大麦醇溶蛋白的提取及TGase催化糖基化改性
摘 要以大麦籽粒为原料，根据Obsorne法提取籽粒中的醇溶蛋白，探讨了不同乙醇体积分数对大麦醇溶蛋白提取率以及纯度的影响，并测量其持水性及持油性。在转谷氨酰胺酶的（transglutaminase，TGase）催化作用下，壳寡糖(chitosan oligosaccharide/ chitooligosac-charide, COS)与大麦醇溶蛋白进行糖基化反应，使蛋白样品改性。以大麦醇溶蛋白糖基化修饰产物中单糖的导入量为指标优化糖基化交联反应，用SDS-聚丙烯酰胺凝胶电泳确认单糖的导入情况，并表征了其溶解性。实验结果表明，体积分数为55%的乙醇能更好地提取大麦醇溶蛋白，其提取率为7。47%，蛋白浓度为84。19%，提取出的蛋白样品持油性较好，但持水性较弱。其糖基化实验中，最佳反应体系为：底物浓度4%，大麦醇溶蛋白中酰基供体与壳寡糖中酰基受体物质的量比为1:4，PH为8。0，TGase活力为10U/g，反应温度为37℃，反应时长为3h。其糖基化修饰产物溶解性有明显改善。88777
Obsorne method is used to extract hordein。 In this paper, the effects of different ethanol volume fraction on the extraction rate and purity of hordein from barley grain were studied, and its water holding capacity and oil holding capacity were measured。 The TGase catalyzes glycosylation of barley hordein with COS。 The introduction of monosaccharide in the modified product of barley hordein was optimized。 The introduction of mono-sugar was confirmed by SDS-polyacrylamide gel electrophoresis, and its solubility was characterized。 55% ethanol could better extract barley hordein, the extraction rate is 7。47%, the protein concentration is 84。19%, and its oil holding capacity is good, but the water holding capacity is weak。 In the glycosylation experiment, the optimum reaction system was as follows: the substrate concentration is 4%, the ratio of the acyl donor to the acyl acceptor in the COS is 1: 4, the pH is 8。0, the activity of TGase is 10U / g, the reaction temperature is 37 ℃, the reaction time is 3h。 Its glycosylation modified product solubility significantly improved。
毕业论文关键词：大麦醇溶蛋白； 提取； 转谷氨酰胺酶； 壳寡糖； 糖基化改性
Key words: Hordein; Extraction; TGase; COS; Glycosylation modification
目录 3
引言 4
1。 材料与方法 4
1。1 材料与源Q于D优G尔X论V文Y网wwW.yOueRw.com 原文+QQ75201`8766 试剂 4
1。2 方法 4
1。2。1 大麦醇溶蛋白的提取 4
1。2。2 蛋白质含量的测定 5
1。2。3 持水性WHC 5
1。2。4 持油性OHC 5
1。2。5 糖基化修饰产物的制备 5
1。2。6 DNS法测修饰产物中单糖导入量 6
1。2。7 SDS-PAGE确认大麦醇溶蛋白与氨基葡萄糖发生交联反应 6
1。2。8溶解性测定 6
2。 结果与分析 6
2。1 乙醇体积分数对提取大麦醇溶蛋白的影响 6
2。2 持水性WHC和持油性OHC 7
2。3 对大麦醇溶蛋白糖基化修饰反应的影响 7
2。3。1 底物浓度对大麦醇溶蛋白糖基化修饰反应的影响