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Taiwanese scientists isolated 65 biochemical compounds from the roots of Eurycoma longifolia, of which ten exhibited "strong cytotoxicity" towards human lung and breast cancer cell lines.

Eurycoma longifolia (a.k.a. tongkat ali or pasak bumi) is a flowering plant in the family Simaroubaceae, native to Indonesia and Malaysia.


Eurycoma longifolia is a small everred treelet growing to 15 m (49 ft) tall, with spirally arranged, pinnate leaves 2040 cm (8-16 inches) long with 13-41 leaflets. The flowers are dioecious, with male and female flowers on different trees; they are produced in large panicles, each flower with 5-6 very small petals. The fruit is green ripening dark red, 12 cm long and 0.51 cm broad.

Biological effects

A 2010 ethnopharmacological inventory study on Eurycoma longifolia stated: "The plant parts have been traditionally used for its antimalarial, aphrodisiac, anti-diabetic, antimicrobial and anti-pyretic activities..." [2]

Even though there are many other legitimate medical areas of interest in Eurycoma longifolia (as evident from the quote included above), most Southeast Asians consume it for the plant's impact on sexual conduct. Already in 2001, Malaysian scientific researchers opened their peer-reviewed, Medline-archived report on Eurycoma longifolia's effect on lab rats with the statement "that Eurycoma longifolia Jack commonly known as Tongkat Ali has gained notoreity as a symbol of man's ego and strength by the Malaysian men because it increases male virility and sexual prowess during sexual activities."[3]

An article on the website of the scientific journal Nature referred to Eurycoma longifolia as Malaysia's home-grown Viagra and cited "increased sexual desire, enhanced performance and general well-being".[4] This journal article is also indexed on Medline, but without abstract.[5]

Some scientific studies found that it enhances sexual characteristics and performance in rodents.[6][7][8] Other laboratory animal tests have produced positive indications, with one extract having been observed to increase sexual activity in mature rats, including arousal, sniffing, and mounting behavior. In an experiment conducted on male rats, it was found that eurycoma longifolia increases the sperm count and plasma testosterone of the rats.[9]

The antimalarial,[10] antibacterial ,[11] antipyretic, antiulcer, antitumor[12], and cytotoxic properties are well documented. Taiwanese scientists isolated 65 biochemical compounds from the roots of Eurycoma longifolia, of which ten exhibited "strong cytotoxicity" towards human lung and breat cancer cell lines.[13]

Apart from the better-known quassinoids, the same group of scientist also isolated beta-carboline alkaloids, several of which were active against lung and breast cancer cell lines.[14]

Investigating the activity of 24 Eurycoma longifolia quassinoids against cancer cell lines, including lung cancer cells, medical researchers in Japan found that eurycomalactone was as effective against cancer cells as the established anti-cancer drug doxorubicin. [15] The same group of researchers also discovered several new biochemical compounds in Eurycoma longifolia and screened them for cytotoxic properties. They concluded that different fractions were effective against different cancers.[16] [17] Another study confirmed that fractions of Eurycoma longifolia extract induced apoptosis in breast-cancer cells.[18] Eurycoma longifolia has become popular for its alleged testosterone-enhancing properties.[19] It has therefore been included in some herbal supplements for bodybuilders. In one study, Eurycoma longifolia caused increased muscle strength and size when compared to a placebo.[20]

One extract has since been co-patented by the Government of Malaysia and the Massachusetts Institute of Technology.[21] However, the idea that products of nature on which there exists a large body of knowledge among indigenous peoples can be the subject of intellectual property rights, even of national governments, has long been challenged in peer-reviewed law journals.[22]


Fake Eurycoma longifolia products have been pulled off the shelves in several countries but are still sold over the Internet, mostly shipped from the UK. In a medical journal article, published March 2010, it was noted that "estimates place the proportion of counterfeit medications sold over the Internet from 44% to 90%" with remedies for sexual dysfunction accounting for the greatest share. [23] It is therefore recommended that buyers of Eurycoma longifolia request from Internet vendors conclusive information, and proof, on the facilities where a product has been manufactured.

In Malaysia, the common use of Eurycoma longifolia as a food and drink additive, coupled with a wide distribution of products using cheaper synthetic drugs in lieu of Eurycoma longifolia quassinoids, has led to the invention of an electronic tongue to determine the presence and concentration of genuine Eurycoma longifolia in products claiming to contain it.[24]

On the other hand, consumers who lack the sophisticated electronic tongue equipment invented in Malaysia for testing the presence of Eurycoma longifolia, but want more clarity on whether the product they obtained is indeed Eurycoma longifolia or a fake, can use their own tangue to taste the content of capsules for the bitterness of the material. Quassinoids, the biologically active components of Eurycoma longifolia root[25][26][27], are extremly bitter. They are named after quassin, the long-isolated bitter principle of the quassia tree. Quassin is regarded the bitterest substance in nature, 50 times more bitter than quinine.[28] Anything that isn't bitter, and strongly so, cannot contain quassinoids from Eurycoma longifolia .

In the US, the FDA has banned numerous products such as Libidus[29], claiming to use Eurycoma longifolia as principal ingredient, but which instead are concoctions designed around illegal prescription drugs, or even worse, analogues of prescription drugs that have not even been tested for safety in humans, such as acetildenafil[30]. In February 2009, the FDA warned against almost 30 illegal sexual enhancement supplements [31], but the names of these products change quicker than the FDA can investigate them. Libidus, for example, is now sold as Maxidus, still claiming Eurycoma longifolia (tongkat ali) as principal ingredient.[32]

The government of Malaysia has banned numerous fake products which use drugs like sildenafil citrate instead of tongkat ali in their capsules. To avoid being hurt by bad publicity on one product name, those who sell fake tongkat ali from Malaysia have resorted to using many different names for their wares.[33]

The governments of Canada and Singapore have issued warnings against the product XP Tongkat Ali Supreme for containing the prescription drug tadalafil which can be life-threatening in some individuals.[34]

Products claiming various Eurycoma longifolia extract ratios of 1:20, 1:50, 1:100, and 1:200 are sold. Traditionally Eurycoma longifolia is extracted with water and not ethanol. However, the use of selling Eurycoma longifolia extract based on extraction ratio may be confusing and is not easily verifiable.

In expectation of a competitive edge, some manufacturers are claiming standardization of their extract based on specific ingredients. Alleged standards / markers are the glycosaponin content (35-45%) and eurycomanone (>2%). While eurycomanone is one of many quassinoids in Eurycoma longifolia , saponins, known in ethnobotany primarily as fish poison[35][36] played no role in the academic research on the plant. A Medline [37]search for Eurycoma longifolia returns about 70 journal articles, but the term glycosaponin is not found in a single one of them, and the term saponin only once, in a related link, not as subject of that particular scientific investigation.

A large number of Malaysian Eurycoma longifolia products (36 out of 100) have been shown to be contaminated with mercury beyond legally permitted limits [38] .


"Eurycoma longifolia information from NPGS/GRIN".
www.ars-grin.gov. Retrieved 2008-03-14.

Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia

"Tongkat Ali (Eurycoma longifolia Jack): A review on its ethnobotany and pharmacological importance"
Fitoterapia Volume 81, Issue 7, October 2010, Pages 669-679

Ang HH, Cheang HS School of Pharmaceutical Sciences, University Science Malaysia, Minden, 11800, Penang, Malaysia hhang@usm.my http://www.ncbi.nlm.nih.gov/pubmed/11693547
Arch Pharm Res. 2001 Oct;24(5):437-40.

Cyranoski D.
Malaysian researchers bet big on home-grown Viagra.

Cyranoski D.
http://www.ncbi.nlm.nih.gov/pubmed/16145563 "Malaysian researchers bet big on home-grown Viagra"

Ang HH, Ngai TH, Tan TH (2003).
"Effects of Eurycoma longifolia Jack on sexual qualities in middle aged male rats". Phytomedicine 10 (6-7): 5903.
doi:10.1078/094471103322331881. PMID 13678248.

Ang HH, Cheang HS, Yusof AP. (2000).
"Effects of Eurycoma longifolia Jack (Tongkat Ali) on the initiation of sexual performance of inexperienced castrated male rats". Exp Anim 49 (1): 358.
doi:10.1538/expanim.49.35. PMID 10803359.

Ang HH, Lee KL, Kiyoshi M (2004).
"Sexual arousal in sexually sluggish old male rats after oral administration of Eurycoma longifolia Jack". J Basic Clin Physiol Pharmacol 15 (3-4): 3039.
PMID 15803965.

Chan, Kit-Lam; Low, Bin-Seng; Teh, Chin-Hoe; Das, Prashanta K,
"The effect of Eurycoma longifolia on sperm quality of male rats,"
Nat Prod Commun, 2009 Oct, 4(10):1331-6.

Mohd Ridzuan, M A R; Sow, A; Noor Rain, A; Mohd Ilham, A; Zakiah, I, (2007).
"Eurycoma longifolia extract-artemisinin combination: parasitemia suppression of Plasmodium yoelii-infected mice".
Tropical Biomedicine 24 (1): 1118. PMID 17568384.

Farouk, Abd-Elaziem; Benafri, Asma, (2007).
"Antibacterial activity of Eurycoma longifolia Jack. A Malaysian medicinal plant".
Saudi Medical Journal 28 (9): 14224.
PMID 17768473.

Li, Yan; Liang, Fengshan; Jiang, Wei; Yu, Fusheng; Cao, Rihui; Ma, Qinghe; Dai, Xiuyong; Jiang, Jiandong; Wang, Yanchang; Si, Shuyi (2007).
"DH334, a beta-carboline anti-cancer drug, inhibits the CDK activity of budding yeast".
Cancer biology & therapy 6 (8): 11939.

Kuo PC, Damu AG, Lee KH, Wu TS., Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan
"Cytotoxic and antimalarial constituents from the roots of Eurycoma longifolia"

Kuo PC, Shi LS, Damu AG, Su CR, Huang CH, Ke CH, Wu JB, Lin AJ, Bastow KF, Lee KH, Wu TS. (2003).
"Cytotoxic and antimalarial beta-carboline alkaloids from the roots of Eurycoma longifolia". J Nat Prod 66 (10): 13247. doi:10.1021/np030277n.
PMID 14575431.

Miyake K, Li F, Tezuka Y, Awale S, Kadota S. Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
"Cytotoxic activity of quassinoids from Eurycoma longifolia"

Miyake K, Tezuka Y, Awale S, Li F, Kadota S. Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
"Canthin-6-one alkaloids and a tirucallanoid from Eurycoma longifolia and their cytotoxic activity against a human HT-1080 fibrosarcoma cell line"

Miyake K, Tezuka Y, Awale S, Li F, Kadota S. Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
"Quassinoids from Eurycoma longifolia"

Tee TT, & Azimahtol HL. (2005).
"Induction of apoptosis by Eurycoma longifolia jack extracts". Anticancer Res 25 (3B): 220513.
PMID 16158965.

Chan, Kit-Lam; Low, Bin-Seng; Teh, Chin-Hoe; Das, Prashanta K (2009).
"The effect of Eurycoma longifolia on sperm quality of male rats". Nat Prod Commun 4 (10): 13316.
PMID 19911566.

Hamzah S, Yusof A (October 2003).
"The Ergogenic Effects of Eurycoma Longifolia Jack: A Pilot Study". Br. J. Sports Med. 37: 46470.
doi:10.1136/bjsm.37.5.464. - Abstract of study listed as item 007

U.S. Patent 7,132,117
Inventors: T.G. Sambandan, ChoKyun Rha, Azizol Abdul Kadir, Norhaniza Aminudim, Johari Md. Saad. Assignees: Government of Malaysia,
Massachusetts Institute of Technology.

Michael J. Huft (October 1995).
"Indigenous People and Drug Discovery Research: A Question of Intellectual Property Rights". Northwestern University Law Review 89.

G. Jackson, S. Arver, I. Banks, V. J. Stecher
"Counterfeit phosphodiesterase type 5 inhibitors pose significant safety risks"
International Journal of Clinical Practice Volume 64, Issue 4, pages 497504, March 2010

M. Z. Abdullah, A. S.A. Rahman, A. Y.M. Shakaff, A. M. Noor
"Discrimination and classification of Eurycoma longifolia Jack in medicinal foods by means of a DSP-based electronic taste sensor"
doi: 10.1191/0142331204tm0103oa Transactions of the Institute of Measurement and Control March 2004 vol. 26 no. 1 19-39

In vitro anti-tumor promoting and anti-parasitic activities of the quassinoids from Eurycoma longifolia, a medicinal plant in Southeast Asia.


Eurycolactones AC, novel quassinoids from Eurycoma longifolia


New antiulcer quassinoids from Eurycoma longifolia

Scientific Committee on Food Opinion of the Scientific Committee on Food on quassin


FDA Warns Consumers About Dangerous Ingredients in "Dietary Supplements" Promoted for Sexual Enhancement


FDA Warning Letter


Hidden Risks of Erectile Dysfunction "Treatments" Sold Online

This no-follow link to a spam site is included only as evidence and reference that the illegal drug Libidus is now sold as Maxidus,
still with the claim that it is mostly Eurycoma longifolia.

title=Etumax products banned by ministry
| url=http://www.mmail.com.my/content/etumax-products-banned-ministry

Foreign Product Alert - XP Tongkat Ali Supreme

http://www.jstor.org/pss/4107559 Fish-poison plants

C. E. Bradley, Division of Biology, California Institute of Technology

"Arrow and fish poison of the American southwest"

http://www.ncbi.nlm.nih.gov/pubmed/ Pubmed /
Medline home

Ang H, Lee E, Cheang H.
Determination of Mercury by Cold Vapor Atomic Absorption Spectrophotometer in
Tongkat Ali Preparations Obtained in Malaysia.

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Last updated: October 13, 2010