糖基化反应对大豆蛋白乳糖复合物抗原性与结构影响.pdf

现代食品科技 Modern Food Science and Technology 2015, Vol.31, No.8 糖基化反应对大豆蛋白-乳糖复合物抗原性及 结构的影响 张楠，布冠好，朱婷伟，陈复生 （河南工业大学粮油食品学院，河南郑州450001 ） 摘要：本文将乳糖通过糖基化反应引入到大豆分离蛋白(SPI)上制备大豆分离蛋白-乳糖复合物，采用间接竞争 ELISA 法测定不 同温度、不同质量比、不同反应时间下大豆分离蛋白-乳糖复合物中β-伴大豆球蛋白的抗原性变化，并对糖基化产物进行了结构特性 的研究。结果表明，糖基化能有效降低β-伴大豆球蛋白的抗原性，其抗原性从93.79%降到37.75%。糖基化改性后，大豆蛋白中游离 氨基含量降低，在反应60 h 时，游离氨基含量下降最大；傅里叶红外光谱结果表明，与原大豆分离蛋白相比，大豆分离蛋白-乳糖糖 基化产物的 α-螺旋、β-转角、无规卷曲的含量下降，而β-折叠的含量增加；SDS电泳及PAS 染色结果表明，随着糖基化反应 的程度增加，SPI 谱带逐渐的减弱，说明SPI 与乳糖分子发生了共价连接。 关键词：大豆分离蛋白；乳糖；糖基化；抗原性；结构特性 文章篇号：1673-9078(2015)8-117-121 DOI: 10.13982/j.mfst.1673-9078.2015.8.020 Effect of Glycosylation on the Antigenicity and Structural Properties of Soybean Protein Isolate-lactose Conjugate ZHANG Nan, BU Guan-hao, ZHU Ting-wei, CHEN Fu-sheng (College of Food Science and Technology, Henan University of Technology, Zhengzhou 450001, China) Abstract: Lactose was introduced into soybean protein isolate (SPI) via glycosylation to produce an SPI-lactose conjugates, under different temperatures, protein and sugar mass ratios, as well as reaction durations. Subsequent changes in the antigenicity of β-conglycinin in the SPI-lactose conjugates was estimated by indirect-competition enzyme-linked immunosorbent assay (ic-ELISA). The structural properties of the SPI-lactose conjugates were also studied. The results indicated that glycosylation reduced the antigenicity of β-conglycinin from 93.79% (control) to 37.75% (conjugates). Compared to SPI, the content of free amino groups in the complex also decreased after glycosylation. The reduction was highest at 60 hours after the of the reaction . Fourier transformed infrared spectroscopy (FT-IR