Characterisation of Fungal Degraded Birch Wood by FTIR and Py-GC

Abstract

Rot fungi Fomitopsis pinicola and Sterum hirsutum were employed in preparing decayed birch wood samples. The degree of decay was determined as weight loss. The samples were analysed by analytical pyrolysis (PY) and infrared spectroscopy (FTIR) and correlated to weight loss by means of multivariate calibration.The above techniques provided both quantitative assessments and qualitative interpretations. The PY technique can distinguish between the fungi at all degrees of decay while FTIR failed at low weight losses. This may be due to fungal biomass, the amount of which is difficult to determine in the decayed sample. Both analytical techniques can be calibrated to predict weight losses from 0 to 45 %. Different fungal degradation patterns could also be identified, especially when pyrolysis was used. F. pinicola degraded lignin to a lesser extent at the same weight loss than did S. hirsutum. General degradation mechanisms could be confirmed for the fungi studied. KeywordsFomitopsis pinicola Sterum hirsutum Decayed birch wood FTIR Analytical pyrolysis Multivariate data analysis Brought to you by | University of Arizona Authenticated Download Date | 6/3/15 4:21 PM

Deterioration of the Hanson Logboat: chemical and imaging assessment with removal of polyethylene glycol conserving agent

“…The ensuing greater degree of polymerisation of guaiacyl units potentially makes them more resistant to enzymatic attack 21,22 . Another plausible explanation is that many lignolytic microbes may preferentially attack the secondary cell wall layers that are richer in syringyl lignin, leaving the guaiacyl lignin rich inner lamella intact and hence having a greater impact on syringyl units than on guaiacyl units 42 .…”

Lignin attack during eucalypt wood decay by selected basidiomycetes: a Py-GC/MS study

“…It may also be due to the manner in which the different white-rot basidiomycetes degrade wood, i.e. the fungi first erode or delignify the S-rich secondary wall leaving the G-rich cell corners to a latter stage of degradation [9]. Some differences were observed in the relative abundances of the released lignin and carbohydrate-derived compounds and, therefore, in the general degradation pattern caused by the different basidiomycetes.…”

“…White-rot fungi decompose the lignin in wood opening access to the cellulose and hemicelluloses that are embedded in the lignin matrix. Analytical pyrolysis coupled to gas chromatography/mass spectrometry (Py-GC/MS) proved to be a useful tool to detect the fungal reworking and the extent of fungal degradation of lignocellulosic constituents, which cannot be straight-forwardly detected with the standard gravimetric methods [3][4][5][6][7][8][9][10]. Lignin is pyrolyzed to produce a mixture of relatively simple phenols, which result from cleavage of ether and certain C-C inter-unit linkages [3][4][5].…”

FT-IR imaging microscopy to localise and characterise simultaneous and selective white-rot decay within spruce wood cells

“…This technique is also powerful in investigating the composition of biodegraded wood Ferraz et al 2000;Pandey and Pitman 2003;Backa et al 2001;Fackler et al 2007c). Recently, FT-IR microscopy was helpful to examine the orientation of the main wood polymers in transversal and longitudinal direction of spruce fibres (Stevanic and Salmén 2009), but the application of this technique is not a trivial matter for investigation of wood on the cellular level.…”