New benzoate derivatives and hirsutane type sesquiterpenoids with antimicrobial activity and cytotoxicity from the solid-state fermented rice by the medicinal mushroom Stereum hirsutum

In addition to the fruiting bodies, mushroom mycelia can be used as functional foods and nutraceutical materials. In this study, two new benzoate derivatives (1 and 2) and three new sesquiterpenoids (3-5) were isolated from the mycelia of Stereum hirsutum. Their chemical structures were elucidated by NMR experiments. The absolute configuration in 3 was assigned by X-ray crystallographic analysis. In bioactivities evaluation, compounds 1 and 2 showed antimicrobial effects against methicillin-resistant Staphylococcusaureus, and S. aureus with the MIC values of 25.0 μg/mL; compounds 1 and 3 inhibited the NO overproduction in the LPS-induced macrophages with the IC50 values of 19.17 and 15.44 μM, and also displayed cytotoxicity against A549 and HepG2 with IC50 in the range of 10-50 μM. These results support the usage of the mycelia of S. hirsutum as a good functional food.