Cultivation of a filamentous mould in an airlift bioreactor

Abstract Cephalosporin C biosynthesis was investigated in a pilot‐plant external‐loop airlift bioreactor for evaluating the capacity of this bioreactor to surpass the problems which arise from the morphology of the mould and the rheology of the broth. Some of the results were compared with those obtained in a stirred tank bioreactor. The dilution and the use of static mixers was necessary to overcome the effects of the high viscosities. The oxygen transfer rate represented 84% of that in the stirred bioreactor, but the efficiency of the power utilization was higher. The specific productivity of Cephalosporin C is comparable to that obtained in the stirred tank bioreactor, but the average specific power consumption was found to be 2/3 of that in the stirred vessel.