Eurycoma longifolia (commonly called tongkat ali or pasak bumi) is a flowering plant in the family Simaroubaceae, native to Indonesia, Malaysia, and, to a lesser extent, Thailand, Vietnam, and Laos. It is also known under the names penawar pahit, penawar bias, bedara merah, bedara putih, lempedu pahit, payong ali, tongkat baginda, muntah bumi, petala bumi (all the above Malay); bidara laut (Indonesian); babi kurus (Javanese); cây bá bệnh (Vietnamese) and tho nan (Laotian). Many of the common names refer to the plant's medicinal use and extreme bitterness. "Penawar pahit" translates simply as "bitter charm" or "bitter medicine". Older literature, such as a 1953 article in the Journal of Ecology, may cite only "penawar pahit" as the plant's common Malay name.
Eurycoma longifolia is a small, evergreen tree growing to 15 m (49 ft) tall with spirally arranged, pinnate leaves 20–40 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, 1–2 cm long and 0.5–1 cm broad.
A 2010 ethnopharmacological inventory study on Eurycoma longifolia stated: "The plant parts have been traditionally used for its antimalarial, aphrodisiac, anti-diabetic, antimicrobial and antipyretic activities…"
In an experiment conducted on male rats, it was found that Eurycoma longifolia increases sperm count. The authors also reported that the plasma testosterone level of Eurycoma longifolia extract treated rats "was significantly increased when compared with that of the control and infertile animals." Another group of scientists confirmed that Eurycoma longifolia has the capacity to "reverse the inhibitory effects of estrogen on testosterone production and spermatogenesis."
According to WebMD, while evidence suggest that one specific Eurycoma longifolia supplement might have some role in boosting sperm quality, there is insufficient evidence to rate it for any other claimed use including treatments for erectile dysfunction, low sex drive, cancer, malaria and tuberculosis.
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.
One extract has been co-patented by the government of Malaysia and the Massachusetts Institute of Technology. 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.
Quassinoids, the biologically active components of Eurycoma longifolia root, are extremely 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. 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, 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. In February 2009, the FDA warned against almost 30 illegal sexual enhancement supplements, 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.
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.
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.
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 however Eurycoma longifolia that is of the higher strength ratios tends to be darker in colour resembling a very dark brown at the 1:200 ratio.
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 played no role in the academic research on the plant.
- "Eurycoma longifolia information from NPGS/GRIN". www.ars-grin.gov. Retrieved 2008-03-14.
- Medicinal Plants, International Technology Center, United Nations International Development Organisation, UNIDO, Trieste, Italy
- Free Indonesian and Malay dictionary search
- Wyatt-Smith, J. (August 1953). "The Vegetation of Jarak Island, Straits of Malacca". Journal of Ecology 41 (2): 207–225. doi:10.2307/2257036. JSTOR 2257036.
- Bhat, R; Karim, AA (2010). "Tongkat Ali (Eurycoma longifolia Jack): a review on its ethnobotany and pharmacological importance". Fitoterapia 81 (7): 669–79. doi:10.1016/j.fitote.2010.04.006. PMID 20434529.
- Chan, KL; Low, BS; Teh, CH; Das, PK (2009). "The effect of Eurycoma longifolia on sperm quality of male rats". Natural product communications 4 (10): 1331–6. PMID 19911566.
- Wahab, NA; Mokhtar, NM; Halim, WN; Das, S (2010). "The Effect of Eurycoma Longifolia Jack on Spermatogenesis in Estrogen-Treated Rats". Clinics 65 (1): 93–8. doi:10.1590/S1807-59322010000100014. PMC 2815289. PMID 20126351.
- "Eurycoma longifolia". WebMD. Retrieved 17 October 2013.
- Abdullah, M.Z.; Rahman, A.S.A.; Shakaff, A.Y.M.; Noor, A.M. (2004). "Discrimination and classification of Eurycoma longifolia Jack in medicinal foods by means of a DSP-based electronic taste sensor". Transactions of the Institute of Measurement and Control 26: 19. doi:10.1191/0142331204tm0103oa.
- U.S. Patent 7,132,117Inventors: T.G. Sambandan, ChoKyun Rha, Azizol Abdul Kadir, Norhaniza Aminudim, Johari Md. Saad. Assignees: Government of Malaysia, Massachusetts Institute of Technology.
- Huft, Michael J. (October 1995). "Indigenous People and Drug Discovery Research: A Question of Intellectual Property Rights". Northwestern University Law Review 89.
- Jiwajinda, S; Santisopasri, V; Murakami, A; Sugiyama, H; Gasquet, M; Riad, E; Balansard, G; Ohigashi, H (2002). "In vitro anti-tumor promoting and anti-parasitic activities of the quassinoids from Eurycoma longifolia, a medicinal plant in Southeast Asia". Journal of Ethnopharmacology 82 (1): 55–8. doi:10.1016/S0378-8741(02)00160-5. PMID 12169407.
- Ang, H (2000). "Eurycolactones A–C, novel quassinoids from Eurycoma longifolia". Tetrahedron Letters 41 (35): 6849. doi:10.1016/S0040-4039(00)01159-X.
- Tada, H; Yasuda, F; Otani, K; Doteuchi, M; Ishihara, Y; Shiro, M (1991). "Nouveaux quassinoïdes antiulcéreux à partir d'Eurycoma longifolia". European Journal of Medicinal Chemistry 26 (3): 345. doi:10.1016/0223-5234(91)90069-Y.
- Scientific Committee on Food Opinion of the Scientific Committee on Food on quassin SCF/CS/FLAV/FLAVOUR/29 Final
- 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.
- "Etumax products banned by ministry".
- Foreign Product Alert – XP Tongkat Ali Supreme
- Howes, F. N. (1930). "Fish-Poison Plants". Bulletin of Miscellaneous Information 1930 (4): 129–53. doi:10.2307/4107559. JSTOR 4107559.
- Bradley, C. E. (October 1956). "Yerba de la fleche—Arrow and fish poison of the American southwest". Economic Botany 10 (4): 362–6. doi:10.1007/BF02859766.
- Ang, Hooi-Hoon; Lee, Ee-Lin; Cheang, Hui-Seong (2004). "Determination of Mercury by Cold Vapor Atomic Absorption Spectrophotometer in Tongkat Ali Preparations Obtained in Malaysia". International Journal of Toxicology 23 (1): 65–71. doi:10.1080/10915810490269654. PMID 15162849.