KM0037 – Baird Parker Agar

//KM0037 – Baird Parker Agar

KM0037 – Baird Parker Agar

Baird Parker agar is a selective medium for the isolation and presumptive identification of coagulase-positive staphylococci. This medium is used extensively for detecting Staphylococcus aureus in foods, dairy products, and other materials.
Enzymatic digest of casein, meat extract and yeast extract provide the required carbon, nitrogen and vitamins. The medium is made selective by the inclusion of lithium chloride and the addition of potassium tellurite. Glycine and sodium pyruvate are included as growth enhancers while the pyruvate also acts as a neutraliser of toxic peroxides.
Coagulase positive staphylococci are differentiated by the addition of egg yolk tellurite (BM0530) due to their ability to break down the egg yolk. Clear zones around colonies form due to the
proteolytic action of lecithinase. A secondary opaque zone,
surrounding presumptive positive colonies, may also form due to lipase activity. Potassium tellurite is reduced by staphylococci giving rise to blackening of colonies.
NB: Any black colonies (with halo (typical) or without the halo (atypical)) on this medium must be confirmed as Staphylococcus aureus by further tests (e.g. coagulase test or latex agglutination etc.)

Related Supplements :
BM0530 Egg Yolk Tellurite

SKU: KM0037 Category:

Additional Information

Shelf Life (days)

Storage Temp (°C)

Dehydrated Medium Appearance

Prepared Medium Appearance

Dehydrated Medium Colour

Prepared Medium Colour

Dehydrated PH

Prepared PH

Product Description

Organisms Ref. No Result
Staphylococcus aureus NCTC 12981 Growth, black colonies with clear halo
Staphylococcus epidermidis NCTC 13360 Inhibited
Escherichia coli NCTC 12241 Inhibited

 

Formula*

g/L
Enzymatic digest of casein 10.0
Meat extract 5.0
Yeast extract 1.0
Sodium pyruvate 10.0
L-glycine 12.0
Lithium chloride 5.0
Agar 20.0
Total 63.0
*Adjusted/supplemented as required to meet performance requirements

Preparation

Suspend 63g of the medium in one litre of deionised / purified water. Allow the medium to soak whilst mixing for 10 minutes. Heat with frequent agitation and boil for one minute to completely dissolve the medium. Sterilise at 121°C for 15 minutes. Cool to 45-50°C, add 50 ml egg yolk tellurite (BM0530), mix well and aseptically dispense into appropriate sterile containers.