Fraser Broth Base
PRODUCT INFORMATION

DESCRIPTION: Fraser Broth Base was first described by Fraser and Sperber¹ and is used for the rapid detection of Listeria from food and environmental samples. Peptones and yeast extracts supply necessary growth nutrients. The phosphate salts supply buffering capacity. The addition of esculin and ferric ammonium citrate detect esculin hydrolyzing bacteria (Listeria). The broth is made selective by the addition of antibiotics and other agents. Lithium chloride inhibits Enterococcus sp. which also hydrolyze esculin. Nalidixic acid inhibits the growth of gram-negative microorganisms and acriflavine inhibits gram-positive microorganisms.

Formula* per Liter

  Pancreatic Digest of Casein........................................ 5.0g

  Peptic Digest of Animal Tissue................................... 5.0g

  Beef Extract................................................................... 5.0g

  Yeast Extract................................................................. 5.0g

  Sodium Chloride.......................................................... 20.0g

  Disodium Phosphate................................................... 9.6g

  Monopotassium Phosphate........................................ 1.35g

  Esculin.......................................................................... 1.0g

  Acriflavine………………………………………………….0.024g

  Nalidixic Acid………………………………………………0.020g

  Lithium Chloride........................................................... 3.0g

Fraser Broth Supplement:

      Per 10 mL Vial

       Ferric Ammonium Citrate....................... 0.5 g

*Adjusted and/or supplemented as required to meet performance criteria.

Final pH: 7.2 ± 0.2 at 25ºC