Protabase Record

Prota 11(1): Medicinal plants/Plantes médicinales 1
Record display

Strophanthus courmontii Sacleux ex Franch.

Protologue
Journ. Bot. (Morot) 7: 300 (1893).
Family
Apocynaceae
Vernacular names
Kia ya mamba, mubongwena, mbuba, mtobwe (Sw).
Origin and geographic distribution
Strophanthus courmontii occurs in east and south-eastern Africa, from southern Kenya through Tanzania, Malawi and eastern Zambia to Zimbabwe and Mozambique.
Uses
In Tanzania a root decoction is drunk to treat rheumatism and also as an aphrodisiac. The seeds of Strophanthus courmontii are used to make ordeal poison and arrow poison. Such poisoned arrows are still used in north-eastern Tanzania to kill animals that are damaging crops. In Malawi, Zimbabwe and southern Mozambique Strophanthus courmontii is used for making arrow poison as are several other Strophanthus species. The wood is used for making walking sticks.
Properties
From unripe seeds various cardiac glycosides (cardenolides) have been isolated, i.e. panstroside and sarmentocymarin, based on the aglycone sarmentogenin, and sarveroside, based on the aglycone sarverogenin. From ripe seeds the glycosides intermedioside, panstroside, sarmentocymarin and sarveroside were isolated. These glycosides are all highly toxic.
Botany
Deciduous liana up to 22 m long or less often a shrub up to 4 m tall, with white latex; stem up to 10 cm in diameter, with corky ridges to 5 cm × 2 cm; branches dark grey to reddish brown, with compressed corky triangles at the nodes, later growing into ridges. Leaves decussately opposite, simple and entire; stipules absent; petiole 3–11 mm long; blade elliptical to ovate or obovate, 2–14 cm × 2.5–6.5 cm, base rounded to cuneate, apex acute to acuminate, thinly papery, glabrous. Inflorescence a terminal dichasial cyme, on long or short branches or in the forks, almost sessile, 1–3-flowered; bracts ovate or narrowly ovate, 1.5–4 mm long, sometimes deciduous. Flowers bisexual, regular, 5-merous, fragrant; pedicel 1–7.5 mm long; sepals free, almost equal, ovate, 3–10 mm long, acute or apiculate, often with pink margins; corolla tube 22–43 mm long, widening at 15–35% of its length into a cup-shaped upper part, at the mouth 17–35 mm wide, hairy inside, white turning yellow near the base and red turning purple near the apex, inside yellow with purple streaks, corona lobes subulate with a wide base, 2–6 mm long, apex obtuse, fleshy, yellow turning purple via red, corolla lobes ovate, 20–57 mm × 10–27 mm, gradually narrowing into the acute apex, white turning yellow, with a violet band on the right margin; stamens inserted at 6–12 mm from the base of the corolla tube, included, anthers acuminate; ovary half-inferior, 2-celled, style 8.5–16 mm long, ending in a ringlike pistil head surrounding the minute stigma. Fruit consisting of 2 ellipsoid follicles 12–26 cm × 3–4.5 cm, with obtuse apex, 2-valved, divergent at 160–200°, wall thick and hard, glabrous, grey- or purplish black, many-seeded. Seeds spindle-shaped, slightly flattened, 10–15 mm long, densely hairy, at the apex with a long beak up to 8.5 cm long, glabrous in lower half, upper half with long hairs, up to 7 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 courmontii flowers towards the end of the dry season while leafless, and to a lesser extent during the rainy season. Mature fruits are present towards the end of the rainy season.
Ecology
Strophanthus courmontii occurs in gallery forest or riverine thickets, less often in forest away from rivers, from sea-level up to 1400 m altitude.
Genetic resources and breeding
Strophanthus courmontii is rather widespread in eastern and southern Africa and not in danger of genetic erosion.
Prospects
Strophanthus courmontii has so far mainly been used for making arrow poison, a use which is declining rapidly. Although it contains glycosides, its medicinal use will be limited and restricted to its area of distribution unless further studies reveal new possibilities.
Major references
• Beentje, H.J., 1982. A monograph on Strophanthus DC. (Apocynaceae). Mededelingen Landbouwhogeschool Wageningen 82–4. Wageningen, Netherlands. 191 pp.
• Neuwinger, H.D., 1998. Afrikanische Arzneipflanzen und Jagdgifte. Chemie, Pharmakologie, Toxikologie. 2nd Edition. Wissenschaftliche Verlagsgesellschaft mbH, Stuttgart, Germany. 960 pp.
• Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 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.
Other references
• Githens, T.S., 1948. Drug plants of Africa. African Handbooks: 8. University of Pennsylvania Press, Lancaster Press, Lancaster, United States. 125 pp.
• Haerdi, F., 1964. Die Eingeborenen-Heilpflanzen des Ulanga-Distriktes Tanganjikas (Ostafrika). In: Haerdi, F., Kerharo, J. & Adam, J.G. (Editors). Afrikanische Heilpflanzen / Plantes médicinales africaines. Acta Tropica Supplementum 8: 1–278.
• McKenzie, A.G., 2002. The rise and fall of strophanthin. International Congress Series 1242: 95–100.
• 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.
Author(s)

•	A. de Ruijter PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Editors

•	G.H. Schmelzer PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
•	A. Gurib-Fakim Faculty of Science, University of Mauritius, Réduit, Mauritius

Associate editors

•	C.H. Bosch PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
•	M.S.J. Simmonds Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, United Kingdom
•	R. Arroo Leicester School of Pharmacy, Natural Products Research, De Montfort University, The Gateway, Leicester LE1 9BH, United Kingdom
•	A. de Ruijter PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

General editors

•	R.H.M.J. Lemmens PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
•	L.P.A. Oyen PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Correct citation of this article:
de Ruijter, A., 2006. Strophanthus courmontii Sacleux ex Franch. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes médicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.