超声功率对小麦醇溶蛋白-膳食多酚共价复合物结构及功能性质的影响  

Effect of Ultrasonic Power on the Structural and Functional Properties of Gliadin Protein-Dietary Polyphenol Conjugates

作　　者：曹佳兴 朱海兰 王君荣 张健豪 张国治[1,4] CAO Jiaxing;ZHU Hailan;WANG Junrong;ZHANG Jianhao;ZHANG Guozhi(College of Cereal and Food,Henan University of Technology,Zhengzhou 450001,China;College of Food Science and Engineering,Zhengzhou University of Science and Technology,Zhengzhou 450001,China;School of Agriculture and Biology,Shanghai Jiao Tong University,Shanghai 201100,China;Henan Province Wheat-Flour Staple Food Engineering Technology Research Centre,Zhengzhou 450001,China)

机构地区：[1]河南工业大学粮油食品学院,河南郑州450001 [2]郑州科技学院食品科学与工程学院,河南郑州450001 [3]上海交通大学农业与生物学院,上海201100 [4]河南省面制主食工程技术研究中心,河南郑州450001

出　　处：《食品科学》2023年第19期65-73,共9页Food Science

基　　金：河南省重大科技专项(151100111300);河南工业大学自科创新基金支持计划专项(2020ZKCJ20)。

摘　　要：本研究选择自由基氧化反应诱导小麦醇溶蛋白(gliadin,GL)与表没食子儿茶素没食子酸酯进行共价反应,比较不同功率超声波(ultrasound,US)对共价反应强化效果的影响,旨在提高多酚在蛋白质改性中的生物利用率。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、高效液相色谱和Folin-Ciocalteu实验验证多酚的共价修饰。通过紫外光谱、圆二色光谱分析共价复合物的结构变化。结果表明:US破坏了蛋白质内部的弱作用力,引起分子结构解聚。蛋白质的亲水/疏水氨基酸残基转移,三级结构趋于松散,这一过程改变了分子表面的基团分布,提高了蛋白水溶性。此外,GL空间结构的转变暴露出更多的酶切位点,使其更容易被消化。本研究中,在US与自由基氧化的协同作用下,共价复合物中抗氧化分子的负载量增加,表现出更强的自由基清除活性。In this study,free radical oxidation was chosen to induce covalent reaction of gliadin(GL)with epigallocatechin gallate.The effects of different ultrasound(US)powers on the enhancement of the covalent reaction were compared with the aim of improving the bioavailability of polyphenols in protein modification.Covalent modification of polyphenols was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),high-performance liquid chromatography(HPLC)and the Folin-Ciocalteu assay.The structural changes of the covalent complexes were analyzed by ultraviolet(UV)spectroscopy and circular dichroism(CD)spectroscopy.The results showed that US disrupted weak intra-protein forces,which caused molecular depolymerization.The hydrophilic/hydrophobic amino acid residues of the protein were shifted and the tertiary structure tended to be looser,and this process altered the distribution of groups on the molecule surface and increased the water solubility of the protein.Furthermore,the shift in the spatial structure of GL resulted in the exposure of more enzyme cleavage sites,making its digestion easier.The synergistic effect of US and free radical oxidation increased the loading of antioxidant molecules onto the covalent complexes,resulting in stronger free radical scavenging activity.

关 键 词：超声波 小麦醇溶蛋白 表没食子儿茶素没食子酸酯 蛋白结构 功能特性 

分 类 号：TS201.2[轻工技术与工程—食品科学]