Evaluation of Polymerase Chain Reaction for Detecting Coliform Bacteria in Drinking Water Sources

Coliform bacteria are used as indicator organisms for detecting fecal pollution in water. Traditional methods including microbial culture tests in lactose‑containing media and enzyme‑based tests for the detection of β‑galactosidase; however, these methods are time‑consuming and less specific. The aim of this study was to evaluate polymerase chain reaction (PCR) for detecting coliform.

Totally, 100 of water samples from Isfahan drinking water source were collected. Coliform bacteria and Escherichia coli were detected in drinking water using LacZ and LamB genes in PCR method performed in comparison with biochemical tests for all samples.

Using phenotyping, 80 coliform isolates were found. The results of the biochemical tests illustrated 78.7% coliform bacteria and 21.2% E. coli. PCR results for LacZ and LamB genes were 67.5% and 17.5%, respectively.

The PCR method was shown to be an effective, sensitive, and rapid method for detecting coliform and E. coli in drinking water from the Isfahan drinking water sources.