Caracterização genotípica de staphylococcus aureus e salmonella sp. isoladas de linguiça artesanal

• Ano de defesa: 2020
• Autor(a) principal: Costa, Maria Gabriela Alves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Semi-Árido; Brasil; Centro de Ciências Agrárias - CCA; UFERSA; Programa de Pós-Graduação em Produção Animal
• Palavras-chave em Português: Doenças transmitidas por alimentos; Staphylococcus aureus; Salmonella sp; Genótipo; Linguiça artesanal; Foodborne diseases; Genotype; Artisanal sausage; CIENCIAS AGRARIAS::ZOOTECNIA
• Link de acesso: https://repositorio.ufersa.edu.br/handle/prefix/5451

Staphylococcus aureus and Salmonella sp. are bacteria involved in outbreaks of foodborne diseases since they cause gastroenteritis as systemic infections. The objective of the work is to identify the presence of strains of Staphylococcus aureus and Salmonella sp., as well as to characterize these microorganisms in terms of their virulence and resistance genes in artisanal sausage isolates in the state of Rio Grande do Norte. For the work, a total of 50 samples of artisanal sausage were collected (30 from company A and 20 from company B) and a microbiological analysis for S.aureus and Salmonella sp. After performing biochemical tests and isolating the strains, the samples were subjected to Polymerase Chain Reaction (PCR) to identify species (Staphylococcus aureus and Salmonella sp.), presence of enterotoxins, antibiotic resistance genes, virulence genes , sanitizing resistance genes, biofilm formation. In addition, an antibiogram was performed for both species. For Staphylococcus aureus of the 16 strains that presented positive coagulase, 8 strains were positive for the nuc gene. Of these 8 strains, 3 isolates had enterotoxin genes (sea, sec, sei), whereas for resistance genes only one strain had the mecA gene. The regulatory genes agr in the present study obtained 6 strains with agrI and 2 strains with agrIII, the strains of S.aures did not show genes for resistance to sanitizers and presented the icaA and icaD genes for biofilm formation. In the antibiogram, 88% of S.aureus isolates showed resistance to oxacillin. For Salmonella sp, of the 75 strains analyzed, 49 showed serology and positive color for the species. Of these, 34 isolates obtained the invA gene. The 34 were submitted to virulence genes, such as: ssaR, sipB, sipA, sifA, sopB, sipD, sopD. The isolated Salmonella strains had at least two virulence genes from those tested in the study. These strains came from the mixture before filling and the sausage was ready. For the antibiogram, 35% of Salmonella strains showed resistance to tetracycline. It is concluded that there is a need for more attention to food safety, since a large number of pathogenic microorganisms and virulence and resistance genes were found, as well as measures in companies and in the State to carry out adjustments that guarantee a product with good quality to the consumer.