青稞谷蛋白的结构解析及其功能特性研究  

Study on the Structure and Functional Properties of Highland Barley Glutenin

作　　者：邓婷 党斌 邝吉卫[1,2] 马萍 杨静 杨希娟 DENG Ting;DANG Bin;KUANG Jiwei;MA Ping;YANG Jing;YANG Xijuan(College of Agriculture and Animal Husbandry,Qinghai University,Xining,Qinghai 810016;Academy of Agricultural and Forestry Sciences of Qinghai University/Key Laboratory of Agricultural Products Processing in Qinghai Tibet Plateau,Xining,Qinghai 810016;Qinghai Tianyoude Technology Investment Management Group Co.,Ltd.,Xining,Qinghai 810000)

机构地区：[1]青海大学农牧学院,青海西宁810016 [2]青海大学农林科学院/青海省青藏高原农产品加工重点实验室,青海西宁810016 [3]青海天佑德科技投资管理集团有限公司,青海西宁810000

出　　处：《核农学报》2024年第8期1539-1549,共11页Journal of Nuclear Agricultural Sciences

基　　金：青海省重大科技专项(2021-NK-A3)。

摘　　要：为研究青稞中谷蛋白的结构特性、理化性质及功能特性,本研究采用超声波辅助Osborne分级法制备青稞谷蛋白,并采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)、红外光谱、差示扫描量热法(DSC)等方法评价青稞谷蛋白结构和基本性质。结果表明,青稞谷蛋白的颗粒形态完整,分子间排列疏松,分子量分布在30~50和75~100 kDa。二级结构分析表明,青稞谷蛋白主要以β-折叠(35.63%)和β-转角(34.31%)为主,存在少量的α-螺旋(11.82%)和无规则卷曲结构(11.76%)。热特性结果表明,青稞谷蛋白的热变性温度和焓变值分别为88.3℃和169.6 J·g^(-1),显示出良好的热稳定性。氨基酸组成结果表明,青稞谷蛋白富含谷氨酸和脯氨酸,必需氨基酸含量/总氨基酸含量为34.350%,其组成和配比合理。在等电点附近,青稞谷蛋白的溶解性、持水性、起泡性、泡沫稳定性、乳化性和乳化稳定性最差,而在65℃和pH值7的条件下,青稞谷蛋白溶解性和持水性最佳。同时,在5 g·L^(-1)的NaCl质量浓度下,青稞谷蛋白的起泡性及乳化性最佳;而添加蔗糖会降低其起泡性和泡沫稳定性。本研究结果可为青稞谷蛋白资源开发及其在食品加工中的应用提供理论依据。This study used an ultrasound-assisted Osborne classification method to isolate highland barley glutenin.The structural,physicochemical,and functional properties were evaluated using various analytical techniques including sodium dodecyl sulfate-polyacrylamide gel electrophoresis,infrared spectroscopy,and differential scanning calorimetry.The results showed an intact particle morphology of highland barley glutenin and a loose molecular arrangement with molecular weights distributed within 30-50 and 75-100 kDa.Secondary structure analysis indicated that the highland barley glutenin was mainly composed of β-sheet(35.63%)andβ-turn(34.31%),with a small amount ofα-helix(11.82%)and random coil structure(11.76%).Meanwhile,the isolated glutenin showed good thermal stability,as evidenced by a thermal denaturation temperature of 88.3℃and an enthalpy change value of 169.6 J·g^(-1).High levels of glutamic acid and proline were found among amino acids,with the essential amino acids constituting 34.35%of the total composition.Furthermore,highland barley glutenin exhibited optimal solubility and water holding capacity at 65℃and pH 7,while moderate salt concentrations(5 g·L^(-1))enhanced its foaming and emulsifying properties.However,the addition of sucrose significantly reduced its foaming capacity and foam stability.The findings of this study provided a theoretical foundation for the exploitation of highland barley gluten resources and their application in food processing.

关 键 词：青稞 谷蛋白 微观结构 功能特性 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]