富硒糙米蛋白理化特性及抗氧化活性的研究

Physicochemical Properties and Antioxidant Activity of Protein in Selenium-enriched Brown Rice

本文以三种富硒糙米为原料,对糙米中蛋白的理化特性和富硒糙米蛋白的抗氧化活性进行分析与测定。研究发现:相较于普通糙米,富硒糙米中硒含量显著增加(P<0.05);富硒处理可提高糙米中粗蛋白含量,造成肉豆蔻酸含量降低,硬脂酸含量升高;相较于普通糙米蛋白,富硒糙米蛋白中蛋氨酸含量上升,半胱氨酸含量下降;富硒处理对蛋白质分子量及亚基组成无显著影响,但会增加β-折叠、无规则卷含量增加,降低β-转角、α-螺旋含量。富硒糙米蛋白具一定的DPPH自由基、羟自由基清除能力与还原力,且均明显高于普通糙米蛋白,表现出较强的体外抗氧化活性。

Three kinds of selenium-enriched brown rice were used as raw materials to analyze the physicochemical properties of brown rice and protein and the antioxidant activity of selenium-enriched brown rice protein.The research results demonstrated that the contents of selenium in selenium-enriched brown rice increased significantly compared with ordinary brown rice(P<0.05).Selenium-enriched treatment could increase the contents of crude protein in brown rice,decrease myristic acid contents and increase stearic acid contents.Compared with ordinary brown rice protein,the contents of methionine in seleniumenriched brown rice protein was increased,while cysteine contents was decreased significantly.Selenium-rich treatment had no significant effect on the molecular weight and subunit of the protein,but it could increaseβ-sheet,unordered contents,reduceβ-turns,α-helix contents.The selenium-enriched brown rice protein had strong DPPH free radical,hydroxyl radical scavenging ability and reducing power,which were significantly higher than that of ordinary brown rice protein showed strong in vitro antioxidant activity.