Abstract: In this study, the bioinformatics software DNAStar and Geneious and multiple reaction monitoring mass spectrometry (MRM-MS) were used to predict the linear epitope parameters, secondary structure content and epitope regions of bovine whey proteins. Meanwhile, relative quantification of linear allergenic epitopes was carried out. The results indicated that α-lactalbumin (α-LA) and β-lactoglobulin (β-LG) had 7 and 10 linear epitope regions, respectively. The secondary structure of α-LA and β-LG mainly consisted of α-helix, followed by β-turn, β-sheet and random curling, indicating that the structure of α-LA and β-LG made them more likely to become epitopes. Alkaline, protamex and flavourzyme treatment effectively reduced the linear allergenic epitopes of α-LA and β-LG by 50.0%–80.0%, with this effect being more pronounced for β-LG. The relative quantitation results showed that the content of 95.0% of linear epitope peptides was significantly reduced.

Key words: protease; enzymatic hydrolysis; whey protein; linear epitope

摘要： 以牛乳乳清蛋白为研究对象，利用DNAStar、Geneious生物软件及质谱多反应监测技术对乳清蛋白进行线性表位参数、二级结构含量和过敏表位区域预测，且对乳清蛋白线性过敏表位进行相对定量分析。结果表明：α-乳白蛋白（α-lactalbumin，α-LA）和β-乳球蛋白（β-lactoglobulin，β-LG）的线性表位区域分别有7 个和10 个；α-LA和β-LG的二级结构主要以α-螺旋为主，其次是β-转角、β-折叠和无规则卷曲，表明α-LA和β-LG的这种结构使得其成为抗原表位的可能性增大；碱性蛋白酶、复合蛋白酶和风味蛋白酶处理有效降低了α-LA和β-LG线性过敏表位，降低率为50.0%～80.0%，且3 种蛋白酶对β-LG的线性表位降解效果更加显著；通过相对定量结果发现，95.0%的线性表位肽段含量显著降低。

关键词: 蛋白酶；酶解；乳清蛋白；线性表位