Using the tools of metagenomics and metaproteomics, a team of scientists led by the US Department of Energy's Joint BioEnergy Institute (JBEI) has identified bacterial species whose enzymes are actively involved in the deconstruction of switchgrass biomass at high temperature.

The research group reported in the journal Plos One a study on switchgrass-associated consortium of thermophilic bacteria, microbes that thrive at extremely high temperatures and are believed to be a rich source of biomass-degrading enzymes. The study aimed to analyze the functional roles of individual members of the compost-derived microbial consortium in the breakdown of lignocellulosic biomass into sugars that can be fermented into biofuels.

The researchers determined the metabolic capabilities of the consortium members through analysis of metagenomic sequences. Then they used metaproteomic measurements to identify the enzymes, predicted by metagenomic analysis, that were actually produced by the microbial community. The team found out that the most abundant strains in the consortium contributed fewer enzymes for biomass deconstruction.

Analysis of the switchgrass deconstruction proteome confirmed the importance of Gemmatimonadetes and Paenibacillus strains and indicated the presence of unexplored bacterial proteins with important roles in lignocellulose deconstruction.

The large-scale planting of Jatropha curcas in hot, dry coastal areas around the world could help reduce atmospheric levels of carbon dioxide, according to a study published in the journal Earth System Dynamics by a multi-disciplinary team of German researchers.

Using computer models and data from plantations in Egypt, India, and Madagascar, the team calculated that widespread cultivation of the resilient Jatropha, which can also be used in biofuel production, could capture 17 to 25 tons of carbon dioxide per hectare from the atmosphere annually. A plantation occupying only 3 percent of the Arabian Desert, for example, could absorb in a period of 20 years all the carbon dioxide produced by motor vehicles in Germany over the same period.

According to the researchers, this so-called carbon farming approach is very suitable for Jatropha because of its ability to grow in hot, dry regions which are unsuitable for food crops. With about one billion hectares suitable for carbon farming, the method has the potential to sequester a significant portion of the earth warming carbon dioxide dumped into the atmosphere since the industrial revolution.

In terms of cost, carbon farming was found to be competitive compared to the carbon capture and storage (CCS) technique. Desalination and irrigation requirements after few years of implementation can be supported by bioenergy produced by the plants (in the form of tree trimmings). Harvesting the Jatropha fruits for biofuel production would reduce the amount of carbon sequestered by the plantation as a whole but would be worthwhile in order to provide local employment and as an additional source of income for the plantation owners.

Researchers at the UK-based Institute of Food Research (IFR) have successfully produced high concentration of ethanol from waste paper for the first time, matching the yields obtained from traditional food-based sources.

Ethanol conversion normally involves the breakdown of carbohydrates to simple sugars, called saccharification, and the use of microbial fermentation to turn the sugars into ethanol. The IFR scientists optimized the process known as semi simultaneous saccharification and fermentations (SSSF) with batch additions of shredded waste paper as the substrate.

The success of the strategy relied on a specialized bioreactor that is able to mix and digest the raw material when fed in batches into the machine. Early addition of enzymes followed by batch addition of paper substrate resulted in ethanol production at a concentration of up to 11.6 percent which matched the yields obtained from first generation biofuel feedstocks such as sugarcane, corn and wheat.

These initial findings are expected to be scaled up further to demonstrate the economic viability of the process, which has a great potential for sustainable biofuel production, considering the fact that over 12 million tons of paper waste is generated annually in the UK alone.

In the USA, the Department of Energy has announced $16.5 million in grants to four projects in California, Hawaii and New Mexico aimed at breaking down technical barriers and accelerating the development of sustainable, affordable algae biofuels.

The grants were awarded to the following: Hawaii Bioenergy ($5 million), Sapphire Energy ($5 million), New Mexico State University ($5 million) and California Polytechnic State University ($1.5 million).

The projects include developing a cost-effective photosynthetic open pond system to produce algal oil, developing a new process to produce algae-based fuel that is compatible with existing refineries, and increasing the yield and productivity of microalgae.

In addition, the DOE has announced $6 million to support a project aimed at reducing harvesting, handling and pre-processing costs across the entire biomass feedstock supply chain.