SS平板原理及反应

For the isolation of salmonellae and shigellae from faeces, foodstuffs and other materials.

Brilliant green, ox bile and high concentrations of thiosulfate and citrate largely inhibit the accompanying microbial flora. Sulfide production is detected by using thiosulfate and iron ions, the colonies turn black. The presence of coliform. bacteria is established by detecting degradation of lactose to acid with the pH indicator neutral red.

The plates are clear and reddish-brown.

Lactose-negative colonies are colourless. Lactose-positive colonies are pink to red. Colonies of microorganisms producing H2S have a black centre.