1. Our chromogenic medium is the only chromogenic agar that uses the virulence factor, PIPLC enzyme for detection.
2. Highly selective/differential detection system identifies only the pathogenic Bacillus species (B.c. & B.t.). Sensitivity for B. cereus/B. thuringiensis is 100% – no false negatives. Only a small percent of Enterococcussp., Staphylococcus sp. and Streptococcus grew on our medium (pinpoint white colonies).
3. Competitors’ chromogenic media use the β-glucosidase reaction in which other non-B. cereus/B. thuringiensis species will grow on the agar and produce false positives.
4. MYP (Mannitol Egg Yolk Polymyxin) agar is commonly used plating medium and is dependent on lecithinase activity on the egg yolk in the agar. There is a tendency of zones from individual colonies to coalesce which often causes difficulty in colony enumeration – a major drawback of the medium. Also, other Bacillus sp. that grow on MYP besides B. cereus/B. thuringiensis will give positive egg yolk reactions – creamy white with egg yolk precipitate.
5. Unlike our medium, MYP will require supplemental tests to confirm B. cereus/B. thuringiensis making it very costly.
6. In contrast to the lecithinase reaction in MYP where colony coalescing can adversely affect enumeration of B. cereus/B. thuringiensis, the water insoluble chromogen in our medium colors only the colonies and positively identifies B. cereus/B. thuringiensis.
7. The shelf life of prepared plates remains stable for at least 60 days, stored in the dark at 2-8°C. One bottle of plating medium powder and two boxes of supplements will make approximately 230 plates.