Selection of the Most Efficient Protocol for the Immunoglobulin Y Extraction from Hen Egg Yolk
Four protocols of immunoglobulin Y extraction and purification from hen egg yolk were compared and the optimal one was chosen from the viewpoint of the purity and yield of the final protein preparation. The following protocols were tested: 1) three-step treatment of the yolk substance with caprylic acid; 2) delipidation with dextran-sulfate followed by sodium sulfate fractionation; 3) removal of lipids via diluting by acidified water followed by sodium sulfate fractionation and 4) purification of immunoglobulins with the use of egg yolk freezing-thawing. Protein yields were assessed as amounts of the total protein in the final immunoglobulin preparations; purity was assessed via polyacrylamide gel electrophoresis in denaturing (reducing and non-reducing) conditions. The protocol of the immunoglobulin Y extraction with the removal of lipids via diluting by acidified water followed by sodium sulfate fractionation was considered as the optimal one, with regard to the ratio between the protein yield and immunoglobulin preparation purity. This protocol can be employed both for the preparation of immunoglobulin Y samples for further affinity purifications of specific antibodies for research purposes and for the production of immunoglobulins Y as pharmaceutics.