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Immunoglobulin (Immunoglobulin, Ig) is the most important animal blood immune factors, are mainly used to improve the body's immunity and enhanced resistance to various diseases. Which IgG is the most important antibody, IgG neutralize toxins and viruses, agglutination, activate complement cytotropic., In the humoral immune play the role of the main immune. In this study, by saturated ammonium sulfate as raw material fresh goose blood separation and extraction goose serum IgG, IgG crude extract. And then through the purification method of SephadexG-50 gel filtration chromatography and DEAE-52 anion exchange chromatography, etc., the preparation of the IgG is further purified to obtain a purity of more than 95% IgG. Finally, the stability of the IgG. Fresh goose blood as a raw material, use of salting extracted goose serum IgG were isolated IgG crude extract. By four factors and five levels based on the experimental results of the single factor quadratic orthogonal rotation combination experiment design, response surface methodology optimized extraction temperature, static time, the proportion of serum-PBS buffer solution pH factors goose serum IgG best extraction conditions: extraction temperature 35 ° C and still time 58min, 2:1 ratio of serum-PBS buffer solution (pH 7.2), IgG extracted reaches 0.681mg/mL. Reliable variance analysis and validation experiments, mathematical models and fitting better. Separation and Purification of IgG crude use of orthogonal experiment to determine the best conditions of the purified IgG experimental chromatography process parameters: the flow rate of 1.0mL/min eluent pH 7.6, into the The kind of concentration of 2.5mg/mL. The SephadexG-50, the sample desalting, and after desalting the samples were isolated and purified using DEAE-52, the last sample purity using SDS-PAGE electrophoresis, the measured sample purity was 96%, and specificity. Conducted a detailed study, the results show: greater impact heating goose stability of serum IgG, 75 ℃ heating 7min, heated to 85 ° C for 2min, denaturation rate of more than 90%, at the same heating conditions on the stability of the goose serum IgG , with the heating time, the increase in the denaturation rate; of goose serum IgG in the range of pH5.0-10.0 very stable at a pH below 5.0, denaturation increases rapidly as the pH decreased. Too acid, too alkaline will affect IgG activity; orthogonal experiment: primary and secondary order pepsin IgG denaturation rate: the pH gt; action time gt; enzyme concentration; optimum conditions for pH4.0 pepsin added 0.5mg/mL, the role of time 1h; trypsin IgG activity is relatively small, and the degeneration rate was positively correlated with the enzyme dosage and duration of action. Added protection agent in the solution is a significant protective effect on IgG activity, maltose, sorbitol, glycine size of the protective effect of IgG activity retention order: sorbitol gt; glycine gt; maltose; quadratic rotary combination of three factors experimental screening the ideal composite heat protection agent addition: 6% maltose, sorbitol 11% and glycine 0.6%. In this case, the activity of IgG retention rate was 53.2%.
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