Protoilludene and Alkenoic Acid Derivatives from the European Polypore Fomitiporia hartigii .

Chemical investigation of the solid-state rice culture of the endangered European polypore Fomitiporia hartigii (Hymenochaetaceae) afforded a previously undescribed protoilludene derivative ( 1 ) in addition to six known compounds ( 2 - 7 ). Chemical structures of the isolated compounds were established based on HR-ESI-MS, comprehensive 1D/2D NMR spectroscopic analyses, and comparisons with the literature. All isolated compounds were assessed for their cytotoxic and antimicrobial activities. Among the tested compounds, hymeglusin ( 3 ) revealed potent cytotoxic activity against all tested cell lines with IC 50 values between 0.3 and 6.8 μM. Compound 3 and fusaridioic acid A ( 4 ) revealed weak to moderate antimicrobial activities with its most potent effect against Candida albicans (minimum inhibitory concentration of 4.2 μg/mL).