Abstract:

This paper reports on the optimization of preparation conditions for antioxidant peptides by hydrolyzing fertilizedegg white with alkaline protease. One-factor-at-a-time method was used to explore the effect of hydrolysis temperature,pH, substrate concentration and enzyme amount on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activityof hydrolysates. Subsequently, the response surface analysis based on Box-Behnken design was employed to optimize thehydrolysis conditions. The results showed that hydrolysates showing the highest DPPH scavenging rate of 84.97% wereproduced from hydrolysis of fertilized egg white at a substrate concentration of 4.28 g/100 mL at 46 ℃ and pH 9.1 withan enzyme amount of 21 000 U/g. In conclusion, peptides with high antioxidant activity can be prepared by hydrolyzingfertilized eggs with alkaline protease and the optimized conditions allow accurate theoretical prediction.

Key words: fertilized egg, antioxidant peptide, enzymatic hydrolysis, response surface methodology