Polyhydroxylated sterols from Monascus purpureus-fermented rice

Using a cell-based cytotoxicity assay, two new polyhydroxylated sterols, 16(S),22(S)-epoxy-3β,5α,6β,20(R),23(R),25-hexahydroxy-7-ergostene and 3β,7β,8α,25-tetrahydroxy-5,22E-ergostadiene were isolated from the ethyl acetate portion of the ethanolic extract of Monascus purpureus. Their structures were elucidated by spectroscopic analysis and in comparison with those reported in the literature. Both compounds showed cytotoxic activity against the lung adenocarcinoma (A549) with IC₅₀ values of 12.6 and 18.5 μM, exhibited moderate activities against human ovarian cancer (A2780), with IC₅₀ values of 8.8 and 9.4 μM.