Use Azide Blood Agar Base for detection and isolation of streptococci and staphylococci from feces, sewage and other specimens containing mixed flora.

• Selective: sodium azide in the medium has a bacteriostatic effect on most Gram-negative organisms but permits growth of Gram-positive organisms such as streptococci and some strains of staphylococci. Proteus species are slightly more resistant than other Enterobacteriaceae but swarming is prevented (Snyder and Lichstein¹, Lichstein² and Snyder³).
• Recommended by the American Public Health Association⁴ for the isolation of streptococci from cheese.
• Can be used for the simultaneous determination of hemolytic reactions.

There are variations in formula of Azide Blood Agar Base which have been recommended for different purposes:

1. Packer⁵ increased the sodium azide concentration to 0.9g per litre and added 0.002g per litre of crystal violet. The pH was also adjusted to 6.8 ± 0.1. This is a more selective medium for fecal streptococci in foods⁶.
2. Packer⁵ and Wood⁷ used the above formulation with 5% blood and crystal violet increased at 0.01g per litre, for the isolation of Erysipelothrix rhusiopathiae and Streptococcus pneumoniae.
3. Dale⁸ and Bohm⁹ recommended the addition of phenol (1.0 to 2.5g per litre) to Packer's formulation to isolate Erysipelothrix rhusiopathiae.

Not all products are available for sale in all territories. Please inquire.

Remel™ and Oxoid™ products are now part of the Thermo Scientific brand