Dichloran Glycerol Agar (DG18), 90mm Plate

Description

7563 – Dichloran Glycerol Agar (DG18), 90mm Plate is a ready-to-use prepared plate supplied by SGL for routine microbiological testing. It is suitable for use in food and beverage; contract testing laboratories and environmental testing. Manufactured and quality controlled to SGL internal specifications.

Laboratories use Dichloran Glycerol Agar (DG18) to selectively isolate and enumerate osmophilic yeasts and xerophilic moulds in dried and semi-dried foods with a water activity (aᵥ) of 0.95 or below. The medium supports enumeration methods described in ISO 21527-2 and applicable performance-testing requirements of ISO 11133. For foods with a water activity above 0.95, laboratories generally use Dichloran Rose Bengal Chloramphenicol (DRBC) Agar. Water activity means the water available for microbial growth, rather than total moisture content.

The formulation contains 18% glycerol, which lowers the medium’s water activity to approximately 0.95. This reduced water activity supports the recovery of fungi adapted to dry or high-solute environments and helps limit competition from organisms that require higher water activity.

Peptones supply carbon, nitrogen, vitamins and minerals, while glucose provides a carbohydrate source for energy. Magnesium sulphate supplies magnesium and sulphur to support fungal growth and sporulation. Dichloran restricts the spread of mucoraceous fungi and limits colony size, making colonies easier to distinguish and count. Chloramphenicol inhibits the growth of bacteria that may occur in the sample. Agar solidifies the medium and provides a stable surface for colony development and enumeration.

This medium is the preferred medium to the recovery of Wallemia sebi (mellicola) as DRBC isn’t able to recover that organism.

SGL manufactures and quality-controls the product to its internal specifications and in compliance with ISO 9001 (reference FM37824). A UKAS-accredited laboratory operating to ISO/IEC 17025 (accreditation number 4356) tests the product. At the customer’s request, the laboratory can also perform additional specification testing.

SKU: 7563