Related Experiment Video
Updated: Feb 23, 2026
Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
Comparative assessment of fermentative capacity of different xylose-consuming yeasts
Henrique César Teixeira Veras1,2, Nádia Skorupa Parachin2,3, João Ricardo Moreira Almeida4,5
1Brazilian Agricultural Research Corporation, EMBRAPA Agroenergia, Parque Estação Biológica, PqEB-W3 Norte Final-s/nº, Brasília, DF, CEP 70.770-901, Brazil.
Background:
Understanding the effects of oxygen levels on yeast xylose metabolism would benefit ethanol production. In this work, xylose fermentative capacity of Scheffersomyces stipitis, Spathaspora passalidarum, Spathaspora arborariae and Candida tenuis was systematically compared under aerobic, oxygen-limited and anaerobic conditions.
Results:
Fermentative performances of the four yeasts were greatly influenced by oxygen availability. S. stipitis and S. passalidarum showed the highest ethanol yields (above 0.44 g g-1) under oxygen limitation. However, S. passalidarum produced 1.5 times more ethanol than S. stipitis under anaerobiosis. While C. tenuis showed the lowest xylose consumption rate and incapacity to produce ethanol, S. arborariae showed an intermediate fermentative performance among the yeasts. NAD(P)H xylose reductase (XR) activity in crude cell extracts correlated with xylose consumption rates and ethanol production.
Conclusions:
Overall, the present work demonstrates that the availability of oxygen influences the production of ethanol by yeasts and indicates that the NADH-dependent XR activity is a limiting step on the xylose metabolism. S. stipitis and S. passalidarum have the greatest potential for ethanol production from xylose. Both yeasts showed similar ethanol yields near theoretical under oxygen-limited condition. Besides that, S. passalidarum showed the best xylose consumption and ethanol production under anaerobiosis.
More Related Videos
07:38Saccharomyces cerevisiae Exponential Growth Kinetics in Batch Culture to Analyze Respiratory and Fermentative Metabolism
Published on: September 30, 2018
06:53In Vivo Monitoring of Transcriptional Activity During Metabolic Transition Using a Bioluminescent Reporter in Yeast
Published on: February 21, 2025
Related Concept Videos
01:23Microbial Fermentation
01:29Fermentation
Fermentation is a type of metabolic process that occurs in the absence of oxygen, where organic molecules such as glucose are broken down to produce energy. During this process, the...