Full original manuscript
Secondary metabolites from Desmodium ramosissimum G. Don (Fabaceae) and their radical scavenging properties
Raymonde A. Dzatie Djoumbissie1, Didy H. Sonfack Fozeng1, Yves M. Mba Nguekeu1, Pierre Tane1, Hiroyuki Morita2, Maurice D. Awouafack1*
1Natural Products Chemistry Research Unit, Department of Chemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon
2Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194, Japan
This work was designed to carry out the phytochemical study and the radical scavenging screening of the MeOH extract from the whole plant of Desmodium ramosissimum used in traditional medicine for the treatment of malaria, fever, diarrhea, lung disorders and venereal diseases. The crude extract was subjected to silica gel open column chromatography (CC) follow by repeated silica gel CC purification and / or Sephadex LH-20 to afford nine compounds, D-pinitol (1), mixture of β-sitosterol (2) and stigmasterol (3), β-sitosterol-3-O-β-D-glucopyranoside (4), glyceryl-1-tetracosanoate (5), lutein (6), kaempferol (7), catechin (8) and vitexin (9). The structures of these compounds were identified after analysis of their NMR and MS data and comparison with the literature. The crude extract, fractions III, IV and V displayed constituents possessing radical scavenging activities using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) bioautography while vitexin (9), and catechin (8) showed activity among the isolated compounds.
Key words: Desmodium ramosissimum; constituents; Radical scavenging, Vitexin; Kaempferol.