Prior to cultivation the hydrolysates were centrifuged (10 min,
RCF 4000), filtered (0.45 lm) and enriched with nitrogen and magnesium
compounds. Nitrogen was supplemented in the form of
either diammonium hydrogen phosphate (NH4)2HPO4 (7 g dm3
),
urea CO(NH2)2 (3.2 g dm3
), or as a mixture (3.5 g dm3
(NH4)2HPO4 and 1.6 g dm3 CO(NH2)2). Magnesium was added as
MgSO47H2O at a dose of 0.15 g dm3 of the medium. The pH
was then adjusted (pH = 5 ± 0.1).
2.2