Raman Microprobe Evidence for Lignin Orientation in the Cell Walls of Native Woody Tissue

Abstract
Raman microprobe spectra from the secondary wall of earlywood tissue from Picea mariana (black spruce) reveal evidence of the orientation of lignin relative to the plane of the cell wall. In most instances, the aromatic rings of the phenyl propane structural units are parallel to the plane of the cell-wall surface.