Bactericidal synergism through enterocin AS-48 and chemical preservatives against Staphylococcus aureus.
OBJECTIVE
To determine the effectiveness of enterocin AS-48 on Staphylococcus aureus CECT 976 in combination with chemical preservatives at acidic and neutral pH.


RESULTS
At pH 4.5, the activity of AS-48 increases in the presence of lactic acid (1.0%), acetic acid (0.5% and 1.0%), and citric acid (0.3% and 0.6%). This synergistic effect has also been observed during the first 8 h of incubation with benzoate (0.06% and 0.12%) and sorbate (2% and 3%). Interestingly, at pH 7, lactate (1%) increases the inhibitory effect of AS-48, reducing the S. aureus population by 6 log units compared with the control culture. At neutral pH, combinations of AS-48 and sodium tripolyphosphate, STPP (0.3% and 0.5%) also eliminate this pathogen after 24 h.


CONCLUSIONS
These results indicate that enterocin AS-48 could be applied in combination with a range of chemical preservatives in order to increase its efficacy in inhibiting S. aureus.


CONCLUSIONS
This study supports the potential use of enterocin AS-48 as a biopreservative to control S. aureus in combination with other food-grade chemical hurdles.
Ananou
S
S
Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Granada, Spain.
Maqueda
M
M
Martínez-Bueno
M
M
Gálvez
A
A
Valdivia
E
E
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001430:Bacteriocins / Q000494:pharmacology*; D001565:Benzoates / Q000494:pharmacology; D002264:Carboxylic Acids / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004357:Drug Synergism; D004768:Enterotoxins / Q000378:metabolism; D005520:Food Preservatives / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D011122:Polyphosphates / Q000494:pharmacology*; D013011:Sorbic Acid / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D001565:Benzoates; D002264:Carboxylic Acids; D004768:Enterotoxins; D005520:Food Preservatives; D011122:Polyphosphates; C466236:enterocin AS-48, Enterococcus faecalis; C026066:enterotoxin A, Staphylococcal; C005692:triphosphoric acid; D013011:Sorbic Acid