Production of L-glutamic Acid by Immobilized Cell Reactor of the Bacterium Corynebacterium glutamicum Entrapped into Carrageenan Gel Beads

Immobilized cell reactor of the bacterium Corynebacterium glutamicum entrapped into carrageenan gel beads was constructed and used for the investigation of batch, fed-batch and continuous production of L-glutamic acid from nutritionally enriched sugarcane molasses. High final L-glutamic acid concentration (>93 g l ) was achieved, in batch fermentation, but with low productivity of 3.8 g l h . Repeated batch 1 1 1 fermentation runs utilizing the immobilized cells for L-glutamic acid production was unsatisfactory. The best results were obtained when the immobilized cell bioreactor was operated in a continuous mode and both dilution rate and penicillin supplementation were manipulated. At D of 0.4 h and with 20 U ml of the 1 1 antibiotic penicillin in feeding medium, up to 73 g l of L-glutamic acid were recovered in reactor effluent with 1 a yield of 75.7% and volumetric reactor productivity of 29.1 g l .h. 1