We have used MV (Marine medium with Vitamins) for many years as a standard medium for marine benthic algae.
This is the medium named ESI by Tatewaki (1966) but supplemented with vitamins.
The salinity is indicated by a number after the abbreviation MV (eg. MV30 = MV-medium based on 30 ‰ filtered sea water).
1. P II trace metal stock solution
|ZnCl2 (0.1 g/100 mL)||10 mL|
|CoCl2•6H2O (0.1 % g/100mL)||4 mL|
|dH2O||to 1000 mL|
The P II trace metal stock solution is divided in 250-mL lots, autoclaved and stored refrigerated.
2. ESI stock solution
|KI (0.1 g/100 mL)||1.3 mL|
|P II trace metal stock solution||250 mL|
The solution is adjusted to pH 7.
After adjusting the pH, the ESI stock solution is dispensed in 20-mL lots, autoclaved and stored refrigerated.
3. Vitamin stock solution
|Thiamine HCL(Vitamin B1)||200 mg|
|0.01 % Biotin||5 mL|
|0.01 % Cyanocobalamine(Vitamin B12)||5 mL|
|dH2O||to 1000 mL|
If the vitamin stock solution is to be autoclaved, pH must first be adjusted to 5.
The vitamin stock solution is dispensed in appropriate lots and stored frozen.
4. Final preparation of MV-medium
a) To each liter of sea water (filtered and adjusted to the desired salinity) add 20 mL ESI Stock Solution
b) The ESI-enriched sea water is pasteurized at 73°C and cooled as quickly as possible to avoid precipitation.
c) One mL of the vitamin stock solution is added to the cooled enriched sea water.
It is sometimes desirable to sterilize the vitamin stock solution by autoclaving and to add the vitamins aseptically to the enriched sea water. Alternatively add unsterilized vitamin stock solution through a 0.2-µm sterile membrane filter mounted on a disposable syringe.
d) The medium is then dispensed aseptically to sterile culture tubes, etc. and stored refrigerated.
Notice: We now routinely add the ESI stock solution and vitamins to the sea water and autoclave rather than pasteurize the mixture.
Christensen, T. 1982. Alger i Naturen og i Laboratoriet. 136 pp. 1. ed. Nucleus. (In Danish).
Tatewaki, M. 1993. 1966. Formation of a crustaceus sporophyte with unilocular sporangia in Scytosiphon lomentaria. Phycologia 6(1), 62-66.