Thermo Scientific™ Oxoid™ Pre-supplemented Dichloran Rose-Bengal Chloramphenicol (DRBC) (ISO) Agar Base (Dehydrated)

The Pre-Supplemented DRBC (ISO) Agar Base is a dehydrated medium designed for the isolation and enumeration of viable yeasts and molds associated with food spoilage. The formulation complies with ISO 21527-1: 2008, ensuring accurate results for food microbiology testing. Its pre-supplemented design eliminates the need for additional handling of chloramphenicol, enhancing convenience and laboratory safety.

Key Features and Benefits

1. Compliance with ISO Standards:
   • Fully adheres to ISO 21527-1: 2008, ensuring international standardization in microbiological testing of food products with water activity above 0.95 aW.
2. Pre-Supplemented Formulation:
   • Incorporates 0.1 g/L chloramphenicol directly in the agar base, removing the need for manual supplementation and reducing the risk of handling hazardous chemicals.
3. Selective Properties:
   • Inhibits bacterial growth while allowing yeasts and molds to thrive, ensuring clear colony visualization and enumeration.
4. Optimized Medium Composition:
   • Dichloran: Restricts the growth of spreading molds and controls colony size for improved detection.
   • Rose-Bengal: Enhances fungal colony differentiation and inhibits certain yeast growth at lower pH.
5. Enhanced Laboratory Safety:
   • Pre-supplementation minimizes chemical exposure and handling risks.

Specifications

Applications

1. Food Microbiology Testing:
   • Isolation and enumeration of viable yeasts and molds in food products with water activity above 0.95 aW, including high-moisture foods like fruits, dairy, and meat.
2. Quality Control:
   • Ensures accurate and reliable detection of spoilage organisms to maintain food quality and safety.
3. Research and Industry Use:
   • Suitable for studies on fungal contamination and spoilage in food products.

Preparation and Protocol

1. Preparation of Medium

1. Suspend 31.6 g of the dehydrated medium in 1 liter of distilled water.
2. Heat with frequent agitation until fully dissolved.
3. Autoclave at 121°C for 15 minutes to sterilize.

2. Plating Procedure

1. Allow the medium to cool to 45–50°C and pour into sterile Petri dishes.
2. Allow plates to solidify at room temperature.

3. Inoculation

1. Spread a sample or its dilution evenly across the agar surface.
2. Incubate plates at 25–30°C for 2–7 days, depending on the target organism.

4. Enumeration

1. Observe plates for fungal colonies.
2. Count and record colony-forming units (CFU) to determine the microbial load.

Composition

Advantages

1. Time and Labor Savings:
   • Pre-supplemented formulation reduces preparation time and eliminates additional steps.
2. Enhanced Accuracy:
   • Optimized composition ensures clear fungal colony isolation and size restriction for accurate enumeration.
3. Safety:
   • Pre-included chloramphenicol minimizes exposure to hazardous chemicals in the lab.
4. Wide Range of Applications:
   • Suitable for both food industry testing and research laboratories.

Comparison with Other Media

Standards Compliance

• ISO 21527-1: 2008: Microbiology of food and animal feeding stuffs - Enumeration of yeasts and molds.

References

1. BS ISO 21527-2: 2008. Microbiology of food and animal feeding stuffs - Enumeration of yeasts and molds.
2. Thermo Scientific product specifications.

This product is ideal for laboratories focused on food safety and spoilage analysis, offering a reliable, standardized, and user-friendly solution for fungal detection and enumeration.