The first chromogenic culture medium (for detection ofE. coli) was invented and patented by Dr Alain Rambach in 1979. The introduction of this medium triggered a revolution in microbial diagnosis driven by the introduction of a whole range of media for the detection of key clinical & food borne pathogens.
How does Chromogenic Culture Media technology work?
The power of chromogenic technology is the combination of the detection of precise enzyme activity and localized staining precipitating in the colony, allowing an easy differentiation of microorganisms thanks to the coloration of grown bacteria.
This technology is based on soluble colorless molecule called chromogen, composed of a substrate, targeting a specific enzymatic activity and a chromophore.
When the target organism’s enzyme cleaves the colorless chromogenic conjugate, the chromophore is released. In its unconjugated form, the chromophore exhibits its distinctive color and, due to reduced solubility, forms a precipitate.
The result is a very specific & distinctive color-based differentiation, which is clearly distinguishable to the naked eye under normal lighting conditions.