Differential medium for identification of enteric bacteria based on fermentation of dextrose, lactose and H2S production. This medium permits differentiation of Gram-negative bacilli by their ability to ferment Dextrose or Lactose, and produce hydrogen sulfide. Enzymatic Digest of Casein and Enzymatic Digest of Animal Tissue provide nitrogen, carbon, and vitamins required for organism growth. Ferric Ammonium Citrate and Sodium Thiosulfate are indicators of hydrogen sulfide production. Phenol Red is the pH indicator. Sodium Chloride maintains the osmotic balance of the medium. Agar is the solidifying agent.
Formulation (g/L):Enzymatic Digest of Casein 10Enzymatic Digest of Animal Tissue 10Lactose 10Dextrose 1Ferric Ammonium Citrate 0.5Sodium Chloride 5Sodium Thiosulfate 0.5Phenol Red 0.025Agar 15Total:52g/L
Directions per Liter:1. Suspend 52g of the medium in one liter of ddH2O
2. Heat with frequent agitation and boil for one minute to completely dissolve the medium
3. Distribute into test tubes and autoclave for 15 minutes at 121°C
4. After autoclaving, allow medium to solidify in a slanted position.
Storage and Stability:Store sealed bottle containing the dehydrated medium at RT. Once opened and recapped, place container in a low humidity environment at the same storage temperature. Protect from moisture and light.
Solubility: Reddish-orange to red, trace to slightly hazy
pH (5.2%): 7.4
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.
