Thermo Scientific™ Bacillus cereus Selective Agar Base (Dehydrated)

Description

Selectively isolate and enumerate Bacillus cereus from food samples with Thermo Scientific™ Oxoid™ Bacillus cereus Selective Agar Base (Dehydrated). Bacillus cereus Selective Agar Base meets the requirements for a medium that is sufficiently selective to be able to detect small numbers of Bacillus cereus cells and spores in the presence of large numbers of other food contaminants. The medium is also sufficiently diagnostic that colonies of Bacillus cereus are readily identified and confirmed by microscopic examination.

Bacillus cereus is a Gram-positive, rod-shaped beta hemolytic bacterium commonly found in soil and food. The role of Bacillus cereus in food poisoning, particularly from the consumption of contaminated rice, is now well documented^1,2,3. The organism has also been implicated in eye infections^{4, 5} and a wide range of other conditions, including abscess formation, meningitis, septicemia and wound infection.

Bacillus cereus is recognized as a significant pathogen in post-operative and post-traumatic wounds of orthopedic patients⁶. Amongst veterinarians, Bacillus cereus is a known cause of disease, especially mastitis, in ewes and heifers⁷.

• Differential: differentiates cereus from other species of Bacillus based on their resistance to polymyxin, lack of mannitol fermentation, and the presence of lecithinase.
• Selective: inhibits the growth of gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa due to the addition of polymixin B supplement.

Bacillus cereus Selective Agar is based on the highly specific diagnostic and selective PEMBA medium, developed by Holbrook and Anderson¹ for the isolation and enumeration of Bacillus cereus in foods. It meets the requirements for a medium that is sufficiently selective to be able to detect small numbers of Bacillus cereus cells and spores in the presence of large numbers of other food contaminants. The medium is also sufficiently diagnostic that colonies of Bacillus cereus are readily identified and confirmed by microscopic examination.

The primary diagnostic features of the medium are the colonial appearance, precipitation of hydrolyzed lecithin and the failure of Bacillus cereus to utilize mannitol. The typical colonies of Bacillus cereus are crenated, about 5mm in diameter and have a distinctive turquoise to peacock blue color surrounded by a good egg yolk precipitate of the same color. These features distinguish Bacillus cereus from other Bacillus spp. except Bacillus thuringiensis.

Not all products are available for sale in all territories. Please inquire.

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