Continuous suspended cell culture of Mentha piperita in cell-recycled air-lift bioreactor

A cell-recycled air-lift bioreactor was studied for its performance in cultivation of Mentha piperita cells producing essential oils. The reactor system sustained a stable operation over 30 days with the aid of a cell settler. The maximum cell concentration reached 50% packed cell volume and it occurred at the dilution rate of 0.27 day-1. Volumetric productivity of essential oils in this system was substantially higher than that obtainable from batch culture.