Optimization of Enzymatic Preparation of Antioxidant Peptides from Tilapia by Response Surface Methodology

Response surface methods were used to optimize the hydrolysis conditions of Tilapia flesh by Protamex Protease for production of antioxidant peptides,and the effects of dosage of protease,ratio of material to water,time and hydrolysis temperature were investigated by the measurement of scavenging ?OH radical and DPPH.The Multi-factor regression equations were obtained to demonstrate ineractions among the factors and illustrate the different extent influence of preparation factors on ?OH and DPPH radical scavenging activity.Ratio of material to water and hydrolysis time showed the largest influence on ?OH and DPPH radical scavenging activity respectively.Then the optimum conditions of several parameters were obtained as follows: dosage of protease 750 U/g,ratio of material to water of 1:1,hydrolysis temperature of 45 °C,and hydrolysis time of 5 h,under which the antioxidative activity in scavenging ?OH and DPPH was shown to be 51.59% and 92.03% respectively.Furthermore,the effectiveness of response surface methodology had been verified by later experiments.