Polyketides and Meroterpenes from the Marine-Derived Fungi Aspergillus unguis 158SC-067 and A. flocculosus 01NT-1.1.5 and Their Cytotoxic and Antioxidant Activities

Ten secondary metabolites, including a new grifolin analog, grifolin B ( ); a new homovalencic acid derivative, 12-hydroxyhomovalencic acid ( ); and a compound isolated from a natural source for the first time ( ), along with seven known compounds, grifolin ( ), averantin ( ), 7-chloroaverantin ( ), 1'- -methylaverantin ( ), 7-hydroxy-2-(2-hydroxypropyl)-5-pentylchromone ( ), homovalencic acid ( ), and bekeleylactone E ( ), were isolated from two fungal strains. The structures of - were identified by detailed analysis and comparison of their spectroscopic data with literature values. Compounds and showed moderate cytotoxic activity against a panel of cancer cell lines (PC-3, HCT-15, MDA-MB-231, ACHN, NCI-H23, NUGC-3), with the GI values ranging from 1.1 µM to 3.6 µM, whereas displayed a weak 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity without cytotoxicity against all tested cell lines.