Studies On Fractionation And Extraction Of Immunoglobuling From Porcine Blood

Immunoglobulin (Ig) secreted by B lymphocyte that function was binding the specific antigens in the immune response. The importance of IgG in infant feeding is well-documented in clinical test results: IgG from different resources showed considerable bacteriostatic effect against human enteropathogenic strains of Escherichia coli, Rotavirus and multiple sclerosis infections also could be prevented by oral administration of IgG. Porcine blood is rich in Immunoglobulin and the most important porcine serum Immunoglobulin is IgG.Porcine blood resources are abundant in China, but the utilization weren't enough. So the exploitation and utilization of porcine serum IgG were studied.IgG concentration and other porcine serum protein composition were analyzed by improved Polyacryamide Gel Electrophoresis (PAGE). The content of active IgG was measured by direct Enzyme-Linked Immunoserbent Assay (ELISA). According to the dates of IgG purity, recovery rate and activity preservation, optimal fractionation processing and technological parameters were DeterminedIt was researched that porcine serum IgG fractionation method in laboratory. Ammonia sulfate was used for primary extraction: 80.5%(w/w) porcine serum IgG was precipitated in 37% saturated Ammonia sulfate at pH 7.4 and room temperature, the purity of IgG is 72.9%(w/w). Using Diethylaminoethyl cellulose 52 for advanced purify: 97%(w/w) purity IgG (activity preservation rate is 94%(w/w)) were obtained.IgG of porcine serum was purified when Polyphosphate or Ferric chloride was added. The optimal parameters of Polyphosphate were determined to be as follows: the Polyphosphate concentration is 0.1% (w/v), pH is 3.9, and temperature is 45℃. The recovery rate and purity of extracted IgG are 52.7%(w/w) and 59.1%(w/w) under optimal condition. In porcine serum treated with 4.5mmol/L Ferric chloride at pH 4.5 and 40℃, 75.5%(w/w) Immunoglobulin G (90.5%(w/w) immunochemical activity IgG) and a littleγ-globulin were retained in the supernatant, the purity of IgG is 71.7%(w/w). More than 95%(w/w) added iron was subsequently eliminated as precipitate by holding the treated serum at pH 9. Compared with the methods of Polyphosphate and Ferric chloride, the fractionation processing of Ferric chloride have many merits, such as easy processing, bland process conditions, fractionation effect very well, the products safely and the technics are practicality. So the Ferric chloride fractionation technics is applicable to food industry.The IgG solution fractionated by Ferric chloride was concentrated by spire roll Ultrafiltration membrane module. Ultrafiltration mode is all retention circulates crosscurrent flow. Ultrafiltration membrane is polyethersulfone membrane and retention molecular weight is 10,000Da. The optimal technological parameters of Ultrafiltration concentration were...