Candida rugosa lipase immobilized on hydrophobic support Accurel MP 1000 in the synthesis of emollient esters

Abstract

Objectives: To immobilize Candida rugosa lipase in Accurel MP 1000 (CRL-AMP) by physical adsorption in organic medium and apply in the synthesis of wax esters dodecanoyl octadecanoate 1 and hexadecanoyl octadecanoate 2 in a heptane medium, as well as evaluating the stability and recyclability of CRL-AMP in six reaction cycles.

Results: The specific activity (A_sp) 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 six consecutive cycles of reaction showed that the biocatalyst retained approximately 50% of its original activity for both reaction systems.

Conclusions: 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.

Keywords: Accurel MP 1000; Biocatalysis; Esterification; Immobilization.