The properties of four commercial lipases from Chromobacterium viscosum, CvL 1-4, in ester synthesis were investigated. Three lipases showed a high synthetic activity in esterification, with conversions of oleic acid as high as 86-95% in 24 h, whereas one (CvL 1) gave a poor result of only 11% with the same quantity of 9 mg crude lipase preparation. The elution profiles of the four lipasesfrom Sephacryl S-100 HR differed and SDS-PAGE suggested that while CVL 1 lipase had two equivalent protein bands of molecular size 33 and 27 kDa, respectively, the other three lipases showed only one main protein band of 33 kDa. Isoelectric focusing revealed that all of the lipases contained several isoforms, but the proportions of the isoforms varied. Furthermore, both aggregated and single lipase forms obtained after gel filtration were able to catalyse ester synthesis, but the two lipases from CvL I showed lower synthetic activities than the others.