Reduction of aldehydes and terpenes within pine wood by microbial activity

Aldehydes and terpenes are the most frequently emitted volatile organic compounds (VOCs) in the wood-processing industry. These emissions are classified as injurious to health and hazardous to the environment. To address this problem, the growth conditions have been identified under which bacteria extensively degrade both aldehydes and particularly terpenes in pine wood particles as a raw material for the production of particle boards. In this study, the focus was on pentanal and hexanal (aldehydes) as well as α- and β-pinene (terpenes). Bacterial strains were selected for their ability to metabolize α-pinene as single carbon source in liquid culture medium. α-Pinene degradation was then determined by gas chromatography (GC) analysis. Strains belonging to the genus showed the best results (98% degradation after 72 h). Comparably good results were also achieved with the thermophilic strain (90% degradation) at 55°C. Furthermore, an adapted mixed culture of species was inoculated onto wood particles and incubated at room temperature for 3 days. Solid-phase microextraction (SPME) measurements of emitted volatiles and subsequent gas chromatography-mass spectrometry (GC-MS) analysis indicated a complete removal (100%) of aldehydes and, even more importantly, α- and β-pinene. Pre-treatment of unsterile pine wood particles with species may have potential for industrial application.