Baird-Parker agar is a type of agar used for the selective isolation of gram-positiveStaphylococci species.[1] It contains lithium chloride and tellurite to inhibit the growth of alternative microbial flora, while the included pyruvate and glycine promote the growth of Staphylococci.[1]Staphylococcus colonies show up black in colour with clear zones produced around them.[1]
History
Baird-Parker Agar From Liofilchem first published an academic article about this agar medium for the purposes of improved diagnostics and isolating coagulase-positiveStaphylococci in 1962.[2] He developed this agar medium from the tellurite-glycine formulation of Zebovitz et al[3] and improved its reliability in isolating coagulase-positive staphylococci from foods. Baird-Parker added egg yolk emulsion as a diagnostic agent and sodium pyruvate to protect damaged cells and aid their recovery.[4] It is now widely recommended by national and international bodies for the isolation of coagulase-positive staphylococci.[5] Baird-Parker agar is commonly used as a method for the enumeration of coagulase-positive staphylococci (Staphylococcus aureus and other species) in food and animal feedstuffs.[6]