Harlequin® Tryptone Bile Glucuronide Agar (TBX) is used for the enumeration of E. coli in food and animal feed and is not intended for use in the diagnosis of disease or other conditions in humans.
Tryptone Bile Glucuronide Agar is recommended by ISO 16649-1:2001, ISO 16649-2:2001 and ISO 16649-3:2015 for enumeration of β-glucuronidase positive Escherichia coli in products intended for human consumption or for the feeding of animals. The medium contains tryptone as a source of nitrogen and amino acids, bile salts act as a selective against Gram-positive organisms and agar is the gelling agent. 5-bromo-4-chloro-3-indolyl-β-D-glucuronide (X-glucuronide) is a chromogen for the detection of the β-D-glucuronidase enzyme which is present in most E. coli* but not other coliforms. The intracellular enzyme present in E. coli is able to break the bond between the substrate and the chromophore which dimerizes is the presence of oxygen to form an insoluble colored compound within the cell. The accumulation of the colored chromophore results in blue colonies on the agar.
*96-97% of E.coli are β-D-glucuronidase positive. A notable exception is E. coli O157:H7
| Formula | Liter |
| Enzymatic Digest of Casein | 20.0 g/L |
| Bile Salts No. 3 | 1.5 g/L |
| X-glucuronide | 0.075 g/L |
| Agar | 15.0 g/L |
Final pH: 7.2 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.
Preparation
- Suspend 36.5 grams of the medium in 1 liter of purified water.
- Heat with frequent agitation and boil for one minute to completely dissolve the medium.
- Autoclave at 121°C for 15 minutes.
- Cool to 45-50°C.
Product was previously known as Acumedia Product: 7692 Harlequin Tryptone Bile Glucuronide Agar (TBX); and LabM Product: HAL003 Harlequin™ TBGA/TBX (Tryptone Bile Glucuronide Agar)
Order Details
| Product # | Product Description |
| NCM1001A | Harlequin Tryptone Bile Glucuronide Agar (TBX), 500 g |
| NCM1001B | Harlequin Tryptone Bile Glucuronide Agar (TBX), 5 kg |
| NCM1001C | Harlequin Tryptone Bile Glucuronide Agar (TBX), 10 kg |
| NCM1001D | Harlequin Tryptone Bile Glucuronide Agar (TBX), 25 kg (European only size) |
| NCM1001E | Harlequin Tryptone Bile Glucuronide Agar (TBX), 50 kg (US only size) |
Reference Material
NCM1001 - Harlequin Tryptone Bile Glucuronide Agar (TBX), Safety Data Sheet [Danish] [Dutch] [English] [EU English] [Finnish] [French] [German] [Italian] [Spanish, Mexico] [Swedish]
NCM1001 - Harlequin Tryptone Bile Glucuronide Agar (TBX), Technical Specifications Sheet [English]
For additional information or questions about product SDS documents, please contact Neogen at SDS@neogen.com.