CHEMICAL CONSTITUENTS AND ANTIMICROBIAL ACTIVITY OF THE MARINE SEDIMENT-DERIVED FUNGUS ASPERGILLUS sp. M793

Tóm tắt

In our ongoing search for bioactive compounds from marine-derived fungi, the ethyl acetate extract of Aspergillus sp. M793, isolated from marine sediment collected in Nha Trang - Khanh Hoa, Vietnam, exhibited strong antimicrobial activity against a panel of Gram-positive bacteria, including Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 14579, and the yeast Candida albicans ATCC 10231, with the MIC values of 8, 32, 32, and 8 µg/mL, respectively. A chemical investigation of the ethyl acetate extract led to the isolation of seven known compounds, including fumigaclavine C (1), pyripyropene A (2), 20-hydroxycyclotryprostatin (3), spinasterol (4), cerevisterol (5), monomethylsulochrin (6), and phenol A (7). Their structures were elucidated by detailed spectroscopic analyses, including MS and NMR data, and comparison with literature data. Notably, compounds 4 and 5 are reported here for the first time from the genus Aspergillus. Among the isolates, compounds 5-7 exhibited moderate to strong antimicrobial activity, with compound 7 showing the most pronounced and broad-spectrum effects, particularly against E. faecalis and C. albicans. These findings enrich the chemical inventory of marine-derived Aspergillus species and support their potential as promising sources of antimicrobial natural products.