醇析法结合离子交换法提取分离卵转铁蛋白

Isolation of Ovotransferrin by Combination of Ethanol Extraction and Cation-exchange Chromatography

乙醇析出法结合两步弱酸性阳离子交换层析可有效地从鸡蛋清中分离纯化卵转铁蛋白,结果表明:预处理后黏度降低的蛋清经两步醇析法(45%浓度乙醇沉淀杂蛋白、59%乙醇浓度沉淀获得OVT粗品),再经两步阳离子层析法(第一步:pH8.0,20 mmol/L磷酸盐缓冲液平衡,含0.5 mol/L NaCl的pH8.0,20 mmol/L磷酸盐缓冲液洗脱;第二步:pH5.2,10 mmol/L柠檬酸盐缓冲液平衡,含0.5 mol/L NaCl的pH5.2,10 mmol/L柠檬酸盐缓冲液洗脱)可得到纯度较高的卵转铁蛋白;SDS-PAGE电泳检测终产品的纯度大于96%。

Ethanol extraction and weak acidous cation-exchange chromatography were combined to isolate and purify ovotransferrin from hen-egg white. Results showed that ovotransferrin of higher purity could be obtained from pretreated hen-egg white with lower viscosity by combining 2 steps of ethanol extraction （removing other protein by 45 % ethanol precipitation, and recovering ovotransferrin crude by 59 % ethanol） and 2 steps of cation-exchange chromatography （the first step： starting buffer： pH8.0,20 mmol/L phosphate buffer, elution buffer： starting buffer with 0.5 mol/L NaCl; the second step： pH5.2,10 mmol/L citrate buffer as starting buffer, and starting buffer with 0.5 mol/L NaCl as elution buffer）; Evaluation results from SDS-PAGE electrophoresis revealed that the purity of final product was no less than 96 %.