Lipid‐lipase interactions. 2. A new method for the assay of lipase activity

A simplified procedure for the measurement of activity was developed for lipases (EC 3.1.1.3) fromChromobacterium viscosum, Candida rugosa, Aspergillus niger andRhizopus arrhizus. It differs from existing procedures in that olive oil, refined with a bleaching clay, was used as the substrate, periodic sonication was applied to promote efficient emulsification, the hydrolysis time was extended to 1 hr, and no additive such as protective colloids and surfactants were used. The activity was determined arbitrarily for that amount of lipase required to bring about 24% hydrolysis/hr at room temperature Unlike currently used assay procedures, the present method gives results which are highly reproducible with a maximum standard deviation of 2.5% and, more commonly, less than 1.00%.