INVESTIGADORES
RAPISARDA Viviana Andrea
congresos y reuniones científicas
Título:
Effect of oxidative treatments on bacterial biofilms of potential foodborne pathogens
Autor/es:
OLMEDO, G. M.; GRILLO-PUERTAS, M.; CERIONI, L.; RAPISARDA, V. A.; VOLENTINI, S. I.
Lugar:
Rosario
Reunión:
Congreso; IX Congreso SAMIGE 2013; 2013
Resumen:
In food industry, contamination with pathogen bacteria can occur during growing, harvesting, processing, storing, and shipping
of fresh or minimally processed products. Thus, the study of disinfectants to eliminate undesirable microorganisms is relevant.
Oxidizing biocides such as hypochlorite and peroxides are widely used in sanitization of food and contact surfaces, because of
their antimicrobial effects, availability and low cost. In our laboratory, a sequential oxidative treatment (SOT) has been previously
standardized for the elimination of fungal phytopathogens and Xanthomonas citri subsp. citri, consisting in two sequential
incubations, first with NaClO, and then with H2O2 in presence of Cu2SO4. These compounds generated a synergistic effect.
Here, we tested the capacity of the oxidizing compounds to inhibit and remove bacterial biofilms. Assays were carried out on
polystyrene surfaces, using Escherichia coli C, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium as
pathogenic and surrogate foodborne bacteria. As a preventive treatment for biofilm formation, an optimal combination of NaClO,
H2O2 and Cu2SO4 was established for each strain. E. coli and K. pneumoniae biofilm formation was inhibited by the
application during 2 min of 5 ppm NaClO, 0.1 mM CuSO4 and 100 mM H2O2, whereas S. Typhimurium biofilm was inhibited
applying 5 ppm NaClO, 0.1 mM CuSO4 and 200 mM H2O2. Compounds were also combined to evaluate their disinfectant
action in biofilm remotion. With a time of contact of 5 min, the effective treatments were: 5 ppm NaClO, 0.1 mM CuSO4 and 100
mM H2O2 for E. coli; 12 ppm NaClO, 0.1 mM CuSO4 and 250 mM H2O2 for K. pneumoniae; 10 ppm NaClO, 0.1 mM CuSO4
and 200 mM H2O2 for S. Typhimurium. Oxidative treatment represents a simple technique that involves short times of contact
between the compounds and bacteria. Thus, we propose it as a disinfection strategy to prevent and eradicate bacterial biofilms
from food contact surfaces.