ISOLATION, CHARACTERIZATION AND RADICAL SCAVENGING SCREENING OF LIGNANS AND ALKALOIDS FROM CALONCOBA GLAUCA (FLACOURTIACEAE)

Caloncoba glauca, a plant from Central Africa (Cameroun, Gabon), it's used for healing skin diseases. The aim of this work is to carry out the phytochemical study of this plant as well as to evaluate the free-radical scavenging activity of its constituents. Repeated silica gel column chromatography followed by Sephadex LH-20 were used to isolate four compounds and their structures were elucidated using spectroscopic analysis, and comparison with published data. The free-radical scavenging assay on a microplate using DPPH was carried out to evaluate the antioxidant activity of the samples. These spectroscopic data allowed us to identify a lignan (sesamin), an alkaloid (dictamine) and a triterpene (lupeol). Lignans and alkaloids have been isolated for the first time from this plant species. The antiradical activity has been highlighted by the use of bio autographic method and disclosed to DDPH. As results, the ethyl acetate extract, sesamin and dictamine revealed antiradical activity. This work reveals the antioxidant activity of sesamin and dictamine. We are currently identifying other compounds and investigating cytotoxicity and other pharmacological activities with the anticancerous potential.