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碱性蛋白酶水解麦胚所获得的肽类混合物有较高的生物活性.采用超滤法对麦胚肽进行分离,对不同分子质量区间的小肽进行抗过敏活性研究.结果表明,分离麦胚肽的最佳超滤工艺条件为:操作压力为0.4 MPa,料液质量浓度为16 mg/mL(10 ku扣5 ku膜)或20 mg/mL(1 ku 膜),周期为lh;麦胚酶解液经全质谱鉴定,主要为5 107种不同种类的肽段,建立了简易麦胚肽数据库;麦胚肽体外抗过敏活性结果表明,其抗过敏活性与小肽的分子质量大小呈负相关,分子质量小于l ku的组分表现出最大的透明质酸酶抑制率,达到82.5％,IC50约为0.87 mg/mL.生物信息学技术结合质谱分析麦胚肽抗过敏活性位点可能为麦胚肽C端的甘氨酸结构域,通过调节Th2细胞的分化异常和改变靶细胞细胞膜通透性来实现麦胚肽的抗过敏功能.“,”Active peptide is a kind of amino acid sequence with special physiological activity,of which the number of amino acids is generally less than 20,molecular weight of 6 000 u or less,and the key factor determine its activity is the type of amino acids and their arrangement.The peptide mixture obtained by alkaline protease hydrolysis of wheat germ has high biological activity.The wheat germ peptides were separated and enriched by ultra-filtration method in this study,and the anti-allergic activity and structure-function relationship of these peptides fragments were analyzed.The result showed that the optimized ultra-filtration conditions of separating the wheat germ peptides were as follows:time of 1 h,pressure of 0.4 MPa,temperature of 25 ℃ and the filtrate concentration of 16 mg/mL (10 ku and 5 ku) or 20 mg/mL (1 ku).After ultra-filtration,the constituents were identified by mass spectrometry,which revealed that 5 170 kinds of different peptide fragments were included accounting for more than 72％.Meanwhile,the simple database of the peptides of wheat germ was set up.The result of the anti-allergic activity demonstrated that the ant-allergic activity of these peptides fragments had negative correlation with the molecular weight.These fragments with molecular weight less than 1 ku had the highest inhibition ratio of 82.5％,while the IC5o was 0.87 mg/mL.C-terminal glycine structural domain of small peptide was proved to be the active site of anti-anaphylaxis by bioinformatics techniques combined with mass spectrometry analysis.The anti-anaphylaxis of wheat germ peptides was realized by regulating of the prosoplasia of the Th2 cell and changing the membrane permeability of target cell.This study will not only provide a considerable measure to separate wheat germ peptides for food industry but also supply the reference for the development of functional health food and pharmaceutical raw materials.