Selective Precipitation of Lysozyme from Egg White Using AOT

Lysozyme from egg white was purified using the anionic surfactant, di‐(2‐ethylhexyl) sodium sulfosuccinate (Aerosol‐OT or AOT), as a precipitating ligand. Upon addition, AOT formed an insoluble lysozyme‐surfactant complex with lysozyme and precipitated from the egg white solution. The lysozyme was then recovered as a solid from the insoluble complex using acetone, while AOT remained in the acetone phase. The precipitation efficiency was highest when the pH of the egg white solution was between 6 and 9. A molar ratio of 15 between surfactant and lysozyme provided 80% precipitation efficiency. The recovered lysozyme product was free of surfactant, and retained its original enzymatic activity.