Uganda scientists find ways to get ethanol from stems and leaves

Uganda scientists have made a breakthrough in extracting bio-ethanol from non-food parts of plants of cassava stems, cassava leaves, pineapple leaves, elephant grass stems and wood paving the way for commercial production of ethanol from new source materials. Cellulosic ethanol is difficult and expensive to break down into simple sugars required for ethanol production, but is eventually cheaper say the researchers who argue that the initial investment for biofuels is much lower than for fossil fuels.

The research has proved that it is possible to get high quality ethanol for use in sanitary and automobile fuel that offers investment opportunities. Ethanol is used in the production of pharmaceutical products, food preservation, home-based energy such as small lanterns, locally made lanterns and other lighting equipment. The research aims at producing biofuels that can be blended with fossil fuels to reduce greenhouse gas emissions. The government energy policy also advocates the increased research and use of modern renewable energy sources, which it expects to increase from the current four per cent to 61 per cent of the total energy consumption by 2017. In the policy, the government proposes a law that fossil fuel companies blend petroleum with up to 20 per cent biofuels to be used mainly in the transport sector and power generation.

 Sugar-hungry yeast to boost biofuel production

Engineering yeast to transform sugars more efficiently into alcohols could be an economically and environmentally sound way to replace fossil fuels. Scientists are working out how to modify yeast cells so that they successfully convert a wider range of sugars from plant waste such as wheat and rice straw into alcohol that can be used as biofuel.

Bioalcohols produced by microbial fermentations are an example of second generation biofuels that use raw materials not used in food production. Plant waste is available in large amounts and contains a mixture of complex sugars including hexoses and pentoses that can be fermented to alcohol. As these feedstocks represent the biggest portion of processing costs, we need rapid and efficient conversion of all sugars present but at the moment there is a lack of microbes that will efficiently convert both hexoses and pentoses into ethanol.

Bakers' yeast Saccharomyces cerevisiae is already used in the beverage industry to efficiently convert hexose sugars, such as glucose, into ethanol. By transferring genes from bacteria that naturally break down pentose. The scientists have engineered S. cerevisiae to successfully ferment pentose and hexose sugars as pentoses represent a substantial part of the feedstock, the engineered yeast gives a much higher yield of ethanol for the same amount of feedstock.

Second-generation biofuels from genetically-modified poplar trees.

Europe is making progress in the development of sustainable biofuels, after recently harvested its first crop of genetically-modified poplars. The trees will be used to produce bioethanol. Researchers have developed genetically-modified poplars that produce less lignin, facilitating the bioethanol production process. The first crop of genetically-modified poplars was planted in an open air field trial in Ghent and this crop has now been harvested and will be converted into second-generation bioethanol. In the pilot plant, scientists develop industrial processes to convert agricultural co-products such as wheat straw, corn cobs and wood into so called second-generation biofuels, bioplastics and other biobased products.

The Bio Base Europe Pilot Plant in Ghent, Belgium, is a flexible and diversified pilot plant that operates at ton scale. It is a one-stop-shop that performs the entire value chain in a single plant, from the biomass green resource up to the final product. The Bio Base Europe Pilot Plant operates as an open innovation centre as it is open to companies and research institutions throughout the world looking to develop bio-based products and processes, scale-up and optimise bioprocesses and custom-manufacture bio-based products at ton scale. The centre encourages network activities, technological innovation and entrepreneurship and conducts a public information and communication program.

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