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Quartz crystal microbalance with dissipation monitoring (QCM-D) was used to investigate the fundamental interactions between wood extractives and surfaces used in papermaking. Experiments were carried out at 25 °C and 50 °C on a microcrystalline cellulose-coated surface (a surrogate for paper) and a chromium surface (a surrogate for metal surfaces in paper machines and printing presses) using colloids prepared from wood extractives and model compounds of the components in wood extractives. Differences in adsorption behaviour were observed between the two surfaces as a function of temperature. On both surfaces, triolein and abietic acid were found to deposit to a greater extent than wood extractives, mixed model compounds and oleic acid. At 25 °C the colloids were found to have two phases of adsorption onto cellulose surfaces, an initial rapid adsorption phase followed by a slower phase, compared to a single adsorption phase onto chromium. At 50 °C, only a single adsorption phase was observed on both surfaces. Abietic acid and oleic acid were found to desorb readily from both the cellulose and chromium substrates, while triolein remained strongly adsorbed. However significantly more abietic acid remained on the chromium surface at 25 °C compared to any other tested material, providing a possible explanation for the observed high rates of resin acid deposition onto metal surfaces during papermaking and printing. At 25 °C and 50 °C, less wood extractives and mixed model compound colloids were deposited onto cellulose than onto chromium, which may also explain the high rates of deposition on the metal surface. Stabilisation of the colloids due to interactions between different components within the colloid results in lower deposition of wood extractives and mixed model compound colloids compared to individual component colloids. [ABSTRACT FROM AUTHOR]

The study of decay resistance in wood is of interest for wood end-users but also for the global carbon balance since wood biodegradation is a key driver of forest ecosystem functioning through its impacts on carbon and nutrient cycling. We studied the density and wood extractive contents in order to understand decay resistance against soil microflora after 90 days exposure of sapwood and heartwood from three Neotropical wood species known for their decay resistance: Bocoa prouacensis, Vouacapoua americana, Inga alba. Decay resistance was correlated with density more than wood extractive content. The results highlighted different decay resistance strategies. In B. prouacensis, both sapwood and heartwood were highly resistant due to the high density and high content of antifungal wood extractives. In V. americana heartwood, decay resistance was due to the high synergistic-acting wood extractive content. Conversely, with the least dense wood species I. alba, we found that decay resistance was due to the antifungal wood extractives synthesized early in the sapwood. In conclusion, we showed that the three wood species with the same level of heartwood decay resistance performance had different decay resistance strategies according to the anatomic and defensive wood traits. [ABSTRACT FROM AUTHOR]

Abstract: Two wood extractives, dehydroabietic acid (DHAA) and betulinol (BET), present in wood industry effluents were evaluated for their potential effects on the reproductive physiology of zebrafish. Adult zebrafish (F0) were exposed in a continuous flow-through system to 50μg/l DHAA, 5μg/l BET and 0.27μg/l (1nM) 17β-estradiol (E2) for 3 months. Eggs were collected from F0 fish and the following F1 generation was exposed for 6 months. Biomarkers analyzed in both F0 and F1 fish were plasma vitellogenin (Vtg), testosterone (T), E2 (only females) and gonadal histology. DHAA and BET affected growth in terms of increased condition factor, and spawning was stimulated in BET-exposed fish of the F0 generation. F0 males exposed to DHAA and F0 females exposed to BET showed lower plasma Vtg concentration, but F1 males exposed to BET showed an increase in Vtg. In fish exposed to E2, the positive control for estrogenic effects, a pronounced increase in Vtg concentration was observed. Plasma sex steroids were not significantly affected by the wood extractives. However, although not statistically significant, the T concentration tended to be lower in fish of all BET treatments. The histological study revealed alterations in spermatogenic stages of F0 males exposed to DHAA and BET, which were different from those caused by E2. In F1 females, the percentage of vitellogenic oocytes was decreased in DHAA, BET and E2 exposures. This study shows that DHAA and BET may contribute to growth alterations and reproductive disturbances reported in fish exposed to pulp and paper mill effluents. Further, these wood extractives may have different effects in F0 and F1 generation fish, which highlights the value of two-generation studies in investigations regarding endocrine disrupting compounds. [Copyright &y& Elsevier]

Ebony (Diospyros celebica Bakh.) is an endemic plant on Celebes (Sulawesi) island. Extractive compounds within ebony wood cause it to have durability, strength, and beautiful patterns. In this study, we used near-infrared (NIR) spectroscopy to discriminate between ebony wood samples, based on their origins at different growth sites on Celebes island, and to develop quantitative models to predict the extractive content of ebony wood. A total of 45 wood meal samples from 11 sites located in West, Central, and South Celebes were collected in this study. NIR spectral data were acquired from hot water and ethanol–benzene soluble extracts from ebony wood in this study. The extractive content of the ebony was 10.408% and 10.774% based on hot water solubility and treatment with ethanol–benzene solvent, respectively. Multivariate analysis based on principal component analysis–discriminant analysis revealed that ebony wood from West Celebes differed from most of the wood from South Celebes; however, it was only slightly different from ebony wood from Central Celebes based on NIR spectra data. These findings were in line with the extractive contents obtained. Partial least square regression models based on wood meal spectra could potentially be used to estimate the hot water and ethanol–benzene extractive contents from ebony wood. [ABSTRACT FROM AUTHOR]