Medium data

Search for medium no. = [574].

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

574 DB CHARACTERIZATION MEDIUM NO. 2

MDS salt water (see below)	`833.0`	ml
FeCl₂ solution (see Medium No. 187)	`1.0`	ml
Trace element solution (see Medium No. 187)	`1.0`	ml
Peptone (Oxoid)	`0.25`	g
Yeast extract (BD-Difco)	`0.05`	g

Add components and bring volume to 980 ml with distilled water. For preparation of solid medium, add 20 g/L agar (if necessary, use washed agar as described below). Autoclave, and after cooling, add the following solutions (filter-sterilized or *autoclaved) to the medium:

1 M NH₄Cl	`5.0`	ml
Potassium phosphate buffer* (see below)	`2.0`	ml
Vitamin solution (see below)	`3.0`	ml
1 M Sodium pyruvate solution	`10.0`	ml

Readjust pH to 7.0 - 7.5 with a sterilized 10% Na₂CO₃ solution, if necessary.
Washed agar:
Stir agar in distilled water and stand still for 30 min. Then, remove supernatant by decantation. Repeat the washing at least twice.
MDS salt water:

NaCl	`240.0`	g
MgCl₂·6H₂O	`30.0`	g
MgSO₄·7H₂O	`35.0`	g
KCl	`7.0`	g
1 M CaCl₂ solution	`5.0`	ml

Add components to distilled water and bring volume to 1.0 L. Adjust pH to 7.5 with 1 M Tris base.
Potassium phosphate buffer:

1 M K₂HPO₄	`83.4`	ml
1 M KH₂PO₄	`16.6`	ml

Combine the two solutions and check that pH is close to 7.5. Add an equal volume of distilled water.
Vitamin solution:

Biotin	`3.0`	mg
Folic acid	`4.0`	mg
Pyridoxine·HCl	`50.0`	mg
Thiamine·HCl	`33.0`	mg
Riboflavin	`10.0`	mg
Nicotinic acid	`33.0`	mg
DL-Calcium pantothenate	`17.0`	mg
Vitamin B₁₂	`17.0`	mg
p-Aminobenzoic acid	`13.0`	mg
Lipoic acid	`10.0`	mg
Distilled water	`1.0`	L