Study On The Extraction And Purifucation Of Immunoglobulin G From Yak Blood

Fresh yak blood was used as the materials. Saturated ammonium sulfate method extraction, low temperature absolute ethyl alcohol precipitation method extraction and caprylic acid-ammonium sulfate method extraction was used to extract IgG from Yak blood. The orthogonal test parameters were determined by single factor in different conditions of the extraction. The optimum conditions of extraction were studied. IgG of three extraction methods will be compared to choose the best way to a kind of extraction efficiency. And then the yak blood IgG purification and determination carried out by ion exchange and electrophoresis. The results showed that:(1)For the saturated ammonium sulfate method extraction, the addition of BaCl2 was 4mL/100mL, the saturated (NH4)2SO4 solution concentration percentage was 20%, pH value of 5.5, the temperature was 30℃. Through verification test, the concentration of IgG is 24.22mg/mL.(2)For the low temperature absolute ethyl alcohol precipitation method extraction, the dilution multiple was 3 times, the ethanol recruitment was 25%, the salinity was 0.15mol/L, the pH value was 4.5 as the best craft. Through verification test, the concentration of IgG is 9.283mg/mL.(3)For the caprylic acid-ammonium sulfate method extraction, the saturated (NH4)2SO4 solution concentration percentage was 45%, add bitterness ratio was 1∶25, pH value was 5.5, Through verification test, the concentration of IgG 20.64mg/mL.(4)The three extraction efficiency of saturated ammonium sulfate extraction showed the best and simple, quick, low cost. It was suitable for industrial production. However the low temperature absolute ethyl alcohol precipitation method extraction and the caprylic acid-ammonium sulfate method extraction was cheaper but efficiency was not good enough.(5) The protein solution of IgG was purified by ion exchange method and get an elution peak distribution between 11 to 26. The protein solution what is the light yellow change white liquid and a number of miscellaneous proteins have been filtered. The white liquid was continue to use PBS buffer elution, the other component not found. The DEAE cellulose-52 purified IgG protein solution was concentrated. Polyacrylamide gel electrophoresis was used to for purity and identification of its protein, consistent with the purity of≥95% IgG bands of the standard line and there is no other protein.