Investigation of Two Precipitation Methods for Extracting Immunoglobulin Y (IgY) from Egg Yolks

Two groups of hens (control and immunization group) were arranged in an experimental design with an immunization schedule of 3 injections of BSA antigen. IgY antibodies were extracted from egg yolks by two precipitation processes (chloroform and polyethylene glycol precipitates) and quantified using a standard curve of protein concentration. The purification of IgYwas confirmed by SDS-PAGE. Total protein extracted from egg yoks were less contaminated with yellow pigments (lutein and zeaxanthin) by using chloroform precipitate. The 2nd week post-immunization, IgY concentration increased respectively to 3903 ± 726 μg.ml-1 (chloroform extraction process) and 2937 ± 294 μg.ml-1 (PEG extraction process) (P < 0.01). After 3rdimmunization, IgY level obtaining from in immunization group extracted by chloroform process (6633 ± 1166 μg.ml-1) increased 2.7 times higher than that in control group (2482 ± 414 μg.ml-1). Whereas IgY concentrations obtained from PEG extraction process were not significantly different between the experimental group and control group. Chloroform and PEG precipitation methods had the same protein profile on the SDSPAGE. IgY antibody was identified by the presence of bands corresponding with IgY heavy chain (67-70 kDa) and IgY light chain (25 kDa) for both precipitation processes.