Cultivation of Bacillus thuringiensis in an airlift reactor with wire meshdraft tubes

An aeration strategy was proposed for foam control in an airlift reactor wi th double wire mesh draft tubes. The airlift reactor was employed in the cu ltivation of Bacillus thuringiensis for thuringiensin production. The aerat ion strategy involved two situations. If the foam rose and touched the foam probe, the air flow rate was dropped to a low value for a certain period. However, if the DO value was already below 10% of the saturation when the a ir flow rate was dropped, the conventional foam control was employed. The p roduction of thuringiensin based on the proposed strategy was up to 70% hig her than that of using the conventional cultivation method with addition of antifoam agents for foam control. (C) 2001 Elsevier Science B.V. All right s reserved.