Isolating B. cereus

Burki Burki at amm.unibe.ch
Thu Dec 11 11:41:08 EST 1997

Ed wrote:
> > G'day John
> either TSB or ND + polymyxin (enrichment or MPN) or spread plate
> using PEMBA agar (Bacillus cereus selective agar) and confirmation
> via Holbrook stain for spore location/type and lipid inclusions
> Ed from downunder.

Since the spore stain is quite messy you might also want to confirm your
B. cereus by the following standard tests:

- Nitrate-Reduction			POS
- Hemolysis on Sheep Blood Columbia	POS
- Gelatinase-Test			POS

These are the official confirmation tests in the Swiss Book of Food
Microbiology and, I believe, in the FDA Manual.
They do not, however, differentiate between B. cereus and B.
thuringensis. They can be distiguished by a toxin stain (also messy...)


Didi Burki, Berne/Switzerland
(to reply please replace amm by imm)

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