In comparison to the two-stage continuous fermentation where
the solvent volumetric productivity of 0.58 gABE l−1 h−1 and yield
of 0.24 gABE g−1 glucose was achieved, the new mode of fermentation
where the second-stage is operated as fed-batch, resulted
in higher volumetric productivity of 1.36 gABE l−1 h−1, yield of
0.3 gABE g−1 glucose and superior bioreactor specific productivities of
0.64 gABE g−1 cdw h−1 and 0.42 gbutanol g−1 cdw h−1.