Potencial toxigênico, deteriorante e susceptibilidade antimicrobiana de espécies de Staphylococcus coagulase positiva isoladas em queijos tipo Minas frescal comercializados no Norte do Estado do Tocantins

Abstract

Foodborne diseases (DTA's) directly affect public health. They may have a bacterial etiology, in which the pathogen Staphylococcus aureus is one of the main etiological agents related to outbreaks of DTA in Brazil. Clandestine products, in this context, present a greater risk to public health because they have not been subjected to any type of sanitary inspection from the raw material to its commercialization, and may contain pathogens potentially capable of causing diseases to consumers. Considering the lack of knowledge about the microbiological hazards of the main foods that cause foodborne diseases in the northern region of Tocantins; on the impact of ATDs on public health; in the collection of technical information on the effectiveness of antimicrobial active principles against food pathogens; and in the lack of theoretical-scientific basis for the elaboration of specific prophylactic programs of control and epidemiological and sanitary surveillance of the risk of occurrence of dangers of foods of animal origin informally commercialized in the north of the state of Tocantins, the present work had as objective to identify in cheeses clandestine fresh mines, coagulase-positive staphylococci species (ECP) through biochemical tests such as the ability to hemolysis, acetoin production and sugar fermentation; to evaluate its enterotoxigenic potential, by molecular approach; and the deteriorating potential under different temperature conditions; as well as its antimicrobial susceptibility through the disk diffusion technique. Twenty-one samples of cheese commercialized informally in the north of the state of Tocantins were evaluated. Of the total of 355 ECP isolates, 177 (49.86%) were identified as S. aureus, 2 (0.56%) S. intermedius, 3 (0.84%) S. hycus, 2 (0.56%) S. delphini, and 1 (0.28%) S. coagulans. Of the 173 isolates of S. aureus, 25 (52.08%) were positive for the tst gene, which encodes the synthesis of toxic shock toxin. Another 16 (33.33%) were positive for the sea gene, as well as four (8.33%) were positive for see, and one isolate was positive for each of the seb genes (2.08%), sec (2.08 %) and etb (2.08%). All isolates showed lipolytic activity in mesophilic and psychrotrophic conditions, with S. intermedius and S. hycus being highlighted in relation to proteolytic activity. Regarding antimicrobial sensitivity, multidrug resistance was observed in most of the isolates, with clindamycin being the active ingredient with the lowest efficiency (40%), on the other hand, the group of aminoglycosides (gentamicin and streptomycin) was the group with the highest efficiency, being able to inhibit from satisfactorily all the isolates evaluated. It is concluded that the Minas Frescal cheeses, marketed in the northern region of the state of Tocantins, may have a short shelf life due to the deteriorating activity of the evaluated isolates, as well as the evaluated cheeses may pose a risk to consumers, since they presented high counts of ECP and strains with toxigenic potential were isolated.