Ethanol production from cheese whey permeate by Kluyveromyces marxianus UFV-3: a flux analysis of oxido-reductive metabolism as a function of lactose concentration and oxygen levels
In order to investigate the effect of lactose concentration and oxygen level on the growth and metabolism of Kluyveromyces marxianus UFV-3 in cheese whey permeate, batch cultures were conducted under aerobic, hypoxic, and anoxic conditions, with lactose at initial concentration ranging from 1 to 240...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2005 |
| País: | Brasil |
| Institución: | Universidade Federal de Viçosa (UFV) |
| Repositorio: | LOCUS Repositório Institucional da UFV |
| Idioma: | inglés |
| OAI Identifier: | oai:locus.ufv.br:123456789/22322 |
| Acceso en línea: | https://doi.org/10.1016/j.enzmictec.2005.01.018 http://www.locus.ufv.br/handle/123456789/22322 |
| Access Level: | acceso abierto |
| Palabra clave: | Kluyveromyces marxianus Whey Ethanol Lactose concentration Oxygen level Oxido-reductive metabolism |
| Sumario: | In order to investigate the effect of lactose concentration and oxygen level on the growth and metabolism of Kluyveromyces marxianus UFV-3 in cheese whey permeate, batch cultures were conducted under aerobic, hypoxic, and anoxic conditions, with lactose at initial concentration ranging from 1 to 240 g L^−1. The increase in lactose concentration increased ethanol yield and ethanol volumetric productivity, and has reduced cell yield. When lactose concentration was equal or above 50 g L^−1 and the oxygen levels were low, the ethanol yield was close to its theoretical value. Maximum ethanol concentrations attained in this study were 76 and 80 g L^−1 in hipoxia and anoxia, respectively. The lactose consumption rate in anoxia was greater than in aerobiosis and hipoxia. However, under anoxia, the lactose consumption rate of K. marxianus followed a saturation kinetics, which was not observed in hypoxia and aerobiosis. All oxygen levels investigated, showed a tendency for saturation of the ethanol production rate above 65 g L^−1 lactose. Ethanol production rate was also higher on anoxia. |
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