Fermentative Production of Bacterial Cellulose
All fermentations were conducted under sterile conditions in 250 mL Erlenmeyer flasks with 50 mL
working volume at 30 °C. The volume of the inoculum was 10% (v/v) and the pH value of the broth was
adjusted to 6 using 5 M NaOH. The flasks were initially incubated at 100 rpm for 1–2 days and then
statically until the end of the fermentation (15 days).
The first series of fermentations was carried out using modifications of the HS media (substitution
of glucose with other carbon sources, such as xylose, sucrose, fructose, lactose and crude glycerol).
The initial FAN concentration in all cases was ~350 mg/L. Moreover, in the case of BC production
using crude glycerol as carbon source, the effect of different initial FAN concentration was evaluated.
More specifically, concentrations of 5, 7.5 and 10 g/L of yeast extract and peptone were used in order
to achieve initial FAN concentrations of 360, 500 and 700 mg/L, respectively. SFM hydrolysates were
diluted with tap water in order to adjust the initial FAN concentration. SFM hydrolysates (together with
crude glycerol) and FRW hydrolysates were applied as fermentation media for the production of BC.