摘要
为探明乳清蛋白抗氧化肽结构功能关系,利用大孔吸附树脂、超滤离心以及凝胶过滤色谱等手段纯化乳清蛋白抗氧化肽组分,检测分离组分的抗氧化活性、分子质量分布及氨基酸组成,并分析抗氧化肽的构效关系。结果表明,在洗脱液为65%乙醇,流速1 mL/min,样品浓度10 mg/mL时大孔树脂脱盐效果最佳,蛋白回收率为74.77%。经超滤离心后小于3 ku的组分B-3抗氧化活性较强,DPPH自由基清除率为17.52%。B-3经凝胶色谱Sephadex G-25+G-50串联分离最终得到抗氧化活性最高的组分B-3-3。B-3-3的分子质量最小,主要分布在1 ku以下,小肽(2~8肽)占比为88.53%,其DPPH自由基清除率提高到24.07%,自由巯基含量为116.47 nmol/mg,总巯基含量为167.38 nmol/mg,疏水性氨基酸和抗氧化性氨基酸占比分别为43.36%、28.01%。结果表明,乳清蛋白抗氧化肽的巯基含量与自由基清除率呈正相关,同时抗氧化肽段分子质量越小,抗氧化活性越高。
The aim of this study was to investigate the structure-function relationship of whey protein antioxidant peptides.Purification was achieved using macroporous resin,ultrafiltration,and gel chromatography.The antioxidant activity,molecular weight distribution,and amino acid composition of the isolated fractions were determined,and the correlations were analyzed.The results showed that the best desalination of the macroporous resin was achieved at an eluent of 65%ethanol,flow rate of 1 mL/min,and sample concentration of 10 mg/mL,with a protein recovery of 74.77%.B-3 with a molecular weight of less than 3 ku is more active after ultrafiltration,the DPPH radical scavenging rate was 17.52%.B-3-3 is the highest antioxidant activity component,which was obtained by Sephadex G-25/G-50 gel chromatography by B-3.It has the smallest molecular weight,and is mainly distributed below 1 ku,with 88.53%of 2~8 peptides,and the DPPH radicals scavenging rate was up to 24.07%,with free thiol content of 116.47 nmol/mg,total thiol content of 167.38 nmol/mg,and the percentage of hydrophobic amino acids and antioxidant amino acids respectively were 43.36%and 28.01%.It was shown that the thiol content of antioxidant peptides from whey protein was positively correlated with the free radical scavenging rate,while the smaller the molecular weight of the antioxidant peptide segment,the higher the antioxidant activity.
作者
罕璐
肖富权
郝刚
毕秀芳
黄梅桂
HAN Lu;XIAO Fuquan;HAO Gang;BI Xiufang;HUANG Meigui(College of Food Science and Technology,Southwest Minzu University,Chengdu 610041,China)
出处
《中国乳品工业》
北大核心
2025年第8期32-38,共7页
China Dairy Industry
基金
西南民族大学研究生创新型科研项目(ZD2023072)。
关键词
乳清蛋白
抗氧化肽
分离纯化
分子质量分布
whey protein
antioxidant peptide
separation and purification
molecular weight distribution
