Fungal Enzymes in the Production of Biofuels

Abstract

Due to the exhaustion of non-renewable fossil fuel resources, rising costs of petroleum-based fuels, efforts to save energy, and the acceleration of global warming, renewable energy has received attention on a global scale. Biofuels have become a viable alternative energy source to cut greenhouse gas emissions and combat global warming. It’s also been demonstrated to be a means of achieving long-term energy sustainability. There are four generations of biofuels based on feedstocks. Before fermentation, edible feedstocks like as sugarcane juice, cereals, and starch-rich root tubers are hydrolysed with the aid of amylases and inulinases to produce first-generation biofuels. Since they compete with human food, although making up the majority of the biofuel produced at the time, these are being opposed by a variety of organizations. The second-generation biofuels are created to overcome these challenges by utilizing non-edible biomass, such as agricultural waste residues, agro-industrial waste, horticultural wastes, and food wastes rich in cellulose, hemicellulose, pectin, and starch saturated with refractory lignin. The carbohydrates in these feedstocks are hydrolysed enzymatically utilizing cellulases, hemicellulases, pectinases, and amylases after they have been delignified through physio-chemical or biological pretreatments employing ligninases. Third-generation biofuels are created from starch- and cellulose-rich algal biomass using amylase- and cellulase-based hydrolysis. Third-generation biofuels use third-generation hydrolytic enzymes along with genetic engineering and molecular biology to enhance algal strains. Fourth-generation biofuels are an improvement over third-generation biofuels. The environmentally friendly generation of biofuels relies heavily on enzymes. Fungal enzymes are extracellular and exhibit substantially better productivity with simple downstream processes than bacterial enzymes, which are largely intracellular or spore-bound and have low yields. Biotechnological innovations gave rise to strain enhancement, which increased the productivity of certain hydrolytic enzymes and their adaptability to diverse environmental conditions during the conversion of various feedstocks to biofuel. Different generations of biofuels, the enzymes utilized in their production, the significance of each generation, and the potential of biofuels as a source of sustainable energy are all covered in this chapter.