Inibição de biofilme de Salmonella Minnesota por agentes sanitizantes

Abstract

Salmonellosis is an important food-borne gastroenteritis that strikes humans. The gastrointestinal tract of chickens is one of the main reservoirs of this etiological agent, and

thus the meat of these animals can be contaminated during the stages of slaughter. The ability to form biofilms is an important way of maintaining this microorganism in the environment, both on the farm and in the industry, which increases the chances of bird infection and meat contamination. Thus, prevention and control of the Salmonella sessile form of life is extremely important to ensure the microbiological quality of the meat produced and the safety of the consumer. The objective of this study was to evaluate the formation of biofilms on the surfaces of stainless steel, polyurethane and polypropylene by S. Minnesota and the effectiveness of contact for 15 minutes of the sanitizers sodium hypochlorite 1% and peracetic acid 0.8% in its inhibition. Three different strains of S. Minnesota previously isolated for the formation of biofilms on the surfaces of the three materials (slides) were used. The biofilms were evaluated by the classical method of violet crystal staining and optical density reading (DO600) and used a formula for the classification of the strains as strong, weak or without biofilm formation capacity. The formed biofilms were submitted for 15 minutes to sanitizers 1% sodium hypochlorite and 0.8% peracetic acid. The viable cell count of S. Minnesota was performed on biofilms before and after treatment with the sanitizers. The ability of S. Minnesota to form biofilms classified as strong, moderate or weak biomass varied according to strain and surface, with the formation of strong biofilms by all strains when the surface was stainless steel. However, there was no difference in the counts of microorganisms in the formed biofilms, indicating that in the control of these communities it is preferable to use chemical agents with action also in the extracellular matrix. The use of sodium hypochlorite 1% showed an action superior to the use of peracetic acid 0.8% in the inhibition of the communities, regardless of the strain and the surface in which it was formed.