A Review: Depolymerization of Lignin to Generate High-Value Bio-Products: Opportunities, Challenges, and Prospects

• Published in: Frontiers in energy research Vol. 9
• Main Authors: Zhou, Ningning, Thilakarathna, W. P. D. Wass, He, Quan Sophia, Rupasinghe, H. P. Vasantha
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 11-01-2022
• Subjects: depolymerization; ferulic acid; lignin; lignin-first biorefining; syringaldehyde; vanillin
• ISSN: 2296-598X; 2296-598X
• DOI: 10.3389/fenrg.2021.758744

Lignin is identified as a promising candidate in renewable energy and bioproduct manufacturing due to its high abundance, polymeric structure, and biochemical properties of monomers. Thus, emerging opportunities exist in generating high-value small molecules from lignin through depolymerization. This review aims at providing an overview of the major technologies of lignin depolymerization. The feasibility of large-scale implementation of these technologies, including thermal, biological, and chemical depolymerizations, are discussed in relation to potential industrial applications. Lignin as a renewable alternative to petroleum-based chemicals has been well documented. This review attempts to emphasize potential applications of lignin-derived monomers and their derivatives as bioactives in food, natural health product, and pharmaceutical sectors. The critical review of the prospects and challenges of lignin-derived bioproducts reveals that the advancement of research and development is required to explore the applications of depolymerization of lignins to their full potential.