Relationship between production of hydroxyl radicals and degradation of wood, crystalline cellulose, and a lignin-related compound or accumulation of oxalic acid in cultures of brown-rot fungi

• Published in: Journal of wood science Vol. 51; no. 3; pp. 262 - 269
• Main Authors: Kaneko, S.(Kinki Univ., Higashiosaka, Osaka (Japan). Faculty of Agriculture), Yoshitake, K, Itakura, S, Tanaka, H, Enoki, A
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer Nature B.V 01-06-2005
• Subjects: Accumulation; ACIDE OXALIQUE; ACIDO OXALICO; CARIE DU BOIS; CELLULOLYTIC MICROORGANISMS; Cellulose; Crystal structure; Crystalline cellulose; Crystallinity; Degradation; FAGUS CRENATA; Filter paper; FREE RADICALS; Fungi; GLOEOPHYLLUM; Hydroxyl radicals; LAETIPORUS; Lignin; MICRO-ORGANISME CELLULOLYTIQUE; MICROORGANISMOS CELULOLITICOS; OXALIC ACID; Polysaccharides; PUDRICION DE LA MADERA; RADICAL LIBRE; RADICALES LIBRES; Substrates; Substructures; TYROMYCES PALUSTRIS; WOOD DECAY
• ISSN: 1435-0211; 1611-4663
• DOI: 10.1007/s10086-004-0641-3

The degradation of wood, filter paper cellulose, and a lignin-substructure model, was measured in cultures of seven fungi usually regarded as brown-rot fungi. Hydroxyl radical production and the accumulation of oxalic acid in the cultures were also measured. Four of the fungi, Gloeophyllum trabeum, Tyromyces palustris, Laetiporus sulphureus, and Postia placenta, were typical brown-rot fungi, in that they preferentially degraded and eliminated the polysaccharides in wood and produced large amounts of hydroxyl radical. The rates of hydroxyl radical generation in cultures of the four fungi were directly proportional to the degradation rates of wood, cellulose, and the lignin-related compound, and inversely proportional to the amount of oxalic acid in the cultures. Two of the fungi, Daedalea dickinsii and Lentinus lepideus, did not degrade any of the substrates significantly and produced very little hydroxyl radical. Coniophora puteana had the highest rate of cellulose degradation, but did not degrade wood or the lignin model significantly and produced only negligible amounts of hydroxyl radical. These results indicate that brown-rot fungi produce large amounts of hydroxyl radical for the degradation of wood and crystalline cellulose.