Silica‐Mediated Incorporation of Lipase Into the Bulk of a Deep Eutectic Solvent: An Efficient Biocatalytic Phase for Esters Synthesis

Abstract Aiming at sustainable solutions suitable for industrial‐scale catalysis catalytic phase containing lipase and deep eutectic solvent (DES) was designed. To achieve this, both physical and chemical immobilizations of lipases were performed on the surface of silica and carbon materials. The catalytic activity of developed biosystem was tested in biotransformation of α‐angelica lactone into butyl levulinate at 60 °C. The best results were achieved for Candida antarctica lipase B adsorbed on fumed silica suspended in choline chloride: glycerol (1:2) with the addition of 20 wt% of water. Under these conditions 99.9% conversion of α‐angelica lactone and 100% selectivity to butyl levulinate were obtained after 45 min. The biocatalytic system maintained its activity for up to five consecutive reaction cycles with full conversion of lactone to ester. The heterogenization of the enzyme allowed the biocatalyst to be integrated into the bulk of the DES, which includes essential water. This combination resulted in the formation of a stable and easy‐to‐operate catalytic phase where reagents formed a second organic phase. The integration of cost‐effective biocatalyst with process efficiency provides a greener alternative with significant potential for industrial use.