Activity and stability of lipase in Aerosol-OT/isooctane reverse micelles

The stability of Candida rugosa lipase, which catalyzes the hydrolysis reaction of olive oil in AOT/isooctane reverse micelles, decreased with the increase of ₀ (defined as the molar ratio of water to surfactant) and Aerosol-OT concentration. The addition of a non-ionic cosurfactant, tetraethylene glycol dodecyl ether (C₁₂E₄), preserved enzymatic activity. The residual activity of the lipase was 53% after 24 h, while the enzyme completely lost its activity within 6 h in the absence of C₁₂E₄ addition. The stabilizing effect of C₁₂E₄ resulted in the increase of conversion. The enhancement of the activity and stability of lipase in reverse micelles by the addition of C₁₂E₄ may contribute to increase the rigidity of the micellar matrix stabilizing the enzyme structure.