Prota 11(1): Medicinal plants/Plantes médicinales 1
Fl. aegypt.-arab.: 47 (1775).
2n = 24
Solanum dubium Fresen. (1833), Solanum thruppii C.H.Wright (1894).
Origin and geographic distribution
Solanum coagulans occurs in Sudan, Eritrea, Ethiopia, Somalia, Kenya, Uganda and Tanzania. It is also found in Egypt, Yemen and Saudi Arabia. Records for other countries, e.g. China, probably refer to other species of Solanum.
In Kenya the boiled roots of Solanum coagulans are taken to avoid a miscarriage. Roots are chewed by expectant mothers who experience abnormal pain. The dry seeds are powdered and applied to wounds as an antiseptic. In Sudan the whole plant and fruits are pulped and applied to wounds and skin tumours as a dressing. The seeds are taken in Ethiopia as a purgative. The fruits are used for tanning and for coagulating milk. The plants are browsed by cattle, goats, sheep, donkeys and camels.
Erect or spreading perennial herb up to 70 cm tall, young parts covered with stellate hairs; stems with many straight yellow prickles, rarely without. Leaves alternate, variable, simple; stipules absent; petiole 1–6 cm long, with many prickles; blade ovate-lanceolate, 1–10 cm × 1–5 cm, base unequally truncate or slightly cordate, apex rounded, entire or lobed, with rounded lobes. Inflorescence an axillary 6–10-flowered raceme-like cyme. Flowers bisexual, regular, 5-merous; pedicel 1–1.5 cm long; calyx persistent, lobes lanceolate, c. 5 mm long, with many prickles; corolla stellate, 1–2 cm in diameter, pale blue-violet, lobes spreading or reflexed; stamens inserted on corolla throat, unequal, 4 anthers c. 5 mm long, 1 up to 8 mm long, opening by terminal pores; ovary superior, globose, style slightly longer than stamens. Fruit a globose berry c. 1 cm in diameter, yellow, enclosed in enlarged, prickly calyx, many-seeded. Seeds ovoid, compressed, shiny black. Seedling with epigeal germination.
Solanum comprises about 1000 species and has a cosmopolitan distribution, except in boreal, alpine and aquatic habitats. About 110 species are found in tropical Africa. The principal centre of diversity is located in Central and South America, with secondary centres in Africa and Australia. Solanum has been subdivided into 7 subgenera and numerous sections and series; Solanum coagulans belongs to subgenus Leptostemonum. Two other East African species from this subgenus are used medicinally.
Solanum mauense Bitter is only known from Kenya west of the Rift Valley. The Maasai people drink a decoction of the roots as a cure for malaria and chest pain. It is also applied as a cure for anthrax in both humans and livestock. Boiled berries are eaten to cure pneumonia.
Solanum richardii Dunal is a very variable species distributed from DR Congo to East and southern Africa and the Indian Ocean Islands. In Tanzania a root decoction is drunk as a cure for gonorrhoea and as an anti-emetic.
Solanum coagulans occurs in roadsides, waste places and in Acacia- Commiphora bushland up to of 1800 m altitude.
In Sudan Solanum coagulans is an important reservoir of the tomato yellow leaf curl virus (TYLCV), an important viral disease in tomato and Capsicum peppers.
Genetic resources and breeding
Solanum coagulans is widely distributed in ruderal habitats and not threatened by genetic erosion.
As no chemical and pharmacological analyses of Solanum coagulans have been done, meaningful predictions about its prospects cannot be made. The different local medicinal uses are interesting though and warrant research.
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Correct citation of this article:
Bosch, C.H., 2008. Solanum coagulans Forssk. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes médicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.