S.S. Agar Bioprepare 100ml

S.S Agar is a selective and differential medium for the isolation of pathogenic enteric bacteria, particularly Salmonella and Shigella, from food and other specimens. In S.S. Agar the beef extract and the Balanced Peptone No. 1 provide nitrogen, vitamins, metals and amino acids necessary for the growth. When lactose is fermented, it becomes a source of carbon and energy. The mixture of Bile Salts No. 3, Sodium citrate and Brilliant Green inhibit the Gram (+) positive bacteria, most Coliforms and some Proteus spp allowing the growth of Salmonella spp at the same time. Neutral Red is the pH indicator. Sodium thiosulphate and Ferric citrate enable the detection of H2S that produce bacteria, like Proteus and some Salmonella versions, as they form colonies with black centres and a clear halo. The bacteria that do not ferment lactose (so-called pathogens) form clear colonies, transparent or colourless, while Coliforms are adequately inhibited and form small colonies that vary from pink to red in colour. This composition is particularly selective and it is not recommended for the primary isolation of Shigella. Some Shigella spp versions may not grow. Available in a bottle of 100ml and stored at 6-12°C.