SKU: sku-2567
For selective isolation and enumeration of Salmonella typhi and other Salmonella species.  XLD  Agar  was  formulated  by  Taylor  for  the  isolation  and  differentiation  of  enteric  pathogens including Salmonella  Typhi from other  Salmonella species. XLD Agar has been recommended for the identification  of Enterobacteriaceae  and  for  the  microbiological  testing  of  foods,  water  and  dairy products. The media formulation does not allow the over growth of other organisms over Salmonella and Shigella.    The  medium  contains  Yeast  extracts  as  source  of  vitamins  and  minerals.  Addition  of  Sodium deoxycholate acts as a selective agent which is inhibitory to Gram-positive bacteria. It suppresses the growth of other enteric pathogens and enhances the growth of only few enteric bacilli. The medium contains Xylose as a fermentable carbohydrate which is utilized by Salmonella species. The medium pH is changed due to fermentation of Xylose which is detected by indicator Phenol red, thus the colony colour turns red. The medium also contains Lactose and Sucrose as the source of fermentable sugar.  L-lysine  is  an  essential  amino  acid  source.  Lysine  is  added  to  differentiate Salmonella  Sp.   Sodium  chloride  helps  maintaining  the  osmotic  balance  of  the  cells.  This  medium  also  allows differentiation of bacilli based on their ability to produce H2S; it contains Sodium thiosulphate and Ferric  ammonium  citrate  that  helps  visualizing  the  black  centered  colonies  on  production  of hydrogen sulphide in the medium. Agar is added as the solidifying agent.
Product Code: 
TM 492
Technical Data: