KM0084 – Bacillus Cereus Agar (MYP)

//KM0084 – Bacillus Cereus Agar (MYP)

KM0084 – Bacillus Cereus Agar (MYP)

Bacillus cereus (MYP) agar is intended for the selective enumeration of Bacillus cereus in food samples. This medium utilizes two reactions namely mannitol fermentation and lecithinase production to differentiate Bacillus cereus from other related species. As B. cereus is mannitol negative the colonies are pink in colour due to the presence of the phenol red pH indicator. Lecithinase production (from the addition of egg yolk) is indicated by a white precipitate around the colonies. This medium meets the requirements of ISO 7932:2004.
Beef extract and peptone provide the required carbon, nitrogen and vitamins. Sodium chloride helps maintain the osmotic balance and phenol red is the pH indicator. Mannitol is a fermentable carbohydrate. The medium is made selective by the inclusion of polymyxin B sulphate (LS0020).

NB: This is a basic medium only and contains no additional supplement. It should be noted that some Proteus spp. and Gram-positive cocci may grow on this medium.

Related Supplements :
LS0020 Bacillus cereus Selective Supplement, BM0140 Egg Yolk Emulsion

SKU: KM0084 Category:

Additional Information

Shelf Life (days)

Storage Temp (°C)

Dehydrated Medium Appearance

Prepared Medium Appearance

Dehydrated Medium Colour

Prepared Medium Colour

Dehydrated PH

Prepared PH

Product Description

Organisms Ref. No Result
Bacillus cereus NCTC 10320 Growth, pink colonies with preciptation halo
Bacillus subtilis NCTC 10400 Growth, yellow colonies with no preciptation halo
Escherichia coli NCTC 12241 Inhibited

 

Formula*

g/L
Beef Extract 1.0
Peptone 10.0
Mannitol 10.0
Sodium Chloride 10.0
Phenol Red 0.025
Agar 15.0
Total 46.0
*Adjusted/supplemented as required to meet performance requirements

Preparation

Suspend 46g of the medium in one litre of deionised / purified water. Allow the medium to soak whilst mixing for 10 minutes. Heat with frequent agitation and boil for one minute to completely dissolve the medium. Sterilise at 121°C for 15 minutes. Cool to 45-50°C and aseptically add 100ml of egg yolk emulsion (BM0140) and required number of vials of B. cereus selective supplement (LS0020). Homogenize gently and dispense into appropriate sterile containers.