Seaweed biofuel farms have come a step closer to reality with an improvement in the way seaweed sugars can be converted to ethanol.
Dried seaweed can be fermented to produce ethanol but breaking down galactose, the dominant sugar in seaweed, is a slow process.
Now, researchers have modified the expression of three genes of the yeast Saccharomyces cerevisiae, which is used in the fermentation process to break down sugars to ethanol. The improved strain creates more enzymes, leading to a 250 per cent increase in the rate of galactose sugar fermentation compared with a control strain, according to a paper in the current issue of Biotechnology and Biongineering (March).
Yong-Su Jin, one of the study's authors, and a researcher at the University of Illinois at Urbana-Champaign, United States, told SciDev.Net that his group will now explore the feasibility of harvesting and fermenting seaweed on large scales, which may involve cultivating plants along arrays of floats to ensure they receive enough sunlight.
Seaweed can produce biofuels in a more environmentally sustainable way than land-based crops, as it does not require fresh water or fertilisers, and it could potentially provide income for people in the small island nations of South-East Asia.