Bile Esculin Agar A1 Quality – HX-MEDIA

Bile Esculin Agar – HX-MEDIA

Product Overview

Bile Esculin Agar is a selective and differential culture medium used for the isolation and identification of Group D streptococci and Enterococci, particularly Enterococcus faecalis. The medium contains bile salts, which inhibit most Gram-positive bacteria other than enterococci, making it selective.

It also contains esculin and ferric citrate. Organisms capable of hydrolyzing esculin produce esculetin, which reacts with ferric ions to form a dark brown to black complex, resulting in characteristic blackening of the medium.

Bile Esculin Agar is widely used in clinical diagnostics, water testing, and food microbiology laboratories for the presumptive identification of enterococci and differentiation from other streptococci. It provides clear visual results, high selectivity, and reliable performance, making it essential for routine microbiological analysis.

🔬 Key Features

• Selective for enterococci and Group D streptococci

• Differential through esculin hydrolysis and blackening. Clear, easy-to-read reaction

• Reliable for confirming bile-tolerant, esculin-positive organisms

• Bile Esculin Agar Fits clinical, food, water, and environmental testing workflows

🎯 Applications

• Isolation and identification of Enterococcus spp.

• Differentiation of Group D streptococci from other streptococci

• Confirmation of enterococcal presence in clinical, food, water, and environmental samples

• Selective plating following enrichment procedures

🧪 Composition (Typical)

• Peptone (6 g) – nutrient source

• Bile Salts (20 g) – selective inhibitor

• Esculin (1 g) – differential substrate

• Ferric Ammonium Citrate (0.5 g) – blackening indicator

• Agar (15 g) – solidifying agent

• Distilled Water (1 L)

• Final pH: 6.6 ± 0.2

🛠️ How to Use

• Streak specimen or inoculate plate using standard aseptic technique.

• Incubate at 35–37 °C for 18–24 hours.

• Positive reaction: brown to black coloration in the medium around colonies.

• Negative reaction: no darkening; medium remains unchanged.

👍 Ideal For

✔ Identifying Enterococcus spp.

✔ Differentiating Group D streptococci

✔ Isolating bile-tolerant, esculin-positive bacteria

✔ Screening food, water, and clinical samples

✔ Teaching labs (clear blackening reaction)