Profiling of meropenem-resistant bacteria in a river receiving wastewater effluent from a pharmaceutical industrial unit

The aim of the present study was to understand the seasonal occurrence and diversity of species of meropenem-resistant bacteria in the Gumuncheon river receiving effluents from a pharmaceutical industry in Seoul, Korea.Water samples were collected from the Gumuncheon river in Kyoung-gi province during winter (January), spring (April), summer (August), and fall (November) of 2018. Water samples were plated in triplicate on tryptic soy agar plates containing 16 mg/L meropenem. Meropenem-resistant bacteria were isolated and genetically identified using 16S rRNA analysis. The predominant bacterial genera identified were Elizabethkingia, Pseudomonas, Chryseobacterium and Stenotrophomonas. Among these; Pseudomonas species Pseudomonas chengduensis and Pseudomonas taiwanesis showed resistance against 15 antibiotics. To prevent the occurrence and spread of meropenem-resistant bacteria in rivers, it is necessary to implement methods that can simultaneously kill multi-drug resistant bacteria and remove antibioticsfrom pharmaceutical industry effluent discharge. Further, to stop the spread of meropenem-resistant bacteria in environment, effluent discharge water should be stringently assessed for their risk of being an environmental hazard.