Prota 11(1): Medicinal plants/Plantes mιdicinales 1
Peters, Naturw. Reise Mossambique Vol. 6, Botanik 1: 276 (1861).
Origin and geographic distribution
Strophanthus petersianus occurs in East and southern Africa, from southern Kenya to Zimbabwe, Mozambique and eastern South Africa.
Throughout its distribution area, the seeds of Strophanthus petersianus are used to make arrow poison. In general poison makers do not discriminate between the Strophanthus species growing in their area. Strophanthus petersianus is used by Zulu herbalists in South Africa as a charm against evil.
From the seeds the cardiac glycoside (cardenolide) sarmentocymarin and its aglycone sarmentogenin has been isolated. Panstroside has been found in seeds from Malawi. The whole plant gave a positive test for haemolysis.
Deciduous shrub or liana up to 15 m long, with white or reddish exudate; stem up to 10 cm in diameter; bark pale grey; branches usually glabrous, with corky flattened triangular protuberances up to 2.5 cm high at the nodes. Leaves decussately opposite, simple and entire; stipules absent; petiole 213 mm long; blade elliptical to ovate, 311 cm Χ 1.55 cm, base cuneate to rounded, apex acuminate, glabrous. Inflorescence a terminal dichasial cyme, on long or short branches or in the forks, 14-flowered, usually glabrous; peduncle 06 mm long; bracts linear or narrowly elliptical, 2.511 mm long, deciduous. Flowers bisexual, regular, 5-merous, fragrant; pedicel 17.5 mm long; sepals free, unequal, ovate or narrowly elliptical, 521 mm long, acute; corolla tube 1535 mm long, widening at 2040% of its length into a cup-shaped upper part, at the mouth 1030 mm wide, glabrous outside, short-hairy inside, white turning yellow near the base and purplish near the apex of the tube, yellow and purple-streaked inside, corona lobes narrowly triangular, 615 mm long, white, with a purple line in the middle, corolla lobes ovate, narrowing into slender pendulous tails, lobes including the tail 90205 mm long, undulate, maroon-violet outside, yellow inside; stamens inserted at 612 mm from the base of the corolla tube, included, acumen on anther 14 mm long; ovary half-inferior, 2-celled, style 7.514.5 mm long, ending in a ringlike pistil head surrounding the minute stigma. Fruit composed of 2 ellipsoid follicles 2037 cm Χ 23.5 cm, tapering into an obtuse apex, 2-valved, divergent at an angle of 180°, wall thick and hard, dark brown, glabrous, with lenticels, many-seeded. Seeds almost spindle-shaped, 1018 mm long, densely pubescent, at apex with a long beak up to 12 cm long, glabrous for (20)3565 mm, upper part with long hairs up to 9 cm long.
Strophanthus comprises 38 species, of which 30 occur in continental Africa, 1 in Madagascar and 7 in Asia, from India to South-East Asia. Strophanthus petersianus produces flowers and leaves towards the end of the dry and the beginning of the rainy season. Mature fruits can be found in the dry season.
Strophanthus petersianus occurs in coastal forest and woodland, often on rocky localities, from sea-level up to 1100 m altitude.
Genetic resources and breeding
Strophanthus petersianus is relatively common in East and southern Africa and is not in danger of genetic erosion.
Strophanthus petersianus has so far mainly been used for making arrow poison and this use is declining rapidly. The effects of sarmentocymarin on cell-proliferative diseases are being studied.
Beentje, H.J., 1982. A monograph on Strophanthus DC. (Apocynaceae). Mededelingen Landbouwhogeschool Wageningen 824. Wageningen, Netherlands. 191 pp.
Neuwinger, H.D., 1998. Afrikanische Arzneipflanzen und Jagdgifte. Chemie, Pharmakologie, Toxikologie. 2nd Edition. Wissenschaftliche Verlagsgesellschaft mbH, Stuttgart, Germany. 960 pp.
Watt, J.M. & Breyer-Brandwijk, M.G., 1962. The medicinal and poisonous plants of southern and eastern Africa. 2nd Edition. E. and S. Livingstone, London, United Kingdom. 1457 pp.
Chandra Singh, U., 2004. Liposomal formulations of digitalis glycosides for treating cell-proliferative and other diseases. U.S. Patent Application. 21 pp.
Githens, T.S., 1948. Drug plants of Africa. African Handbooks: 8. University of Pennsylvania Press, Lancaster Press, Lancaster, United States. 125 pp.
Omino, E.A., 2002. Apocynaceae (part 1). In: Beentje, H.J. & Ghazanfar, S.A. (Editors). Flora of Tropical East Africa. A.A. Balkema, Rotterdam, Netherlands. 116 pp.
Correct citation of this article:
de Ruijter, A., 2006. Strophanthus petersianus Klotzsch. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes mιdicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.
obtained from B. Wursten