【作者】 张雪梅；

【导师】 郭顺堂；

【作者基本信息】 中国农业大学 ， 食品科学， 2003， 硕士

【摘要】 从二十世纪七十年代以来，大豆肽就逐渐成为蛋白质研究和利用领域的热点之一。研究发现大豆肽具有降胆固醇、抗氧化、降血压、减肥、抗疲劳等生理功能，但对于大豆糖肽生理活性的研究至今尚未见报道。本论文以大豆糖蛋白——β-伴大豆球蛋白为底物，用酶法制备大豆糖肽，通过细胞培养的方法研究糖肽对小鼠脾细胞增殖的影响作用，并探讨糖链在此功能中所起的作用。 利用Alcalase和Pronase E酶解分别制备大豆肽，肽产物经过Sephadex G-25凝胶过滤分组，通过糖在各组分中的分布及薄板层析对含糖的肽组分是否是糖肽进行鉴定。所得糖肽经过糖苷酶(N-Glycosidase F)酶解后，利用Sephadex G-25凝胶过滤获得去除糖链后的肽组分。利用MTS／PMS比色法测定糖肽对小鼠脾细胞增殖的作用效果。 研究结果表明，以β-伴大豆球蛋白为底物分别经Alcalase和Pronase E酶解，分离出两种平均分子量为1670Da和1135Da的糖肽，含糖量分别为8.23％和9.66％。这两种糖肽对ConA诱导的脾细胞增殖有抑制作用，而且在浓度为50-100μg／ml时抑制效果显著，能抑制ConA诱导活性的40～50％。当用N-Glycosidase F去除两种糖肽中的糖链后，Alcalase酶解物中的糖肽抑制活性减弱，而Pronase E酶解物中的糖肽活性不受影响。另一方面，在无ConA存在的条件下，两种大豆糖肽对脾细胞表现出增殖促进作用。以上结果说明大豆糖肽对免疫功能有双向调节的作用。更多还原

【Abstract】 Soy peptides have been one of focuses in the research and utility of protein since 1970s. Studies showed that soy peptides have many biological functions, such as hypocholesterol activity, antioxidativity, hypotensive activity, control of obesity and fatigue and so on. But there is no report about the biological activity of soy glycopeptides. The objective of the study was to obtain soy glycopeptides from -conglycinin hydrolydates and to confirm effects of glycopeptides on the proliferation of murine splenocytes by the method of cell incubation in vitro. In addition, the role of carbohydrate chains in the effect was also investigated.Alcalase and Pronase E were used to hydrolyze -conglycinin to prepare soy peptides. After isolated from soy peptides by Sephadex G-25, carbohydrate-containing peptides were pooled, and identified the carbohydrate-peptide linkage by thin-layer chromatography. Soy glycopeptides were treated with N-Glycosidase F and then applied to Sephadex G-25 to obtain peptides without carbohydrate. MTS/PMS colorimetric assay was used to determine the proliferation of murine splenocytes, in which absorbance at 492nm was consistent with the number of cells.In the study two kinds of soy glycopeptides were isolated from hydrolysates, with average molecular weight of 1670Da and 1135Da. The carbohydrate content of two glycopeptides was 8.23% and 9.66% respectively. Both of soy glycopeptides had inhibitory effects on ConA-stimulated proliferation of murine splenocytes. The degree of inhibitory effect on ConA-stimulated activity reached to 40%~50% at concentration ranging from 50~100pg/ml. When carbohydrate chains in glycopeptides were removed with N-Glycosidase F, the inhibitory effect of glycopeptide derived from Alcalase hydrolysate decreased, but that of glycopeptide from Pronase E hydrolysate changed little. On the other hand, both of glycopeptides showed promoting effects on proliferation of murine splenocytes in the absence of ConA. The results showed that soy glycopeptides have immunomodulatory effect from two aspects.更多还原