Monitoring microbial contamination of antibiotic resistant Escherichia coli isolated from the surface water of urban park in southeastern Brazil

Abstract Contamination of water resources through anthropic activities can alter water quality. The objective of this study was to monitor the presence and concentration of Escherichia coli in the water of Carmo Park - SP and evaluate the antibiotic resistance of E. coli isolated from water. Three collection points were analyzed and identified as: P1 – Stream with preserved riparian forest that supplies the main lagoon, P2 - Secondary lagoon without ciliary vegetation that also supplies the main lagoon and P3 - Main lagoon without ciliary vegetation. Environment and water temperature were measured by portable digital thermometer. The pH was determined by bench pH meter. The concentration of E. coli was performed by inoculating the samples in 3 MTM PetrifilmTM plates incubated at 37 °C for 48 hours. The isolates were sown in Petri dishes containing Agar Mueller Hinton and the disc diffusion technique was used to evaluate the profile of susceptibility to antibiotics. The water of Carmo Park has concentrations of E. coli that fall within the limits allowed for class 2 water bodies. This water is suitable for bathing and its rating varies from very good to excellent. The seasons are related to the concentration of these bacteria in water, because in rainy periods the concentration of E. coli increases due to the surface flow that allows the entry of these microorganisms into the water. E. coli isolated from water are more resistant to amoxicillin, erythromycin and tetracycline.