Seaweed could be a valuable biofuel feedstock for small countries

Most biofuel comes from feedstock grown on land, such as food crops such as corn or non-food crops like switchgrass. This uses up a lot of agricultural land, but for smaller countries without this land there is value in pursuing seaweed as a feedstock for biofuel production.

Assistant Professor of Microbial Genetics Yong-Su Jin of the Institute of Genomic Biology said that developing ways to use seaweed would be of value to countries with less farmland and more coastline.

“Countries, like Japan and Korea, do not have enough land to produce corn like America can. (Using seaweed as biofuel) can help these smaller countries become less dependent on resources like oil. Seaweed is ideal to use as biofuel because the amount of seaweed and other biomass in oceans is very vast. Even though there are still some problems and concerns, it has huge potential.”

Jin’s team has been researching the potential of seaweed as a biofuel feedstock since 2007. His team has found that a sugar known as galactose (rather than glucose which is produced from most other feedstocks) can be produced from seaweed. The problem with this is that galactose is more difficult to convert into ethanol than glucose. Much of his team’s work has involved trying to modify yeast to produce ethanol from galactose more efficiently. This is difficult; the reason that galactose is harder for microbes to use than glucose is (without getting into the technical detail) because of the chemical properties of galactose; there is not a way that will make galactose easier to convert than glucose.

However, Jin’s research group has made progress in identifying three genes in yeast that ferment galactose into ethanol and have managed to engineer strains of yeast that produce the fuel more efficiently. He says that his research has proven the principle. At the lab scale he has used pure sugars rather than sugars produced from biomass to make ethanol, but commercialization of the technology might prove to be difficult.

His concerns are around the technical challenges of harvesting the seaweed. There would be problems with seaweed farms in the event of storms or rough seas. Ideally these farms would be in areas where the sea is calm. There is also the effect that this might have on the ecosystem; as part of the natural food chain seaweed would have an effect on fish populations in areas where seaweed was harvested.

While he says that the technology needs more work before it is ready to be commercialized (for example, he stresses the need to test the process with biomass-derived galactose), Jin is seeing interest from a number of large Japanese and Korean companies such as Samsung.