Intracellular ethanol and cell viability ofZymomonas mobilis during fed-batch alcoholic fermentation

  • F. P. de França
  • S. G. F. Leite
Research Papers

Summary

The effect of intracellular as well extracellular ethanol concentration on the viability ofZymomonas mobilis during a fed-batch fermentation was examined. The cells retained their viability until ethanol attained 69.5 ± 1.55 and 69 ± 1.6g/l for respectively, extracellular and intracellular values.Z. mobilis does not therefore accumulate ethanol in the cells. The number of dead cells increased after exposure to ethanol. The maximal efficiency of the fermentation was 95.5% (3.82 mol of ethanol-mol sucrose).

Keywords

Sucrose Fermentation Cell Viability Dead Cell Ethanol Concentration 

Contenu intra-cellulaire en éthanol et viabilité des cellules de Zymomonas mobilis pendant une fermentation éthanolique en milieu non renouvelé à alimentation étagée

Résumé

On a examiné l'effet de la concentration en éthanol tant inta- que extra-cellulaire sur la viabilité deZymomonas mobilis pendant une fermentation en milieu non renouvelé à alimentation étagée. Les cellules ont gardé leur viabilité jusqu'à ce que la concentration atteigne 69.5 ± 1.55 et 69 ±a 1.6 g/l respectivement pour les valeurs extra- et intra-cellulaires. Il en résulte queZymomonas mobilis n'accumule pas l'éthanol dans les cellules. Le nombre de cellules mortes augmentait après l'exposition à l'éthanol. L'efficience maximum de la fermentation était de 95.5% (3.82 mol d'éthanol/mol de sucrose).

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Copyright information

© Oxford University Press 1989

Authors and Affiliations

  • F. P. de França
    • 1
  • S. G. F. Leite
    • 1
  1. 1.Departamento de Engenharia Bioquimica da UFRJ Centro de TecnologiaRio de JaneiroBrasil

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