Baird-Parker Agar is one of the essential agar media utilized in microbiology laboratories. Its wide application and reliability have made Baird-Parker Agar a valuable tool in microbiological analysis and quality control. In this article, we explore its principle, its preparation, its interpretation and its different uses.
Baird-Parker Agar, introduced by Baird-Parker (1962), serves as a medium for counting Staphylococcus aureus in various food sources. This moderately selective and differential medium is used to isolate and quantify Staphylococcus aureus from food, environmental and clinical samples.
Colonies of Staphylococcus aureus are black and shiny, with a thin white border, surrounded by a light area.
Staphylococcus aureus on Baird Parker
Baird Parker agar composition
|Ingredients||gram / liter|
|Pancreatic digestion of casein||10.0g|
|pH||7.2 ± 0.2|
Dehydrated Baird Parker Agar
Baird Parker Agar contains casein peptone, beef extract and yeast extract as sources of nitrogen, carbon, sulfur, vitamins and trace elements.
Baird Parker Agar
This culture media can also be used to detect coagulase activity by adding fibrinogen plasma
Staphylococcus aureus is characterized by the formation of black, shiny, convex colonies surrounded by a lightening halo of the egg yolk. Coagulase negative staphylococci are almost completely inhibited and if, however, a culture does appear, areas of thinning would be absent.
- In principle, other microorganisms are inhibited. However, it is possible to observe brown or greenish colonies of micrococci, white colonies of yeast, brown colonies of Bacillus or Proteus.