Probing and visualizing the heterogeneity of fiber cell wall deconstruction in sugar maple (Acer saccharum) during liquid hot water pretreatment

摘要: Liquid hot water (LHW) pretreatment is an effective method to improve enzymatic digestibility of lignocellulosic feedstock by removing hemicellulose/lignin. To better understand how LHW reduces plant cell wall recalcitrance, we applied a combined approach using multiple microscopic techniques and chemometric methods monitor microstructural topochemical changes in the fiber sugar maple (Acer saccharum). The heterogeneity deconstruction various layers was easily visualized based on chemical characterizations through confocal Raman microscopy, combining with principal component analysis cluster analysis. Interestingly, after pretreatment, S2 layer differentiated into two regions, namely heavy-damaged region (outer thin inner S2) more polysaccharides removed, light-damaged (middle which still remained relatively intact. Our results have established direct correlation between following pretreatment. removal (mainly hemicelluloses) rather than lignin played critical role visible damage wall, like cavities, gaps collapses.