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Aurora
red+ Because most Salmonella produce hydrogen sulfide from sodium thiosulfate, the colonies will turn black in the presence of ferric ammonium citrate, which will differentiate Salmonella from Shigella+
Preparation
Ingredients
yeast extract
xylose
lysine
lactose
sucrose
sodium deoxycholate
sodium thiosulfate
ferric ammonium citrate
phenol red
agar
Procedure:
1+ Add hot distilled water slowly to the powdered mixed ingredients to make 500 ml solution
2+ Shake it vigorously to dissolve
3+ when is totally dissolved, put it in a hot water bath (80-90º C) shake it every 5min while
adding the agar till the agar is clearly dissolves
Specialized Media
A large variety of specialized media have been created for the detection of specific organisms that may be fastidious or typically present in large mixtures of organisms+
Buffered charcoal yeast extract (BCYE)
agar
Buffered Charcoal Yeast Extract (BCYE)
Agar is an enrichment medium which is
used for the isolation and cultivation of
Legionella species from environmental
samples and clinical specimens+
BCYE agar provides L-Cysteine and
other nutrients required for the growth
of Legionella spp+
Preparation
Ingredients
Yeast extract
L-Cysteine
activated charcoal
Ferric Pyrophosphate
ACES buffer
Ketoglutarate mono-potassium salt
Agar
Fig 1.20: BCYE Agar (wikimedia.org, 2014)