玉米醇溶蛋白水解物的Zn2+螯合能力及抗氧化活性分析

Analysis of Zinc-chelating Ability and Antioxidant Activity of Zein Hydrolysate

为了提高玉米醇溶蛋白在食品中的应用,以玉米醇溶蛋白为原料,以锌螯合能力为指标,在pH为12的条件下,通过单因素实验确定蛋白酶K水解玉米醇溶蛋白的最适反应条件,并分析玉米醇溶蛋白锌离子螯合物的抗氧化活性。在底物浓度10 mg·mL^-1、酶添加量2.4 U·mg^-1、反应温度60℃、反应时间2 h条件下,玉米醇溶蛋白水解物锌离子螯合能力最强,达到12.16 mg·g^-1玉米醇溶蛋白,所对应水解度为4.10%;抗氧化实验结果显示:玉米醇溶蛋白水解物锌离子螯合物有显著的清除DPPH自由基、羟自由基、ABTS^+·的能力,清除效果显著优于未水解的玉米醇溶蛋白,且与玉米醇溶蛋白水解物锌离子螯合物浓度呈正相关,为玉米醇溶蛋白应用于新型膳食补充剂提供广阔的前景。

Using zein as raw material,zinc chelating ability as index,the optimal conditions of zein hydrolysis by proteinase K were determined through single factor experiment at pH 12,and the antioxidant activity of product of zinc-chelating of zein was analyzed at the same time.When the reaction time was 2 h,the substrate concentration was 10 mg·mL-1,the enzyme content was 2.4 U·mL^-1,the reaction temperature was 60℃,zinc ion chelating ability of zein hydrolysate reached to 12.16 mg·g^-1 zein,the corresponding hydrolysis degree was 4.10%.The results of antioxidation experiments showed that zinc-chelating ability on zein hydrolysate had better scavenging activity against DPPH,hydroxyl radicals,and ABTS^+·than that of zein,and it was positively correlated to a concentration-dependent manner.Zein could be used as a kind of new dietary supplement.