PROCESS ANALYSIS OF L-LYSINE FERMENTATION WITH CORYNEBACTERIUM-GLUTAMICUM UNDER DIFFERENT OXYGEN AND CARBON-DIOXIDE SUPPLIES AND REDOX POTENTIALS

The production of L-lysine by a homoserine and leucine requiring strai n of Corynebacterium glutamicum ATCC 21513 was studied. O-2 limitation caused a decrease in both substrate consumption rate and the conversi on efficiency of substrate to L-lysine, concomitant with formation of L-lactate and isobutyric acid. The maximum conversion rate into L-lysi ne was obtained at 30-35% dissolved oxygen saturation and at a redox p otential up to -140 mV Increased CO2 levels increased biomass yield an d considerably decreased formation of organic acids. Under optimal oxy gen conditions, without CO2 addition a decrease of 33% in isobutyric a cid and 26% in lactate production and an increase of 20% in L-lysine p roduction were obtained compared with cultures grown under 15-20% of O -2 saturation.