Environmental distribution of biofilm-forming antibiotic-resistant Escherichia coli associated with plastic surface...

Plastic pollution is now an emerging issue worldwide, and the amount of plastic debris is rapidly increasing day by day in this decade. The surface of plastic contains a wide variety of biofilm-forming microorganisms that can pose a risk to human health. Studies showed that Escherichia coli is resistant to numerous classes of antibiotics; however, the prevalence of the bacterium on the environmental plastic surface is still unknown. The current study aimed at identifying biofilm-forming E. coli from the plastic surface collected from various environmental origins and determining the antibiotic-resistant pattern. A total of 90 plastic samples were collected from wastewater and open surface environments of Mymensingh Medical College, Bangladesh Agricultural University, and BCIC industrial areas of Mymensingh. Among these, 65 samples were found to be positive for the presence of E. coli. The plastic samples collected from drainage sources displayed the highest E. coli prevalence. By targeting the malB gene of the cultured samples, 36 E. coli isolates were positive out of 65, and the prevalence rate was 55.4%. There was a considerable variation in terms of the antibiotic-resistant pattern of the isolates. Randomly, 29 isolates were subjected to an antibiogram study. All of the isolates were resistant to imipenam (100%) and ceftazidime (100%), 79.40% were resistant to ampicillin, and 44.82% resistant to gentamicin. The beta-lactamase-producing genes blaTEM were detected in 51% (14/29) isolates that showed resistance to ampicillin. The biofilm-forming study revealed that 91.16% strong biofilm-forming E. coli isolates were resistant to ampicillin. Additionally, 18.18% non-biofilm-forming tetracycline-resistant E. coli isolates have been found in this study. In summary, to the best of our knowledge, this is the first study in Bangladesh to isolate and identify biofilm-forming antibiotic-resistant E. coli collected from environmental plastic surfaces, but further pathogenicity tests and resistome analysis are required to know the exact genetic resistance pattern.