Baird Parker Medium
Baird Parker medium is used for isolation and enumeration of coagulase positive Staphylococci species in food and pharmaceutical samples1. Baird-Parker medium was developed by Baird-Parker and the present formulation is developed by Zebovitz et al2, 3. Sodium pyruvate and glycine were added as selective growth stimulants, egg yolk emulsion as a differentiation agent. The selectivity of the medium is maintained by the addition of Lithium chloride and Potassium Tellurite which suppress the growth of the accompanying flora except Staphylococci sp. The medium allows growth of Staphylococcus aureus and selectively inhibits growth of most other bacteria. Glycine and pyruvate are added to enhance the growth of staphylococci. Staphylococci that contain lecithinase break down the egg yolk and form clear zones around the colonies. Black colonies are formed due to reduction of the Potassium tellurite to tellurium. Black, shiny, and convex S. aureus colonies are surrounded by a clear zone of ~2 - 5 mm in diameter. Some other micro-organisms, which occasionally grow on this medium, are micrococci which form small dark colonies, yeasts which form white colonies and some species of Bacillus which form dark brown matte colonies.
|Product Name||Catalog #||Quantity|
|Baird Parker Agar mono plate, 90 x 15 mm||CB9120P||10/pk|
|Baird Parker Slant||CB9120S||10/pk|
The following organisms are routinely used for testing for this medium.
|Proteus mirabilis ATCC® 12453||Growth; brown colonies|
|Escherichia coli ATCC® 25922||Partial to complete inhibition|
User Quality Control
Check for signs of contamination and deterioration. Users of commercially prepared media may be required to perform quality control testing with at least one known organism to demonstrate growth or a positive reaction; and at least one organism to demonstrate inhibition or a negative reaction (where applicable).
Ingredients g/L(Final pH 7.0 +/- 0.2 at 25°C)Pancreatic Digest of Casein10.0
|Egg Yolk Tellurite Enrichment (mL)||60.0|
|Agar (where applicable)||20.0|
3 total citations
- Association of Official Analytical Chemists. 2012. Official Methods of Analysis, 19th ed. AOAC, Washington, D.C
- Baird-Parker. 1962. J. Appl. Bact.; 25:12.
- Zebovitz, Evan, et al. 1955. J. Bact.; 70:686.