CAYE Broth Base

CAYE Broth Base

Cat. No. 1.00060.0100
100 g

Medium for culturing pathogenic E.coli (VTEC) to enhance verotoxin production.

Mode of Action	Typical Composition
Preparation	Experimental Procedure and Evaluation
Quality Control	Literature
Additives

Mode of Action
Casaminoacids and yeast extract promote the growth of verotoxin producing E.coli. Trace elements and a high pH value additionally support the formation of verotoxins.

Typical Composition (g/liter)
Casaminoacids 20.0; yeast extract 6.0; D(+)glucose 2.5; sodium chloride 2.5; di-potassium hydrogenphosphate 8.71; magnesium sulfate 0.05; manganese chloride 0.005.

Preparation
Suspend 7.95 g in 200 ml of purified water. Heat to boiling to dissolve completely, swirling regularly.

Autoclave (15 min at 121°C).

Cool the medium to room temperature. Aseptically add the contents of one vial of CAYE Broth Supplement to the CAYE Broth Base. Fill 1 ml into sterile test tubes (with agitation).

pH: 8.5 + 0.2 at 25°C.

The prepared broth is clear and light brown. Occuring precipitate does not have any effect on the performance of the medium.

Experimental Procedure and Evaluation
IPick 5-6 typical colonies from the isolation medium and transfer into the prepared tube.

Incubation: 6 hours at 37°C.

Quality control

Test strains	Verotoxin Production
Escherichia coli 0157:H7 43889	VT 1 negative	VT 2 positive
Escherichia coli 0157:H7 73890	VT 1 positive	VT 2 negative
Escherichia coli 0157:H7 43888	VT 1 negative	VT 2 negative
Escherichia coli 0157:H7 43895	VT 1 positive	VT 2 positive

Additives

EMD Cat. No.	Product	Pack Size
1.00051.0001	CAYE Supplement	16 vials

Literature

AUBERTIN, E., AUBEL, E., et GENEVOIS, L.: A propos de la culture des anaérobies strict en milieu, aérobie. - Compt. rend. Soc. Biol. (PARIS), 98; 957-959 (1928).
BREWER, J.H.: Clear liquid medium for the "aerobic" cultivation of anaerobes. - .J. Amer. Med. Ass., 115; 598-600 (1940).
BREWER, J.H.: A new Petri dish and technique for use in the cultivation of anaerobes and microaerophiles. - Science, 95; 587 (1942).
QUASTEL, J.H., a STEPHENSON, M.: Experiments on "strict" anaerobes: I. The relationship of B. sporogenes to oxygen . - Biochem. J., 20; 1125-1137 (1926).