Estimating the chemical composition of biodegraded pine and eucalyptus wood by DRIFT spectroscopy and multivariate analysis

Fourier transformed infra-red (FTIR) was evaluated as an analytical tool fo r monitoring wood biodegradation. A sample set containing typical soft (Pin us radiata) and hardwood (Eucalyptus globulus) decayed by six white- and tw o brown-rot fungi was prepared. Biodegradation times from 30 days to 1 year provided samples that suffered weight losses varying from 0.4% to 36% for pine wood and 1.7% to 42% for eucalyptus wood. Decayed samples were charact erized by conventional wet chemical analysis and by diffuse reflectance FTI R (DRIFT) spectroscopy. Multivariate analysis was applied to correlate chem ical composition in wood samples with the FTIR spectral data. Partial least squares (PLS) models were able to predict the major wood components' conce ntrations at the 99% confidence level presenting r(2) values higher than 0. 86 in most cases. Models for P. radiata were more precise than for E. globu lus. (C) 2000 Elsevier Science Ltd. All rights reserved.