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Physiological requirements for growth and competitiveness of Dekkera bruxellensis under oxygen‐limited or anaerobic conditions
Author(s) -
Blomqvist Johanna,
Nogué Violeta Sànchez,
GorwaGrauslund Marie,
Passoth Volkmar
Publication year - 2012
Publication title -
yeast
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.923
H-Index - 102
eISSN - 1097-0061
pISSN - 0749-503X
DOI - 10.1002/yea.2904
Subject(s) - yeast , biology , fermentation , anaerobic exercise , population , saccharomyces cerevisiae , food science , sugar , oxygen , biochemistry , ethanol fuel , facultative , botany , chemistry , physiology , demography , organic chemistry , sociology
The effect of glucose and oxygen limitation on the growth and fermentation performances of Dekkera bruxellensis was investigated in order to understand which factors favour its propagation in ethanol or wine plants. Although D. bruxellensis has been described as a facultative anaerobe, no growth was observed in mineral medium under complete anaerobiosis while growth was retarded under severe oxygen limitation. In a continuous culture with no gas inflow, glucose was not completely consumed, most probably due to oxygen limitation. When an air/nitrogen mixture (O 2 ‐content ca. 5%) was sparged to the culture, growth became glucose‐limited. In co‐cultivations with Saccharomyces cerevisiae , ethanol yields/g consumed sugar were not affected by the co‐cultures as compared to the pure cultures. However, different population responses were observed in both systems. In oxygen‐limited cultivation, glucose was depleted within 24 h after challenging with S. cerevisiae and both yeast populations were maintained at a stable level. In contrast, the S. cerevisiae population constantly decreased to about 1% of its initial cell number in the sparged glucose‐limited fermentation, whereas the D. bruxellensis population remained constant. To identify the requirements of D. bruxellensis for anaerobic growth, the yeast was cultivated in several nitrogen sources and with the addition of amino acids. Yeast extract and most of the supplied amino acids supported anaerobic growth, which points towards a higher nutrient demand for D. bruxellensis compared to S. cerevisiae in anaerobic conditions. Copyright © 2012 John Wiley & Sons, Ltd.