低聚半乳糖糖基化法降低牛乳α_(s1)-酪蛋白抗原性和免疫原性  

Reduced Antigenicity and Immunogenicity of Bovine Milk α_(s1)-casein by Conjugation with Galactooligosaccharide

作　　者：夏薇[1] 张帆[1] 赖莹[1] 杨铮[1] 许美玉[1] 

机构地区：[1]北京林业大学生物科学与技术学院,北京100083

出　　处：《中国食物与营养》2011年第1期50-53,共4页Food and Nutrition in China

基　　金：十一五"国家科技支撑计划子课题(2006BAD04A06);教育部"留学回国人员科研启动基金

摘　　要：用等电点沉淀法从牛乳中提取酪蛋白,根据αs-酪蛋白对尿素溶液溶解特性从酪蛋白中提取αs-酪蛋白,并用阴离子交换层析使αs1-酪蛋白与αs2-酪蛋白分离。用低聚半乳糖通过在一定条件下的美拉德反应对αs1-酪蛋白进行糖基化处理,通过竞争ELISA实验检测αs1-酪蛋白糖基化产物的抗原性。结果表明,该糖基化产物的抗原抗体结合常数Kd较αs1-酪蛋白上升3.7倍,即低聚半乳糖糖基化处理使αs1-酪蛋白的抗原性得到显著降低。用动物实验和非竞争ELISA实验检测αs1-酪蛋白糖基化产物的免疫原性,结果显示免疫原性降低19%,该实验证实对降低牛乳αs1-CN抗原性和免疫原性具有显著效果,为开发较理想的、切实可行的新脱敏奶粉生产技术提供了科学依据。Casein was purified from bovine milk by the method of isoelectric precipitation,αs-casein was isolated from casein according to the character that be dissolved in urea solution and αs1-casein was separated with αs2-casein by anion-exchange chromatography.αs1-casein was conjugated with galactooligosaccharide by maillard reaction under certain conditions.Antigenicity of the conjugates was measured by competitive ELISA assay.Results showed the Kd（dissociation constant of antigen-antibody） of the conjugates was increased to 3.7 times compared with αs1-casein and antigenicity of αs1-casein was decreased significantly by conjugation with galactooligosaccharide.Results of animal experiments and noncompetitive ELISA assay indicated that the immunogeniciity of αs1-casein was reduced 19% by combining with galactooligosaccharide.Results showed that the treatments of conjugation with saccharides had significant effect on the reducing of the antigenicity and immunogenicity of bovine milk αs1-casein and provided scientific basis for developing ideal and practice desensitization production technology of milk.

关 键 词：αs1-酪蛋白 低聚半乳糖 糖基化 抗原性 免疫原性 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]