FARE Laboratory, INRA, Université de Reims Champagne Ardenne, Reims, France.
Platform of Cellular and Tissular Imaging (PICT), Université de Reims Champagne Ardenne, Reims, France.
Bioresour Technol. 2019 Dec;293:122015. doi: 10.1016/j.biortech.2019.122015. Epub 2019 Aug 16.
Lignocellulose biomass can be transformed into sustainable chemicals, materials and energy but its natural recalcitrance requires the use of pretreatment to enhance subsequent catalytic steps. Dilute acid pretreatment is one of the most common and efficient ones, however its impact has not yet been investigated simultaneously at nano- and cellular-scales. Poplar samples have been pretreated by dilute acid at different controlled severities, then characterized by combined structural and spectral techniques (scanning electron microscopy, confocal microscopy, autofluorescence, fluorescence lifetime, Raman). Results show that pretreatment favours lignin depolymerization until severity of 2.4-2.5 while at severity of 2.7 lignin seems to repolymerize as revealed by broadening of autofluorescence spectrum and strong decrease in fluorescence lifetime. Importantly, both nano-scale and cellular-scale markers can predict hydrolysis yield of pretreated samples, highlighting some connections in the multiscale recalcitrance of lignocellulose.
木质纤维素生物质可以转化为可持续的化学品、材料和能源，但由于其天然的抗降解性，需要使用预处理来增强后续的催化步骤。稀酸预处理是最常见和最有效的方法之一，但它的影响尚未在纳米和细胞尺度上同时进行研究。杨木样品在不同的控制条件下进行了稀酸预处理，然后通过结合结构和光谱技术（扫描电子显微镜、共聚焦显微镜、自发荧光、荧光寿命、拉曼）进行了表征。结果表明，预处理有利于木质素解聚，直到 2.4-2.5 的严重程度，而在 2.7 的严重程度下，木质素似乎会重新聚合，这表现为自发荧光光谱的变宽和荧光寿命的强烈下降。重要的是，纳米尺度和细胞尺度的标记物都可以预测预处理样品的水解产率，这突出了木质纤维素多尺度抗降解性之间的一些联系。
