Laccase as a Tool in Building Advanced Lignin‐Based Materials. Issue 21 (8th September 2021) - Agustin, Melissa B.
Abstract: Lignin is an abundant natural feedstock that offers great potential as a renewable substitute for fossil‐based resources. Its polyaromatic structure and unique properties have attracted significant research efforts. The advantages of an enzymatic over chemical or thermal approach to construct or deconstruct lignins are that it operates in mild conditions, requires less energy, and usually uses non‐toxic chemicals. Laccase is a widely investigated oxidative enzyme that can catalyze the polymerization and depolymerization of lignin. Its dual nature causes a challenge in controlling the overall direction of lignin‐laccase catalysis. In this Review, the factors that affect laccase‐catalyzed lignin polymerization were summarized, evaluated, and compared to identify key features that favor lignin polymerization. In addition, a critical assessment of the conditions that enable production of novel lignin hybrids via laccase‐catalyzed grafting was presented. To assess the industrial relevance of laccase‐assisted lignin valorization, patented applications were surveyed and industrial challenges and opportunities were analyzed. Finally, our perspective in realizing the full potential of laccase in building lignin‐based materials for advanced applications was deduced from analysis of the limitations governing laccase‐assisted lignin polymerization and grafting. Abstract : Laccases as builders : Similar to their role in the formation of lignin in nature, laccases are capable of building advanced lignin‐based materials, given the optimum laboratory conditions. This Review evaluates the factors that affect laccase‐catalyzed lignin polymerization and grafting reactions. Patented applications of lignin‐based materials produced via laccase catalysis are highlighted and potential routes towards unlocking the full capacity of laccase in lignin valorization are proposed.