双酶水解麦胚制备抗氧化肽的工艺优化

Optimization of Preparation of Wheat Germ Antioxidant Peptides with Two Enzymes

以麦胚为原料,制备具有抗氧化活性的麦胚肽。对碱性蛋白酶Alcalase 2.4 L与胰蛋白酶双酶组合酶解麦胚的工艺进行优化。以水解度和1,1-二苯基苦基苯肼(DPPH)自由基清除率为考察指标,探讨酶与底物浓度的比值([E]/[S])、酶降温度和酶解时间对制备麦胚抗氧化肽工艺的影响,采用Box-Behnken中心组合设计和响应面法(RSM)优化了麦胚双酶水解的工艺条件。结果表明:双酶水解麦胚制备抗氧化肽的工艺条件为底物浓度10.0%、碱性蛋白酶与胰蛋白酶酶活比1∶1、[E]/[S]为0.041 3、酶解温度50.3℃、酶解时间2.03 h、pH8.0。验证试验表明,在此条件下,麦胚水解度和抗氧化肽对DPPH自由基清除率分别为16.65%和50.16%;其抗氧化活性小于10 mg/ml VC。

The aim of this study was to prepare antioxidant peptide from wheat germ,which was hydrolyzed by the mixture of alkali protease Alacase 2.4 L and trypsinase.Taking the degree of hydrolysis（DH） and the scavenging rate of DPPH free radical activity as indexes,the effects of ratio of enzyme to substrate（）,enzymolysis temperature and time on the technology were analyzed and optimized using Box-Behnken design and response surface methodology（RSM）.The results showed that the optimum conditions were as follows：substrate concentration of 10.0%,pH value 8.0,the ratio of alkali protease Alcalase 2.4 L to trypsinase activity at 1∶1, 0.041 3,enzymolysis temperature at 50.3 ℃ for 2.03 h.Under these conditions,the DH of enzyme-hydrolyzed product and the scavenging rate of DPPH free radical activity by the antioxidant peptides were 16.65% and 50.16%,respectively,and the antioxidant activity of the antioxidnt peptides was less than that of 10 mg/ml VC.