merck coliform agar 500 gr 1104260500

Ordering number: 1.10426.0500 For the simultaneous detection of coliform bacteria and E. coli in drinking water, waters with low bacterial background flora and processed food samples. Drinking water and waters with low bacterial background: This culture medium complies with the specifications given by EN ISO 9308-1. Chromocult Coliform Agar membrane filter method has been approved and accepted by the U.S. Environmental Protection Agency (EPA) for monitoring total coliform bacteria and E. coli under the Total Coliform Rule (40 CFR 141.21). Processed food: Chromocult Coliform Agar acc. ISO 9308-1 (CCA) has been validated by the AOAC Research Institute under the Performance Tested MethodsSM program for the analysis of frankfurters, cooked chicken and non-fat dried milk. Mode of Action The interaction of selected peptones, pyruvate, sorbitol and phosphate buffer promotes rapid colony growth, even for sub-lethally injured coliform bacteria. The growth of Gram-positive bacteria as well as certain Gram-negative bacteria is inhibited by the presence of Tergitol7 which has no negative effect on the growth of coliform bacteria. Further, the combination of two chromogenic substrates permits the simultaneous detection of coliform bacteria and E. coli. Coliform bacteria detection: The substrate Salmon-GAL is used for the detection of β-D-galactosidase activity, which is characteristic for coliform bacteria. This interaction results in a pink to red color of the coliform colonies. E. coli detection: The substrate X-glucuronide is used for the detection of β-D-glucuronidase activity, which is characteristic for E. coli.