Purification of egg yolk phosvitin by anion exchange chromatography

The objective of this study was to develop a simple method of phosvitin purification from hen egg yolk without using organic solvents. Egg yolk was diluted with equal volume of water and stirred for one hour at room temperature, followed by centrifugation to remove soluble proteins along with most of the yolk lipids in the supernatant. The granules were collected as the precipitate containing minimum amount of lipids (dry granules). The dry granules were dissolved in 0.05 M carbonate–bicarbonate buffer at pH 9.6, which yields a light yellowish solution used for anion exchange chromatography. Phosvitin fraction was collected from anion exchange chromatography as the last eluting peak with a purity of 92.6% and a yield of 35.4% of total phosvitin in the yolk or a recovery of 1.9% of total yolk dry matter, which are comparable to current methods employing organic solvents or chromatography after salt fractionation and dialysis. This method developed is simple and fast without using organic solvents.

► Phosvitin is a highly phosphorylated protein representing ∼4% of yolk dry matter. ► A simple method for purifying phosvitin from egg yolk was developed. ► The method did not involve any organic solvent. ► Phosvitin was purified by anion exchange chromatography. ► Phosvitin prepared has a purity of 92.6% and a yield of 35.4%.