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Meticulous chemical analysis of decaying xylem and linking it to corresponding anatomical modification at the cellular level can improve our understanding of the decay process. The aim of this study was to monitor the histological, chemical, photochemical, and progression of wood degradation by two white-rot fungi at different intervals. Oriental beech wood (Fagus orientalis) blocks were exposed to Pleurotus ostreatus and Trametes versicolor to investigate the degradation capabilities of these two fungi. Light microscopy was used to study the decay patterns in wood. Decayed wood samples were also analyzed to determine lignin, cellulose and sugar contents and also evaluated at two week intervals by FT-IR spectroscopy to study chemical alterations. According to chemical analyses lignin is the most degraded polymer followed by cellulose and hemicelluloses for both white rot fungi. However, both test fungi tended to consume lignin more than cellulose. FT-IR spectra changes for lignin and carbohydrates in beech wood supported chemical alteration and indicated that both fungi decay wood in a simultaneous pattern.

The biotechnological potential of nine decay fungi collected from stored beech logs at a pulp and paper factory yard in Northern Iran was investigated. Beech blocks exposed to the fungi in a laboratory decay test were used to study changes in cell wall chemistry using both wet chemistry and spectroscopic methods. Pleurotus ostreatus, P. pulmonarius, and Lentinus sajor-caju caused greater lignin breakdown compared to other white-rot fungi, which led to a 28% reduction in refining energy. Trametesversicolor caused the greatest glucan loss, while P. ostreatus and L. sajor-caju were associated with the lowest losses of this sugar. Fourier transform infrared spectroscopy (FTIR) analyses indicated that white-rot fungi caused greater lignin degradation in the cell walls via the oxidation aromatic rings, confirming the chemical analysis. The rate of cellulose and lignin degradation by the T.versicolor and Pleurotus species was high compared to the other decay fungi analyzed in this study. Based on the above information, we propose that, among the fungi tested, P. ostreatus (27.42% lignin loss and 1.58% cellulose loss) and L. sajor-caju (29.92% lignin loss and 5.95% cellulose loss) have the greatest potential for biopulping.