Secondary metabolites from a fungus Peniophora sp.isolated from a gorgonian Echinogorgia sp.

Objective To investigate the secondary metabolites and their bioactivities of symbiotic fungus Peniophora sp.associated with the gorgonian Echinogorgia sp.collected from the South China Sea.Methods Column chromatography on silica gel,Sephadex LH-20,recrystallization and semi-preparative HPLC were used to isolate and purify the compounds from EtOAc extract of the fermentation broth.Their structures were elucidated by spectroscopic techniques(NMR,MS) and compared with the reported spectral date.Brine Shrimp lethal Toxicity and Zebrafish Embryo Toxicity models were used to evaluate their bioactivities.Results Seven sterols were isolated and identified as 4-hydroxy-17R-methylincisterol(1),ergosterol(2),(3β,5α,6β,22E)-6-methoxyergosta-7,22-diene-3,5-diol(3),cerevisterol(4),ergosta-4,6,8,22-tetraen-3-one(5),ergosterol peroxide(6) and 9,11-dehydroergosterol peroxide(7).Conclusion Compound 1 showed significant lethal activity toward brine shrimp Artemia salina with a mortality rate of 88.4% at the concentration of 25 μg·mL-1.Compound 4 exhibited potent fish toxicity causing embryo notochord malformation of zebrafish Danio rerio with a EC50 value of 7.83 μg·mL-1(72 h).