Erythrophleum couminga (PROTA)
Introduction |
Erythrophleum couminga Baill.
- Protologue: Adansonia 10: 105 (1871).
- Family: Caesalpiniaceae (Leguminosae - Caesalpinioideae).
Origin and geographic distribution
Erythrophleum couminga is endemic to Madagascar and restricted to a part of the west coast of about 400 km long and extending 30–40 km inland.
Uses
The powdered bark of Erythrophleum couminga is used in minute doses as a purgative and laxative. In former days, it was used as an ordeal poison. The branches are used as fence posts but the wood is hardly used otherwise.
Properties
The leaves of Erythrophleum couminga are toxic to cattle, but bark and flowers are even more poisonous. The odour of the flowers is said to cause violent headaches and to kill birds. The alkaloid content of the bark is 0.3–0.5%. The bark contains several complex diterpenoid alkaloids, which are esters of tricyclic diterpene acids, with as main components alkaloids of the dimethylaminoethylester type, e.g. coumingine. The alkaloids have a stimulant effect on the heart like the cardiac glycosides of Digitalis, but the effect is very short-lasting. Coumingine has similar effects as cassaine and cassaidine, which are major components in other Erythrophleum species. They have strong anaesthetic and diuretic effects, and increase contractions of the intestine and uterus. Apart from an increase of heart contraction in systole, the alkaloids also demonstrated an increase in diastole. In addition, coumingine caused depressive effects. Coumingine produced severe and long-lasting diarrhoea when given orally. In higher doses, the bark extract is an extremely strong, rapid-acting cardiac poison, in warm-blooded animals causing shortness of breath, seizures and cardiac arrest in a few minutes.
The wood is hard and durable and is resistant to decay.
Description
Small to medium-sized deciduous tree up to 20 m tall; bark rough, fissured; young twigs thinly pubescent, soon glabrescent. Leaves alternate, bipinnately compound with 2–4 pairs of pinnae; stipules triangular, c. 1 mm long, soon falling; petiole 2–6 cm long, rachis up to 20 cm long; leaflets alternate, 8–12 per pinna, ovate, up to 6 cm × 3.5 cm, base rounded, apex shortly acuminate. Inflorescence an axillary panicle consisting of spike-like racemes up to 10 cm long; peduncle hairy. Flowers bisexual, regular, 5-merous, whitish yellow; pedicel c. 1 mm long, hairy; calyx with tube c. 2 mm long, lobes triangular, 1–1.5 mm long; petals oblong to obovate, up to 3 mm long; stamens 10, free, 6–8 mm long; ovary superior, densely woolly hairy, 1-celled, stigma small, cup-shaped. Fruit a flat, straight or slightly curved, dehiscent pod 20–25 cm × c. 5 cm, apex rounded or obtuse, woody, pendulous, (2–)4–8-seeded. Seeds disk-like to oblong or triangular, flattened, 18–23 mm × 17–20 mm × 6–8 mm.
Other botanical information
Erythrophleum comprises about 10 species, 4 or 5 of which occur in continental Africa, 1 in Madagascar, 3 in eastern Asia, and 1 in Australia. The genus is one of the few Caesalpiniaceae reported to contain alkaloids. Erythrophleum couminga resembles the African mainland species Erythrophleum suaveolens (Guill. & Perr.) Brenan but has larger, more robust pods and seeds and is apparently more poisonous. Erythrophleum couminga flowers in the period July–October.
Ecology
Erythrophleum couminga occurs in deciduous woodland on sandy soils near sea-level and in wooded grassland in association with palms. It is resistant to annual grassland fires.
Genetic resources
Erythrophleum couminga is restricted to a small area, but quite common. The limited use indicates that it is not subject to threats of genetic erosion or extinction.
Prospects
Erythrophleum couminga is likely to remain little used.
Major references
- du Puy, D.J., Labat, J.N., Rabevohitra, R., Villiers, J.-F., Bosser, J. & Moat, J., 2002. The Leguminosae of Madagascar. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 750 pp.
- Hegnauer, R. & Hegnauer, M., 1996. Chemotaxonomie der Pflanzen. Band 11b-1. Birkhäuser Verlag, Basel, Switzerland. 500 pp.
- Rasoanaivo, P., Petitjean, A. & Conan, J.Y., 1993. Toxic and poisonous plants of Madagascar: an ethnopharmacological survey. Fitoterapia 64: 117–129.
- Schatz, G.E., 2001. Generic tree flora of Madagascar. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 477 pp.
Other references
- Cronlund, A. & Oguakwa, J.U., 1975. Alkaloids from the bark of Erythrophleum couminga. Acta Pharmaceutica Suecica 12(5-6): 467–478.
- Hegnauer, R. & Hegnauer, M., 1994. Chemotaxonomie der Pflanzen. Band 11a. Birkhäuser Verlag, Basel, Switzerland. 529 pp.
- Oguakwa, J.U. & Cronlund, A., 1976. A new alkaloid from Erythrophleum couminga. Lloydia 39(4): 248.
- Hegnauer, R. & Hegnauer, M., 1994. Chemotaxonomie der Pflanzen. Band 11a. Birkhäuser Verlag, Basel, Switzerland. 529 pp.
Author(s)
- C.H. Bosch, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
Correct citation of this article
Bosch, C.H., 2006. Erythrophleum couminga Baill. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 1 April 2025.
- See the Prota4U database.