Medium data

Search for medium no. = [1364].

Unless otherwise stated, sterilize media by autoclaving at 121°C for 15 min.

1364 WIDDEL FRESHWATER MEDIUM WITH FORMATE AND ACETATE

NaCl	`1.0`	g
MgCl₂·6H₂O	`0.4`	g
CaCl₂·2H₂O	`0.1`	g
NH₄Cl	`0.25`	g
KH₂PO₄	`0.2`	g
KCl	`0.5`	g
Na₂SO₄	`4.0`	g
Resazurin	`0.5`	mg
Distilled water	`980.0`	ml

Mix components, adjust pH to 8 and autoclave under a N₂ gas atmosphere. After cooling, add the following solutions from sterile anaerobic stocks (autoclaved or *filter-sterilized):

Trace element solution (see Medium No. 439)	`1.0`	ml
Selenite-tungstate solution* (see Medium No. 431)	`1.0`	ml
Vitamin mixture solution* (see Medium No. 1363)	`2.0`	ml
1.0 M Sodium formate solution	`7.5`	ml
1.0 M Sodium acetate solution	`9.0`	ml

Readjust pH to 8, if necessary. Separately autoclave and dry iron metal (grain). Aseptically distribute the medium and iron metal into culture vessels (e.g., 10 ml medium and 100 mg iron in Hungate tubes) under a N₂ gas stream and seal with butyl rubber stoppers. Prior to use, add per liter the following solution:

5% Na₂S·9H₂O solution 2.0 ml