Extracts from teak wood industrial waste: decay performance of treated wood after artificial weathering

Abstract This study aimed to evaluate the preservative potential of extracts from teak wood industrial waste against artificial weathering and decay fungi. Teak extracts were obtained in hot water, acetone, ethanol and methanol and tested against brown-rot ( Rhodonia placenta , Gloeophyllum trabeum , Neolentinus lepideus ) and white-rot fungi ( Irpex lacteus ). Aging tests included the leaching test and artificial weathering in a QUV accelerated weathering tester. The chemical analysis of the extracts was carried out by gas chromatography-mass spectrometry (GC-MS), and the compounds were compared with the cited literature. The extracts were characterized as quinone derivatives (35 %), mainly tectoquinone (28 %), followed by squalene (8–12 %) and other phenolic compounds (6 %). Lapachol, although found in proportions of 0.7–0.9 %, plays an important role in wood durability and biocidal activity in teak extracts. The results obtained by the chemical analysis indicated that the main compounds identified in this study can act synergistically on the resistance of wood impregnated. Teak extracts ensured high resistance to the decay fungi tested and results showed better performance of acetone extracts. In view of the results obtained, it is recommended to carry out other tests (soil bed and field tests) to verify the long-term effects of the extracts.