Costein’s LDS Test Medium 500G

Costein’s LDS Test Medium is recommended for identification of members of Enterobacteriaceae on the basis of lysine decarboxylase (LDC) and hydrogen sulphide (H2S) production. LDC-negative and H2S negative organisms show yellow coloured growth e.g. Citrobacter, Proteus vulgaris, Proteus mirabilis, Providentia, Enterobacter, Shigella. LDC-positive and H2S positive organisms give black colour and may be surrounded by a violet zone e.g. Salmonella, Edwardsiella and others. LDC-positive and H2S negative organism are violet in colour  e.g. Escherichia, Klebsiella, Hafnia, Serratia and some rare Salmonella and others.