Gomphocarpus semilunatus (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Medicinal
Fibre

Gomphocarpus semilunatus A.Rich

distribution in Africa (wild)

Protologue: Tent. fl. abyss. 2: 39 (1851).

Family: Asclepiadaceae (APG: Apocynaceae)

Synonyms

• Asclepias semilunata (A.Rich.) N.E.Br. (1902).

Origin and geographic distribution

Gomphocarpus semilunatus is distributed from Nigeria eastward to Ethiopia and from there southward through East Africa to southern DR Congo, Zambia and Angola.

Uses

Fibre from the inner bark of Gomphocarpus semilunatus is used for making fishing nets. After processing, it can be spun with cotton, and it is used to make snares and waistbands. The seed floss is used for stuffing in Uganda.

In traditional medicine in Rwanda a decoction of the whole plant is taken for the treatment of malaria, fever and madness and an extract of the aerial parts is drunk as an aphrodisiac. In Burundi a leaf infusion or juice from the leaves is drunk as an emetic and a leaf decoction is used as wash to serve as a tonic for pregnant women. In Kivu (DR Congo) the whole plant is made into a paste that is rubbed on rheumatic limbs. In Kenya a warm decoction from the roots is drunk to expel intestinal worms and leaves are used as a cure for fever, congested nose and epilepsy. In Uganda the bark is chewed or root preparations are taken to end vomiting, and the whole plant is eaten with groundnut-paste as a cure for hypertension. Drops from crushed leaves are instilled in the nose as a cure for migraine. In veterinary medicine a leaf infusion is instilled to induce uterus contractions in cows.

Properties

The bast fibre strands are 1–1.5 m long, white to pale brown, lustrous and fairly strong. They are considered suitable for coarse textiles. The fibre strands are easily broken down (‘cottonized’) into the ultimate fibres, which have about the same length and width as cotton but lack a natural twist, which might cause trouble in spinning with machinery designed for cotton.

Description

Shrubby perennial herb, 1–2.5 m tall, stems stout, erect, frequently unbranched, densely hairy with spreading white hairs in the upper part, woody at base, with taproot. Leaves opposite or in whorls of 4, simple and entire; petiole 2–6 mm long; blade linear to narrowly linear-lanceolate, 8–12 cm × 0.5–1.5 cm, base cuneate or truncate, apex acute or attenuate, sparsely hairy with soft white hairs particularly on midrib and margins. Inflorescence an extra-axillary, nodding umbel, 5–9-flowered; peduncle 1–4 cm long; bracts deciduous. Flowers bisexual, regular, 5-merous; pedicel 1.5–2 cm long; sepals lanceolate, 5–9 mm long, attenuate; corolla reflexed, white or pink, lobes ovate, 7–9 mm × 4–5 mm, subacute; corona lobes attached c. 1 mm above base of staminal column, laterally compressed, 3 mm × 2.5–3 mm, shorter than the column; anthers with c. 2 mm long wings; ovary superior, carpels 2, free, stigma head flat. Fruit a pair of upright follicles, each follicle subglobose, 7 cm × 5 cm, not beaked, inflated, balloon-like, with filiform processes c. 1 cm long, many-seeded. Seeds ovate with one convex and one concave face, c. 3.5 mm × c. 1.5 mm, warted, hairs c. 3 cm long.

Other botanical information

Gomphocarpus comprises about 20 species and is distributed in tropical Africa and Peninsular Arabia.

Gomphocarpus physocarpus

Gomphocarpus physocarpus E.Mey. is native to Mozambique, Botswana, South Africa and Swaziland. It can be distinguished from Gomphocarpus semilunatus by a much shorter calyx and by the shape of the corona. It has been introduced elsewhere and is found in seasonally dry and disturbed areas of Kenya, Uganda, Tanzania and Zambia. In several Indian Ocean islands an introduced Gomphocarpus species, probably Gomphocarpus physocarpus, is used medicinally. In Australia the species hybridizes with Gomphocarpus fruticosus (L.) W.Aiton and hybridization is probably taking place in East Africa as well. In South Africa the powdered leaves are sniffed as a cure for headache, tuberculosis and as an emetic. The latex is applied to warts. The fibre use that has been reported for the species should be attributed to Gomphocarpus semilunatus.

Ecology

Gomphocarpus semilunatus occurs at 300–2600 m altitude in seasonally flooded grasslands and waste places, frequently in large numbers.

Management

In Rwanda in the 1950s the stems of plants collected from the wild yielded 0.7% fibre after 10 days of retting. Gomphocarpus semilunatus has been cultivated in East Africa, where it proved very susceptible to insect pests. Fibre yields in East Africa have been estimated at 280–400 kg/ha.

Genetic resources

Gomphocarpus semilunatus is widespread and not heavily exploited so no threats are foreseen.

Prospects

The properties of the fibre produced by Gomphocarpus semilunatus is such that it could be used to produce soft fabrics. As a first step to verify the feasibility of commercial exploitation, research into domestication and management are needed.

Major references

• Burkill, H.M., 1985. The useful plants of West Tropical Africa. 2nd Edition. Volume 1, Families A–D. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 960 pp.

• Goulding, E., 1937. Textile fibres of vegetable origin: forty years of investigation at the Imperial Institute. Bulletin of the Imperial Institute (London, United Kingdom) 35: 27–56.

• Goyder, D.J. & Nicholas, A., 2001. A revision of Gomphocarpus R.Br. (Apocynaceae: Asclepiadeae). Kew Bulletin 56(4): 769–836.

• Greenway, P.J., 1950. Vegetable fibres and flosses in East Africa. The East African Agricultural Journal 15(3): 146–153.

• Lejeune, J.B.H., 1953. Contribution à l'étude des plantes à fibres, à Rubona. Bulletin Agricole du Congo Belge 44: 743–772.

Other references

• Chagnon, M., 1984. Inventaire pharmacologique général des plantes médicinales Rwandaises. Journal of Ethnopharmacology 12: 239–251.

• Chifundera, K., 2001. Contribution to the inventory of medicinal plants from the Bushi area, South Kivu Province, Democratic Republic of Congo. Fitoterapia 72: 351–368.

• Fowler, D.G., 2007. Zambian plants: their vernacular names and uses. Kew Publishing, Kew, Richmond, United Kingdom. 298 pp.

• Geissler, P.W., Harris, S.A., Prince, R.J., Olsen, A., Achieng’ Odhiambo, R., Oketch-Rabah, H., Madiega, P.A., Andersen, A. & Mølgaard, P., 2002. Medicinal plants used by Luo mothers and children in Bondo district, Kenya. Journal of Ethnopharmacology 83: 39–54.

• Hamill, F.A., Apio, S., Mubiru, N.K., Bukenya-Ziraba, R., Mosango, M., Maganyi, O.W. & Soejarto, D.D., 2003. Traditional herbal drugs of southern Uganda, 2: literature analysis and antimicrobial assays. Journal of Ethnopharmacology 84: 57–78.

• Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.

• Peyre de Fabrègues, B. & Lebrun, J.-P., 1976. Catalogue des plantes vasculaires du Niger. Etude Botanique 3. Institut d'Elèvage et de Médecine Vétérinaire des Pays Tropicaux. Paris, France. 433 pp.

• Tabuti, J.R.S., Lye, K.A. & Dhillion, S.S., 2003. Traditional herbal drugs of Bulamogi, Uganda: plants, use and administration. Journal of Ethnopharmacology 88: 19–44.

• Vlietinck, A.J., van Hoof, L., Totté, J., Lasure, A., Vanden Berghe, D.A., Rwangabo, P.C. & Mvukiyumwami, J., 1995. Screening of hundred Rwandese medicinal plants for antimicrobial and antiviral properties. Journal of Ethnopharmacology 46: 31–47.

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., 2011. Gomphocarpus semilunatus A.Rich. In: Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 23 December 2024.

• See the Prota4U database.