Metabolites of a symbiotic fungus Aspergillus clavatus XCE02 from Plutella xylostella and their antifungal activities

Objective  To study the metabolites of a symbiotic fungus Aspergillus clavatus XCE02 from Plutella xylostella and their antifungal activities against plant pathogens.

Method  The metabolites were isolated and purified by column chromatography. Their structures were elucidated by spectral analysis. The antifungal activities of the metabolites against Colletotrichum musae and Fusarium graminearum were investigated using paper disc-agar diffusion method.

Result  Ten compounds were isolated and identified as gliomasolide A, Sch725674, gliomasolide C, clavatustide A, clavatustide B, 20-hydroxyergosta-4, 6, 8(14), 22-tetraen-3-one, xanthine, ergosterol, ergosterol peroxide and butanedioic acid. At the concentration of 250 μg/mL, gliomasolide A, Sch725674 and gliomasolide C exhibited high inhibitory activities against C. musae and F. graminearum, clavatustide A and clavatustide B showed moderate inhibitory activities against C.musae and F.graminearum and 20-hydroxyergosta-4, 6, 8(14), 22-tetraen-3-one showed moderate inhibitory activity against F.graminearum.

Conclusion  Gliomasolide A, gliomasolide C and 20-hydroxyergosta-4, 6, 8(14), 22-tetraen-3-one have been obtained from the genus Aspergillus in this study. Gliomasolide A, Sch725674 and gliomasolide C can be used as leading compounds for developing antifungal pesticide.