The inhibitory effect of ethanol on ethanol production byZymomonasmobilis

✍ Scribed by Hugh Burrill; Horst W. Doelle; Paul F. Greenfield

• Publisher: Springer Netherlands
• Year: 1983
• Tongue: English
• Weight: 339 KB
• Volume: 5
• Category: Article
• ISSN: 0141-5492
• DOI: 10.1007/bf00131285

✦ Synopsis

In an effort to establish the reasons for the limitations in the final ethanol concentration of Zymomonas mobilis fermentation, the effects of CO 2 and ethanol on the fermentation were investigated using continuous and fed-batch cultivation systems. The nucleation and stripping out of C02 from the fermenter using diatomaceous earth or nitrogen gas or both exhibited a profound effect on the glucose uptake rate during the early stages of fed-batch fermentation, but did not improve final ethanol yields. The addition of ethanol together with above mentioned experiments confirmed conclusively that ethanol inhibition is responsible for the final ethanol concentration obtainable during Zymomonas mobilis fermentation. The final concentration lies between 90 and Ii0 gl -I or approximately 12-15% (v/v) ethanol.