Assessing the potential of wild yeasts for bioethanol production
Journal article, 2015

Bioethanol fermentations expose yeasts to a new, complex and challenging fermentation medium with specific inhibitors and sugar mixtures depending on the type of carbon source. It is, therefore, suggested that the natural diversity of yeasts should be further exploited in order to find yeasts with good ethanol yield in stressed fermentation media. In this study, we screened more than 50 yeast isolates of which we selected five isolates with promising features. The species Candida bombi, Wickerhamomyces anomalus and Torulaspora delbrueckii showed better osmo- and hydroxymethylfurfural tolerance than Saccharomyces cerevisiae. However, S. cerevisiae isolates had the highest ethanol yield in fermentation experiments mimicking high gravity fermentations (25 % glucose) and artificial lignocellulose hydrolysates (with a myriad of inhibitors). Interestingly, among two tested S. cerevisiaestrains, a wild strain isolated from an oak tree performed better than Ethanol Red, a S. cerevisiae strain which is currently commonly used in industrial bioethanol fermentations. Additionally, a W. anomalus strain isolated from sugar beet thick juice was found to have a comparable ethanol yield, but needed longer fermentation time. Other non-Saccharomycesyeasts yielded lower ethanol amounts.

Thick juice

Bioethanol

Lignocellulose

Nectar

Wickerhamomyces anomalus

Author

Stefan Ruyters

KU Leuven

Vaskar Mukherjee

KU Leuven

Kevin J. Verstrepen

KU Leuven

VIB

Johan M. Thevelein

VIB

KU Leuven

Kris A. Willems

KU Leuven

Bart Lievens

KU Leuven

Journal of Industrial Microbiology and Biotechnology

1367-5435 (ISSN) 1476-5535 (eISSN)

Vol. 42 1 39-48

Subject Categories

Industrial Biotechnology

Biochemistry and Molecular Biology

Ecology

Microbiology

Areas of Advance

Life Science Engineering (2010-2018)

DOI

10.1007/s10295-014-1544-y

More information

Latest update

4/19/2021