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Ganis Lukmandaru - One of the best experts on this subject based on the ideXlab platform.
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Correlation between Extractive Content and Colour Properties in Teak Heartwood
Jurnal Penelitian Hasil Hutan, 2016Co-Authors: Ganis LukmandaruAbstract:Beside for its high natural durability and resistancy of weather properties, teak ( T ectona g randis ) wood is also valued for its beautiful grain and colour. Theoretically, wood colour is highly affected by Extractive Content, particularly in the heartwood. Identification of correlation between wood colour and Extractive Content was determined through wood colour and Extractive measurements on the outer part of heartwood zone. The wood samples were collected from two locations of Perum Perhutani forest plantations, i.e. KPH Randublatung (35 trees, age class III-IV) and KPH Purwakarta (32 trees, age class VI). Samples were cut from bottom part of the trees and then ground into powder measuring of 40-60 mesh. The wood colour properties(CIE-L*a*b, CIE-L*C*h, CIE-X*Y*Z, Munsell Colour Chart and ISO Brightness) were then measured. Solubility of the teak wood Extractives were determined by extracting the powder in ethanol-benzene and hot water respectively. Results showed that the range of colour properties were L*= 40-62; a* = 3- 11; b* = 19-31; C* = 20-31; h 0 = 70-82; X= 10-25; Y= 8-23; Z=4-13; H=5-8; V =3-8; C =3-6; and W (ISO Brightness) = 4-12. Different sample location resulted in different trends of correlation between colour properties and Extractive Contents. No significant correlation was found between Extractive solubles in hot water and colour parameters. In general, the best correlations were encountered between brightness parameters from CIE-L*a*b* or ISO with ethanol- benzene Extractive Contents (r=- 0.54 or 0.50, respectively).
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VARIABILITY IN THE NATURAL TERMITE RESISTANCE OF PLANTATION TEAK WOOD AND ITS RELATIONS WITH WOOD Extractive Content AND COLOR PROPERTIES
Ministry of Environment and Forestry, 2011Co-Authors: Ganis LukmandaruAbstract:Property of natural termite resistance of teak (Tectona grandis)wood signifies one of its most important characteristics. With the purpose of understanding the variation in such resistance, four teak trees in the form of trunk (stem) from Randublatung , Central Java were randomly selected, and each wood portion sampled in radial and axial direction. Extractive Content and color properties of the teak wood were also measured and correlated with properties of its natural termite resistance. Bioassay test was conducted by no-choice feeding method using Reticulitermes speratus Kolbe termites. The Extractive Contents were determined by successive extraction using n-hexane, ethyl acetate, and methanol, respectively. Color properties were measured with the CIELAB system. Results showed that antitermitic activity of the teak wood was affected by radial and axial position in the corresponding tree. The wood from middle part of the trees in axial direction exhibited the most resistant to termites (mean mass loss = 1- 4 mg ), while in radial direction the sapwood exhibited the least resistance ( greatest mass loss), and moving inward to the near-pith heartwood the resistance tended to decrease somewhat (slight increase of mass loss). Heartwood and sapwood part differed significantly in ethyl acetate and methanol- soluble Extractive Contents. Apparently, the greater the ethyl-acetate-soluble Extractives (EEC) then the higher the termite resistant (lower mass loss), and conversely the greater the methanol- soluble Extractive (MEC) then the lower the termite resistant ( greater mass loss). The brightness index (L*) and redness index (a*) varied significantly in radial direction, however, no significant variation was found in color properties within the heartwood. No strong degree correlation was measured between the mass loss due to termite activity and Extractive Content parameters. In both heartwood and sapwood, a significant negative correlation (r = -0.50) was found between the mass loss and redness (a*), while correspondingly a significant positive correlation (r = +0.54) occurred between brightness and mass loss. These occurring phenomena strongly suggested that the red colored teak wood was brought about by the moderately polar EEC (e.g. tannin, quinone, and other polyphenol) that inflicted teak-wood resistance against termite (lower mass loss), while the bright-colored teak wood was due to the highly polar MEC (e.g sugar and other soluble carbohydrate) which were conversely responsible for lowering termite resistance ( greater mass loss)
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radial distribution of quinones in plantation teak tectona grandis l f
Annals of Forest Science, 2009Co-Authors: Ganis Lukmandaru, Koetsu TakahashiAbstract:Keywords: Tectona grandis / Extractives / tectoquinone / desoxylapachol / tree age Abstract • Quinones are primarily responsible for the natural durability of teak. • The previous paper in this series reported on the natural termite resistance of teak trees of different ages (8-, 30- and 51-year-old trees). In this study, the radial distribution of quinones (tectoquinone, lapachol, desoxylapachol and its isomer) and other components in the ethanol-benzene (1:2) extract were measured by means of gas chromatography. • Significant differences in desoxylapachol or its isomer Content were found among the outer heart- wood of 8-, 30- and 51-year old trees, as well as between the inner and outer parts of the heartwood. • All toxic quinone Contents were positively correlated with the total Extractive Content. The highest correlation degree was measured in the isodesoxylapachol Content. • Although linearly related, only modest correlations were observed between the natural termite re- sistance parameters and the Content of tectoquinone and isodesoxylapachol. Mots-cles : Tectona grandis / extractibles / tectoquinone / desoxylapachol / âge des arbres
Róger Moya - One of the best experts on this subject based on the ideXlab platform.
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Mineral Content in relation to radial position, altitude, chemical properties and density of Persian ironwood
Maderas-ciencia Y Tecnologia, 2015Co-Authors: Majid Kiaei, Ahmad Chehalmardian, Róger Moya, Behzad Kord, Mohammad FarsiAbstract:Persian ironwood (Parrotia persica) is native species from Iran and covers 10,54% of the commercial volume. Its wood structure and its chemical composition are affected by growth conditions. The aim of the study was to assess the variation of mineral Content (Ni, Fe, Cu, Zn, Pb, Cd), wood density and chemical properties (cellulose, lignin, ash and Extractive) of ironwood in relation to altitude above sea level (100, 500 and 700 meter) and pith distance within stem (near to pith and bark and middle point). In addition was investigate the relationship between mineral Content with oven-dried density and chemical properties. Results showed that Cd, Cu, Fe, Ni and Zn Content (except Pb concentration) increased by increasing of altitude and decreased along radial position within stem from the pith to the bark. Lignin, ash and Extractive Content increased by increasing altitudes from 100 to 700 meter while cellulose decreased. Radial position had not significant impact on the chemical properties. There are significant relationships between mineral Content–chemical properties and between mineral Content-wood density (except Cu - density). Forward stepwise regression showed that ash and lignin Content had important role on the variation of all of mineral Content except on Cd.
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a review of heartwood properties of tectona grandis trees from fast growth plantations
Wood Science and Technology, 2014Co-Authors: Róger Moya, Brian Bond, Henry QuesadaAbstract:Teak (Tectona grandis L. f) has been introduced to reforestation programs in many tropical countries for timber production. The use of teak plantations has changed the supply from large-diameter logs to small-diameter logs featuring a higher proportion of juvenile wood and more knots. Generally, the teak from fast-growth plantation is harvested after 15–30 years of growth, with logs ranging from 12 to 30 cm in diameter. The goal of this work was to review the factors that influence the heartwood formation, variation, quality, color, and durability in teak and to understand which factors should be controlled in fast-growth plantations. Important factors in the heartwood properties of teak trees from fast-growth plantations are as follows: the tree age, longitudinal variation, geographic location, environmental conditions, and silvicultural activities. These factors influence heartwood Extractive Content, color variation, and durability.
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relationship between wood color parameters measured by the cielab system and Extractive and phenol Content in acacia mangium and vochysia guatemalensis from fast growth plantations
Molecules, 2012Co-Authors: Róger Moya, Roy Mario Soto Fallas, Pablo Jimenez Bonilla, Carolina TenorioAbstract:The heterogeneity of color distribution between sapwood and heartwood limits the market for wood from fast-growth plantations of tropical species. Wood color is associated with wood Extractives Contents. This study presents the relationship between wood color parameters measured by the CIELab color system and total amount of Extractives and phenolic-type Extractives in ethanol-toluene and hot water extracts of wood from two fast-growth plantation species. The results demonstrated that the difference in sapwood and hardwood color in Vochysia guatemalensis and Acacia mangium is caused by lower concentrations of Extractives in sapwood of both species. Additionally, variations in total Extractive and phenolic Content have different effects on the color parameters (L*, a* and b*) of both species studied. In Vochysia guatemalensis wood, parameter L* decreases as total Extractive and phenolic Content increases; however, parameter a* increases as the Content of Extractives and phenols increases. In Acacia mangium, the amount of phenols showed no relationship with the color parameters. The ethanol-toluene total Extractive Content, however, shows a relationship with several color parameters. An increase in the Content of total Extractives in water and ethanol-toluene increases parameter a*, but decreases parameter L*.
Rupert Wimmer - One of the best experts on this subject based on the ideXlab platform.
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Dependence of colour and discolouration on total Extractive Content of African Padauk and Jatoba
Wood Science and Technology, 2014Co-Authors: Jan Baar, Rupert Wimmer, Stefano D’amicoAbstract:This study is about relationships between total Extractive Contents, heartwood colour and light-induced discolourations of the tropical species African Padauk ( Pterocarpus soyauxii Taub) and Jatoba ( Hymenaea courbaril L.). Wood surface colour was measured spectrophotometrically before and after light irradiation. Subsequently, the total Extractive Content was determined and linked to the colour parameters. Total Extractive Content varied between 6 % (Jatoba) and 27 % (African Padauk). The fact that non-irradiated Jatoba appeared lighter and more yellow with higher Extractives Contents, opposed the often assumed relationship that more heartwood Extractives cause darker wood. For light-irradiated Jatoba wood only the reddishness was more intense when samples had higher Extractive Content. In contrast, light-irradiated African Padauk showed significant differences in all colour parameters as Extractives varied. High overall colour change in African Padauk due to light irradiation was observed; however, no relationship with the Extractive Content existed. In contrast, discolouration rate of Jatoba wood strongly varied with its Extractive Content. Individual wood species react differently during exposure to light and therefore require specific surface treatment to maintain the desired colour appearance and colour stability.
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EFFECTS OF HEARTWOOD ExtractiveS ON MECHANICAL PROPERTIES OF LARCH
IAWA Journal, 2005Co-Authors: Michael Grabner, Ulrich Müller, Notburga Gierlinger, Rupert WimmerAbstract:The genus Larix is exceptional for its high Content of Extractives in the heartwood, with the dominant component arabinogalactan found abundantly in cell lumens of tracheids. On parallel samples prepared from 20 European, Japanese and hybrid larch trees (Larix decidua Mill., L. kaempferi Carr., and L. decidua × L. kaempferi, respectively) Extractive Contents and mechanical parameters were measured. The hot-water Extractives in the heartwood had a significant effect on transversal compression strength and Young's Modulus. In heartwood, increasing Extractive Content went hand-in-hand with better mechanical properties in the transverse direction. The extraction procedure led to negligible changes in the sapwood. Anatomically the Extractive-filled tracheids showed a tendency of being arranged radially, closely to wood rays. The Extractive arabinogalactan in larch heartwood has multiple effects on different aspects of wood quality, among which is lateral mechanical enforcement.
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Heartwood Extractives and lignin Content of different larch species (Larix sp.) and relationships to brown-rot decay-resistance
Trees - Structure and Function, 2004Co-Authors: Notburga Gierlinger, Rupert Wimmer, Dominique Jacques, Manfred Schwanninger, Luc PâquesAbstract:The Extractive Content of lignin and the brown-rot decay-resistance against Coniophora puteana and Poria placenta were studied in larch heartwood from different species and origin (Larix decidua var. decidua, L. decidua var. sudetica, L. kaempferi , L. × eurolepis). The study material consisted of 106 trees from a 39-year old provenance trial in France. The hot-water-soluble Extractives were very variable (from5.66% to 20.50% of dry weight), but there was no significant variation between the investigated species and origins. In contrast, acetone Extractives, the total amount of phenolics and lignin showed significant differences. The concentration of phenolics and lignin was significantly higher in L. kaempferi and in L. × eurolepis than in L. decidua. The total phenolics Content was strongly correlated with decay-resistance in all investigated larch origins. A higher concentration of phenolics goes hand in hand with higher decay resistance and phenolics might therefore be a promising parameter to rapidly evaluate the level of decay-resistance in larch.
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impregnation of softwood cell walls with melamine formaldehyde resin
Bioresource Technology, 2003Co-Authors: Wolfgang Gindl, F Zargaryaghubi, Rupert WimmerAbstract:Melamine-formaldehyde (MF) resin impregnation has shown considerable potential to improve a number of wood properties, such as surface hardness and weathering resistance. In this study, selected factors influencing the uptake of MF resin into the cell wall of softwood were studied. Using UV-microspectroscopy, it could be shown that water soluble MF diffused well into the secondary cell wall and the middle lamella. Concentrations as high as 24% (v/v) were achieved after an impregnation of 20 h. High cell wall moisture Content, high water Content of the resin used for impregnation, and low Extractive Content are factors which are favourable for MF resin uptake into the cell wall. For dry cell walls, solvent exchange drying improved resin uptake to a similar extent, as was the case when cell walls were soaked in water.
Beatriz O. Saidman - One of the best experts on this subject based on the ideXlab platform.
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Durability of five native Argentine wood species of the genera Prosopis and Acacia decayed by rot fungi and its relationship with Extractive Content.
Biodegradation, 2010Co-Authors: Carolina Luciana Pometti, Sabrina Palanti, Benedetto Pizzo, Jean Paul Charpentier, Nathalie Boizot, Claudio Resio, Beatriz O. SaidmanAbstract:The natural durability of four Argentinean species of Prosopis and one of Acacia was evaluated in laboratory tests, according to European standards, using three brown rot and one white rot fungi. These tests were complemented by assessing the wood chemical composition. All the species were from moderately slightly durable to very durable (classes 4–1), and in all cases the heartwood was the most resistant to fungal attack. Chemical Extractives Content (organic, aqueous, tannic and phenolic) was higher in the heartwood. However, species durability was not related to Extractive Contents nor with wood density. Instead, it is possible that Extractives could contribute to natural durability in different ways, including the effects related to the antioxidant properties of some of them.
Nadine Amusant - One of the best experts on this subject based on the ideXlab platform.
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Diversity of decay resistance strategies of durable tropical woods species: Bocoa prouacencsis Aublet, Vouacapoua americana Aublet, Inga alba (Sw.) Wild
International Biodeterioration and Biodegradation, 2014Co-Authors: Nadine Amusant, M Nigg, Bernard Thibaut, Jacques BeauchêneAbstract: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.
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Influence of soil properties on the natural durability, Extractive Content and colour of teak (Tectona grandis L.f.) wood in Togo
2010Co-Authors: Adzo Dzifa Kokutse, Nadine Amusant, Nabila Boutahar, Gilles ChaixAbstract:Togolese teak is highly resistant to pathogen attack, but natural durability and wood colour vary according to plantation sites and geographical zones. Therefore, further information concerning the influence of environmental parameters and their effects on teak wood quality is necessary and it could be possible to improve these characteristics through tree breeding and silviculture programs in Togo. In order to examine the influence of soil properties on teak wood characteristics, 321 wood samples issued from 20 trees were exposed to two fungi: Antrodia sp., and Coriolus versicolor. Depending on type of soil in which they grew, trees had been randomly. selected in two different sites in the same climatic area in Togo. The colour parameters of each sample were measured using the CIELAB system and total Extractive Content was determined using the Accelerated Solvent Extraction (ASE) procedure. Results showed a . significantly lower total Extractive Content (11.1%) for trees that grew on hydromorphic tropical ferruginous (HTF) sail than trees from drained ferruginous soil (12.8%). Samples from RTF soil were lighter and the redness a* andyellow-blueness b* were significantly higher. Independently of soil quality, aIl the trees were highly durable regarding decay by C. versicolor. With Antrodia sp., 90 % of the trees from both sites were highly durable and only 10% were durable. However, samples from HTF soiI were less durable with regard to the two fimgi. (Resume d'auteur)
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Soil property effects on the natural durability, Extractive Content and colour of teak (Tectona grandis L.f) wood in Togo
2009Co-Authors: Adzo Dzifa Kokutse, Nadine Amusant, Nabila Boutahar, Gilles ChaixAbstract:Togolese teak is highly resistant to pathogen attack, but natural durability and wood colour vary according to plantation sites and geographical zones. Therefore, further information concerning the influence of environmental parameters and their effects on teak wood quality is necessary and it could be possible to improve these characteristics through tree breeding and silviculture programs in Togo. In order to examine the influence of soil properties on teak wood characteristics, 321 wood samples issued from 20 trees were exposed to two fungi: #Antrodia sp#., and #Coriolus versicolor#. Depending on type of soil in which they grew, trees had been randomly selected in two different sites in the same climatic area in Togo. The colour parameters of each sample were measured using the CIELAB system and total Extractive Content was determined using the Accelerated Solvent Extraction (ASE) procedure. Results showed a significantly lower total Extractive Content (11.1%) for trees that grew on hydromorphic tropical ferruginous (HTF) soil than trees from drained ferruginous soil (12.8%). Samples from HTF soil were lighter and the redness a* and yellow-blueness b* were significantly higher. Independently of soil quality, all the trees were highly durable regarding decay by #C. versicolor#. With #Antrodia sp#., 90 % of the trees from both sites were highly durable and only 10% were durable. However, samples from HTF soil were less durable with regard to the two fungi. (Resume d'auteur)
