Description

Lysine Iron HiVeg™ Agar is recommended for differentiation of enteric organisms especially Salmonella arizonae, based on their ability to decarboxylate or deaminate lysine and to form hydrogen sulphide (H₂S). Dextrose is a source of fermentable carbohydrate. Ferric ammonium citrate and sodium thiosulphate are indicators of H2S formation. 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). Lysine Iron HiVeg™ Agar is prepared by using vegetable peptones in place of animal based peptones which make the media free of BSE/TSE risks.