The SSF reaction mixtures consisted of 8 g of the pretreated
aquatic plant samples (previously autoclaved for
20 min at 121 C), filter-sterilized cellulase (20 FPU (g substrate)
1) solubilized in 0.1 M sodium phosphate, the basal
medium and 5 ml microbial inoculum to give the same concentration
as that of the SHF experiment. The initial pH of
the SSF mixture was adjusted to 5.0 for S. cerevisiae
NBRC 2346 or 6.0 for E. coli KO11. The SSF reaction
was carried out at 37 C in 125 ml conical flasks with
80 ml working volume. The flasks were sealed with rubber
stoppers through which hypodermic needles had been
inserted for exhaust of the produced CO2 and for sampling.
Samples were withdrawn through the needle, and analyzed
for contents of ethanol, sugars and degradation products
of sugars.