苦荞蛋白的分离及其体外抗氧化活性的研究

Isolation and antioxidant activity analysis in vitro of proteins from Tartary Buckwheat

目的:提取苦荞蛋白并评价苦荞蛋白各组分的体外抗氧化能力。方法:采用不同溶剂分级提取苦荞中的清蛋白、球蛋白、醇溶蛋白和谷蛋白,并采用考马斯亮蓝蛋白定量法测定各组分的蛋白含量,SDS-PAGE电泳观察各蛋白组分的分子量分布情况;采用比色法测定各蛋白组分在体外抑制超氧阴离子自由基(O2-·)的能力和清除羟自由基(·OH)的能力。结果:清蛋白、球蛋白、醇溶蛋白和谷蛋白占总蛋白的百分含量分别为42.65%、14.08%、9.54%和33.73%,清蛋白含量最高,醇溶蛋白含量最少;各蛋白组分的分子量分布不一样;清蛋白和球蛋白均具有清除羟自由基(·OH)的能力和抑制超氧阴离子自由基(O2-·)的能力,且球蛋白高于清蛋白(p<0.05),而醇溶蛋白和谷蛋白无抗氧化能力。结论:苦荞中的清蛋白和球蛋白具有体外抗氧化能力。

Objective： Our goal was to isolate peotein fractions from Tartary Buckwheat and evaluate if protein fractions show antioxidant activity in vitro. Method： Protein fractions including albumin, globulin, prolamin and glutelin from Tartary Buckwheat were extracted and fractioned by using different solvent, and protein concentrations were determined by coomassie brilliant blue protein quantitative. SDS-PAGE electrophoresis was used to observe molecular weight of each protein fraction. Chemical colorimetric method was used to determinate the ability to remove hydroxyl radicals （.OH） and the capacity to inhibit the activity of superoxide radical （O2-.） of each protein fraction. Results： Percentage composition in albumin, globulin, prolamin and glutelin were 42.65%, 14.08%, 9.54% and 33.73% respectively, and content of albumin was the highest, prolamin was the least. The molecular weight size of each protein fraction was different. Albumin and globulin had the ability to remove hydroxyl radicals and the capacity to inhibit the activity of superoxide radical, and antioxidant ability of globulin was higher than albumin（p〈0.05）, on the contrary, prolamin and glutelin hadn＇t. Conclusion： Albumin and globulin from Tartary Buckwheat had antioxidant ability in vitro.