大鲵黏液糖蛋白的提取纯化及其抗氧化性

Extraction and Purification of Mucous Glycoprotein from Giant Salamander and Its Antioxidant Activity

采用水提醇沉法提取大鲵黏液糖蛋白粗品MGP-Ⅰ,经DEAE-52和Sephadex G-100分离纯化后得糖蛋白MGP-Ⅲ,采用高效液相色谱、SDS-PAGE电泳等测定其纯度,并检测MGP-Ⅰ和MGP-Ⅲ的体外抗氧化性。结果表明:MGP-III在RID检测和UV检测中均显示单一的对称峰,峰的保留时间约为12 min。MGP-Ⅲ电泳分析泳道只有单一的染色带,分子质量约58 000 u。MGP-Ⅲ的总糖和蛋白质含量分别为61.83%和30.32%。MGP-III为单一纯品。大鲵黏液糖蛋白均具有一定的抗氧化能力,当MGP-Ⅲ的质量浓度为1.0 mg/m L时,羟自由基清除率、1,1-二苯基-2-三硝基苯肼自由基清除率、超氧阴离子自由基清除率分别为52.26%,61.45%和50.26%,高于同等条件下MGP-Ⅰ的清除率。

Crude glycoproteins（MGP-I） were obtained from Giant salamander＇s mucus through hot water extraction and ethanol precipitation. MGP-I were further purified by DEAE-52 column chromatography and Sephadex G-100 column chromatography. MGP-Ⅲwere acquired. The results showed that MGP-III was only one ingredient by using HPLC analytical method, and SDS-PAGE electrophoresis analytical method. The antioxidant activity of MGP-I and MGP-III were determined, too. By using the RID test and UV test, it showed only one single and symmetry peak, and had the same retention time about 12 min of the peak; It was only one single dyeing belt, and the molecular weight was about 58 000 u; The physical and chemical analysis of MGP-III showed that the total sugar content was 61.83% and protein content was 30.32%. It was proved that MGP-III was only one ingredient. Both MGP-I and MGP-III had antioxidant capacity,and MGP-III was higher than MGP-I. When MGP-III＇s concentration was 1.0 mg/m L, the hydroxyl free radical clearance rate was 52.26%, DPPH free radical clearance rate was 61.45%, superoxide anion radical clearance rate was 50.26%respectively.