To optimize the preparation process of an enzymatic hydrolysate with 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity from Hippocampus abdominalis.

Alcalase, flavor protease, trypsin, papain, trypsin, and pepsin were screened for DPPH scavenging activity, and alcalase was found to be optimal. The optimization of the hydrolysis process was conducted using a combination of single factor experiments and response surface methodology (RSM) based on Box-Behnken design. Hydrolysis time, pH, and enzyme/substrate (E/S) ratio were considered as independent variables. The in vitro antioxidant capacity of the hydrolysate was verified.

The optimal hydrolysis conditions were determined as 1:20, 11, 7.581%, 50 ℃ and 3 h for solid/liquid ratio, pH, E/S ratio, temperature and time, respectively. The DPPH scavenging activity of the as-prepared hydrolysate was 64.62%.

The optimized hydrolysis process can give peptides with high antioxidant activity from Hippocampus abdominalis.