Specific Inhibition of Esterase in Ester-Hydrolysing Enzyme Systems

Abstract

IN trying out several emulsifying agents having at a fairly neutral pH a stabilizing effect upon emulsions of olive oil, monobutyrine, ethylbutyrate, methylbutyrate and ethylpropionate, the following observations were made. Gummi arabicum activates on one hand the cleavage of olive oil to a very remarkable degree, but exerts no influence upon the cleavage of monobutyrine. It causes on the other hand a very sharp inhibition of the saponification of such esters where glycerol is substituted by lower alcohols. This inhibitory effect amounted in several instances (depending upon the source of the lypolytic enzymes employed) to 100 per cent, and in no case was finally less than 65 per cent. In the tests with olive oil, the activating effect of gummi arabicum proved to be dependent upon the stability of the emulsion, which on its part depends principally upon the procedure of preparation and to a much less degree upon the absolute amount of gummi arabicum added. Thus, in several instances, where no stable emulsions were obtained, the activating effect was either nil or very small.