Separation of chicken egg white proteins by high-speed countercurrent chromatography

Chicken egg white proteins were fractionated by high-speed counter-current chromatography (HSCCC) using a cross-axis coil planet centrifuge (X-axis CPC). The separation was performed with an aqueous polymer two-phase system composed of 16% polyethylene glycol (PEG) 1000 and 12.5% potassium phosphate buffer at different pH of 6.8, 8.0, and 9.2. From 20 g of the crude egg white solution, the best separation was achieved with a polymer phase system at pH 8.0 by eluting the lower phase at 1.0 mL/min. After the sequential elution of ovotransferrin, ovalbumin, and lysozyme from the column, ovomucin still retained in the column was eluted in the reverse direction with upper PEG-rich phase. All four proteins in the CCC fractions were identified by SDS gel electrophoresis with Coomassie brilliant blue staining.