DESIGN OF A CONTINUOUS ROTATING ANNULAR BIOREACTOR FOR IMMOBILIZED-CELL FERMENTATIONS

A novel continuous annular packed-bed bioreactor for immobilized-cell fermentation was developed. In the operation of this bioreactor, the n ongrowth medium was added to the immobilized-cell phase evenly and con tinuously through a stationary inlet. The nutrient medium, on the othe r hand, was fed to the bed through a rotating nozzle. Therefore, addit ion of the nutrient medium to every local point in the immobilized-cel l phase was only intermittent whereas the whole process was continuous . For an alpha-amylase fermentation by kappa-carrageenan gel-immobiliz ed Bacillus amyloliquefaciens cells, this bioreactor was found to be s uitable for the control of cell growth and maintenance of cell product ivity. Moreover, the volumetric productivity of a-amylase obtained in this bioreactor could be much higher than in a shake flask, if the rea ctor was properly operated.