an increase in productivity can be achieved by either supplementing the medium with nutrients such as yeast extract or by allowing more cells to build up in the reactor with more consecutive batch fermentation runs.
It was, however, not the purpose of this study to increase productivity.
Instead, the focus was on the reactor long-term stability using corn meal as the sole carbon source.
It should be noted that productivity did increase dramatically from the free-cell culture to immobilized-cell fermentation, which was consistent with our previous findings with the FBB.