RELATIONSHIPS BETWEEN PLANT FOLKLORE AND ANTITUMOR ACTIVITY: AN HISTORICAL REVIEW

2005·14.1 MB·English

by  Richard W Spjut

RELATIONSHIPSBETWEENPLANTFOLKLORE
ANDANTITUMORACTIVITY:ANHISTORICALREVIEW^
RichardW.Spjut^
WorldBotanicalAssociates
P.O.Box81145
Bakersfield,California93380-1145,U.S.A.
www.Worldbotanical.com
ABSTRACT
iTnheexNpaetriiomneanltaClantcuemrorInsstyisttuteem'ss((aNcCtIi)verpelcaonrtds)t,:>l1p9l6a0n-t1s97th4a,twhaasvecosmhpoawrnedsiwginitfhicsapnetciienshaibnidtogreyneerfafemct
referencesonmedicinalfolklore,includingpoisonousplants,todeterminewhethertheirpercent-
agesofactiveplantsweresignificantlygreaterthanthosescreenedatrandom(10.4%).Thepercent
activespeciesinmedicinaland/orpoisonousreferencesingeneralwereioundtobe1.4to2.6times
greater,whilethenumberanddifferentkindsofmedicinalusesappearrelatedtogeographicaldata
ofspeciesthatalsoindicatemedicinalplantswerescreenedmorethoroughlybecauseottheirwide-
spreadoccurrence.Thebestcorrelationisseenwithpoisonousplants,includingmedicinalplants
thatsuggestamoderatetostrongtherapeuticeffect;theirpercentagesoiactivespecieswerenearly
three(29.3%,anthelmintics)tolourtimes(4.5.7%,arrowandhomicidalpoisons)greaterthanplants
screenedatrandom.Selectionofplantsbasedstrictlyonuseinfolkmedicinewouldprobablyben-
efitnew(start-up)screeningprograms,whereasinthelong-term,itappearsmorecosteffectiveto
systematicallyscreenthebroadestdiversityofplantsreadilyavailablesincethecommonmedicinal
specieswouldbecollectedirregardless.Asystematiccollectionstrategycouldgiveemphasistogen-
erathathavenotbeenexhaustivelystudied,especiallytospecieswithruedicinalusesthatindicate
toxicityorareconsideredpoisonous.
RESUMEN
ElregistrodeplantasdelNationalCancerhistitute(NCI)1960-1974,quehanmostradounefecto
inhibidorsignificativoensistemastumoralesexperimentales(plantasactivas),secompararoncon
generosyespeciesqueaparecenenreferenciasdemedicinapopular,incluyendoplantasvenenosas,
paradeterminarenquemedidalosporcentajesdeplantasactivaseransignificativamentemasaltas
quelasinvestigadasalazar(10.4%).Elporcentajedeespeciesactivasrelerenciadascomomedicinales
y/ovenenosasengeneralseencontroqueerade1.4a2.6vecesmayor,mientrasqueelnumeroy
diferentestiposdeusosmedicinalesparecenrelacionadoscondatosgeograficosdeespeciesque
tambienindicanquelasplantasmedicinalesiueroninvestigadasmasminuciosamentedebidoasu
ampliadistribucion.Lamejorcorrelacionseapreciaconlasplantasvenenosas,incluyendolasplantas
'AsummaryofthedatainthispaperwaspresentedattheSocietyforEconomicBotanySymposiumonPlants
AndCancerheldinBaltimore,August1975.AnalternatepaperwaspublishedInCancerTreatmentReportsin
August1976(Spjut&Perdue.Vol.50,8:979-985).LeftoutwerealldataanddiscussiononQuisumbing's(1951)
MedicinalPlantsofThePhilippines,reviewsongenerawithgeographicallydisjunctusesofmedicinalspecies,
andactivityaccordingtothetumorsystemsemployed.
^USDAAgriculturalResearchService,MedicinalPlantResourcesLaboratory,Beltsville,MD20705.TheNCItermi-
natedtheiragreementwiththeARSinOct1982,SpjutlefttheUSDAinMarch1997.WorldBotanicalAssociates,
Bakersfield.CA93380-1145.
SIDA21(4):2205-2241.2005
2206 BRIT.ORG/SIDA21(4)
medicinalesqueparecentenerunelectotcrapeuticodemoderadoaluerte;losporcentajesdeespecies
activastuedccercadetres(293%,antihelminticos)acuatroveces(45.7%.venenosparaIlechasy
homicidios)nnu'ort[uclasplanusmvcstigadasalazar.Laselecciondeplantasbasadaestrictamente
enelusoenmedicinapopulai'probablcmentcsenabencliciosaparalosnuevosprogramasde
investigacion,inientrasquealargocermmo,pareceteneruncostoelectivomayorlainvestigacion
sistematicadeunadiversidaddcplantasfacilmentedisponiblesyaquelasespeciesmedicinales
comunespuedcncolcctarseencualquierparte.Unaestratcgiadecolectasistematicapondriacnlasis
engencrosi.|uenohayansideestudiadose.Khaustivamentc,yesiiecialmcnteenespeciesconusos
medicinalest|ucindic|uentoxicidadoqueseconsidercnvencnosas.
INTRODUCTION
TheUSDAAgriculturalResearchService(Ai^S)wasamajorsuppHcrofplant
sampleslortheNationalCancerInstitute(NCI)CancerChemotherapyScreen-
ingProgramfrom1960-1982.Theobjectiveofthisprogramwastoidentifynovel
chemicalstructuresproducedbyplantsthatwouldbeusefulintreatmentof
cancerTwomajordiscoverieso(novelanticancerdrugsfromthisperiodwere
taxol(Wanietal.1971),isolatedfroinstem-barkof TaxushreviJoUaNutt.
(Taxaceae),mitiallycollectedinWashington,August1962,followeddiscovery
ofconfirmedantitumoractivityinKBCellCulture(KB),July1964(NCICPAM,
1977), and camptothecin(Wallet al. 1966), isolated from Camptotheca
acuminaUiDecne.(Nyssaceae),basedonfruitsamplescollectedmSeptember
1961tromaUSDAPlantIntroductionStationinChico,California,andreported
tohaveconfirmedantitumoractivityinL-1210Leukemia(LE),July1962(NCI
CPAM1977).Semi-syntheticderivativesofcompoundsfrombothspeciesare
currentlyemployedtotreatvariouscancers(Craggetal.1996).Thecommer-
cialdevelopmentoftheseanticancerdrugs,however,didnotoccuruntilthe
1990s.In1986,theNCIre-developeditsbiodiversityscreeningprogramofnatu-
ralproducts(Boyd1992;Craggetal.1996;Newmanetal.2003);however,the
acquisitionofplantsamplesfortheNCIscreenwassuspendedin2004.
InAugust197.5,asymposiumon"PlantsandCancer"washeldinBalti-
more,MDattheAnnualMeetingoftheSocietyforEconomicBotany.Thecon-
tributorsincludedmanyscientistsactivelyinvolvedintheNCIsearchofnew
anticancerdrugsfromplantproductswhohadagreed,inadvance,toprovid-
ingaresearchcontribution.Myassignedstudywas"PlantFolklore:AToolfor
PredictingSourcesofAntitumorActivity?Othercontributedpaperswere"Pro-
curementofPlantMaterialsforAntitumorScreening"(Perdue1976),"Prepara-
tionofPlantExtractsforAntitumorScreening"(Statz&Coon1976),"Bioassay
ofPlantExtractsforAnticancerActivity"(Abbott1976),"IsolationandChemi-
calCharacterizationofAntitumorAgentsfromPlants"(Walletal.1976),"Types
ofAnticancerAgentsIsolatedfromPlants"(Hartwell1976),"Distributionof
AnticancerActivityin1ligherPlants"(Barclay&Perdue1976),"NovelPlant-
DerivedTumorInhibitorsandTheirMechanismsofAction"(Kupchan1976),
"PharmacologyofAntitumorAgentsfromHigherPlants"(Siebcretal.1976),
SPJUT,HISTORICALREVIEWOFPLANTFOLKLOREANDANTITUMORACTIVITY 2207
and"PlantProductsinCancerChemotherapy"(Carter1976).Theseandothers
werepublishedcollectivelyinCancerTreatmentReports,editedbyRobertE.
PerdueJr,andJonathanL.Hartwell(Vol.60,No.8,1976).
Uponinvestigatingtherelationshipsbetweenantitumoractivityandplant
folklore,Ifeltthatplantsusedinfolklorewerenotgoingtoleadtodiscoveryof
novelcompoundsanymorethanasystematicsamplingoftheworldsplant
diversitybasedontaxonomy,theapproachthathadbeeninpractice14years.
Therefore,inordertoshowthis,themostcommonmedicinalusesofplants,
andalsopoisonousplants,wouldneedtobemvestigated.Duringthecourseof
thestudy,theresultsontheNCIactivespeciesfoundinliteratureonmedicinal
andpoisonousplants,incomparisonstothosescreenedatrandom,raisedmore
questionsthancouldbeanswered,includingtheoneoriginallyproposed.The
SpjutandPerdue(1976)paperexcludedmuchdatainanothermanuscriptthat
hadbeencompletedandpeerreviewed.
Afternearly30years,theunpublisheddatastillseemrelevanttopresent
daystudiesinethnobotanyandpharmacology,particularlytherelationship
betweenantitumoractivityandfolkloreindicatmgplanttoxicity;therefore,this
paperwillfocusonthatrelationship,includingalsodatafromSpjutandPer-
due(1976).Anotherimportantrelationshipinvolvesthemultipleusesforalarge
numberofwidelydistributedspecies;theirimpactontheapparentcorrelation
betweenantitumoractivityandmedicinalfolklorewillbediscussed.Addition-
ally,Spjut(1985)reviewedtherandomscreenmethodologyindetailwithrefer-
encetounpublisheddataonThePhilippinemedicinalplants;thesedatawill
bepresentedinthispublication.
MATEI^IALSANDMETHODS
—
LiteratureSurveys. Thispaperdealswithdatacompiledfromliteratureand
theNCIplantscreeningprogrampriorto1977.Folkloreandplantsinthisstudy
werelimitedtoliterarysourcesforevaluatingmedicinalusesandpoisonous
effectsofhigherplantsinmanandanimals.Includedareplantsbelievedtohave
medicinalorpoisonousproperties,andthescientificliteraturedealingwith
activechemicalagentsinconfirmedpoisonousandmedicinalplants.Botani-
caldataandthereferencescited,includingthenomenclatureofplants,arenot
updatedsincethispaperwaspreparedandlastreviewedmJuly1976;however,
inregardtopharmacologicaldataoncompoundsthatwereisolated,morere-
centreferencesareprovided.
Eightcompendiaonmedicinalandpoisonousplantswereemployedto
identifywhichoftheirgeneraandspecieswereactiveintheNCIprogram:Har-
din&Arena(1974),Hartwell(1967-1971),Kingsbury(1964),Krochmal&
Krochmal(1973),Quisumbing(1951),Trametal.(1957),Webb(1948),andWeiner
(1972).Oneofthese,Quisumbing(1951),wasfurtherutilizedtodetermine
whetheraspecificmedicinalusewasmorecloselycorrelatedwithantitumor
2208 BRIT.ORG/SIDA21(4)
activity.Becauseantitumoractivityappearedtocorrelatewithawidevariety
ofmedicinaluses,additionaldatafromQuisumbing(1951)werecompiledand
analyzedinregardtomultipleusesof plantsasrelatedtotheirgeographical
distribution.Additionallywe(Spjut&Perdue1976)preparedourowncompila-
tiononplantsusedas(1)anthelmintics,(2)fishpoisons,and(3)arrow,ordealand
homicidalpoisonstodeterminewhethertherewasacorrelationbetweenantitu-
morAaccttiivvietyspaencidesp.l—antAntoxaicctiitvyeisnpceocnitersaisstdteofimneeddicaisnaolneplraenptrseisnengteenedrably.oneor
moreextractshavingshownasigniiicantinhibitoryelfeetinanytumorsys-
temusedintheNCIpreliminaryscreen;thesewereprimarilyKBCellCulture
(humanepidermoidcarcinomaolthenasopharynx,KB,1960-1982),P-388Leu-
kemia(PS,1968-82),LewisLungCarcinoma(LL,1962-66),WalkerCarcinoma
256(WA,1966-69),Sarcoma180(SA,1956-62),Adenocarcinoma755(CA,1956-
62)andL-1210Leukemia(LE,1956-71)(Abbott1976;Gcranetal.1972;ilartwell
1976;Suffness&Douros1979).TheNCIprovidedaprint-outoftheiractivespe-
cieslorthisstudy;additionally,anotherprintoutindicatingtumorsystemsfor
theconfirmedactivespecieswasconsulted(NCICPAM1977).
Activeagentshaveincludedabroadspectrumof compounds(Hartwell
1976),someofwhichwereprecludedfronifurtherscreening(e.g.,tannins,phy-
tostcrols)bychangesmadeintheextractionprocedureandtumorassays
(Llartwell1976);thus,theNCIscreenevolvedtobecomemoreselectiveiniden-
tifyingactivecandidatesfordrugdevelopmentbyeliminatingclassesofcom-
poundsnotconsidered useful fortreatingcancer(Hartwell&rAbbott1969).
Duringthe1960s,tannins—inaqueousextractsfromawidevarietyofplants-
wereIrequentlyactiveinWA,butalsoinCA,LLandSAtumors;atotalof164
species,representing7.7%ofallactivespecies(2,127)inthisstudyweretannin
actives(Barclay&Pcrduel976;Hartwell1976).Later,tanninswereextracted
outbeforetesting,whiletumorsinsensitivetotanninsweresubsequentlyem-
ployed(Hartwell 1976).Consequentlymanyvariablesarerepresentedinthe
definitionol anactivespecies,suchasdifferencesinextractionprocedures,
quantityandkindoftumorsystemsemployed,parametersthatdefineactivity
fromtestingextracts,andwhetherspecilicplantpartsscreenedcorrespondto
thoseemployedinfolklore.Nevertheless,itisfeltthatallplantsregardedactive
l3ytheNCIfrom1960-1976arevalidformakingcomparisonswithfolkusesof
plants.
ComparisonsbetweentheNCIactivespeciesandthoseintheliterature
consideredtaxonomicsynonymsandcloselyrelatedspecieswhenknown.For
instance,theNCIactivespecies.Thaiictrumpolycarpum(Torr)S.Wats.,based
onasamplecollectedandidentifiedbyAS.BarclayfromsouthernCalifornia
in1962,wasnotfoundintheliteraturereviewedtohavemedicinalorpoison-
ousreports;however,thisspeciescouldbeinterpretedasasynonymofT.fendlcri
Engelm.(Munz1959),onethatwasreportedlyusedinmedicinebytheIndian
SPJUT,HISTORICALREVIEWOFPLANTFOLKLOREANDANTITUMORAQIVITY 2209
TribesofNevada(Trametal.1957).Basedontaxonomy,I.polycarpumiscon-
sideredamedicinalplant.
Activegenus.Comparisonswerealsomadeatthegenuslevel;however,the
sizeofthegenusvaries—fromjustonespecies(e.g.,Camptotheca)tomorethan
1,000species(e.g.,Euphorbia);Willis(1922)haddetermmedthat47%ofall
generaaremonotypic,17%havetwospecies,8%havethreespecies,andthere-
maining28%havefourormorespecies.Anactivegenusisonewithoneormore
activespecies.Becausemostgenerahavemorethanonespecies(53%),theper-
centagesofactivegenerawillbehigherthanactivespecies.Also,whenmore
thanonespeciesinanactivegenusisreportedlyusedmedicinallyand/orpoi-
sonous,therelationshipbetweenantitumoractivityandfolklorewillappear
closer,orliebetweenthepercentagesofactivegeneraandactivespecies.
RandomScreen. TherationaleoftheNCIscreenhasbeentoregardany
speciesasapotentialsourcefornovelanticancerdrugs;thus,screeningofplants
hasbeenconsideredrandom.Inpractice,however,collectingwasnotpurely
random.Onereasonisthatitisnotpossibletocollecteveryplantspeciesen-
counteredinthefield,becausethequantityofdryweightneededmaynotbe
practicaltoobtain.Anotheristhatgeographicsamplinghasnotbeenunilorm
forpoliticalandeconomicreasons.
ThenumberofgeneraandspeciesscreenedandactiveintheNCIprogram
wasdeterminedbyA.S.Barclayforthesymposiumon"PlantsandCancer"at
theSocietyforEconomicBotanymeetinginBaltimore,August1975.fiisdata
accountedforallspeciesandgenerascreenedbytheNCI—uptotheendol1974,
takingintoconsiderationsynonymsandsamplesthattheNCIacquirednot
onlyfromtheUSDA,butfromallcontractors.Histabularsummaryisrepro-
ducedhere,Table1(Barclay&Perdue1976).
Thepercentagesforactivegenera,26.0,andspecies,fO.4,arethebasesfor
makingcomparisonstothoseinfolklorereferences;however,itmustbekeptin
mindthatthenumbersforactivespeciesandgeneraarecumulative;i.e.,they
donotrepresenttheactualfrequencyatwhichactivityoccurs.Thisisbecause
somespecieshavebeenscreenedmorethanonce,orhaveincludedmoreplant
partsthanothers,thus,havehadmoreopportunitytoshowactivity—alsokeep-
ingmmindthattheNCIscreenhasbecomemoreselectiveovertime.
GENHRALSURVEYS
TheNCIcomputerrecordofactiveplantspecieswascomparedwithspecies
andgeneracitedinindicesortextsofeightcompendiatodeterminewhich
haveshownantitumoractivity(Table2).Withtwoexceptions,activespecies
weref.4to2.6timesmorefrequentinreferencesonmedicinaland/orpoison-
ousplantsthaninplantsscreenedatrandom,whileresultswithactivegenera
weremoreconsistent—atnearlydoublethatoltherandomscreen.
Thegreatervariationatthespecieslevelformedicinalplantsispartlydue
2210 BRIT.ORG/SIDA21(4)
TARir1.NCIoverallscreeningdataforvascularplants(1960-1974),
NumberScreened NumberActive %Active
Genera 4,716 1,225 26.0
Species 20,535 2,127 10.4
tomanyspeciesnotscreened,incontrasttohigherpercentagesofgenera
screened.Foronereference,Quisumbing(1951),itwasdeterminedthat626of
the855speciesweretested;thus,insteadofthe16.4%activeofthoserecorded
(855),22.4%ofthosespeciesactuallyscreened(626)wereactive—nearlydouble
thatoitherandomscreen.
Inregardtothewiderangingvaluesseenforpoisonousplants,thelower
percentageol9.2%activespeciesinWebb(1948)seemsrelatedtomanyspecies
thataresuspectedtocausepoisoningoflivestock.Whendatafromthesame
referencewasrestrictedtospeciesthatwerereportedtobepoisonousandalso
usedmedicinally,thepercentactivespecieswasnotablyhigher,18.9%.These
datasuggestthatplants,bothpoisonousandusedmedicinally,aremorelikely
toshowantitumoractivitythanthosestrictlyusedmedicinally.Also,datafrom
otherrclerences(Kingsbury1964;Hardin&Arena1974)hadmoreplantscon-
firmedtobepoisonous,whichinHardinandArena(1974)wererestrictedto
thosetakeninternally(Spjut&Perdue1976).Thehigherpercentagesofactive
species(21.5%,41.1%)andgenera(56.4%,66.4%)inthesereferencesonpoison-
ousplantsindicatethattoxicityisafactorintheapparentcorrelationbetween
antitumoractivityandplantsgenerallyusedinmedicinalfolklore.
ActivePlantsAcc:ordingtoNumberandKindsofMedicinalUses
Quisumbing(f951),inhisMedicinalPlantsojthePhUippincs,pro\'idedspecies
indicesfor116differentcategoriesoftherapeuticusesandfor111differentkinds
ofspecilicdiseases,atotalof227differentmedicinalapplicationsfromwhich
90wereselectedonthebasisof 19ormorespeciesbeinglistedtodetermine
whetherantitumoractivitywasmorecloselycorrelatedwithaparticularthera-
peuticeffect(Appendix1,62medicinalapplications)orspecificdisease(Ap-
pendix 11,28medicinalapplications).Whatwefound,however,wasabroad
correlationwithallmedicinalapplications(AppendixI,II).Thisbroadcorrela-
tionappearsrelatedtoalargenumberofwidelydistributedspeciesforwhich
manyhaveprobablybeenscreenedmorethanoncebytheNCI,whileacorrela-
tionbetweenantitumoractivityandtoxicityisalsoevident.Theserelation-
shipswillbemadeapparentinthedataanddiscussionthatfollow.
Quisumbing(195f),inreportingon855speciesin580generaandf43families
ofvascularplantsinThePhilippines,didnotlimithisreviewtomedicinaluses
withinThePhilippines.HealsodrewonliterarysourcesoutsideThePhilippines.
SPJUT,HISTORICALREVIEWOFPLANTFOLKLOREANDANTITUMORAQIVJTY 2211
Table2.Numberandpercentofactivegeneraandactivespeciesformedicinalandpoisonousplants
ineightselectedreferences.
Reference Genera Genera %Genera Species Species %Species
Listed active active Listed active active
MedicinalPlants
Krochmal(1973) 207 131 63.3 251 67 26.7
Quisumbing(1951) 580 271 46.7 855 140 16.4
Trainetal.(1957) 142 77 54.2 214 32 15.0
Webb(1948) 398 228 57.3 529 87 16.5
Weiner(1972) 285 156 54.7 388 73 18.8
PoisonousPlants
Hardin&Arena(1974) 113 75 66.4 141 58 41.1
Kingsbury(1964) 282 159 56.4 488 105 21.5
Webb(1948) 433 211 48.7 760 70 9.2
PoisonousPlantsusedMedicinally
Webb(1948) 229 153 66.8 196 37 18.9
PlantsUsedAgainstCancer
Hartwell(1967-1971) 1,201 480 46.5 2,725 314 17.3
(1,033 (tested) (1,815 (tested)
tested) tested)
Thus,manyplantsnotknowntobeusedmedicinallyinThePhilippineswere
includedsolongastheplantoccurredthere,apracticenotuncommonlyem-
ployedbymanyethnobotanistsinothergeographicstudiesofmedicinalplants.
Nevertheless,theresultisthattherearemanywidespreadspeciesrepresented.
ThisISevidentinpartbyfindingthat8%ofallspeciesinQuisumbing(1951)
areendemictoThePhilippines,basedongeographicaldatahealsoprovided;
thus,92%ofthespeciesinQuisumbing(1951)extendbeyondThePhilippines.
Thedistributionofendemicspeciesaccordingtothenumberofusesis
showninFigureI.Among110speciesinQuisumbing(1951)listedforonlyone
medicinalapplication,25%werefoundtobeendemictoThePhilippines,fol-
lowedbyasharpdeclineforthosereportedundermultipleapplications~-15%
forplantslistedundertwomedicinalapplications,8%forthreemedicinalap-
plication—tononefoundundernineormoremedicinalapplications.Itiscer-
tainlynotsurprisingtofindthatnarrowergeographicallydistributedspecies
havefewermedicinalreports.
However,theextenttowhichmedicinalspeciesarereportedformanydiffer-
entusesisperhapsnotfullyrealizedbymanyethnobotanists.The808specieslisted,
amongthe90medicinalapplicationsselectedfromQuisumbing(1951),ac-
countedforawhopping,5,843speciesentries(meaningthatmanyofthe808
speciesareusedformorethanoneapplication),thedistributionofwhichis
showninFigure2.Asanaverage,50%ofthespeciesreportedunderanyone
2212 BRIT.0R6/SIDA21(4)
ENDEMICSPECIESand MEDICINALAPPLICATIONS
%EndemicSpecies
30-
25
20-
;"::•:•:
15
imllIii 11
10- ii 8
n-imm::i::i;,II':f:t:::::•::•::::;:::::::::m*<::-'-::;':a::;=:•:;:\:i-SS5iSS-iSiBri-Si3S:::::-; 9 10 111 1215 116-
MedicinalApplications
Fig.1.PercentendemicspeciestoThePhilippinesaccordingtonumberofdifferentmedicinalapplicationsbasedon90
of227medicinalapplicationsinQuisumbing(1951).Thenumberofmedicinalspeciesforeachnumberofusesisshown
inFig.2.Of110speciesreportedlyusedforonlyonemedicinalapplication,25%wereendemictoThePhilippines;for
specieswithtwomedicinalapplications,15%wereendemic,etc.,tonoendemicsforspeciesreportedtohavenineor
moremedicinalapplications.GeographicaldataarebasedonQuisumbing(1951).
medicinalapplicationwerealsofoundunder11ormoreothermedicinalappli-
cations.
Theextentolthewidespreadoccurrenceformanyofthemedicinalplants
reportedbyQuisumbing(1951)isfurtherevidentbypercentspeciesscreened
accordingtothenumberofusesrecorded.Figure3,andthefactthatrelatively
fewspecieswereactuallycollectedfromThePhilippines.Someofthemedici-
nalapplicationsinthehighermultipleusecategorieswerecombinedtoobtain
amoreec|uitablenumberofspeciesforeachcategory.Theresultsshow,asone
mightexpect,adefinitecorrelationbetweenthenumberol usesandpercent
speciesscreened,increasingfrom45%forspecieswithonlyonemedicinalap-
plication,to99%lorthosewith16ormoremedicinalapplications.Plantswere
procuredlargelyIromtheUnitedStates,Australia,NewZealand,Fiji,Taiwan,
India,Turkey,Ethiopia,Kenya,Tanzania,SouthAfrica,Ghana,Mexico,Panama,
Colombia,Brazil,andPeru.Small numbersofcollectionswerealsoobtained
fromothercountries;seealsoprocurementmapinPerdue(1976).
Forthe90selectedmedicinalapplicationsfromQuisumbing(1851),626
speciesm531generawerefoundtohavebeenscreenedofwhich140species
SPJUT,HISTORICALREVIEWOFPLANTFOLKLOREANDANTITUMORACTIVITY 2213
Species SPECIES and MEDICINAL
120 APPLICATIONS
100
80
60
40
-
20
i^^
rpfiijij^f rn
12 3 4 5 6 7 8 9 1011 1213 1415IB 171819 202122232425262728293031
MedicinalApplications
Fig.2.Anumericaldistributionofspeciesaccordingtonumberofmedicinalapplicationsforatotalof90differentl(inds
ofmedicinalapplicationsthatincluded808speciesinQuisumbing(1951).Thenumberofspeciesforeachnumberof
medicinalapplicationsdecreasesfrom11 speciesusedforjustonepurpose,toonespecies,ArtemisiavulgarisL,cited
under31differentmedicinalapplications.
(22.4%)in265genera(49.7%)wereactive(AppendixIII);additionally,40%of
the140activespecieswerefoundtohave12ormoremedicinalapplications.
Onemedicinalapplicationwithnotablyhighpercentagesofactivespeciesand
generawasplantsusedagainsthemorrhoids,.35.3%(24)ofthe68speciesand
72.1%ofthe61genera.
Areplantsusedfortreatmentofhemorrhoidsmorecloselycorrelatedwith
antitumoractiveplantsthanplantsusedforotherpurposes?Statistically,the
distributionofactivegeneraandspeciesforthemedicinalapplicationsin
Quisumbing(1951)mightbeexpectedtofollowabell-shapedcurvedistributionin
whichtherewillbehigherthanaverageaswellaslowerthanaveragepercentages
ofactivespecies(andgenera).Thecategorieswithhigherpercentagesofactive
specieswouldalsobeexpectedtohavemorewidelydistributedspeciesbasedon
datapresentedinFigures1-3andtheabsenceofplantcollectionsfromThePhilip-
pinesasalreadyindicated.Indeed,among68specieslistedbyQuisumbing(1951)
forplantsusedagainsthemorrhoids,75%(51)werereportedfor11ormoreother
medicinalapplications,whichincluded23ofthe24activespecies.Therefore,it
cannotbeconcludedthatplantsusedforaparticularremedysuchashemorrhoids
aremoreHkelytoshowantitumoractivitythanplantsusedforotherpurposes.
2214 BRIT.ORG/SIDA21(4)
SPECIESTESTED and MEDICINALAPPLICATIONS
%SpeciesTested
123456789
10 11 12-15 16+
MedicinalApplications
Fig.3.PercentofspeciesscreenedbytheNCIforantitumoractivityaccordingtonumberofmedicinalapplicationsfor
808specieslistedin90of227differentmedicinalapplicationsbyQuisumbing(1951).Thepercentscreenedforeach
numericalcategoryofmedicinalusesofplantsisshowntoincreasefrom45%forspeciesreportedtohavejustone
medicinaluseto99%screenedforthosereportedfor16ormoredifferentmedicinalapplications.
Ontheotherhand,onemightarguethattheuseofplantsformanymedicinal
remediesbyoneormorecukuresshouldconstitutestrongevidencefordiscover-
ingbiologicalactivityAtthespecieslevel,however,culturaldiffusionmightex-
aggerateandmultiplyreports(Watson1983),whereasmedicinalreportsbased
ondisjunctoccurrencesofcloselyrelatedspeciesingeneramayappearmorevalid,
depending,however,onthesizeofthegenusandnumberofmedicinalspecies
reported.Thefollowingsixcasesexemplifyhowfolkloremayappearmonecase
tohavestrongvaliditywhileinotherinstancesappearsinconclusive.
1)Brucea(Simaroubaceae)isasmallpaleotropicalgenusof6specieswith
B.antidyscntericainAfricaandB.javanica(L.)Merr.insoutheastAsiathathave
reportedlybeenusedlortreatingskindiseases,dysenterytapeworm,and
cancer(Burkhill1935;Chopraetal.1956;Dalziel 1937;Hartwell1967-1971;
Quisumbing1951;Watt&Breyer-Brandwijk1962;Webb1948).Anticancerac-
tivityhasbeenidentifiedinbothspeciesandoneother,B.guineensisG.Don,
foundonlyinwesttropicalAfricawithoutanyreporteduse.Theanticancer
compound,bruceantin(Kupchanetal.1973),isolatedfromB.anlidysenterica,
hasundergonepreclinicalstudiesasapotentialdrugforcancerchemotherapy.
Itwastoundtobetoxicinhumanapplication;however,derivativesofrelated