Prota 11(1): Medicinal plants/Plantes médicinales 1
Prodr. 9: 520 (1845).
Bois de Laurent-Martin (Fr).
Origin and geographic distribution
Tournefortia acuminata is endemic to Réunion.
The leaves of Tournefortia acuminata are considered to have diuretic properties and are traditionally used to treat kidney stones in Réunion.
The presence of alkaloids has been confirmed by general tests on Tournefortia acuminata but otherwise nothing is known of its chemistry. Laboratory tests with leaf extracts of Tournefortia acuminata did not confirm the diuretic properties claimed in folk medicine. Leaf extracts of Tournefortia argentea L.f. have been proven efficient in counteracting poisoning by ciguatoxins (produced by the dinoflagellate Gambierdiscus toxicus and transferred by fish): they counteract the neurocellular effects and have beneficial action on the gastro-intestinal disturbances. Pyrrolizidine alkaloids have been isolated from twigs of Tournefortia argentea. Several phenolic compounds, including salicylic acid and tournefolin A–C, have been isolated from the stems of Tournefortia sarmentosa Lam., a species from tropical Asia that is widely used medicinally.
Shrub or small tree; stem with minute, closely appressed brown or golden hairs or glabrous. Leaves alternate, simple and entire; blade obovate to elliptical, 12–17 cm × 3.5–7 cm, acute at base and at apex, with 10–15 pairs of veins. Inflorescence a terminal, dichotomously branched, scorpioid cyme. Flowers bisexual, regular, 5-merous, sessile; calyx 1.5–2 mm long, sparsely hairy; corolla white, tube 3.5–7 mm long, lobes c. 4 mm wide. Fruit a small, white, globose drupe c. 6 mm in diameter, splitting into two 2-seeded parts.
Tournefortia and related genera are in need of revision. Tournefortia comprises about 100 species, most of them native in America and with about 15 species in the Old World, 2 in mainland Africa and 4 endemic to the Indian Ocean islands.
The widespread Tournefortia argentea L.f. (synonym: Argusia argentea (L.f.) Heine), ‘octopus tree’, ‘veloutier blanc’ or ‘bois tabac’, occurs on coastal beaches from Kenya to Mozambique, the Indian Ocean islands and through Asia to Australia. The leaves are used as a poison antidote in Vietnam and New Caledonia; they are eaten raw as a vegetable and smoked like tobacco.
Tournefortia acuminata is found throughout Réunion, but is nowhere abundant. It tends to flower in the cyclone season (November–April).
Genetic resources and breeding
In Réunion Tournefortia acuminata is considered rare and vulnerable, and in need of protection. The other African Tournefortia species, with the exception of Tournefortia argentea, are uncommon and vulnerable as well.
Almost nothing is known about the phytochemistry and pharmacological properties of the African Tournefortia species. Research into the chemistry and pharmacology is long overdue. However, they are likely to remain of limited importance. Survival of the vulnerable species should be assured by protection of their habitats.
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Correct citation of this article:
Bosch, C.H., 2006. Tournefortia acuminata A.DC. In: Schmelzer, G.H. & Gurib-Fakim, A. (Editors). Prota 11(1): Medicinal plants/Plantes médicinales 1. [CD-Rom]. PROTA, Wageningen, Netherlands.