Abstract
Wood is complex in its chemical composition that has an important influence on its chemical behavior and mechanical strength. The complexity is reflected in the ultrastructure of the wood cell wall. In particular, the concentration of main components (cellulose, hemicelluloses and lignin) changes depending on many factors such as the different type or parts of wood, and varies in different cell wall layers. From an ultrastructural standpoint, we describe the current level of knowledge about chemical characteristics of the wood cell walls. The information of distribution of main components in the cell walls of normal wood, reaction wood and water-logged archaeological wood, the cellulose microfibrils orientation, and the interactions between main components were presented based on the use of advanced techniques including transmission electron microscopy, scanning electron microscopy, spectral imaging and nuclear magnetic resonance. In addition, the chemical changes of the wood cell wall during pretreatment are discussed. This mini-review not only provides a better understanding of wood chemistry, but also brings new insights into cell wall recalcitrance.
Highlights
Wood cell wall is a multi-component system, mainly consisting of cellulose, hemicellulose and lignin, which differ from one another in chemical structure and physical properties
In this the chemical characteristics study the distribution of lignin based on the characteristic absorption of lignin and phenols vided by spectra, and the architecture of the wood cell wall is visualized by a microscope
The results showed that cellulose was mostly concentrated in the secondary wall of poplar fibers, whilst the distribution of hemicellulose
Summary
Wood cell wall is a multi-component system, mainly consisting of cellulose, hemicellulose and lignin, which differ from one another in chemical structure and physical properties. The wood contains pectin, starch and proteins and low molecular weight components such as extractives, water-soluble organic compounds as well as inorganic compounds (Table 1) [4]. The content of these components varies in different parts of the same wood, such as earlywood and latewood, bark and xylem [5]. Cellulose microfibrils form the cell wall framework embedded in the matrix of lignin and hemicelluloses, which have protective and structural functions conferring resistance to chemical, microbial or enzymatic deconstruction.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
