Fuel from Ag Waste

Converting cellulose-rich agricultural waste into fuel is a challenge that has eluded researchers for years. In order to produce biofuel, the waste needs to be fermented – and that requires yeast. But before that can even occur, it needs to be turned into a substance that can be fermented. That process requires heat and acidic conditions, and produces compounds known as furfurals, which are toxic to yeasts. Certain genetically modified yeasts have been developed that are tolerant to furfurals, but U.K. researchers have now identified some naturally-occurring strains that can withstand these compounds.

The best of the bunch turns out to be related to the yeast that’s used to ferment rice into Sake. Called S. cerevisiae NCYC3451, it produced the highest ethanol yield of the five strains studied. New processes such as these would relieve pressure on farmers by providing a useful and economical means to dispose of agricultural waste. More importantly, however, the ability to generate fuel from straw, corncobs, and sawdust would alleviate the need to choose between using land used for “food crops” and using land for “fuel crops.”