Studies On Fractionation And Extraction And Stability Of Immunoglobulin G From Goose Blood

Immunoglobulin is most eye-catching animal blood immune factors, mainly used to improve the body's immunity, strengthen the resistance to various diseases. Which IgG is the most important antibodies, IgG has funtions with neutralizing toxins and viruses,aggregation,activation of complement,pro-cell, ect, IgG play a"main immunity"effect in humoral immunity. In this study, IgG was isolated from fresh goose seum by the neuter salt methods using saturated ammonium sulphate, and then got the crude extraction of IgG. And after further purified with sephadex G-50 gel filtration chromatography methods, and DEAE-52 chromatography methods, and then got then most purified extraction of IgG was over 95%, the study on the stability of goose blood IgG.Took fresh goose blood as the raw material , In this article, the IgG was isolated from goose serum by the neuter salt methods using saturated ammonium sulphate, and the crude extraction then was got. Based on the results of single-factor experiments, using the method of orthogonal rotation combination test design method to four factors and five levels, the extraction method of IgG from goose serum was studied. Factors of extracting temperature, time of digestion, mixing serum and pbs and buffer solution for pH were optimized with Response Surface analytical meted. The optimal parameters of extracting technology were as follow: extracting temperature was 35℃, time of digestion 60min, mixing serum and PBS at 2:1 and buffer solution for pH 7.2 and the extraction rate of IgG reached 0.681mg/mL. Through the variance analysis and verification test, it was showed that mathematical model was reliable and the fitting of the model was better.The study of crude IgG purification process condition. Determine the optimum conditions for chromatography purification IgG by orthogonality experiment. The optimized process parameters were: flow rate-1.0mL/min, the eluent pH7.6, sample injection density 2.5mg/mL. Remove ammonium sulfate from protein sample by sephadexG-50, and the purified by DEAE-52 chromatogram, the purity of IgG was identified by SDS-PAGE and the purity of IgG was 96%. and specificity.The paper firstly studied of IgG stability. The results showed that the IgG stability was greatly influenced by heat, when heats up Time at 75℃or 2 min at 85℃, the denaturizing rate of IgG reached 90%. At the same condition of heating, the denaturizing rate increased with the prolong of heating time; IgG is quite stable with the range of pH5.0-pH10.0, when pH value below 5.0, the denaturizing rate of IgG went up sharply with the decrease of pH value, too acid, too alkaline will affect the activity of IgG; Through the orthogonal test, the order of factors which the pepsin affected the activity of IgG was: pH>action. time>enzyme concentration. The best condition was A3B2C1, that was: pH was 4.0, the pepsin concentration was 0.5mg/mL, action time was 1h, the influence to the IgG of the trypsin was relative small. and the degeneration rate and the enzyme dosage and the role of time-dependent.Add the protection agent in the solution have protecting effect obvious to the IgG activity. Maltose and Sorbitol and Glycin, The order of their contribution to the active IgG residues are: Sorbitol>Glycin>Maltose. The better compound thermal protectent by orthogonal rotatable central composite design were Maltose6%, Sorbitol11%, Glycin0.6%. rentention rate of activity IgG is 53.2%.