bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cooperation of Fungal Laccase and Glucose 1-Oxidase in Transformation of Björkman Lignin and Some Phenolic Compounds
Authors: Leonowicz Andrzej , Rogalski Jerzy , Jaszek Magdalena , Luterek Jolanta , Wojtas-Wasilewska Maria , Malarczyk Elzbieta , Ginalska Grazyna , Fink-Boots Monika , Cho Nam-Seok 
Published: October 2004

SummaryA screening of wood-rotting basidiomycete fungi was conducted for glucose 1-oxidase (GOD) and laccase (LAC) production as well as for ligninolytic activity measured by a Rhemazol reaction. The results showed that genera rich in GOD are lignin degraders as well as effective producers of extracellular LAC. The fungi poor in GOD neither showed LAC, nor ligninolytic activity. The Björkman lignin and 3 phenolic compounds, hydroquinone and syringic and vanillic acids, were tested on the sequential activity of LAC and GOD. In the presence of LAC, quinoid intermediates formed from Björkman lignin and phenolic compounds were observed. The addition of GOD caused a diminution of the quinone level. During incubation of Björkman lignin with LAC and GOD depolymerization occurred, and in the experiments omitting GOD the quantities of low molecular products were markedly lower. Consequently, the consecutive ping-pong activity of LAC and GOD reduced the polymerization and improved the efficiency of depolymerization processes.
The Lipophilic Extractives of an Interglacial Fossil Picea abies from Zeifen (Germany)
Authors: Staccioli Giuseppe , Sturaro Alberto , Parvoli Giorgio , Menchi Gloria , Matteoli Ugo 
Published: October 2004

Summary
A fossil Picea abies from Zeifen (Germany), 100,000 years old and still presenting good physical and
anatomical properties, is analysed with respect to its lipophilic content. Comparisons are made with a
recent Picea abies, with a subfossil larch and with Taxodioxylon gypsaceum fossils ranging from 1.7
to 20 million years ago. Due to the relatively small age and the low degree of degradation, terpenes
having structures intermediate between the original compounds and the final terpanes are looked for.
Lipophilic components obtained from the fossil Picea abies by extraction with dichloromethane include
linear alkanes, fatty acids, high MWs alcohols and terpenoids such as sesquiterpanes, diterpanes and
diterpenoids. Some of extractive components result unchanged after the process of ageing while others
correspond to substances derived by a process of hydrolysis of original extractives occurring in recent
Picea abies. Diterpanes (norabietatriene, norpimarane, retene and α-phyllocladane) correspond to those
present in most fossils of conifers, even if a trend to the formation of demethylated compounds is
observed. Diterpenoids, on the contrary, are present exclusively as the dehydroabietic acid structure, the
form preceding or responsible of those of most diterpanes, while different structures are not found.
Since intermediate compounds with structures different from the abietic one are absent they might be
looked for in younger fossils. The presence of a large amount of terpanes places this fossil rather closer
to Taxodioxylon gypsaceum samples than to the subfossil larch.
Modified Lignin and Delignification with a CAD-Deficient Loblolly Pine
Authors: MacKay John , Presnell Tim , Jameel Hasan , Taneda Hidetaka , O'Malley David , Sederoff Ronald 
Published: October 2004

Summary
Lignin composition and lignin removal were investigated in loblolly pines (Pinus taeda L.) deficient in
the monolignol biosynthesis enzyme, cinnamyl alcohol dehydrogenase (CAD). The CAD-deficient pines
were homozygous for the cad-n1 allele, a mutant form of the gene encoding CAD. We show that lignin
from CAD-deficient seedlings is more easily removed by mild alkali at room temperature. The nature
of the phenolics recovered from this treatment link the increased lignin solubility to a build up of
aromatic aldehyde lignin subunits. We carried out a retrospective genetic analysis to identify a 12
year-old CAD-deficient tree from which we isolated Milled Wood Lignin (MWL) and obtained wood
chips for pulping studies. The UV absorption spectra of MWL and the effect of sodium borohydride
reduction of MWL showed that the CAD-deficient tree had substantially higher incorporation of
aldehyde subunits. The CAD-deficient wood was delignified more extensively than the wild type in
soda pulping but not in kraft conditions. More extensive lignin removal, both in mild alkali treatment
and in soda pulping, indicate that suppression of CAD in softwood trees may hold promise to produce
woods well suited for “milder” pulping conditions that consume less chemicals and generate less waste.
Polyhydric Alcohol Pulping at Atmospheric Pressure: An Effective Method for Organosolv Pulping of Softwoods
Authors: Uraki Yasumitsu , Sano Yoshihiro 
Published: October 2004

Summary
Polyhydric alcohol pulping was developed to separate components of low-quality softwoods that are
produced by thinning and improvement cutting as well as to establish a self-supporting pulping system.
Propylene glycol (PG) was superior to ethylene glycol (EG) as solvent for polyhydric alcohol pulping
at atmospheric pressure. PG pulping of fir, larch and cedar, with sulfuric acid as a catalyst, gave
satisfactory pulps with few rejects and a very low level of residual lignin as compared with EG pulping.
The PG pulps were readily bleached to approximately Kappa number 1 and 80% brightness by one
treatment with sodium chlorite. The yield of bleached pulp from fir was 44.7% based on chips. The
bleached pulps had very high α-cellulose content and crystallinity, and their mechanical properties were
similar to those of kraft pulp. Therefore, polyhydric alcohol pulping appears to be promising for pulping
of softwoods by an organosolv method.
Oxygen Delignification of High-Yield Kraft Pulp. Part I: Structural Properties of Residual Lignins
Authors: Moe Størker T. , Ragauskas Arthur J. 
Published: October 2004

Summary
The chemistry of oxygen delignification of high-yield kraft pulp was studied by analysis of residual
lignin extracted from kraft and kraft-oxygen pulps using the acid hydrolysis/dioxane extraction method.
For reference pulps cooked to kappa numbers between 20 and 25, the content of free phenolic groups
decreased to about 50% the original value upon oxygen delignification, while the content of carboxylic
acid groups increased by 50–100%. For lignins isolated from high-yield kraft pulp and oxygen
delignified high-yield kraft pulp, it was shown that high-yield kraft pulping with polysulfide (PS) and
anthraquinone (AQ) gives a residual lignin which is chemically different from that of kraft pulps cooked
to lower kappa numbers. Lignin extracted from oxygen delignified high-yield PS/AQ kraft pulp was
more similar to lignins extracted from kraft pulps cooked to lower kappa numbers.
Surface Properties of Mechanical Pulps Prepared under Various Sulfonation Conditions and Preheating Time
Authors: Börås Linda , Gatenholm Paul 
Published: October 2004

Summary
In this study, the mechanical pulps were prepared under different preheating time and sulfonation
conditions. The pulping conditions chosen yield a gradient of pulps ranging from thermomechanical
pulp (TMP) through chemithermomechnical pulp (CTMP) with a low degree of sulfonation to CTMP
with a high degree of sulfonation. The increase of the sodium sulfite charge resulted in a gradient of
sulfur content which was shown to be related to the introduction of strong acidic groups as well as to
the decrease of the carbohydrate content at the surface revealed by Electron Spectroscopy for Chemical
Analysis (ESCA). These results together with Scanning Electron Microscopy (SEM) investigations
confirm that the plane of rupture in the fiber has been transferred to a more lignin-rich area of the
middle lamella. Despite the lower carbohydrate content at the surface, the water wettability of fibers
was increased as revealed by dynamic contact angle. This is explained by the polar contribution of
sulfonated lignin to the surface energy of the fibers. Inverse Gas Chromatography (IGC) analysis
confirmed the differences in the surface properties of the pulps.
Volatile Organic Chemicals Emissions from OSB as a Function of Processing Parameters
Authors: Barry A.O. , Corneau D. 
Published: October 2004

Summary
The effects of the oriented strand board (OSB) furnish drying temperature and moisture content on
VOC emissions were evaluated and compared to those of the OSB pressing time and temperature and
resin content. Results clearly showed the important role played by the drying temperature on the strand
emissions. A decrease of emissions is observed when the furnish at a given original moisture content
had been exposed to increasingly high temperatures. Also, the combined effect of moisture content and
heating temperatures showed an increase of the detected TVOC as moisture content and the temperature
increased. At a very high temperature however, the furnish at low moisture content started to degrade,
and an increase in the emission level could be observed. The results showed that emissions from
oriented strand board (OSB) panels were more sensitive to resin content and pressing time. The
Box-Behnken statistical linear model used to treat the data revealed that a linear fitting better correlates
our results. The correlation between the internal bond (IB) and the panel's emissions indicated a
decrease in emissions as the quality of the board (IB) increases in agreement with better resin curing.
The acquisition of more data will certainly be helpful to support this preliminary study.
The Significance of Accelerated Laboratory Testing Methods Determining the Natural Durability of Wood
Authors: Acker J. Van , Militz H. , Stevens M. 
Published: October 2004

Summary
Under laboratory conditions basidiomycete and soft rot tests were carried out on more than 20 hardwood species and 3 softwood species together with reference species to evaluate their natural durability according to the European standard EN 350 part 1. The basidiomycetes tests were carried out using Gloeophyllum trabeum, Coniophora puteana, Poria placenta and Coriolus versicolor, all fungal strains in malt agar tests and in agreement with the EN 113. Such tests did not provide a solid basis to classify all wood species according to known durability classes (EN 350, part 2). There was only a distinct differentiation noted between those species belonging to the group with a durability classified 1 to 3 and those classified 4 to 5. Conclusively, only limited additional information on durability of tropical hardwoods was gained from brown rot tests. Despite both types of laboratory tests on soft rot, prescribed in ENV 807 (vermiculite and soil) which show the essential differences to the basidiomycete test results, it has not been possible to classify the durability subdivisions in a more substantial way. Adding to these tests the durability classification, based upon a field stake test (EN 252) and a greenhouse accelerated stake test, was also carried out. Using this last method, results can be gathered more rapidly and consequently confirm the efficiency of lab tests. Generally it is perceived that lab tests and accelerated tests are important tools in the prediction of the natural durability of wood. To further improve the predictability value, durability testing would be enhanced when using a hazard class orientation. Therefore the function of the conclusive end product can be identified in a more obvious way.
Fixation of Chromium in Wood from Trivalent Chromium Salt Solutions
Authors: Jorge F. C. , Santos T. M. , Jesus J. Pedrosa de , Banks W.B. 
Published: October 2004

Summary
The aim of this study was to fix chromium chemically in wood from trivalent chromium solutions. Chromium(III) nitrate, chloride and sulphate salts were applied, both in aqueous and in methanolic solutions. To improve chromium fixation metallic zinc was used as a strong reductant to generate labile Cr(II) species from Cr(III), and base was added (NaOH for water and NaMeO for methanol). Aqueous solution reaction conditions were always acidic in spite of base addition, leading to unacceptable levels of wood degradation (e. g., weight loss), although relatively high chromium levels were attained in some cases. Methanolic solutions did not lead to wood degradation, and there was fixation of high levels of chromium. Although the addition of NaMeO seemed to improve chromium fixation, a chromium precipitate always formed, usually after a long reaction time (> 4h). Therefore the following experimental conditions for chromium fixation are suggested: alcoholic solution of Cr(III) chloride or nitrate, addition of metallic zinc, at reflux. To avoid using large amounts of zinc, Cr(III)-solutions can also be reduced electrochemically.
Spatial Distribution of Metal Ions in Spruce Wood by Synchrotron Radiation Microbeam X-Ray Fluorescence Analysis
Authors: Berglund Annica , Brelid Harald , Rindby Anders , Engström Per 
Published: October 2004

Summary
The possibility of using synchrotron radiation microbeam X-ray fluorescence (μ -XRF) for the determination of the morphological distribution of inorganic elements in wood has been investigated. A number of samples were analyzed and some of the results are presented in this paper. The new application of the method showed good results and it was concluded that the technique is useful for specific in situ metal ion analysis of wood. One of its special advantages is that it is a non-destructive method, which may allow analysis of the same sample before and after a chemical treatment. This study shows the natural distribution of a selection of metal ions in wood. Some differences in the distribution and amount of certain metals could also be observed in a sample that had been subjected to treatment with an EDTA-solution.
Chemical Composition of Lipophilic Extractives from Eucalyptus globulus Labill. Wood
Authors: Gutiérrez A. , Río J.C. del , González-Vila F.J. , Martín F. 
Published: October 2004

Summary
The composition of lipophilic extractives in the chloroform soluble fraction of the acetone extract from Eucalyptus globulus wood has been examined. The lipid extract was fractionated by solid-phase extraction on aminopropyl-phase cartridges into four different fractions of increasing polarity. The total lipid extract and the resulting fractions were analyzed by gas chromatography and gas chromatography-mass spectrometry, using high temperature capillary columns. The main compounds identified included sterols, sterol esters, fatty acids, steroid ketones, hydrocarbons and triglycerides. Minor compounds such as fatty alcohols, mono- and diglycerides, waxes and tocopherols were also identified among the lipids from E. globulus wood.
Antifungal Compounds in the Ethyl Acetate Soluble Fraction of the Extractives of Taiwania (Taiwania cryptomerioides Hayata) Heartwood
Authors: Chang Shang-Tzen , Wang Sheng-Yang , Wu Chi-Lin , Su Yu-Chang , Kuo Yueh-Hsiung 
Published: October 2004

Summary
This study was to isolate and identify the antifungal compounds in the ethyl acetate soluble fraction of the methanol extractives of Taiwania (Taiwania cryptomerioides Hayata) heartwood and to examine their antifungal activity. Five compounds were obtained by open column chromatography and HPLC and based upon the results from Mass, 1H-NMR, and 13C-NMR analyses. Their structures were identified, namely ferruginol, helioxanthin, savinin, taiwanin C, and hinokiol. According to the results of antifungal test, the order of antifungal index of these compounds for Coriolus versicolor (L. ex Fr.) Quel. was ferruginol > taiwanin C > savinin > hinokiol. For Laetiporus sulphureus (B. ex Fr.) Bond. it was taiwanin C > savinin > ferruginol > hinokiol.
Efficacy of Pinosylvins against White-Rot and Brown-Rot Fungi
Authors: Celimene Catherine C. , Micales Jessie A. , Ferge Leslie , Young Raymond A. 
Published: October 2004

Summary
Three stilbenes, pinosylvin (PS), pinosylvin monomethyl ether (PSM) and pinosylvin dimethyl ether (PSD), were extracted from white spruce (Picea glauca), jack pine (Pinus banksiana), and red pine (Pinus resinosa) pine cones, and their structures were confirmed by spectroscopic and chromatographic (HPLC, GC/MS, NMR and FTIR) analysis. PS, PSM, PSD or a 1:1:1 mixture of these stilbenes at concentrations of 0.1 % and 1.0 % were examined for their fungal inhibitory activity by two bioassay methods. Growth of white-rot fungi (Trametes versicolor and Phanerochaete chrysosporium), and brown-rot fungi (Neolentinus lepideus, Gloeophyllum trabeum and Postia placenta) on agar media in the presence of each of the stilbenes or a 1:1:1 mixture inhibited growth of white-rot fungi, but slightly stimulated growth of brown-rot fungi. Soil-block assays, conditions more representative of those found in nature, did not correlate with those from the screening on agar media. PS, PSM, PSD or a 1:1:1 mixture of the three compounds at concentrations of 0.1 % and 1.0 % did not impart any significant decay resistance to white-rot fungi inoculated on a hardwood (Red maple). However under the same conditions, decay resistance was observed against brown-rot fungi on a softwood (Southern yellow pine). It appears that stilbenes at least partially contribute to wood decay resistance against brown-rot fungi.
Lignin-Polyphenol Interaction in Azobe (Lophira alata) Heartwood. A Study on Milled Wood Lignin (MWL) and Klason Residues
Authors: Lange Werner , Faix Oskar 
Published: October 2004

Summary
Findings about anomalous high Klason residues of azobe (Lophira alata) heartwood prompted a search for methods of determination of non lignin-type polyphenols in lignin preparations. A four step procedure was performed: (1) ethylation of milled wood lignins (MWLs) from azobe and beech heartwood, (2) permanganate oxidation, (3) methylation, and (4) GC analysis of the oxidation products. Besides the well known degradation products of hemipinic, iso-hemipinic, and meta-hemipinic acid type, methyl-3,4-diethoxy-benzoate (compound I) has also been detected among the oxidation products. The oxidation of beech MWL gave rise only to 0.4 mol % of I but azobe MWL yielded the remarkably high amount of 10.7 mol % of I. As lignins do not contain two adjacent aromatic hydroxyl groups, we concluded that I is of polyflavonoid origin. Hence the extraordinarily high Klason residues of azobe heartwood can be rationalized with large amounts of acid insoluble polyphenols which are an integral part of the azobe cell wall and which is also closely associated to MWLs. Ethylation followed by KMnO4 oxidation is an effective tool to detect polyflavonoids in lignins.
Determination of Phenolic Hydroxyl Groups in Lignin by Combined Use of 1H NMR and UV Spectroscopy
Authors: Tiainen Eija , Drakenberg Torbjörn , Tamminen Tarja , Kataja Kirsi , Hase Anneli 
Published: October 2004

Summary
Two independent spectroscopic methods are presented and compared for the quantitation of the phenolic hydroxyl groups in lignins. The combined information is used to further elucidate the character of the lignin samples examined. The UV method is based on the difference of the spectroscopic properties of the ionised and the nonionised phenol. The method using 1H NMR spectroscopy is based on the exchange of phenolic protons in D2O. The difference in integrated proton intensities in the sample dissolved in DMSO and the sample with additional 20% D2O is proportional to the phenolic protons. The method based on UV spectroscopy uses differences in the maxima close to 300 nm and 350 nm of the sample dissolved in alkali and the neutral sample. The results using the two independent methods are in agreement for milled wood lignin, for kraft lignin and for model compounds carrying one aromatic hydroxyl group. For modified lignins and for model compounds with more than one aromatic hydroxyl group, the UV method gives too low values for phenolic hydroxyl groups. The combined results obtained by the two methods however provide information of the total amount of the phenolic groups and of the nature of the phenolic structure formed by the lignin refining.
The Effective Diffusion Coefficient and Mass Transfer Coefficient of Nordic Softwoods as Calculated from Direct Drying Experiments
Authors: Hukka Antti 
Published: October 2004

Summary
The effective diffusion coefficient and mass transfer coefficient of Scot's pine and Norway spruce heartwood are calculated from the measured development of the internal moisture profiles of sawn timber during drying. Measurement is made using the oven-dry method. Calculation of both coefficients is based on using an existing timber drying simulation model to iteratively optimise the parameter values for the diffusion and mass transfer coefficients of prescribed functional form. The results show that the procedure employed is a feasible method to obtain numerical values for the internal and external transfer coefficients as functions of wood moisture content and temperature. The resulting diffusion coefficient and mass transfer coefficient are applicable in the whole moisture range between green and dry states in temperatures 20–80°C thus covering the whole process of medium-temperature wood drying.
Sorption Behaviour and Dimensional Changes of Wood-Coating Composites
Authors: Meijer Mari de , Militz Holger 
Published: October 2004

Summary
The moisture related properties of wood-coating composites have been studied to evaluate the influence of coating penetration on the protection of wood against moisture. Pine sapwood samples were vacuum-impregnated with 7 pigmented and unpigmented coatings, both water and solvent borne. The retention and void filling of the coating have been determined. After drying, the samples were exposed to relative humidities between 33 and 98 % and to liquid water and equilibrium moisture content and dimensional changes were measured. The rate of swelling and moisture sorption has been measured, the latter was also used to calculate diffusion coefficients. The sorption isotherms were analysed by the Hailwood-Horrobin equation. In order to obtain additional information on the hygroscopicity of coatings, similar measurement were made on free coating films.
The void filling of wood with coating material has the strongest impact on the uptake of liquid water. A limited reduction was observed for the equilibrium moisture content, the diffusion coefficient during adsorption and the rate of dimensional change. No influence on the equilibrium swelling have been found but the shrinkage during desorption was however often slightly increased for the wood-coating composites.
The limited impact of the penetrated coating on moisture related properties can to a large extent be explained by the low void filling after drying (20–60%) and the relatively high moisture sorption and swelling of the coating film itself. In general, it can be concluded that the moisture protection of penetrated coating material is low in comparison to coating applied as a film on the surface of wood.