Antiproliferative polyketides from fungus Xylaria cf. Longipes SWUF08-81 in different culture media.

Bioactive compounds from the wood-decay fungus Xylaria cf. longipes SWUF08-81, cultivated in three different culture media (GM, YM and PDB), were isolated. Their structures and stereochemistry were deduced from spectroscopic and MS data analysis, together with quantum chemical calculations of 13C NMR chemical shifts and electronic circular dichroism (ECD) spectra. Five undescribed polyketides including dibenzofuran (1), mellein (2), dihydroisocoumarin (15), and two pyrans (16, 17), together with twenty-three compounds were determined. Compounds 18 and 20 were significantly toxic against cancer cell lines (HCT116, HT29, MCF-7 and HeLa) based on the MTT assay. Quantification by HPLC showed that 18 was produced three-fold higher in the broth of PDB than YM. These studies showed that the production of different compounds were primarily dependent on nutrition sources and it has given a starting point for the growth optimization conditions for the scaling up of bioactive compounds production.

A new amino amidine derivative from the wood-decaying fungus Xylaria cf. cubensis SWUF08-86.

The secondary metabolites of Xylaria cf. cubensis SWUF08-86 fungus were investigated, and the chromatographic separation of the crude extracts yielded seventeen compounds. The structure elucidation by spectroscopic analysis including 1D and 2D NMR and the comparison of these data with literature, along with HREIMS spectrometry, revealed one new amino amidine derivative (1), together with five known simple cyclic dipeptide analogs, diketopiperazines (2-6) and eleven other known compounds, including one hemi-cycline (10), three aromatic derivatives (11-13), one sesquiterpene (14) and three sterols (15-17). The isolated compounds were screened for anticancer and anti-pathogenic bacterial and fungal activities. Based on this work, Xylaria cf. cubensis SWUF08-86 has proven to be a diverse secondary metabolites producer.

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.

Chemical constituents, and their cytotoxicity, of the rare wood decaying fungus Xylaria humosa.

Samples of Xylaria humosa, a rare species of Xylariaceae, were collected during an investigation into the diversity of the fungus in the Phu Khieo Wildlife Sanctuary, Thailand. Nine compounds were isolated from the species and their structures elucidated by spectroscopic methods. The compounds were ergosterol (1), ergosterol peroxide (2), two meroterpenoids, chevalone B and C (3-4), together with five indole alkaloids, tryptoquivaline L (5), tryptoquivaline M (6), fiscalin A (7), epi-fiscalin A (8) and epi-fiscalin C (9). Compounds 2-9 exhibited variable cytotoxic activity against KB, NCI-H187 and MCF-7 cell lines.