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摘要：为了提高麦谷蛋白的水解效率，本文采用双酶分步水解麦谷蛋白。以水解度为评 价指标，对双酶酶解麦谷蛋白的酶解条件进行优化。

本文研究中，筛选出了适宜水解麦谷蛋白的 2 种蛋白酶为中性蛋白酶和碱性蛋白 酶。加酶顺序对麦谷蛋白酶解的水解度有重要影响，理想的加酶顺序为：先加中性蛋 白酶进行第一步酶解，酶解结束后灭酶，加入碱性蛋白酶进行第二步酶解。在单因素 的基础上，优化出了最优第一步（中性蛋白酶）酶解条件为：酶解 pH 7、酶解温度 50℃、加酶量 4000U/g 和酶解时间 30min；最优第二步（碱性蛋白酶）酶解条件为： 酶解 pH 为 10、酶解温度为 55℃、加酶量为 9000U/g 和酶解时间 30min。在此条件下， 麦谷蛋白经双酶分步水解后，其水解度分别比中性蛋白酶和碱性蛋白酶的水解度提高 了 130%和 29%。分子量分布表明，双酶分步水解后麦谷蛋白酶解产物中≤68kDa 产 物明显增多，分别比中性蛋白酶和碱性蛋白酶提高了 121%和 17%。双酶分步水解后， 麦谷蛋白酶解产物的 DPPH 自由基清除活性比单酶酶解产物提高了 53%以上，其还 原力也比单酶酶解的高。

关键词：麦谷蛋白；双酶水解；分子量；抗氧化活性

Abstract：In order to improve the hydrolysis efficiency of glutenin, glutenin was hydrolyzed by the method of two-step hydrolysis. Taking degree of hydrolysis (DH) as evaluation index, hydrolysis conditions of glutenin by double-enzyme were optimized.

Neutral protease and alkaline protease, which were the most suitable for hydrolysis of glutenin, were chosen in this research. The order of adding enzyme had an important effect on DH of glutenin. The ideal order for adding enzyme was as follows: neutral protease was used as the first step hydrolysis; after the first step hydrolysis, this enzyme was inactivated and then alkaline protease was used as the second step hydrolysis. On the basis of single factor, the optimum hydrolysis conditions for the first step hydrolysis (neutral protease)

were hydrolysis pH 7, temperature 50℃, enzyme dosage 4000U/g and hydrolysis time   30

min. The optimum hydrolysis conditions for the second step hydrolysis (alkaline protease) were hydrolysis pH 10, temperature 55℃, enzyme dosage 9000U/g and hydrolysis time 30 min. Under this optimum condition, the DH of glutenin by two-step hydrolysis was increased, with an increase of 130% compared to that of neutral protease and an increase of 29% compared to that of alkaline protease. The results of molecular weight distribution showed that ≤68kDa fraction from hydrolysates of glutenin by double-enzyme hydrolysis was significantly increased, with an increase of 121% compared to that of neutral protease and an increase of 17% compared to that of alkaline protease. Double-enzyme hydrolysis caused an increase of above 53% in DPPH radical-scavenging activity of glutenin hydrolysates compared to that of single enzyme hydrolysis. In addition, the reducing power of hydrolysates of glutenin increased after double-enzyme hydrolysis.

Keywords: glutenin; double-enzyme hydrolysis; molecular weight; antioxidant activity

目录

第一章 绪 论 1

1.1  蛋白质的酶解 1

1.1.1  酶的种类 1

1.1.2  蛋白酶解产物的活性与研究 3

1.1.3  蛋白酶解的研究现状 4

1.2  麦谷蛋白 4

1.2.1  麦谷蛋白的概述 4

1.2.2  麦谷蛋白的提取及应用 5

1.2.3  麦谷蛋白的研究现状 (责任编辑：qin)