Liofilchem™ Bacillus cereus Agar Base (Mossel)

The Liofilchem™ Bacillus cereus Agar Base (Mossel) is a basal medium specifically designed for the isolation, enumeration, and identification of Bacillus cereus in food and other materials. When supplemented with Polymyxin B and Egg Yolk Emulsion, this medium becomes Mannitol-Egg Yolk-Polymyxin (MYP) Agar, adhering to ISO 7932, ISO 21871, and FDA-BAM standards. It is effective in detecting low numbers of B. cereus in the presence of other contaminants.

Key Features

1. Highly Selective:
   • Detects Bacillus cereus even in samples with high background flora using Polymyxin B for selectivity.
2. Differentiation of B. cereus:
   • Identifies B. cereus based on:
     • Mannitol-negative fermentation (pink colonies).
     • Lecithinase activity (precipitation halo around colonies).
3. Standards Compliant:
   • Meets ISO and FDA-BAM guidelines, ensuring reliability and reproducibility.
4. Nutrient-Rich:
   • Contains enzymatic digest of casein and beef extract for optimal bacterial growth.

Typical Formula (g/L)

Applications

1. Food Microbiology:
   • Detects Bacillus cereus in raw, processed, and ready-to-eat foods.
2. Clinical Microbiology:
   • Identifies Bacillus cereus in stool samples.
3. Environmental Testing:
   • Monitors contamination in food production environments.

Preparation Instructions

1. Suspend 45g of Bacillus cereus Agar Base powder in 950 mL of distilled water.
2. Heat to boiling while stirring until fully dissolved.
3. Autoclave at 121°C for 15 minutes.
4. Cool the medium to 45-50°C, then aseptically add:
   • Rehydrated Bacillus cereus Supplement (2 vials, 10 mL total).
   • 50 mL of Egg Yolk Emulsion (Ref. 80219).
5. Mix thoroughly and pour into sterile Petri dishes.

Technique and Results Interpretation

1. Inoculate the medium using the spread plate method.
2. Incubate at 30 ± 1°C for 24 hours under aerobic conditions.
3. Results:
   • Bacillus cereus: Pink colonies (mannitol-negative) with a lecithin precipitation halo.
   • Non-B. cereus bacteria:
     • Bacillus subtilis: Yellow colonies (mannitol-positive) without precipitation halo.
     • Escherichia coli: Growth inhibited.

Storage and Shelf Life

• Storage:
  • Dehydrated medium: 10-30°C in original packaging.
  • Prepared plates: 2-8°C, protected from light.
• Shelf Life:
  • Dehydrated medium: 4 years.

Quality Control

Warnings and Precautions

1. For professional use only.
2. Follow aseptic techniques and standard laboratory safety protocols.
3. Consult the Safety Data Sheet (SDS) for proper handling and disposal.

Advantages

• Selective and Sensitive:
  • Enables detection of low numbers of B. cereus in complex samples.
• Standards Compliant:
  • Conforms to ISO and FDA-BAM for food and clinical microbiology testing.
• Accurate Differentiation:
  • Provides clear results with distinct colony morphology for B. cereus.
• Versatile:
  • Suitable for food, clinical, and environmental microbiology applications.

Packaging

References

1. ISO 7932:2004 - Enumeration of presumptive Bacillus cereus using colony count technique.
2. ISO 21871:2006 - Detection of low numbers of presumptive Bacillus cereus.
3. FDA-BAM Chapter 14 (2012) - Bacillus cereus.
4. Mossel, D.A.A., et al. (1967). Enumeration of Bacillus cereus in foods. Appl. Microbiol. 15: 650-653.
5. Donovan, K.O. (1958). A selective medium for Bacillus cereus in milk. J. Appl. Bacteriol. 21: 100-103.

Why Choose Liofilchem Bacillus cereus Agar Base (Mossel)?

• Trusted by laboratories for reliable Bacillus cereus detection and enumeration.
• Backed by international standards for food microbiology testing.
• Provides accurate differentiation of Bacillus cereus from other contaminants.