# 634c: RCM MEDIUM (N2/CO2)


## Main sol. 634c

38	g	dehydrated RCM medium	
0.5	ml	Sodium resazurin (0.1% w/v)	
1	g	Sodium carbonate	
1000	ml	Distilled water	

1. Dissolve dehydrated RCM medium (available from BD BBL, OXOID or MERCK) in distilled water and add 0.5 ml/l Na-resazurin solution (0.1% w/v), bring to the boil and cool to room temperature while sparging with 80% N2 and 20% CO2 gas mixture. Dispense medium under same gas atmosphere into anoxic Hungate-type tubes or serum vials and autoclave. Before use, add 1.0 g of sodium carbonate per liter medium from a sterile anoxic stock solution prepared under 80% N2 and 20% CO2 gas mixture. Check pH of medium after autoclaving and adjust pH to 6.8, if necessary.