Abstract:The protein was extracted from Gɑnodermɑ lucidum spore powder by alkaline extraction and acid precipitation method， and peptides with antioxidant activity was screened out by enzymatic hydrolysis with protease. By using DPPH free radical scavenging rate and degree of hydrolysis as evaluation indexes， the enzymatic hydrolysis process of the antioxidant peptide from Gɑnodermɑ lucidum spore powder was optimized by single factor test and response surface method， and the antioxidant properties of the protease hydrolysate products of Gɑnodermɑ lucidum spore powder and their stability under different temperatures， pH values， and metal ion conditions were investigated. The results showed that the products of Gɑnodermɑ lucidum spore powder protein hydrolyzed by alkaline protease showed the strongest antioxidant activity. When the enzyme addition amount was 2 000 U/g， the enzymatic hydrolysis time was 3 h， the enzymatic hydrolysis temperature was 50 ℃， pH was 8， and the substrate concentration was 0.50%， the enzymatic hydrolysis products had the best antioxidant activity. At 60 ℃， the antioxidant peptide of Gɑnodermɑ lucidum spore powder showed good thermal stability. It was stable in acidic environment and in the presence of Mg2+.