Abstract

The dried pulverised stem bark of Euphorbia poissoni, family Euphorbiaceae, was exhaustively and successively extracted with diethylether, chloroform and methanol using Soxhlet extractor. The methanol extract was fractionated into two: alkaloid extract and alkaloid free methanol extract. The extracts were screened for antimicrobial activity. The methanol and alkaloid free methanol extracts both showed antibacterial activity. The alkaloid free methanol extract was fractionated using preparative TLC (coated with silica gel 245 HF), developed with benzene:ethylacetate (9:l) to obtain 8 fractions. The fractions were screened for antibacterial activity and fractions, F1, F3, F4 and F5 showed activity. The chemical classes of the fractions and extracts were identified. Major constituents of the plant are alkaloids, tannins, saponins, glycosides, flavonoids and carbohydrates. Steroidal glycosides are the antibacterial agent of the plant.