Topochemical Characterization of Lignins and Phenolic Extractives in Wood Cell Walls
نویسنده
چکیده
The topochemical distribution of lignin and phenolic extractives in woody tissue was determined at a cellular level using scanning UV microspectrophotometry (UMSP). This improved analytical technique enables direct imaging of lignin distribution within individual cell wall layers with a resolution of 0.25 μm. The technique is based on the ultraviolet illumination of semi-thin transverse sections (1μm thickness) of the woody tissue which can be related semiquantitatively to the concentration of lignin within the cell wall. For demonstration, selected softwood (Picea abies), and hardwood (Fagus sylvatica) sections were scanned at a defined wavelength and evaluated with the APAMOS software. This approach allows the distribution pattern of lignin and aromatic compounds within the cell wall to be visualised simultaneously. The method was found to be ideally suited for the study of lignification during wood formation, the detection of phenolic extractives, the removal of lignin during pulp processes, and other applications in chemical technology of wood.
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