Comparison of lipases by different assays

Lipases are enzymes of interest in different disciplines in natural science: medicine, biochemistry, biology, the food industry, and in recent years, organic chemistry. Although the type of enzyme is the same with respect to different aims, lipases are defined as enzymes that hydrolyze emulsified triacylglycerols. The aim of this investigation is to point out that for biotechnological applications, a broader definition of lipases is necessary. A set of different assays based on hydrolytic and synthetic activities were used to characterize lipases enabled results to be compared for lipases as catalysts in organic synthesis and in homogenous phases. Sixty lipases were screened with different assays to determine the optimal method for the detection of each lipase and the aim to replace the classical, more complicated assay (pH-stat). Some lipases proved to be significantly more active with certain artificial substrates at concentrations where no evaluable activity was found with the pH-stat method.