Laccase-Mediated Valorization of Lignocellulosic Biomass: An Eco-friendly Approach Towards the Sustainable Environment

Lignocellulosic biomass is one of the excessive materials present on this planet that can be converted into several important end products such as enzymes, organic acids, chemicals, and feed. It can also be used as a renewable source of bioenergy with the potential to reduce dependence on non-renewable resources. Several processes are developed for the effective valorization of this biomass, including physical, thermochemical, and biological. However, every process has its own set of limitations where the biological method employing enzymes is considered to be an environment friendly and sustainable, converting this biomass into value-added products, and hence, it may become an economical method. The inherent recalcitrant structure of lignocellulosic biomass is often challenging to enzymatic hydrolysis as cellulose microfibrils and hemicellulose matrix are intimately linked with lignin. Hence, lignin being a primary component of biomass, the majority of pretreatment procedures are designed to target lignin where laccase originating from microorganisms is considered an efficient option to alter the shape of lignin and allow other hydrolytic enzymes to reach cellulose and hemicellulose. This review compiles the recent developments on the application of microbial laccases for lignocellulosic biomass valorization along with challenges and future directions.