King′s B Agar

King′s B Agar is a specialized microbiological medium designed to enhance the production of fluorescein while inhibiting the formation of pyocyanin. The medium contains mixed peptones that provide essential nitrogenous nutrients, carbon, sulfur, and trace elements. Glycerol serves as a carbon source, while dipotassium hydrogen phosphate acts as a buffering agent. Magnesium sulfate is included to activate fluorescein production. When used for culturing Pseudomonas aeruginosa, the colonies are surrounded by a yellow to greenish-yellow zone due to fluorescein production, which fluoresces under UV light. If pyocyanin is also synthesized, a bright green color is observed. The medium is particularly useful for differentiating Pseudomonas aeruginosa from other species like Pseudomonas fluorescens and Pseudomonas putida, as the latter do not fluoresce under UV light and grow poorly on MacConkey Agar.

King Agar B is suitable for the detection and enumeration of fluorescing bacteria in water, particularly Pseudomonas fluorescens in drinking water. The media is also useful for distinguishing Pseudomonas aeruginosa from other Pseudomonas species based on pigment production and fluorescence under UV light.

NutriSelect^® Basic is a powdered culture media offering

• Quality control with growth promotion test according to industry standards
• Quality assurance acc. to ISO 9001
• Cost-efficient powdered media

Dissolve 33 g in 990 ml distilled water and add 10 ml glycerol (Cat. No. 49769). Sterilize by autoclaving at 121°C for 15 minutes.
Optional CFC Selective Supplement (Cat. No. 53477) can be added to make the media selective.

Multidish application

We offer two media types: the superior granulated GranuCult^® and the cost-efficient powdered NutriSelect^® culture media, depending on your needs.
The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.

GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany

NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany

This product will be discontinued in the near future; however, stock is still available. The recommended replacement product is 1.10991 - KING agar B (base) (Dansk Standard)