INVESTIGADORES
QUIBERONI Andrea Del Lujan
artículos
Título:
Hard Surfaces Decontamination of Enteropathogenic and Shiga Toxin-Producing Escherichia coli using Bacteriophages
Autor/es:
TOMAT, D.; QUIBERONI, A.; MERCANTI, D.; BALAGUÉ, C.
Revista:
FOOD RESEARCH INTERNATIONAL
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2014 p. 123 - 129
ISSN:
0963-9969
Resumen:
Three Myoviridae phages (DT1, DT5 and DT6) specific for pathogenic Escherichia coli were studied, either individually or as cocktails, for their lytic activity on in vitro challenge tests. Also, cocktails ability to reduce artificial contamination on hard surfaces (glass coverslips and stainless steel coupons) by three pathogenic Escherichia coli strains (EPEC920, non-O157 STEC ARG4827 and O157:H7 STEC464) was tested. Assays of phage stability during refrigerated storage showed that the three phages evaluated retained a high viability after two months at 4°C. Challenge tests showed high reductions in viable cells, of up to 6.438 log CFU/ml, for all tested strains at 37ºC. Efficiency was somewhat lower at 4°C, though biocontrol levels were still good, reaching values of up to 3.879 log CFU/ml. Considering only results obtained at 37°C, phage cocktails produced the highest reduction in most cases. Treatments with phage cocktails produced complete inactivation (ca. 5-6 log CFU/ml) of EPEC920 and O157:H7 STEC464 on glass coverslips, and of EPEC920, non-O157 STEC ARG4827 and O157:H7 STEC464 on stainless steel coupons, at both temperatures (4ºC and 37°C) and multiplicity of infection (ca. 10exp3 and 10exp7) tested. However, some strains not detected at 3 h were sometimes detected at 24 h, and inactivation of non-O157 STEC ARG4827 on glass coverslips was never accomplished; viable cells reductions in all these cases ranged from 1.25 to 5.437 log CFU/ml. Our results suggest that lytic phages, either individually or as a cocktail, may be useful for reducing contamination on hard materials used in food processing surfaces. To our knowledge, this is the first study focused on the use of bacteriophages to reduce contamination of food processing surfaces by EPEC and non-O157 STEC strains.
