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[Study on odor control using wood vinegars (II). Application of wood vinegars to piggery wastes].

The effectiveness of wood vinegars was studied for controlling offensive odors from piggery wastes. Odorant chemicals and the sense of odors from piggery farm, covered with polyvinylchloride film to prevent the volatilization to ambient air, were measured in both laboratory and in situ in order to evaluate the degree of deodorization. The results obtained were as follows: 1. The odorant chemicals from piggery wastes were identified as ammonia, methyl sulfide, hydrogen sulfide, butyric acid and valeric acid. Among them, the major chemicals being responsible for the sense of odor were butyric acid and valeric acid. 2. In a laboratory experiment using an air tight vessel, the amount of wood vinegars needed for deodorization of piggery wastes was 6.6%; The removal efficiency of the odorant chemicals volatilized from the wastes was from 70 to 90% of control levels. 3. In situ test at a piggery farm showed that removal efficiency of odorant chemicals was similar to that of the laboratory experiment. In sensory tests, authorized by the Environmental Protection Agency of Japan, minimal offensive odors were observed with the addition of 6.6% wood vinegars. Furthermore, flies were rarely observed, indicating that wood vinegars may play an important role as a repellent.

Acetates↗

Case report of occupational asthma due to palisander wood dust and bronchoprovocation challenge by inhalation of pure wood dust from a capsule.

Occupational asthma due to exposure to exotic wood dust and to rosewood (Dalbergia family) has been reported earlier. This paper deals with a case of occupational asthma due to palisander wood dust (Dalbergia nigra) in a joiner who sanded and polished parts of musical instruments. The causal relationship was confirmed by a positive skin reaction to an allergenic preparation and a positive nonimmediate, late asthmatic reaction after inhalation challenge testing with pure palisander wood dust. A method of bronchoprovocation testing with an occupational allergen is presented. It proved to be a practical and advantageous method in its simplicity and single-blind application of placebo. It should, however, be used with great caution, in well-chosen cases in whom nonspecific bronchial reactivity is proved or recorded to be in normal ranges.

Asthma↗

Interspecific interactions between the rare tooth fungi Creolophus cirrhatus, Hericium erinaceus and H. coralloides and other wood decay species in agar and wood.

Creolophus cirrhatus, Hericium erinaceus and H. coralloides were paired against over 20 other wood decay fungi from beech (Fagus sylvatica) covering a range of ecological strategies, on 2% malt agar (MA), 0.5% MA, 0.5% MA adjusted to -1.25 MPa by addition of KCl, 0.5% MA adjusted to pH 4 with KOH/H3PO4 and 0.5% MA under 5% O2/30% CO2 all at 20 degrees C. Creolophus cirrhatus and H. coralloides were also paired against 17 other species in wood, incubated at 20 degrees for 36-38 wk. They were average to good combatants, deadlocking with or replacing over half of the antagonists, H. erinaceus being slightly more combative than the other two species. Outcomes in wood were representative of those in agar. Abiotic conditions altered the outcomes slightly, reduced water potential favouring C. cirrhatus and H. erinaceus. Overall extension rate of C. cirrhatus and H. erinaceus often increased in the presence of antagonists. There was prolific production of fruit bodies in controls and interactions, though notably not under altered gaseous regime. Results are discussed in an ecological context.

Agar↗

Trace analysis of pentachlorophenol (PCP) in wood and wood-based products--comparison of sample preparation procedures.

The main problem with routine analyses of pentachlorophenol (PCP) and sodium pentachlorophenolate (Na-PCP) in wood and wood-based products is to determine critical PCP-contents. This task requires a reliable analytical method and statistical testing. An analytical procedure is described, which permits the determination of PCP and Na-PCP with sufficient sensitivity and accuracy. A medium size sieve (4 x 4 mm quadratic mesh) was found suitable for the grinding step. Different extraction techniques and solvents were tested systematically. Extraction by a combination of ultrasonication and shaking in the solvent mixture toluene/sulfuric acid showed best recoveries. The eluted PCP and Na-PCP were derivatized with acetic anhydride and determined by GC/ECD. The limits of detection and determination were 0.14 mg/kg and 0.40 mg/kg, respectively.

Acetic Anhydrides↗

Production of wood decay enzymes, loss of mass, and lignin solubilization in wood by diverse tropical freshwater fungi.

In vitro production of cellulase and xylanase was common among diverse freshwater ascomycetes and their hyphomycetous anamorphs. Production of enzymes involved in lignin degradation was rare. Most isolates were capable of causing mass loss in angiosperm wood, although values were low, at approximately 10% during a 24-week period. A few isolates caused higher mass loss of up to 26.5%, and five of these were shown to solubilize significant amounts of lignin. This is the first report of lignin solubilization by freshwater fungi. Torula herbarum (hyphomycete) and Ophioceras dolichostomum (ascomycete) produced indices of lignin solubilization equivalent to those of terrestrial white-rot basidiomycetes. In all cases wood decay was 2.2- to 3-fold higher in exposed rather than submerged conditions.

Cellulase↗

Properties and toxicity of airborne wood dust in wood-working establishments.

The total suspended dust levels, particle shape and size distributions and metal concentrations (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) of wood dust in the breathing zone of 3 small wood-working establishments were monitored. In vitro culture assay indicated that the mortality of alveolar macrophage was related to the metal content of dust collected from these 3 workplaces.

Air Pollutants, Occupational↗

The emision of corrosive vapours by wood. Hot-water-extracted O-acetylated hemicelluloses from sweet chestnut (Castnaea sativa) and wych elm (Ulmus glabrau) and a discussion of O-acetyl-group changes occurring in these woods during incubation at 48 degrees and 100 per cent relative humidity.

1. O-Acetylated polysaccharides were obtained from green wood of both sweet chestnut and wych elm by treatment of the residue remaining after dimethyl sulphoxide extraction with water at 98 degrees . This gives a mixture of polysaccharides containing xylose, galactose, glucose and uronic acids. Analysis of these and their fractionated products suggest that only xylans in green sweet chestnut and green wych elm are O-acetylated. 2. The isolated O-acetylated xylans are not representative of the total O-acetylated xylans occurring in sweet chestnut and wych elm. 3. Application of the method developed by Bouveng for the location of O-acetyl groups to all four O-acetylated xylans obtained in this series of investigations by dimethyl sulphoxide extraction showed that those from sweet chestnut and wych elm, under the same conditions of incubation, lost: 74.2 and 43.4% of acetyl groups respectively, at C-2; 58.0 and 28.5% of acetyl groups respectively at C-3; 41.8 and 82.2% of acetyl groups respectively at C-2 and C-3. 4. A consideration of electronic and steric factors indicates that there does not appear to be a purely chemical reason for the difference in loss of O-acetyl groups between sweet chestnut and wych elm. It is suggested that the location of O-acetylated xylans in the wood cell walls and the presence of extractive may play some part in this difference.

Acetates↗

Utilization of polar metabolite profiling in the comparison of juvenile wood and compression wood in loblolly pine (Pinus taeda).

Juvenile wood (JW) of conifers is often associated with compression wood (CW), with which it is sometimes believed to be identical. To determine whether JW and CW can be distinguished metabolically, we compared gas chromatographic profiles of 25 polar metabolites from rooted cuttings of a single loblolly pine (Pinus taeda L.) clone raised in controlled environment chambers and subject to three treatments: (1) grown erect with minimal wind sway (control); (2) swayed by wind from oscillating fans; and (3) with 30-cm growth increments successively bent at an angle of 45 degrees to the vertical. Profiles were compared by principal component analysis. Substantial increases in abundances of coniferin and p-glucocoumaryl alcohol separated immature JW-forming xylem tissues of the control trees from the CW-forming xylem of the bent and swayed trees.

Carbohydrates↗

Biological degradation of resin acids in wood chips by wood-inhabiting fungi.

Resin acids in many pulp mill effluents are primary sources of toxicity to fish. Inconsistent biological detoxification of chlorinated and nonchlorinated resin acids in secondary treatment of pulp mill effluents is a continuing source of concern. An alternative approach to effluent detoxification is to remove or modify the toxic compounds present in wood chips prior to pulping. Results from experiments in which lodgepole pine sapwood chips were inoculated with several fungal candidates indicate that the total resin acid content can be reduced by up to 67% after fungal growth. Such a treatment could be an efficient and environmentally acceptable way for deresinating wood chips and so decreasing the toxicity of pulp mill effluents.

Biodegradation, Environmental↗

Identification of QTLs influencing wood property traits in loblolly pine ( Pinus taeda L.). II. Chemical wood properties.

Chemical wood property traits were analyzed for the presence of quantitative trait loci (QTLs) in a three-generation outbred pedigree of loblolly pine ( Pinus taeda L.). These traits were assayed using pyrolysis molecular beam mass spectrometry and include mass spectrum peak intensities associated with carbohydrates, alpha-cellulose and hemicellulose sugars, and lignin. Models for projection to latent structures (PLS) were used to also estimate the chemical composition of cell walls (i.e., alpha-cellulose, galactan and lignin) from mass spectrum data using multivariate regression. Both earlywood and latewood fractions from the fifth annual ring were analyzed for each trait. An interval mapping approach designed for an outbred pedigree was used to estimate the number of QTLs, the magnitude of QTL effects, and their genomic position. Eight unique QTLs influencing cell wall chemistry were detected from multiple peak intensities and/or PLS estimates using the one- and two-QTL models. Significant differences in chemical contents were observed among the populations from North Carolina vs Oklahoma, and results from QTLxenvironment analyses suggest that QTLs interact with environmental location. QTLs should be verified in larger experiments and in different genetic and environmental backgrounds. QTL mapping will help towards eventually identifying genes having a major effect on chemical wood properties.

Journal Article↗

The Hook Lake Wood Bison Recovery Project: can a disease-free captive wood bison herd be recovered from a wild population infected with bovine tuberculosis and brucellosis?

The Hook Lake Wood Bison Recovery Project (HLWBRP) is a wildlife conservation project aimed at recovering a captive, disease-free herd of wood bison (Bison bison athabascae) from a wild herd infected with bovine tuberculosis (Mycobacterium bovis) and brucellosis (Brucella abortus). The disease eradication protocol that we have used involves a combination of techniques, including (1) orphaning of newborn wild-caught calves to minimize exposure to B. abortus and M. bovis, (2) testing calves for maternal antibodies to brucellosis in the field prior to inclusion in the project, (3) isolating calves in pairs to prevent potential spread of disease, (4) prophylactic treatment using antimycobacterial and anti-Brucella drugs, and (5) an intensive whole-herd testing program for both diseases and removal of reactors. From 1996 to 1998, we captured a total of 62 calves; presently, 58 individuals comprise the founder herd. The captive-born cohorts consist of 7 two-year-olds, 21 yearlings, and 22 calves. To date, there have been no cases of bovine tuberculosis or brucellosis in the captive herd.

Alberta↗

Mercury residues in wood ducks and wood duck foods in eastern Tennessee.

Liver, breast muscle and body fat from 50 juvenile and five adult wood ducks (Aix sponsa) collected on the Holston River, Tennessee were analyzed for total mercury content. Black fly larvae (Simulium vittatum) sago pondweed (Potamogeton pectinatus), tapegrass (Vallisneria americanus), water stargrass (Heteranthera dubia), Elodea canadensis, and river bottom sediments were also analyzed to elucidate the distribution of mercury in the wood duck's environment. Liver tissues of juveniles contained the highest mean concentration of mercury (0.42 ppm). Mercury in breast muscle and body fat of juveniles averaged 0.15 and 0.10 ppm, respectively. Residues in corresponding tissues of adults were lower. Of environmental components tested, sediments had the highest mean concentration (0.76 ppm). Black fly larvae and aquatic plants had mean levels below 0.10 ppm.

Adipose Tissue↗

[Cocobolo wood, a forgotten eczematogen? Recent findings on the skin allergen of cocobolo wood (Dalbergia sp.)].

Delayed hypersensitivity due to occupational contact with Cocobolo wood and playing the recorders manufactured from this species was proven in three of five patients by positive results in patch tests with its constituents R-4-methoxydalbergione and obtusaquinone. The biogenetic correlations of these isomeric compounds, the strong epicutaneous reactions in the patients as well as the strong sensitizing capacity of obtusaquinone obtained in guinea pig sensitization experiments corroborate the supposition not to consider the dalbergione but the quinone methide (obtusaquinone) as the inductor of Cocobolo hypersensitivity. As both constituents possess inhibitory activity toward marine micro-organisms, such as the marine borer Teredo navalis, they are intended to be used in ship paintings and protection coatings. Thus, Cocobolo will no longer remain a forgotten sensitizer but will become--in case of realization--a risk for certain painters in the future.

Allergens↗