Prota 11(1): Medicinal plants/Plantes mιdicinales 1
Ann. Bot. Roma 13: 405 (1915).
Origin and geographic distribution
Wrightia demartiniana occurs in Ethiopia, Somalia, Kenya and northern Tanzania.
In Kenya ground roots are boiled and the filtrate is drunk to treat kidney problems. Soup made of the fresh roots and chicken is eaten to cure gonorrhoea. Ground twigs in milk are taken as a laxative. Latex is added to goat milk to curdle it to make cheese. The bark is crushed and rubbed on the skin as a perfume. The branches are used to make fire by friction. The plant is eaten by camels and sheep, but is not browsed by goats.
The phytochemistry of Wrightia demartiniana has not been elucidated yet. Other Wrightia species contain triterpenes.
Shrub or small tree up to 5 m tall, with white latex; bark black, branches pale brown or grey, branchlets pubescent. Leaves opposite, simple and entire; stipules very small; petiole 0.52 mm long, shortly hairy; blade narrowly elliptical, elliptical or obovate, 125.5 cm Χ 0.52 cm, base cuneate or decurrent into the petiole, apex rounded to obtuse, short hairy, papery, lateral veins obscure. Inflorescence a terminal cyme on short lateral shoots, few-flowered, 1.52.5 cm long; peduncle 13 mm long, shortly hairy; bracts sepal-like. Flowers bisexual, regular, 5-merous, sweet-scented; pedicel 46 mm long, shortly hairy; sepals fused at base, 1.53 mm long, erect, apex obtuse, shortly hairy outside, inside with 5 scales as long as sepals; corolla white or creamy, tube 57 mm long, gradually narrowed towards the throat, shortly hairy outside, corona 11.5 mm long, shortly lobed, undulate, corolla lobes oblong, 1015 mm long, overlapping to the left, spreading, apex rounded, inside hairy; stamens inserted at corolla mouth, exserted; ovary superior, consisting of 2 free carpels, style 25 mm long, thick, persistent, ending in a pistil head with a globose basal part, a ring in the middle and a 2-lobed apical part. Fruit consisting of 2 narrowly ellipsoid follicles, united at the extreme base, 1230 cm Χ c. 8 mm, tapering into a narrow apex, 2-valved, shortly hairy, grey-green, many-seeded. Seeds spindle-shaped, flattened, 1925 mm long, longitudinally ribbed, pale brown, with a tuft of dirty white hairs 3.54 cm long.
Wrightia occurs in the Old World and comprises about 25 species, of which 2 in continental Africa. The Asian Wrightia arborea (Dennst.) Mabb. is cultivated as an ornamental in Senegal and Kenya. Wrightia natalensis Stapf is a small tree occurring in Zimbabwe, Mozambique, Swaziland and eastern South Africa. In South Africa the ground roots are steeped in water and the pulp is applied to fontanelles of babies to close them. The root is chewed or the root powder is drunk in beer as an aphrodisiac.
Wrightia demartiniana occurs in dry rocky Acacia and Commiphora bushland, at 1001000 m altitude.
Genetic resources and breeding
As Wrightia demartiniana is not uncommon in its distribution area, and not much used, it is probably not threatened by genetic erosion.
Wrightia demartiniana will remain of local importance only, unless promising information on its pharmacological activity becomes available.
Leeuwenberg, A.J.M., 1988. The African species of Wrightia R.Br. In: Leeuwenberg, A.J.M. (Editor). Series of revisions of Apocynaceae 22. Agricultural University Wageningen Papers 875. pp. 3343.
Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.
Omino, E.A. & Kokwaro, J.O., 1993. Ethnobotany of Apocynaceae species in Kenya. Journal of Ethnopharmacology 40: 167180.
Beentje, H.J., 1994. Kenya trees, shrubs and lianas. National Museums of Kenya, Nairobi, Kenya. 722 pp.
Bisset, N.G., 1988. Phytochemistry and uses of Wrightia demartiniana and W. natalensis. In: Leeuwenberg, A.J.M. (Editor). Series of revisions of Apocynaceae 22. Agricultural University Wageningen Papers 875. p. 54.
Leeuwenberg, A.J.M., 2003. Apocynaceae. In: Hedberg, I., Edwards, S. & Sileshi Nemomissa (Editors). Flora of Ethiopia and Eritrea. Volume 4, part 1. Apiaceae to Dipsacaceae. The National Herbarium, Addis Ababa University, Addis Ababa, Ethiopia and Department of Systematic Botany, Uppsala University, Uppsala, Sweden. pp. 8798.
Correct citation of this article:
Schmelzer, G.H., 2006. Wrightia demartiniana Chiov. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes mιdicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.