Thermo Scientific™ Oxoid™ Demi-Fraser Broth (without Ferric Ammonium Citrate) (Dehydrated)

The Thermo Scientific™ Oxoid™ Demi-Fraser Broth (Dehydrated) is a selective secondary enrichment medium specifically designed for the isolation of Listeria spp., including Listeria monocytogenes, from food and environmental samples. This modified version of Fraser Broth contains reduced concentrations of selective agents (nalidixic acid and acriflavin hydrochloride) to aid the recovery of stressed cells. The removal of ferric ammonium citrate makes it compatible with subculture to imaging instrumentation and PCR-based assays.

Key Features

1. Selective Enrichment:
   • Supports the recovery of stressed Listeria cells from food and environmental samples.
2. PCR and Imaging Compatibility:
   • The absence of ferric ammonium citrate ensures compatibility with subculture to imaging systems and molecular assays, such as PCR-based methods.
3. Optimized for Secondary Enrichment:
   • Contains reduced levels of selective agents for enhanced recovery while maintaining selectivity.
4. Reliable Listeria Detection:
   • Effective for identifying Listeria monocytogenes, the most common pathogenic Listeria spp.
5. Versatile Application:
   • Suitable for use in food safety, environmental monitoring, and compliance testing workflows.

Applications

1. Food Microbiology

• Detection and recovery of Listeria spp. from processed and raw foods, including:
  • Dairy products
  • Meat and poultry
  • Seafood
  • Ready-to-eat foods

2. Environmental Monitoring

• Recovery of Listeria spp. from environmental swabs and samples in food production and processing facilities.

3. Molecular Assays

• Prepares samples for subculture into PCR-based assays or imaging instrumentation, facilitating modern diagnostic workflows.

Specifications

Preparation Instructions

1. Suspend: Suspend 57.5g of Demi-Fraser Broth powder in 1 liter of distilled water.
2. Mix and Heat: Heat gently while stirring to dissolve completely.
3. Sterilize: Autoclave at 121°C for 15 minutes.
4. Cool and Use: Allow to cool before inoculating with the sample.

Advantages

1. Enhanced Recovery: Optimized for recovering stressed Listeria cells.
2. Molecular Compatibility: Enables direct subculture into PCR assays and imaging systems without interference.
3. Reduced Selective Agents: Minimizes stress on target organisms while maintaining selectivity.
4. Wide Utility: Applicable across food, environmental, and diagnostic microbiology workflows.
5. Cost-Effective: High yield (8.7L per 500g) ensures economical testing for high-volume laboratories.

Storage and Stability

• Storage: Store the dehydrated medium at 10–30°C in a dry environment.
• Shelf Life: Refer to the product label for expiration date.

Packaging

• Product: Demi-Fraser Broth (without Ferric Ammonium Citrate) (Dehydrated)
• Catalog Numbers:
  • CM1053B: 500g
  • CM1053R: 2.5kg
• Yield: 8.7L of prepared medium per 500g

The Thermo Scientific™ Oxoid™ Demi-Fraser Broth (without Ferric Ammonium Citrate) is a versatile and reliable secondary enrichment medium for the isolation of Listeria spp. Its compatibility with modern diagnostic systems, enhanced recovery of stressed cells, and suitability for food and environmental testing workflows make it an indispensable tool for microbiology laboratories focused on food safety and quality assurance.