Bioactive saponins from Swartzia schomburgkii from the Suriname rainforest

Bioassay-guided fractionation of the MeOH extract of Swartzia schomburgkii using the engineered yeast strains 1138, 1140, and 1353 as the bioassay too l resulted in the isolation of five, active (2, 4-7) and three inactive (1, 3, 8) saponins. Saponins 4 and 6 are previously unreported. The structures of all of the saponins were established based on 1D and 2D NMR spectral an alysis, on acid and alkaline hydrolysis followed by TLC and GC-MS, and by c omparison with literature data for known compounds. Three of the isolated c ompounds (4-6) showed weak cytotoxicity against the M-109 cell line.