BY-PRODUCT FORMATION IN CELL-RECYCLED CONTINUOUS-CULTURE OF LACTOBACILLUS-CASEI

While the volumetric productivity of lactic acid increased in continuo us culture of Lactobacillus casei with cell recycle, enhanced formatio n of by-products such as acetate, formate, ethanol, and D-lactate was observed in the cell-recycled fermenter compared with a simple chemost at at a similar range of dilution rate. The increased formation of by- product which was significantly dependent on substrate limitation resu lted from a lower dilution rate rather than a high cell concentration in the cell-recycled fermenter.