Enzymatic hydrolysis of biomass from wood.
Enzymatic hydrolysis of biomass from wood.
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DOI：
10.1111/1751-7915.12346
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发表时间：
2016-03
影响因子：
5.7
通讯作者：
Díez B
中科院分区：
文献类型：
--
作者：
Álvarez C;Reyes-Sosa FM;Díez B
目前纤维素乙醇生产的研究和开发主要集中在农业残留物和专用能源作物，如玉米秸秆和柳枝稷；然而，木质生物质仍然是乙醇生产的重要原料。木材中半纤维素的精确组成强烈依赖于植物种类，因此根据半纤维素的复杂性和预处理类型需要不同类型的酶。一般来说，硬木物种对酶的抗性比软木低得多。对于硬木，木聚糖酶、β‐木糖苷酶和木糖葡聚糖酶是参与半纤维素骨架降解的主要半纤维素酶，而对于软木，甘露聚糖酶和β‐甘露糖苷酶的作用更为相关。此外，有不同的关键辅助酶参与去除半纤维素部分和增加纤维素酶对纤维素纤维的接近性，改善水解过程。已经测试了多种酶混合物，使用从低密度到高密度的生物质（2-20%总固体），并获得了广泛的结果。最近在硬木和软木上开发的商业鸡尾酒的性能将使木材燃料乙醇的商业化迈出进一步的一步。
Current research and development in cellulosic ethanol production has been focused mainly on agricultural residues and dedicated energy crops such as corn stover and switchgrass; however, woody biomass remains a very important feedstock for ethanol production. The precise composition of hemicellulose in the wood is strongly dependent on the plant species, therefore different types of enzymes are needed based on hemicellulose complexity and type of pretreatment. In general, hardwood species have much lower recalcitrance to enzymes than softwood. For hardwood, xylanases, beta‐xylosidases and xyloglucanases are the main hemicellulases involved in degradation of the hemicellulose backbone, while for softwood the effect of mannanases and beta‐mannosidases is more relevant. Furthermore, there are different key accessory enzymes involved in removing the hemicellulosic fraction and increasing accessibility of cellulases to the cellulose fibres improving the hydrolysis process. A diversity of enzymatic cocktails has been tested using from low to high densities of biomass (2–20% total solids) and a broad range of results has been obtained. The performance of recently developed commercial cocktails on hardwoods and softwoods will enable a further step for the commercialization of fuel ethanol from wood.