Ready-to-eat food products procured from different roadside shops in Tiruchirappalli, Tamil Nadu were screened for Escherichia coli. A total of 500 samples from 250 vegetable and 250 meat products were collected from different hotels, restaurants and street food vendors in Tiruchirappalli, Tamilnadu. Out of 500 ready-to-eat food samples, 162 (32.4%) E. coli strains were isolated. The ready-to-eat meat products had higher bacterial count than the vegetable food samples collected due to unhygienic handling, improper storage, inadequate temperature to maintain processed meat and improper cooking. Biochemically identified E. coli colonies were screened for housekeeping gene uidA and 139 (85.8%) E. coli isolates were confirmed to possess β-glucuronidase activity. In addition, antibiotic susceptibility assay was performed using 12 antibiotics. From 139 E. coli strains, 96 (69.1%) isolates showed multidrug resistance. Among them, 16.7% showed 100% resistance to all the antibiotics tested. Whereas, multidrug resistant E. coli isolates showed increased resistance (75.9%) to streptomycin followed by 70-50% level of resistance to ceftriaxone, ampicillin, cefixime, ciprofloxacin, tetracycline, gentamicin, doxycycline, co-trimoxazole, norfloxacin, ofloxacin and chloramphenicol. Furthermore, drug resistant E. coli isolates 56 (58.3%) were detected with the presence of intI1. The source of contamination was found to be water and human handling. Drinking water supply from corporation might have been contaminated with fecal waste source is being discharged into Cauvery river which might disseminate horizontal gene transfer.

The present study was concentrated to screen some members in Enterobacteriaceae family from chilled meat products procured from different retail shops in Tiruchirappalli, Tamilnadu. A total of six varieties of ready to cook chilled food products with five samples in each were randomly purchased from departmental stores, retailer meat shops and local vendors of Tiruchirappalli. Out of 30 ready to cook, chilled food products screened for the presence of Enterobacteriaceae, 28 found to be positive for Enterobacteriaceae. A total of 36 bacterial strains were selected at random and identified. Only 11 isolates were finally confirmed as Enterobacteriaceae and this was shared by Escherichia coli (E. coli), Citrobacter spp., Salmonella spp., Serratia spp. and Proteus spp. Among these Proteus spp. (23.3%) was found predominant in all the samples. Antibiogram study revealed that 54.5% isolates were susceptible to each of Ofloxacin and Ciprofloxacin followed by Ampicillin (45.5%), Chloramphenicol (27.3%) and Gentamycin (18.2%). A high percentage of 54.5% isolates were found to be multidrug resistance (resistant to 3 or more antibiotics). E. coli and Proteus spp. isolated from mixed vegetables and beef respectively, were exhibited 100% resistant to Penicillin, Ciprofloxacin, Chloramphenicol, Ofloxacin, Ampicillin and Gentamycin. The study revealed poor sanitation and cross-contamination in food processing area which resulted in the enhancement of enteropathogenic bacteria which are, known to cause foodborne illnesses. Also, the multidrug resistance noticed in the present study may be linked to the use of antibiotics in cattle rearing which constitute a serious threat to public health.