we also noticed the maximum level of oxalic acid
(1.24 ± 0.2 mM) in the culture medium of G. applanatum.
Apart from oxalic acid, the presence of succinic acid and
tartaric acid was observed during the growth of G. applanatum, but these two acids were detected only
in trace
amounts (Fig. 3). The highest concentration of succinic
acid (0.7 ± 0.01 mM) and tartaric acid (3.55 ± 0.03 mM)
was observed only on the 11th day of cultivation of G.
applanatum at 37 °C. T. palustris grew optimally in all the
tested temperatures and the maximum dry weight of
biomass was obtained at 37 °C (0.38 ± 0.02 g/L), while
the maximum amount of exopolysaccharides was observed
during the growth at a temperature of 20 °C (19.1 ± 1.2 g/
L). It was observed that the concentration of oxalic acid in
the culture media of T. palustris increased when the culture
temperature increased from 20 to 37 °C, and the highest
amount of oxalic acid was obtained in the cultures growing
at 37 °C (21.1 ± 1.1 mM). The results indicate that the
optimal temperature for the cell growth of T. palustris is
not consistent with the optimal temperature for the secretion of oxalic acid.