AMERICAN JOURNAL OF ANIMAL AND VETERINARY SCIENCES, cilt.19, sa.2, ss.101-107, 2024 (SCI-Expanded, Scopus)
Coliform bacteria contaminate dairy products and pose
public health concerns including food poisoning and toxemia. We
aimed to determine the species diversity of coliforms and to evaluate
the resistance to antibiotics of E. coli in various types of cheese sold by
local producers in Kazakhstan. We collected 197 samples from
different cheeses sold by producers in the Kostanay (n = 89), East
Kazakhstan (n = 70) and Akmola (n = 38) regions and studied by
classical microbiological and mass spectrometric methods for
contamination with coliforms in certificated for bacterial pathogens’
research laboratories. Such investigation of cheese was experienced
the first time in Central Asia. We isolated five coliform bacteria
species (Escherichia coli, Citrobacter freundii, Serratia liquefaciens,
Enterobacter cloacae and Citrobacter braakii) in 45.2% of the
samples. E. coli and C. freundii were dominant. Antibacterial
resistance of E. coli isolates (n = 65) to 19 antibiotics was investigated
by the disc-diffusion and molecular genetic (PCR) methods. Isolates
were sensitive to drugs of the aminoglycosides group and resistant to
60% of the β-lactams group drugs (ampicillin, cefpodoxime,
cefoperazone) and to an agent out of four of the fluoroquinolones
group (enrofloxacin). Some E. coli strains were multi-drug resistance
to tetracyclines, beta-lactams and fluoroquinolones. PCR of E. coli
isolates revealed genes that encoded the resistance to β-lactams in
15.4%, to sulfonamides in 30.8% and quinolones in 9.3% of cheese
samples, providing sufficient biotic potential for the transfer of these
genes to intestinal biocenosis bacteria of humans.