Brucea spp.

2015

Botanical Aspects

Brucea (Simaroubaceae) is a widely distributed genus occurring in tropical Africa and tropical Asia. Brucea species are very bitter monoecius or dioecius shrubs or small trees ranging from 0.3-10 m in height. Willis (1966) grouped Brucea into ten species; however, in the revision for the Flora Malesiana Nooteboom (1962) accepts only six species, consequently, some species’ names which have appeared in the chemical literature are now accepted as synonyms of other species. The major species are:

1. B. javanica (L.) Merr., known as Kho-sam, Ya-Tan-Tzu, and Macassar kernels. It is distributed from Sri-Lanka through SE Asia to China and Taiwan, and throughout Malaysia to N Australia. The species has been introduced into Fiji and Micronesia. Among the synonyms of B. javanica are B. sumatrana Roxb., B. sumatrensis Speng., B. gracilis DC, B. glabrata Decne., and B. amarissima Desv. and Merr..

2. B. mollis Wall., commonly known as makamara or suga. Ranges from east of the Himalayas, through Burma, Thailand, Laos, Cambodia, and Hainan to Malaysia, and also throughout the Philippines. Synonyms for this species include B. luzoniensis Vidal, B. membranacea Merr., B. macrobotrys Merr., B. stenophylla Merr., and B. accuminata L..

3. B. antidysenterica Mill., is found in upper Guinea, the Cameroons, and Ethiopia. Synonyms for this species include B.ferruginea L’Her., B. tenuifolia Engl. and B. salutaris A. Chev..

4. B. quineensis Don. (syn B. macrophylla Oliv.), found in West Africa, Upper Guinea, and Sierra Leone.

Uses in Traditional Medicine

Certain species of the Simaroubaceae are used in traditional medicine throughout the tropical world to combat various diseases, including amebiasis, cancer, and malaria. Of the Brucea species, B. javanica and B. antidysenterica have well established uses in traditional medicine. B. javanica and B. antidysenterica are used for the treatment of numerous conditions, including diarrhea, dysentery, fever, and asthma. In many instances, a paste is prepared from leaves and young twigs for use in the treatment of leprosy and tumorous growths. Extracts prepared from the roots have been shown to be active against Plasmodium gallinaceum in chicks, and hence there is the possibility for the extraction of constituents with antimalarial activity. Extracts of Brucea have also been shown to have significant insecticidal activity. To confirm these traditional uses, extracts of these plants are found to be active against 1210 lymphoid leukemia, solid murine tumors, Levis lung carcinoma, and B-16 melanocarcinoma. Extracts also show potent amebicide activity, and more recently have been shown to be active against Plasmodium falciparum in vitro.

Summary

Brucea contains two groups of biologically active constituents which are of interest medicinally. However, in cell culture only the canthin-6-one alkaloids are produced. Unpublished results from experiments with Ailanthus (Simaroubaceae) in the author’s laboratory suggest that biosynthesis of quassinoids takes place in the aerial part of the plant, since the leaves of young seedlings have relatively high levels of quassinoids. These constituents were not found in root cultures, but shoot cultures produced quassinoids if particular hormone regimes were used. It would seem, therefore, that for quassinoid production a degree of differentiation is required, and this may be linked with the ability to carry out photosynthesis.

Selections from the book: “Medicinal and Aromatic Plants VI”, 1994.