Heat with agitation to dissolve. Adjust pH to 7.6 ± 0.2. Dispense 250 ml portions to 500 ml flasks. Autoclave 15 min at 121°C. Maintain medium at 50°C before use. Dehydrated SFP agar base (Difco) is satisfactory for base.

D-cycloserine solution

Dissolve 1 g D-cycloserine (white crystalline powder) in 200 ml of distilled water. Sterilize by filtration and store at 4°C until use. D-cycloserine powder is available from Sigma Chemical Co., St. Louis, MO.

Final medium

For pour plates, add 20 ml of D-cycloserine solution to 250 ml base. To prepare prepoured plates containing egg yolk, also add 20 ml of 50% egg yolk emulsion (M51). Mix well and dispense 18 ml into 15 x 100 mm petri dishes. Cover plates with a towel and let dry overnight at room temperature before use.

Hypertext updated by rim/cjm 2005-OCT-21