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  1. Science & Research (Food)

BAM Media M12: Anaerobic Egg Yolk Agar

BAM Media M12: Anaerobic Egg Yolk Agar

January 2001

Agar base

Yeast extract 5 g
Tryptone 5 g
Proteose peptone 20 g
NaCl 5 g
Agar 20 g
Distilled water 1 liter

Autoclave 15 min at 121°C. Adjust pH to 7.0 ± 0.2.

2 Fresh Eggs
Treatment of eggs

Wash 2 fresh eggs with stiff brush and drain. Soak eggs in 70% ethanol for 1 h. Crack eggs aseptically. Retain yolks. Drain contents of yolk sacs into sterile stoppered graduate and discard sacs. Add yolk to equal volume of sterile 0.85% saline. Invert graduate several times to mix. Egg yolk emulsion (50%) is available commercially.

Preparation of medium

To 1 liter melted medium (48-50°C) add 80 ml yolk-saline mixture (available from Difco as Bacto Egg Yolk Enrichment 50%), and mix. Pour plates immediately. After solidification dry 2-3 days at ambient temperature or at 35°C for 24 h. Check plates for contamination before use. After drying, plates may be stored for a short period in refrigerator.

Storage 4°C

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