驼乳与牛乳乳清蛋白酶解工艺优化及其产物抗氧化能力分析

为了研究不同蛋白水解酶对驼乳和牛乳抗氧化能力的影响,向驼乳和牛乳乳清蛋白中添加不同蛋白水解酶,探究乳清蛋白抗氧化活性肽的最佳制备条件,并对其抗氧化能力进行比较分析。首先从3种蛋白酶中筛选出最佳用酶,在此基础上以1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-Trinitrophenylhydrazine,DPPH)自由基的清除率为响应值,进行单因素和响应面试验,同时研究了驼乳和牛乳乳清蛋白抗氧化肽对DPPH自由基、羟自由基、超氧阴离子的清除效果。结果表明,木瓜蛋白酶水解物的能力最强,水解度可达15%。驼乳乳清蛋白最佳酶解工艺为酶解pH6.4,酶解温度55 ℃,底物浓度2.73%,DPPH自由基清除率可达71.9%。牛乳乳清蛋白最佳酶解工艺为酶解pH6,酶解温度54 ℃,底物浓度4%,DPPH自由基清除率达69.9%。在最佳酶解条件下,驼乳乳清蛋白酶解液的·OH清除率为58.2%,O₂-·清除率为67.2%;牛乳乳清蛋白酶解液·OH清除率为52.2%,·O₂-清除率为60.7%。驼乳乳清蛋白酶解液的抗氧化性在不同程度上均高于牛乳乳清蛋白酶解液,驼乳和牛乳乳清酶解液的DPPH自由基清除能力较强,其次是O₂-·清除能力,·OH清除能力最弱。

Optimization of Enzymatic Hydrolysis of Camel Milk and Milk Whey Protein and Analysis of Its Antioxidant Capacity

To investigate the effect of different proteolytic enzymes on the anti-oxidation ability of the camel and the cow, different proteolytic enzymes were added to the camel and the cow's milk whey protein to investigate the best preparation conditions of the anti-oxidation active peptide of the whey protein, then the anti-oxidation ability of the camel and the cow's milk whey protein was compared and analyzed. The best enzyme was selected from three kinds of proteases, on the basis of this, the clearance rate of the free radicals of 1, 1-diphenyl-2-trinitrobenzene (1, 1-diphenyl-2-trinitrophenyl) (DPPH) was used as the response value, the single factor and the response surface test were carried out, and at the same time, the scavenging effects of protein antioxidant peptides of camel milk and cow milk whey on DPPH free radical, hydroxyl free radical and superoxide anion were studied.The results showed that the hydrolysate of papain was the strongest, and the hydrolysis was up to 15%. The best enzymatic hydrolysis process was pH6.4, hydrolysis temperature 55℃, substrate concentration 2.73% of camel, the scavenging rate of DPPH radicalin the hydrolysate was 71.9%. And the optimum enzymatic hydrolysis process of cow whey protein was pH6, the temperature of enzymatic hydrolysis was 54℃, the substrate concentration was 4% under these conditions, the scavenging rates of DPPH in the hydrolysate were 66.9%. The scavenging rate of·OH and O₂-·in the hydrolysate was 58.2% and 67.2% of the camel, respectively. The scavenging rates of·OH and O₂-·in the hydrolysate were 52.2% and 60.7% of the cow, respectively.The antioxidant activity of camel whey protease hydrolysate was higher than that of cow whey protease hydrolysate to some extent, the scavenging ability of the DPPH free radical of the alpaca and the lactalbumin hydrolysate of the milk was strong, followed by O₂-·removal, and the ability of scavenging·OH was the weakest.