# 521: DESULFOMONILE MEDIUM


## Main sol. 521

1	g	NH4Cl	
2	g	Na2SO4	
1	g	Na2S2O3 x 5 H2O	
1	g	MgSO4 x 7 H2O	
0.1	g	CaCl2 x 2 H2O	
0.5	g	KH2PO4	
1	ml	**Trace element solution SL-10**	
1	ml	**Selenite-tungstate solution**	
1	g	Yeast extract	
0.5	ml	Sodium resazurin (0.1% w/v)	
1	g	NaHCO3	
10	ml	**Vitamin solution**	
2.5	g	Na-pyruvate	
0.1	g	Na2S x 9 H2O	
1000	ml	Distilled water	

1. Dissolve ingredients (except bicarbonate, vitamins, pyruvate and sulfide), then sparge medium with 100% N2 gas for 30 - 45 min to make it anoxic. Dispense medium under same gas atmosphere into anoxic Hungate-type tubes or serum vials and autoclave. Complete the medium by adding vitamins, pyruvate and sulfide from sterile anoxic stock solutions prepared under 100% N2 gas atmosphere and bicarbonate from a sterile anoxic stock solution prepared under 80% N2 and 20% CO2 gas mixture. Stock solutions of vitamins and pyruvate are sterilized by filtration. Adjust pH of the complete medium to 6.8 - 7.0.
2. Note: Prior to inoculation 10-20 mg/l sodium dithionite (added from a 5% w/v solution freshly prepared under N2 and filter-sterilized) can be added to the medium to stimulate growth at the beginning.


## Vitamin solution

5	mg	Pyridoxine hydrochloride	
5	mg	Riboflavin	
5	mg	Calcium pantothenate	
5	mg	p-Aminobenzoate	
5	mg	Thioctic acid	
50	mg	Nicotinamide	
5	mg	Biotin	
5	mg	Folic acid	
5	mg	Vitamin B12	
5	mg	Haemin (dissolved in 0.1 N NaOH)	
20	mg	1,4-Naphthoquinone (dissolved in 0.1 N NaOH)	
1000	ml	Distilled water	


## Trace element solution SL-10

10	ml	HCl (25%)	
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	
990	ml	Distilled water	

1. First dissolve FeCl2 in the HCl, then dilute in water, add and dissolve the other salts. Finally make up to 1000.00 ml.


## Selenite-tungstate solution

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