Occurrence, Molecular Characterization and Antimicrobial Assay of Escherichia coli Isolates from Milk and Milk Products

Abstract

The present study was conducted to examine the occurrence of E. coli in milk and milk products and their characterization. A total of 300 samples of milk and milk products were screened from different areas in Jabalpur. The bacteria were isolated and characterized biochemically, genotypically and on the basis of antimicrobial profile. Out of 300 samples of milk and milk products, 24.0% (n=72) were found positive for E. coli. The incidence of E. coli in milk and ice cream was 30.0% and 27.0%, respectively while none of the shrikhand samples showed E. coli presence. Molecular study revealed 70.8%, 11.1% and 20.8% uspA, stx1 and stx2 gene, respectively in the E. coli isolates. Results of antimicrobial susceptibility test of E. coli showed that isolates were sensitive to ofloxacin (100.0%), netilin (88.8%), ciprofloxacin (85.1%), norfloxacin (81.4%), ceftazidime (66.6%), streptomycin, chloramphenicol and tetracycline (62.5%), cefotaxime and nalidixic acid (55.5%), gentamicin (52.5%) and kanamycin (50.0%) but resistant to nitrofurantoin (66.6%), ampicillin (52.5%), amikacin (40.0%) and co-trimoxazole (37.5%). The presence of zoonotic E. coli along with multidrug strains in the milk and milk products may lead to food borne and systemic infections therefore; the sanitary quality should be maintained while handling food products