Bacterial Cellulose Production by Fed‐Batch Fermentation in Molasses Medium

Batch and fed‐batch fermentations for bacterial cellulose (BC) production using molasses as a carbon source by Acetobacter xylinum BPR2001 were carried out in a jar fermentor. For improvement of BC production, molasses was subjected to H 2 SO 4 –heat treatment. The maximum BC concentration by this treated molasses increased 76%, and the specific growth rate increased 2‐fold compared with that by untreated molasses. In batch fermentation, when the initial sugar concentrations of H 2 SO 4 –heat‐treated molasses were varied from 20 to 70 g/L, the highest value of maximum BC concentration of 5.3 g/L was observed at 20 g/L. BC production in intermittent fed‐batch (IFB) fermentation was conducted referring to the data in batch fermentation, and the highest BC production of 7.82 g/L was obtained when 0.2 L of molasses medium was added five times. When continuous fed‐batch (CFB) fermentations were conducted, maximum BC concentration was obtained with a feeding rate of 6.3 g‐sugar/h, which was derived from the optimal IFB experiment.