Abstract:The separation and purification of Immunoglobulin of egg yolk (IgY) were studied. The mixture of yolk and water (1:8, v/v) was stirred for 10 min and then its pH value was adjusted to 5.2 with HCl. After placing the mixture for 2 h at 4 ℃, the supernatant was diluted with 95% ice ethanol (-20 ℃) until its concentration reached 60% (v/v). Then the solution was stirred for 20 min at 4 ℃ and centrifuged (22000 r/min) for 25 min at 4 ℃. The precipitate was collected and added into 0.028 mol/L NaCl solution. The corresponding suspension was filtered at 4 ℃ to remove the lipoprotein sediment and the filtrate was then purified by SDS-PAGE methods, giving the protein IgY with the purify of 98%. Its activity was determined with Escherichia coli (E.coli) and results showed that this purification method could well maintain the activity of IgY.
