(Larsen et al. 1994)
This medium is a slight modification of the Bs medium (Christensen 1982).
Bs is a modification of the classic freshwater media of Bold and Bristol.
1. Stock solutions
* Preferably freshly made
2. Soil extract
500 mL dry good quality but non-fertilized garden soil is placed in a large Erlenmeyer flask and wet with 1L glass distilled water. Approx. 0.5g CaCO3 (the amount is not critical) is added and the mixture is autoclaved. After autoclaving, let the mixture stand ca. 24h and filter through a normal laboratory paper filter. The filtration process easily takes one day. After filtration, the filtrate is filtered again, divided into lots of about 100 mL, autoclaved, and stored in the refrigerator. We do not use the extract before it has become clear. It usually takes several weeks. Be careful not stir up the sediment when using the extract.
3. Final preparation of NF2
About 500 mL H2O is filled into a 1000-mL volumetric flask.
Add 30 mL of the soil extract.
Add 1 drop of the FeCl3 solution.
Add 10 mL of each of the other 6 stock solutions.
Fill up with H2O to 1000 mL.
NF2/A (NF2 slant agar): The medium is solidified with 15 g agar per litre medium.
Christensen, T. 1982. Alger i Naturen og i Laboratoriet. 136 pp. 1. ed. Nucleus. (In Danish).
Larsen, N.H., Moestrup, Ø. & Pedersen, P.M. 1994. Catalogue 1994. Scandinavian Culture Centre for Algae & Protozoa. Department of Phycology. Botanical Institute. University of Copenhagen.