藜麦秸秆蛋白的结构和功能性质  

Structural and Functional Characteristics of Proteins in Quinoa Straw

作　　者：商海军 蒋丽君 江本利[1] 姚晓华[3] 闫晓明[1] 於春[1] SHANG Hai-jun;JIANG Li-jun;JIANG Ben-li;YAO Xiao-hua;YAN Xiao-ming;YU Chun(Institute of Cotton,Anhui Academy of Agricultural Sciences,Hefei 230031,Anhui,China;College of Food and Biological Engineering,Hefei University of Technology,Hefei 230601,Anhui,China;Qinghai Academy of Agriculture and Forestry Sciences,Xining 810016,Qinghai,China)

机构地区：[1]安徽省农业科学院棉花研究所,安徽合肥230031 [2]合肥工业大学食品与生物工程学院,安徽合肥230601 [3]青海省农林科学院,青海西宁810016

出　　处：《食品研究与开发》2022年第17期49-56,共8页Food Research and Development

基　　金：安徽省重点研究与开发计划项目(201904e01020010、202004e11020008);安徽省农业科学院学科建设专项项目(2021YL079)。

摘　　要：以藜麦秸秆为原料,利用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)、红外光谱和差示扫描量热法(differential scanning calorimetry,DSC)对从藜麦秸秆中提取到的蛋白质结构特性进行表征,并研究温度和pH值对藜麦秸秆蛋白功能性质的影响。结果表明,藜麦秸秆蛋白以中低分子量的蛋白质为主,分子质量主要分布为29.0 ku~44.3 ku和小于14.3 ku;热学特性研究结果显示:藜麦秸秆蛋白热稳定性较好,其变性温度为132.72℃,变性焓变为7.82 J/g;游离巯基和二硫键含量分别为10.21μmol/g和23.57μmol/g,藜麦秸秆蛋白二级结构中β-转角相对含量最高,为36.42%,α-螺旋含量为25.19%,β-折叠含量为25.91%,无规则卷曲含量为12.48%。温度为60℃时,藜麦秸秆蛋白的溶解性、吸水性和起泡性最佳,分别为53.61%、3.11 g/g和40.24%;pH值为9时,溶解性、吸水性和起泡性最好,分别为46.37%、3.34 g/g和40.86%。The structural characteristics of proteins extracted from quinoa straw were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),infrared spectroscopy and differential scanning calorimetry(DSC).The effects of temperature and pH on the functional properties of the proteins were studied.The results showed that the proteins mainly had medium and low molecular weight(29.0 ku-44.3 ku,or<14.3 ku).They demonstrated thermal stability,with denaturation temperature of 132.72℃and denaturation enthalpy of 7.82 J/g.The content of free sulfhydryl group and disulfide bond was 10.21μmol/g and 23.57μmol/g,respectively.As for the secondary structure,the relative content ofβ-turn,α-helix,β-sheet and random coil was 36.42%,25.19%,25.91%and 12.48%,separately.The solubility,water absorption and foamability were the best at 60℃,which were 53.61%,3.11 g/g and 40.24%,respectively.At pH 9,the proteins had the best performance in solubility,water absorption,and foamabilityt,and the corresponding values were 46.37%,3.34 g/g and 40.86%,separately.

关 键 词：藜麦秸秆 蛋白质 提取 结构特性 功能性质 

分 类 号：TS210.9[轻工技术与工程—粮食、油脂及植物蛋白工程]