0120216

Half Fraser Broth in Bags

For enrichment of samples for Listeria sp. and Listeria monocytogenes in accordance with ISO 11290, suitable for microbiology

• Synonym(s): Fraser broth primary enrichment
• UNSPSC Code: 41106200
• NACRES: NA.74

Properties

• agency: ISO 11290; according to ISO 11290
• Quality Level: 200
• sterility: sterile
• form: liquid
• shelf life: limited shelf life, expiry date on the label
• feature: ready-to-use
• composition: acriflavin hydrochloride, 0.0125 g/L ; ammonium ferric citrate, 0.5 g/L ; casein peptone, 5 g/L ; di-sodium phosphate dihydrate, 12.0 g/L ; esculin, 1.0 g/L ; lithium chloride, 3.0 g/L ; meat extract, 5 g/L ; meat peptone, 5 g/L ; nalidixic acid, 0.010 g/L ; potassium dihydrogen phosphate, 1.35 g/L ; sodium chloride, 20 g/L ; yeast extract, 5 g/L
• technique(s): microbiological culture: suitable
• final pH: 7.2±0.2 (25 °C)
• application(s): agriculture; environmental; food and beverages; industrial qc; pathogen testing; sample preparation; microbiology
• suitability: Listeria spp.

Description

General description

Half Fraser broth is a selective enrichment medium designed to help the recovery of Listeria sp. This medium contains peptone, casein, yeast extract, and meat extract, which provide essential nutrients like carbon and nitrogenous compounds, including vitamins, amino acids, and trace ingredients. Phosphates buffer the medium while sodium chloride maintains osmotic equilibrium. Nalidixic acid and acriflavine inhibit the growth of Gram-negative and Gram-positive organisms respectively, except Listeria sp. Listeria sp. hydrolyze esculin to glucose and esculetin. The latter combines with ferric ions of ferric ammonium citrate, resulting in the formation of 6-7-Dihydroxycoumarin, a black-brown complex. Ferric ammonium citrate also enhances the growth of L. monocytogenes. The high salt tolerance (of sodium chloride) of Listeria is used as means to inhibit the growth of Enterococci. Lithium chloride is also used to inhibit Enterococci, which also possess the ability to hydrolyze esculin.

Application

Half Fraser broth is used for the selective pre-enrichment and detection of Listeria sp. in food and environmental specimens.

Safety Information

• Storage Class: 12 - Non Combustible Liquids
• wgk_germany: WGK 2
• flash_point_f: Not applicable
• flash_point_c: Not applicable