BAIRD PARKER AGAR BASE (VEG.)

Veg Baird Parker Agar Base is prepared by using vegetable peptones which are free from BSE/TSE risks. This medium is modification of medium developed by Baird Parker from the tellurite – glycine formulation of Zebovitz et al for isolation of Staphylococcus aureus from foods. Proteolytic bacteria produce a clear zone around colony in egg yolk containing media. A clear zone and grey-black colonies on this medium are diagnostic for coagulase positive Staphylococci. Upon further incubation, an opaque zone is developed around colonies, which can be due to lipolytic activity. This medium, like the conventional medium is found to be less inhibitory to Staphylococcus aureus than other media, at the same time being more selective.
However, identity of Staphylococcus aureus isolated on Baird-Parker Veg Agar must be confirmed with a coagulase reaction. Baird-Parker Veg Agar Base can also be used to detect coagulase activity by adding Fibrinogen Plasma Trypsin Inhibitor Supplement dissolved in 10 ml sterile distilled water added to 90 ml sterile molten medium kept at 45-50?C. Mix well and pour into plates. On this medium coagulase positive Staphylococcal colonies are white to grey-black surrounded by an opaque zone of coagulase activity within 24-40 hours of incubation at 35?C. Reduction in tellurite is necessary because of absence of egg yolk emulsion. This results in translucent agar and white to grey coloured colonies of Staphylococci. For quantitative results select 20 – 200 colonies. Count Staphylococcus aureus like colonies and test them for coagulase reaction. Report Staphylococcus aureus per gram of food.

for isolation and enumeration of coagulase positive Staphylococci from food and other products