This medium is the liquid version of the Bile Esculin Azide Agar. It contains a Peptone Mixture and Yeast Extract as the primary sources of nitrogen, amino acids, and essential B-vitamins. The selectivity is provided by Ox Bile, which inhibits most Gram-positive bacteria, and Sodium Azide, which suppresses Gram-negative flora. The differential principle is based on the hydrolysis of Esculin. Enterococci break down esculin into esculetin, which then reacts with Ferric Ammonium Citrate. In this liquid format, a positive result is indicated by the medium turning dark brown or black, signaling the presence of organisms capable of esculin hydrolysis under selective pressure.
Advantages
- High Selectivity: The synergistic effect of Sodium Azide and Ox Bile ensures that only resistant Enterococci proliferate, minimizing false positives from other Streptococci.
- Rapid Enrichment: The liquid format allows for the efficient recovery and expansion of Enterococci populations from environmental samples.
- Clear Result Interpretation: The blackening of the broth provides a simple, high-contrast visual confirmation of the target organism's metabolic activity.
- Standardized Testing: Widely used in water microbiology as part of the multiple-tube fermentation method or as a confirmatory enrichment step.
- Nutrient Balanced: Supports the growth of even stressed cells while maintaining strict selective conditions.
Technical specifications
| Catalogue number |
1359 |
| Brand |
Condalab |
| Application |
Selective enrichment and presumptive identification of Enterococci |
| Typical Composition (g/L) |
Peptone Mixture (20.0); Yeast Extract (5.0); Ox Bile (10.0); Sodium Chloride (5.0); Esculin (1.0); Ferric Ammonium Citrate (0.5); Sodium Azide (0.15) |
| Final pH (at 25 °C) |
7.1 ± 0.2 |
| Preparation |
41.65 g/L |
| Storage Temperature |
2 – 25 °C |
Available packaging options
| 1359 |
500 g plastic bottle |
