Optimal amphiphile concentration for lysozyme extraction using reverse micelles

The optimal AOT concentration for the extraction of lysozyme using reverse micelles was investigated, focusing on both the amount recovered and the activity of the enzyme. At a lysozyme feed concentration of 5.0 x 10(-4) M, the total percentage extraction (E) reached a maximum at ca. 80 nm AOT. The lysozyme relative specific activity (RSA) decreased at AOT concentrations higher than 100 mM, and the optimal AOT concentration for maximum recovery of activity (E x RSA) was found to be 80 mM AOT. Recovery of activity was almost 100% at protein concentrations less than 1.0 x 10(-4) M and CD measurements showed that the lysozyme molecular conformation after the extraction was well preserved.