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Thermo Scientific™ OF King Medium w/1% Dextrose, Lactose, Maltose, Mannitol, Sucrose, Xylose

Catalog No. R061903
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Media Type:
OF King Medium
OF King Medium Base Control
Includes:
1% Maltose
Base Control
This item is not returnable. View return policy
This item is not returnable. View return policy

Use OF King Medium to determine oxidative and fermentative metabolism of carbohydrates by gram-negative bacilli.

Determine oxidative and fermentative metabolism of carbohydrates by gram-negative bacilli using Thermo Scientific™ Remel™ OF King Medium. Hugh and Leifson first reported that microorganisms which utilize carbohydrates oxidatively produce only a minimal amount of acid1. Oxidative-Fermentative (OF) Medium was developed with a ratio of peptone to carbohydrate that minimized the formation of alkaline by-products and enhanced acid production by oxidative organisms. OF Medium is especially suitable for determining the carbohydrate metabolic pathway of gram-negative bacilli2.

Typical fermentation media contain approximately 2% peptone and 1% carbohydrate. In media containing high concentrations of peptones, oxidative microorganisms produce alkaline by-products in quantities that neutralize the acid produced from carbohydrate metabolism.

OF Medium is a semisolid medium with a low peptone to carbohydrate ratio that contains the pH indicator bromthymol blue. Organisms which metabolize carbohydrate in OF medium produce acid in quantities sufficient to prevent its neutralization by alkaline peptone by-products.

  • Ready to use - Convenience of prepared media
  • Easy to interpret - Color change from green to yellow indicates positive test for acid production.
    When testing for motility, growth diffused away from stab line of inoculation indicates a positive test whereas growth confined to stab line indicates negative test.
    Acid production in the open tube (without mineral oil overlay) indicates oxidative metabolism whereas acid production in both (with and without mineral oil overlay) tubes indicates fermentative metabolism

OF Base Medium contains casein peptone as the substrate and bromthymol blue as the pH indicator. Dipotassium phosphate promotes fermentation and also serves as a buffer. Agar allows for detection of motility and aids in even distribution of acid produced at the surface of the medium.

Different carbohydrates such as dextrose, lactose, maltose, mannitol, sucrose, and xylose (available separately) can be added to the base medium to study carbohydrate utilization.

In the presence of acid, bromthymol blue indicator changes from green to yellow.

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Remel™ and Oxoid™ products are now part of the Thermo Scientific brand.

TRUSTED_SUSTAINABILITY

Specifications

Format 15mm x 103mm Tube
Media Type OF King Medium Base Control
Product Type Microbiology Media
Includes Base Control
Quantity 20 x 5 mL
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