Enzymatic Synthesis of l-Ascorbyl Laurate in DMSO–Acetone Mixed Solvent

In the present study, a dimethyl sulfoxide (DMSO)–acetone mixed solvent was used as a reaction medium to study lipase-catalyzed esterification of l-ascorbic acid with lauric acid as the acyl donor. Compared with the solvent of acetone, the mixed solvent not only could greatly improve the solubility of l-ascorbic acid but also could observably increase the enzymatic rate. Within the investigated range of substrate concentrations, a lauric acid/ascorbic acid mole ratio of 3:1 was found to be optimum. Moreover, the optimum production was achieved in the reaction medium dewatered by molecular sieves and at a lipase loading of 40 mg/mL. As a result, enzymatic synthesis of ascorbyl laurate gave a maximum conversion of 94% in the DMSO–acetone mixed solvent using lauric acid as the acyl donor.