Lipase-catalyzed synthesis of 2-ethylhexyl palmitate in a solvent free system using step changes in temperature

Lipase-catalyzed synthesis of 2-ethylhexyl palmitate (2-EHP) from 2-ethylhocyl alcohol and palmitic acid was carried out in a solvent-free system. A commercial liquid lipase (Eversa Transform 2.0, Novozymes) from Thermomyces lanuginosus was immobilized on Lewatit VP OC 1600, a macroporous hydrophobic carrier. The efficacy of this Eversa immobilized lipase prepared in this study was evaluated on the synthesis of 2-EHP compared with that of Novozym 435 (from Candida antarctica), Lipozyme RM IM (from Rhizomucor miehei), Lipozyme TL IM (from Thermomyces lanuginosus), and the liquid Eversa lipase (commercial name: Eversa Transform 2.0). Among these lipases, the Eversa immobilized lipase was the most effective for the synthesis of 2-EHP. Optimum conditions for the synthesis of 2-EHP using this enzyme were a temperature of 55 degrees C and enzyme loading of 2% (based on the total weight of substrate). The conversion of 97% was achieved under these optimum conditions. Finally, as a cost-saving strategy, a step change in the reaction temperature was introduced. When a step change in the reaction temperature between 55 degrees C and 45 degrees C used, an identical degree of conversion was achieved compared to a constant reaction temperature of 55 degrees C throughout the reaction.

Automated summary

In this study, lipase-catalyzed synthesis of 2-ethylhexyl palmitate (2-EHP) was successfully carried out in a solvent-free system. The Eversa immobilized lipase showed the highest efficacy among various lipases tested for the synthesis of 2-EHP. Optimal conditions for the synthesis were found to be a temperature of 55 degrees C and enzyme loading of 2%, resulting in a conversion rate of 97%. Introducing a step change in reaction temperature from 55 degrees C to 45 degrees C did not affect the conversion rate significantly.