Anti-inflammatory constituents from a sea anemone-derived fungus Arthrinium arundinis MA30

In this study, preliminary field-sampling of bioactive fungal strains and bioassay-guided selection were conducted. A number of fungal strains were isolated from sea anemones along the northeastern coast of Badouzi, Keelung, Taiwan. Among them, Arthrinium arundinis MA30 showed significant anti-inflammatory activity and was thus selected for further chemical investigation. After a series of purification and isolation using different chromatographic techniques on the fermented products of A. arundinis MA30, thirty-one compounds were identified, five of which were previously unreported, including arthrinoic acid, hexylaconitic anhydride methyl ester, (3S,8R)-8-hydroxy-3-carboxy-2-methylenenonanoic acid, and arthripenoids G and H. These compounds were subjected to comprehensive spectroscopic data analysis. Of all the isolates, 1,3,5,6-tetrahydroxy-8-methylxanthone and arthripenoid C demonstrated the most distinctive inhibitory activities against nitric oxide production in mouse microglial BV-2 cells, with their respective inhibitory rates being 71% and 81% at 10 μM concentration, and their respective IC50 values were further determined to be 5.3 ± 0.6 and 1.6 ± 0.4 μM. These compounds showed no significant cytotoxicity, and curcumin was used as a positive control in this study.