Sugar fatty acid ester surfactants: Base-catalyzed hydrolysis

Rate constants for the base-catalyzed hydrolysis of sucrose laurate, sucrose alpha-sulfonyl laurate, and sucrose alpha-ethyl laurate were measured at several temperatures in pH 11 buffer. Activation energies and Arrhenius factors for the hydrolysis reactions were determined. Ar 27 degrees C, sucrose laurate hydrolyzed fastest and sucrose alpha-ethyl laurate slowest. Activation energies and Arrhenius factors showed that both steric and electronic factors affect the rates of ester hydrolysis. Other work has shown that bacterial hydrolysis of sugar fatty acid esters is inhibited in the presence of either alpha-sulfonyl or alpha-alkyl groups. A kinetic study of base-catalyzed ester hydrolysis has revealed reasons for the inhibition of bacterial hydrolysis and provided information regarding ester stability at elevated pH.