【摘要】 [目的]研究采用木瓜蛋白酶水解核桃蛋白的工艺条件及水解物的抗氧化活性。[方法]采用正交试验法确定木瓜蛋白酶水解核桃蛋白的最适工艺条件,采用Sephadex G-25凝胶色谱分离酶水解物,通过测定羟自由基(OH.)和超氧阴离子自由基清除能力研究了酶水解物的抗氧化活性。[结果]核桃蛋白木瓜蛋白酶水解的最优条件是温度55℃,底物浓度4%,酶浓度60 000 U/g,pH值8.0;在水解度达到38.4%时,其酶解产物对羟自由基(OH.)和超氧阴离子自由基(O2.)的清除率分别为22.5%和46.4%。采用Sephadex G-25凝胶柱层析对水解度38.4%的酶水解物进行分离得到了A、B、C和D4个肽片段,其中肽片段C的自由基清除能力最大。[结论]核桃蛋白木瓜蛋白酶水解物具有一定抗氧化活性。更多还原

【Abstract】 [Objective] The research aimed to investigate the optimum technological conditions of walnut protein hydrolyzed by papain and antioxidative activity of its hydrolysate.[Method] The optimum technological conditions of walnut protein hydrolyzed by papain were confirmed by orthogonal experiment.The enzyme hydrolysate was separated by Sephadex G-25 gel filtration and the antioxidative activities of hydrolysate were studied through determining the scavenging activities of hydroxyl and superoxide anion free radicals.[Result] The optimum conditions for the papain hydrolysis of walnut protein were as follows: the temperature of 55 ℃,substrate concentration of 5%,enzyme concentration of 60 000 U/g and pH of 8.0.When the hydrolysis degree was 38.4%,the scavenging rate of its enzymolysis products to hydroxyl free radicals superoxide anion free radicals were 22.5% and 46.4% respectively.Four fractional peptides were obtained from hydrolysate by Sephadex G-25 gel filtration.Among them,the scavenging capability of the peptide C was the biggest.[Conclusion] The papain hydrolysate of walnut protein had certain antioxidative activity.更多还原