Abstract
To determine if solid wax esters are hydrolyzed by enzymes (lipase or esterase) they were dissolved in organic solvents followed by incubation with aqueous solutions of commercial enzymes at 45°C, 500 rpm.
Among the commercial preparations of several microbial enzymes tested, lipases from Candida cylindracea and Rhizopus chinensis were found to act on vegetable wax esters such as rice bran wax, candelilla wax and esparto wax. The carnauba wax ester hardly underwent any hydrolysis by any lipase. There was virtually no reaction of the lipases with the above wax esters in aqueous reaction systems. The time courses of hydrolysis of the wax esters was noted to vary according to the particular lipase used. The amount of each lipase required to bring about the same extent of hydrolysis on the same wax ester differed significantly. These findings may be accounted for primarily on the basis of the substrate specificity of each lipase for the carbon chain length of alcohols and fatty acids which are constituents of the vegetable wax esters. The data of the present study demonstrate the enzymatical hydrolysis of solid wax esters. This is at variance with the generally held notion that solid waxes are not attacked by enzymes.
