Identification of Secondary Metabolites from Marine Organism Associated Fungi

Abstract

Marine fungi have been the subject of extensive chemical and biological investigations in the last several decades. A large number of marine fungi have been isolated from various marine sources which include mangroves, sponges, algae and marine sediments, increasing in the order of numbers of strains isolated. In our research, we collected several sponges from Guggul-island, Korea and isolated some marine fungi from the cortex and core part of those sponges. From them, we conducted screening on five fungi species and chose one fungus strain for further study. Two new compounds and two known compounds, Ambuic acid and its derivatives, were isolated from Colletotrichum gloeosporioides strain. Compounds were evaluated for antibacterial activity by the 2-fold microtiter broth dilution method, but they did not display significant antibacterial activity. On the other hand, they displayed anti-inflammatory activity that inhibits nitric oxide production from RAW 264.7 macrophage cells over 50 μM. Also, research on three fungi strains isolated from Halocynthia roretzi was conducted. Among them, we focused on Aphanocladium sp. NW570b. One compound was isolated, but structure elucidation is on progress. Structure elucidation of all the compounds isolated was performed by analysis of LC-MS and NMR data (1H, 13C, COSY, HMBC and HSQC).