Application of scanning UV microspectrophotometry to localise lignins and phenolic extractives in plant cell walls

The localisation of lignin and phenolic extractives in woody tissue was determined using scanning UV microspectrophotometry. This improved cellular analytical technique enabled direct imaging of the topochemical lignin distribution within individual cell wall layers with a resolution of 0.25 mum(2). Selected softwood (Picea abies), hardwood (Fagus sylvatica, Entandrophragma cylindricum, Prunus serotina) and monocotyledon (Phyllostachys edulis) sections of 1 mum thickness were scanned at a fixed wavelength and evaluated with the APAMOS software. This approach allowed the distribution pattern of lignins and aromatic extractives within the cell wait to be visualised simultaneously. The method was found to be ideally suited to the study of their subcellular distribution in plant cell walls.