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  1. Science & Research (Food)

BAM Media M39: Christensen Citrate Agar

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.