Could Plants Be the Key to Better Biofuels?  

Plants play a crucial role in keeping the planet healthy and now, they could be the answer to creating better biofuels. At the University of Massachusetts and the University of California two teams of researchers have uncovered a revolutionary new breakthrough that involves breeding plants with differing amounts of cellulose, hemicellulose or lignin. The idea is to change the composition of cell walls in order to enhance the efficiency of biofuel production.  

Solving the gene puzzle

Researchers focussed primarily on xylem, a plant tissue found in the roots of the Arabidopsis plant. Together the groups pinpointed the gene regulatory networks that support the synthesis of secondary cell wall components. The ability to control the composition of cellulose, hemicellulose and lignin is of immense interest to biofuel researchers. This is because the structures make up the majority of plant matter which is then broken down into biofuel.

Overcoming the lignin issue

While all three cell wall components can be used to create biofuel, lignin is the most problematic. It restricts the extraction of cellulose and hemicellulose which makes the biofuel production process significantly less efficient. Unfortunately, lignin can’t be eliminated from secondary cell walls as the presence of its rigid polymer supports the plant’s ability to waterproof, stabilise and protect itself. Siobhan Brady, co-author of the study and assistant professor in the Department of Plant Biology and Genome Center at UC Davis calls it a “Catch-22.”

So what’s the solution? Brady maintains that instead of eliminating it altogether, "Biofuel researchers would like to breed plants with differing amounts of cellulose, hemicellulose or lignin. Ideally, with less lignin." It’s a revolutionary idea that has never been attempted before. To do this researchers analysed hundreds of transcription factors occurring within the root xylem's regulatory network. Armed with state-of-the-art computer modelling equipment they successfully enhanced the production of individual cell wall components by modifying different transcription factors. All up the researchers identified over 240 undiscovered genes and more than 600 protein/DNA reactions.

Bespoke biofuels

Samuel Hazen, a plant geneticist at UMass Amherst and a co-author of the study explains that the ability to independently manipulate the production of different components represents an enormous leap forward for the biofuel production industry. "This gives us a way to really tweak the system to the way we want," she says. While Arabidopsis is a small weed that won’t be used for large scale biofuel production researchers are already planning on experimenting with different organisms such as sorghum and switch grass. For Hazen, it is "absolutely realistic" that the results will foster the creation of better biofuel.

The search for fossil fuel alternatives has led to the development of energy from a myriad of sources. As well as plants, ‘The Cutting Edge Advances in Worldwide Biodiesel Testing Specifications and Standardisation’ looks at how renewable feedstock such as fats and oils can be used to generate biodiesel.