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In this section: Laboratory Methods (Food)

BAM Media M39: Christensen Citrate Agar

Media Index for BAM

January 2001

Bacteriological Analytical Manual

Sodium citrate	3 g
Glucose	0.2 g
Yeast extract	0.5 g
Cysteine monohydrochloride	0.1 g
Ferric ammonium citrate	0.4 g
KH₂PO₄	1 g
NaCl	5 g
Sodium thiosulfate	0.08 g
Phenol red	0.012 g
Agar	15 g
Distilled water	1 liter

Suspend ingredients, mix thoroughly and heat with occasional agitation. Boil about 1 min to dissolve ingredients. Fill 16 × 150 mm tubes 1/3 full and cap or plug to maintain aerobic conditions. Autoclave for 15 min at 121°C. Final pH, 6.9 ± 0.2. Before media solidify, incline tubes to obtain 4-5 cm slant and 2-3 cm butt. The Difco formulation does not include ferric ammonium citrate and sodium thiosulfate.

Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.

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