Antifouling compounds from marine fungus Aspergillus iizukae GXIMD 00548

Twenty-three phenolic acids (1–23), including three novel sulfur-containing derivatives, along with five alkaloids (24–28) were isolated from the marine-derived fungus Aspergillus iizukae GXIMD 00548. Their structures were elucidated through comprehensive spectroscopic analysis and comparison with literature. All isolated compounds were evaluated for antifouling activities against barnacle larval settlement. Compounds 1–6, 8–11, 13, 20, 22 and 24–26 exhibited potent antifouling effects with median effect concentration (EC50) values ranging from 0.03 to 11.03 μg/mL. Additionally, compounds 9, 10 and 13 showed acetylcholinesterase (AChE) inhibitory effects with half maximal inhibitory concentration (IC50) values of 49.67 ± 0.08, 77.69 ± 0.09, and 127.5 ± 0.09 μM, respectively.