Dichloran Rose Bengal Chloramphenicol Agar

Dichloran Rose Bengal Chloramphenicol (DRBC) agar is based on the formulation described by King et al. and is used for the selective isolation and enumeration of yeasts and moulds from food samples.

The peptone provides the required carbon, nitrogen and vitamins. Glucose is a fermentable carbohydrate. Potassium di-hydrogen phosphate is a buffering agent and magnesium sulfate is a source of divalent ions and sulfate.

In order to curtail the size of the colony diameters of spreading fungi, the antifungal agent dichloran is added to the base and the pH is reduced to 5.6.

Rose Bengal suppresses growth of bacteria and restricts the size and height of colonies of more rapidly growing molds. The inclusion of chloramphenicol ensures the suppression of bacteria present in environmental and food samples.

Rose Bengal is absorbed by yeast and mold colonies and this further aids in their enumeration.

Occasionally reduced recovery of yeasts may be encountered due to the increased activity of Rose Bengal at pH 5.6.

Used for the selective isolation and enumeration of yeasts and moulds from food samples.

Additional Information

Shelf Life (days): 1095 days

Storage Temp (C): 10-30°C

Dehydrated Medium Appearance: Fine Powder

Prepared Medium Appearance: Firm Gel

Dehydrated Medium Colour: Pink Beige

Prepared Medium Colour: Pink

Dehydrated PH: 5.6 0.2

Prepared PH: 5.6 0.2

Recommended Incubation: Incubate yeast at 25±1°C for 48 hours and moulds at 25±1°C for 3-10 days

Formula*g/L

Peptone: 5.0

Glucose: 10.0

Potassium di-hydrogen phosphate: 1.0

Magnesium sulphate: 0.5

Dichloran: 0.002

Rose Bengal: 0.025

Agar: 15.0

Chloramphenicol: 0.1

Total: 31.6

*Adjusted/supplemented as required to meet performance requirements