Solution A: NH4Cl 535 mg KH2PO4 54 mg KCl 74 mg MgSO4 x 7 H2O 49 mg CaCl2 x 2 H2O 147 mg NaCl 584 mg Trace element solution 1 ml Cresol red solution 2 ml Distilled water ad 1000 ml
Autoclave, subsequently adjust pH of the medium to about 7.8 by addition of sterile 10% NaHCO3 (medium is turning from yellow to pink). Important: During growth, add NaHCO3 to readjust pH as soon as pH indicator changes to yellow. For stock cultures, 5 g l-1 CaCO3 (will stay as a precipitate) or 4.8 g l-1 HEPES may be added to keep pH neutral for a longer time. Aeration must be adjusted according to the density and activity of the culture. At low cell concentrations (which is the case most of the time) cells are sensitive to strong aeration (don’t shake the cultures). Trace element solution Distilled water 975 ml HCl, 1M 25 ml MnSO4 x 4 H2O 45 mg H3BO3 49 mg ZnSO4 x 7 H2O 43 mg (NH4)6 Mo7O24 x 4 H2O 37 mg FeSO4 x 7 H2O 973 mg CuSO4 x 5 H2O 25 mg Cresol red solution Cresol red 50 mg Distilled water 100 ml
