Antioxidant and Antimicrobial Tests of Extracts from Solid Culture of Isaria farinosa Strains

WANG Yong-hui;GUO Chen-yu;WANG Wen-jing;JIANG Lan;LI Yi;WU Hong-mei;YAO Yi-jian;State Key Laboratory of Mycology,Institute of Microbiology,Chinese Academy of Sciences;University of Chinese Academy of Sciences;Beijing No.8 High School;College of Plant Protection,Fujian Agriculture and Forestry University;

Isaria farinosa;;Paecilomyces hepiali;;crude ethyl acetate extracts;;antioxidant effects;;antimicrobial activity;;strain variation

Isaria farinosa is a widely distributed entomopathogenic fungus in soil-dwelling insects. It has been extensively studied and applied in biological control of insects,and also attracted researchers' attention for its pharmacological effects and bioactive metabolites. In this study,seven strains of I. farinosa from different origins were selected based on morphological and molecular identification to reveal the variation among strains. Antioxidant effects and antimicrobial activities were tested by crude ethyl acetate extracts from the strains cultivated on rice medium. The results showed that the strains displayed significant variations in the bioactivities tested under the same conditions and strain 2142 had the best performance. In particular,the crude extract( 200 mg/m L) from strain 2142 had the similar effect with Bacillus cereus to that of ampicillin sodium( 80 μg/m L) used as the positive control in the antimicrobial experiment. Further investigation on the strain was required to explore its potentials. There arebroad prospects for the application of I. farinosa in health foods and pharmaceutical product,but the caution should be taken in the selection of strains for such purposes. It is important to evaluate the safety of any strain before its application in the area associated with human health.