Chaetomium as Potential Soft Rot Degrader of Woody and Papery Cultural Heritage

Abstract

Wood decay by fungi is typically classified into three types: soft rot, brown rot, and white rot. Brown rot fungi are the most prevalent with regard to attack on coniferous, structural wood products. The wood decayed by brown rot fungi is typically brown and crumbly and it is degraded via both nonenzymatic and enzymatic systems. A series of celluloytic enzymes are employed in the degradation process by brown rot fungi, but no lignin-degrading enzymes are typically involved. White rot fungi are typically associated with hardwood decay and their wood decay patterns can take on different forms. White rot fungi possess both cellulolytic and lignin-degrading enzymes, and these fungi therefore have the potential to degrade the entirety of the wood structure under the correct environmental conditions. Soft rot fungi typically attack higher moisture and lower lignin content wood and can create unique cavities in the wood cell wall. Less is known about the soft rot degradative enzyme systems, but their degradative mechanisms, with special reference to Chaetomium, are reviewed along with the degradative enzymatic and nonenzymatic systems known to exist in the brown rot and white rot fungi.