Antioxidant metabolites from marine alga-derived fungus Aspergillus wentii EN-48

Eight secondary metabolites (1-8) including a new seco-anthraquinone (wentiquinone C, 1) and a new benzamide derivative (methyl 4-(3,4-dihydroxybenzamido) butanoate, 2), as well as three other derivatives (4, 7, and 8) that were isolated from natural source for the first time, were characterized from the EtOAc extracts of the marine alga-derived endophytic fungus Aspergillus wentii EN-48. The structures of the isolated compounds were elucidated on the basis of 1D and 2D NMR experiments. Each of the isolated compounds was evaluated for a, a-diphenyl-picrylhydrazyl (DPPH) radical scavenging activity, and some of them showed potent activities with IC50 values ranging from 5.2 to 99.4 mu g/mL, compared to the positive control, butylated hydroxytoluene (BHT), with an IC50 of 36.9 mu g/mL. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.