The fermentation times for the immobilized biocatalyst
BSG1 were generally lower than those for the other two
immobilized biocatalysts at both temperatures (Table 1).
Also, ethanol concentration and ethanol productivities were
higher in case of BSG1 biocatalyst. It was important to note
that the immobilized biocatalyst retained its fermentation
activity at 30 and 20 °C. At 30 °C, the fermentation time during
repeated fermentation batches (1 up to 6 batch) by BSG1 immobilized biocatalyst continuously decreased,
which gave ethanol productivity increase. The results demonstrated
that fresh BSG supported yeast immobilization
without additional nutrients in the used glucose medium. In
addition, the deligniWcation step could be avoided since it
did not seem to improve kinetics and increases costs.