Pseudomonas spp. are aerobic, gram-negative bacteria that are recognized as major food spoilage microorganisms. A total of 32 (22.9%) Pseudomonas spp. from 140 homemade white cheese samples collected from the open-air public bazaar were isolated and characterized. The aim of the present study was to investigate the biochemical characteristics, the production of extracellular enzymes, slime and β-lactamase, and antimicrobial susceptibility of Pseudomonas spp. isolated from cheeses. The identified isolates including Pseudomonas pseudoalcaligenes, Pseudomonas alcaligenes, Pseudomonas aeruginosa, Pseudomonas fluorescens biovar V, and P. pseudoalcaligenes ssp. citrulli were found to produce extracellular enzymes, respectively: protease and lecithinase production (100%), and lipase activity (85.7, 42.9, 100, and 100%, and nonlipolytic, respectively). The isolates did not produce slime and had no detectable β-lactamase activity. The antimicrobial susceptibility of the isolates was tested using the disk diffusion method. Pseudomonas spp. had the highest resistance to penicillin G (100%), then sulphamethoxazole/trimethoprim (28.1%). However, all Pseudomonas spp. isolates were 100% susceptible to ceftazidime, ciprofloxacin, amikacin, gentamicin, and imipenem. Multidrug-resistance patterns were not observed among these isolates. In this study, Pseudomonas spp., exhibiting spoilage features, were isolated mainly from cheeses. Isolation of this organism from processed milk highlights the need to improve the hygienic practices. All of the stages in the milk processing chain during manufacturing have to be under control to achieve the quality and safety of dairy products.

In the present study, a total of 225 retail meat products (poultry meat, ground beef, and beef samples) were tested for the prevalence of Salmonella. Of these, 50 (22.2%) were positive for Salmonella. Overall, the pathogen was detected in 22 (29.3%) samples of poultry meat (n = 75), 16 (21.3%) samples of ground beef (n = 75), and 12 (16%) samples of beef (n = 75). The most common isolate was Salmonella enterica serovar Typhimurium (9.8%), followed by S. bongori species (8.9%) and S. enterica subsp. diarizonae (3.5%). The Salmonella strains isolated were also examined for antimicrobial resistance patterns and production of β-lactamase enzyme. The resistance levels of the isolates against 14 different antimicrobial agents were tested by the disk diffusion method. None of the strains exhibited resistance to cefotaxime, ciprofloxacin, norfloxacin, or levofloxacin. However, the highest resistance rates in the meat isolates were 64% each for ampicillin and cephazolin and 56% for amoxicillin-clavulanic acid. A total of 62% of the 50 Salmonella strains were multiresistant to three or more antimicrobial agents. The exhibited multiple resistance to four or more antimicrobial drugs was 32%. Furthermore, none of the isolates had β-lactamase enzyme activity.

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In the study, Escherichia coli isolates were recovered from 72 (42.9%) of the 168 retail meat samples. Overall, 48 (66.7%) of the poultry meat, 13 (18.1%) of the ground beef and 11 (15.3%) of the meat samples were positive for E. coli. All E. coli isolates using the disk diffusion method were tested for their resistance patterns toward 16 commonly used antimicrobial agents. In general, the most frequently encountered form of resistance in all samples was resistance to erythromycin (91.7%), tetracycline (55.6%), ampicillin (50%), sulphamethoxazole/trimethoprim (45.8%) and piperacillin (41.7%). None of the isolates had resistance to six antimicrobials tested. A total of 94.4% of the isolates were resistant to one or more antimicrobial agents, and multiple resistance to three or more antimicrobial drugs was 56.9%. Extended‐spectrum beta‐lactamases production in meat isolates was also found in 13.9% of E. coli isolates by the phenotypic confirmatory test and in 11.1% of E. coli isolates by the double disk synergy test. PRACTICAL APPLICATIONS Foodborne diseases are an important cause of morbidity and mortality worldwide, and food safety is an increasingly notable public health issue. The contamination of foods with Escherichia coli may occur in a variety of ways including production, processing, distribution, retail marketing and handling or preparation. Moreover, the increased use of antimicrobial agents in food animal production and human medicine is a significant factor in the emergence of antibiotic‐resistant bacteria. Contamination of food with these bacteria is a threat to public health. This study shows the presence of resistant E. coli in retail meats, and the single and multiple antimicrobial resistance of the strains isolated. It is important because the emergence and development of antimicrobial‐resistant E. coli, as in other bacteria, may be a major public health problem. Recently, extended‐spectrum beta‐lactamase (ESBL) producers pose the challenges to clinical microbiologists, clinicians, antibacterial discoverers, veterinarians and food producers. It may be necessary to monitor the rates of ESBL in food‐related bacteria.