Solenostemon monostachyus (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Vegetable
Medicinal
Food security

Solenostemon monostachyus (P.Beauv.) Briq.

Protologue: Engl. & Prantl, Nat. Pflanzenfam. IV, 3a: 359 (1897).

Family: Lamiaceae (Labiatae)

Chromosome number: 2n = 14, 26, 28

Synonyms

Solenostemon ocymoides Schumach. (1827).

Origin and geographic distribution

Solenostemon monostachyus occurs from Senegal to Chad, Central African Republic, DR Congo and Angola.

Uses

The leaves are eaten as a potherb, and the plant has been grown for this purpose. Solenostemon monostachyus has numerous medicinal uses. The leaf sap is considered sedative and stomachic and is applied internally to treat colic, convulsions, fever, headache and cough, especially in children, and externally against eyesight troubles and aphthae. Moreover, leaves are used to treat dysmenorrhoea, haematuria, female sterility, rheumatism, foot infections and snakebites. The roots are used to treat onchocerciasis (river-blindness, craw-craw). The plant has many ritual uses, especially related to pregnancy.

Properties

Fresh leaves contain per 100 g edible portion: water 82.0 g, energy 230 kJ (55 kcal), protein 4.3 g, fat 0.9 g, carbohydrate 10.4 g, fibre 1.9 g, Ca 437 mg, P 109 mg (Leung, W.-T.W., Busson, F. & Jardin, C., 1968).

A test with mice in Nigeria supported the use of Solenostemon monostachyus leaves to treat convulsions in children. The ethanolic leaf extract contains an anticonvulsant principle which depresses the central nervous system. The leaf essential oil contains β-pinene (13%), oct-1-en-3-ol (12.5%), β-caryophyllene (7%), octan-3-ol (7%) and (E,E)-α-farnesene (6%) as the major constituents.

Botany

Annual or perennial, slightly succulent, aromatic herb up to 100 cm tall, branched; stem erect or decumbent, 4-angled, shortly pubescent. Leaves opposite, simple; stipules absent; petiole 1.5–4 cm long; blade ovate, 5–9 cm × 3–6 cm, cuneate at base, obtuse to acute at apex, margin crenate, puberulous and gland-dotted below, distinctly veined. Inflorescence a terminal and slender false spike up to 50 cm long, consisting of compact, sessile or shortly stalked dichasia. Flowers bisexual, zygomorphic; pedicel up to 3 mm long; calyx up to 4.5 mm long, upper tooth ovate, 2 lateral teeth shorter, 2 lower teeth almost completely or completely fused; corolla (5–)9–15 mm long, pubescent, pale bluish purple, with curved tube, 2-lipped, upper lip erect, short, lower lip boat-shaped; stamens 4, curved within the lower corolla lip; ovary superior, 4-celled, style 2-fid. Fruit consisting of 4 orbicular nutlets c. 1 mm in diameter.

Solenostemon comprises some dozens of species and occurs in Africa and Asia. It is sometimes included in Plectranthus. Plectranthus in the strict sense differs in its calyx, of which the lower teeth are united at the base only, whereas the lateral teeth are more or less equal to the lower.

Solenostemon monostachyus is variable and has been divided into 4 subspecies, but intermediate specimens occur.

Ecology

Solenostemon monostachyus occurs in a range of habitats. It can be found as an annual weed in anthropogenic habitats, but also as a perennial herb or even subshrub in rocky savanna.

Genetic resources

Solenostemon monostachyus is widespread in West and Central Africa and common in many regions, and consequently not liable to genetic erosion.

Prospects

Solenostemon monostachyus will probably remain a minor vegetable. More research on its pharmacological properties seems justified in view of its common application in traditional medicine.

Major references

• Berhaut, J., 1975. Flore illustrée du Sénégal. Dicotylédones. Volume 4. Ficoidées à Légumineuses. Gouvernement du Sénégal, Ministère du Développement Rural et de l’Hydraulique, Direction des Eaux et Forêts, Dakar, Senegal. 625 pp.

• Burkill, H.M., 1995. The useful plants of West Tropical Africa. 2nd Edition. Volume 3, Families J–L. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 857 pp.

• Leung, W.-T.W., Busson, F. & Jardin, C., 1968. Food composition table for use in Africa. FAO, Rome, Italy. 306 pp.

• Morton, J.K., 1962. Cytotaxonomic studies on the West African Labiatae. Journal of the Linnean Society - Botany 58(372): 231–283.

• Oden-Onu, U., 1996. Some pharmacological properties: Solenostemon monostachyus. Journal of Herbs, Spices and Medicinal Plants 4(2): 3–7.

Other references

• Busson, F., 1965. Plantes alimentaires de l’ouest Africain: étude botanique, biologique et chimique. Leconte, Marseille, France. 568 pp.

• Mve-Mba, C.E., Menut, C., Lamaty, G., Zollo, P.H.A., Tchoumbougnang, F. & Bessiere, J.M., 1994. Aromatic plants of tropical central Africa. Part XIX. Volatile components from leaves of two Lamiaceae from Cameroon: Leucas deflexa Hook. and Solenostemon monostachyus (P. Beauv.) Briq. Flavour and Fragrance Journal 9(6): 315–317.

Author(s)

• R.H.M.J. Lemmens

PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

Correct citation of this article

Lemmens, R.H.M.J., 2004. Solenostemon monostachyus (P.Beauv.) Briq. [Internet] Record from PROTA4U. Grubben, G.J.H. & Denton, O.A. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.

Accessed 6 March 2025.

• See the Prota4U database.