1 Structure of wood in relation to decay. Chemical

Cellulose- b 1-4 Glucose polymer, organized into microfibrils, crystalline & non-crystalline- Broken down via enzymatic digestion at repeating bond structure Endo-cellulase cleave in the middle Exo-cellulases, cellobiohydrolases (CBH), work from the ends of long strands cleaving 2-4 units from the end beta-glucosidases cleave di and tri-saccharides into monomers (i.e., glucose). hemicellulose- short chain polymers: xylans (polymerized pentose sugars), glucomannans (hexose sugars), Primarily: xylose, mannose, galactose, rhamnose, and arabinose, Cross-linked to cellulose and pectins. broken down enzymatically by hemicellulases, but also soluble in alkali and hydrolyzes readily in dilute acid to form sugar acids; Lignin- phenyl propane skeleton: complex non-repeating structure Broken down via free radical reaction.(i.e., the Fenton reaction)