-
Originally introduced as an aid to recovery of Shigella spp. XLD is also a first class medium for recovery of Salmonella spp. It differs from other media of this type in that it has less Sodium Desoxycholate as its selective agent. The indicator system is somewhat complex taking advantage of the fermentation or otherwise of three carbohydrates (Lactose Sucrose and Xylose) together with Lysine Decarboxylase and Sodium Thiosulphate as an indication of the presence or absence of Hydrogen Sulphide. -
This is a selective medium for the isolation and enumeration of Yersinia spp. in clinical and food samples. It is made selective by the inclusion of Sodium desoxycholate, Crystal violet and the antimicrobials Cefsulodin, Novobiocin and Irgasan. Mannitol is also included which Yersinia ferments giving a colony that produces a ‘Bull’s Eye’ appearance. The majority of other enteric organisms are inhibited but if they do grow they produce a large pinkish colony with an opaque halo.
