Reversed Micellar Extraction of Hen Egg Lysozyme

Egg white was diluted to 10 times its original volume with 50 mM phosphate buffer (pH 9.2) containing 0.1 M potassium chloride. The aqueous solution was mixed with an equal volume of isooctane containing 50 mM bis-(2-ethylhexyl) sodium sulfosuccinate at 10°C for 50 min. After extraction, the organic phase containing lysozyme was separated from the aqueous phase and mixed with an equal volume of 50 mM phosphate buffer (pH 11.8) containing 1M potassium chloride. Backward extraction was then performed at 30°C for 45 min. The procedures recovered 90% lysozyme from the eggwhite. The specific activity of the extract was near 73,000 units/mg.