Press release: http://news.aces.illinois.edu/news/u-i-scientists-develop-green-pretreatment-miscanthus-biofuels

Journal article (full access may require paid subscription): http://pubs.rsc.org/en/Content/ArticleLanding/2013/GC/C3GC37099B

University of Illinois scientists have demonstrated an environmental and economical way of pretreating biomass from the grass Miscanthus for biofuel production with the use of a switchable and recoverable solvent.

Conventional pretreatment process of lignocellulosic biomass, such as grass and wood, uses high temperature and harsh chemical conditions to deconstruct the complex lignocellulose before they can be fermented into ethanol. The current study by University of Illinois researchers used the solvent called butadiene sulfone for pretreatment. Butadiene sulfone can switch chemically to another form at relatively lower temperature, forming an acid in the presence of water that can break down complex sugars in pretreated Miscanthus biomass. Aside from its unique switching ability, butadiene sulfone can reform from its derivatives after decomposition, allowing recovery for potential re-use in pretreatment process.

The researchers found that the acid product could break down up to 91 percent of the complex xylan sugars and butadiene sulfone could degrade about 58 percent of the tough lignin polymer that impedes ethanol production while preserving 90 to 99 percent of cellulose. The findings were published in the journal Green Chemistry.

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News article: http://www.sciencedaily.com/releases/2013/05/130519191104.htm

Scientists at the University of California, Davis used the principle of synthetic biology to engineer a strain of photosynthetic cyanobacterium so that it could grow even without light.

In a report presented at the 113th General Meeting of the American Society for Microbiology, the UC Davis researchers described how they rewired the metabolism of the cynobacterium Synechococcus elongatus strain PCC 7942, a model organism that relies on carbon dioxide and light energy for growth. This cyanobacterium was previously engineered to recycle carbon dioxide into a variety of biofuels and valuable chemicals in the presence of light, which is a limiting factor in biofuel conversion. To overcome this constraint, foreign genes were inserted into the cyanobacterium to enable it to grow and generate biofuels in diurnal (light or dark) conditions.

The scientists said that advances in this kind of research is desirable for more efficient, economical and controllable bioproduction systems.

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News release: http://newscenter.lbl.gov/science-shorts/2013/05/15/turning-up-the-heat-on-biofuels/

Researchers at the Energy Biosciences Institute (EBI) have engineered an enzyme from a fungus that degrades lignocellulose biomass for biofuel production (e.g., grass and wood) so that the enzyme remains stable and active at a higher temperature range.

The EBI researchers used the strategy called "B factor guided mutagenesis" to enhance the thermal stability of an endoglucanase enzyme from the fungus Trichoderma reesei. The native form of this enzyme is not stable at temperatures above 50 degrees Celsius. Under thermal stress, the amino acids in the enzyme easily fall out of place just like loose knots in a rope. Researchers use the B factor value to measure the amino acid's ability to loosen. The researchers sought to tighten up some portions of the enzyme by mutating the amino acids and decreasing the B factor values. 

The engineered enzyme was up to twice as active on target substrates as the native enzymes at temperatures ranging from 50 to 65 degrees Celsius. When expressed in model fungus Neurospora crassa, it was able to degrade lignocellulose at 60 degrees Celsius as efficiently as the native enzyme at 50 degrees Celsius.

Enzymatic degradation of lignocellulose at high temperatures offers several potential advantages, including higher solid loadings due to reduced viscosity, lower risk of microbial contamination, greater compatibility with high temperature pretreatments, enhanced mass transfer and faster rates of hydrolysis.

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News article: http://www.ballinaadvocate.com.au/news/process-turns-timber-waste-into-diesel/1877201/

In Australia, researchers at the Southern Cross University's Forestry Department are planning to pilot small scale plants that would harness local biomass resource and convert them into biofuel.

The Northern Rivers area produces plenty of cellulose biomass but production tends to be localized in small isolated pockets. Collecting the biomass and transporting them to a central facility would impact the economic viability of biomass processing. The planned pilot project will develop localized small scale versions of the Fischer-Tropsch process used in Germany during the World War II to turn coal into liquid fuel. The university research team has developed a gasifier that turns wood chips into gas, which can be further synthesized, using the Fischer-Tropsch process, to recombine hydrogen and carbon monoxide into liquid hydrocarbons. The resulting bio-crude can be refined to create diesel fuel.

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News article: http://www.biofuelsjournal.com/articles/University_of_Alicante__Spain__Researchers_Develop_Photobioreactor_to_Produce_Biofuel_From_Algae-132745.html

In Spain, University of Alicante researchers have patented a new device, consisting of a photobioreactor, that allows more efficient cultivation of microalgae as raw material for biofuel and other high-value products.

The prototype designed by the Research Group in Polymer Processing and Pyrolysis allows mass production, less cleaning and maintenance operation, better use of carbon dioxide, better light transfer and it is easily scalable for larger production. According to the research group, the unique design of this new device addresses the difficulties in microalgae cultivation for biofuel and industrial substances, citing the high cost of production that hinders commercial viability.

Apart from biomass for biofuel production, microalgae provide raw materials that can be used to produce substances of high value in food, pharmaceutical and cosmetic sectors. Depending on the species, products such as antibiotics, polyunsaturated fatty acids, enzymes, proteins, vitamins, triglycerides or antioxidants, can be derived from microalgae.