Prota 11(1): Medicinal plants/Plantes médicinales 1
Flora 47: 534 (1864).
Origin and geographic distribution
Croton membranaceus occurs in Côte d’Ivoire, Ghana and Nigeria.
In Ghana a root extract is taken to treat urinary retention caused by an enlarged prostate. It is also taken to treat measles.
The root bark contains scopoletin and julocrotine, a glutarimide alkaloid. It also contains calcium oxalate crystals.
Monoecious herb or undershrub up to 1(–2) m tall; branches slender, densely stellate hairy. Leaves opposite or alternate, when opposite the two very unequal in size, simple and entire; stipules tiny; petiole 2–6 mm long; blade ovate, 3–7.5 cm × 2–5 cm, base rounded, basal glands absent, apex acuminate, sparsely stellate hairy above, densely stellate hairy beneath. Inflorescence an axillary or terminal raceme c. 5 cm long, few-flowered, with male flowers at end and female flowers at base. Flowers unisexual, 5-merous, regular, white; pedicel short; male flowers with elliptical sepals and obovate petals c. 2 mm long, margin woolly hairy, stamens 10, free; female flowers with narrowly lanceolate sepals c. 4 mm long, petals rudimentary or absent, ovary superior, rounded, densely hairy, 3-celled, styles 3, apex 2-fid. Fruit an ellipsoid, slightly 3-lobed capsule c. 5 mm in diameter, 3-seeded.
Croton comprises about 1200 species and occurs throughout the warmer regions of the world. It is best represented in the Americas; about 65 species occur in continental Africa and about 125 in Madagascar. Another medicinally used Croton with a restricted distribution in West Africa is Croton eluteria (L.) W.Wright (‘cascarilla’), which originates from the Caribbean and northern South America. It was introduced into Nigeria in the 19th century for its use as a tonic and aromatic bitter, which improves digestion. The essential oil of the bark is used in aromatherapy to treat cough, fever, flatulence, nausea and diarrhoea. In the Bahamas the leaves are used to aromatize tobacco. The active compounds of the bark are neoclerodane diterpenoids, such as cascarillins A–I and cascallin.
Croton membranaceus occurs in moist bush vegetation and savanna, at low altitudes.
Genetic resources and breeding
Croton membranaceus has a limited area of distribution and it is apparently uncommon. It is grown in Aburi Botanic Gardens, Ghana.
Some preliminary tests on the activity of Croton membranaceus root extract have been undertaken, but more chemical and pharmacological research needs to be done to evaluate its potential. Measures should be taken to monitor the presence of this apparently uncommon species.
• Antwi, A.S., 1994. Alkaloids of Croton membranaceous. B.Sc. Chemistry degree thesis, Department of Chemistry, Faculty of Science, University of Cape Coast, Cape Coast, Ghana. 29 pp.
• Atakora, A.G., 2004. Pharmacognostic study of the roots of Croton membranaceus (Euphorbiaceae). B.Pharm. degree thesis, Department of Pharmacognosy, Faculty of Pharmacy, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. 31 pp.
• Brown, N.E., Hutchinson, J. & Prain, D., 1909–1913. Euphorbiaceae. In: Thiselton-Dyer, W.T. (Editor). Flora of tropical Africa. Volume 6(1). Lovell Reeve & Co., London, United Kingdom. pp. 441–1020.
• Keay, R.W.J., 1958. Euphorbiaceae. In: Keay, R.W.J. (Editor). Flora of West Tropical Africa. Volume 1, part 2. 2nd Edition. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. pp. 364–423.
• Aboagye, F.A., Sam, G.H., Massiot, G. & Lavaud, C., 2000. Julocrotine, a glutarimide alkaloid from Croton membranaceus. Fitoterapia 71(4): 461–462.
• Hawthorne, W. & Jongkind, C., 2006. Woody plants of western African forests: a guide to the forest trees, shrubs and lianes from Senegal to Ghana. Kew Publishing, Royal Botanic Gardens, Kew, United Kingdom. 1023 pp.
• Lambert, M., Stærk, D., Hansen, S.H. & Jaroszewski, J.W., 2005. HPLC-SPE-NMR hyphenation in natural products research: optimization of analysis of Croton membranaceus extract. Magnetic Resonance in Chemistry 43(9): 771–775.
• Vigor, C., Fabre, N., Fourasté, I. & Moulis, C., 2002. Neoclerodane diterpenoids from Croton eluteria. Journal of Natural Products 65: 1180–1182.
Correct citation of this article:
Schmelzer, G.H., 2007. Croton membranaceus Müll.Arg. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes médicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.