New polyketides from chemical mutant strain of sponge-associated fungus emericella variecolor xsa-07-2 / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the new bioactive secondary metabolites of diethyl sulfate chemical mutant strain of sponge-associated fungus Emericella variecolor XSA-07-2. METHODS: Diethyl sulfate was used to make chemical mutagenesis of strain XSA-07-2, and one mutant strain M8 was chosen for large-scale fermentation to generate new secondary metabolites. The compounds were isolated and purified by chromatography on silica gel and ODS reversed-phase column and semi-preparative HPLC techniques. And their structures were identified by their physicochemical properties and NMR, MS data analysis. RESULTS: Three new polyketides 1-3 were isolated from the extract of the solid fermentation culture of mutant strain M8. Compound 3 showed moderated antioxidant activity with IC50 of (13.58±0.14) μg·mL-1 by DPPH assay. CONCLUSION: Diethyl sulfate chemical mutagenesis can stimulate sponge-associated fungus Emericella variecolor XSA-07-2 mutant strain M8 to produce new antioxidant polyketides.