Objective: To study the bioactive constituents from tubers of Bolbostemma paniculatum.
Method: Compounds were isolated by extraction and partition as well as several-chromatographic techniques guided with Pyricularia oryzae bioassay method. Their structures were determined on the basis of spectral analysis and chemical evidence.
Result: Bisdesmoside (I) was isolated as active compound causing morphological abnormality of Pyncularia oryzae mycelia and elucidated as 3-0-alpha-L-arabinopyranosyl (1-->2)-beta-D-glucopyranosyl-bayogenin-28-O-beta-D-xylopyranosyl (1-->3)-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranoside.
Conclusion: I is a new natural product and exhibited significant cytotoxicity against cancer cell lines K-562 and BEL-7402, but no hemolytic activity to rabbit erythrocytes.