KF (Kenner Fecal) Streptococcus Agar is used with TTC Solution 1% in isolating and enumerating fecal streptococci.

Note TTC Solution 1% not included - sold separately.

Principles Peptone provides a source of nitrogen, amino acids and carbon. Yeast extract is a source of trace elements, vitamins and amino acids. Maltose and lactose are fermentable carbohydrates and carbon sources. Sodium azide is a selective agent. Bromcresol purple is an indicator dye.

In this medium, the addition of 1% triphenyltetrazolium chloride (TTC) causes enterococci to develop a deep red color. TTC is used as a redox indicator in culture media. It is colorless in the oxidized form and is reduced to formazan, an insoluble red pigment, by actively growing microbial cells. The reduction of TCC is irreversible; it is not reoxidized by air once it is reduced to the red formazan.