In vitro cytotoxicity of norviburtinal and isopinnatal from Kigelia pinnata against cancer cell lines

Crude dichloromethane extracts of Kigelia pinnata stem bark and fruit showe d cytotoxic activity in vitro against cultured melanoma and other cancer ce ll lines using the Sulphorhodamine B assay, which was used for bioassay-gui ded fractionation. Thin layer chromatography (TLC) examination of the most active fractions of both stem bark and fruits showed the presence of the sa me major components which were found to be norviburtinal and beta -sitoster ol. Norviburtinal was found to be the most active compound but had little s electivity for melanoma cell lines whilst isopinnatal also showed some cyto toxic: activity. beta -Sitosterol was found to be comparatively inactive. H PLC analysis of the crude extract showed that the amount of norviburtinal p resent in the plant material did not account for all of the activity of the total extracts.