An FT-IR study of the changes in chemical composition of bamboo degraded by brown-rot fungi

• Published in: International biodeterioration & biodegradation 2013-11, Vol.85, p.131-138
• Main Authors: Tomak, Eylem D., Topaloglu, Elif, Gumuskaya, Esat, Yildiz, Umit C., Ay, Nurgul
• Format: Article
• Language: English
• Subjects: absorption; Aging; Bamboo; bamboos; biodegradation; Brown-rot fungi; cellulose; Chemical attack; Chemical composition; Coniophora puteana; crystal structure; Crystallinity; culms; Decay; decay resistance; Degradation; Fourier transform infrared spectroscopy; FT-IR; Fungi; lignin; Placenta; Rhodonia placenta; Weight loss; wood
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/j.ibiod.2013.05.029

The objective of this study was to use FT-IR analysis to investigate the chemical composition of aged and un-aged bamboo specimens, with and without node sections, decayed by brown-rot fungi. Specimens were exposed to two brown-rot fungi, Coniophora puteana and Poria placenta, for 8 weeks after which decay was assessed by weight loss and FT-IR spectra analysis. Depending on the bamboo section examined, the aging process reduced decay resistance of specimens. Weight loss (measured as a percentage) decreased from the top to the bottom portion of bamboo culms. The presence of nodes in the specimens increased weight loss caused by P. placenta attack, and caused only a slight increase in weight loss from C. puteana attack. Significant chemical changes in bamboo were observed after fungal degradation, as revealed by FT-IR analyses. Consistent with the degradation mechanism of brown-rot fungi, lignin was essentially un-degraded or modified. Both brown-rot fungi caused a sharp decrease in the carbonyl absorption area. Surprisingly, cellulose peaks of degraded specimens were nearly similar to the peaks of control specimens. Aging treatments and biodegradation affected the crystalline structure of bamboo specimens. Poria placenta degraded wood components faster and changed the crystallinity more than C. puteana did, in accordance with the weight losses due to decay. •Samples with and without node section from three portions of bamboo culms were studied.•Accelerated aging decreased decay resistance of samples against brown-rot fungal attack.•Weight loss decreased from top to bottom portion of bamboo culms.•Brown-rot fungi caused a sharp decrease in the carbonyl absorption area.•Aging treatments and biodegradation affected crystalline structure of bamboo samples.