Constituants chimiques à activités antimicrobiennes et antiplasmodiales de deux plantes médicinales camerounaises: Polyalthia oliveri Engl.(Annonaceae) et Canthium multiflorum Schum and Thonn (Rubiaceae)

Abstract

The present work deals with the chemical investigation, chemical transformation as well as antimicrobial, antiplasmodial, and cytotoxic activities of some secondary metabolites isolated from Polyalthia oliveri ENGL. (Annonaceae) and Canthium multiflorum Schum and Thonn (Rubiaceae). Thus, by means of various liquid phase chromatographic technics such as Column Chromatography (CC), High Pressure Liquid Chromatography (HPLC) and Thin Layer Chromatography (TLC) we have isolated: From the ethyl acetate extract of the stem bark of Polyalthia oliveri: 03 new indolosesquiterpens derivatives; N-acétyl 8α-polyveolinone, 8α-polyveolinone and N-acetyl polyveoline; 02 known alkaloids; N-methylurabaine and bidebiline A and 01 known triterpenoid; polycarpol. From the methylene chloride /methanol (1/1) extract of the aerial parts of Canthium multiflorum: 01 new iridoïd; 6-oxo-genipin; 08 known iridoïds; 6-α-hydroxygeniposide, scandoside methyl ester, deacetyl asperulosidique acid, gardenamide, macrophylloside, garjasmine, gardenine and galioside; 02 known triterpenoids; oleanolic acid and quinovic acid; 01 known polyol ; D-mannitol and 01 known phénolic acid ; 4-O-β-D-(6-O- benzoylglucopyranoside) vanilic acid