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We evaluated the influence of temperature on the ability of Salmonella Enteritidis (SE) to form biofilms on stainless steel, polyethylene, and polyurethane surfaces under different hygiene procedures. These materials were placed on SE culture and incubated at 42±1 ºC, 36±1 ºC, 25±1 ºC, 9±1 ºC, and 3±1 ºC for 4, 8, 12, and 24 h. Hot water at 45 ºC and 85 ºC, 0.5% peracetic acid solution, and 1% quaternary ammonia were used for hygienization. Biofilm formation occurred at all temperatures evaluated, highlighting at 3 ºC which has not been reported as an ideal temperature for the adhesion of SE to these materials. The SE adhered more often to polyethylene surfaces than to polyurethane and stainless steel surfaces (P<0.05). Peracetic acid and water at 85 ºC had similar hygienization efficiency (P<0.05) followed by quaternary ammonia whereas water at 45 ºC was not effective. SE adhered to these materials under low temperatures which to date have been deemed safe for food preservation.

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Aims: To perform the isolation, characterization and sequencing of the bacteriophages. To demonstrate that the bacteriophages can be used for biocontrol of different Salmonella enterica serovars. Study Design: This study was an experimental study. Place and Duration of Study: Bacteriology and Mycology Laboratory in the Veterinary Hospital at the Faculty of Agronomy and Veterinary Medicine of the University of Passo Fundo (FAMV/UPF), Biotechnology Center (CBiotec) of the Federal University of Paraíba (UFPB), Center for Microscopy and Microanalysis at the Faculty of Veterinary of the Federal University of Rio Grande do Sul (UFRGS), between January – September 2016. Methodology: Twelve Salmonella enterica serovars (S. Anatum, S. Agona, S. Brandenburg, S. Bredeney, S. Infantis, S. Lexington, S. Panama, S. Rissen, S. Schwarzengrund, S. Tennessee, S. Enteritidis ATCC 13076 and S. Typhimurium ATCC 14028) were selected to be the hosts. We isolate, purify, produce and determine the bacteriophage titers to verify the potential for lysis of these phages against the hosts. Having determined the action of the phages against the hosts, we performed the sequencing of the bacteriophages on the Illumina Mi-Seq platform and the morphology was performed by transmission electron microscopy (TEM). Results: We isolated, characterized and sequenced the genome of two new bacteriophages, Salmonella phage UPF_BP1, belonging to the family Podoviridae and Salmonella phage UPF_BP2, family Myoviridae. UPF_BP1 has lytic action against seven tested Salmonella enterica serovars, while UPF_BP2 has action against the twelve tested serovars. Conclusion: The two new bacteriophages have a lytic action against different Salmonella enterica serovars, feeding our expectations for the development of alternatives for the use of antimicrobials, being possible candidates for use as a biocontrol of Salmonella enterica in food, animals and the environment.

Salmonella remains one of the most common foodborne pathogens worldwide, and its resistance to antimicrobials has increased considerably over the years. In this context, was evaluated the action of three bacteriophages isolated or combined in inhibiting the adhesion and removal of Salmonella Heidelberg biofilm on a polystyrene surface. The bacteriophages UPF_BP1, UPF_BP2, UPF_BP3 and a pool of them were used for biocontrol of Salmonella Heidelberg biofilms on polystyrene surface in the action times of 3, 6 and 9 h. Individual and combined phages exhibited reductions in Salmonella Heidelberg adhesion of up to 83.4% and up to 64.0% in removal of preformed biofilm. The use of synergistic combinations between the phages is the most indicated option due to its potential to reduce biofilms. The use of the bacteriophage pool in surface conditioning is an alternative in the control of Salmonella Heidelberg biofilms.

Salmonella Enteritidis é capaz de formar biofilmes no ambiente de processamento de alimentos podendo levar a surtos de doenças transmitidas por alimentos. Neste trabalho, avaliou-se a capacidade da S. Enteritidis formar biofilme em corpos de prova de aço inoxidável, polietileno e poliuretano a 3±1ºC, 9±1ºC, 25±1ºC, 36±1ºC e 42±1ºC, após 0, 4, 8, 12 e 24 horas de incubação. Foram realizados testes com o uso de água a 45°C e a 85°C, e com soluções de ácido peracético e amônia quaternária para remoção dos biofilmes. Ambas as cepas aderiram no aço inoxidável, no polietileno e no poliuretano, e em todas as temperaturas de exposição, inclusive a 3ºC e 9ºC. O ácido peracético revelou-se o melhor tratamento na remoção dos biofilmes. De maneira geral, os resultados demonstraram que esses materiais, utilizados na indústria de alimentos, propiciaram a aderência das S. Enteritidis nas diferentes condições ambientais. Os resultados são importantes para o desenvolvimento de estratégias de controle de biofilmes na indústria, já que a presença desse microrganismo aderido pode comprometer a qualidade do alimento processado e consequentemente ter impacto na saúde pública.