Simultaneous nitrogen fixation and ethanol production by Zymomonas mobilis.
J Biotechnol
; 314-315: 41-52, 2020 May 20.
Article
en En
| MEDLINE
| ID: mdl-32259548
This work reports on production of ethanol with simultaneous fixing of nitrogen (N2) using the anaerobic bacterium Zymomonas mobilis DSM 473. A batch fermentation with an initial glucose concentration of 50 g L-1, an initial pH of â¼5.5, an inoculum size of 10% by volume and a N2 feeding rate of 50 mL min-1 without mechanical agitation was found to provide the highest ethanol productivity (0.401 g L-1 h-1). Ethanol yield on glucose exceeded 97% of the theoretical maximum. The nitrogen content of the microbial biomass was 10.4% w/w at 65 h and all of it was derived by fixation of dinitrogen. Repeated-batch fermentations were investigated for ethanol production using simultaneous nitrogen fixation. A 2-cycle repeated-batch fermentation lasting 71 h gave a maximum ethanol yield on glucose of 0.475 g g-1 and an ethanol productivity of 0.675 g L-1 h-1. The yield (0.415 g g-1) and productivity (0.638 g L-1 h-1) were reduced in a 3-cycle repeated batch operation lasting 94 h. The need to fix nitrogen did not reduce the final achievable ethanol concentration, or the ethanol yield on glucose, relative to fermentations provided with fixed nitrogen, but did reduce the ethanol productivity by â¼82% because less cell mass was produced.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Zymomonas
/
Etanol
/
Fijación del Nitrógeno
Idioma:
En
Revista:
J Biotechnol
Asunto de la revista:
BIOTECNOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Tailandia
Pais de publicación:
Países Bajos