河套小麦胚芽源多肽的抗氧化活性研究

Study on the Antioxidant Activity Hetao Wheat Germ Polypeptides

利用中性蛋白酶、胰蛋白酶、胃蛋白酶等酶解河套小麦胚芽蛋白获得多肽,测定其体外抗氧化能力,利用聚丙烯酰胺凝胶电泳(SDS-PAGE)确定其多肽分布。结果表明,胚芽蛋白及多肽浓度与抗氧化能力呈正相关。不同浓度的中性蛋白酶酶解获得的多肽的抗氧化能力显著高于胃蛋白酶和胰蛋白酶酶解获得的多肽(P<0.05),其还原能力、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS^(+))和1,1-二苯基-2-苦基苯肼(DPPH)清除率最高达(1.17±0.004)1.0 mg/mL、(84.82%±0.87%)1.5 mg/mL和(55.01%±0.01%)1.0 mg/mL,且其ABTS^(+)和DPPH自由基清除率均显著高于胚芽蛋白(P<0.05)。另外,不同蛋白酶水解能力不同,其中胃蛋白酶的水解能力最大,中性蛋白酶水解能力最小;胚芽蛋白多肽的抗氧化能力与其分子量大小相关,但不一定蛋白多肽的分子量越小,其抗氧化效果越好。上述结果为进一步研究河套小麦胚芽抗氧化肽提供了一定的参考依据。

In this experiment,the peptides were obtained by enzymatic digestion of wheat germ proteins from river sets using neutral protease,trypsin and pepsin.In vitro antioxidant capacity of samples was determined and their polypeptides distribution was determined using polyacrylamide gel electrophoresis(SDS-PAGE).The results showed that germ protein and polypeptides concentrations were positively correlated with antioxidant capacity.The antioxidant capacity of the peptides obtained by enzymatic digestion of neutral protease at different concentrations was significantly higher than that obtained by enzymatic digestion of pepsin and trypsin(P<0.05),and their reducing capacity,2,2-biazo-bis(3-ethyl-benzothiazole-6-sulfonic acid)diammonium salt(ABTS^(+)),1,1-diphenyl-2-picrylhydrazyl(DPPH)clearance was up to(1.17±0.004)1.0 mg/mL,(84.82%±0.87%)1.5 mg/mL and(55.01%±0.01%)1.0 mg/mL,respectivety,and their ABTS^(+)and DPPH radical scavenging rates were significantly higher than those of germ proteins(p<0.05).In addition,for the hydrolysis capacity of different proteases differs,pepsin had the greatest hydrolysis capacity while neutral protease had the least.The antioxidant capacity of germ protein polypeptides correlated with their molecular weight,but it is not necessarily the case that the smaller the molecular weight of a protein peptide had the better antioxidant effect.The results of these experiments provide a theoretical basis for further research on the antioxidant polypeptides of wheat germ in the Hetao.