Pesquisa de Staphylococcus coagulase negativa em utensílios e queijos mussarela fatiados comercializados em Garanhuns-PE e sua capacidade de formar biofilme

Abstract

Coagulase-negative Staphylococci (CNS) are bacteria found in animal products as contaminants, and also capable of producing biofilms. The objective of this study was to identify CNS species in sliced mozzarella cheeses and cold-cut slicers from bakeries, markets and mini-markets of the city of Garanhuns-PE. Moreover, investigate the ability to form biofilms and the presence of enterotoxin genes sea, seb, sec and sed in the isolated bacteria. Nine bacterial species were identified from a total of 85 CNS isolates, with the most frequent being Staphylococcus (S.) saprophyticus 22 (25.9%), S. xylosus 14 (16.5%) and S. cohnii subsp. urealyticum 7 (8,2%). There was no significant difference between the species found in the samples of Mozzarella cheese and on the surfaces of cold-cut slicers. Of these, 41 (48.2%) were biofilm producers and 44 (51.8%) did not produce biofilms, with the highest detection frequency in S. saprophyticus and S. cohnii subsp. urealyticum. The biofilm producers were also classified as weak producers (61.0%), moderate producers (22.0%) and strong producers (17.0%). Regarding of sea, seb, sec and sed genes, enterotoxin encoders of SEA, SEB, SEC and SED respectively, the presence of these genes was not detected in the isolates. Even with the absence of enterotoxin encoding genes in CNS isolates, these species constitute an important epidemiological source, as they had high counts in the samples, indicating a poor microbiological quality, once they are considered indicators of contamination, it were able to produce biofilms. In addition, several authors have documented the presence of enterotoxin genes in this group of microorganisms. Thus, it can be concluded that the Mozzarella cheeses and the cold-cut slicers of this study were contaminated with CNS producing biofilms and did not carry the classical enterotoxin genes studied. However, the needed to apply good handling and hygiene practices is emphasized, since this bacterial group is an important indicator of the food quality.