Unveiling the Biomass Valorization: The Microbial Diversity in Promoting a Sustainable Socio-economy

Lignocellulosic biomass is of significant industrial and scientific interest. Residues derived from different activities (agro-industrial work, food consumption, wood use, urban solid waste, etc.) and their subsequent use are key to extending circularity models to the different technological sectors that are beginning to implement circular economy cycles. Biorefineries are integrated platforms that value waste conversion into various value-added products. The generation of bioproducts derived from lignocellulosic waste (green fuels, green chemicals, and biomaterials) has promoted a shift from a fossil fuel–based economy to a more sustainable one. In addition, integrating biorefineries into the circular economy framework promotes a comprehensive approach to resource management, waste reduction, and sustainable development, which contributes to the overall resilience and efficiency of societal systems. There has been increased focus on the application of “canonical microorganisms” for residual biomass conversion, such as fungi, bacteria, and yeast. However, there is a plethora of other potential microorganisms that can be candidates for new biotechnological applications. This review aims to describe the valorization of different sources of lignocellulosic biomass in the global context, with a focus on Brazilian practice, and to emphasize how the use of microbial diversity is critical to enhancing current technologies, such as advanced liquid fuels. Finally, there is a discussion of the potential of anaerobic fungi, archaea, protists, and oomycetes as microbial product conversion technologies.