牡蛎蛋白源钙离子螯合肽的制备与性质分析

Preparation and Characterization of Oyster Protein-derived Calcium-chelating Peptides

牡蛎是我国重要的养殖贝类之一,其含有大量蛋白质。因此,以牡蛎作为蛋白来源开发生物活性肽具有重要研究价值。基于前期试验结果,以水解度和螯合率为指标,通过水解试验,筛选出风味蛋白酶作为最适于制备牡蛎蛋白源钙离子螯合肽的蛋白酶。随后,通过单因素试验优化了使用风味蛋白酶水解牡蛎蛋白制备钙离子螯合肽的方法,结果表明,当底物质量分数为6%,酶/底物(E/S)比为1∶66.7时,在温度50℃,pH值7.0条件下水解4 h,钙离子螯合率达到38.98%,水解度达到43.6%。通过高效液相排阻色谱法测定了钙离子螯合肽的分子量分布,结果表明,绝大部分牡蛎肽的分子量分布范围在1 kDa以下,表明水解后所获得的多肽以八肽或更小的多肽为主。通过DPPH自由基清除试验显示1 mg/mL的钙离子螯合肽的DPPH自由基清除率达到33.5%,所制备的牡蛎蛋白源钙离子螯合肽不仅可以作为钙补充剂使用,同时还具有一定的抗氧化作用,具有良好的应用价值。

Oyster is one of the important shellfish cultured in China,and it contains a lot of protein.Therefore,the development of biologically active peptides from oyster proteins has important research value.In this paper,based on the results of previous experiments,using the degree of hydrolysis and chelation rate as indicators,through hydrolysis experiments,the flavourzyme was screened out as the most suitable protease for preparing the calcium-chelating peptide from oyster proteins.Subsequently,the method of preparing calcium ion chelating peptides from oyster protein using flavourzyme was studied through single factor experiments.The results showed that when the substrate concentration was 6%and the enzyme/substrate(E/S)ratio was 1∶66.7,the calcium ion chelation rate reached 38.98%,and the degree of hydrolysis reached 43.6%by hydrolyzing the proteins for 4 h at a temperature of 50℃and at pH 7.0.The molecular weight distribution of the calcium-chelating peptides prepared was determined by high performance liquid exclusion chromatography.The results showed that the molecular weight distribution of most oyster peptides was below 1 kDa,indicating that the peptides obtained after hydrolysis were octapeptides or smaller.Mainly.the DPPH free radical scavenging experiment showed that the 1 mg/mL calcium chelating peptide had a DPPH free radical scavenging rate of 33.5%,indicating that the oyster protein-derived calcium-chelating peptides prepared in this study can not only be used as a calcium supplement,but also has a certain antioxidant effect,showing promising application value in food industry.