The determination of antimicrobial and antibiofilm activities of foodborne lactic acid bacteria against Enterobacter cloacae isolates

Abstract

The aim of this study was to investigate the antimicrobial and antibiofilm activities of 10 different lactic acid bacteria (LAB)strains isolated from local food sources of animal origin against 4 Enterobacter cloacae isolates obtained from clinical cases and determinetheir adhesion potentials to intestinal epithelial cells. In this study, all Enterobacter cloacae isolates (P3, P4, P5, P7) identified with theBD Phoenix automation system were detected to form biofilm with both Congo red agar and Microtiter plate methods. Amoxicillinclavulanate,cefuroxime, and ampicillin resistance was determined in all isolates. It was determined that LAB strains producingexopolysaccharide (EPS) were able to colonize intestinal epithelial cells. It is noteworthy that LAB extracts were effective to inhibitthe biofilm formation of P3Ec, which had higher antibiotic resistance than those of other isolates. Antimicrobial effect of LAB extractson Enterobacter cloacae were also detected by both agar disc diffusion and well diffusion tests. In this study, all of the isolated LABstrains (especially L. lactis, L. fermentum, and L. casei) are good candidates for controlling Enterobacter cloacae biofilm formation. Thesefindings indicate that L. lactis, L. fermentum, and L. casei can potentially be developed as novel antibiofilm agents.