Ss. Kesava et al., PRODUCTION OF ETHANOL BY ZYMOMONAS-MOBILIS - THE EFFECT OF BATCH STEP-FEEDING OF GLUCOSE AND RELEVANT GROWTH-FACTORS, Process biochemistry, 30(1), 1995, pp. 41-47
Ethanol production by Zymomonas mobilis (ATCC 10988) was studied by us
ing different concentrations offglucose (50-300 g/litre). A glucose co
ncentration of 50-150 g/litre showed the highest ethanol-yield efficie
ncy. Step-feeding of glucose was attempted to increase ethanol product
ion and to reduce substrate inhibition. A step-feeding system for a to
tal glucose concentration of 200 g/litre was found suitable. The speci
fic growth rate was reduced as the number of steps increased. The effe
ct of inoculum age, yeast extract, and peptone on the step-feeding sys
tem was studied. A suitable combination of yeast extract and peptone w
as selected on the basis of the central-composite-rotatable-design (CC
RD) procedure.