LYSINE IRON AGAR

Lysine Iron Agar was developed by Edwards and Fife to detect lactose fermenting Salmonellae. Salmonellae are known to decarboxylate lysine rapidly and produce large amounts of hydrogen sulphide. This medium is a sensitive medium for the detection of lactose fermenting and lactose non fermenting Salmonella species. Many strains of this group ferment lactose very rapidly thus suppressing H2S production on Triple Sugar Iron Agar. So there is a possibility that the organisms frequently found in food poisoning outbreaks could be overlooked. Thatcher and Clark described the isolation of Salmonella species from foods from selective agar and to inoculate it on Lysine Iron Agar and Triple Sugar Iron together. Using these two media greater discrimination can be made between coliform organisms e.g. Escherichia coli and Shigella species. HENNER et al. (1982) reported that Lysine Iron Agar is superior to other comparable culture media for differentiating between Proteus and Salmonella.

for di?erentiation of enteric organisms especially Salmonella species based on their ability to decarboxylate or deaminate lysine and production of H2S