Bioactive metabolites from a hydrothermal vent fungus aspergillus sp. YQ-13

Abstract

To study fermentation from strain Aspergillus sp. YQ-13, dwelling in sediment Kueishantao hydrothermal vents off Taiwan. Compounds were separated and purified by silica gel column, preparative HPLC techniques.Their structures were identified by the physicochemical properties and spectral analysis. The isolates were identified as 3-hydroxy-2-(2-hydroxy-6-methoxy-4-methylbenzoyl)-5-methoxy-benzoic acid methyl ester (1), myristic acid (2), orcinol (3), 1,2- seco-Trypacidin (4), leporin A (5), chaetominine (6), 5-hydroxy-2-hydroxymethyl-4H-pyran-4one (7) and N-methyl-2-pyrolidinone (8). Compound 1 was identified as a new natural product belonging to diphenyl ketone family. Known compounds 5 and 6 exhibited antibiotic activity with MIC value of around 1 to 25 μg mL-1 against Bacillus subtilis, Klebsiella pneumoniae, methicillin resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Acinetobacter Bauman. Compounds 1, 4, 5 and 6 were tested by the methods of DPPH and FRAP assay, showing moderate antioxidant activities.