Antimalarial and cytotoxic constituents of Xylaria cf. cubensis PK108.

Xylaria cf. cubensis PK108 was identified by its distinctive morphological characteristics and its internal transcribed spacers sequence analysis. The chromatographic separation and structural elucidation based on spectroscopic analysis of fungal crude extracts led to 10 compounds; tryptoquivaline L (1), fiscalin C (2), epi-fiscalin C (3), cytochalasin D (4), ergosterol (5), ergosterol peroxide (6), chevalone C (7), xylaranol B (8), helvolic acid (9) and cyclo-(L-Pro-L-Leu) (10). The bioassay screening showed that 4 displayed cytotoxicity against KB and NCI-H187 cancer cell lines with IC50 values of 3.25 and 5.95 μg mL(-1). 6 exhibited cytotoxicity against NCI-H187 with an IC50 value of 5.81 μg mL(-1). 7 and 9 showed antimalarial activity with IC50 values of 25.00 and 6.25 μg mL(-1), respectively. This result establishes Xylaria as broad spectrum bioactive compound producers.