Innovation could speed up and clean up bioethanol production

Scientists from Imperial College London claim to have developed a solution which could lead to cheaper and more environmentally friendly biofuel production.

According to the researchers, the breakthrough means they can break down plant-based biomass ’30 times faster than currently possible.’

Dr Alex Brogan, of Imperial’s Department of Chemical Engineering, and colleagues modified the glucosidase enzyme which plays a part in breaking down complex carbohydrates in biomass, such as cellulose into glucose. This glucose can be fermented to make bioethanol.

Currently, releasing glucose from cellulose is both the most expensive and time consuming part of bioprocessing. This is partly explained by the fact enzymes typically stop working at temperatures higher than 70 degress Celsius, or when in industrial solvents like ionic liquids.

Brogan and colleague sought to overcome this limitation and produce a more robust enzyme that could work at higher temperatures and in ionic liquids. They altered glucosidase’s chemical structure so it could withstand heat up to 137 degrees, and also be used in ionic liquids.

According to the team’s results, published in the journal Nature Chemistry, they found that the combined effect of heat resistance and solubility in ionic liquids increased the glucose output 30-fold. If the technique is taken up on a large scale, fuel-related carbon emissions could fall by 80-100%, they claim.

Dr Brogan said, in a statement from Imperial College: "We've made bioprocessing faster, which will require less equipment and will reduce carbon footprint. One major advantage of this will be increased biofuel production - potentially helping biofuels become more widespread as a result."