Potato peels (PP) contain several bioactive compounds. These compounds are known to provide human health benefits, including antioxidant and antimicrobial properties. In addition, these compounds could have effects on human enteric viruses that have not yet been reported. The objective of the present study was to evaluate the phenolic composition, antioxidant properties in the acidified ethanol extract (AEE) and water extract of PP, and the antiviral effects on the inhibition of Av-05 and MS2 bacteriophages, which were used as human enteric viral surrogates. The AEE showed the highest phenolic content and antioxidant activity. Chlorogenic and caffeic acids were the major phenolic acids. In vitro analysis indicated that PP had a strong antioxidant activity. A 3 h incubation with AEE at a concentration of 5 mg/ml was needed to reduce the PFU/ml (plaque-forming unit per unit volume) of Av-05 and MS2 by 2.8 and 3.9 log₁₀, respectively, in a dose-dependent manner. Our data suggest that PP has potential to be a source of natural antioxidants against enteric viruses.

Four phages isolated from cattle and poultry feces were analyzed for their ability to lyse Salmonella serotypes and Escherichia coli O157:H7. The phage one-step growth curves, morphology, and genetic characteristics were determined. All phages showed a lytic effect on various Salmonella serotypes and E. coli O157:H7, which lysed at least 70% of the 234 strains tested. The phages had latent periods ranging from 10 to 15 min and generation times of 30 to 45 min, while burst size fluctuated between 154 and 426 PFU/cell. Phages morphology showed isometric and elongated heads and rigid contractile tails, consistent with morphology of the Myoviridae family. Phages' DNA dendrograms showed a distinctive RFLP when digested by HindIII and EcoRV, and SDS-PAGE profile showed distinctive proteins expression as well. In vitro phage challenge showed a total reduction of E. coli O157:H7, Salmonella Typhimurium and Saintpaul counts at 2 h, whereas for Salmonella Montevideo a reduction and retardation growth, at a multiplicity of infection (MOI) of 100, was observed; however, under a MOI of 10 000, no viable cells were detected after 4 h. The wide host ranges of these phages suggested they could be used for simultaneous biocontrol of some Salmonella serotypes and E. coli O157:H7.

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The aim of this research was to evaluate the efficacy of bacteriophage Av-08 for reducing Salmonella Montevideo and Escherichia coli O157:H7 presence from chicken skin surface at 4C. Significant reduction (P < 0.05) of S. Montevideo (5.16 log10 colony-forming units [cfu]/4 cm 2 chicken skin) and E. coli O157:H7 (4.9 log10 cfu/4 cm 2 chicken skin) was achieved. When phage was applied to the bacterial mixture, a reduction of 4.4 and 4.69 log10 cfu/4 cm 2 of S. Montevideo and E. coli O157:H7 was obtained on the chicken skin surface, respectively. No significant reduction was observed by buffer application, compared with the control. Phage Av-08 was able to survive on the chicken skin surface at concentrations fluctuating from 7.27 to 8.44 log10 PFU/4 cm 2 for 6 days. These results demonstrated the ability of phage Av-08 in reducing the presence of S. Montevideo and E. coli O157:H7 from chicken skin surface at 4C.