# 838: GEOANAEROBACTER MEDIUM


## Main sol. 838

10	g	Ferric citrate monohydrate	
0.6	g	KH2PO4	
0.3	g	NH4Cl	
0.5	g	MgSO4 x 7 H2O	
0.1	g	CaCl2 x 2 H2O	
1	ml	**Trace element solution SL-11**	
1	ml	**Selenite-tungstate solution**	
1.5	g	Na2CO3	
0.8	g	Na-acetate	
0.8	g	Na-ascorbate	
1000	ml	Distilled water	

1. First dissolve ferric citrate by heating the water under continuous stirring. After cooling to room temperature adjust the pH to 6.0, then add and dissolve the remaining ingredients, except carbonate, acetate and ascorbate. Sparge medium with 80% N2 and 20% CO2 gas mixture for 30 - 45 min to make it anoxic, then dispense under the same gas atmosphere into anoxic Hungate-type tubes or serum vials and autoclave. After autoclaving add acetate and ascorbate from sterile anoxic stock solutions prepared under 100% N2 gas and carbonate from a sterile anoxic stock solution prepared under 80% N2 and 20% CO2 gas mixture. Prior to inoculation check the medium pH and adjust to 6.8, if necessary.


## Trace element solution SL-11

5.2	g	Na2-EDTA x 2 H2O	
1.5	g	FeCl2 x 4 H2O	
70	mg	ZnCl2	
100	mg	MnCl2 x 4 H2O	
6	mg	H3BO3	
190	mg	CoCl2 x 6 H2O	
2	mg	CuCl2 x 2 H2O	
24	mg	NiCl2 x 6 H2O	
36	mg	Na2MoO4 x 2 H2O	
1000	ml	Distilled water	

1. Dissolve EDTA in 800 ml distilled water, adjust pH to 7 using 2 N NaOH and add ferrous chloride. After ferrous chloride has dissolved add other compounds. Finally adjust pH to 6.0 and bring volume to 1000 ml. 


## Selenite-tungstate solution

0.5	g	NaOH	
3	mg	Na2SeO3 x 5 H2O	
4	mg	Na2WO4 x 2 H2O	
1000	ml	Distilled water