Identification of sakurasosaponin as a cytotoxic principle from Jacquinia flammea

The crude ethanolic extract of leaves, stem-bark and roots of J. flammea were tested for their cytotoxic effect against two mammalian cell lines (HeLa and RAW 264.7) and four bacterial species (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa). When tested at the concentration of 100 microg/mL, the root extract showed the highest cytotoxic activity against mammalian cells followed by the stem-bark extract while the leaves extract did not show significant activity. No antibacterial activity was detected for all extracts when tested up to 500 microg/disc in the disc diffusion assay. The cytotoxic root extract was subjected to fractionation using solvents of ascending polarity: petroleum ether, chloroform, ethylacetate, butanol and water. The water fraction which showed cytotoxic activity was further subjected to routine bioassay-guided fraction to lead to the isolation of sakurasosaponin as the active principle. The recorded IC50 value for sakurasosaponin was 11.3 +/- 1.52 and 3.8 +/- 0.25 microM (n=3) against HeLa and RAW 264.7 respectively. The identification of sakurasosaponin was based on analysis of spectroscopic data.