The pH was controlled in the
reactor at pH 6 by titration with NH4OH. For
this study, the volume of medium used was 700 ml
and that of insoluble biocatalyst, 350 ml. Once the
sugar was completely utilized, the reactor was
emptied, washed by circulating 700 ml of 0.9%
NaCl solution, and fresh medium (synthetic or
WP) containing 100 g l−1sugar was pumped in.