不同莲子蛋白氨基酸结构与热特性研究  

Amino Acid Structure and Thermal Properties Study on Different Lotus Seed Proteins

作　　者：孙乾 郭增铮 郑玮雯 吴钰涵 郭泽镔[2] SUN Qian;GUO Zeng-zheng;ZHENG Wei-wen;WU Yu-han;GUO Ze-bin(College qf Food Science,Fujian Agriculture and Forestry University,Fuzhou 350000,China;China-Ireland International Cooperation Centre for Food Material Science and Structure Design,Fujian Agriculture and Forestry University,Fuzhou 350000,China;Jin Shan College,Fujian Agriculture and Forestry University,Fuzhou 350000,China)

机构地区：[1]福建农林大学食品科学学院,福州350000 [2]福建农林大学中爱国际合作食品物质学与结构设计研究中心,福州350000 [3]福建农林大学金山学院,福州350000

出　　处：《中国食物与营养》2023年第2期45-51,共7页Food and Nutrition in China

基　　金：福建省自然科学基金面上项目(项目编号:2020J01559);福建农林大学科技创新专项基金(项目编号:CXZX2019092G)。

摘　　要：目的:研究不同莲子蛋白(分离蛋白、清蛋白、球蛋白、醇溶蛋白、谷蛋白)的氨基酸组成结构与热特性的差异。结果:谷氨酸含量均占比最高,且含有较多带负电荷的极性氨基酸基团。莲子蛋白的E/T、E/N比值与FAO/WHO提出氨基酸比值接近,说明莲子蛋白氨基酸组成与含量均衡。电子能谱中硫元素谱图显示,清蛋白具有更高的吸收峰值,表明其他蛋白中可能含有较多的二硫键,而巯基含量较少。热特性分析表明,莲子蛋白在90℃时逐渐变性,200℃后发生玻璃化转变,内部有序结构向无序转变。其中分离蛋白、醇溶蛋白、谷蛋白的热变性温度高,可能是因为分子内部二硫键含量较高,结构紧密,且在热特性变化中重量损失更大,功能性基团改变。结论:分析不同莲子蛋白氨基酸组成、含量以及热特性的差异性,可为莲子蛋白更深入的基础性研究提供科学依据。【Objective】 The differences of amino acid composition and thermal characteristics of different lotus seed protein including isolated protein,albumin,globulin,prolamin,glutenin were studied. 【Result】 Content of glutamic acid accounted for the highest proportion and contained more negatively charged polar amino acid groups. The ratios of E/T and E/N of lotus seed protein was close to that of amino acid proposed by FAO/WHO,indicating that amino acid composition and content of lotus seed protein were balanced. The sulfur spectrum of electron spectroscopy showed that albumin had a higher absorption peak,which indicated that other proteins may contain more disulfide bonds and less sulfhydryl groups. Thermal analysis showed that lotus seed protein denatured gradually at 90 ℃,glass transition occurred after 200 ℃,and the internal ordered structure changed to disorder. Among them,the high thermal denaturation temperature of isolated protein,prolamin,glutenin may be due to the high content of disulfide bonds in the molecule,compact structure,greater weight loss,and changes of functional groups in the thermal properties. 【Conclusion】 The analysis of the differences of amino acid composition,content and thermal properties of different lotus seed protein can provide a reference for further basic research of lotus seed proteins.

关 键 词：莲子蛋白 分离蛋白 分级蛋白 氨基酸特性 热特性 

分 类 号：TS201.21[轻工技术与工程—食品科学]