Preparation of Antioxidant Peptides From Sheep Placenta Byproductsby Enzymatic Hydrolysis

Abstract:

This study aimed to prepare antioxidant peptides from sheep placenta byproducts by enzymatic hydrolysis. Four proteases were used and degree of hydrolysis（DH） and DPPH radical scavenging activity were evaluated. Results showed that the hydrolysate by papain possessed the strongest DPPH radical scavenging activity in spite of a moderate DH. Through single factor tests and the response surface regression analysis，the optimal hydrolysis conditions by papain were thus obtained to be substrate concentration 33 mg/mL，pH 6.4，temperature 55 ℃，enzyme dosage 4 900 U/g and hydrolysis time 120 min. With these parameters，the hydrolysis resulted in a DH of 7.92 % and the hydrolysate had strong scavenging activities for radicals DPPH·，O2-·and ·OH with scavenging rates of 92.15 %，93.45 % and 48.88 %，respectively（10 mg/mL）.