoiides A. B. and Tansy (.TanatetLun (L.) Bernh.) vulgare (L.): Chrt,santhenumvuLg,are test lbr C and others.They are evaluatedin the BP by the or-eanoleptic (Compositae)is usedas an anthelminthicin herberlmedicinebut its poi'bittemessvalue' using a quinine hydrochloddesolution for comparisonous properties are well appreciated.The herb contains about son.The essentialoil (BP lequirementnot lessthan 0.2(/c)is variablein 0.2-0.6Vo volatile oil containing around 707c of thujone. Many compositionaccordingto geographicalsourceand chernotypewith any sesquiterpene lactoneshave been isolatedliom the flowers and herb and chrysan- togetherwith f'lavones.Numerouschemicallaces,originatingfrom difone of p-thujone,/rurs-sabinylacetate,r'i.i-epoxyocimene thenyl acetateforn-ringover 407r ofthe mixture: alsopresentare other felent geographicalareas.are known and involve both the oil consesquiterpenes andmonoterpenes. (For a seriesof reportsinvolving three stituentsand the sesquitelpenes. Orer the years many medicinal ploperties have been ascribeclto other speciesof Tirruu:etum see O. O. Thomas,Fitoteropia, 1989.60, wormvn'ood. lt is consideredof value fbr pfomoting the appetite,for its 138,231, 329 and leferencescited therein.With regard to the antistrcngtheningefl'ectin the treatmentof colds and influenza.for gall inflarrmatoly properties of the herb, C. A. Williams et al. bladdcrand menstrualproblemsand for the expulsionof roundworms. (Phvtochentistn 1999,51,417)havecomparedthe f-lavonoids of T. t'ulThujoneis toxic. making the cultivationof low-thujunechemotypes gare andf'everf-ew. and revisedsomeflavonoidfolmLrlae.) The herbis alsousedin the makinsof licueurs. desirable.

LOVAGE Lovage is the whole ol cut dlied rhizome and root ol Levisticumolficifarnily Urnbellifelae.The oflicial drug nale (.Ligustic'untlev'istictttn). shouldcontain not lessthan 0..17cessentialoil for the whole drug and not less than 0.3% fbr that in the cut condition calculatedwith ref'erAlthough oflong-standingrecognitionin a enceto the anhydrousdr-Lrg. number of European pharmacopoeiasit has not previousiy been includedin the BP.

Sondolwood oil Sandalwoodoil is obtained fiom the heartwood of Suntalmnttlbmtt (Santalaceae). an evergreentree 8 12 m in height which is widely distributedin India and the Malay Archipelago. Supplies are mainly derived liom Indonesia and southeln India where the trees are systematicallycultivated and the cutting is controlled. The volatile oil is containedin all the elementsof the wood. rnedullaryray cells. vessels.wood fibres and wood parenchyma.The alcohols,distinguishedfor oil containsabout90-977cof sesquiterpene purpose of analysis as 'santalol'. This consists of o-santalol (b.p.

V O L A T I LOEI L SA N D R E S I N S 300-301"C)and B-santalol(b.p. 170-l7l"C). The hydrocarbontraction containsabout nine components.Recentleports sllg-sestthat the oi1is being adulteratedwith polyethyleneglycols.The oil is now mainly usedin perfumery;a possiblechemoprotective actionon liver car'(S. Banerjeeet al.. Cancer cinogenesis in mice hasbeendemonstrated Lett., 1993.68, 105).Alstttlittn .srmtlalwoorl oil is preparedby distillation and rectificationfiorn the wood of Eucan'a ,spicatu,a small tree growingin WesternAustralia.It containssesquitelpene alcohols.

{

p()\\c\\ in thc Collection. Alrlost all membersof thc Burserirceilc phloem olcoresincanals.which are lbrmed schizogcnourlr antl ntar allerwaldsunite with one anotherto fbrm schizolvsigcrtou\ r'r\ iriL-\. This occlrls in the speciesCornniphoru. Much ol' the secrction is obtainedby spontaneous fiom the cracksand fissure:$ hich exudittiorr commonlyfblm in the bark.and someis obtainedfiom incisionsnrade by thc Somnlis.The irellowish-white. viscousfluid soonhaldcnsin the greatheatto reddish-brownmasses.u'hich arecollectedby the Sonralis, As bdelliumsand gums are collectedat the sametime. thescfi'equentlr find their way into the drug and have subscqucntlyto be pickedoLrt.

Copoibo Copaibais an oleoresinobtainedf}om the trunks of variousspeciesof Copnifera (Leguminosae)and contains at least 24 sesquiterpene Characters. Myrrh occurs in somewhat irregular tears or masses hydrocarbonsand a number of diterpenes.It was fbrmerly used as ir weighing up to about 250 g. The surfaceis reddish-brownor reddishyellow in coloul and powdery.The drug fl'acturesand powdersreadily. urinary antisepticbut has now been almost completely replacedby r n t i b i o t i c \r n d o t h e rd r u g s . the freshly exposed sr-rrface being of a rich browr.rcolour and oily. Whitish marks are sometimesseenand thin splintersare translucent. Myrrh has an aromaticodour and an aromatic.bittel and acrid taste. Eriodictyon leof Myrrh fbrms a yellowishemulsionwhen tlitr.ratedwith water.When Eriodictyon or Yerba Santaconsistsof the dlied \eaf of Eriotlir'h'on (Hydrophyllaceae), zrlow evergreenshrubof the hills and cxtracted with alcohol (907c), as in the preparationof Tincture of cttlifornicLut't Mvrrh, a whitish massof gurn and impr.u'ities remains.The ,BPalcoholmountainsof Califbrnia and northernMexico. The lea'n'es usuallyoccur in fiagments;when entirc.thcy arc lanceo- irrsolublematter should not exceecl7\c/r,.Lunp myrrh usually yields late.5-15 cm long and l-3 cm wide. The apexis acute:the baseslightly not more than 57cof ash.but the cornnrercialpowdereddrug f}equentfrorn perfumed bdellium and taperinginto a shortpetiole.The margin is inegularl-vsenateor crenate- ly yields nrore.It rray be distingLrished dentate.The upper surfaceis yellowish-brownto greenish-brownand sirnilar p|odr.rcts by allowing an etherealertract of the dlug to evapocoveredwith a glisteningresin.The lowel surfhceis gleenish-greyto rate to drynessand passir-rg the vapour of bronrine over the resinous yellowish-grey,conspicuouslyreticr.rlate, with greenish-yellowor fihn ploduccd.A violet colour is given bv genuinemyrrh but not by brown veins, and minutely tomentose(coltony) betwccn thc reticula- bdelliurn. TLC and visualization n'ith ultraviolet light at 365 nm is tions.The leavesarethick and brittic. They have an aromaticodour and usedby the BP as an identificationtestan.l alsoto establishtl'reabsence of C. ntukul.an inf'eriorbdelliurnproduct. a balsamicbittertaste.which becomessweetishand slightly acrid. 'Hespelidin' Eriodictyoncontainsvolatile oil, resin.eriodictyol(see xanthoeriodic- Constituents. Myrrh contains 7 17c/aof volatile o11.25-10% of and'Eriodictyol').homoeriodictyol. chrysoeriodictyol. 'gum' resin.57 6lc/cof and some3 47c of irnpurities. tyol, eriodonol,eriodictyonicacid and ericolin. Yerba Santais employed in the USA fbr the prepalationof a fluid T h e r o ] l t i l e o i l c o n t u i n rt e r p e n e s: e . : q t r i t e r p e n ees\.t e r \ .c u m i n i c fraction contains furaextract and Aromatic Eriodictyon Sylup, which is used to mask the aldehyde ancl eugenol. The sesqr.rilerpene furanoguaianes nosesquiterpenes including furarrogermacranes, and tasteof bitter and otherwisedisagreeablemedicincs,particulally quiFuraneudesrna1.3-dieneand curzarenchave mornine.AmericanIndianssmokedol chewedthe leavesas a cure lbr asth- furanoeudcsmancs. phine-like propertiesanclact on the CNS opioiclreceptors:firranodima. Someherbalistsconsiderit an excellentexpectorant.Extcrnally it ene-6-oneand methoxy furanoguaia-9-cne-8-onc show antibactcrial can be usedfbr the treatmentof brr-rises. insectbites"etc. and antifungal activity againststandardstrainsof pathogenicspecies (P.Dolaraet al.. Nuture,1996,379,29', PlantaMetlit:a.2000,66.356). MYRRH The oil. whichis distilledoutsidethecountriesololigin. readilyresiniMytth (Arabian or Sont.aliMyrrhl is an oleo-gumresin.obtaincdfrorn fies and then gives a violet colour with bromirre. growin-ein The chemistly of the resinsis complex and not fully elucidated.The the stemof variousspeciesof Cr.tntntiplnru(Burseraceae). portion containso-, B- and y-commiphoricacids, nofih-eastAfrica and Arabia. British texts have traditionallygiven the larger ether'-soluble principalsolrrceas C. molmolbut Tucker(Econ.Bot., 1986,40..12-5) the estersof anotherresin acid and two phenolic resins.The smaller statesthat the chief sourcetoday is C. tnyrrho.The EP and BP definition cites Contmiphora molmol Englel and/or ot.her species of Contniphora. Two other species.C. abyssinic'attndC. sc'ltinperr,both of which may attain a height of l0 m. grow in Alabia and Abyssinia. The drug is chiefly collcctedin Somalilandand Ethiopiu.

i I

t

History, Productsof the myrrh type were well known to the ancients under the namesof bola. bal. or Do1.The drug is still known to the l n d i a n t r a d e r sa s ' h e e r a b o l ' .w h i l e t h e S o m a l i sc a l l i t ' m u h n u l ' o r 'ogo'. The name'myrrh'is plobnbly delived from the Arabic and occur in the Hebrew word rnur, which meansbitter. Many ref'erences Old Testament,but the product was apparentlythat derived fiom C. 'habbak ertlq'aea var. glabrescens.which is known to the Somalis as hadi'. and commerciallyas perfumedbdelliLrmor bissabol. Guban rnyrrh, which is producedfrom the treesof the Somali coast areaknown asthe Guban.is ratheroily and is regardedas inf'eriorto the more powdery'ogo' prodr"rced furtl-rerir-rland.

Furaneudesma-1,3-drene

Curzarene

tvte

o F ur a n o d i e n e - 6 - o n e

'""

M e t h o x yf u r a n o g u a i a - 9 - e n e - 8 - o n e

E

LR I G I N P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO Constituents. Asafbetidaconsistsof volatileoil. resin,gum andimpLrrities.The oil hasa parlicularlyevil smellandcontainssnlphurcompounds of the fbrmulaeCTH1+S.. Cl6H20Sr, CitHl65,,Cl0Htils2.C7H1aSj.and CrH,,,Sj; someof theseshow pesticidalactivity.The f-lavouris largely due to R-2-butyl-l-propenyldisulphide(a mixtureof E andZ isomers).l'bdelliurn' disulphideand 2-butyl-3-methylAllied drugs. Four ditl'erentvarietiesof were recognized ( l-methylthiopropenyl)-1-propenyl The dnrg also by Holmes.Of these.parlirntetlor',scented bdelliuntor bis,sabolis prob- thioallyldisulphide(bothasmixturesof diastereoisomers). umbellif'erylethersmostly lt resernblessoft myrrh containsa complexmixture of sesquiterpene ably derivedfionl C. entltaeu v'r,r.glabrescen.r. in appearance but is easily distinguishedfrom it by the more aromatic with a monocyclic ol bicyclic terpenoidmoiety: more recently (G. odor.rrand by the fact that it does not -eivea violet colour with the Appendinoet a1.,Ph1'tochemis/ry. I 994.35, I 83) threenew sesquiterpene coumadnethershavebeenisolated.Also presentare asaresinolf-erulate bronrinerc{. Hotdi bdellium or gurn hotai is opaqueand odourless;it and free ferulic acid.The dlug containsno liee umbellif'erone(distinction containsa saponinand is usedlbr washingthe hair. fiom galbanum). However, on boiling it with hydrochloric acid and a blue f'luorescenceis produced owing to the Uses. Myrrh is used in incense and perfumes. Like many other filtering into an-m'ronia. of umbellif-erone. Ferulicacidis closelyrelatedto umbellicacid resins. it has local stimulant and antisepticproperties.It is chiefly fbn'rration (bothof which occurin galbanum). ernployedin medicirrein the lbrm of a mouth-wash.For researchon the andurnbellif'erone positivegastricantiulcerand cytoprotectiveeffect of myrrh on treated rats and for referencesto other reports see M. M. Al-Harbi et al., J. Etlutopharm..1997,55, 1,+1. o'aoo,

acids.The ether-insolublefractioncontainso.-and B-hecrabornyrrholic crudealcohol-insoluble matter('glrm')containsabout I8clr,of protein and 64%' of carbohydratecontaining galactose,arabinoseand gluwith an oxidaseenzyme. curonicacid.This gum is associated

nof\

Olibonum

?.r.

cooH

U.rA'

V\crcH

Olibanum (.Frankincense) is an oleo-gum-resinobtained by incision H H f}onr the bark of Boswellia cttrterii, B. frereana and other speciesof Umbellicacid Ferulicacid to nofih-eastern Africa Boswellitt(Br.rrseraceae), small treesindi-eenous (dihydroxycinnamic (hydroxymethoxyandArabia.The drug occursin more or lessovoid tears.5 25 mm long, acid) cinnamicacid) which are sometimesstuck together.The surfaceis dusty and of a yellowish, bluish or greenishtint. Fracture,brittlel inner surtace,waxy and semitranslucent. Odour is characteristic, especiallywhen burned:taste. slightly bitter. The drug contains 3-8% of volatile oil consistingof H about60-70% numerousterpenes(e.g.p-cymene)and sesquiterpenes. of resin.and27-35c/aof gum. In I 956 the gum wasfbund to containtwo Umbelliferone polysaccharides; one consistingof units of galactoseand arabinoscand (lactoneof umbellic the other of galactoseand galacturonicacid. Olibanum is used irr acid) incenseand fumigating preparations.Former'1y.it was considereda stimulantand hasbeenusedin China for the treatmentof leprosy.With ' animal models, Duwiejua er al. (.PlantaMedicu. 1993, 59. 12) have Allied drugs. Galbanum and ammoniacum are oleo-gr.rm-resins obtained,respectively.from Ferula gulbtutiflua andDorema antntortireporteda positiveanti-int-lammatory activity tbr the drug. acum. Galbanumcontains,besidesumbelliftrone.a number of umbelliferone ethers; also gum and up to 307c of volatile oil containing Asofoetido nlrmerousmono- and sesquiterpcncs. azulenesand sulphur-containing Asafoetidais an oleo-gum-resinobtainedby incision fiom the living rhizome and root of Ferula Jbetirla Regei, F. rubricattlis Boiss., and esters.Ammoniacum.listed in the BHP. containsfiee salicylic acid but other speciesof Ferula (Umbellif'erae).plantsabout3 m in height.The no urnbellif'erone.The major phenolic constituentis ammoresinol: Appendinoer ul. (.Helt'.Chint Aoa, l99l ,74,495) isolatedan epimeric drug is collectedin Iran, PakistanandAfghanistan. mixture of prenylated chromandionestermed ammodoremin. The Collection and preparation. The collection of asafbetidainvolves volatile oil (c. 0.5%) containsvarious terpenoidswith f'eruleneas the removalof the stemand the cutting of successiveslicesfion'rthe verti- major component. cal rootstock.After eachslice is removed,oleo-gum-resinexudesand. rlhen sufflciently hardened,is collected.The productis packedin tin- Uses. Asafoetida is included in the BHP (Vol. 1, 1990) and is employedfbr the carrninativeand expectolantpropertiesof the volatile linedcasesfor export. oil fiaction. It is an ingredientof certainsauces. Characters. Asalbetidaoccursin two principal forms. kzu's. These are rounded or f'lattenedand about 5-30 rnm diameter. Dqmiqnq They are srevish-white.dull yellow or reddish-brownin colour, some Darnianaconsistsof the dried leavesof Ttrmeradiftilsu tar. aphrodisiaandprobablyotherspeciesofTuntera.The dru-{is colspecinrensacquiring the latter colour with age. while others remain ca (Tumeraceae), lectedin Bolivia andMexico. The leavesareyellowish-greento greenin greyishor yellowish. Mas,i. This consistsof similar tears to those describedabove colouq broadlylanceolate.shofily petiolate.and 10-25 crn long: margin with 3-6 teethon eachside; veins pinnateand prominenton the lower agglutinatedinto massesand usually mixed with fruits. flagments of root, earth and other impurities. Mass asafoetidais the commonest surface.The drug usuallycontainssomeof the reddish-brown.cylindrical twigs, flower"sand sphericalfruits. Darnianahas an aromaticodour commercialfbrm. and taste.lt contains0.5-1.0% of volatile oil, frorn which thyrnol. aAsafbetidahas tr strong.alliaceousodour and a bitter.acrid and allicopaene,8-cadineneand calamenenehave beenisolatedlin addition.a aceoustaste.It shouldyield not more than 50Vcof matterinsolublein brown amorphoussubstance, damianin,resinsandgum. alcohol (907r,)and not more than l,5clrof ash.

toFao-g=o V\.rt'

V O L A T I LOEI L SA N D R E S I N S It u'ould appenrthat in Merico the wild populationsof the plant are Sandalacoccursin small tearsabout0.5-1.5 cm in length.Theseusuthreatencdb_vover-collection.and cultil,ation is recommendedusing ally har,ean elon-qated. stalacticor cvlindrical shape.globular or pearmicropropagation. the lanerhavingnow beensho'"',,n to be a commcrcial shaped tears being relativell' ralc. The sulface is coveled with a (L. Alcaraz-Mcllndeter ul.. Plurt Cell Rep..1994,13.679.1 yellor.vish f'easibility dirst.but the interioris moreol lesstransparent, andif thetears ale held up to the light. smallinsectscanfiequentlybe seenernbeddedin Uses. Damianais traditionallvusedin Mexico and SorllhernUSA to thern.The drug is easily powderedand when chewed remainsgritty. rer"ivclibido whercsubconscious causatir,c fhctorsalc inr,olved.Elixir showingno tendencl'to form a plasticn'rass(distinctionfiom mastic). of Dilrliana and Saw Palmetto or other aclmixturesare used as an The drug hasa tnint. terebinthinate odour.and a somewhatbittertaste. aphroclisiac fbr mcn. Sandaracresinconsistsof sandarocopinaric acid (inactivepimaric acid). sandaracinicacid. sandaracinolicacid and sandaracoresene. The Gomboge drug alsocontainsa bitterprincipleand0.26-1.37cofvolatile oil. Gambogeis a gum-resinobtair-red from GurcirtiuhtLnburii(Guttif'erae). a trce inclisenous to South-East Asia. Grindelio herb Gambo-qeis a tvpical -9um-r'esin. and when tritr,ratedwith r.vater'. it Grindeliao[ gum plantconsistsofthe driedleavesand lloweringtops tbrrnsa vellovn, emulsion.Good gambo-recontains10 80% of r.esin of Grindelia cotllporlotl (G. robusta). G. humili.s and G. squarrosa (gambogicacid)and l5-20% of water-soluble gum rvithwhich is asso- (Compositae).collectedin south-westernUSA. The plants are herbaciatedan oxidaseenzyme.Gan"rboge actsas a purgativebut is now lit- ceous with cylindrical stems, sessile or amplexicar-rlleaves. and tle uscdin hurnanrr-rcdicine. It is usedas a oiqment. resinousf-lower-heads eachsurroundedby an involucreof linear-lanceolate bracts.Odour.balsamic:taste,aromaticand bitter. Mostic In the wild 2n andhl fbrms occur and selectionof the latter for cul\'[asticis a resin.or rnorecorrectl],anolcoresincontaininglittle oil. ti\rationshouldproducehigheryieldsof resin(J.L. McLaLrghlin et al., obtainedfrom a cultivatedl.aliety of Pistacia !entistLtsvar. t:hicL Eton. Bot. 1986.40. I -55). (Anacardiaceae) in theGreekislandofChios.The plantis an evergreen Grindeliacontainsabout20% of resin.which containsa largenumdioeciousshrr-rb. ber of labdanediterpeneacids tenned grindelanesand methyl esters Tappingis limited by law to the period l-5Jul1,-l-5Ocrober.The base (seeB. A. Timmermannet ul., Pht'tochenistry.1985,24. 1031:M. of the shlub is clealc-dof rveeds.flattenedand cor,eredwith a special Adinolli er al.. ibid.,1988.27. 1878).The plantsyield abour0.2% of a rvhitesoil to receivesomcof the tlow,.The stentand largerbranchesare volatileoil containingover 100components. Oil compositionfiom the thcn woundedby nreansof a gouge-likc irrstlurnerrtw,hichmakesan di11'erent speciesvariesquantitativelywith bornyl acetateand u-pinene incisiorrabout2 cnl long and 3 mrn deep.Eachplantis tappcdrepeated- the rr-rajorcomponents of the monoterpenoidfiaction (see G. lv lbl about-5or 6 rveeks.rcceivin-Q in all about200-300 wounds.A spe- Kaltenbacher ul.. PlantaMetlicn.1991,57. (Suppl.2), A82). cial tool is r-rsecl fbr rentor,ing thc tearsrvhichhardenon the plantandthe The herb has been usedtbr the treatmentof bronchitisand asthma. f'latplatesof ntasticr.l'hichcollect on the ground.Thesearegradedby the but is now mainly employedin the folrn of a lotion tbr dern-ratitis procollectorand regraded.n'ashedand dried in a centraldepotbefbrcbeing duced by the poison ivy, R/ias to.rit:odendron(Anacardiaceae). Some exportedin wooclenboxcs.Chiosexportsabout250 000 k-r annualll'. grindelaneshave been shown to have antifeedingdeterent activity Nlasticoccursin yellou,,or'-treenish-yellowroundedor pear-shaped towardsaphids. tearsabout3 mm diameter'. The shapeof the tearsis sufTicientto distinThe tearsarc blittle but becomeplas- Guqiocum resin -tuishthen fiom thoseof sandarac. tic whenchewed.Odorlr.slightlybalsanric:taste.rnildly telebinthirrate. Gr-raiacunr resin is obtainedfiom the healtwood of GuuincuntffitiThe resincomponentof mastic is a complexmixture.It containstri. nale and G. suttt:tLutt (Zygophyllaceae).small evergreentreesfbund in tetra-andpenta-cyclictriterpcncacidsanclalcohols(fbr a lepor-tseeF.-J. the dry coastal regions of tropical America. Gutticrcuntoffit.inale is Marrrere/ rr1..Plr'tochentistrt'. I 991.30.3790).About2% of volatileoil is fbund on the coastof Venezuelaand Colombia and in the West Indies. alsopresent:over 60 cor.npounds havebeenreportedfrorn masticanclup while G. sotlctlull occurs in Cuba. Haiti. the Bahamasand Flor.ida. to 2-50rccordedin plant oils. The principalcomponentsappearto bc the Little is now found in comrrerce. monoteryenehydrociubonscr-pinerre.B-myrceneand camphene.Four Guaiacumresin occurs in large blocks or roundedteals about 2-3 ncutralnoveltritcrpenoidsandtcn triterpenoidacidshavenow beenchar- cnr diameter.The freshly fractured sulface is brown and glassy.The acterized. seeV P.Papa-{eolgiou et aL..J. Chrcmar.A.l99l ,769. 263.The powder is greyish but becomesgreen on exposul'c.Taste.somewhat aciclvah-re of about50 (BP. 1980.not mole than70) distinguishes it tiorn acridl odour,when warmed.aromatic.When ll'ee fi'om woody debris. EastIndianor Bcxrbaymastic.$'hichhasan acidvalueof morethan 100. guaiacumis solublein alcohol,chloroforrnand solutionsofalkalis.An Mastic is r.rsecl in thc prepal'ationof ComporlndMastic Paint and ls ir alcoholic solution gives a deep bh-recolour (guaiac-blue)on the addmicroscopicalnroLlntant. ln Gleeceand the MicldleEast mastichas ition of oxidizing a-Qentssuch as f'crric chloridc. This colour is been r-rsedfbl centr.r.iesas a pfotecti\,ea-centfbr the stontach.and destroyedby reducin-qa-eents. Colophurv. the most likely adulterant, investigations at theUnivelsitvof NottinghamMedicalSchoolindicat- may be detectedby the cr.rpricacetatetest. ed successin the tlcatmentof -eastriculcers.Researchl-rasshown that Some of the rnain resinousconstituentsare lignans.Theseare phemastic \\,ill kill Helicobttcter pthtri at concentrationsof 0.06 mg/ml nolic compoundshaving a C1gstructureformed fiom two C6-Cj units (sccF. U. Huwcz eI al.. Nen Dt,ql.J. Mcd.. 1998,339.l9'16).Further (Table 22.1). Guaiaretic acid. which forms about l\Vc oI guaiacr.rm studiesare no',vplannedu'ith paticnt volunteersinf'cctedwith H. pt'lori resin.is a dialyl butane. (.Plturnt../.. 2000.264, 159). The f-lowels.fruit and bark ofthe tree containtriterpenoidand nortriterpenoidsaponins. Sqndqroc For use as a reagentthe resin as extractedfiom the wood by means Sandaracis a resin obtained fi'orr-rtl-restem of Tetruc.lini.s urti(Lrlota of chloroforn is saidto be the most sensitive. An alcoholicsolutionis (Cupressaceae). a tree 6-12 rn high. rvhich is fbund in North and usedfol the detectionof blood stains,cvanogenetic glycosides.oxiNorth-'uvest Atiica and in Spain. daseandperoxidase enzymes.

E

P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AO LR I G I N Guaiacumresin, included inlhe BHP (Vol. 1. 1990)is indicatedfbr the treatmentof chronic rheumaticconditions.lt is a permitted lbod additivein the USA and in Europe. lpomoeo Ipomoea(Oriz.abaJalalt. Me.ricurrScutunonl'Root)is the dried root of (Convolvulaceae). Ipotnoectorizaben.\i.\ a convolvulaceous twining plant with a fusifornr rcot about 60 crn long. The drug is collectedin the Mexican Statcof Orizabaand is exportedfiom VeraCruz. Orizabawas ori-einallvirnportedas a substituteor adulterantofjalap or its resin('jalapin'1.Hou'ever,the resinis more solublein etherthan isjalapresinlnd morecloselyresernbles thatobtainedfrornthe root of (lottvolt'trltr.s .sctuunrtntia. rvhich was the original sourceof scammony resi n. Wholc rootsof ipomoeaarerarelyinrporled.andthe drug usualiyconsistsof transverse or obliqueslicesabout3- I 0 crn wide and2-4 cm thick. Thc outersurfaceis coveredwith a greyish-blown.wrinkledcork.The trans\,crsesudaceis greyishor brownishand showsabout3-6 concentric rings of fibrovascularbr.rndles. The parerrchymatous tissueof both bark and steleresemblesthat ofjalap in containingstarchand calciunl oxalate.Likejalap, the sectionshowsnumeLousscatteredsecretioncells with resinouscontents.Odour.slightl taste.f'aintlyacrid. Ipomoea,when extractedwith alcohol (90%,).yields about l0-20% of a complexresinousmixture. of which about6-57cis solublein ether. The chief constitllentsof ipomoearesin are the rnethylpentosidesand other glycosidesofjalapinolic acid and its methyl ester:theseare the orizabins.Also isolatedare the scammonins. the stnlcturesof which are indicated below. For details of these resin glycosides see B. Hern6ndez-Carlos et ul., J. Nat. Pntl., 1999,62, 1096.Aiso presentare glycosides. sitosterolandotherphytosterol Ipomoea is mainly used lbr the preparationof ipomoea resin. lt jalap in medicinalproperties. resernbles Jolop Jalap consists of the dried tuberclesor tuberous roots of lpomoea pLtrga,a large,twining plant indigenor-rs to Mexico. Most of the drug is 'Mexican' 'Vera imported from easternMexico under the name of or Cruz'jalap. Convoivulaceous tuberswith purgativepropeltiesu'ere blought to Spainabout 1565. The traditionalsystemof productionin CentralVera Cruz has been describedby A. Linajeset al. (Econ.Bor.. 1991,48,8;1).Scarification of seedsprior to sowingis the secretof obtaininga 957r germination ratein 8 days.The productiveperiod extendsfi'om JuIy to Februaryand the harvestedtubers are smoke-driedin small wooden sheds using unseasonedLiquitlamber ntacrophvlla wood fbr tuel. During this processthereis a weightlossof 50-l5c/r,.This methodgivesa product more resistantto fungal and insectattackthan doessimpledrying. The which canbe increased, asin i"ieldis 2.4-3.0tonsoffresh root/hectare India. to ,1.8tons/hectareby the use of cow trranure. Jalap tubercles ale fusifbrm, napilbrm or ilregularly oblong in shape.and 3--5cm long. They are extremelyhard and heavy.Thc surfhce is corered u'ith a dalk brown. wrinkled cork. which is marked with lighter-coloured. lenticels.The largerpiecesmay bear transverse gashes.rvhich have been made to facilitate drying. The tr.rbercles may be softenecltbr cutting by prolongedsoakingin water.Cut transversely they show a -rrelishinterior.a completecambiumring fairly closeto the outsideand within it numerousirregulardark lines. The dlug has a slight, smoky odour: the tasteis at first sweetish,aiterwardsaclid. A descriptionof the microscopyofjalap was given in the 1ith edition. Jalapcontains9-l 87 ofresincontainedin secretion cellsandgiving a yellow stain with iodine water. It may be extractedfrom the powdereddrug with boiling alcohol(90%).On pouringa concentrated tincture into water, the resin is precipitatedand rnay be collected.washed

and dried. The complexity of these convolvulaceousresins has prevented,until lecentlv,their isolationin a pure form and they havebeen studiedby investigatingthe productsof their hydrolysis (short-chain volatile fatty acids, hydroxy fatty acids and sugars).The main constituentofjalap resinis convolvulin.a substancewith some I 8 hydroxyl groups esterifiedwith valeric, tiglic and exogonic acids.Exogonic acid is 3,6-6.9-dioxidodecanoic acid. (For its stereochemicalstructure seeE. N. Lawson et ul., J. Org. Chem.,1992,57, 353). H. ,r-*r

X to' X

,ro\

X

,rH

HrC'

cH2 _. cooH

Exogonic acid

Jalap is a powerful hydragoguecatharticand was formerly extensivcly usedeitheras standardizedpowder,as JalapResinor as Jalapin. The lattel is the decolorizedether-insolubleportion ofJalap Resin. Recently.using rrodern techniques,Japaneseresearchershave carried forward the investigationof thoseconvolvulaceousspecieswhich are of relevanceto the orientalmarket.Examplesaregiven below. Brozilion Jolop Rhizome This is derivedfrom lponroeaoperculatuand constitutesa substitutefor Mexican jalap. In a seriesof papersOno and colleagues(see Chem. Pharm.Bull.,1992,111,lzl00and references citedtherein)characterized l8 operculins(ether-soluble resinglycosides).Theseresemblethe other known jalapins in that they are monomerswith similar intramolecular macrocyclicesterstructuresin the glycosidicacid moieties.However, their componentacids(n-decanoicand n-dodecanoicacids)are characteristicallydifferent from those of previouslyknown resin glycosides (isobutyric. 2-methylbutyricand tiglic acids), see 'Jalap' above. On alkalinehydroiysisa pafiicularoperculinwill give a characteristic operculinic acid alongwith rr-decanoicand n-dodecanoicacids.Operculinic acid E, fbr exarnple,is 11S-jalapinolic acid I 1-O-s-l-rhamnopyranosyl(l-->2)-B-D-glucopyranoside. The fbrmula fbr 11S-jalapinolicacid (commonto all operculinicacids)is givenbelow:

I lS-Jalapinolic acid IpomoettbcrttrtLrs. This species,the sweetpotato,is widely cultivated as a food but it has also traditional (Brazilian) medicinal uses and a number of pharmacologicalclaims have been made for it. In 1979 Kawasakiet ul. repofiedthe rootsto containa rnixtureof hexa-,heptaand octa-decylferulates: Noda et al. (Chem.Pharm. Bull., 1992,40, 3163) isolatedfive new ether-solubleresin glycosidescalled simonins I-V. The arrangementof the acids in relation to the carbohydratemoietiesof the moleculeis illustratedbv simoninI. Rhamnose

,

/

Decanoate

Rhamnose -

Rhamnose -

Fucose

\ Cinnamate

Decanoate

Jalapinolate

Simonin I

Similar compounds(stolonif'erins)have been recordedin lpomoea .stolonifera(N. Noda et ctl.,Phy'tochemistrv-, t998,48, 837). The rootsof Convolt,ulusscammonia(vide supra) containether-soluble resin glycosidescalled scammoninslthey possessa glycosidic acid. e.g. scammonicacid A. and have an intramolecularmacrocyclic ester structure involving various sugars (see H. Kogetsu el a/.. P ht'tor:hentistn. 199 1. 30, 957).

@

ins, Sopon cordiooctive drugs ondothersteroids

Plant rnaterialscontainingsaponinshave long beenusedin rranv parts of the world fbr their detergentproperties.For example.in Europethe rool of Supottctriao.fficinali.;(Caryophyllaceae)and in SouthAmcrica the bark of Quillu.josaponaria(Rosaceae).Such plantscontaina hish percentageof glycosidesknown as saponins(Latin sttpo.soap)rvhich are characterizedb.v their property of ploducing a liothing aqueous solution.Thev alsohavehaemolyticproperties.and when injectedinto the blood strean. are highly toxic. The fact that a plant contains haemolyticsubstances is rrotproof that it containssaponins. andin the speciescxamimed by Wall ( 1961)only aboLrthalf of thosecontaining haemolytic substancesactually contained saponins.When taken by mouth. saponins are comparatively harmless. Sarsaparilla.tor example, is rich irr saponinsbr.rtis rvidely used in the prepariitionof nonalcoholicbeverages. Saponinshave a hi-qhmolecularweight and a high polarity and their isolationin a stateof purity presentssomedifficulties.Ofien they occur as complex mixtures r.viththe componentsdiff-eringonly slightly liom one anotherin the natureofthe sugarspl'esent.or in the structureofthe aglycone.Various chromatoglaphictechniqueshave been enploired lbr their isolation.As glycosidesthey are hydrolyseclby acids to give an aglycone(sapogenin)and various sugalsand relateduronic acids. According to thc structurcof the aglyconeor sapogerrin. two kinds of saponin are recognized the steroidal (commonly tetracyclic triterpenoids)and the pentacyclictriterpenoidtypes (seefbrrnulaebelow). Both of thesehavea -qlycosidallinkageat C-3 and havea commonbiogeneticorigin via mevalonicacidandisoprenoidunits

ut:itu:iuti

cHl au

(?6)

( 2 7) S t e r o i ds k e l e t o n

Pcntacyclictriterpenoidskeleton

A distinct subgroupof the steroidalsaponinsis that of the steroidal alkaloidswhich characterizemany membersof the Solanaceae. They possessa hetelocyclicnitrogen-containingring. eiviug the compounds basicproperties(asan exampleseesolasodine. Fig. 2,1.-5).

STEROIDAT SAPONINS

STEROIDAT SAPONINS 289 PENTACYCTIC TRITERPENOID SAPONINS 297 DRUGS 3O4 CARDIOACTIVE CARDENOTIDES306 BUFADIENOTIDES 312 OTHERSTEROIDS3I3

The steroidal saponinsar"eless widely distribLrtedin nature than the pentacyclictriterpenoidtype. Phytochemicalsurveyshave showntheir presence in many monocotyledonousfaniilies. particularly the (e.g.Dioscoretrspp.).Agavaceae(e.g.Agale and YrLt:c'tt Dioscoreaceae (Sntilcrxspp.).In the dicotyledonsthe occurspp.) and Srnilacaceae renceof diosgeninin fenugreek(Leguminosae)and of steroidalalkal(Solanaceae) oids in ,Sofurnuni is of potentialimportance.Somespecies of StroplttuthusandDigitulis containboth steroidalsaponinsand car'diac glycosides (q.v.). Examples of saponinsand their"constitlrent sugarsaregiven in Table24.1. Steroidalsaponinsare of great pharmaceuticalimportancebecause of theirrelationship to compoundssuchasthe sexhormones, cortisone. diuretic steroids.vitamin D and the cardiac-elycosides. Someare used as startingmaterialsfbr the synthesisof thesecompounds.Diosgeninis the principal sapogeninusedby industrybut most yams,from which it is isolated,containa mixture of sapogeninsin the glycosidic form.

A LR I G I N DD R U GO S FB I O L O G I C O AIN PHARMACOPOE AD LR E L A T E shown that such open-chain saponins are, like the more colnmon ones. fornred liom cholesterol. ln Dioscoreo homogenates one such cotnpottncl

Toble24.1 Exomplesof steroidol soponins. Occurrence

Steroidal soponin

Sugorcomponents

Sorsoponin (Porillin) Digilonin

3 glucose,I rhomnose Smi/oxspp.

has been convcrted to dioscin (a ciios-tcnin-ulycoside)(Fig. 2.1.3).

FORTHEPRODUCTION OF NATURATSTEROIDS PHARMACEUTICATS

2 glucose,2 goloctose, Seedsof Digitolis purpureoond D. 1 xylose lonoto 1 glucose,2 goloctose, Seedsond leovesof D. purpureoond 1 xylose seedsof D. lonoto spp. I glucose,2 rhomnose Dioscoreo

of somcmedicinalstefoidsis entplol'ctlconAlthoughlotal synthesis mcrcially.thereis alsoa gleatdernandfbr naturalploductsu'hichri'ill svrrthesis. serveas staltingmateriirlsfol their'Trartra/ Gitonin which illustratesthe rartgeof stercrids As indicatcclin Fi-e.2'1.-1. are I I-oxosteroids. and its clel'ivatives requireclmedicinally.co1'tisone iLndthc thc oral contraceptives" hormones. includin-t u'heleas the sex Dioscin diureticsteroidshave no oxygensnbstitutionin the C-r'ing.Fig.2:1.5 u'hichareavailnaturalclerivatires slrrlwssomeof the nroreirnpot'tant able irr sulficientquantitl'lbr syntheticpurposes.Hecogeninu'ith Cof the ntoleculeis of the stereochemistry As * ith cardiacglycosides. sor.neimportance,iilthoughnot so much so fbr cortisonemanufacture. ring substitutionplrx'ides ir practicalstarlingmateriallbr thc synthesis is suitablcfbt' thc rnarrufacn'hcrcascliosgenin Natr,rlalsapogeninsdiif'eroniy in their configurationat carbonatoms3. ol'the colticosteroids. anclthe sexhormones.Diosgenin.howcvct'. 5 and 25. and in the spirostaneseriesthe orientationat C-22 neednot be tureof olal contraccptives at a synthesisby thc cr-nplovment. (cf. steroidalalkaloicls). Mixturesof the C-25 epimers tor' can alsobc useclfbl corticosteroid specil'ied and llrnogertin {A5. suitablestagcin the synthesis.of a microbiologicalfcrmentationto example. diosgenin 1A5.25cr-spirosten-3B-ol) of thc pregnenenucleus. introduceoxygeninto the 1I o.-position 25B-spirosten-38-ol)-are of normal occurrenceand their ratio. one tn Eflbrts ale constantly being rrade to discover neu hi-eh-yielding the other, is dependentupon tactors such as morphologicalpart and by the stageof developmentof the plant. In some instancesin the planl. the strainsof plants and to assurea le-sularsupply of lau' r-ttaterial side-chainwhich forms ring F of the sapogeninis kept open by glyco- cultivation of good-clualityplants. Hardman in a revieu' on steroicls (Pltmta Med.. 1981, 53, 233) rccordedthat. annually.the American raponin salsaparilloside of side tbrnrationas in the bisdesnrosidie CherttitulAltstr.rdl,rcontainedsonte3000 rcf'cleucespel'tinentto plant Stnil ax ctri stoIocJtia efbIiu. exaurples of stcroidsor relatedcompounds.Someof the better-knovn'n and their sourccsare given in Table2'1.2.(For a steroidalsapo-uenins SAPONINS BIOGENESIS OF STEROIDAL revien'. tabulating over 200 sapogenins,see A. V. Ptttel et ttl.. rap iu. I 987,58, 67.) Steroidalsaponinsarise r,'iathe mcvalonic acid path*'ay: the prelim- F-itote fbr the subhave beendiscussedin Chapter'19.A scher-ne inary stii,ees seqLrentcyclization of squaieneto give cholesterolis illustlated irr Dioscoreq species in plantshasonly Tubcrsof rrranyofthe dioscoreas(varns)have lortgbeenusedibl tbod. the wide distributionof r.vhich Fig.2,1.1. Cholesterol. into a nutnberof relatively recently been shown, can be incorpc'rrtted ai they are rich in starch.In additionto stal'ch.somespecicscontain C17sapogeninswithorlt side-chaincleiivagc(Fig. 2'1.2).althoughit is steroidal saponins.others alkaloids. Ft'ot-ua suitable soul'ccthe not necessarilyan obligatory plecLrrsor.Extensire inrestigations sapogeninsareisolatedb1'acid hi,'dlolysisol the saponin.Previousf'erinvolving whole plants,homogenatesand cell cttltuleshave bccn per- mentationof the nraterialfbr sone ,1-| 0 days0f tcn givesa betteryield. fbrmed to elucidatethesedetailedpathways,includingthe oligin of the The water-insolublesapogcninis therrextractcdu'ith a suitableor-lanic (e.g.diosgeninandyamogenin). Cultivation reclttircs 25-epimers solvent.Both wild and cultivatedplants iuc r-rscd. As early as 1947 Marker and Lopez had postulatedthlt steroidal attentionto cori'ectsoil and drninage.sLlpporttbr the r.incs anclfleeclom saponinsexistirrplantsin a fblnr wherethe side-chainis heldopenby gly- tiom weecls,r,irus,fungusand insectattack.Accordingto the species. cosidefbnrration.However.directevidencefbr the naturaloccurrenceof the tubersreachmatulity in 3 -5yeals and on tvera-[c.yield l-13%of thesecompoundswas not forthcorningtbr another20 years.It has been totalsapogenin.

Squalene

Fig.24.r of Possible routefor theformotion in higherplontsond cholesterol olgoe.

Cholesterol

Squalenc-2,3-oxide

Zymosterol

Cycloartenol

Lanosterol

SAPONINS C,A R D I O A C T IDVREU GA SN D O T H E S RT E R O I D S @

Diosgenin

Kryptogenin

Lycqusicun

Cholesterol So/nnn

Tomatidine

tig,24.2 Someplontmetobolites of cholesterol.

Solanidine

Until 1970 diosgeninisolatedfi'om the Mexican yam was the sole sourceti)r steroidalcontraceptivemanufacture.With the nationalization of the Mexican industry,hor.l'erer.prices were rnereasedto such an extentthat manllfactlllersswitchedto hecogeninfor corticosteroids, to other sourcesof diosgeninand to the use of the steroidalalkaloidsof Solortumspecies.Totiil syrrthesis alsobecameeconomicalll,feasibleand

loble 24.2

is now much used.Nlorerecently.the econonrie.ol':teroidprocluction have again changedin that China is nos c'rporlinu Iurgcquirntitiesof diosgeninlit is of high quality.beingliee o1'thcl5$i., 'nrerr rnrtrgenin. althoughthis is of no commercialsignificance.end i\ f!-a\onahllpriced. Threeof the manyDioscoreaspp.founclin (hina antl u:etl contntercially aregiven in Ttrble24.2;the tubersof thr-st-r icld I i i of diosgenin,with

Some sleroidol sopogenins ond their sources.

Sapogenin

Species

Locotion

D i o s g e ni n

Dioscoreosylvotico D. mexiconoond D. composifo D. collettii,D. pothoicoond D. nipponico D. floribundo D. deltoideo ond D. prozert D. tokoro

Tronsvool ond Notol Mexicoond CentrolAmerico Lnrno Guotemolo ond cultivoted in lndio lndio Jopon lndio TropicolAmerico;inkoducedintoWestBrozil NorthAmerico Indio,Egypt,Morocco Subtropicol Americoond cultivoted in Kenyofor s i s ool n d s o p o n i n Mexico CentrolAmerico CenholAmerico Africo

(-ncLr
Cocaine,etc. , n

Ecgonine OH OH

+-'i.lCalystegine A3

>-

HOHpC

d

Fi1.27,2 S o m e o r n i t h i n e - d e r i v e do l k o l o i d s .

|

t*--Necine

----------- senecio alkaloids

ALKALOIDS Me

BIOGENESIS OF TROPANEAIKALOIDS

Nr)---l

As the charactelisticalkaloidsofthe groupareestersofhydroxytropanes and variolrsacids(tropic.tiglic. etc.)thereare.tbr cachalkaloid.two distinct biogeneticmoietieswhich warrantconsideration.Most studiesin Ph oco this connectit'rrr hal'e r-rtilizecl various speciest'f Datura because,fcrra numbero1'reasons. they ar"eoneof the mostcorl'enientof the Solanaceae I cHzoH cH2oH with rvhich to work. However.with the adventof isolatedroot culture technique s the stuclyol alkaloid fbnration in other generahas become Hyoscyamine, Alropine H y o s c i n e{ S c o p o l a m i n e } more eviclentand Japanese vn'orkers in particulalhavecmployedspecies of Hlo.r'rrzzrrrr.r ind Duboisiuwith considerable success. 'l'ropane enzymatic hydrolysis but the chemical treatment convefts it to thc moiety. The availableevidencesuggeststhat the forrnamore stablegeometricisomer.oscine). tiorr of the tropancring svstemis generallysimilar for all Solanaceae These thlee specitic alkaloids are confined to the Solanaceae.in studiedbr-rttherealc still apparentI'ariationsbetwecnspecies.farticuwhich sonre,10difl'erentesterbasesof the tropanet-vpchavenow beerr larly in the steleospecificincolpolationof sonreprecursors. discovered;they constitutean interestingchemotaxonomicstudyrvithin Early work with isotopcsindicatedthat ornithine and acetatewere the fanrily.Exarrplesof tropanolestersare-eivenin Table27.2.Dimeric precursolsof the troparrerruclcr-tsl later'.the incorporationof ornithine and trirneric tropanol ester alkaloids involving the dicarboxylic was shownto be stereospecific. H1'glinccan alsoserveasa prccursorof acidsmesaconicand ittrconicacidsiile tor.rndin Schi:.anthLrs. For recent the tropancring but is not novuconsiclered to lie on the principalpathisofationsfrorri S. ltorrigens see O. Muiioz and S. Cort6s. Phunn. way. The N-rnethyl group of the tropanesystemcan be suppliedby Biol.. 1998,36. 162.Other tropanebasesoccur in the Erythroxylaceae methionineanclcan be incorporatecl at a very early stageof biosynthe(see cocaine in coca leaves). Convolvulaceae.Dioscoreaceae. sis. as demonstratedby the intact incorporationof ly'-nethylornithine Rhizophoraceae. Crucif-erae and Euphorbiaceae. into hyoscineand hyoscyamineof l)utlo'tt trtetel .:.ndD. strunoritutt. Early involvementof thc N-methyl group was reinfbrcedby the isolation in l98l of natulall-voccurring6-N-nethl"lolnithinefrorn bellaclon*.CHs nl plants. Also supportingthe stereospeciticityof the olnithine ,cH, Hot /l incorporationu,asthe work of McGaw and Woolley (.Phvochenistry, | 982. 21. 26-53) which shou'edthat fbl D. neteloitleslhe C-2 of hygrine was specificallyincorporatedinto the C-3 of the tropine moiety of the tl isolatedalkaloid. Putrescine(the symmetricaldian.rinefbrmed b1' the o ^.\ \-H decarboxylationof ornithine)and its N-n'rethyldclivative also serveas l l precursols,u'hich.takenin conjunctionwith the stereospecific incorporation of ornithine.makesit difTicultto constrlrcta singlepathway for i l l tropancrin-t formatii'rn.Arrotherproblern involved the fbnnation of a o cHc derivative of hvgrine by the condensationreaction between the Nrnethyl-A1-pyrroliniumion and an trcetate-derived precursor.Fol recent Schizanthine Z- a tropandiol mesaconic aciddiester work on this aspectseeR. Duran-Patl'on(,/ ul., Pltytot'henrisar'. 2000. 53.117.A schemefbr thc biogenesis of the tropanentoiery.consistent Altogethelover 200 tropanealkaloidshave now been recorded. u'ith the abovefindings.is shor.vnin Fig. 27.3. (Buscopan). Semisl'nthetic delivatives. e.g.hyoscinebLrtylbrornide are Studieson the enzymc putrescineN-rrethyltransf'elase in cultr.u'ed of medicinalirnportance. loots of llr'osct untu.s ulbus sLrpportthe rolc of this enzynreas the f irst

r-> /

\

\

Y

? " ntc-l\y">l\

x Z \ \i

\

d

o>r\-\o

lable 27.2

Exomples of ester components of tropone olkoloids of the Solqnoceoe.

G e n e r o o f p h o r m o c e u t i c o li n t e r e s l

Atropo,Acnistus, Scopolio,Physochloino, Przewolskio, Hyoscyomus, Physolis, Mandragoro,Doturo, Solondro.Duboisio.Anthocercis

T r o p o n o l c o m p o n e n l so f e s t e r s

N-R'

N-CH

OH

OH Rl=HorCH: R2=HorOH R3=HorOH (Tropine:Rl = CHr, R2=R3=H) Esterifying ocids

*.tF!h^..,.

Scopine:Rl = CHr Norscopine: Rt = H (Esterifiedwith tropic or atropicacid only)

H q-Tropine (Esterifiedwith tiglic acidonly)

Acetic,propionic,isobutyric, isovoleric, 2-methylbutyric, tiglic,nononoic,tropic,otropic,2-hydroxy3-phenylpropionic, 2,3-dihydroxy-2-phenylproponoic, p- methoxyphenylocetic, onisic

@

P H A R M A C O P O E IA N L D R E L A T EDDR U G SO F B I O L O G I C AOL R I G I N

onic acid(phenyllacticacid)of thc tropanealkaloidlittorine.The specitic incorporationsobtainedwith phenylalanineare given in Fi-1. of the side-chainin involvedin the rearrangement 21.4.The sequencc the conversionofphenylalanineto tropic acidhas beenthe subjectot' longstanding debate. Rccently. Ansarin and Wooller (Pht'rothentisrn'.199,1.35. 935). by f'eedingphenyl f l.-jlrC2llaetie acid to D. struntoniuntanelexnnriningthe llC-NMR spectraof thrsubsequently isolatedhyoscineand hyoscyarrine.have substantiatecl the hypothesisthat tlopic acid is formed by an intramolecular Furthcrmore.it hasbeendernonstratrearangementof phenyllactate. fiorr littorine by a process ed that hyoscyamineis biosynthesized involving the intramolecularrearan-eementof the phcnyllactatemoiety of the alkaloid(R. J. Robinsat ul.,J. Chem.Sot. PerkinTruts l. : . A n s a r i na n d J . G . W o o l l e y .J . C h e m .S o c . 1 9 9 4 .6 1 5 : 1 9 9 5 . ' 1 8 1M Perk. Trutts1. I 995. 487). I n concordancewith this. transformedroots u'ill convert exogenouslyadded littorine to of Daturu strtu'rtonit.urt hyoscyamine(357crnetabolismrecolded)but, in contrast,exogcltis not rnetabolized to littorine(I. Zabetakis oLrslyaddcdhyoscyanrine et al., Pltutt Cell.Rep.,1998,18, 3,11).The abovepathwayhast'ecentworkers (R. Duran-Palron et al.. Esterification. The next stagein the biosynthcsisofhyoscyamine,the ly been confilmed by other l1 1 Phrtochen i stn, 2000. 53. ). by esterilicationof tropine and tropic acid. has been demonstrated lsoleucineservesas a precursorof the tigloyl and 2-methylbutanoyl feeding experimentsand isoiatedenzyntes.It was over 35 years ago moieties of varior.rsrrono- and di-estersof the hydroxytropanes. of a hyoscyrmineesterase thatKaqzkowskifirst recoldedthe presence more recentlyRobins at al. (.FEBSLett.. 1991,292, Biogenesisof hyoscine(scopolamine). Wolk initiatcd by Romeikein in D. stramctnirrT?; 293) demonstratedthe involvernent of two acetyl-CoA-dependent 1962 showedthat hyoscineappealedto be fbnned in the leavesof D. acyltransferasesin the respective forn'ration of 39.-and 3B-ace- .feror frorn hyoscyaminevia 6-hydrox,vhyoscyamine and 6.7-dehydroroot cultures. toxytropanesin D. .stramortii,rt-transfoLmed as hyoscyamine.The fbrmer intermediatehas been well substantiated, Acid moiety. The tropic acid iiagrnent of hyoscineand hyoscyamine indicatedbelow,and occursin quantityin someother genera(Scopoliu. Przev'ttlskia)but the latter, although incorporatedinto is derived from phenylalanine,as is the u-hydroxy-B-phenylpropi- Phl'soc'hluina.

committed enzyme specific to the biosynthesisof tropanealkaloids. (N. Hibi er al.. Plant Physiol.,1992,100. 826.) It will be observedfrom Fig. 27.3thatthe reductionof tropinoneyielcls both tropine (3c-hydroxytropane)and pscuclotropine(38-hydroxl'tropane). These reductions are brought about by two independent (EC 1.I . I .236),oftenref'erredto asTR-l andTR-l I. tropinonereductases researchinvolrwhich acceptNADPH ascoenzyme.Alter considerable ing principally D. .strunoniumroot culturesboth enzynreshave nor.vbeen (A. Portstefl-en et ol., Plntotltern., separatelypurilied and characterized 1994,37,391). Furtherrnorc.cDNA clorrescoding fbr the two sepai'ate enzymesTR-l and TR-II have been isolatcd and shown to involve polypeptides containing 212 and 260 amino acids respectively (K. Nakajimaet al.. Pntc. Natl Acud. Scl. USA. 1993.90. 9591).These clones were expressedin Escherit:hiut'oli anclthe samereductive specificity demonstratedasfor the naturalTRs isolatedfiom plant rnaterial. alkaloids.hydroxyls and As indicatedin Table 27.2 for solanaceous estergroupsarealsocommonat C-6 andC-7 (Rl anclR3) of the tropane ring system.Cunent evidencesuggeststhat hydloxylationof thesecarbonsprobablyoccursafterthe C-3 hydroxyl hasbeenestelified.

cooH

cooH

D*t, \

l\4ethylation D*n, \

Decarboxylation NHCH3

NHCH3

NHz

N-methylputrescine

6-N-methylornithine

Ornithine

I I

oxioation

I /

COSCoA

\

f-\

z

.-

x

Acetyt-coA

|,-CHz/ N - C H 3 / C : O NHCH3

N-Methyl-A'-pyrrolinium sall

Fig.27.3 P o s s i b l eb i o g e n e t i cr o u l e sf o r t r o p i n e o n d p s e u d o t r o p i n e( s e et e x t f o r o d d i t i o n o lc o m m e n t s ) .

Eo Tropinone

Reduction F.-)

"t

Tropine(and'li-tropine)

4-Methylaminobutanal

ALKALOIDS

Doturo stromonium

i l l Y + l H O H,C-"'C-H

P h e n y l a l a nn ie

I .cooH

'CH, II H-C-OH

I

.cooH o - H y d r o x y - p - p h e n y l p r o p i o n i ca c i d

Tropic acid

Fig.27.4 Demonstroted incorporotions of phenylolonine intothetropicocidondcr-hydroxy-B-phenylpropionic ocid(phenylloctic ocid)moieties of hyoscyomine o n d l i t t o r i n e ,r e s p e c t i v e l yF. o r m o r e r e c e n tw o r k c o n c e r n i n gt h e i n l o c t i n c o r p o r o t i o no f ( R ) - ( + ) - 3 - p h e n y l l o cot icci d i n t o t h e h o p o y l m o i e f i e so f t r o p o n e o l k o l o i d s s e e r e f e r e n c e si n t e x t .

hyoscinewhen fed asa precursorb D. ferox,has neverbeenisoiatedfrom normal plants. Some 25 years later Hashimoto's group, using Hyoscyamus niger cultured roots, isolated and pafiially purified the enzyme responsiblefor the conversion of hyoscyamine to 6-hydroxyhyoscyamine.They used this enzyme to prepare 1$-taOl-hydroxyhyoscyamine from hyoscyamine and showed that when the labelled compound, fedto Duboisia myoporoides,was convefied to hyoscinethe l80 was retained, thus eliminating 6,7-dehydrohyoscyaminefiom the pathway (Fig. 27.5). For this reaction to proceedthe epoxidaseenzyme requires2-oxo-glutarate,fenous ions and ascorbateascofactors,together with molecular oxygen (fbr full details see T. Hashimoto et al., Plant Physiol., I 987, 84, 144;Phyrochernisrry,1989,28, 1077). The elucidation of the above pathway, which has spannedmany years,aptly illustratesthe value of biotechnologyand enzymologyin contributingto the resolutionof someuncertaintiesresultingfrom traditionallabelled-precursor experiments. Ontogenesis. In some plants of the Solanaceae(e.g. belladonnaand scopolia) hyoscyamineis the dominant alkaloid throughout the life cycle of the plant. In D. stramoniumhyoscyamineis the principal alkaloid at the time of flowering and after, whereas young plants contain principally hyoscine;in many other speciesof Datura (e.g. D. ferox)

H rbt-c.-:

Hr?-B.-i |

I

,N-M" i

l-lrc-fi-i

i

,N-M"i

HOC-C-: H H

i

6-Hydroxyhyoscyamine

Hyoscyamine

_-/ ->s

I

hyoscineis the principalalkaloid of the leavesat all times.The relative proportionsof hyoscine and hyoscyaminein a particular speciesnot only vary with ageof the plant,but alsoare susceptibleto other factors, including day length, light intensity. general climatic conditions, chemical sprays,hormones,debudding and chemical races. Isolated organ cultures of belladonna,stramonium and hyoscyamusindicate that the root is the principal site of alkaloid synthesis;however, secondary modifications of the alkaloids may occur in the aerial parts, lbr example,the epoxidationof hyoscyamineto give hyoscine. and the formation of meteloidinefrom the corresponding3,6-ditigloyl ester.

Further reoding Griffin W J, Lin G D 2000 Chemotaxonomy and geographical distribution of tropane alkaloids. Phytochemistry 53: 623-637 LounasmaaM, TamminenT, 1993Tropanealkaloids.In: Cordell G A (ed) The alkaloids. Chemistry and pharmacology.Vo1zl4.Academic Press,London. A review with 184 referenceslisting all known tropane alkaloids. Robins R J, Walton N J 1993The biosynthesisof tropanealkaloids.In: The alkaloids. Chemistry and pharmacology.A review with 191 reJerences. Woolley J G 1983Tropanealkaloids.In: WatermanP G (ed) Methods in plant biochemistry.Vol 8. Academic Press,London,p 133

STRAMONIUMLEAF Stramonium Leaf BP (Thornapple Leaves: Jimson or Jamestown Weefl consistsof the dried leavesor dried leavesand flowering tops of Datura stramoniumand its varieties(Solanaceae). The drug is required to containnot less than025% of alkaloidscalculatedas hyoscyamine. The plant is widespreadin both the Old and New Worlds. British supplies are derived mainly from the Continent (Germany, France, Hungary,etc.).

Plant. D. Stramoniumis a bushy annualattaininga height of about 1.5 m and having a whitish root and numerousrootlets.The erectaerii H H al stem shows dichasial branching with leaf adnation. The stem and Feedngof c-c-! branchesareround, smoothand green.The flowers (Fig. 27.6) aresoliPrecuraor tary, axillary and short-stalked.They have a sweet scent.Each has a HC-C-l tubular,five-toothedcalyx about 4.5 cm long, a white, funnel-shaped H H i H i corolla about 8 cm long, five stamensand a bicarpellaryovary. The 6,7-Dehydrohyoscyardne Hyoscine plant flowers in the summerand early autumn.The fruit is originally Fig.27.5 bilocular but as it maturesa false septumarises,exceptnear the apex, Route forfheformotion (portiol of hyoscine fromhyoscyomine lormuloe] so that the maturefruit is almostcompletelyfour-celled.The ripe fruit

Hc_g_i

ll)'-*i

I

dl 'N-u"i t-c'-l

@

AL RIGIN S FB I O L O G I CO P H A R M A C O P O EAIN AD L R T I A T EDDR U G O

Fig.27,6 (theorrow B,corollo cutopenC, pistil(therestof theflowerhosbeencutowoy);D,floroldiogrom shoot; A, Endof flowering DJturo stromonium. i n d i c o t e st h e p l o n e o f s y m m e t r y ) ;E , c o p s u l eo p e n i n g ; F , c o p s u l e i n t r o n s v e r s es e c t i o n ;G , s e e d i n t r o n s v e r s es e c t i o n ,s h o w i n g c u r v e d e m b r y o . A l l s l i g h t l yr e d u c e d e x c e p t G , w h i c h i s e n l o r g e d . ( F r o mR e n d l e ' sC l o s s i f t c a f i o no f F l o w e r i n g P l o n t s . )

seeds(Fig. 27.6G) is a thornycapsuleabout3 z1crn long.Stt'amonium in or-rtline and about 3 reniform blackish in colour. are dark brown or mm long. The testais reticulatedand finely pitted.A coiled embryo is embeddedin an oily endospernr. var.tatula closely resemblesthe abo\e: it\ stenlsxre D. stram.oniurn reddishand the leaveshave purplish veins. as also have the lavender'colouredcoroilas.Varietiesof both the abovetblms occur with spinelesscapsules.

tened.longitudinallywrinkled. somewhathairy and vary in colour fronr light olive brown (D. stamoniurl) to purplish-brown(var. tut' a/a). Stramoniumhas a slight but unpleasantodour, and a bitter taste.

Microscopical characters. A transversesectionof a leaf (Fig. 27.7t showsthat it has a bitacial sffucture.Both surlacesare coveredwith a smoothcuticle and possessboth stomataand hairs.Cluster crystalsol' calcium oxalate are abundantin the mesophyll (Fig. 27.7F, G), and the microsphcnoidaland prismaticcrystalsare alsofound. The stomataarLhy to*'alds grown in England Gerarde was History. Stramonium end of the sixteenthcenturyfiom seedsobtainedfiom Conslantinople. of the anisocyticand anomocytictypes.The epidermalcells havewar'1 The genericnarne.Datura. is derivedfront the nanteof the poison.riftrit. walls, particularlythoseof the lower epidermis.The uniseriateclothing hairs are three- to five-celled, slightly curved. and have thin. wartl which is preparcdfiom Indianspeciesand was usedby the Thugs. wal1s(Fig. 21.78). The basal cell is usually more than 50pm long Macroscopical characters. Fresh stramonittmleavesor herbarium (distinctionfrom D. rzclel). Small glandularhairs with a one- or twospecimensshould tirst be examined.since the commercialleavesare celledpediceland otherswith a two-celledpediceland an oval headof two to sevencells arealsofound. If poltions of the leaf areclearedwith much shrunkenand twisted.and their shapccan only be ascertainedby aftet'soakingthem in water. chloral hydrate solution. the abundanceof the cluster crystals ot carefuln-ranipulation The dlied leaves are greyish-greenin colour. thin, brittle. twisted calcium oxalateand their distt'ibutionwith regardto the veins may be and ofien broken.Whole leaves(Fig. 27.6) are 8-25 cm long and 7-I-5 noted. The midrib showsa bicollateralstluctureand characteristicsubepicm widel they are shortly petiolate.o\rateor triangular-ovatein shape. nlargin.They are dermal mzrsses of collenchymaon both surfaces.The xylem forms a ale acuminateat the apex and have a sinuate-dentate stronglycurvedarc. Sclerenchymais absent. distinguishedfrom the leaves of the Indian species.D. innctxia.D. teeth dividing Stemsare present,but few of theseshould exceed5 mm diameter. metel and D. .fustuostt.by the margin. u'hich possesses They possessepiderrnal hairs up to 800 pm long and have perithe sinuses.and by the lateralveins which run into the marginalteeth. The commercialdrug containsoccasionalflowers and young cap- medullary phloern. The stem parenchymacontains calcium oxalate sules. which have been desclibed above. The stems al'e ofien f-lat- sirnilarto that fbund in the leaf.

ALKALOIDS UEP

-,\,

c J

.j;,: i

. \

J.i^" '"-J

':if:!*

Fig.27.7 Doturostromonium leof.A, Tronsverse sections of midrib(x15);B, tronsverse sectionportionof lomino;C, lowerepidermis with stomotoond glondulortrichome; D, glondulorhichomeovervein;E,clothinghichomes{ollx200}; F,orrongement of colciumoxololecrystols in crystolloyer, surfoceview (x50);G, colciumoxolotecrystols in cells;H, upperepidermis showingcicotrixond stomoto(G ond H, x20O).l, J, Sconning electron microgrophs of {l)clothingtrichome ond (J)glondulortrichome. c, Collenchymo; cic,cicotrix;c.l, crystolloyer;e, endodermis; id, idioblostcontoining micro-crystols; i.ph,introxylory phloem;l.ep,lowerepidermis with stomo;m, mesophyll; ox, colciumoxolotecrystol;p, polisodeloyer;ph, pntoem; u.ep,upperepidermis with stomo;vt, veinlel;xy, xylem.(Phologrophs: L.Seedond R.Worsley.) Constituents. Stramoniumusually contains0.2-0.45c/cof alkaloids. the chief of r."'hichare hyoscyamineand hyoscine,but a little atropine may be formed from the hyoscyarr-rine by racemization.At the time of collectionthesealkaloidsare usually presentin the ploportionof about two pafis of hyoscyamineto one part of hyoscine,but in young plants hyoscineis the predominantalkaloid.The TLC testfor identitygiven in the BP enablesolher Datura speciescontaining diff'erentproportions of alkaloidsto be detected.The largerstemscontainlittle alkaloid and the official drug should contain not more Iha'n37a stem with a diameter exceeding 5 mm. Stramonium seedscontain about O.2Vr:of mydriatic alkaloids and about | 5-307c of tixed oil. The roots contain.in addition to hyoscineandhyoscyamine,ditigloyl estersof 3.6-dihydroxytropane and 3,6.7{rihydroxytropane. respectively,and a higher propofiion of alkamines than the aerial portions. D. stramonituttcell and root cultureshave been considerablyutitized in biogeneticstudies(seeabove and M. G. Hilton and M. J. C. Rhodes.Plunta Med., 1993.59, 340).

thn

PreparedStranton.iunt BP is the finely powdereddrug adjustedto an alkaloidcontentof 0.23-0.21Vo. Alfied species. All Dlturo speciesexaminedto date contain those alkaloids fbund in stramonium.but fi'equentlyhyoscine.rather than hyoscyamine,is the principal alkaloid. A number of alkaloids not reported in D. stramoniunt have also been isolated from vadous species:these include apohyoscine.norhyoscine,norhyoscyamine. tigloidine. 3a-tigloyloxytropane,3o-acetoxytropane.hetero diesters of di- and trihydroxytropane,meteloidineand cuscohygrine. ' Commercial 'daturaleaf consistsof the dried leavesand flowering tops of D. innoxia and D. ntetel:it is obtainedprincipally from India. Like thoseof stramonium.the dried leavesare curled and twisted.but :Lreusually sonrewhatbrowner in colour.with entiremarginsand with difTerences in venationand trichomes.The leavescontain about 0.57c of alkaloids.Variationsin hvoscineand atropinecontentsin different

E

ORIGIN AND RELATED DRUGSOF BIOLOGICAL PHARMACOPOEIAT organs of D. metel during development have been studied (S. Af.sharypuoret trL..Plttnta Med.. 1995,61, 383). Over 30 alkaloids have beencharacterizedfiom D. inno.ria by capillary GLC-mass spectrometry.For studieson the anatomyof the leaf of D. meteL,seeY. C. Anozie, Int. J. Crude Drug Res.,1986,24,206;and for the isolationof see S. Siddiqut et al., J. Nat Prod., 1986,49, 3cx-anisoyloxytropane 'Datura seeds' are derived from D. metel and possibly other 511. species.Each seedis light brown in colour and ear-shaped.They are largerand more flattenedthan stramoniumseedsbut resemblethe latter in internal structure.The alkaloid content,hyoscinewith tracesof hyoscyamineand atropine,is about O.2Vc.D..feror, a specieshaving very large spines on its capsules,contains as its major alkaloids hyoscineand meteloidine. 'ffee-daturas'constituteSectionBrugmansiaof the genus;these The alboraceous,perennialspeciesare indigenousto South America and are widely cultivated as ornamentals.They produce large, white or coloured trumpet-shapedflowers and pendantunarmedfruits. Some speciesconstitutea potentialsourceof hyoscine(W. C. Evans,Pharm. in particular,hasproveda most J).,1990,244,651)andD. sanguinea, interestingplant with respectto its wide rangeof tropanealkaloidsand has been cultivated commercially in Ecuador.lt yields about 0.8% hyoscine. Plantationshave an economically useful lif'e of about l0 years. Chemical races of D. sanguineaare evident. particularly one producing relatively large amounts of 6B-acetoxy-34-tigloyloxytropane. Various tree datura hybrids developed at Nottingham University.UK, have been used by a number of workers for alkaloid studiesinvolving hairy root and root cultures; as an example see P. et al., Plant CeLlRep.,1998,17,405. Nussbaumer The South American Indianshave long cultivated various racesof theseplants for medicinal and psychotropicuse (for a comparisonof of their potencywith alkaloid content,seeBristol er native assessment al ., Lkt ,-dia, 1969, 32, 123). Withanolides (q.v.) are also found in some speciesof the genus.(For the fbnnulae of I 1 compoundsof the daturametelintype seeK. Shingu er ttl., Chem.Pharm.Bull., 1990,38. 2866.)Recentreportsfeaturetheisolation of a new pentahydroxywithanolidefrom D. fastuosa (M. Manickam et al., Phl'tctcherr.,1998, 47, 1421)and the 7-hydroxywithanolidesfrom D. ferox (A. S. Veleiro et al., J. Nat. Prod., 1999,62, 1010). A classicalwork of referenceon the geneticsof the genusis that of Averyet al., Blakeslee.The GenusDatura (1959);this was updatedby anotherpublication(No. I 2 in a seriesof Monographsin Developmental Biology) and had a wider scope:Conklin, Geneticsand BiochemicaLAspectsof the Developmentof Datura(1976).

Uses. Atropine has a stimulantaction on the centralnervouss\ \telr: and depressesthe nerve endings to the secretoryglands and plaLr: muscle. Hyoscine lacks the central stimulant action of atropine: rtsedativeproperliesenableit to be usedin the control of motion sick' ness.Hyoscinehydrobromideis employedin preoperativemedication. usually with papaveretum,some 30-60 min before the induction Atropine and hyoscine are used to a large extent in of anaesthesia. ophthalmicpracticeto dilate the pupil of the eye.

HYOSCYAMUSLEAF HyoscyamusLeaf (Henbane)consistsof the dried leavesot the dned leaves and flowering tops of Hyoscyatnusnlger (Solanaceae).It i. requiredto containnot lessthan 0.057cof total alkaloidscalculatedat hyoscyamine.The EP (BP) descriptionrefersto petiolateaswell as sessile leaves,the first-yearbiennialleavesbeing thus admitted.Henbane is no longercultivatedcommerciallyin Britain and suppliesareimported from central Europe. The plant is also cultivated in the USA.

Plant. Henbaneis a biennial(.var.a-biennis)or annual(var.B-anruutt plant.It is found wild, chiefly nearold buildings.both in the UK and in the restof Europe,and is widely cultivated.Beforeexaminingcommercial henbaneleavesit is advisableto studygrowing plantsor herbariunt specimens.The differencestabulatedin Table27.3 shouldbe noted. HenbaneJknver.shave the formula K(5), C(5), 45, G(2). The hair1. five-lobed calyx is persistent.The fruit is a small, two-celled pyxis (Fig. 42.68), which containsnumerousseeds. Henbaneseedsaredark grey in colour, somewhatreniform in shape and about 1.5mm long. They have a minutely reticulatedtestaand an internal structure closely resembling that of stramonium seeds. Henbaneseedscontain about 0.06-0.i07o of alkaloids (hvoscvamine with a little hyoscineand atropine). History. Henbane,probablythe ContinentalH. albus, was known ttr Dioskurides and was used by the ancients.Henbane was used in Englandduring the Middle Ages.After a period of disusein the eighteenth century the drug was restored tothe London Pharmacopoeia of 1809,Iargelyowing to the work of Stcjrck.

Collection and preparation. Biennial henbanewas the variety traditionally grown in England,but much of the imported drug is now of the annual variety or is derived from the allied speciesH. albus.The germination of henbaneseedsis slow and often erratic and may often be assistedby specialtreatments(e.g.concentratedsulphuricacid,gibberellic acid or splitting of the testa).The plant may be attackedby the Adulterants cited are the leaves of species of Adulteration. potato beetle, and spraying with denis or pyrethrum may be necessary. Xanthium (Compositae),Carthamus (Compositae)and Chenopoditrm The annualplant usually flowers in July or August and the biennial (Chenopodiaceae). which are, however,easily distinguishedfrom the in May or June.The leavesshouldbe dried rapidly,preferablyby artigenuinedrug. ficiai heat at a temDeratureof about 40-50"C.

Table 27.3

Comporison of commerciol vorieties of hyoscyomus.

First-yearbienniol

Second-yearbiennial

Annual

Stemvery short Leovesin o rosetteneorthe ground. Ovote-lonceolote ond petiolote, up to 30 cm long,thelomino beingup to 25 cm long.Hoiry Doesnot normollyflowerin the first yeor

Stembronchedond up lo 1.5 m high to triongulor-ovote. Leovessessile,ovote-oblong lO-20 cm long.Morgindeeplydentofe in the or pinnotifid. Veryhoiry,especiolly neighbourhood of themidribond veins FlowersMqy or June.Corolloyellowishwith deep purpleveins

Stemsimpleond obout0.5 m high Smollerthonthoseof the bienniol Leoves sessile, plont,with o lessincisedmorginond fewer hoirs Flowers Julyor August.Corollopolerin colour ond lessdeeplyveined

{

ALKALOIDS Macroscopical characters, Commelcial henbane consists of the leavesand flowering tops describedabove.The leavesaremore or less broken but are characterizedby their greyish-greencolour,very broad midrib and greathairiness.If not perf-ectlydry, they are clammy to the touch, owing to the secretionproduced by the glandular hairs. The stems are mostly less than 5 mm diameter and are also very hairy. The flowers arecompressedor brokenbut their yellowish corollaswith purple veins are often seenin the drug. Henbanehas a characteristic, heavy odour and a bitter, slightly acrid taste. Microscopical characters. A transversesection of a henbaneleaf shows a bifacial structure(Fig. 27.8A). Both surfaceshave a smooth cuticle.epidermalcellswith wavy walls. stomataof both anisocyticand anomocytictypes. and a large number of hairs. which are particularly abundanton the midrib and veins. The hairs are up to 500 pm long; some are uniseriateand two to six cells long, while others have a uniseriatestalk and a large,ovoid, glandularhead,the cuticle of which is often raisedby the secretion(Fig. 27.8E).Similar hairs are found on the stems.The spongymesophyllcontainscalcium oxalate,mainly in the form of single and twin prisms,but clustersand microsphenoidal crystalsare also present(Fig. 27.8B,D). The broad midrib containsa vascularbundle, distinctly broaderthan that of stramonium,showing the usualbicollateralarrangement, which is alsoto be seenin the stems. The mesophyllof the midrib is madeup of two thin zonesof collenchy-

ma immediatelywithin the epidermi and a ground massof colourless parenchymashowing large, intercellular air spacesand containing prismsor, occasionally,microsphenoidalcrystalsof calcium oxalate. The calyx possesses trichomesand stomata,as in the leaf.The corolla is glabrous on the inner surlace but exhibits trichomes on the outer' surface,particularly over the veins (Fig. 27.8G). Those cells of the corolla which contain bluish anthocyaninsturn red with chloral hydrate solution.Numerouspollen grains are present,about 50 pm diameter, tricolpate with three wide pores and an irregularly, finely pitted exine (Fig. 27.8F).The testaof the seedshas an epidermiswith lignified and wavy anticlinalwalls, and sclereidsarepresentin the pericarp. Constituents. Henbaneleavescontain about 0.045-0.14% of alkaloids and yield about 8-727a of acid-insolubleash (BP not more than l2clc).Hyoscyamineand hyoscinearethe principal alkaloids.The petiole appearsto containmore alkaloid than the lamina or stem. PreparedHyosclantusBP ts the drug in fine powderadjustedto con'loss tain 0.05-0.077cof total alkaloids.It has a on drying' requirement of not more lhan 5.07a. Allied drugs. H1,-oscl'amus albus rs grown on the Continent.particularly in France,and in the Indian subcontinent.It has petiolate stemleaves and the flowers have pale yellow, nonveined corollas. Quantitativelyand qualitativelyits alkaloidsappearsimilar to thoseof H. niger. It hasbeenusedin biogeneticstudies(q.v.)andthe hairy roots

i--c.l t

m

31."p

$tr. &

#& D

@

Fig.27.8 Hyoscyomus niger.A, Tronsverse sectionof midribof leof (x40);B, tronsverse sectionof portionof leoflomino;C, portionof leofupperepidermis, E, trichomes; F,pollengroins;G, portionof epidermis of corollowith ottochedglondulortrichome(oll surfoceview;D, colciumoxolotecrystols; x20O).b, Boseof trichome; g.t, glondulorhichomeor portionof; id, idioblost;i.ph, c, collenchymo; cic, cicotrix;c.l, crystolloyer;e, endodermis; phloem;l.ep,lowerepidermis; m, mesophyll; p, polisodeloyer;ph, phloem;st,slomo;tr1,tr2,wholeond brokenclothingtrichomes, introxylory respectively; vl, veinlet;xy, xylem. u.epiupperepidermis;

at;h*

E

PHARMACOPOEIAL AND RELATED DRUGSOF BIOLOGICAL ORIGIN (transtbrmedwith Agrobacteriumrhizogenes)have beenanalysedfbr littorine.hyoscineandhyoscyamine 7B- and6B-hydroxyhyoscyamine. (M. Sauerweirr and K. Shimomura.Ph;'tochemistrt.1991,30.3217). ln traditionalmedicineof the Tr.rscan archipelagothe seedsarepressed into the cavities of decayedteeth to obtain pain relief (R. E. Uncini 181). ManganelliandP.E. Tornei,./.EthnopluLrmutologl',1999,65, H1'oscyamus muticus is indigenousto India and Upper Egypt; it has beenintroducedinto Algiers. For further details,seebelow. Indian henbane.Under this name considerablequantitiesof drug into Britain during World War Il. Although H. niger is were irr-rported grown in hidia and Pakistan,much of the drug came liotn a closely hyoscineand hyoscyamine relatedplant. H. reticultttus.This cor-rtains and microscopicallyit is alr-nostidenticalro H. niger. HyoscyarnusaureusandH. pusillus aretwo specieswhich produced hyoscineas the principal alkaloid.

HERB BETLADONNA BelladonnaHerb BP (.Belladutnalerfl consistsof the dried leavesand tlowering tops of Atropa belladonna (Solanaceae);it contains not less than 0.307coftotal alkaloidscalculatedashyoscyamine.Traditionally the BP drug has consistedof all the aerial parts(BelladonnaHerb) but under thereis a limit (37c)of stemwith a diameter the Eulopeanrequirements exceeding5 mm. The USP.which requires0.35%alkaloid,alsoadmitsA. rt.t:uminatt(seebelow)in the BelladonnaLeaf monograph. A. belladonn is cultivatedin Europeand the USA.

Plant. The deadly nightshade,A. belladonna, is a perennial herb which attainsa height of about 1.5 m. Owing to adnation,the leaveson the upperbranchesarein pairs,a largeleaf and a smallerone. The f'lowers appear about the beginning of June. They are solitarl'. shortlystalked,droopingandabout2.5 cm long.The corollais campanupurplish colour.The five-lobed calyx is perUses, Henbaneresemblesbelladonnaand stramoniumin action but late, five-Iobed and of a dull to the purplish-black beny. The latter is sistent, remaining attached is somewhatweaker.The higher relativeproportionof hyoscinein the conttrins numerous seedsandis aboutthe sizeof a cheny (Fig. bilocular, give rise to cerebralexcitement alkaloid mixture makesit lesslikely to plant is often known as the 'Poison Black 42.6C). In the USA the than does belladonna.lt is often used to relieve spasmo1'the urinary 'Tollkirschen'(i.e. Mad Cheny). A Cherry', while the Germannameis t | a c tu r r dw i t h \ t r o n gp u r g a t r v ct :o p r e \ c n tg r i p i n g . yellow variety ofthe plant lacksthe anthocyaninpigmentation;the leaves and stemsare a yellowish-greenand the tlowers and berriesyellow. Egyption henbqne Egyptian henbaneconsistsol the dried leavesand llowering tops of History. Belladonnawas probablyknown to the ancientsbut it is not Hyoscyamusnnticus (Solanaceae).The plant is a perentrialabout clearly recorded until the beginning of the sixteenth century. Thc 30-60 cm in height.It is indigenousto desertregionsin Egypt, Arabia, leaveswere introducedinto the Lontlon Pharmacopoeiaof 1809,but lran, Baluchistan.Sind, westernPunjab.and has beenintroducedinto the root was not used in Britain until a liniment preparedfrom it was Algiers and is cultivatedin southernCalitbrnia.In Egypt it is collected introducedby Squirein 1860. fiom wild plantsby Arab shepherds. Macroscopicalcharacters. The drug consistsof leaves.stems,flowers and fiuits. The leavesare usually matted and lbrm a lower propotlion of the drug than in the caseof Europeanhenbane.The leavesarepubescent,pale greento yellowish,rhomboidalor broadlyellipticaland up to about15 cm long. Midrib broad,venationpinnate,marginentireor with aboutfive largeteethon eachside.Petiolealmostabsentor up to 9 cm long. The stemsare greyish-yellow,striated,slightly hairy and hollow. The flowers are shorlly stalked, with large hairy bracts, a tubular fivetoothedcalyx and a yellowish-brown corolla which in the dry drug rnay show deeppurplepatches.The fruit is a cylindricalpyxidium sunounded by a persistentcalyx and containing numerousyellowish-greyto brown seeds.Odour,slightly foetid;taste,bitterand acrid. Microscopical characters. Egyptianhenbaneis easily distinguished and unbranchedglandulartrifrorn H. nigerby the nunterousbr"anched chomes.which have a one- to four-celledstalk and unicellularheads. Additional characters are the striated cuticle, the prisrns of oxalate ,15-110ptm,twin prismsand occasionalclustersand microsphenoids.

Cultivation, collection and preparation. Belladonnais grown fi'om seed.The leavesare said to be richestin alkaloid at the end ofJune or in July, and a sunny position is said to give more active leavesthan a shadyone.Plantsabout3 yearsold are sufficientlylargeto give a good yield of leavesand,if the rootsarebeing collected.it would seemto be 'BelladonnaRoot'). Two bestto replantabouteverythird year (seealso or more crops of leavesmay be collectedannually.Leavesleft in an imperfectly dry statedeteriorateand give off ammonia.They should therefbrebe dried immediatelyafter collectionand be carefully stored. Leavesof a good colour may be obtainedby drying in thin layersstarting with a moderateheat which is gradually increasedto about 60oC and then graduallydecreased. Sometimesthe leavesarebadly attacked by insectsand the rootsby a fungus.

Macroscopical characters. The drug consists of leaves and the smaller stems,the latter seldom exceeding5 mm diameter,together with flowers and fruits as describedabove.If the drug is little broken. the arrangementofthe leavesin unequalpairsmay be seen.The leaves aredull greenor yellowish-greenin colour.the uppersidebeing somewhat darkerthanthe lower. Eachhasa petioleabout0.5 -:l cm long and Constituents. Ahmed and Fahmy fbund about 1.1% of alkaloidsin a broadiy ovate, slightly decunent lamina about 5 25 crr long and the leaves.0.57cin the stemsand 2.0"/cin the flowers. The chief alka- 2.5-12 cm wide. The margin is entire and the apex acuminate.A feu loid is hyoscyaminefbr the isolationof which (as atropine)the plant is llowers and fiuits may be found. If the leavesarebroken,the most useprincipally used. The alkaloidal mixture of plants grown in Af'- ful diagnosticcharactersare the venationand roughnessofthe surface. ghanistanhad the following composition:hyoscyamine75Vc,apoatro- The latter is due to the presenceof calcium oxalate in certain of thc pine 157o,hyoscine 5clr, with smaller quantitiesof noratropineand mesophyllcells which causesminute points on the surfaceof the leaf norhyoscine.A number of non-alkaloidalketones.an acid and sito- as the other cells contractmore on drying. stelol have been characterizedfiom plants raised in Lucknow. India. The formation of alkaioidsin suspensioncell cultureshasbeenwidely Microscopical characters. A transversesectionof the leal ol A. belThe epiderladonnais shownin Fig. 27.94. lt has a bifacial stt'ttcture. investigatedwith variableresults;with callus culturesthe addition of phenylalanineto the medium producedmaximum alkaloid production mal cells have wavy walls and a striatedcuticle (Fig. 27.98). Stomata (3.97ck)whereasisoleucinegavethe greatestgrowth (M. K. El-Bahr et of the characteristicanisocytictype and also some of the anomocytic type are presenton both surfacesbut are most common on the lower. al., Fitoterapia, 1997, 68, 423).

ALKALOIDS

xy ph

a

fr[

Fig.27.9 section of portion of lomino(x200);C, dishibution of idioblosts, surfoce Atropo bellodonno leof.A, Tronsverse section of midrib(x40);B,tronsverse (G)of (ollx2O0);G ond H, Sconningelectronmicrogrophs E, lowerepidermis; F,trichomes viewof leofcleoredin chlorol(x50);D, upperepidermis; of cuficle;c, collenchymo; e, endodermis; glondulortrichomeond epidermolcellswith striotedcuticleond (H)stomoond striotedcuticle.o, Shiotions phloem;m, mesophyll; p, polisode id, idioblostcontoining crystols of colciumoxolote;i.ph,introxylory ox, colciumoxolotecrystols; ep, epidermis; L.Seedond R.Worsley.) loyer;ph, phloem;st,stomo;vt, veinlet;xy, xylem.(Photogrophs, Hairs aremost numerouson young leaves.Someof the hairs areuniseriate,two-to four-celledclothing hairsl othersresemblethesebut have a unicellularglandularhead;while a third kind has a shortpediceland a multicellular glandularhead (Fig. 27.9F).Certain of the cells of the ('sandy') crystalsof spongymesophyllarefilled rvith n.ricrosphenoidal calcium oxalate (Fig. 27.98, C). The midrib is convex above and shows the usual bicollateralvascularbundle. A zone of collenchvma underliesboth epidermiin the region of the midrib.

cium oxalate.They yield aboLrtl,l% of ash and not more than 4clr of acid-insol-rbleash. PrepuretlBelladonnaHerh is the fincl5' porvdereddrug adjustedto 'loss on drying' contain 0.28-0.32% of total alkaloids.Note the fequlrement.

Allied drugs. lndian helladonna front A. acuminattt Royle ex Lindley difl'ersfiorn that delived fiorn A. belladonnain that its f-lowers are yellowish-brownand its leavesbrownish-green, oblong-elliptical and tapering towards both base and apex. It grows wild in the Constituents. The drug lrom A. belladonnucontains0.3-0.60% of Himalayanregionsof northernIndia (1800-3,100m) and is cultivated alkaloids.the chief of which is hyoscyamine.Srnall quantitiesof volatile bases,such as pyridine and N-methylpyrroline,are present, in the Kashmir valley. Atropu haetica Willk. is a speciesnltive to southernSpain and and if not removedduring the assayof the drug by heating,increasethe titration and appearin the result as hyoscyamine.The leavesalso con- northernMorocco: it producesyellow flowers and black berriesand is (scopoletin),and ca1- re-eardedas an endangeredspecies.R. Zitrareet c1. have describeda tain a fluorescentsubstance.B-methylaesculetin

E

PHARMACOPOEIAL AND RELATED DRUGSOF BIOLOGICAT ORIGIN rapid ir?vilro propagationmethod for the plant, and from hairy root cultureshave isolatedtigloylpseudotropine-a new alkaloid not found in the matureplant(PlantCell Rep.,1999,18,4i8). Adulterants. Of the numerous recorded adulterants of belladonna leaves, those of Ph1'trsluccadecandra (Phytolaccaceae)and Ailanthus glandulosa (Simaroubaceae)are perhaps the inost important. In Phltolacca the lamina is denserand less decurent than in belladonna; the epidermalcells have straightwalls, the stomataare of the anomocytic type and some of the mesophyll celis contain bundles of needleshapedcrystalsof calcium oxalate.Ailanthus leavesaretriangular-ovate, have straighfwalled epidermalcells showing a strongly striatedcuticle, cluster crystalsof calcium oxalate,and on both surfaceswhite, unicellular clothinghairswhich arelignified (Fig. 43.3F). Uses. Belladonna leaves are mainly used for internal preparations which areusedas sedativesand to check secretion.Preparationsof the root are mainly used externally. Bellqdonno roof Belladonnaroot consistsof the dried roots or rootstock and roots of At ropa belladonna (Solanaceae). Collection and preparation. Much of the A. belladonLradrug is of small size and poor quality. The firstyear roots are not profitable to collect from the commercial point of view, although they contain a high proportionof alkaloids.The autumnof the third year would seem to be a suitabletime for collection.The rootsareCugup, washed,sliced and dried.

ertiesto other samplesof the enzyme previously described,has been isolatedfrom transformedbelladonnaroot cultures.The pseudotropine could have implications for the formation of calystegines (q.v). Littorine hasbeendetectedin both non-transformedand hairy root-cultures(F. Nakanishiet al., Plant Cell Rep., 1998,18,249). Allied drug. Indian belladonna root from Atropa acuminata (see 'Belladonna under Herb') consistsof brownish-grey roots, stolons. rootstockand stem bases.lt has been describedin detail by Melville. The roots are cylindrical, Iongitudinally wrinkled, occasionally branched,and 0.5-3 cm diameter.Young roots resemblethose of A. belladonnabut older ones show concentriczonationof the secondary xylem. The rootstockis 3-9 cm diameterat the top and bearsthe bases of 1-12 aerial stems.The rootstock,stembasesand stolonsall possess a pith which becomeshoilow in the stem bases.The constituentsare similar to thoseof Europeanbelladonna. Adulterant. The root of Phytolacca decandra (Phytolaccaceae)is sometimesslicedand mixed with samplesof belladonna.It bearslinle resemblanceto belladonnaroot, but a casualandinexperiencedobserver might perhapsmistakeit for piecesof an old belladonnacrown. The transversesectionshowsa numberof concentriccambia,eachproducing a ring of wood bundles.The parenchymacontainsabundantacicular crystalsof calcium oxalate.

DUBOISIAIEAVES

Threespeciesof Duboisia areindigenoustoAustralia and two of these. D. myoporoides and D. leichhardtii, have for over 50 years been a Macroscopical characters. Atropa belladonna r^pidly develops a major world sourceof tropanealkaloids.The third species,D hoplarge branching root. The aerial stemsdie back eachyear and new ones woodii, containsprincipally nicotine and related alkaloids and was 'pituri' by mixarise independently from the large crown. Dried roots of 3-year-old usedby theAustralianaboriginesfor the preparationof plantsareabout3 cm diameterandrootsover 4 cm diameterareexcep- ing powderedleaveswith an alkaline wood ash to form a quid which was held in the cheekpouch. tional. Most commercialdrug is abouthalf this thickness. D. myoporoides,discovered by Robert Brown, naturalist to the The drug is usuallycut into shortlengths,which are sometimessplit Flinders expeditionof 1802,occursalong the east coastofAustralia. longitudinally. The outer surface is a pale greyish-brown.The root where the rainfall exceedsa monthly mean of 5 cm for l1 months of breaks with a short fracture and then shows a whitish or. if overheated during drying, brownish interior. A yellowish-green colour in the the year and where frosts rarely occur.D. leichhardtii was described by Mueller in 1877 and is named after the explorer Ludwig region of the cambiumis often seen. A transversesectionof the bark is nonfibrousand the wood doesnot Leichhardt,who originally collectedthe plant; it occursnaturally in a limited area of south-eastQueenslandknown locally as the South show a radiateappearance. The wood consistsof scatteredgroups of vessels,tracheidsand fibres which are most abundantnear the camb- West Burnett. D. hop-*oodii is of wide distribution in Western and ium; thereis a centralmassof primary xylem (Fig. 42.8G).The exten- CentralAustralia. Of the two tropanealkaloid-containingspeciesD. myoporoidesis sive parenchymaof bark and wood containssandycrystalsof calcium the larger and more densely leaved; both, however, are bushy treesand oxalate and abundantsimple and compound starch grains. The structure gradually changesas the roots pass into rhizome, the have the advantage that in one year repeated harvests can often be wood becomingdenserand exhibiting a distinctlyradiatestructure;the taken from the same plants. For collection, the small branchesare rhizome also shows a distinct pith and internal phloem. The aerial removed, tied in bundles and stood in shedsto dry; the leaves are then easilyremovedby beating. stemsfound on the upper surfaceof the crown are hollow In additionto hyoscineandhyoscyamine,minor alkaloidsoccur in variable amounts and include norhyoscyamine,6B-hydroxyhyoscyamine, Constituents. Atropa belladonna toot contains about 0.4-0.87o of valeroidine, tigloidine, poroidine, isoporoidine, valtropine, 3cx-tigloylalkaloidscalculatedas hyoscyamine(BPC requiresO.4Vo). Samplesof belladonnaroot examinedby Kuhn and Schdfershowed oxytropane,3u-acetoxytropane,3o-nonanoyloxytropane,butropine and 0.3-1.0Vc of alkaloids, of which 82.8-97.3Vo was hyoscyamine, apohyoscine.Two discopine esterswere identified in 1980 in D. leich2.7-1 5 .2Voatropine,and0.0-2.6Voscopolamine.Capillary GLC-mass hardtii and the greenhouseleaveshave yielded calysteginesB,, 82, Ba, spectrometrydata has revealedthe presenceof hygrine, hygroline, cus- C1, and C2 (A. Kato et al., Phytochemistry-, 1997,45,425). Other concohygrine, tropinone, tropine, pseudotropineand nine tropanol esters stituentsinclude the triterpenoidsursolic acid and betulonic acid and a (F. Oprach et al., Planta Med., 1986,513). Other constituentsprevi- numberof recentlyreportedaliphaticconstituents. A number of chemical races occur, parlicularly in D. myoporoides, ously reportedinclude belladonninetogetherwith B-methylaesculetin, and include the well-established'northern'and'southern'raceswhich calcium oxalate and starch. differ in their relative contentsof hyoscine and hyoscyamine,and a A pseudotropine-forming,tropinone reductase(see biogenesisof tropaneaikaloids),not entirely similar in chemicaland catalyticprop- race which containsnicotine and anabasineas principal bases.

il

ALKALOIDS For a numberof years,growershavealsobeencultivatinga hybrid of the collection of the root was formerly accompaniedby specialrites. the two species,the origin of which is doubtful,but which Griffin con- The drug, like belladonna,has long been known to contaln atropine sidersmay derive from the experimentalwork of the CSIRO caried out and the fluorescentsubstancescopoletin.Recent investigationshave in the early I 950s.Establishedpiantationsof the hybrid exhibit no mor- establishedthe presenceof severalother solanaceous alkaloids. phological difTerencesand propagationis carried out vegetatively. In a series of experiments on the hybrid, Griffin and Luanratana (J. Nat. COCAIEAFAND COCAINE Prod.. 1980,43,552:.1982,45,270)have shown that the total alkaloid contentof the leavesdoes not vary throughoutthe year but there is a Coca leavesare derived from shrubsof the Erythroxylaceae,namely decreasein hyoscinecontentfrom Januaryto June(summerto autumn) Erythrorylum coca (Bolivian or Huanuco)andE. truxillense(Perr"rvian or Truxillo), cultivatedin Peru,Bolivia, Colombia and Indonesia. and a gradual increasefrom June to September;the reverseis true for hyoscyamine.Repeatedsprayingsof plants with cytokinin solulion (which also has a beneficial elTecton plant growth), in the lbrm of a sea- History. Cocaleaveshavebeenusedin SouthAmericaasa masticatory weed extract,preventedthe hyoscinedecline.Such treatmentof plants from very e:Lrlytimes.They were formerly reservedfor the soleuseof the could possibly enhancethe hyoscine yield from all-year harvesting. native chieli and Incas.Coca was introducedinto Europeabout 1688and Thereis evidence(Y. Kitamura et al., Phv-tochentistry^,1996,42,1331)cocaine was isolated in 1860.By employing the alkaloid in ophthalmic surgeryin I 884 Carl Koller was the first to introduceit into clinical practhat in the plant the tropic acid moiety of atropinemay be recycled. For reviewscovering tice so heraldingthe era of modem anaesthetics. Addition of putrescineand spermidineto the culture medium of D. m-toporoidesroot cultures has been shown to increasethe hyoscine both the historical and other aspectsof coca seethe specialissueof l/ze (1981),Vol. 3: CocaonclCocaine. Joumal of Ethnophannacoktg,v content(T. Yoskiokaet al., Planta Med.. 1989,55,573). Most of the Australiancrop (some 1200tonnes)is exportedto West Germany,Switzerlandand Japanfor processing.Plantationshave also Collection. In Bolivia and Peru coca is cultivated at an altitude of 500-2000 m. The cultivated plants are usually pruned so as not to beenestablishedin Ecuador. exceed2 m in height. Three harvestsare collectedannually,the first from the pruned twigs, the secondin June and the third in November. Scopolio All speciesof Scopolictinvestigatedappearto contain tropane alka- The leavesare aftificially or sun-driedand packedin bags. loids similar to thosefound in belladonna(q.v.).Although little usedin westel'nEurope,theseplantsconstitutea useful sourceof hyoscyamine and galenicalsin regionswhere the plant is availablelocallry.Scopolia caniolica is a centraland easternEuropeanspeciessomewhatsmaller than belladonna.In shape the leaves resemblethose of belladonna, althoughthey are more lanceolateand translucent.The cuticle is striated but less markedly so than in belladonna,sandy crystals are less numerous,hairsarerareor absent,and stomataarepresenton the lower surfaceonly. The fruit, which is a pyxis, may often be found in the drug. The rhizomes(BPC 1934),which are nearly black in colour and bear numerousdepressedstem scars,are used similarly to belladonna root. In additionto hyoscyamineandhyoscine,otheralkaloidsreported in this speciesare cuscohygrine,3o-tigloyloxytropane.pseudotropine and tropine.S. caucasia,S. lurida andS. tanguticcall appearto be suitable as sourcesof hyoscyamine;the last two also contain 6-hydroxyhyoscyamineand an alkaloid nameddaturamine(anisodine)which is a 'hydroxyhyoscine'.Both thesealkaloidsareproducedcommerciallyin China. The dried rhizomes of S. Japonlca ('JapaneseBelladonna Root') were official in rhe JapanesePharmacopoeia196l; the isolahas beenreportedfrom this tion of steroidalglycosides(scopolosides) species(S. Okamuraet aL.,Chem.Phurnt.Bull., 1992,40,2981). Przen'alskiutonguticais a relatedtropanealkaloid-containingplant and is usedin Tibetantraditionalmedicine.The roots have a high content of hyoscyaminewith total alkaloidsamountingto 1.7-3.87c;6$hydroxyhyoscyamineand small amountsof hyoscineare alsopresent. Mondroke The true mandrake, Mandragora o.fficinarum, is one of several Mediteranean species.It was well known to Dioskurides(see R. T. Gunther'sEnglish edition of The GreekHerbal of Dioscorides,1934, Oxford. UK: OUP). B. P.Jackson,in an investigationof the botanical source of the drug, found that the speciesM. autumnalis ts also involved.The leavesand roots were official in France(1818-1883) and in Spain.The roots occur in fusiform or two-branchedpiecesand their microscopicalstructureand distinctionfrom belladonnaroot has beendescribedby Berry and Jackson(PlantaMed..1976,30,281). The plant is surroundedwith rnuch folklore and superstitionand even

Macroscopical characters. 7. Huanuco or Boliviat't coca leavesare shortly petiolate,oval, 2.5-7.5 cm long and 1.5-4 cm wide. The laminais greenishbrown to brown and glabrous;margin entire.The midrib is prominenton the lower surface, bearsa ridge on its uppel surface,and projects slightly beyond the lamina as an apiculus.The latter is often broken in the commercial drug but the leaves are otherwise fairly entire. The lower surface showstwo, very characteristic,curved lines, one on either side ofthe midrib. Odour, characteristic;taste,at first bitter and slightly aromatic, the alkaloidsafterwardscausingnumbnessofthe tongueand lips. 2. Trttxillo or Peruvian coca leaves are pale green in colour, are mote papery in texture than the Huanuco and are usually broken. Lamina about 1.6*5 cm long; lines on the lower surface usually indistinct. Flowers of a speciesof lnga (Leguminosae,subfamily Mimosoideae) aresometimesaddedto the leaves. 3. Javanesecocc leavesof the Truxillo type were formerly exported for the manufacture of cocaine. Microscopical characters. A transvetsesectionof a cocaleaf shows upper epidermis,palisadeparenchymacontaining prisms of calcium oxalate,spongyparenchymaand a very characteristiclower papillose epidermiswith numerousstomata.The midrib is partly surroundedby an arc of pericyclic fibres, above and below which is a considerable amountof collenchyma.A surfacepreparationof the lower epidermis showsthe papillaeas well-markedcircies,and numerousstomata(Fig. 43.2J1,eachwith four subsidiarycells, two of which have their long axesparallelto the pore. Constituents. Cocaleavescontainabott O.'7-1.57aof total alkaloids, of which cocaine, cinnamylcocaineand q,-truxilline are the most important.They occur in difTerentproportionsin differentcommercial varieties. Javaneseleaves are usually richest in total alkaloids, of which the chief is cinnamylcocaine,while the Bolivian and Peruvian Ieavescontain less total alkaloid but a higher proportion of cocaine. Other substancesisolated from various varieties of the leaves are hygrine, hygroline, cuscohygrine,dihydrocuscohygrine.tropacocaine

PHARMACOPOEIAT AND RELATED DRUGSOT BIQLOGICALORIGIN

:l:rrail::iirll.lirirril,,iall i rllillrlll:ii

(3B-benzoyloxytropane), crystalline glycosidesand cocatannicacid. l-Hydroxytropacocaine(free hydroxyl situatedat a bridgeheadcarE. bon) has beenisolatedas a major alkaloid of greenhouse-cultivated noyogran(fiensevar. noNogranatense:much lower amounts were detectedrn var. truxillenseand in field cultivatedcoca from Colombia 1994,36,351). and Bolivia (J. M. Moore et al.. Phytochemistry-, The leaves also contain essentialoil and as early as 1894 Van Romburghidentified methyl salicylateas a component;this was confirmed (13.67c) in a recent study, together with N-methylpynole (3.77o)and possiblyN,N-dimethylbenzylamine(0.57o)and two dihy(38.9%).The grassyodour ofthe leavesis explained drobenzaldehydes to a large extent by the presencein the oil of trans-2-hexenal(.10.4Va') were and cls-3-hexen-1-ol(.16.1%):no mono- or sesquiterpenes detected(M. Novdk et al., Planta Med., 198'7,53, 113). Although it had been generally assumedthat ecgonine,the basic moiety of the cocaines,was ornithine-derived(Fig.27 .2), the practical demonstrationof the incorporationof the usualprecursorsproved difficult. Then Leete (./. Am. Chem. Soc., 1982, 104, 1403) obtained a significant level of radioactivity in cocaine isolated from Erythroxylumcoca, lhe leavesof which were paintedwith an aqueous solution of Dl-[5-14c]ornithineHCl. The pathway to ecgonine appearsto be similar to that for tropine except that the carboxyl is retainedand the different stereospecificities needto be accommodated. The benzoyl moiety of cocaineis derivedfrom phenylalanine.For work on the incorporationof labelled I -methyl-AI -pyrrolinium chloride into cuscohygrine,indicating the alkaloid to be a mixture of its meso and optically active diastereomers, see E. Leete et al., Phytochemistry,1988,27, 401. Manufacture of cocaine. The crude alkaioids may be extractedwith dilute sulphuric acid or by treatment with lime and petroleum or other organic solvents.Non-alkaloidalmatter is roughly separatedby transferring the alkaloids from one solvent to another.The crude alkaloids are obtained in solid form either as free bases by precipitation with alkali, or as hydrochloridesby concentratingan acidified solution. Pure cocaine is prepared from the leaves, the crude bases or the crude hydrochlorides.The processdependson the fact that cocaine, cinnamyl-cocaineand o-truxilline are closely related derivativesof ecgonine (Fig. 21.2), which is produced by hydrolysing them with boiling dilute hydrochloricacid. Cocaine+ ecgonine+ methyl alcohol + benzoicacid Cinnamyl-cocaine-+ ecgonine+ methyl alcohol+ cinnamicacid -+ ecgonine+ methyl a-Truxilline (y-isoatropyl-cocaine) alcohol+ cx-truxillicacid

The ecgonine hydrochloride is purified and converted into the free base.This is benzoylatedby interaction with benzoic anhydride and the benzoylecgoninepurified. The benzoylecgonineis methylated with methyl iodide and sodium methoxide in methyl alcohol solution, to give methylbenzoylecgonine or cocaine. The latter is converted into the hydrochloride and purified by recrystallization. Much illicit cocaine is extracted locally in South America and despite the unsophisticatedmethods employed a high degreeof puritl, can be attained. In view of the importance of quantitatively determining cocaine and its metabolite,benzoylecgonine,in body fluids, etc., many assaysare availablefor thesealkaloids. Allied species. There are over 200 species of Erythro4tlun found throughout the tropical and pantropicalregions of the world. Few of the non-cocaine-producingspecieshave been systematicallyexamined but the majority of thosethat havecontaina rangeof tropanealkaloids(W. C. Evans,"/.Ethnopharmacol.,1981,3, 265 and for Pt. 12 of a further series 1053).Recent of papersseeP.Christenet al., Phytochemistry,7995,38, studieshave revealednew alkaloids from E lucidum (A. Brachet et al.. Phytochemistry,1997,46,1439) and from E. moonii (Atta-ur-Rahmaner al., Phlttochemistry,1998, 48,311). Three new alkaloids have recently been characterizedfrom E. 4eylanicum,the one speciesendernicto Sri Lanka (G. Bringmannet al., Phytochemistry,2000,53,409). Uses. Cocaineand its saltswere the earliestof the modern local anaesthetics but, becauseof their toxic and addictive properties,their use is now almost entirely confined to ophthalmic,ear,noseand throat surgery.

Colystegines These relatively new alkaloids are trihydroxy-, tetrahydroxy- or pentahydroxy derivatives of nortropane.They were originally isolated from the roots of the bindweed Calystegia sepium and given the names (Fig. 21.2) and calystecalystegineA'3 (a 1,2,3-trihydroxynortropane) gine 82 @ 1,2,3,4-tetrahydroxynortropane). By 1998 the structuresof nine such alkaloids had been elucidated including the 3-O-B-oglucopyranosideof calystegineB 1. In a chemotaxonomicstudy of the Convolvulaceaeinvolving the GC-MS analysesof 65 species,T. Schimminget al. (Phytochemistry,1998,49,1989)reportedthe occurrence of 1 to 5 calysteginesin 30 speciesbelonging to 15 genera. Calystegineshave also beenreportedin the Solanaceaeand Moraceae including belladonnaand hyoscyamusroot cultures (B. Driiger and A. Schaal, Phytochemistry, 1994, 35, 1441). R. J. Nash et a/., (Phytochemistrr-,1993,34,1281) found thesecompoundsto be present in the tubers and leavesof potato plants and that thesealkaloids can be

coocH3 oco.c6H' c-Truxillicacid

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ALKALOIDS isolatedfrom certainmoths and butterflies.the larvaeof which t-eedon the plant. Pharmaceutically.interestlies in the calysteginesbecausethey are potentinhibitorsof glycosidases(R. J. Molyneux et al.. Arch. Biochent Biophl'sics,1993,304, 8l) making them possiblecandidatesfor the developmentof a drug for the treatmentof AIDS (cf the tlihydroxyindolizidine alkaloidscastanospermine and swainsonineand the tetfahydroxypynolizidine alkaloid australine).

Toboccoolkoloids The principal alkaloidsof the -eenusNicoriana have a pyridine moiety associatedwith eithera pyrrolidinering (ornithine-derived)or a piperidine ring (lysine-derived).The fbrmer group is represented by nicotine (Flg. 27.2) and the latterby anabasine(Fig 27.1I ). Although, with the exceptionindicatedbelow, no drugs are derived from thesealkaloids,they have beenextensivelystudiedin relationto tobacco manufactureand smoking, and as insecticides(see Chapter 4l). Consequently,much is known of their plant biochemistry and geneticsof formation. A recent pharmaceuticalintroduction is that of nicotine chewinggum, nasalsprayor patch.intendedto help smokerswho want to give up smokingbut who experiencegreatdilTicultyin so doing becauseof their nicotinedependence.

frequentlyoccur as esters,being linked with characteristicmono- or dibasic acids called the necic acids. They are biosynthesizedfrom omithinevia a symmetricalintermediateandlabellingexperimentshave shownthe involvementof putrescincand homospermidine.Two molecules of putrescineare requiredto form one of homospermidine.This pathway has been supportedby the isolation,partial purification and characterization of the NAD+-dependentenzymehomospermidinesynthase, the first pathway-specificenzyme in pyrrolizidine alkaloid biosynthesis(F. Bijttcher et ul.. Ph-,-tochentistl',1993,32,679). The componentsof senecionineareillustratedin Fig. 27.10.The hepatotoxic propertiesare believedto ariseby breakdownofthe alkaloidsin the liver to stronglyalkylatingpyrrole esters. For reportson pyrrolizidine alkaloidssee:T. Hartmannand L. Witte (1995). Alkaloids, Chemical and BiologicaLPerspectives(ed. S. W Pelletier).Vol.9. New York: Wiley. p 155. A generalreview: K. Ndjoko et ol., Pl(tntaMed.. 1999,65,562. Determinationin Senecio soecies.

As the next homologueto ornithine.Iysineand its associatedcompoundsgive rise to a numberof alkaloids.someof which are analogous to the ornithine group (see Fig. 27.11). The lycopodium alkaloidsare also derivedfiom lysine.Although in somecases.such PYRROLIZIDINE ALKATOIDS as the quinolizidinelupin alkaloids,Iysineis incorporatedvia a symmetrical precursor,e.g. cadaverine.in the majority of examples Althoughthesealkaloidshaveat presentno greatmedicinalsignificance (anabasine.sedamine,N-rrethylpelletierine)the incorporationis they areimportantin thatthey constitutethe poisonoushepatotoxiccon- asymmetric.In general.fbr the simple cx,-subsrituted piperidines,the stituentsof plantsof the genusSenecio(Compositae),well-known fbr C-2 of lysine becomesthe point of attachmentof the cxside-chain. their toxicity to livestock.Someofthe alkaloidsalsoshow crrcinogenic (For researchin this area and references.seeE. Leete, Nat. Prod., "/. and mutagenicproper-ties and havecausedconcernin that they occur in 1982.45. 197: T. Hemscheidtand L D. Spenser,J. Ant Chen. Soc., quantities small in some herbal products such as comfiey 1 9 9 0 , 1 1 2 . 6 3 6 0 . ) (Boraginaceae) and coltsfoot(Compositae).Thesealkaloidsare known The wide distributionof thesebasesthroughoutthe plant kingdom is to havean ecologicalrole in somespeciesofbutterlly affbrdingprotec- illustratedby the drugswhich fbllow. tion to someandconvertingto femaleflight arrestants in others.Indicine N-oxide hasantitumourproperlies(q.v.).Australine.recentlycharacterLOBETIA izedfrom the seedsofthe legurninoustreeCastanosperniltm ttustrale,is a tetrahydroxypyrrolizidine alkaloid.It was obtainedby useolrepeated Lobelia BHP; BP 1988(Lobelia Herb. lndian Tobacco)consistsof the preparativecentrifugalTLC. Like the polyhydroxyindolizidinealka- dried aerial parts of Lobelin inflata (Campanulaceae), an annualherb loids it exhibits glycosidaseinhibitory activity (for lurther detailssee indigenousto the easternUSA and Canada.It is cultivatedin the USA R. J. Molyneux et ol., J. Nat Prod., 1988,51, ll98). The alkaloids and Holland.

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