Bile Esculin Agar is recommended for isolation and presumptive identification of group D Streptococci from food and pharmaceutical products. Enterococci and Group D Streptococci hydrolyse esculin to esculetin and dextrose, which reacts with ferric citrate producing brownish black precipitate. Identification of enterococci and differentiation of Group D strptococci from non Group D can thus be performed using this agar medium.
- Appearance: Light yellow to brownish yellow homogeneous free flowing powder
- Gelling: Firm, comparable with 1.5% Agar gel
- Color and Clarity of prepared medium: Amber colored, clear to slightly opalescent gel with a bluish tinge forms in Petri plates or in tubes as slants
- Reaction of 6.5% w/v aqueous solution at 25°C. pH : 6.6±0.2
- Cultural characteristics observed in an increased atmosphere of Carbon dioxide after an incubation at 35-37°C for 18-24 hours