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12(1): Medicinal and poisonous plants 1

Eurycoma Jack

Mal. Misc. 2: 45 (1822).

SIMAROUBACEAE

x = unknown

Major species Eurycoma apiculata A.W. Bennett, Eurycoma longifolia Jack.

Brunei: langsia siam, tungat ali, pasak bumi. Indonesia: pasak bumi (general), bidara laut, beseng (Sumatra). Malaysia: bedara merah, bedara putih, tongkat ali (Peninsular). Cambodia: antong sar, antoung sar. Laos: tho nan. Thailand: hae phan chan (northern), plaalai phuenk (central), phiak (peninsular). Vietnam: c[aa]y b[as] b[eej]nh.

Eurycoma is confined to tropical South-East Asia and consists of 3 species, with several subspecies. In the Malesian region 2 species are present: a widespread, rather variable species (Eurycoma longifolia), occurring from Burma (Myanmar) trough Indo-China and Thailand, to Peninsular Malaysia, Sumatra, Borneo and the Philippines; and Eurycoma apiculata, which is confined to Peninsular Malaysia and Sumatra.

Where Eurycoma apiculata and Eurycoma longifolia occur sympatrically, the uses are the same for both, and no actual distinction is made. The roots, in particular the bark, are used as a febrifuge, and also as a tonic after childbirth. In Malaysia pounded roots are applied externally as a poultice to treat headache, and also on wounds, ulcers and syphilitic sores. A decoction of the leaves is also sometimes used as a febrifuge. An infusion of the root bark of Eurycoma longifolia is used to treat stomach-ache and fever by the Kenyah Dayak in Borneo. In Kalimantan, Banjarese men drink a decoction of the root as an aphrodisiac, in peninsular Thailand it is used as a traditional remedy against malaria. 'Babi kurus' is the vernacular name used in Java for the imported drug.
In Vietnam Eurycoma longifolia is reputed to cure a variety of diseases ('c[aa]y b[as] b[eej]nh' means the plant for hundred diseases). The bark is prescribed against indigestion, fever and lumbago, the fruits against dysentery. A decoction of the leaves is used as a wash to treat itch. In Cambodia, the root is employed as a vermifuge and as an antidote for intoxication, including drunkenness. A large enough dose of the bitter constituents will provoke vomiting, thereby acting as an antidote for poisoning. Furthermore, roots are used against malaria, as an antipyretic, anti-inflammatory and diaphoretic. The fruits are used against dysentery.

No statistics are available on the production and trade of Eurycoma. Some interinsular trade seems to exist.

Antimalarial activities have been reported from Eurycoma. A semi-purified extract of the powdered root (mainly consisting of the quassinoids 13'BETA',18-dihydroeurycomanol, eurycomanol-2-O-'BETA'-glucopyranoside, eurycomanol and eurycomanone) was evaluated in vitro using 6 chloroquine-resistant Plasmodium falciparum isolates. Results indicated complete inhibitions at 1.25-5 µg/ml extract after 3 days post-treatment, and at 0.62 µg/ml and 0.31 µg/ml after 4 and 6 days post-treatment, respectively. Subsequently, the purified compounds performed well in an in vitro test with 9 Plasmodium falciparum isolates from patients infected with chloroquine-resistant malaria. Eurycomanol, eurycomanol-2-O-'BETA'-glucopyranoside and 13'BETA',18-dihydroeurycomanol possessed antimalarial activities with IC₅₀ values of 1.231-4.899 µM, 0.389-3.498 µM and 0.504-2.343 µM, respectively, compared with 0.323--0.774 µM for chloroquine. Furthermore, the quassinoids eurycomanone, eurycomalactone, 6-hydroxy-5,6-dehydroeurycomalactone and 7-methoxy-'BETA'-carboline-1-propionic acid (a 'BETA'-carboline alkaloid), all isolated from the roots, also demonstrated significant antimalarial activity in vitro.
In general, several constituents isolated from Eurycoma longifolia possess cytotoxic activity. Quassinoids (eurycomalactone, 6'ALFA'-hydroxyeurycomalactone, 5,6-dehydroeurycomalactone, longilactone, 14,15'BETA'-dihydroxyklaineanone, 11-dehydroklaineanone) and tirucallane-type triterpenes (niloticin, dihydroniloticin, piscidinol, boujotinolone A, 3-episapelin A, melianone, hispidone) isolated from the wood have shown potent cytotoxicity against P388 and KB cell lines in vitro. Cathin-6-one alkaloids (biosynthetically derived from the aminoacid tryptophan) were isolated from the root. 9-Methoxy-canthin-6-one, 9-methoxy-canthin-6-one-N-oxide, 9-hydroxy-canthin-6-one and 9-hydroxy-canthin-6-one-N-oxide were active against a panel of human and murine cancer cell lines in vitro: breast, colon, fibrosarcoma, lung, melanoma, KB and P388. Though several other cathin-6-one alkaloids (9,10-dimethoxy-, 10-hydroxy-9-methoxy-, 11-hydroxy-10-methoxy- and 5,9-dihydroxy-cathin-6-one and 9-methoxy-3-methyl-cathin-5,6-dione) are known to be present in the wood and bark, their cytotoxic effects have not been evaluated. Finally, the quassinoid eurycomanone is active against the cell lines mentioned above (except for P388) but, in addition, has significant activity against the KB-V1 (a cell line derived from KB that is resistant to several drugs).
A bioassay study of the trunk root without the root bark of Eurycoma longifolia led to the isolation of four quassinoids pasakbumin-A, -B, -C and -D. Both pasakbumin A (= eurycomanone) and pasakbumin B exhibited potent anti-ulcer activity on stomach ulcers in vivo in the rat, induced by indomethacin as well as by stress.
The effects of Eurycoma longifolia were studied in male rats. Doses of 200-800 mg/kg body weight twice daily for 10 days prior to the test intensified the orientation activities towards receptive females, supporting the aphrodisiac property of the plant.

Strychnos species are used for the same purpose as Eurycoma; they are also called 'bidara laut' in Indonesia.

Small trees or rarely shrubs up to 10 m tall, monoecious or dioecious, branches rather thick with large leaf scars. Leaves alternate, imparipinnate, usually multijugate, crowded at the tip of the branches; leaflets opposite or subopposite, slightly oblique, ovate-lanceolate to obovate-lanceolate, (nearly) sessile, with a conspicuous articulation at base, midrib slightly prominent on the upper surface, prominent beneath, secondary veins straight, ending in an intramarginal looped vein. Inflorescence an axillary panicle, mostly large and lax, puberulous. Flowers bisexual or unisexual, male flower always with a sterile pistil, female flower always with rather large but sterile stamens; calyx small, 5(-6)-lobed, lobes ovate to triangular, acute or blunt, longer than the tube; petals 5(-6), induplicate-valvate in bud, lanceolate or ovate to ovate-oblong; stamens 5(-6), alternating with petals, filaments narrowing to the top, alternating with 5(-6) small, entire, emarginate or cleft staminodes, sometimes a second row of staminodes present, stamens and staminodes sometimes connate with the petals; disk inconspicuous; carpels 5(-6), free, styles attached adaxially near the top and mutually connate or coherent, stigma peltate, 5(-6)-lobed, 1 ovule per carpel. Fruit consisting of up to 5 ellipsoid or ovoid drupes on a stalk of about 3 mm, with very thin exocarp, fleshy mesocarp and hard endocarp. Seeds exalbuminous, with 2 planoconvex cotyledons and a short plumule.

Eurycoma can be found flowering and fruiting all year round, sometimes at an early age. Pollination is probably by insects, and the fleshy fruits are probably dispersed by birds.

Eurycoma is closely related to Quassia, another Simaroubaceae genus, containing similar bitter principles and also used medicinally in South-East Asia. Eurycoma is most often encountered as an unbranched treelet with an umbrella-like rosette of leaves. However, larger specimens with upright branches (see habit drawing) are also found but appear to be increasingly scarce in easily accessible areas.

Eurycoma is a common understorey plant occurring from beach forest to lower montane forest. Eurycoma longifolia rarely occurs up to 1000 m altitude; Eurycoma apiculata occurs from sea-level to about 1200 m altitude, being more common at higher elevations. Eurycoma longifolia shows a preference for acidic, leached, well-drained soils. Both Eurycoma species can be found in primary and secondary vegetation.

It is assumed that Eurycoma can be propagated by seed.

Stem sections of Eurycoma longifolia cultured in Murashige and Skoog medium gave highest callus production when supplemented with 2.0 mg/l naphthalene acetic acid and 0.1 mg/l benzyladenine. Optimum growth of callus was obtained on medium with pH 6.0, adjusted before autoclaving. Cultures grown at 35°C produced the highest amount of biomass. At this temperature, light intensity of 610 lux was adequate and gave the highest callus yield. Callus growth was best at a photoperiod of 24 hours. The callus produced was yellowish, soft and loose. Successful production of plant biomass is the first necessary step towards the establishment of cell cultures for the in vitro production of secondary metabolites.

In general, Eurycoma spp. are collected from the wild or seedlings are transplanted from the forest to the home garden.

The small Eurycoma trees are usually simply uprooted, and the roots are collected and traded. Collecting only bark or leaves involves slightly less destructive harvesting methods.

After harvesting, the roots, bark and leaves of Eurycoma are simply sold in the market. In the Kerayan area in East Kalimantan, the roots are sometimes modelled into cups and filled with water. After some time the water has taken up bitter constituents, and is drunk as a tonic.

There are no known germplasm collections of Eurycoma. As Eurycoma species occur in both primary and secondary forest and are in general common in their areas of distribution, the risk of genetic erosion seems limited. However, as collecting is primarily from the wild and the plants are often destroyed during collection, overexploitation can become a serious risk, especially in easily accessible areas.

The demonstrated antimalarial properties of Eurycoma against chloroquine-resistant Plasmodium falciparum strains deserves further attention. Given the increasing problem of the resistance to antimalarial agents, the development of alternative medicaments is of great importance to keep malaria under control. The crude extract of Eurycoma should be used with caution because of its toxic effect. Further research on the cytotoxic and anti-ulcer effects of isolated compounds seems desirable as well.

Ang, H.H., Chan, K.L. & Mak, J.W., 1995. In vitro antimalarial activity of quassinoids from Eurycoma longifolia against Malaysian chloroquine-resistant Plasmodium falciparum isolates. Planta Medica 61(2): 177-178.
Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. 2nd edition. Vol. 1. Ministry of Agriculture and Co-operatives, Kuala Lumpur, Malaysia. pp. 1000-1002.
Darise, M., Kohda, H., Mizutani, K. & Tanaka, O., 1982. Eurycomanone and eurycomanol, quassinoids from the roots of Eurycoma longifolia. Phytochemistry 21(8): 2091-2093.
Itokawa, H., Kishi, E., Morita, H. & Takeya, K., 1992. Cytotoxic quassinoids and tirucallane-type triterpenes from the woods of Eurycoma longifolia. Chemical and Pharmaceutical Bulletin 40(4): 1053-1055.
Kardono, L.B.S., Angerhofer, C.K., Tsauri, S., Padmawinata, K., Pezzuto, J.M. & Kinghorn, A.D., 1991. Cytotoxic and antimalarial constituents of the roots of Eurycoma longifolia. Journal of Natural Products (Lloydia) 54(5): 1360-1367.
Mitsunaga, K., Koike, K., Tanaka, T., Ohkawa, Y., Kobayashi, Y., Sawaguchi, T. & Ohmoto, T., 1994. Canthin-6-one alkaloids from Eurycoma longifolia. Phytochemistry 35(3): 799-802.
Nguyen Van Duong, 1993. Medicinal plants of Vietnam, Cambodia and Laos. Mekong Printing, Santa Ana, California, United States. pp. 393-394.
Nooteboom, H.P., 1972. Simaroubaceae. In: van Steenis C.G.G.J. (General editor): Flora Malesiana. Series 1, Vol. 6. Wolters Noordhoff, Groningen, the Netherlands. pp. 203-206.
Singaram, N. & Teo, C.K.H., 1994. Factors affecting the biomass production of tongkat Ali (Eurycoma longifolia). Malaysian Applied Biology 22(2): 197-203.
Tada, H., Yasuda, F., Otani, K., Doteuchi, M., Ishihara, Y. & Shiro, M., 1991. New anti-ulcer quassinoids from Eurycoma longifolia. European Journal of Medicinal Chemistry 26(3): 345-350.

Tahan Uji

Eurycoma apiculata
Eurycoma longifolia

Uji, T., 1999. Eurycoma Jack. In: de Padua, L.S., Bunyapraphatsara, N. and Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 12(1): Medicinal and poisonous plants 1. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea

The following species in this genus are important in this commodity group and are treated separatedly in this database:
Eurycoma apiculata
Eurycoma longifolia