High productivity continuous ethanol fermentation with a flocculating mutant strain of Zymomonas mobilis

Zymomonas mobilis as a model system for production of biofuels and biochemicals

“…For example, the strategy of flocculating of microbial cells to increase cell densities and productivities has been widely investigated for the production of ethanol in the cultivation of Z. mobilis (Fein et al ., ). An ethanol volumetric productivity of 80 g l −1 h −1 was attained along with an ethanol titre of 47 g l −1 in a continuous cultivation employing a flocculating Z. mobilis WR6 (Fein et al ., ). A continuous culture using immobilized Z. mobilis cells to produce levan in Ca‐alginate gel beads was investigated, with a maximum levan titre of 31.8 g l −1 and productivity of 6.6 g l −1 h −1 achieved in a packed bed fermenter (Silbir et al ., ).…”

The role of cellulosics in chitosan flocculation of Zymomonas mobilis

“…However, such natural floes are easily disrupted ( Fein et al, 1983 ). Ghommidh and Bu'Lock (1988) sought to produce more stable floes through the addition of synthetic polymeric flocculants to non-flocculent cultures of Z. mohilis.…”

Controlling Morphological Instability of Zymomonas mobilis Strains in Continuous Culture

“…By introducing small changes into the design of the system, we were able to control the morphological behavior of Z. mobilis in continuous culture, enabling kinetic studies to be carried out with both variant types under steady-state conditions. The results of the kinetic studies are reported elsewhere (8).…”