Lauryl Sulfate Chromogenic Broth 500g Condalab 1465

Lauryl Sulfate Chromogenic Broth is for the detection of total Coliform and E. Coli count at the same time due to the Chromogenic-Fluorogenic Mix. The combination of chromogenic compounds within Lauryl Sulfate Broth provides a double indicator system. It contains a phosphate buffer to ensure the high growth in the total numbers of Coliforms and lauryl sulfate inhibits gram-positive bacteria. Coliforms and E. coli contain ß-galactosidase
which cleaves the chromogenic substrate. 

The enzyme which cleaves MUG is highly specific to E. coli, making the simultaneous detection of total Coliforms and E. coli possible. IPTG stimulates the synthesis and increases the activity of ß-galactosidase. The colour will change from amber to blue-green due to the reaction of the chromogenic substrate which indicates the presence of coliforms. If it has blue fluorescence under the UV light this allows for the rapid detection of E. Coli due to MUG. Tryptophane promotes the indol reaction after adding Kovac’s reagent (Cat. 5205). This reactive detects the microorganism capable of cleaving the
tryptophane. When E. coli is present in the medium, indol is liberated and reacts with 4-dimethylaminobenzaldehyde to form a dark red dye.