Banca de QUALIFICAÇÃO: Letícia Fernandes Silva Rodrigues

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : Letícia Fernandes Silva Rodrigues
DATE: 14/02/2023
TIME: 14:00
LOCAL: on line (Teams)
TITLE:

Profile of antimicrobial resistance of Escherichia coli and Staphylococcus aureus bacteria isolated from artisanal cheese sold in the Federal District

KEY WORDS:

Antimicrobial resistance. Food quality. Artisanal cheese. Escherichia coli. Staphylococcus aureus.

PAGES: 46
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

Introduction: Considering that cheeses have a production process with several handling steps, they provide conditions for the multiplication of potentially pathogenic microorganisms, such as Escherichia coli and Staphylococcus aureus. In the Federal District, artisanal cheeses are sold at permanent fairs and do not have characteristics that establish minimum standards of food safety, such as the date of manufacture and expiration, description of the origin of the product and inspection seals. Objectives: Thus, this work aims to evaluate the microbiological quality of artisanal cheeses sold at permanent fairs in the Federal District, with emphasis on molecular confirmation of virulence and resistance genes for E. coli and S. aureus bacteria isolated from these cheeses . Materials and methods: Samples of artisanal cheeses (Minas Frescal and Coalho) were collected from different permanent fairs in the Federal District. The microbiological analyzes were: total count of mesophilic and psychrotrophic microorganisms, determination of the Most Probable Number of total coliforms and thermotolerant coliforms, S. aureus count and Salmonella spp. Strains of E. coli and S. aureus isolated from cheeses were subjected to antimicrobial susceptibility testing using the disk diffusion technique (Kirby-Bauer technique). Finally, genotyping was performed using the polymerase chain reaction technique to confirm the virulence genes and antimicrobial resistance genes of the microorganisms E. coli and S. aureus. Partial results: In total, 91.7% (22/24) of the artisanal coalho cheese samples analyzed in this study were unfit for consumption according to Brazilian legislation, as they exceeded the acceptable limit for thermotolerant coliforms and/or S. aureus . From the analysis of 24 samples of coalho cheese, 23 strains of E. coli and 37 strains of S. aureus were isolated. E. coli strains showed greater resistance to sulfonamide (82.61%), cefotaxime (47.83%), ciprofloxacin and gentamicin (39.13%). S. aureus strains showed greater resistance to sulfonamide (86.49%), cefoxitin (78.38%) and gentamicin (48.65%). From the 22 samples of artisanal Minas Frescal cheeses, 104 strains of E. coli and 135 strains of S. aureus were isolated. E. coli strains showed greater resistance to sulfonamide (85.58%), tetracycline (32.69%), followed by ciprofloxacin (23.08%). S. aureus strains showed greater resistance to sulfonamide (71.85%) and cefoxitin (36.30%), followed by tetracycline (20.00%). Considering resistance to cefoxitin equivalent to resistance to oxacillin, 36.30% of strains can be classified as MRSA. Multidrug resistance rates of 33.65% (35/104) in E. coli strains and 20.00% (27/135) in S. aureus strains were obtained.

BANKING MEMBERS:
Externa à Instituição - VANIA SILVA CARVALHO - IFGOIANO
Externa à Instituição - CALLIANDRA MARIA DE SOUZA SILVA - UnB
Presidente - 1697332 - DANIELA CASTILHO ORSI
Externa ao Programa - 1750177 - LIVIA CRISTINA LIRA DE SA BARRETO