The use of biotransformation in the synthesis of pharmaceutical intermediates, drug metabolites and drug products is now common. Thousands of different strains and enzymes are required to exploit the selective biotransformation potential for the conversion of a myriad of different substrates into the desired products. There is a growing demand for the synthesis of hexyl laurate, an important emollient used in many cosmetic industrial applications. The present work focuses on the synthesis of hexyl laurate by esterification of hexyl alcohol and lauric acid using immobilised lipase. A suitable support called Mesocellular foam (MCF) with a pore size of 19 nm was synthesised and lipase was immobilised on to the support in scCO2 reactor. Candida antractica (CALB) immobilised on MCF was found to be an effective biocatalyst for the synthesis. The effects of various parameters such as speed of agitation, temperature, catalyst loading were systematically studied in detail. The initial rate studies showed that the Michaelis Menten constant for hexyl alcohol was very low indicating high affinity between the enzyme and the reactant. The kinetics was found to obey the ternary complex model with hexyl alcohol substrate inhibition above a particular concentration.
Keywords: Hexyl laurate, Mesocellular foam, Michaelis Menten constant, Esterification
