A filter fermenter-apparatus and control equipment.

Laboratory equipment for cultivation of microorganisms with the removal of cell-free medium is described. Separation is accomplished by filtration through a membrane which is built into a top-driven fermenter. A system is presented which controls the flow rate by automatic cleaning of the filter. Flow schemes for batch and continuous fermentations are shown. The filter fermenter is useful when studying continuous culture with feedback of biomass or processes where growth or product formation rates are influenced by inhibitory metabolites. Results are presented from experiments with Saccharomyces cerevisiae, Pedicoccus pentosaceus, and Zymomonas mobilis.