Abstract: The aim of this study was to investigate the antioxidant and anti-aging effects and underlying mechanisms of inactivated Bacillus sp. DU-106 in Caenorhabditis elegans. The antioxidant activity of inactivated Bacillus sp. DU-106 was evaluated by in vitro free radical scavenging assay. The effects of inactivated Bacillus sp. DU-106 at various concentrations on the lifespan, stress response and antioxidant capacity of C. elegans were observed. The results illustrated that inactivated Bacillus sp. DU-106 possessed strong free radical scavenging capacity in vitro, meanwhile, inactivated Bacillus sp. DU-106 effectively extended the lifespan of C. elegans and improved its movement and stress resistance. Different concentrations of inactivated Bacillus sp. DU-106 increased the levels of catalase (CAT), superoxide dismutase (SOD) and glutathione in a dose-dependent manner. Fluorescence microscopy showed that treatment with inactivated Bacillus sp. DU-106 significantly reduced lipofuscin levels in C. elegans. In conclusion, inactivated Bacillus sp. DU-106 can exert an anti-aging effect perhaps by reducing lipofuscin accumulation and increasing the levels of antioxidant enzymes in C. elegans. This study provides a powerful basis for the development of Bacillus for application in nutraceuticals.

Key words: Bacillus sp. DU-106; Caenorhabditis elegans; anti-aging; antioxidant