Energy: bioethanol production from agricultural waste

With the introduction of a single bacterial gene into yeast, researchers from Department of Biotechnology achieved three improvements in bioethanol production from agricultural waste material: ‘More ethanol, less acetate and elimination of the major by-product glycerol’

Car fuel

Bioethanol is made by the yeast Saccharomyces cerevisiae from sugars obtained from plant biomass. The production of bioethanol is rapidly increasing due to the growing use of bioethanol as a car fuel.

Bioethanol should of course preferably be produced from resources that do not compete with food production. For this reason, efforts are made to produce second-generation bioethanol, using agricultural residues.

Yeast genes

However, during the process byproducts, like acetate, are formed that slow down or halt the bioethanol production. Researchers from the group of Industrial Microbiology (Department of Biotechnology) have now solved these issues. Yeast can, at least in theory, also convert the harmful acetate to ethanol. As it turns out, just one single gene is missing in the yeast. By introducing a single gene from the bacterium Escherichia coli, researchers enabled this conversion of acetate to ethanol by yeast.