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Biofuels Breaking Down Stubborn Cellulose

The biochemical conversion of biomass into liquid fuel yields bio-fuels

Biofuels Breaking Down Stubborn Cellulose

What are biofuels?

The biochemical conversion of biomass into liquid fuel yields bio-fuels. Today, Biofuels are generating a lot more interest and attention. This is due to the relevance of concepts of sustainability and recycling. Biomass can be anything organic, ranging from dead plants or agricultural refuse to animal excrement and kitchen waste. The ready availability of raw materials is what makes biofuels such an exciting field to work in. Along with all the advantages encouraging bio-fuels, it does come with hurdles of its own. The science is still relatively new and the setup required for extraction is expensive or experimental.

The two most common types of biofuels are ethanol and biodiesel. Today, ethanol is made by fermenting any biomass high in carbohydrates through a process similar to beer brewing. However, scientists are now developing technology to allow it to be made from cellulose and hemicelluloses. Cellulose and hemicelluloses are the fibrous matter that makes up the bulk of plant matter.

The problem of using cellulose to make biofuel is that it is not water soluble. This makes it hard to process. Typically biorefineries use a mix of enzymes and water molecules to break down plant matter. Recently, oxidative enzymes, lytic polysaccharide monooxygenases (LPMOs,) have been discovered that use oxygen to break down cellulose more efficiently. However, the working of these enzymes is not known, until Graz University of Technology Scientists got to work on it.

Through the use of atomic force microscopy, researchers were able to observe the enzyme activity on the surface of cellulose. This enabled them to understand the proceedings of the cellulose breakdown and provide proof for the working of the enzymes. For the hydrolytically active enzyme, it was observed that the enzyme gets adsorbed on the surface of cellulose, moves along the chain step by step, and cleaves off small parts of the cellulose chain. When LPMOs were added to the mix of enzymes, researchers observed that LPMOs generated more binding sites on the surface for the hydrolytically active enzyme which increased the enzyme dynamics on the surface.

This study has enabled a better understanding of these processes. This will, in turn, influence the conversion processes for biofuels and make them more efficient. Topics like these are becoming more relevant and important as the world shifts from its dependence on fossil fuels. Let us hope biofuels provide that alternative that can replace fossil fuels.