XLD Agar
Overview
Xylose lysine deoxycholate (XLD) agar detects gastrointestinal pathogens, including Salmonella spp. and Shigella spp. by inhibiting gram-positive bacteria, allowing gram-negative bacteria to grow. Xylose is fermented by most enteric bacteria, producing acid that turns the medium yellow. Bacteria that decarboxylate lysine create an alkaline environment, resulting in red colonies. Salmonella spp. produces hydrogen sulfide (H2S), forming black colonies when it reacts with iron salts in the medium. XLD agar is used mainly to isolate Salmonella spp. and Shigella spp. from clinical and environmental samples, including stool. Yellow colonies indicate xylose fermentation (e.g., E. coli), red colonies show lysine decarboxylation without xylose fermentation, and black colonies suggest H2S production, typical of Salmonella spp. Further microbiological identification tests are necessary to confirm and diagnose the presence of microorganisms.
Intended Use
For moderately selective and differential solid medium for the isolation of gram-negative enteric pathogens.
Product Information
Category
Catalog Number
FP90X1001, FP90X1002
Pack Size
10 per pack