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Lauryl Tryptose Broth

Lauryl Tryptose Broth is used for the detection of coliform bacteria in water and wastewater in a laboratory setting. Lauryl Tryptose Broth is not intended for use in the diagnosis of disease or other conditions in humans.

The coliform group of bacteria includes aerobic and facultative anaerobic, Gram-negative, non-sporeforming bacilli that ferment lactose and form acid and gas at 35°C within 48 hours. Members of the Enterobacteriaceae comprise the majority of this group, but organisms such as Aeromonas spp. may also be included. Procedures to detect and confirm coliforms are used in testing water, foods, dairy products, and other materials.

Lauryl Tryptose Broth, also referred to as Lauryl Sulfate Broth, is prepared according to the formula of Mallmann and Darby. Their investigation found that buffered tryptose lactose broth permitted "slow lactose fermenters" to increase gas production faster. Sodium Lauryl Sulfate produced the best results for inhibition of organisms other than coliforms. Lauryl Tryptose Broth, abbreviated as LTB, is used in the presumptive phase of the Standard Total Coliform Fermentation Technique in the examination of water, and coliform detection of foods.

 

Formula Liter
Tryptose 20 g
Lactose 5 g
Sodium Chloride 5 g
Monopotassium Phosphate 2.75 g
Disodium Phosphate 2.75 g
Sodium Lauryl Sulfate 0.1 g

Final pH: 6.8 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.

Directions

  1. Dissolve 35.6 g of the medium in one liter of purified water.
  2. Prepare double strength broth for evaluating 10 mL samples.
  3. Distribute into tubes containing inverted fermentation Durham tubes.
  4. Autoclave at 121°C for 15 minutes.

Order Details

Product # Product Description
7324A Lauryl Tryptose Broth, 500 g
7324T Lauryl Tryptose Broth, 5 kg