# 887: OS MEDIUM


## Main sol. 887

256	mg	NaCl	
1.7	mg	KH2PO4	
0.8	mg	CaCl2 x 2 H2O	
10.3	mg	H3BO3	
23	mg	Na2SO4	
0.3	mg	NaNO3	
15	mg	KCl	
0.1	mg	FeCl3 x 6 H2O	
0.06	mg	MnSO4 x 4 H2O	
10	ml	**Modified Wolin's mineral solution II**	
1000	ml	Distilled water	

1. Sparge medium with 100% N2 gas mixture for 30 min to make anoxic.
2. Adjust pH to 7.0 with H2SO4.
3. Fill 10 ml medium into 100 ml Serum bottles under a stream of H2/CO2 gas and seal with a rubber stopper.
4. Autoclave at 121 °C for 20 min.
5. After autoclaving add the following (e.g., from sterile stock solutions)

1	g/l	Na2S2O3 x 5 H2O (10% in H2O)	
1	g/l	NaHCO3 (5 % in H2O)	

6. Adjust the gas atmosphere strain specifically.


## Modified Wolin's mineral solution II

1.5	g	Nitrilotriacetic acid	
3	g	MgSO4 x 7 H2O	
0.5	g	MnSO4 x H2O	
1	g	NaCl	
0.1	g	FeSO4 x 7 H2O	
0.18	g	CoSO4 x 7 H2O	
0.1	g	CaCl2 x 2 H2O	
0.18	g	ZnSO4 x 7 H2O	
0.01	g	CuSO4 x 5 H2O	
0.02	g	AlK(SO4)2 x 12 H2O	
0.01	g	H3BO3	
0.01	g	Na2MoO4 x 2 H2O	
0.025	g	NiCl2 x 6 H2O	
0.3	mg	Na2SeO3 x 5 H2O	
1000	ml	Distilled water	

1. First dissolve nitrilotriacetic acid and adjust pH to 6.5 with KOH, then add minerals. Adjust final to pH 7.0 with KOH.