【作者】 任丽琨； 范婧； 杨杨； 刘晓飞； 王冰； 边鑫； 王当丰； 徐悦； 刘宝祥； 朱鹏宇； 张娜；

【Author】 Ren Likun;Fan Jing;Yang Yang;Liu Xiaofei;Wang Bing;Bian Xin;Wang Dangfeng;Xu Yue;Liu Baoxiang;Zhu Pengyu;Zhang Na;College of Food Engineering,Harbin University of Commerce;College of Food Science and Technology,Jiangnan University;College of Food Science and Technology,Bohai University;

【机构】 哈尔滨商业大学食品工程学院； 江南大学食品学院； 渤海大学食品科学与工程学院；

【摘要】 米糠是精米加工的副产物,含有20%左右的蛋白质且具有氨基酸种类齐全、配比合理、低致敏性等特点,是重要的优质植物蛋白来源。本研究旨在评估米糠蛋白的抗氧化能力,并从米糠蛋白质酶解液中获得一种新的抗氧化肽。米糠蛋白分别用碱性蛋白酶、中性蛋白酶、胃蛋白酶、糜蛋白酶和胰蛋白酶水解,并对其抗氧化能力进行测定。胰蛋白酶水解物（T-RBPH）显示出高的Fe²⁺螯合活性(IC₅₀,2.271±0.007)、DPPH(IC₅₀,0.191±0.006)和羟基自由基清除能力(IC₅₀,1.038±0.034)。此外,T-RBPH对H₂O₂诱导的Caco-2损伤具有良好的修复能力。通过超滤、凝胶柱层析、快速蛋白液相色谱和LC-MS/MS对T-RBPH进行了纯化和鉴定。此外,通过计算机辅助及化学氧化测定,筛选得到具有低分子量（500～1500）、高抗氧化活性、良好安全性、溶解性并能与Keap1相互作用的AFDEGPWPK,其具有较强的ORAC（42.21±0.79μmol TE）和DPPH自由基能力（33.97%±0.01%）。此外,分子对接和Western bolt结果表明,AFDEGPWPK可以进入Keap 1-Kelch结构域的结合袋,通过激活Keap1/Nrf2/HO-1途径发挥抗氧化作用。更多还原

【Abstract】 Rice bran is a by-product of milled rice processing,which contains about 20% protein.It is an important source of high-quality plant protein because of its complete variety of amino acids,reasonable proportion and low allergenicity.The work aimed to assess the antioxidant ability and obtained a new antioxidant peptide from rice bran protein.Rice bran protein was hydrolyzed by Alcalase,Neutral,Pepsin,Chymotrypsin,and Trypsin,separately.Trypsin hydrolysate（T-RBPH）showed high Fe²⁺-chelating activity(IC₅₀,2.271±0.007),DPPH(IC₅₀,0.191±0.006),and hydroxyl radical scavenging ability(IC₅₀,1.038±0.034).Moreover,T-RBPH exhibited good repairability for H₂ O₂-induced damage of Caco-2.The T-RBPH was purified and identified by UF,GF,FPLC,and LC-MS/MS.Furthermore,AFDEGPWPK with low molecular weight（500-1500）,high antioxidant activity,good safety and solubility,and could interact with Keapl were screened by in silico method and determination of chemical oxidation,which exerted strong ORAC（42.21±0.79 μmol TE）and DPPH radical ability（33.97%±0.01%）.Moreover,the Molecular docking and Western bolt results showed that AFDEGPWPK could enter the binding pocket in the Kelch domain of the Keap 1-cavity and exerts antioxidant effects through activating Keap1/Nrf2/HO-1 pathway.更多还原