Abstract Enzymatic synthesis of ethyl lactate was studied in organic solvents and in ionic liquids to determine optimal media for the reaction, and to investigate the effect of water content on the ester yield. Experiments proved that Cyphos 202 ionic liquid is the best solvent affording the highest ethyl lactate yields. Furthermore, 20 times less enzyme sufficed to carry out the reaction in this ionic liquid compared to organic solvents; ionic liquid could ...