两步水解法制备玉米-大豆复合抗氧化肽及其稳定性研究  

Preparation of compound antioxidant peptide from zein-soy protein isolated by two-step hydrolysis and evaluation on its stability

作　　者：王晓杰 刘晓兰 曲悦 夏春荣 SUKHIKH Stanislav ANDREYEVA Anna WANG Xiaojie;LIU Xiaolan;QU Yue;XIA Chunrong;SUKHIKH Stanislav;ANDREYEVA Anna(Heilongjiang Key Laboratory of Corn Deep Processing Theory and Technology,College of Food and Biological Engineering,Qiqihar University,Qiqihar 161006,Heilongjiang,China;Department of Microbiology and Biotechnology,Life System Institute,Immanuel Kant Baltic Federal University,Kaliningrad 236016,Russia)

机构地区：[1]齐齐哈尔大学食品与生物工程学院,黑龙江省玉米深加工理论与技术重点实验室,黑龙江齐齐哈尔161006 [2]康德波罗的海联邦大学生命系统研究所,微生物学和生物技术实验室,俄罗斯加里宁格勒236016

出　　处：《中国油脂》2021年第3期39-47,共9页China Oils and Fats

基　　金：黑龙江省省属高等学校基本科研业务费青年创新人才科研项目(135309345);植物性食品加工技术黑龙江省优势特色学科资助项目(YSTSXK201819)。

摘　　要：采用麦芽粉和碱性蛋白酶Alcalase两步水解玉米醇溶蛋白和大豆分离蛋白的混合物(质量比1∶1)制备复合抗氧化肽,以水解度、可溶性蛋白含量和抗氧化活性为指标,对第二步Alcalase的水解条件进行优化,确定两步水解法制备复合抗氧化肽的最适条件。另外,对复合抗氧化肽相对分子质量分布、稳定性和氨基酸组成进行了研究。结果表明,制备复合抗氧化肽的最适条件为在底物质量分数10%、pH 5.5、50℃、酶(麦芽粉)底质量比30%条件下水解3 h后,再在底物质量分数10%、pH 8.5、60℃、酶(Alcalase)底质量比0.75%条件下继续水解3 h。在最适条件下,水解度、可溶性蛋白含量、羟自由基清除率和亚铁离子螯合率分别为36.32%、36.83 mg/mL、40.01%和86.83%,相对分子质量主要分布在300~6 500 Da (含量92.44%)范围内,必需氨基酸指数(EAAI)值为8.02(n=9),属于优质蛋白源。复合抗氧化肽具有热稳定性,在中性及碱性条件下稳定,但不耐受酸性(pH 3~5)、4℃贮存和反复冻融的加工条件。The compound antioxidant peptide was prepared by two-step hydrolysis of zein-soy protein isolate (mass ratio of 1∶1) with malt flour and alkaline protease Alcalase. The second stage hydrolysis conditions of Alcalase were optimized by determining hydrolysis degree,soluble protein content and antioxidant activities. Moreover,the relative molecular weight distribution,stability and the amino acid composition of compound antioxidant peptide were investigated. The results showed that the optimal conditions for the preparation of compound antioxidant peptide were obtained as follows: the first stage hydrolysis conditions of substrate mass fraction 10%,pH 5. 5,temperature 50 ℃,and mass ratio of enzyme (malt flour) to substrate 30%,hydrolysis time 3 h;the second stage hydrolysis conditions of substrate mass fraction 10%,pH 8. 5,temperature 60 ℃, mass ratio of enzyme (Alcalase) to substrate 0. 75% and hydrolysis time 3 h. Under these conditions,the hydrolysis degree,soluble protein content,hydroxyl radical scavenging rate and ferrous ion chelation ability were 36. 32%,36. 83 mg/mL,40. 01% and 86. 83%,respectively. Meanwhile,the relative molecular weight of the compound antioxidant peptide was mainly distributed in the range of 300-6 500 Da (92. 44%),and the essential amino acid index value was 8. 02 (n = 9),which indicated that the peptide prepared was a high-quality protein source. The compound antioxidant peptide had thermal stability,and it was stable in neutral and alkaline conditions.However,acidic condition (pH 3-5),4 ℃ storage and repeated freezing-thaw reduced the antioxidant activity of the compound antioxidant peptide.

关 键 词：麦芽粉 两步水解 玉米醇溶蛋白 大豆分离蛋白 玉米-大豆复合肽 抗氧化活性 稳定性 

分 类 号：TS229[轻工技术与工程—粮食、油脂及植物蛋白工程] TQ936[轻工技术与工程—食品科学与工程]