Thielavins W-Z7, new antifouling thielavins from the marine-derived fungus thielavia sp. UST030930-004

Abstract

Eleven new depsides - thielavins W-Z (1-4) and thielavins Z1-Z7 (5-11) - and also four known thielavins - A, H, J, and K (12-15) - were isolated from the ethyl acetate extract of a marine-derived fungal strain Thielavia sp UST030930-004. All of these compounds were evaluated for antifouling activity against cyprids of the barnacle Balanus (=Amphibalanus) amphitrite. The results showed that compounds 1-3 and 6-13 were active, with EC50 values ranging from 2.95 ± 0.59 to 69.19 ± 9.51 μM, respectively. The inhibitive effect of compounds 1-3 and 7 was reversible. This is the first description of the antifouling activity of thielavins against barnacle cyprids.