The resistance of Gram-negative bacteria to β-lactam antibiotics occurs mainly by the production
of β-lactamases. The aim of this work was to evaluate the presence of β-lactamase genes and
integrons in multidrug-resistant (MDR) isolates recovered from food. Susceptibility to antibiotics
was determined using the agar diffusion method. Detection of β-lactam resistance genes and
integrons was performed with the 53 confirmed MDR strains (42 E. coli and 11 Salmonella spp.) by
PCR. High resistance rates of 92.5 %, 60.4 %, and 54.7 % against ampicillin, tetracycline, and
amoxicillin/clavulanic acid were observed, respectively. Two β-lactamase genes blaTEM (37.7 %)
and blaSHV (28.3) were detected among E. coli and Salmonella isolates. High rate of isolates (85 %)
exhibited class 1 integrons was observed. These isolates can act as sources of antimicrobial
resistance genes and promote the spread of these resistance determinants to other commensal and
pathogenic bacteria. Therefore, preventive measures and clean environments are recommended
to prevent food contamination with resistant microorganisms.

E. coli, Salmonella spp., Antimicrobial resistance genes, Integron, FOOD