SIM Medium (Dehydrated)

Differentiate enteric bacteria on the basis of sulphide production, indole production and motility with Thermo Scientific™ Oxoid™ SIM Medium (Dehydrated). The medium contains sodium thiosulphate and ferrous ammonium sulphate, which together act as indicators for the production of hydrogen sulphide. Tryptone incorporated into the medium is a tryptophan-rich peptone and is degraded by specific bacteria to produce indole. The use of 0.35% agar in the medium results in the production of a semi-solid medium, ideal for the examination of motility.

A motility-indole medium has been found to be helpful in the identification of the Enterobacteriaceae; e.g. in the differentiation of Klebsiella from Enterobacter and Serratia species¹. For convenience, these two important tests have been combined with sulphide-production in one tube. The production of hydrogen sulphide is a useful diagnostic test in the identification of enteric bacteria and is helpful in the differentiation between Salmonella and Shigella.

Typical reactions of organisms in SIM medium: