Simple and rapid screening of entomopathogenic fungi having radical-scavenging and anticancer activities

Entomopathogenic fungal metabolites exhibit a wide variety of insecticidal, antimicrobial, anticancer, antioxidant, and antiviral activities, and they have been suggested as potential candidates for the development of new bioactive agents. The rapid and simple screening of entomopathogenic fungi with such bioactivities is important for investigating bioactive substances. The radical-scavenging and anticancer activities of 28 species and 20 genera of 342 isolates of entomopathogenic fungi were evaluated using only culture filtrates. As a result, 23 isolates of Metarhizium anisopliae var. anisopliae, 1 isolate of Pochonia sp., and 1 isolate of Aspergillus sp. showed high radical-scavenging activity. Additionally, anticancer activity in HCT116 human colon cancer cells was also confirmed for selected culture filtrates. This simple screening method of entomopathogenic fungi using culture filtrates may be useful for the rapid detection of related substances with pharmacological activity from a large number of fungal samples.