Tongkat Ali

31 Pages·2016·0.71 MB·English

molecules
Review
Review on a Traditional Herbal Medicine,
Eurycoma longifolia Jack (Tongkat Ali):
Its Traditional Uses, Chemistry, Evidence-Based
Pharmacology and Toxicology
ShaheedUrRehman,KevinChoeandHyeHyunYoo*
InstituteofPharmaceuticalScienceandTechnologyandCollegeofPharmacy,HanyangUniversity,Ansan,
Gyeonggi-do426-791,Korea;[email protected](S.U.R.);[email protected](K.C.)
* Correspondence:[email protected];Tel.:[phone]
AcademicEditor:ChristopherW.K.Lam
Received:28January2016;Accepted:3March2016;Published:10March2016
Abstract: EurycomalongifoliaJack(knownastongkatali),apopulartraditionalherbalmedicine,is
a flowering plant of the family Simaroubaceae, native to Indonesia, Malaysia, Vietnam and also
Cambodia, Myanmar, Laos and Thailand. E. longifolia, is one of the well-known folk medicines
for aphrodisiac effects as well as intermittent fever (malaria) in Asia. Decoctions of E. longifolia
leavesareusedforwashingitches,whileitsfruitsareusedincuringdysentery. Itsbarkismostly
usedasavermifuge,whilethetaprootsareusedtotreathighbloodpressure,andtherootbarkis
used for the treatment of diarrhea and fever. Mostly, the roots extract of E. longifolia are used as
folkmedicineforsexualdysfunction,aging,malaria,cancer,diabetes,anxiety,aches,constipation,
exerciserecovery,fever,increasedenergy,increasedstrength,leukemia,osteoporosis,stress,syphilis
andglandularswelling. Therootsarealsousedasanaphrodisiac,antibiotic,appetitestimulantand
healthsupplement. Theplantisreportedtoberichinvariousclassesofbioactivecompoundssuchas
quassinoids, canthin-6-one alkaloids, β-carboline alkaloids, triterpene tirucallane type, squalene
derivatives and biphenyl neolignan, eurycolactone, laurycolactone, and eurycomalactone, and
bioactive steroids. Among these phytoconstituents, quassinoids account for a major portion of
theE.longifoliarootphytochemicals. AnacutetoxicitystudyhasfoundthattheoralLethalDose50
(LD )ofthealcoholicextractofE.longifoliainmiceisbetween1500–2000mg/kg,whiletheoral
50
LD oftheaqueousextractformismorethan3000mg/kg. Liverandrenalfunctiontestsshowedno
50
adversechangesatnormaldailydoseandchronicuseofE.longifolia. Basedonestablishedliterature
onhealthbenefitsofE.longifolia,itisimportanttofocusattentiononitsmoreactiveconstituents
andtheconstituents’identification,determination,furtherdevelopmentandmostimportantly,the
standardization. Besides the available data, more evidence is required regarding its therapeutic
efficacyandsafety,soitcanbeconsideredarichherbalsourceofnewdrugcandidates. Itisvery
importanttoconservethisvaluablemedicinalplantforthehealthbenefitoffuturegenerations.
Keywords:traditionalherbalmedicine;Eurycomalongifolia;quassinoids;pharmacologicaleffects;safety
Molecules2016,21,331;doi:10.3390/molecules21030331 www.mdpi.com/journal/molecules
Molecules2016,21,331 2of31
1. Introduction
1.1. Traditional,Complementary/AlternativeandHerbalMedicine
1.1.1. TraditionalMedicine
This is also well known as indigenous or folk medicine. According to the World Health
Organization (WHO), traditional medicine is defined as “the sum total of the knowledge, skills,
and practices based on the theories, beliefs, and experiences indigenous to different cultures,
whetherexplicableornot,usedinthemaintenanceofhealthaswellasintheprevention,diagnosis,
improvementortreatmentofphysicalandmentalillness”[1].
1.1.2. Complementary/AlternativeMedicine
The terms “complementary medicine” and/or “alternative medicine” (and sometimes also
“non-conventional”) are used interchangeably with “traditional medicine” in some countries.
Complementary/alternativemedicinereferstoabroadsetofhealthcareandhealth-relatedpractices
thatarenotpartofthatspecificcountry'sowntradition,andarenotconsideredthedominanthealth
caresystem[2].
1.1.3. HerbalMedicine
AccordingtotheWHO,itincludesherbs,herbalpreparations,herbalmaterials,andallfinished
herbalproducts,thatcontainplants,otherplantmaterials,orcombinations,asanactiveingredient[2].
1.1.4. TraditionalUseofHerbalMedicines
Thisreferstothelonghistoricortraditionaluseofherbalbasedmedicines. Theusesofthese
medicinesarewell-establishedandwidelyacknowledgedtheirsafetyandefficacy,aswellasaccepted
bynationalhealthauthorities[2].Traditionallyemployed,indigenousherbalorherb-derivedmedicines
havebeenverypopularfromtimeimmemorial;andtoday,thesemedicineshavecommandedmuch
attentionworldwide,duetotheirnaturaloriginandnutraceuticalpotential[2,3]. TheWorldHealth
Organizationhasestimatedthat80%ofpeopleworldwiderelyonherbalmedicinesforsomepart
oftheirprimaryhealthcareneeds[4]. Whenadoptedoutsideofitstraditionalculture, traditional
medicineisoftencalledcomplementaryandalternativemedicine[1].
Worldwide,manytraditionalmedicinesystems(TMS)areused,includingChineseTraditional
Medicine,IndianAyurvedicMedicine,andthepopularUnaniMedicineofArabcultures. Manyother
indigenoustraditionalmedicinesystemshavealsobeendevelopedinpasthistorybyAfrican,Asian,
Arabic,Pacific,American,andalsosomeothercultures. Thetheoryandapplicationofthesetraditional
medicinesystems,differsignificantlyfromthoseofwell-developedallopathicmedicines[3]. Today,
the increasing demands of use of traditional herbal therapies, more likely based on the good past
experiencesoftheeffectivenessaswellassafetyoftheseherbalmedicines,stillrequirepositiveresearch
evidence,sorecentdevelopmentsinthebiologicalandanalyticalsciences,alongwithinnovations
inproteomicsandgenomicssurelycanplayadominantroleinthevalidationoftraditionallybased
herbalmedicines,tofurtherimprovetheirquality,safetyandefficacywithclinic-basedevidence[5,6].
1.2. EurycomalongifoliaJack—APromisingHerbalMedicine
Thisisawelljustifiedfactthatthetraditionalmedicinesaswellascomplementaryandalternative
medicineshavethewell-establishedroleinourhealth. E.longifoliaJack(TongkatAli)isoneofthe
mostwell-knownherbalfolkmedicinesinSoutheastAsia. Itsrootsaretraditionallyusedformany
disordersanddiseases,inmanycountriesAsia. Besidesthis,recentlyE.longifoliahascontributedgood
roleasacomplementaryandalternativemedicineinherbaltherapies,intheWest.
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1.2.1. Synonyms
Tongkat Ali, Ali’s Umbrella or Malaysia ginseng (Malaysia), Pasak Bumi or Bedara Pahit
(Indonesia),Ian-don(Thailand),andCaybabenh(Vietnam),thonan(Laotian).
1.2.2. Origin
IndigenoustoSouth-EastAsiancountrieslikeMalaysia,Indonesia,andVietnam,someofthe
plant species are also found in certain patches in regions of Cambodia, Myanmar, Laos and in
Thailand[5,7–11].ItisplantedmainlyinMalaysiaforitsmedicinalvalueinordertoconservethewild
plants[12–15].
BesidesEurycomalongifoliaJack,therearethreeotherplantspeciesalsoknownlocallyasTongkat
Ali,whichliterallymeans“Ali’swalkingstick,”whichreferstoitsaphrodisiacproperty. Someauthors
claimitgetsitsname“stick”fromthelongtwistedrootsthatareharvestedfortheirmedicinalvalue.
ThethreeplantspeciesareEntomophthoraapiculata,Polyathiabullata,andGoniothalamussp.[16].
“Malaysianginseng”asitisknowninMalaysia,isalsoregardedasanadaptogen[17],anherbor
herbalcompoundthatassistsincombatingstressanddiseaseandimprovesphysicalstrengthwithout
adverseeffects.
1.2.3. Description
E. longifolia is a tall, slender, shrubby tree, which grows in sandy soil. It belongs to the
Simaroubaceae family. It has compound leaves on branches that can grow up to 1 m long. The
leavesarepinnateinshapeandgreenincolour. Thenumerousleafletsareoppositeorsubopposite,
lanceolatetoovate-lanceolate,5–20cmby1.5–6cm,withsmoothmargins. Flowersaretiny,reddish,
unisexualandaredenselyarranged. Thedrupesareovoidwithadistinctridge,1–2cmby0.5–1.2cm
andtheyturndarkreddishbrownwhenripe[18–20].
1.3. GeneticDiversity
The genetic diversity of E. longifolia is decreasing due to widespread harvesting; thus, single
nucleotidepolymorphismshavebeenusedtostudytheremainingdiversity[21],andmicrosatellite
markershavebeenstudiedastoolsforDNAprofilingandgeneticdiversitystudies[22]. Razietal.,
showedthatinanuncontrolledcultivatedarea,theE.longifoliasamplescouldbecharacterizedbased
ontheircultivar’sorigins. TheyprovedthatidentificationofE.longifoliafromvariouscultivarscan
beobtainedusingPCR-RAPD,withthehelpofsomeanalyticalsoftware. Themethodyieldedhigh
qualityandquantityofDNA.Sixrandomprimers(OPA-3,OPA-4,OPA-13,OPA-18,OPC-5andOPC-6)
werefoundtogivegoodamplificationsofE.longifoliaDNAsamples[23]. Somescientistsareinterested
intheinvitroproductionoftheE.longifoliaplantletsorplanttissuesforsustainableproductionof
active ingredients [24–31]. Ling et al. developed a protocol to optimize protoplast isolation from
callus of E. longifolia [32]. Most recently, Lulu et al., optimized the conditions for the production
of adventitious roots from E. longifolia, in balloon-type bubble bioreactor cultures, suitable for the
large-scalecommercialproductionofitsrootscontaininghighyieldofbioactivecompounds[33].
2. HistoricalorTraditionalUses
E.longifoliaisusedtocurelumbagoandindigestion. Itisusedasapowertonicafterdelivery,and
usefortreatmentoffever,jaundice,cachexia,anddropsy[12,34]. E.longifoliaisoneofthemostpopular
folkmedicinesforitsaphrodisiaceffectsandtreatmentofintermittentfever(malaria)[35]. Decoctions
ofE.longifolialeavesareusedforwashingitches,whileitsfruitsareusedincuringdysentery[12]. Its
barkismostlyusedasavermifuge[12],whilethetaprootsareusedtotreathighbloodpressure,and
therootbarkisusedforthetreatmentofdiarrheaandfever[36]. MostlytherootsextractofE.longifolia
are used as folk medicine for sexual dysfunction, aging, malaria, cancer, diabetes, anxiety, aches,
constipation,exerciserecovery,fever,increasedenergy,increasedstrength,leukemia,osteoporosis,
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stress, syphilis and glandular swelling, as well as it is used as an aphrodisiac, antibiotic, appetite
stimulantandhealthsupplement[36–42].
Traditionally,thewaterdecoctionofE.longifoliarootisconsumed. Nowadays,moreconvenient
formulasareavailable,primarilyadditivesmixedwithteasandcoffees,andover200productsare
availableeitherintheformofrawcruderootpowderorascapsulesmixedwithotherherbsinthe
health-foodmarket[7]. Duetothemanytraditionalandscientificbenefits,therehasbeenademandfor
E.longifoliaproductswithover200E.longifoliaproductsregisteredwiththeNationalPharmaceutical
ControlBureauofMalaysia(NPCB,2016). ItisnowcurrentlysoldasaTraditionalHerbalMedicinein
Malaysia. Approximately21,000kgofE.longifoliaareharvestedbycollectorsperyear,withademand
ofapproximately>54,000kgperyear.
3. ChemicalConstituents
Thewidespectrumofpharmacologicaleffectswascloselyassociatedwithvariousbiologically
active compounds of E. longifolia roots, stem, leaves and even bark. Kuo et al., reported the
isolation of sixty five phenolic compounds from the E. longifolia root [36]. E. longifolia is a
rich source of various classes of bioactive compounds, which includes quassinoids, β-carboline
alkaloids,canthin-6-onealkaloids,triterpene-typetirucallane,squalenederivatives,andeurycolactone,
eurycomalactone, laurycolactone, biphenyl neolignan and bioactive steroids [7,36,42–45]. Among
these, bitter tasting quassinoid phytoconstituents account for a major portion in the E. longifolia
root contents. The quassinoids are a group of nortriterpenoids with dynamic pharmacological
properties [40]. Quassinoids, are even effective at inhibiting cell growth in nanomolar and
subnanomolarconcentrations[41]. Thepresenceoftirucallaneandsqualene-typetriterpenesmightbe
thequassinoids’biologicalprecursors. β-CarbolineandCanthin-6-onealkaloidsformedasmetabolic
by-products are natural amine compounds that repel herbivores and insects [46]. The metabolite
typeandconcentrationinE.longifoliaplantextracts,dependontheprocessingtemperatureaswell
asgeographicalfactors. Forstandardization, itiscrucialtoensuretheconsistencyofthechemical
bioactivecomponents, particularlyfortheefficacyofherbalmedicines[47]. Summarizedhereare
somemajorconstituentsofE.longifoliawiththeirsecondarymetabolites:
Quassinoids, including various types of eurycomanone (pasakbumin-A), eurycomanols,
pasakbumin-B, hydroxyklaineanones, eurycomalactones, eurycomadilactones, eurylactones,
laurycolactones, longilactones, and hydroxyglaucarubol have been isolated from the roots of
E.longifolia[38,39,48–52].
The squalene derivatives include teurilene, eurylene; 14-deacetyleurylene; and longilene
peroxide[53,54].
Thebiphenylneolignansclassincludes;2-hydroxy-3,2,6-trimethoxy-4-(2,3-epoxy-1-hydroxypropyl)
-5-(3-hydroxy-1-propenyl)-biphenyl;twoisomeric2,2-dimethoxy-4-(3-hydroxy-1-propenyl)-4-(1,2,3-
trihydroxypropyl)diphenylethers;and2-hydroxy-3,2-dimethoxy-4-(2,3-epoxy-1-hydroxypropyl)-5-(3-
hydroxy-1-propenyl)biphenyl[55].
Alkaloidsincluded5,9-dimethoxycanthin-6-one;9,10-dimethoxycanthin-6-one,11-hydroxy-10-
methoxycanthin-6-one; 10-hydroxy-9-methoxycanthin-6-one; and 9-methoxy-3-methylcanthin-
5,6-dione[45,56,57].
Major isolated chemical constituents with metabolites from E. longifolia Jack and their
pharmacologicaleffects,arelistedinTable1,whiletheirchemicalstructuresarepresentedinFigure1.
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Table1.MajorisolatedchemicalconstituentswithmetabolitesfromEurycomalongifoliaJackandtheirpharmacologicaleffects.
ChemicalCompoundsIsolated PlantParts PharmacologicalEffects References(Isolation&PharmacologicalEffects)
Increasedtestosteroneproduction
Eurycomanone(C20) Improvedspermatogenesis
13α,21-Dihydroeurycomanone
ExpressionSuppressionoflungcancercelltumormarkers,
13α(21)-Epoxyeurycomanone
prohibitin,annexin1andendoplasmicreticulumprotein28
13β-Methyl,21-dihydroeurycomanone
Roots Cytotoxicityagainsthumanlungcancer(A-549),andhuman [36,39,45,51,58–68]
12-Acetyl-13,21-dihydoeurycomanone
breastcancer(MCF-7)celllines
15-Acetyl-13α(21)-epoxyeurycomanone
AntimalarialagainstP.falciparum
12,15-Diacetyl-13α(21)-epoxyeurycomanone
NF-κBinhibitor
1β,12α,15β-Triacetyleurycomanone
Anti-estrogenicactivity
Eurycomanol(C20)
Eurycomanol-2-O-β-D-glucoside Roots AntimalarialagainstP.falciparum [36,39,48,52,58–60,64,66,67]
13β,18-Dihydroeurycomanol
13β,21-Dihydroxyeurycomanol
5α,14β,15β-Trihydroxyklaineanone
11-Dehydroklaineanone
Cytotoxicityagainsthumanlungcancer(A-549),andhuman
12-epi-11-Dehydroklaineanone
Leaves,Roots breastcancer(MCF-7)celllines [35,36,45,48,51,58,69]
14,15β-Dihydroxyklaineanone
NF-κBinhibitor
15β-Hydroxyklaineanone
15β-Acetyl-14-hydroxyklaineanone
LaurycolactonesAandB(C18) Roots CytotoxicityagainsthumanHT1080 [42,69]
Eurycomalactone(C19)
6α-Hydroxyeurycomalactone
Cytotoxicityagainsthumanlungcancer(A-549),breastcancer
7α-Hydroxyeurycomalactone
(MCF-7)andgastriccancer(MGC-803)celllines
5,6-Dehydroeurycomalactone Roots [36,45,49,51,58,59,61,69,70]
CytotoxicityagainsthumanHT1080cells
Eurycomadilactone(C20) AntimalarialagainstP.falciparum
5-iso-Eurycomadilactone
13-epi-Eurycomadilactone
EurycomalidesAandB(C19) Cytotoxicityagainsthumanlungcancer(A-549),andhuman
EurycomalideC
Roots breastcancer(MCF-7)celllines [36,42,45]
EurycomalideD
NF-κBinhibitor
EurycomalideE
Eurycomaoside Roots ENR [71]
CytotoxicityagainsthumanHT1080
Cytotoxicityagainsthumanlungcancer(A-549),andhuman
Longilactone(C19) breastcancer(MCF-7)celllines
6-Dehydroxylongilactone Leaves,Roots [36,42,45,58,69,72,73]
Compoundspossessanti-tumorpromoting,antischistosomal
11-Dehydroklaineanone
andplasmodicidalactivities
NF-κBinhibitor
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Table1.Cont.
ChemicalCompoundsIsolated PlantParts PharmacologicalEffects References(Isolation&PharmacologicalEffects)
EurycolactoneA(C20)
EurycolactoneB(C18) CytotoxicityagainsthumanHT1080 [42,44,45,51,74]
EurycolactoneD(C18) Roots NF-κBinhibitor
EurycolactonesE,F(C19)
EurylactonesAandB(C18) ENR [51,69,75]
EurylactonesE,FandG(C19)
Canthin-6-onealkaloids
9-Methoxycanthin-6-one
9-Hydroxycanthin-6-one
9-Methoxycanthin-6-one-N-oxide Oxidativeburstinhibitory,andcytotoxicactivity
9-Hydroxycanthin-6-one-N-oxide Cytotoxicityagainsthumanlungcancer(A-549),andhuman
1-Hydroxy-9-methoxycanthin-6-one breastcancer(MCF-7)celllines
5-Hydroxymethyl-9-methoxycanthin-6- AntimalarialagainstP.falciparum
10-Hydroxycanthin-6-one Plant(bark,StemandRoots) Anti-ulceractivity [36,45,62,69,76–81]
10-Hydroxy-9-methoxycanthin-6-one NF-κBinhibitor
10-Hydroxy-11-methoxycanthin-6-one Activecytotoxicityagainsthumancancercelltypes(breast,
11-Hydroxy-10-methoxycanthin-6-one colon,fibrosarcoma,lung,melanoma,KB)andmurine
4,9-Dimethoxycanthin-6-one lymphocyticleukemia(P-388)
5,9-Dimethoxycanthin-6-one
9,10-Dimethoxycanthin-6-one
9-Methoxy-3-methylcanthin-5,6-dione
β-Carbolinealkaloids
7-Hydroxy-β-carboline-1-propionicacid
1-Methoxymethyl-β-carboline AntimalarialagainstP.falciparum
Roots [56,61,76,82]
n-pPentylβ-carboline-1-propionate Anti-inflammatoryeffectviaNF-κBinhibition
β-Cararboline-1-propionicacid
β-7-Methoxycarboline-1-propionicacid
Biphenylneolignans
2-Hydroxy-3,2-dimethoxy-4-(2,3-epoxy-1-hydroxypropyl)
-5-(3-hydroxy-1-propenyl)-biphenyl Stem ENR [47,55]
2-Hydroxy-3,2,6-trimethoxy-4-(2,3-epoxy-1-hydroxypropyl)
-5-(3-hydroxy-1-propenyl)-biphenyl
Squalene-typetriterpenes
Eurylene
Cytotoxicity
14-Deacetyleurylene Stem [54,83,84]
CytotoxicactivityagainstKBcells
Longileneperoxide
Teurilene
Phytosterols
(Campesterol,stigmasterol,sitosterol) Plant ENR [85]
Saponins
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Table1.Cont.
ChemicalCompoundsIsolated PlantParts PharmacologicalEffects References(Isolation&PharmacologicalEffects)
Anti-ulcer
Pasakbumin-A,-B,-C,-D(C20) Roots Cytotoxicityagainsthumanlungcancer(A-549)andhuman [36,50]
breastcancer(MCF-7)celllines
Tirucallane-typetriterpenes
Anti-canceractivityagainstovarianleukemiaandrenal
(Niloticin,dihydroniloticin,piscidinolA,bourjotinoloneA, Stem [69]
celllines
3-episapelinA,melianone,andhispidone)
Tirucallane-typetriterpenoid
Stem ENR [77]
23,24,25-Trihydroxytirucall-7-en-3,6-dione
Oxasqualenoid Stem ENR [77]
Anthraquinonesandanthraquinoneglucosides Roots ENR [78]
Glycoprotein Plant ENR [86]
Incellsuspensioncultures,twocanthin-6-onealkaloids
9-Hydroxycanthin-6-one Plant AntimalarialagainstP.falciparum [76,87–89]
9-Methoxycanthin-6-one
Predominantaminoacids
Plant(Roots) ENR [90]
Alanine,proline,arginine,andserine
A4.3kDabioactivepeptide Roots ENR [91]
Starch(about39%) Roots ENR [92]
Note:ENR=EvidenceNotReported(muchoftheavailableevidenceaboutthepharmacologicaleffectsofEurycomaLongifolia,isrelatedtoitsextracts(mixtures),sotheseeffects
cannotbecorrelatedwithspecificchemicalconstituentsorgroups).
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Figure1.ChemicalstructuresofvariousbiologicalactiveconstituentsfromE.longifolia;(A)7-Methoxy-
beta-carboline-1-propionicacid(C15);(B)9-methoxycanthin-6-one(C15);(C)Laurycolactone(C17);
(D)EurycolactoneB(C18);(E)EurycomalideA(C19);(F)Eurylactone(C19);(G)Longilactone(C19);
(H) Eurycomalactone (C19); (I) Eurycomanone (C20); (J) Eurycomanol (C20); (K) Pasakbumin B
(C20);(L)Hydroxyklaineanone(C20);(M)Biphenyl-neolignan(C21);(N)Quassin(C22,basicringof
quassinoids);(O)Niloticin(C30);and(P)Eurylene(C34).
4. AnalyticalMethods
Besides the major constituents, secondary metabolites are usually present in a small amount.
That’swhy,highsensitivityandhighmassaccuracyisrequiredtoproducereliabledata. Mostly,data
fromIR,UV,MSandX-rayanalysiswasevaluatedfurtherfor1H-and13C-NMRspectralanalysis.
Theseproceduresforidentificationofunknownentity,requirehighpurityaswellashighconcentration
ofextractedcompounds.
Today, mass spectrometry is the most specific and versatile method of detection in liquid
chromatography, especially perfect for the analysis of some multiple components pharmaceutical
andherbalproducts[93,94]. Liquidchromatographywithmassspectrometry(LC-MS)isrecognized
as a most suitable and powerful tool for identification as well as quantification of various herbal
productandtheirconstituents[95–97]. Fromtheplantkingdom,quassinoidsarebitterconstituents
found exclusively in various species of the Simarouboidaea (a subfamily of the Simaroubaceae)
and are biogenetically degraded triterpenes displaying a wide range of physiological properties
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invitro and/or invivo [98,99]. Numerous research reports are available on liquid chromatography
methods for the analysis of quassinoid E. longifolia bio-constituents, using photodiode array or
fluorescence and UV detection. However, none of these methods are sensitive enough to detect
nonchromophoric bioactive constituents, such as eurycomanol present in E. longifolia [57,58,100],
so mass spectrometry is the best option for analysis of all constituents and secondary metabolites
from E. longifolia. Chua et al., used a number of three liquid chromatography mass spectrometry
hybrid systems (QTof, QTrap and TripleTof), to scan for small metabolites and also to detect
the targeted metabolites, such as alkaloids, quassinoids, triterpene and biphenylneolignans from
E. longifolia extracts [47]. Teh et al., developed and optimized a LC-MS method using ESI in a
positive ion mode for bioactive compounds simultaneous determination, from E. longifolia [101].
Recently, liquid chromatography-tandem mass spectrometry method for the simultaneous
determinationofsixmajorquassinoidsofE.longifoliai.e.,eurycomanone,13α(21)-epoxyeurycomanone,
13,21-dihydroeurycomanone,14,15β-dihydroxy-klaineanone,longilactoneandeurycomalactonewas
developed. ByusingaLC-MSmethod,thecontentofthesequassinoidswasmeasuredinindietary
supplementtabletsandcapsules,toconfirmthepurityofE.longifoliaincommercialproducts[102].
ForquickscreeningofsildenafilanaloguesinE.longifoliaproducts,atwo-tierscreeningmethodusing
anearinfrared(NIR)spectraldatabasewasdeveloped. Thismethodhasallowedrapidscreeningon
thetestsamplestoverifytheircontentaslabelleddespitenothavingthespectraofthoseproductsin
thedatabase. Itcouldbeusedforproductidentification,drugscreeningformixedadulterationaswell
asdrugqualitysurveillance,particularlyincaseswherereferencesamplesaredifficulttoobtain[103].
5. Evidenced-BasedPharmacology
5.1. MaleFertilityEnhancementEffect
Infertility is a major clinical problem, which affects the people medically, economically and
psychosocially. Almost, 15% of all couples in the U.S. are infertile, and it is predicted that the
male factor is responsible in many of such cases [104]. Male infertility refers to a male’s inability
to achieve a pregnancy in a fertile female. In humans, this accounts for 40%–50% of infertility
cases[105,106].Infertilityinmalesisamultifactorialdisease,basedonnumerousfactorsincluding
reducedspermatogenesisandalsoproductionofdysfunctionalsperm,whicharethemajorprevalent
underlyingcharacteristicinidiopathicmaleinfertilitycases[107,108]. Onemeta-analysisofsixty-one
studiesworldwidereportedsdownwardtrendinthespermcountandsemenvolumeoverthepast
fiftyyears[109,110].
Mostly,thewater-solubleE.longifoliaextractswerereportedtobeabletoenhancemalefertility
(withregardstohighersemenvolumes,spermatozoacount,andmotility)inrodents[111,112]andin
humantrials[86,113,114].
ThestandardizedextractF2ofE.longifolia(25mg/kgp.o)anditsmajorquassinoids,especially
eurycomanone(250mg/kgp.o)improvedratspermatogenesisbyaffectingthehypothalamic-pituitary-
gonadalaxisandthepotentialefficacymaybeworthyoffurtherinvestigation[111].
Eurycomanone, the major quassinoid in the E. longifolia root extract, significantly increased
testosteroneproductiononadose-dependentmannerat0.1,1.0and10.0µM(p<0.05). Itenhanced
testosteronesteroidogenesisattherattesticularLeydig’scellsbyinhibitingaromataseconversionof
testosteronetooestrogen,andmayalsoinvolveinphosphodiesteraseinhibitionatahighconcentration,
soauthorshavesuggestedthatquassinoidsfromE.longifoliamaybeworthyforfurtherdevelopment
as new phytomedicines for the treatment of testosterone-deficient idiopathic male infertility and
sterility [112]. Also, standardized extracts of E. longifolia Jack containing a high concentration of
quassinoids (20% eurycomanone and 4% of 13α,21-dihydroeurycomanone) may have potential
anti-estrogeniceffects[86].
The quassinoid-containing E. longifolia extract affects male infertility by suppressing α-2-HS
glycoproteinexpression,whichindirectlyincreasesthetestosteronelevelsandinsulinsensitivity. They
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indicatedthatserumα-2-HSglycoproteinwasreducedinratstreatedwithstandardizedE.longifolia
extract, which will provide rational for further investigation in animal models of infertility with
diabetes[113].
A randomized, double-blind, placebo-controlled, parallel group study was conducted to
investigatetheaphrodisiacclinicalevidenceofE.longifoliaextractinmen. Thetotaltwelveweeks’
studyin109-menbetween30-and55-yearsofage,dividedinagroupof300mgofwaterextractof
E.longifolia(Physta®)-treatedandplacebo. TheE.longifoliagroupshowedhigherscoresintheoverall
erectile-function-domain(IIEF,p<0.001),thesexuallibido(14%byweek12),SeminalFluidAnalysis
(SFA)-withspermmotilityat44.4%,andsemen-volumeat18.2%aftertreatment[114].
Chanetal.,statisticallyanalyzedthespermatozoacount,morphology,motility,plasmatestosterone
levelandLeydigcellcountoftheanimalsbyANOVA.Theirresultsshowedthatthespermcountsof
ratsgiventhestandardizedmethanolextractaloneatdosesof50,100and200mg/kgwereincreasedby
78.9%,94.3%and99.2%,respectively,whencomparedwiththatofcontrol(p<0.01)[115].
AngandNgaishowedthatthefractionsofE.longifoliaJack(0.5g/kg)decreasedthehesitation
time. Furthermore,theycausedatransientincreaseinthepercentageofthemaleratsrespondingto
therightchoice;morethan50%ofthemaleratsscored“rightchoice”;usingtheelectricalcopulation
cage[116].
E. longifolia has been shown to elevate serum testosterone and increased muscle strength in
humans. Chenetal.,investigatedtheeffectsofstandardizedwaterextractofE.longifolia(Physta®)ata
doseof400mg/dayfor6weeksontestosterone: epitestosterone(T:E)ratio,liverandrenalfunctions
inmalerecreationalathletesfoundnosignificantdifferencebetweentheresultsofsupplementation
resultsandplacebo[117].
Study on the sexual qualities of middle-aged male rats after dosing with 0.5 g/kg of various
fractionsofE.longifolia,showedthatitenhancedthesexualqualitiesofthemiddle-agedmaleratsby
decreasingtheirhesitationtimeascomparedtocontrols[118].
A randomized, double-blind, study with placebo-controlled was conducted for proprietary
freeze-driedwaterextractofE.longifolia(Physta®)effectsonsexualperformanceandwell-beingin
men. Forthisstudy,menaged40–65yearswerescreenedfor12-week. Resultsshowedthesignificant
improvementsinscoresforthesexualintercourseattemptdiary,erectionhardnessscale,sexualhealth
inventoryofmen,andagingmalesymptomscale(p<0.05forall),concludedthatPhysta®waswell
toleratedandmoreeffectivethanplaceboinenhancingsexualperformanceinhealthyvolunteers[59].
E.longifoliaextractactsasapotentialagenttoincreasespermatogenesisandspermcounts,and
forreversingtheeffectsofestrogeninrats,afterfourteenconsecutivedaysoftreatment[119].
Inotherstudy,Angetal.,showedthatE.longifoliaproducedadose-dependent,recurrentand
significantincreaseintheepisodesofpenilereflexesasevidencedbyincreasesinquickflips,longflips
anderectionsofthetreatedmaleratsduring30minobservationperiod[17].
AccordingtoTambiandImran’sinvestigations,350patientsweregiven200mgoftheE.longifolia
extractdaily,andfollow-upsemenanalyseswereperformedevery3monthsupto9months. These
patientsshowedsignificantimprovementinallsemenparameters,allowingfor11(14.7%)spontaneous
pregnancies[120].
Erasmus et al., treated semen samples with E. longifolia extract (invitro condition), found a
significantdose-dependenttrendsforvitality,totalmotility,acrosomereactionandreactiveoxygen
species-positivespermatozoa;butnodeleteriouseffectsonspermfunctionsattherapeuticallyused
concentrations(<2.5µg¨mL´1)[121].
Anincreaseinspermcount,motilityandviabilityinrats,whentreatedwithaqueousE.longifolia
extract. Nooretal.,investigatedthatE.longifoliacanincreasesexualbehaviorofmaleratsandthe
spermquality;whichwerefoundtobedosedependent[122]. OnestudyindicatesthatE.longifolia
exertsproandrogeniceffectsthatenhancethetestosteronelevel[123].
TheinvivoeffectofaqueousextractofE.longifoliawasinvestigatedonbodyandorganweight
aswellasfunctionalspermparametersintermsofsafetyandefficacyinthemanagementofmale