Harlequin™ Chromogenic Coliform Agar

Informacija apie produkta

Chromogenic Coliform Agar (CCA) is recommended by ISO 9308-1 for the simultaneous detection and enumeration of β-glucuronidase-positive Escherichia coli and β-D-galactosidase positive coliform bacteria using membrane filtration from water samples.

Peptone and yeast extract provide a source of nitrogen and essential vitamins. Sodium chloride maintains the osmotic balance and the phosphates buffer the media. Sodium Pyruvate, Sorbitol and Tryptophan aid in the recovery and detection of the target organisms.

Tergitol™ 7 is a surfactant that acts as a selective agent. The dual chromogens are incorporated to visualise enzyme expression. IPTG induces β-D-galactosidase and agar is the gelling agent. E.coli possess both β-D-galactosidase and β-glucuronidase activity so appear dark blue to violet. Coliform bacteria, that are not E.coli, possess only β-D-galactosidase so appear pink to red. Any organism able to grow that does not belong to these groups appears colourless.

This medium conforms to the performance requirements of ISO 9308-1 2017.