杜仲籽粕水解肽的制备及其抗氧化活性分析

以碱提酸沉得到的杜仲籽粕蛋白为原料，以水解度和总抗氧化能力（T-AOC）为指标，在单因素实验的基础上，以酶添加量、酶解时间和底物浓度为考察因素，采用Box-Behnken法进行三因素三水平响应面试验优化设计得出杜仲籽粕水解肽的制备最佳工艺参数，并对得到的杜仲籽粕水解肽进行体外抗氧化测定。结果表明，中性蛋白酶为最优蛋白酶，最佳酶解条件为酶添加量10000 U/g，酶解时间1.50 h，底物浓度20 g/L，在该条件下的水解度为47.45%±1.50%，T-AOC为30.62±0.59 μmol/g；最佳工艺下得到的杜仲籽粕水解肽，对DPPH自由基、超氧阴离子自由基以及ABTS自由基清除率的IC₅₀值分别为0.731、4.258、0.407 mg/mL，表现出良好的抗氧化性，为杜仲籽粕高值化利用及抗氧化肽功能产品开发提供理论依据。

Preparation and Antioxidant Activity Analysis of Hydrolyzed Peptides from Eucommia ulmoides Seed Meal

Eucommia ulmoides seed meal protein prepared by alkali extraction and acid precipitation was utilized as raw material. On the basis of single factor experiment, the total evaluation value of the hydrolysis degree and total antioxidant capacity (T-AOC) as response value was used to optimize the addition of enzyme, hydrolysis time and substrate concentration. And the Box-Behnken method was used for three factors and three levels response surface test design to determine the best enzymatic preparation process of hydrolyzed peptides from Eucommia ulmoides seed meal. The antioxidant activity of the obtained hydrolyzed peptides was determined in vitro. The results showed that neutral protease was the best protease, and the best enzymatic hydrolysis condition were enzyme was 10000 U/g, hydrolysis time 1.50 h and substrate concentration 20 g/L. Under these conditions, the degree of hydrolysis and T-AOC of hydrolyzed peptides were 47.45%±1.50% and 30.62±0.59 μmol/g, separately; the IC₅₀ for DPPH free radical, superoxide anion radical and ABTS free radical scavenging rates were 0.731, 4.258 and 0.407 mg/mL, respectively. The Eucommia ulmoides seed meal peptides prepared under these conditions had great antioxidant capacity and provided a theoretical basis for the high-value utilization of Eucommia ulmoides seed meal and the development of antioxidant peptide functional products.