Thermo Scientific™ Oxoid™ Chloramphenicol Selective Supplement

The Oxoid™ Chloramphenicol Selective Supplement is a freeze-dried additive designed to enhance the selectivity of culture media for the isolation and enumeration of yeasts and molds from various sample types, including food and clinical specimens. Its broad applicability in specialized media makes it a versatile tool in both clinical mycology and food microbiology.

Specifications

Applications

1. Isolation of Yeasts and Molds Associated with Spoilage:
   • Add the Chloramphenicol Selective Supplement to DRBC Agar Base (Part No. CM0727B) to inhibit bacterial growth and support the isolation of spoilage-associated fungi and yeasts.
2. Enumeration of Yeasts and Molds in Food Samples:
   • Add the supplement to Rose Bengal Chloramphenicol Agar Base (Part No. CM0549B) for accurate enumeration of fungi and yeasts in food products.
3. Clinical Mycology:
   • Use in Sabouraud Dextrose Medium for isolating dermatophytes, other fungi, and yeasts from clinical samples (e.g., skin, hair, nails, genital, respiratory, and urine samples) of immunocompromised patients.
4. Other Media Applications:
   • Dichloran Glycerol (DG18) Medium: For enumeration of xerophilic molds in foods.
   • Brain Heart Infusion Medium (with Chloramphenicol and Cycloheximide): For selective fungal isolation.
   • AFPA Medium: For isolation of Aspergillus flavus and Aspergillus parasiticus in food testing.
   • OGYE Medium (Oxytetracycline Glucose Yeast Extract): For yeast and mold detection in food samples.

Key Features

1. Selective Inhibition:
   • Chloramphenicol effectively suppresses bacterial growth, enhancing the selectivity of the medium for fungi and yeasts.
2. Versatile Usage:
   • Applicable in a wide range of selective media used for clinical, food, and environmental microbiology.
3. Ease of Preparation:
   • Freeze-dried formulation ensures long shelf life and straightforward reconstitution.
4. High Yield:
   • One vial prepares 2 liters of medium, ensuring efficient resource utilization.

Preparation and Protocol

1. Reconstitution

1. Aseptically reconstitute the freeze-dried supplement with sterile distilled water according to the manufacturer's instructions.
2. Mix thoroughly to ensure complete dissolution.

2. Incorporation into Media

1. Prepare the base medium (e.g., DRBC Agar Base, Rose Bengal Chloramphenicol Agar Base).
2. Cool the autoclaved medium to 45–50°C.
3. Aseptically add the reconstituted Chloramphenicol Selective Supplement to the cooled medium.
4. Mix gently but thoroughly to ensure even distribution.

3. Plating and Incubation

1. Pour the medium into sterile Petri dishes.
2. Allow the plates to solidify at room temperature.
3. Inoculate with the test sample and incubate under appropriate conditions:
   • Temperature: 25–30°C
   • Duration: 2–7 days

Use Cases

• Food Microbiology:
  • Detection of spoilage yeasts and molds in dairy, bakery, and beverage products.
• Clinical Mycology:
  • Identification of dermatophytes and opportunistic fungi in immunocompromised patients.
• Environmental Testing:
  • Monitoring fungal contamination in industrial and environmental settings.

Comparison with Other Supplements

Advantages

1. High Selectivity: Effectively inhibits bacterial contaminants, allowing for the clear detection of fungal colonies.
2. Wide Compatibility: Suitable for multiple media types, enhancing its utility in diverse applications.
3. Ease of Handling: Freeze-dried format ensures long-term stability and easy storage.
4. Standardized Formulation: Delivers consistent results across different laboratories and testing conditions.

This product is an essential component for laboratories focused on food safety, clinical diagnostics, and environmental monitoring, ensuring accurate and reliable results in fungal detection and enumeration.