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Ana Gutierrez - One of the best experts on this subject based on the ideXlab platform.
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omics analyses and biochemical study of phlebiopsis gigantea elucidate its degradation strategy of Wood Extractives
Scientific Reports, 2021Co-Authors: Mana Iwata, Ana Gutierrez, Gisela Marques, Grzegorz Sabat, Philip J Kersten, Daniel Cullen, Jennifer M Bhatnagar, Jagjit S Yadav, Anna Lipzen, Yuko YoshinagaAbstract:Wood Extractives, solvent-soluble fractions of Woody biomass, are considered to be a factor impeding or excluding fungal colonization on the freshly harvested conifers. Among Wood decay fungi, the basidiomycete Phlebiopsis gigantea has evolved a unique enzyme system to efficiently transform or degrade conifer Extractives but little is known about the mechanism(s). In this study, to clarify the mechanism(s) of softWood degradation, we examined the transcriptome, proteome, and metabolome of P. gigantea when grown on defined media containing microcrystalline cellulose and pine sapWood Extractives. Beyond the conventional enzymes often associated with cellulose, hemicellulose and lignin degradation, an array of enzymes implicated in the metabolism of softWood lipophilic Extractives such as fatty and resin acids, steroids and glycerides was significantly up-regulated. Among these, a highly expressed and inducible lipase is likely responsible for lipophilic extractive degradation, based on its extracellular location and our characterization of the recombinant enzyme. Our results provide insight into physiological roles of Extractives in the interaction between Wood and fungi.
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lipophilic Extractives in process waters during manufacturing of totally chlorine free kraft pulp from eucalypt Wood
Chemosphere, 2001Co-Authors: Ana Gutierrez, Javier Romero, Jose C Del RioAbstract:The chemical composition of lipophilic Extractives from process waters throughout a totally chlorine free (TCF) bleaching sequence after kraft pulping of eucalypt Wood has been studied. These compounds are among the most problematic Wood constituents for both TCF and zero liquid effluent (ZLE) processes, since they tend to accumulate in circuits resulting in the formation of the so-called pitch deposits causing serious problems in the pulp and paper industry. Pitch deposits collected at different parts of the pulp mill were also characterized and their composition compared with that of lipophilic compounds in process waters and Eucalyptus globulus Wood. The identification of these compounds from process waters, Wood and pitch deposits was performed by gas chromatography and gas chromatography-mass spectrometry using short- and medium-length high temperature capillary columns. Sterols, sterol esters, steroid ketones and steroid hydrocarbons were the main compounds identified. These chemical species arise from eucalypt Wood Extractives that survive the pulping and are released from pulp into the process waters during the bleaching process. Finally, they can deposit in pulp and on different parts of the mill or remain suspended in process waters being discharged in effluents.
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lipophilic Extractives from eucalyptus globulus pulp during kraft cooking followed by tcf and ecf bleaching
Holzforschung, 2001Co-Authors: Ana Gutierrez, Javier RomeroAbstract:IntroductionWood resin, which consists of complex mixtures of differ-ent lipophilic Wood Extractives including fatty acids, resinacids, waxes, sterols, sterol esters and glycerides, causessignificant technical and economic troubles during pulp andpaper manufacturing (Sjostrom 1993). During Wood pulp-ing and refining of pulp, Extractives in the resin canals andray parenchyma cells can be released forming colloidalpitch. Pitch particles, which can be small in size, then coa-lesce into larger droplets which deposit on the surface offibers or equipment being responsible for production trou-bles and an increased incidence of quality defects (Hillisand Sumimoto 1989). In the production of bleached kraft pulp, a large part ofthe resin originally present in Wood is removed in the kraftcooking. However, the Wood Extractives remaining in thebrownstock pulp will be carried over to the bleach plantwhere they will react with the bleaching chemicals to vari-ous degrees depending on their chemical structure and onthe bleaching agent used (Jansson et al. 1995). The speciesthat survive the bleaching processes can be found as pulpExtractives and are detrimental for product quality. The newtrends to use environmentally-sound bleaching processessuch as “totally chlorine free” (TCF) in place of “elementalchlorine free” (ECF) sequences, are increasing the severityof pitch problems during kraft pulping of some types ofWood.Traditionally, pitch deposits in pulping and paper manu-facture have been reduced by debarking and seasoning logsand Wood chips and by adding physicochemical controlagents (Allen 1988; Dreisbach and Michalopoulos 1989;Allen et al. 1991). However, the cost is high and often theresults are far from satisfactory. As an alternative to theabove, biological removal of Wood Extractives by treatmentwith enzymes (Fischer and Messner 1992; Fujita et al.1992; Fischer et al. 1993) or microorganisms (Farrell et al.1993; Fischer et al. 1994; Gao et al. 1994; Behrendt andBlanchette 1997) has been suggested in recent years forpitch control. The biotechnological preparations commer-cially available are not effective for pitch control duringpulping of eucalypt Wood, which is extensively used as pulpraw material in Spain, Portugal, Brazil and other countries.This is because they are based on enzymes (such as lipasecommercialized by Novo Nordisk as Resinase
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fungal screening for biological removal of Extractives from eucalyptus globulus Wood
Botany, 1999Co-Authors: Maria Jesus Martinez, Jose C Del Rio, Ana Gutierrez, Jose Maria Barrasa, Angel T MartinezAbstract:Wood Extractives cause production troubles during pulp and paper manufacture. The potentiality of fungal strains for biotechnological removal of Extractives from Eucalyptus globulus Labill. Wood is...
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fungal degradation of lipophilic Extractives in eucalyptus globulus Wood
Applied and Environmental Microbiology, 1999Co-Authors: Ana Gutierrez, Jose C Del Rio, Maria Jesus Martinez, Angel T MartinezAbstract:Solid-state fermentation of eucalypt Wood with several fungal strains was investigated as a possible biological pretreatment for decreasing the content of compounds responsible for pitch deposition during Cl2-free manufacture of paper pulp. First, different pitch deposits were characterized by gas chromatography (GC) and GC-mass spectrometry (MS). The chemical species identified arose from lipophilic Wood Extractives that survived the pulping and bleaching processes. Second, a detailed GC-MS analysis of the lipophilic fraction after fungal treatment of Wood was carried out, and different degradation patterns were observed. The results showed that some basidiomycetes that decreased the lipophilic fraction also released significant amounts of polar Extractives, which were identified by thermochemolysis as originating from lignin depolymerization. Therefore, the abilities of fungi to control pitch should be evaluated after analysis of compounds involved in deposit formation and not simply by estimating the decrease in the total extractive content. In this way, Phlebia radiata, Funalia trogii, Bjerkandera adusta, and Poria subvermispora strains were identified as the most promising organisms for pitch biocontrol, since they degraded 75 to 100% of both free and esterified sterols, as well as other lipophilic components of the eucalypt Wood Extractives. Ophiostoma piliferum, a fungus used commercially for pitch control, hydrolyzed the sterol esters and triglycerides, but it did not appear to be suitable for eucalypt Wood treatment because it increased the content of free sitosterol, a major compound in pitch deposits.
Jose C Del Rio - One of the best experts on this subject based on the ideXlab platform.
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lipophilic Extractives in process waters during manufacturing of totally chlorine free kraft pulp from eucalypt Wood
Chemosphere, 2001Co-Authors: Ana Gutierrez, Javier Romero, Jose C Del RioAbstract:The chemical composition of lipophilic Extractives from process waters throughout a totally chlorine free (TCF) bleaching sequence after kraft pulping of eucalypt Wood has been studied. These compounds are among the most problematic Wood constituents for both TCF and zero liquid effluent (ZLE) processes, since they tend to accumulate in circuits resulting in the formation of the so-called pitch deposits causing serious problems in the pulp and paper industry. Pitch deposits collected at different parts of the pulp mill were also characterized and their composition compared with that of lipophilic compounds in process waters and Eucalyptus globulus Wood. The identification of these compounds from process waters, Wood and pitch deposits was performed by gas chromatography and gas chromatography-mass spectrometry using short- and medium-length high temperature capillary columns. Sterols, sterol esters, steroid ketones and steroid hydrocarbons were the main compounds identified. These chemical species arise from eucalypt Wood Extractives that survive the pulping and are released from pulp into the process waters during the bleaching process. Finally, they can deposit in pulp and on different parts of the mill or remain suspended in process waters being discharged in effluents.
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fungal screening for biological removal of Extractives from eucalyptus globulus Wood
Botany, 1999Co-Authors: Maria Jesus Martinez, Jose C Del Rio, Ana Gutierrez, Jose Maria Barrasa, Angel T MartinezAbstract:Wood Extractives cause production troubles during pulp and paper manufacture. The potentiality of fungal strains for biotechnological removal of Extractives from Eucalyptus globulus Labill. Wood is...
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fungal degradation of lipophilic Extractives in eucalyptus globulus Wood
Applied and Environmental Microbiology, 1999Co-Authors: Ana Gutierrez, Jose C Del Rio, Maria Jesus Martinez, Angel T MartinezAbstract:Solid-state fermentation of eucalypt Wood with several fungal strains was investigated as a possible biological pretreatment for decreasing the content of compounds responsible for pitch deposition during Cl2-free manufacture of paper pulp. First, different pitch deposits were characterized by gas chromatography (GC) and GC-mass spectrometry (MS). The chemical species identified arose from lipophilic Wood Extractives that survived the pulping and bleaching processes. Second, a detailed GC-MS analysis of the lipophilic fraction after fungal treatment of Wood was carried out, and different degradation patterns were observed. The results showed that some basidiomycetes that decreased the lipophilic fraction also released significant amounts of polar Extractives, which were identified by thermochemolysis as originating from lignin depolymerization. Therefore, the abilities of fungi to control pitch should be evaluated after analysis of compounds involved in deposit formation and not simply by estimating the decrease in the total extractive content. In this way, Phlebia radiata, Funalia trogii, Bjerkandera adusta, and Poria subvermispora strains were identified as the most promising organisms for pitch biocontrol, since they degraded 75 to 100% of both free and esterified sterols, as well as other lipophilic components of the eucalypt Wood Extractives. Ophiostoma piliferum, a fungus used commercially for pitch control, hydrolyzed the sterol esters and triglycerides, but it did not appear to be suitable for eucalypt Wood treatment because it increased the content of free sitosterol, a major compound in pitch deposits.
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characterization of organic deposits produced in the kraft pulping of eucalyptus globulus Wood
Journal of Chromatography A, 1998Co-Authors: Jose C Del Rio, Ana Gutierrez, Francisco J Gonzalezvila, Francisco Martin, Javier RomeroAbstract:The composition of the organic deposits (the so-called pitch deposits) accumulated in different parts of the mills during the kraft pulping of Eucalyptus globulus Wood using an ECF (elementary chlorine free) bleaching sequence has been studied. Three pitch deposits were selected in the bleaching sequence. The first one was taken just after the kraft pulping and the oxygen prebleaching step, while the other two were taken from different parts of the mill after the chlorine dioxide bleaching step. The pitch deposits were Soxhlet extracted with acetone, and the extracts were redissolved in chloroform and subsequently analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The composition of E. globulus Wood Extractives was also analyzed for comparison. High temperature short capillary columns were used for the GC and GC-MS analyses, which enabled the elution and separation of compounds with a wide range of molecular mass, with no prior derivatization nor fractionation. Sterols and sterol esters were major compounds in the lipidic Extractives of E. globulus Wood, and hence, contribute to pitch deposition during pulping. The composition of the pitch deposits varied along the bleaching sequence. The kraft cooking and oxygen prebleaching had a minor influence on the composition of the extract of the pitch deposits. These extracts were very similar to those of E. globulus Wood Extractives, but with a higher content of waxes. No structural changes of sterols and sterol esters were observed. In contrast, after chlorine dioxide bleaching (ECF), the deposits were composed of saturated sterols and sterol esters, with the remarkable absence of unsaturated sterols and sterol esters, mainly the b-sitosterol and b-sitosterol esters, which were completely degraded. The insoluble residues left after acetone extraction of the pitch deposits were analyzed by Curie-point flash pyrolysis-GC-MS and by pyrolysis-methylation-GC-MS. Whereas conventional pyrolysis released series ofn-alkanes / n- alkenes, a series of fatty acid methyl esters were released after pyrolysis-methylation, suggesting that the residues left after acetone extraction might be made up of fatty acids salts. Very minor amounts of ellagic acid were also found in all the pitch deposits, probably deposited as magnesium complex. © 1998 Published by Elsevier Science B.V.
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analysis of lipophilic Extractives from Wood and pitch deposits by solid phase extraction and gas chromatography
Journal of Chromatography A, 1998Co-Authors: Ana Gutierrez, Jose C Del Rio, Francisco J Gonzalezvila, Francisco MartinAbstract:An analytical procedure for the analysis of lipophilic Extractives from Wood and pitch deposits is described in this paper. It comprises a rapid gas chromatographic method that enables the analysis of a high number of samples in a short period of time. Short-length, high-temperature capillary columns with thin films and high temperature- programming rates were preferred for the rapid analysis of Wood Extractives since they enable elution and separation of compounds within a wide molecular mass range (from fatty acids to sterol esters and triglycerides) in the same chromatographic analysis in a short period of time. Several examples of analysis of Extractives from pine and eucalypt Woods and pitch deposits in an eucalypt kraft pulp, are shown. On the other hand, a simple fractionation method using solid-phase extraction (SPE) in aminopropyl cartridges is described for the preparative scale separation and fractionation of Wood lipophilic Extractives into major lipid classes. The SPE advantages include smaller sample and solvent requirements and ease of use compared to conventional solvent extraction techniques.
Javier Romero - One of the best experts on this subject based on the ideXlab platform.
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lipophilic Extractives in process waters during manufacturing of totally chlorine free kraft pulp from eucalypt Wood
Chemosphere, 2001Co-Authors: Ana Gutierrez, Javier Romero, Jose C Del RioAbstract:The chemical composition of lipophilic Extractives from process waters throughout a totally chlorine free (TCF) bleaching sequence after kraft pulping of eucalypt Wood has been studied. These compounds are among the most problematic Wood constituents for both TCF and zero liquid effluent (ZLE) processes, since they tend to accumulate in circuits resulting in the formation of the so-called pitch deposits causing serious problems in the pulp and paper industry. Pitch deposits collected at different parts of the pulp mill were also characterized and their composition compared with that of lipophilic compounds in process waters and Eucalyptus globulus Wood. The identification of these compounds from process waters, Wood and pitch deposits was performed by gas chromatography and gas chromatography-mass spectrometry using short- and medium-length high temperature capillary columns. Sterols, sterol esters, steroid ketones and steroid hydrocarbons were the main compounds identified. These chemical species arise from eucalypt Wood Extractives that survive the pulping and are released from pulp into the process waters during the bleaching process. Finally, they can deposit in pulp and on different parts of the mill or remain suspended in process waters being discharged in effluents.
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lipophilic Extractives from eucalyptus globulus pulp during kraft cooking followed by tcf and ecf bleaching
Holzforschung, 2001Co-Authors: Ana Gutierrez, Javier RomeroAbstract:IntroductionWood resin, which consists of complex mixtures of differ-ent lipophilic Wood Extractives including fatty acids, resinacids, waxes, sterols, sterol esters and glycerides, causessignificant technical and economic troubles during pulp andpaper manufacturing (Sjostrom 1993). During Wood pulp-ing and refining of pulp, Extractives in the resin canals andray parenchyma cells can be released forming colloidalpitch. Pitch particles, which can be small in size, then coa-lesce into larger droplets which deposit on the surface offibers or equipment being responsible for production trou-bles and an increased incidence of quality defects (Hillisand Sumimoto 1989). In the production of bleached kraft pulp, a large part ofthe resin originally present in Wood is removed in the kraftcooking. However, the Wood Extractives remaining in thebrownstock pulp will be carried over to the bleach plantwhere they will react with the bleaching chemicals to vari-ous degrees depending on their chemical structure and onthe bleaching agent used (Jansson et al. 1995). The speciesthat survive the bleaching processes can be found as pulpExtractives and are detrimental for product quality. The newtrends to use environmentally-sound bleaching processessuch as “totally chlorine free” (TCF) in place of “elementalchlorine free” (ECF) sequences, are increasing the severityof pitch problems during kraft pulping of some types ofWood.Traditionally, pitch deposits in pulping and paper manu-facture have been reduced by debarking and seasoning logsand Wood chips and by adding physicochemical controlagents (Allen 1988; Dreisbach and Michalopoulos 1989;Allen et al. 1991). However, the cost is high and often theresults are far from satisfactory. As an alternative to theabove, biological removal of Wood Extractives by treatmentwith enzymes (Fischer and Messner 1992; Fujita et al.1992; Fischer et al. 1993) or microorganisms (Farrell et al.1993; Fischer et al. 1994; Gao et al. 1994; Behrendt andBlanchette 1997) has been suggested in recent years forpitch control. The biotechnological preparations commer-cially available are not effective for pitch control duringpulping of eucalypt Wood, which is extensively used as pulpraw material in Spain, Portugal, Brazil and other countries.This is because they are based on enzymes (such as lipasecommercialized by Novo Nordisk as Resinase
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characterization of organic deposits produced in the kraft pulping of eucalyptus globulus Wood
Journal of Chromatography A, 1998Co-Authors: Jose C Del Rio, Ana Gutierrez, Francisco J Gonzalezvila, Francisco Martin, Javier RomeroAbstract:The composition of the organic deposits (the so-called pitch deposits) accumulated in different parts of the mills during the kraft pulping of Eucalyptus globulus Wood using an ECF (elementary chlorine free) bleaching sequence has been studied. Three pitch deposits were selected in the bleaching sequence. The first one was taken just after the kraft pulping and the oxygen prebleaching step, while the other two were taken from different parts of the mill after the chlorine dioxide bleaching step. The pitch deposits were Soxhlet extracted with acetone, and the extracts were redissolved in chloroform and subsequently analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The composition of E. globulus Wood Extractives was also analyzed for comparison. High temperature short capillary columns were used for the GC and GC-MS analyses, which enabled the elution and separation of compounds with a wide range of molecular mass, with no prior derivatization nor fractionation. Sterols and sterol esters were major compounds in the lipidic Extractives of E. globulus Wood, and hence, contribute to pitch deposition during pulping. The composition of the pitch deposits varied along the bleaching sequence. The kraft cooking and oxygen prebleaching had a minor influence on the composition of the extract of the pitch deposits. These extracts were very similar to those of E. globulus Wood Extractives, but with a higher content of waxes. No structural changes of sterols and sterol esters were observed. In contrast, after chlorine dioxide bleaching (ECF), the deposits were composed of saturated sterols and sterol esters, with the remarkable absence of unsaturated sterols and sterol esters, mainly the b-sitosterol and b-sitosterol esters, which were completely degraded. The insoluble residues left after acetone extraction of the pitch deposits were analyzed by Curie-point flash pyrolysis-GC-MS and by pyrolysis-methylation-GC-MS. Whereas conventional pyrolysis released series ofn-alkanes / n- alkenes, a series of fatty acid methyl esters were released after pyrolysis-methylation, suggesting that the residues left after acetone extraction might be made up of fatty acids salts. Very minor amounts of ellagic acid were also found in all the pitch deposits, probably deposited as magnesium complex. © 1998 Published by Elsevier Science B.V.
Martina Meincken - One of the best experts on this subject based on the ideXlab platform.
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the effect of Wood Extractives on the thermal stability of different Wood lldpe composites
Thermochimica Acta, 2009Co-Authors: A N Shebani, A J Van Reenen, Martina MeinckenAbstract:The thermal stability of Wood polymer composites made with extractive-free Wood from four different Wood species was studied. Hot water (HW) Extractives, ethanol/cyclohexane (E/C) Extractives and both types of Extractives were eliminated from A. cyclops, E. grandis, P. radiata and Q. alba. Composites of LLDPE and 10 wt% of Wood were prepared, using poly vinyl alcohol-co-ethylene (EVOH) as a compatibilizer. The thermal degradation behavior of the composites was characterized with thermogravimetric analysis (TGA). The obtained results showed that in all cases, the degradation temperatures shifted to higher values after removal of the Extractives. The removal of E/C Extractives was less effective in its improvement of the thermal stability than the removal of HW Extractives. The largest improvement on the thermal stability of WPCs was achieved when both types of Extractives (E/C and HW) were removed.
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The effect of Wood Extractives on the thermal stability of different Wood species
Thermochimica Acta, 2008Co-Authors: A N Shebani, A J Van Reenen, Martina MeinckenAbstract:This study compares the thermal stability of different Wood species, which is an important factor for the production of Wood–polymer composites (WPCs), and investigates the effect of extraction on thermal properties. The chemical composition of four Wood species – Quercus alba, Pinus radiata, Eucalyptus grandis and Acacia cyclops – has been determined, as the species is expected to affect the thermal stability of Wood. Subsequently, the hot-water (HW) Extractives, ethanol/cyclohexane (E/C) Extractives and both Extractives were eliminated from the Wood via Soxhlet extraction and the thermal stability of the Wood determined with thermogravimetric analysis (TGA) under identical conditions. The results suggest that a higher cellulose and lignin content leads to better thermal stability of Wood in different temperature regimes. In all cases, the removal of Extractives improved the thermal stability of the Wood. The effect of combined extractions was more pronounced than of an individual extraction and E/C-extraction caused less improvement in the thermal stability of Wood than HW extraction. The degradation of the investigated Wood Extractives occurred at low rates over a broad temperature range. Pure cellulose exhibited superior thermal stability compared to Wood, but differences were observed between the investigated Wood species.
Pascal D Kamdem - One of the best experts on this subject based on the ideXlab platform.
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x ray photoelectron spectroscopy study of red oak quercus rubra black cherry prunus serotina and red pine pinus resinosa extracted Wood surfaces
Surface and Interface Analysis, 2005Co-Authors: Pascal Nzokou, Pascal D KamdemAbstract:The X-ray photoelectron spectroscopy (XPS) study of black cherry (Prunus serotina), red oak (Quercus rubra), and red pine (Pinus resinosa) Wood samples extracted with ethanol, ethanol—toluene, and water was conducted to evaluate chemical modifications occurring on the Wood surface due to Wood Extractives, and derive possible implications for Wood utilization. Results obtained indicate an increase in the O/C values following extraction treatments due to the partial removal of high carbon content Extractives. The C 1s peaks indicated a decrease in the area of the C1 peak, known to originate from lignin and Extractives following extraction. At the same time, a rise in the C2 peak (mainly originating from cellulose and hemicelluloses) was observed, indicating that more cellulose was exposed on the Wood surface following extraction. The O 1s peaks showed an increase in the O1 peak originating from cellulose, therefore confirming the trend observed for C 1s peaks. These results suggest that extracted Wood is more wettable because of the increased exposure of high-oxygen-content cellulose molecules, known to be more hydrophilic than lignin and high carbon content Extractives. Copyright © 2005 John Wiley & Sons, Ltd.
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influence of Wood Extractives on moisture sorption and wettability of red oak quercus rubra black cherry prunus serotina and red pine pinus resinosa
Wood and Fiber Science, 2004Co-Authors: Pascal Nzokou, Pascal D KamdemAbstract:Red oak ( Quercus rubra ), black cherry ( Prunus serotina ), and red pine ( Pinus resinosa ) Wood samples were soxhlet extracted with various combinations of organic solvents including ethanol, toluene, and water according to ASTM 1110-96, ASTM D1107-96, TAPPI T207 OM-88 and TAPPI T204 om-88 standards. Contact angle and sorption isotherms of extracted and unextracted specimens were determined to evaluate the role of Wood Extractives on the wettability and sorption properties of these Wood species. Extracted specimens adsorbed more water than unextracted specimens at high relative humidity in agreement with the literature. The contact angle decreased with increased extraction due to the removal of hydrophobic Extractives. However, the absorption rate of water, estimated as the decrease in contact angle over time suggests physical modification of the Wood surface by solvent extraction due to the migration and redistribution of hydrophobic Extractives.
