A medium detecting β-glucuronidase for the simultaneous membrane filtration enumeration of Escherichia coli and coliforms from drinking water

Abstract

A medium for the single membrane enumeration of Escherichia coli and coliforms from potable water was developed by the modification of the standard UK membrane filtration medium. The medium, membrane‐Lactose Glucuronide Agar (m‐LGA), employs a chromogenic substrate for the detection of β‐glucuronidase activity and sodium pyruvate to enhance recovery of chlorine‐stressed coliforms. Escherichia coli identification was significantly improved on m‐LGA with 98.6% of presumptive isolates confirming. Recovery of coliforms from drinking water samples was also significantly improved.