Double Modified Lysine Iron Agar Base

Double Modified Lysine Iron Agar Base is recommended for selective and differential cultivation of Salmonella species.It is used to for isolation and identification of Salmonella from food. Cultures that produce hydrogen sulphide cause blackening of the medium due to ferrous sulphide production. Lysine decarboxylation causes an alkaline reaction (purple colour) to give the amine cadaverine and the organisms which do not decarboxylate lysine, produce acid butt (yellow colour). Organisms that deaminate lysine, form a - ketocarboxylic acid, which reacts with iron salt near the surface of the medium under the influence of oxygen to form reddish-brown compound.