Detection and Identification of Tetracycline-Resistant E.Coli Isolated from Ready to Eat Vegetables
Background: There have been rising outbreaks of food infections which are associated with Ready to Eat (RTE) vegetables consumption. Recently, antimicrobial resistance in human becomes a worldwide problem. Antibacterial resistance such as to agent like tetracycline inhibits the prevention and effective treatment to infectious diseases. Therefore, it is important to detect characteristics of tetracycline-resistant Escherichia coli isolated from RTE vegetables.
Objectives: This study aimed to isolate tetracycline resistant E. coli from Ready to Eat Vegetables and also determine its resistance to other common antibiotics.
Materials and Methods: The study took place in Microbiology Laboratory, University of Brawijaya, Malang City, Indonesia. A total of forty-eight samples (Lettuce, Lemon basil, Yard long bean and Cabbage) were collected from five different places (Pasar Besar, Pasar Belimbing, Giant supermarket, Lai Lai supermarket and Loka supermarket). Subsequently, using media of Eosin Methylene Blue Agar which was supplemented with 15mg/ml of Tetracycline, these samples were analyzed to detect the presence of tetracycline-resistant E. coli. Identification and characterization of E. coli isolates were performed using a biochemical test followed by PCR to detect 16S rRNA and antibiotic resistance of the isolates in disk diffusion.
Results: Eighteen samples (37.5%) showed a positive result of the present of E. coli resistant to antimicrobial tetracycline. This included 6 isolates from Lettuce, 8 isolates from Basil, 3 isolates from Yard long bean and 1 isolate from Cabbage. The higher number of tetracycline resistant isolates was recorded in the samples from Pasar Besar and Pasar Belimbing while the lower number was recorded in the samples from LOKA supermarket.
The results indicated that 18 isolates (100%) were resistant to one or more antimicrobials. Moreover, the highest levels of resistance were observed for tetracycline and streptomycin by 100%, followed by Kanamycin by 77.8%. Mere 11.1% and 5,6 % isolates were resistant to Chloramphenicol and Ciprofloxacin.
Conclusion: To sum up, this study showed that 37.5% of RTE vegetable samples contained tetracycline resistant E. coli in and the isolates highly resistant to tetracycline and streptomycin (100%) could be hazardous for public health.
Keywords - E.coli, Multidrug resistance, Ready to Eat Vegetables, tetracycline.