Glycerol carbonate was synthesized as biosolvent for the development of soluble enzymatic system. The effects of various reaction parameters on activity and stability of lipases were investigated using the transesterification of ethyl butyrate with n-butanol as a model reaction. Enzymatic activity in glycerol carbonate was compared with that in water and in conventional organic solvents with different ionizing and dissociating abilities. The pK(a) value of trichloroacetic acid and transesterification activities of Candida antarctica lipase B and Candida rugosa lipase in glycerol carbonate are similar to those in water, indicating that ionizing and dissociating powers are capable of satisfactorily predicting the biocompatibility of organic solvents for soluble enzymatic systems. (C) 2011 Elsevier Inc. All rights reserved.