Continuous production of bacitracin by immobilized living whole cells of Bacillus sp.

Whole cells of Bacillus sp., a bacitracin‐producing bacteria, were immobilized in polyacrylamide gel. The continuous production of bacitracin by an immobilized whole‐cell‐containing air‐bubbled reactor was examined with 0.5% peptone solution. The bacitracin productivity (28 units/ml/hr) obtained with this system was higher than that with a batch system. The effluent bacitracin concentration increased with increasing aeration rate and reached a steady‐state maximum above the aeration rate of 3.0 liter/min. A high bacitracin productivity was retained for at least eight days when the gel was washed with sterilized saline at a flow rate of 250 ml/hr for 2 hr once a day. The half‐life of the immobilized whole‐cell system was about 10 days. Bacitracin productivity by the immobilized whole‐cell reactor was higher than that by a conventional continuous fermentation process at high dilution rates.