Metabolites and antifungal activities of an endophytic fungus Epicoccum sorghinum from mangrove

Objective  The metabolites of Epicoccum sorghinum L28 from mangrove and their antifungal activities were studied.

Method  The metabolites were isolated and purified by column chromatography, and their structures were identified by spectral technique. The minimum inhibitory concentration (MIC) of the metabolites against Fusarium graminearum and F. oxysporum were tested by the double dilution method.

Result  Ten compounds were isolated and identified as 7-hydroxy-2, 5-dimethyltrichroprimorone (compound 1), livistone A (compound 2), barceloneic acid A (compound 3), barceloneic lactone (compound 4), 2'-O-methylbarceloneate (compound 5), spirostaphylotrichin R (compound 6), spirostaphylotrichin U (compound 7), β-sitosterol (compound 8), β-carotenoside (compound 9) and β-adenosine (compound 10). 7-hydroxy-2, 5-dimethyltryptophanone displayed strong inhibitory effect against the growths of F. graminearum and F. oxysporum with MIC of 100 μg/mL. 2'-O-methylbarceloneate showed moderate inhibitory activity against F. oxysporum with MIC of 200 μg/mL.

Conclusion  Compounds 1 and 5 could be further studied as the lead compounds of corresponding antifungal pesticides.