Characterisation of fungal degraded birch wood by FTIR and Py-GC

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. I: 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.