[关键词]
[摘要]
大豆是优质的植物蛋白资源,同时也是八大食物过敏原之一;糖基化改性是降低蛋白质过敏原的有效方法之一。本文以大豆分离蛋白和葡萄糖为原料,在蛋白与糖不同质量比、不同温度、不同时间条件下进行美拉德反应,制取糖基化复合物;并以β-伴大豆球蛋白抗原抑制率为指标,采用间接竞争ELISA方法检测糖基化复合物抗原性的变化。发现在温度55 ℃、蛋白与糖比例为3:1时,制备的糖基化复合物抗原性较低;当反应时间为72 h时,抗原抑制率从93.54%降低到22.58%。同时,通过三硝基苯磺酸(TNBS)法、十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)证明了美拉德反应的发生;紫外光扫描、傅里叶红外光谱分析等方法研究了蛋白质结构的变化。这些基础研究可能为探究糖基化修饰对抗原性影响的作用机理、开发低敏性大豆蛋白制品提供研究方法和理论依据。
[Key word]
[Abstract]
Soybean is a high-quality protein source and one of eight major food allergens. Glycation is an effective way to remove protein allergens. In this paper, soy protein isolate (SPI) and glucose were used as raw materials for Maillard reactions, which were performed with various protein to carbohydrate ratios, temperatures, and experimental time, to prepare glycated conjugates. The inhibition of antigen β-conglycinin in SPI-glucose conjugates was used as an indicator, and indirect competitive enzyme-linked immunosorbent assay (ELISA) was employed to measure the antigenicity of glycated conjugates. When the mass ratio of protein to sugar was 3:1 at a temperature of 55 , the antigenicity of the prepared glycated conjugates was relatively low. When the reaction time was 72 h, the inhibition rate of antigen β-conglycinin decreased from 93.54% to 22.58%. The Maillard reaction was confirmed by the trinitrobenzene sulfonic acid (TNBS) method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Changes in protein structure were studied by ultraviolet scans and Fourier transform infrared spectroscopy (FTIR). These basic studies might provide research methods and a theoretical basis for determining the mechanism mediating the effect of glycation on antigenicity and developing soy protein products with low allergen contents.
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[基金项目]
国家自然科学基金项目(31201293,21176058,31171790);国家863项目(2013AA102208-5);河南省教育厅科学技术研究重点项目(14B550013)