MOLECULAR BIOTECHNOLOGY TO IMPROVE BIOFUEL PRODUCTION FROM BIOMASS

Biotechnology strategies are continuously in development, with the aim to optimize biofuel production from microorganisms present in biomass. Organic waste is mostly made of vegetal tissue, with dominant contribution of lignocellulosic polymers. Microbial consortia of bacteria and enzymes have a strategic role in depolymerisation and biodegradation. To improve the biogas production, one modern concept in biotechnology is to increase the quality of the microbial organisms in term of higher yield and efficiency. Examples of this strategy are genetically modified microorganisms that can better disassembly the polymers, e. g. C. thermocellum strain, and S. cerevisiae strain MEL2. A second concept is the manipulation of transcriptional and enzymatic pathways with genetic engineering tools to improve raw materials quality and, consequently, increase the entire process yield. A remarkable case is represented by bioethanol production. Studying metabolic pathways that plants use to create complex resistant substances helps to find methods to reduce the molecular crystallinity degree and make monomers easily available for microorganisms. Biodiesel production from triacylglycerols of vegetal biomass is another significant application of molecular biotechnology. It is crucial to understand where and how plants collect the triacylglycerols for possible modifications. This contribution presents some strategies in biotechnology to improve biofuels production from biomass. Understanding composition, localisation and metabolism of the complex substrates allows selecting biotechnology modifications and molecular tools.