大米蛋白的木瓜酶酶解及其水解物的抗氧化活性

Enzymatic Hydrolysis of Rice Protein with Papain and Antioxidation Activity of Hydrolysate

以大米蛋白为原料,研究其酶解工艺及其水解物的抗氧化活性。选取底物浓度、加酶量、酶解pH、酶解温度为考察因素,进行了酶解工艺的单因素及正交试验。试验结果表明,底物浓度([S])10%,加酶量([E]/[S])5%,酶解pH 6.0,酶解温度60℃,酶解时间90 min为最佳酶解参数,在此条件下大米蛋白水解物的固形物含量为25.6 mg/mL,对DPPH自由基清除率为54.5%。抗氧化试验显示,大米蛋白水解物具有一定的清除DPPH自由基和羟自由基能力,其IC50分别为1.738和0.238 mg/mL。大米蛋白水解物同样也具有较强的还原能力。由此得出,大米蛋白水解物是一种天然的抗氧化肽。

The enzymatic hydrolysis technology of rice protein and the antioxidation activity of the hydrolysate were studied. Substrate concentration, enzyme dose, pH value and temperature were selected as factors to optimize the hydrolysis parameters with single - factor and orthogonal tests. Results show the optimum condition for the enzymatic hydrolysis is as follows： substrate concentration 10%, enzyme dose 5%, pH value 6.0, temperature 60 ℃, and time 90 min. Under the optimum condition, the soluble solid content of the hydrolysate is 25.6 mg/mL, and the DPPH free radical scavenging rate is 54.5%. Moreover, the result of an antioxidation experiment shows that the rice protein hydrolysate has very strong scavenging capabilities for DPPH free radical and hydroxyl radical, and their ICs0 are 1.738 and 0. 238 mg/mL respectively, showing a very strong reducing ability as well. In a word, rice protein hydrolysate is a sort of natural peptides with antioxidation activity.