(AB) Listeria Enrichment Broth, 2 Kilograms

Listeria Enrichment Broth was developed by Loveft for the recovery of Listeria from milk. Samples were first incubated in the enrichment broth at 30°C for 24 to 48 hours prior to streaking on McBride Agar. Peptones and yeast extracts supply necessary growth nutrients. The phosphate salts supply buffering capacity. The broth is made selective by the addition of antibiotics. Cycloheximide inhibits saprophytic fungi. Nalidixic acid inhibits the growth of Gram negative microorganisms and acriflavine inhibits Gram positive microorganisms. Listeria Enrichment Broth is used for the selective enrichment of Listeria monocytogenes. (Alpha Biosciences # L12-110-2Kg)

Use: Listeria Enrichment Broth is used for the selective enrichment of Listeria monocytogenes.

Description: Listeria Enrichment Broth was developed by Loveft for the recovery of Listeria from milk. Samples were first incubated in the enrichment broth at 30°C for 24 to 48 hours prior to streaking on McBride Agar. Peptones and yeast extracts supply necessary growth nutrients. The phosphate salts supply buffering capacity. The broth is made selective by the addition of antibiotics. Cycloheximide inhibits saprophytic fungi. Nalidixic acid inhibits the growth of Gram negative microorganisms and acriflavine inhibits Gram positive microorganisms.

Formula* per Liter:

• Casein Digest Peptone ......... 17.0g
• Pancreatic Digest of Soybean Meal.... 3.0g
• Dextrose .................................... 2.5g
• Sodium Chloride .................................... 5.0g
• Yeast Extract ............................. 6.0g
• Disodium Phosphate ............................ 2.5g
• Cyclohexamide ......................... 0.5g
• Acriflavine ........................................... 0.015g
• Naldixic Acid........................... 0.04g

Final pH: 7.3 ± 0.2 at 25.0°C

* Grams per liter may be adj. or formula supplemented to obtain desired performance

Preparation: Mix 36.1 grams of medium a Liter of purified water. Heat with repeated stirring to dissolve completely. Dispense and sterilize by autoclaving at 121.0°C for 15 minutes

Quality Control Specifications:

1. The powder is homogeneous, free flowing and light beige.
2. Visually the prepared base is orange amber with greenish opalescent top.
3. Expected cultural response after 24-48 hours at 35.0°C.

Organism                                                                           Result

Escherichia coli ATCC 25922                                           Inhibited

Listeria monocytogenes ATCC 7644                                 Growth

Listeria monocytogenes ATCC 15313                               Growth

Staphylococcus aurous ATCC 25923                               Inhibited

Sacromyces cerevisiae ATCC 9763                                 Inhibited

Storage: Store the sealed bottle containing the dehydrated medium at 2 to 8.0°C. Once opened and recapped, place the container in a low humidity environment at the same storage temperature. Protect it from moisture and light. The dehydrated medium should be discarded if it is not free flowing or if the color has changed from the original light beige color.