Abstract: In this study, Cordyceps militaris (L.) Fr.-fermented rice was obtained by solid-state fermentation of rice with C.?militaris?(L.)?Fr., and its antioxidant activity was studied. The optimization of fermentation conditions was carried out using one-factor-at-a-time and orthogonal array design. The contents of cordycepic acid and water-soluble non-starch polysaccharides (SNSP) were used as response variables. The in vivo anti-aging activity of fermented rice was assessed by measuring the lifespan of Drosophila melanogaster, and antioxidant enzyme activities and malondialdehyde (MDA) content in this organism. Results showed that the optimum fermentation conditions were determined as follows: ratio of material to water 1:1.0, inoculum amount 20 mL/100 g, fermentation temperature 22 ℃, and fermentation time in the dark 8 days. For each dietary supplementation level, the half death period, average life expectancy, maximum life expectancy of Drosophila melanogaster given the fermented rice were higher than those of the blank control group and the rice control group. The activities of superoxide dismutase and catalase in the experimental group were higher than those in the control group, and the enzyme activities increased with increasing supplementation level. MDA content in the experimental group was lower than that in the blank group, and it decreased with increasing addition of C.?militaris?(L.)?Fr.-fermented rice.

Key words: Cordyceps?militaris?(L.)?Fr.-fermented rice, fermentation optimization, anti-aging activity in vivo