聚乙二醇沉淀蛋清蛋白质的规律及在卵白蛋白分离中的应用  

Protein Precipitation from Egg White with Polyethylene Glycol and Its Application for Ovalbumin Separation

作　　者：闻崇炜[1] 赵烨清 石莉[1] 欧阳臻[1] WEN Chongwei;ZHAO Yeqing;SHI Li;OUYANG Zhen(School of Pharmacy, Jiangsu University, Zhenjiang 212013, China)

机构地区：[1]江苏大学药学院,江苏镇江212013

出　　处：《食品科学》2018年第1期29-35,共7页Food Science

基　　金：国家自然科学基金面上项目(81573529);江苏省普通高校研究生实践创新计划项目(SJLX15_0512)

摘　　要：研究3种pH值条件下4种聚乙二醇(polyethylene glycol,PEG)对卵白蛋白(ovalbumin,OVA)、卵转铁蛋白(ovotransferrin,OVT)与溶菌酶(lysozyme,LYZ)的沉淀效率,根据变化规律建立无需后续脱盐的OVA分离新工艺。结果表明:PEG 4000、6000、8000及10000均可有效沉淀OVA、OVT及LYZ,沉淀率受PEG质量分数及pH值影响。其中pH 7.5、PEG 4000质量分数12%时,OVA、OVT及LYZ的沉淀率相差最大,当pH值从7.5调至5.5时,3种蛋白质沉淀率的变化幅度相差也最大。由此建立如下分离工艺:首先向pH 7.5的蛋清液中加PEG 4000至质量分数为12%,离心收集上清液,即得纯度88.1%的OVA,提取率为95.1%;再将所得上清液pH值调至5.5,离心收集上清液,所得OVA纯度提高至99.7%,提取率为87.3%。该工艺简便易行,有利于OVA的大规模制备及在食品及医药领域的应用。This work was carried out to investigate the effect of polyethylene glycol （PEG） molecular weight, PEG dosage and pH value of egg white on the precipitation rate of ovalbumin （OVA）, ovotransferrin （OVT） and lysozyme （LYZ）, and further to establish a new procedure for the separation of OVA from egg white. It was found that OVA, OVT and LYZ could be precipitated by PEG 4000, 6000, 8000 or 10000. In addition, the precipitation rate of OVA, OVT and LYZ was signi？cantly in？uenced by PEG dosage and pH. By addition of 12% PEG and at pH 7.5, the maximum difference between the precipitation rates of OVA, OVT and LYZ was observed. This result was also obtained when pH was adjusted to 5.5. Therefore, OVA could be produced by the following procedure. PEG 4000 was added into egg white （pH 7.5） until its concentration reached 12%, and then the supernatant was collected after centrifugation as OVA with a recovery of 95.1% and a purity of 88.1%. The purity was increased to 99.7%, while the recovery was decreased to 87.3% by adjusting the pH to 5.5 and collecting centrifugal supernatant. This puri？cation procedure was simple and easy to operate and could facilitate large-scale production and application of OVA in food and medicinal fields.

关 键 词：聚乙二醇沉淀 相对分子质量 卵白蛋白 卵转铁蛋白 溶菌酶 

分 类 号：TS253.4[轻工技术与工程—农产品加工及贮藏工程] Q503[轻工技术与工程—食品科学与工程]