Candida Rugosa Lipase Immobilized on Hydrophobic Support Accurel MP 1000 in the Synthesis of Emollient Esters

Abstract

In the present work, Candida rugosa lipase (CRL) was immobilized by physical adsorption in organic medium on Accurel MP 1000 (AMP) with a protein load of 6.5 mg g-1 (mg protein/g support). CRL-AMP was applied with 5 and 10% of catalyst/volume of medium (m v-1) in esterification reactions of stearic acid with lauryl and cetyl alcohols producing the wax esters such as dodecanoyl octadecanoate 1 and hexadecanoyl octadecanoate 2 in a heptane medium. Six reaction cycles were studied to evaluate the stability and recyclability of the prepared biocatalyst. The specific activity (Asp) for CRL-AMP was 200 ± 20 U mg-1. Its catalytic activity was 1300 ± 100 U g-1. CRL-AMP was used in the synthesis of esters in heptane medium with a 1:1 acid:alcohol molar ratio at 45°C and 200 rpm. In synthesis 1, conversion was 62.5 ± 3.9% in 30 min at 10% m v-1 and 56.9 ± 2.8% in 54 min at 5% m v-1, while in synthesis 2, conversion was 79.0 ± 3.9% in 24 min at 10% m v-1, and 46.0 ± 2.4% in 54 min at 5% m v-1. Reuse tests after 6 consecutive cycles of reaction showed that the biocatalyst retained approximately 50% of its original activity for both reaction systems. CRL-AMP showed a high potential in the production of wax esters, since it started from low enzymatic load and high specific activities and conversions were obtained, in addition to allowing an increase in stability and recyclability of the prepared biocatalyst.