Investigation of Grewia bicolor Juss

Grewia bicolor is a small tree, parts of which are used in Sudanese traditional medicine for treating pustulent skin lesions, internally on indication of a delayed afterbirth and sometimes as a tranquilizer. A phytochemical investigation of Grewia bicolor gave the following results: the petroleum ether extract afforded beta-sitosterol and beta-sitosterol- and triterpene esters, and the triterpenes lupeol and betulin. The methanol extract afforded: beta-sitosterol-glucoside and three alkaloids, harman, 6-methoxyharman and 6-hydroxyharman. The latter is the main alkaloid. The methanol extract shows activity against gram-positive and gram-negative organisms and causes a strong contraction of the isolated rat uterus which can be blocked by methysergide.