Thermo Scientific™ Tryptone Bile X-Glucuronide (TBX) Medium (Dehydrated)

Description

• Detect and enumerate Escherichia coli in food and animal feed samples with Thermo Scientific™ Oxoid™ Typtone Bile X-Glucuronide (TBX) Medium (Dehydrated)
• The medium meets the formulation and performance criterion laid down in ISO 16649 1, 2, 3 and ISO 11133:2014 4
• TBX Medium builds on the speed, reliability and recovery from frozen samples and detection of poor lactose fermenters offered by the original Tryptone Bile Agar 4,5 , with the addition of a chromogenic agent, X-glucuronide, which detects glucuronidase activity, an enzyme shown to be highly specific for Escherichia coli 6
• Use TBX Medium for selective detection and enumeration of Escherichia coli in food and animal feed samples
• Selective: presence of bile salts in the medium provide selectivity against Gram-positive bacteria, particularly bacilli and fecal streptococci
• Easy-to-read: due to the addition of chromogenic 5-bromo-4-chloro-3-indolyl-beta-D-glucuronide (X-glucuronide), E
• coli appear as blue/green colonies
• ISO compliant: meets the formulation and performance criteria laid down in ISO 16649 and ISO 11133:2014
• Most Escherichia coli strains can be differentiated from other coliforms by the presence of the enzyme glucuronidase
• However, approximately 3 to 4% of Escherichia coli are glucuronidase negative, notably Escherichia coli O157 strains 7
• The chromogen in TBX Medium is 5-bromo-4-chloro-3-indolyl-beta-D-glucuronide (X-glucuronide) and is targeted by glucuronidase
• Escherichia coli cells are able to absorb this complex intact and intracellular glucuronidase splits the bond between the chromophore and the glucuronide
• The released chromophore is colored and builds up within the cells, causing Escherichia coli colonies to be colored blue/green
• Not all products are available for sale in all territories
• Please inquire
• Remel™ and Oxoid™ products are now part of the Thermo Scientific brand.