Lab M's range of microbiological culture media includes a specialist chromogenic medium for the simple enumeration of E coli in conjunction with ISO 16649-1:2001 or other standard methods.
The Harlequin TBGA (Tryptone Bile Glucuronide Agar) medium features a chromogenic substrate that detects the beta-glucuronidase enzyme that is highly specific to E coli.
Since the chromogenic reaction is concentrated within the bacterial colony, enumeration when large numbers are present or in the company of other organisms is straightforward.
All blue colonies are counted as presumptive E coli, with confirmation requiring just a simple indole test.
