White-Rot Degradation of Lignin and Xenobiotics

摘要: Wood contains three important classes of biopolymers; cellulose, hemicelluloses and lignin. Lignin is a highly irregular, three-dimensional biopolymer composed oxygenated phenylpropane units. It synthesised by plants mainly to provide strength protection. formed via peroxidase-catalyzed polymerisation methoxysubstituted ρ-hydroxy-cinnamyl alcohols. The initially phenoxy-radicals randomly combine form variety bonds which the β-O-4 interunit linkage most prevalent. Other representative include β-5 (phenylcoumaran), 5,5 (biphenyl), α-O-4 (α-arylether) β-1 (diarylpropane); α β refer to, respectively, Cα Cβ carbon atoms units, O-4 indicates oxygen atom ρ-hydroxy-group. numbers in aromatic ring, with C-1 carrying propyl side chain. A schematic representation lignin structure given Dart et al. Chapter 7, this volume. benzylic hydroxy groups are introduced quinone methide intermediates (Higuchi 1990).