Hemicelluloses are a vast group of complex, non-cellulosic heteropolysaccharides that are classified according to the principal monosaccharides present in its structure. Xylan is the most abundant hemicellulose found in lignocellulosic biomass. In the current trend of a more effective utilization of lignocellulosic biomass and developments of environmentally friendly industrial processes, increasing research activities have been directed to a practical application of the xylan component of plants and plant residues as biopolymer resources. A variety of enzymes, including main- and side-chain acting enzymes, are responsible for xylan breakdown. Xylanase is a main-chain enzyme that randomly cleaves the β-1,4 linkages between the xylopyranosyl residues in xylan backbone. This enzyme presents varying folds, mechanisms of action, substrate specificities, hydrolytic activities, and physicochemical characteristics. This review pays particular attention to different aspects of the mechanisms of action of xylan-degrading enzymes and their contribution to improve the production of bioproducts from plant biomass. Furthermore, the influence of phenolic compounds on xylanase activity is also discussed.

中文翻译：

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对木聚糖酶解机理的见解。

半纤维素是一大类复杂的非纤维素杂多糖，根据其结构中存在的主要单糖进行分类。木聚糖是木质纤维素生物质中发现的最丰富的半纤维素。在更有效地利用木质纤维素生物质和发展环境友好的工业过程的当前趋势中，越来越多的研究活动针对植物的木聚糖成分和植物残渣作为生物聚合物资源的实际应用。各种酶，包括主链和侧链作用酶，负责木聚糖分解。木聚糖酶是一种主链酶，可随机切割木聚糖主链中木吡喃糖基残基之间的β-1,4键。这种酶具有不同的折叠，作用机理，底物特异性，水解活性和理化特性。这篇评论特别关注木聚糖降解酶作用机理的不同方面，以及它们对改善植物生物量生产生物产品的贡献。此外，还讨论了酚类化合物对木聚糖酶活性的影响。