三种多酚对羟自由基氧化花生球蛋白的影响

Effects of three polyphenols on hydroxyl radical oxidation of arachin

为探究3种多酚对羟自由基氧化花生球蛋白的干预作用,通过建立羟自由基氧化体系,采用不同浓度梯度的儿茶素、绿原酸、杨梅素进行干预,分析花生球蛋白的羰基、游离氨基、浊度、紫外可见、荧光光谱及二级结构等变化规律。结果表明,不同浓度的3种多酚对羟自由基氧化花生球蛋白均有一定的抑制作用,其中13.33μmol/g的儿茶素可使羟自由基氧化花生球蛋白的羰基含量下降22.55%,内源荧光最大波长发生红移,66.67μmol/g的儿茶素使游离氨基上升32.08%,二级结构中无规则卷曲含量下降;杨梅素可使花生球蛋白浊度降低68.63%;绿原酸使蛋白的α-螺旋含量和最大紫外吸光值上升。综上,3种多酚的干预可减少或缓解羟自由基对花生球蛋白的氧化损伤,进而影响其结构和性质,其中儿茶素的氧化抑制效果最好。该研究可为花生蛋白的氧化研究和进一步加工利用提供科学依据。

To clarify the effect of three polyphenols on oxidized arachin,a simulation system of hydroxyl free radical oxidation was established,and then the intervention of catechin(C),chlorogenic acid(CA),and myricetin(M)with different concentrations on indicators of oxidized arachin,such as carbonyl and free amino group,turbidity,ultraviolet-visible(UV-vis),fluorescence spectrum,and secondary structure were analyzed.Results showed that all three polyphenols with different concentrations had certain inhibitory effects on hydroxyl radical oxidation of arachin,among them,the carbonyl content of oxidized arachin reduced was by 22.55%with the addition of 13.33μmol/g C,and a redshift of the maximum wavelength of endogenous fluorescence was observed.The free amino group increased by 32.08%after the addition of 66.67μmol/g C,and the random coil content diminished in the secondary structure.The turbidity of oxidized arachin reduced by 68.63%after the addition of M,while theα-helix content rosed in the secondary structure by the addition of CA,meanwhile,an increase in the maximal UV absorption was also observed.To sum up,the intervention of the three polyphenols could reduce or remission the oxidative damage of arachin caused by hydroxyl radical,and then affect its structure and properties,among which C showed the best oxidative inhibition.This study could provide a scientific basis for oxidation research and further processing and utilization of peanut protein.