The effective and efficient valorization of polysaccharide-rich feedstocks is undisputedly a key factor in the quest for a more sustainable planet and a biobased economy. Several covalent and non-covalent interactions within the biomacromolecules define the complex, intricate, and rigid structure of lignocellulose and related biomasses. However, none of the current methods to disrupt the complex interactions of feedstocks and enhance their hydrolysis for subsequent valorization are highly selective and efficient enough, hence the need for new methodologies in this respect. Deep eutectic solvents (DES) are special types of ionic liquids, which are cheaper, less toxic, and more biocompatible than other ionic liquids. They have been identified as important green solvents and functional fluids with immense potential for catalytic transformation of polysaccharide-rich biomass into a diverse range of products. The unique properties of DES enable them to effectively dissolve and convert biomass into valuable end products. This review paper sheds light on the application of DES in the deconstruction and fractionation of different feedstocks, particularly in the pretreatment step. In this regard, it covers the recent advancements in the applications of various DES in the valorization of biomass and its major components (i.e., cellulose, xylan, chitin, starch, pectin) with special emphasis on the relationship between the inherent properties of DES and their dissolution potential. Focus is also placed on the toxicity, biocompatibility, and reusability of DES. Finally, this article addresses the current and potential issues in the industrial application of DES, with a special focus on future opportunities.

对富含多糖的原料进行有效和高效的增值无疑是寻求更可持续的地球和生物经济的关键因素。生物大分子内的几种共价和非共价相互作用定义了木质纤维素和相关生物质的复杂、复杂和刚性结构。然而，目前破坏原料复杂相互作用并增强其水解以进行后续增值的方法都没有足够高的选择性和足够的效率，因此在这方面需要新的方法。深共熔溶剂 (DES) 是一种特殊类型的离子液体，与其他离子液体相比，它更便宜、毒性更小且生物相容性更好。它们已被确定为重要的绿色溶剂和功能流体，具有将富含多糖的生物质催化转化为多种产品的巨大潜力。DES 的独特特性使其能够有效地溶解生物质并将其转化为有价值的最终产品。这篇综述文章阐明了 DES 在不同原料的解构和分馏中的应用，特别是在预处理步骤中。在这方面，它涵盖了各种 DES 在生物质及其主要成分（即纤维素、木聚糖、几丁质、淀粉、果胶）价值化中的应用的最新进展，特别强调了 DES 的固有特性与它们的溶解潜力。重点还放在 DES 的毒性、生物相容性和可重用性上。最后，