Susceptibility of Escherichia coli and Clostridium perfringens to sucrose monoesters of capric and lauric acid

Abstract

The sucrose monoesters of capric and lauric acid were tested for their antibacterial activity towards two foodborne enteropathogenic bacteria - Escherichia coli (CCM 3954 - serotype O6 and E22 - serotype O103) and Clostridium perfringens (CNCTC 5459 and CIP 105178). Antibacterial activity was evaluated by the plating technique. Sucrose monocaprate significantly decreased the number of viable cells of E. coli at all tested concentrations (0.1-5 mg/ml). The overnight incubation of C. perfringens with the sucrose ester of lauric acid at 0.1-5 mg/ml reduced the number of viable cells below the detection limit (2 log10 CFU/ml). Incubating E. coli CCM 3954 and C. perfringens CNCTC 5459 with monoesters (0.1 and 2 mg/ml) did not influence the K+ permeability of the cytoplasmic membrane in cells during a 2.5-minute treatment. A 30-minute incubation of E. coli CCM 3954 and C. perfringens CNCTC 5459 with esters (0.1 and 2 mg/ml) revealed damage to cytoplasmic structures, as observed by transmission electron microscopy.