24] Stabilization of lipases against deactivation by acetaldehyde formed in acyl transfer reactions

Abstract

Publisher Summary Acetaldehyde, which emerges as an unavoidable by-product in lipasecatalyzed acyl transfer reactions from vinyl esters can cause severe deactivation of enzyme activity and selectivity. The extent of the deactivation is dependent on the enzyme's structure, which, in turn, is governed by its microbial source. Whereas the majority of industrially produced lipases are remarkably stable toward acetaldehyde, the C. rugosa and G. candidum enzyme is highly sensitive. Two methods for the stabilization of C. rugosa lipase have been employed. (1) Covalent immobilization onto an epoxy-activated carrier resin is suitable for small-scale reactions. This technique stabilizes the enzyme activity and increases its enantioselectivity about fivefold compared to the native enzyme. (2) Adsorption onto Celite 545 may serve as a more economic alternative for large-scale applications. The stabilizing effect on activity and enantioselectivity is only slightly less pronounced compared to the covalent immobilization.