Base Medium
Yeast Extract (BD 212750)……………………………10.0 g
Charcoal (Sigma C-5510)……………………………..2.0 g
ACES Buffer……………………………………………10.0 g
DI Water…………………………………………………980.0 ml
Adjust pH to 6.90 +/- 0.05 using KOH (pH is critical). Autoclave at 121?C. Cool to 50?C.
Aseptically add Solutions A and B (see below). Recheck pH and adjust if necessary.
Allow sample to cool to room temperature before reading pH. Keep charcoal in suspension when dispensing. For solid medium, add 17 grams of Agar to base medium above.
**Note: Medium should be wrapped in foil to protect from light
**Note: Be sure to allow solid products adequate time to dry (at least two days).Agar will become soft and unusable if it does not dry properly.
Solution A
L-Cysteine HCl……………………………………………0.4 g
DI Water…………………………………………………...10.0 ml
Filter Sterilize.
Solution B
Fe-pyrophosphate……………………………………….0.25g
DI Water…………………………………………………..10.0 ml
Filter Sterilize.
Note: Keep soluble Ferric pyrophosphate dry and in the dark. Do not use if the chemical loses its green color and becomes brown or yellow. Do not heat over 60?C to dissolve. The mixture dissolves readily in a 50?C water bath.