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Seeking a strategy for triggering the cryptic natural product biosynthesis to yield novel compounds in the plant-associated fungus Xylaria sp., the effect of culture conditions on metabolite production was investigated. A shift in the production of five known cytochalasin-type analogues 1–5 to six new α-pyrone derivatives, xylapyrones A–F (compounds 6–11), from a solid to a liquid medium was observed. These compounds were identified by analysis of 1D and 2D NMR and HRMS data. Compounds 1–3 showed moderate cytotoxicity against HepG2 and Caski cancer cell lines with IC50 values ranging from 25 to 63 μM and compounds 4–11 were found to be inactive, with IC50 values &gt, 100 μM.

A novel metabolite containing sulfur, fusaodavinvin (1), was isolated from an endophytic fungus Fusarium sp.(CTGU-ZL-34), together with seven known compounds 2-8, and their structures were elucidated by NMR spectroscopy and MS. This is the first record of 3-(2R-hydroxyl-1-one-propane)-indole (compound 2) from nature. The isolated compounds were evaluated using the A549, Hep G2, Caski and MCF-7 cell lines by the MTT method, and compound 1 displayed significant inhibiting activity of four cancer cell lines with IC50 values of 11.5, 15.3, 15.2 and 60.5 μg/mL, respectively. However, compound 2 displayed no significant anticancer activity to the above four cancer cell lines.