富硒糙米抗氧化肽酶法制备工艺优化

Optimization of Antioxidant Peptides from Se-enriched Brown Rice Proteins by Enzymolysis

以富硒糙米蛋白为原料,优化富硒糙米蛋白抗氧化肽酶法制备工艺。以酶解产物抗氧化能力指数(oxygen radical absorbance capacity,ORAC)和水解度为评价指标,考察酶种类、酶解时间、pH值、底物浓度、加酶量及酶解温度对酶解产物抗氧化活性的影响。在单因素试验基础上,采用三因素三水平响应面法确定富硒糙米抗氧化肽的制备工艺。结果表明:中性蛋白酶较适宜制备富硒糙米抗氧化肽,其最佳酶解工艺条件为:pH 8.0,底物浓度3%,酶解时间69 min,酶解温度55℃,加酶量12 000 U/g。在此条件下,富硒糙米蛋白酶解产物的抗氧化能力为(1 232.57±62.34)μmol TE/g,显著高于同等条件下非富硒糙米蛋白酶解物的抗氧化能力。

The preparation process of antioxidant peptides from selenium-enriched brown rice(Se-BR)protein hydrolysates were optimized in this study.Effects of six factors including enzymes,hydrolysis time,pH,substrate concentration,enzyme dosage and temperature on the oxygen radical absorbance capacity(ORAC)and degree of hydrolysis(DH)were evaluated.Based on the single factor experiments,a procedure optimized using the response surface analysis with three factors(hydrolysis time,temperature and enzyme dosage)was conducted in order to obtain the optimal enzymolysis conditions.The results showed that neutral protease was suitable for producing antioxidant peptides from Se-BR protein.The optimal enzymolysis conditions were as follows:pH value of 8.0,substrate concentration of 3%,enzymolysis time of 69 min,enzymolysis temperature of 55℃and enzyme dosage of 12 000 U/g protein.Under the conditions,the antioxidant capacity of the Se-BR proteolysis product was(1 232.57±62.34)μmol TE/g,which was significantly higher than that of the non-Se-BR protein under the same conditions.