Heterogeneity and rigidity of lignocellulose causing resistance to its deconstruction have provided technical and economic challenges in the current biomass conversion processes. Lignin has been considered as a crucial recalcitrance component in biomass utilization. An in-depth understanding of lignin properties and their influences on biomass conversion can provide clues to improve biomass utilization. Also, utilization of lignin can significantly increase the economic viability of biorefinery. Recent lignin-targeting pretreatments have aimed not only to overcome recalcitrance for biomass conversion but also to selectively fractionate lignin for lignin valorization. Numerous studies have been conducted in biomass characteristics and conversion technologies, and the role of lignin is critical for lignin valorization and biomass pretreatment development. This review provides a comprehensive review of lignin-related biomass characteristics, the impact of lignin on the biological conversion of biomass, and recent lignin-targeting pretreatment strategies. The desired lignin properties in biorefinery and future pretreatment directions are also discussed.

中文翻译：

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木质素在木质纤维素生物质转化中的关键作用和最近的预处理策略：全面综述。

木质纤维素的异质性和刚性导致对其解构的抵抗力，在当前的生物质转化过程中提供了技术和经济挑战。木质素已被认为是生物质利用中至关重要的顽固成分。对木质素特性及其对生物质转化的影响的深入了解可以为提高生物质利用率提供线索。而且，木质素的利用可以显着提高生物精炼厂的经济可行性。最近的靶向木质素的预处理不仅旨在克服生物质转化的顽固性，而且旨在选择性地分离木质素以进行木质素增值。在生物质特征和转化技术方面进行了大量研究，木质素的作用对于木质素的增值和生物质预处理的发展至关重要。这篇综述提供了木质素相关生物量特性的全面综述，木质素对生物量生物转化的影响以及最近针对木质素的预处理策略。还讨论了生物精炼厂中所需的木质素特性和未来的预处理方向。