Synergistic effect of enterocin AS-48 in combination with outer membrane permeabilizing treatments against Escherichia coli O157:H7.
OBJECTIVE
To determine the effects of outer membrane (OM) permeabilizing agents on the antimicrobial activity of enterocin AS-48 against Escherichia coli O157:H7 CECT 4783 strain in buffer and apple juice.


RESULTS
We determined the influence of pH, EDTA, sodium tripolyphosphate (STPP) and heat on E. coli O157:H7 CECT 4783 sensitivity to enterocin AS-48 in buffer and in apple juice. Enterocin AS-48 was not active against intact cells of E. coli O157:H7 CECT 4783 at neutral pH. However, cells sublethally injured by OM permeabilizing agents (EDTA, STPP, pH 5, pH 8.6 and heat) became sensitive to AS-48, decreasing the amount of bacteriocin required for inhibition of E. coli O157:H7 CECT 4783.


CONCLUSIONS
The results presented indicate that enterocin AS-48 could potentially be applied with a considerably wider range of protective agents, such as OM permeabilizing agents, with increased efficacy in inhibiting E. coli O157:H7.


CONCLUSIONS
Results from this study support the potential use of enterocin AS-48 to control E. coli O157:H7 in combination with other hurdles.
Ananou
S
S
Departamento de Microbiología, Universidad de Granada, Granada, Spain.
Gálvez
A
A
Martínez-Bueno
M
M
Maqueda
M
M
Valdivia
E
E
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001628:Beverages; D001952:Bridged-Ring Compounds / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects; D002614:Chelating Agents / Q000494:pharmacology; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000187:drug effects*; D005506:Food Contamination; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D027845:Malus
D000900:Anti-Bacterial Agents; D001952:Bridged-Ring Compounds; D002614:Chelating Agents; C012306:enterocin