Anti-Tubercular Glycolipids from the leaves of Sterculia setigera Del. (Sterculiaceae)
Ibrahim T Babalola, Umar M Umar, Esther A Adelakun
Natural products form one avenue in the search for new anti-tubercular agents with many groups undertaken screening of natural products as the preliminary step to finding new lead compounds. The anti-TB activity of ethno pharmacologically used Sterculia setigera leave was investigated by bioactivity-guided fractionation against virulent strains of Mycobacterium tuberculosis (H37Rv (ATCC27294)) in-vitro, using the Alamar Blue Assay. Repeated purifications of the active fractions using combination of normal and reverse phase chromatography led to the isolation of a fraction with an interesting anti-TB activity (minimum inhibitory concentration of 15.13 µg/ ml). Preliminary spectroscopic studies shows that the most active fraction is a mixture of isomeric glycolipids based on evidence obtained from 1H, 13C nmr spectra. Effort is currently ongoing to separate the mixture for complete individual structure elucidation. This preliminary report is evident to the fact that glycolipids are the anti-mycobacterial agents in S. setigera leaves. This is the first report on the occurrence of biologically active glycolipids from S. setigera leaves.