Acetate Differential Agar is formulated based on the observation that most Escherichia coli strains can utilize acetate as their only carbon source, whereas Shigella species are generally unable to do so. The medium contains Sodium Acetate as the carbon source and Bromothymol Blue as the pH indicator. When an organism metabolizes the acetate, it releases alkaline byproducts, raising the pH of the medium. This shift in pH causes the indicator to change from its original green color to blue. Inorganic ammonium salts in the medium provide the necessary nitrogen source for growth.
Advantages
- Specific Differentiation: Highly effective at distinguishing non-fermenting E. coli from Shigella, which is a critical step in enteric diagnostics.
- Clear Visual Interpretation: The distinct color change from green to deep blue provides an unambiguous positive result.
- Selective Metabolic Test: The chemically defined nature of the medium ensures that growth only occurs if the organism can process acetate.
- Standardized Results: Follows established biochemical testing protocols for the identification of members of the Enterobacteriaceae family.
- Reliable Quality: Produced by Condalab with high-purity ingredients to ensure consistent metabolic responses.
Technical specifications
| Catalogue number |
1192 |
| Brand |
Condalab |
| Application |
Differentiation of Shigella and Escherichia coli |
| Typical Composition (g/L) |
Sodium Acetate (2.0); Sodium Chloride (5.0); Magnesium Sulfate (0.2); Monoammonium Phosphate (1.0); Dipotassium Phosphate (1.0); Bromothymol Blue (0.08); Bacteriological Agar (20.0) |
| Final pH (at 25 °C) |
6.7 ± 0.2 |
| Preparation |
29.2 g/L |
| Storage Temperature |
2 – 25 °C |
Available packaging options
| 1192 |
500 g plastic bottle |
