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BAM Media M91: MacConkey Agar

BAM Media M91: MacConkey Agar

January 2001

Bacteriological Analytical Manual

Proteose peptone
or polypeptone
3 g
Peptone or gelysate 17 g
Lactose 10 g
Bile salts No. 3
or bile salts mixture
1.5 g
NaCl 5 g
Neutral red 0.03 g
Crystal violet 0.001 g
Agar 13.5 g
Distilled water 1 liter

Suspend ingredients and heat with agitation to dissolve. Boil 1-2 min. Autoclave 15 min at 121°C, cool to 45-50°C, and pour 20 ml portions into sterile 15 × 100 mm petri dishes. Dry at room temperature with lids closed.

DO NOT USE WET PLATES. Final pH, 7.1 ± 0.2.


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