乳清蛋白抗氧化肽的制备及体外抗氧化活性研究

Preparation of antioxidant peptides from whey protein and its in vitro antioxidant activity

采用酶解法制备乳清蛋白抗氧化肽并研究其体外抗氧化活性。结果表明:以羟自由基清除率和多肽含量为指标,筛选出中性蛋白酶为最优酶;在单因素试验的基础上,通过响应面试验确定最佳酶解条件为pH 5. 50、酶解温度65℃、酶解时间1. 65 h、底物质量分数5%、加酶量5 000 U/g,此条件下乳清蛋白抗氧化肽对羟自由基清除率为74. 54%;乳清蛋白抗氧化肽对羟自由基、ABTS+自由基、DPPH自由基和超氧阴离子自由基都具有较好的清除能力,IC50值分别为2. 174、0. 709、2. 813mg/m L和4. 579 mg/m L。表明乳清蛋白抗氧化肽具有较强的体外抗氧化活性,具有一定的开发利用价值。

The antioxidant peptides were prepared by the hydrolysis of whey protein with proteases,and its in vitro antioxidant activity was discussed.The results showed that the neutral protease was the best enzyme for the protein hydrolysis with the hydroxyl free radical scavenging rate and peptides content as indicators.Response surface methodology was carried out based on single factor experiment.The optimal hydrolysis conditions were obtained as follows:pH 5.50,hydrolysis temperature 65℃,hydrolysis time1.65 h,substrate mass fraction 5%and enzyme dosage 5 000 U/g.Under these conditions,the hydroxyl free radical scavenging rate of antioxidant peptides from whey protein was 74.54%.The antioxidant peptides from whey protein had good scavenging capabilities on hydroxyl free radical,ABTS+free radical,DPPH free radical and superoxide anions free radical,and the IC50 values were 2.174,0.709,2.813 mg/m L and 4.579 mg/m L respectively,which indicated that antioxidant peptides from whey protein had strong in vitro antioxidant activity,and had certain development and utilization value.