Agricultural Waste Could Be Used as Biofuel

(Phys.Org) Straw-powered cars could be a thing of the future thanks to new research from the University of East Anglia (UEA).

A new study pinpoints five strains of yeast capable of turning agricultural by-products, such as straw, sawdust and corncobs, into bioethanol - a well-known alcohol-based biofuel.

It is estimated that more than 400 billion litres of bioethanol could be produced each year from crop wastage.

One way to avoid these problems is to use genetically modified yeasts, but this new research has found five strains of naturally occurring yeasts which could be used successfully in the fermentation process.

"Bioethanol is a very attractive biofuel to the automotive industry as it mixes well with petrol and can be used in lower concentration blends in vehicles with no modifications. In Brazil, vehicles which run purely on bioethanol have been on the roads since 1979.

"Breaking down agricultural waste has previously been difficult because many strains of yeast necessary for fermentation are inhibited by compounds in the straw. Their toxic effects lead to reduced ethanol production."

The research team investigated more than 70 strains of yeast to find the most tolerant. They found five strains which were resistant to the toxic compound furfural, and which produced the highest ethanol yield.

Of the five furfural tolerant strains S. cerevisiae NCYC 3451 displayed the greatest furfural resistance. The genomic lineage of this strain links it to yeast used in the production of the Japanese rice wine Sake.

The research was carried out in collaboration with the Institute of Food Research (IFR) and the National Collection of Yeast Cultures, which is based at the IFR. It was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Department for Environment, Food & Rural Affairs (Defra).

'Identification of furfural resistant strains of Saccharomyces cerevisiae and Saccharomyces paradoxus from a collection of environmental and industrial isolates' is published in the journal Biotechnology for Biofuels. READ MORE and MORE (Science Times) ( Abstract (Biotechnology for Biofuels)