Microdistribution of copper in copper-ethanolamine (Cu-EA) treated southern yellow pine (Pinus spp.) related to density distribution

Holzforschung ◽  
2005 ◽  
Vol 59 (1) ◽  
pp. 82-89 ◽  
Author(s):  
Jinzhen Cao ◽  
D. Pascal Kamdem
Keyword(s):  
Cell Wall ◽  
Density Distribution ◽  
Cell Walls ◽  
Middle Lamella ◽  
Treated Wood ◽  
Yellow Pine ◽  
Using Data ◽  
Pinus Spp ◽  
Southern Yellow Pine ◽  
The Relationship

Abstract The relationship between copper absorption and density distribution in wood cell walls was investigated in this study. The density distribution on layer level was obtained from two approaches: (1) calculation by using data obtained from literature; (2) microdistribution of carbon and oxygen atoms in the wood cell. The microdistribution of carbon and oxygen in untreated southern yellow pine (Pinus spp.) sapwood, as well as copper in cell walls of copper-ethanolamine (Cu-EA) treated wood was determined by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDXA). Both approaches for density distribution led to the same result: the density was higher in the compound middle lamella and cell corners than in the secondary wall. The concentration/intensity of Cu, C and O in the cell wall follow the same trend as the density distribution; suggesting that density may play a major role in SEM-EDXA study of the distribution of metal-containing wood preservatives within the wood cell wall.

Moisture adsorption characteristics of copper-ethanolamine (Cu-EA) treated Southern yellow pine (Pinus spp.)

Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 32-38 ◽  
Author(s):  
J. Cao ◽  
D. P. Kamdem
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Moisture Content ◽  
Treated Wood ◽  
Untreated Wood ◽  
Moisture Adsorption ◽  
Adsorption Sites ◽  
Yellow Pine ◽  
Pinus Spp ◽  
Southern Yellow Pine

Abstract Moisture adsorption isotherms were determined for untreated and copper-ethanolamine (Cu-EA) treated wood at different copper retention levels. The Cu-EA treatment reduces the water vapor accessibility in wood because copper has occupied some of the adsorption sites for moisture during the treatment. The percentage of adsorption sites occupied by copper was evaluated by M t/M u, which is the ratio of equilibrium moisture content for treated wood to untreated wood. The results show that, within the copper retention range used in this study, the M t/M u value decreases linearly at lower temperatures (4 and 15 °C) or logarithmically at higher temperatures (30 and 40 °C) with the increase of copper retention, suggesting that the percentage of adsorption sites occupied by copper (P) increases linearly or logarithmically with the copper retention in Cu-EA treated wood. P decreases with the increase of relative humidity. The reason is that more adsorption sites become available for moisture at higher relative humidity. It has also been found that the influence of Cu-EA treatment on hydrated water (M h) is more significant than that on dissolved water (M s).

Silicification of wood-cell walls

1994 ◽  
Vol 52 ◽  
pp. 428-429
Author(s):  
S. E. Keckler ◽  
D. M. Dabbs ◽  
N. Yao ◽  
I. A. Aksay
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Cell Walls ◽  
Lignin Content ◽  
Resin Composite ◽  
Middle Lamella ◽  
Cellulose Fibers ◽  
Complex Structures ◽  
Rich Region ◽  
Inorganic Precursors

Cellular organic structures such as wood can be used as scaffolds for the synthesis of complex structures of organic/ceramic nanocomposites. The wood cell is a fiber-reinforced resin composite of cellulose fibers in a lignin matrix. A single cell wall, containing several layers of different fiber orientations and lignin content, is separated from its neighboring wall by the middle lamella, a lignin-rich region. In order to achieve total mineralization, deposition on and in the cell wall must be achieved. Geological fossilization of wood occurs as permineralization (filling the void spaces with mineral) and petrifaction (mineralizing the cell wall as the organic component decays) through infiltration of wood with inorganics after growth. Conversely, living plants can incorporate inorganics into their cells and in some cases into the cell walls during growth. In a recent study, we mimicked geological fossilization by infiltrating inorganic precursors into wood cells in order to enhance the properties of wood. In the current work, we use electron microscopy to examine the structure of silica formed in the cell walls after infiltration of tetraethoxysilane (TEOS).

The Effect of Variables on Laboratory Termite Testing: Part 4—Test Block Species, Size, and Test Photoperiod

2021 ◽  
Vol 71 (2) ◽  
pp. 95-100
Author(s):  
G. B. Lindsey ◽  
T. L. Amburgey ◽  
H. M. Barnes
Keyword(s):  
Native Species ◽  
Wood Sample ◽  
Treated Wood ◽  
Reticulitermes Flavipes ◽  
Coptotermes Formosanus ◽  
Standard Laboratory ◽  
Yellow Pine ◽  
Southern Yellow Pine ◽  
The Impact ◽  
Standard Tests

Abstract The objective of this study was to determine the impact on termite feeding of wood sample size and species and test photoperiod in standard tests. Native species (Reticulitermes flavipes) and introduced species (Coptotermes formosanus) were tested in an American Wood-Preservers' Association E1 standard laboratory test. For testing involving treated wood, southern yellow pine was determined to be preferable to spruce based on its treatability and availability. Test blocks of 25 by 25 by 6 mm were deemed adequate for testing, with large blocks presenting difficulty with retrieval of termites to determine mortality and smaller blocks being consumed too rapidly by the termites in the test. Photoperiod comparisons were not significantly different for R. flavipes; however, C. formosanus indicated a preference for 100 percent darkness. Therefore, the recommendation is to maintain tests using each species in a 100 percent dark environment.

Relationship of wood cell wall ultrastructure to bacterial degradation of wood

IAWA Journal ◽  
2019 ◽  
Vol 40 (4) ◽  
pp. 845-870 ◽  
Author(s):  
Adya P. Singh ◽  
Yoon Soo Kim ◽  
Ramesh R. Chavan
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Wood Cell Wall ◽  
Bacterial Degradation ◽  
Cell Wall Components ◽  
Degrading Bacteria ◽  
Wall Ultrastructure ◽  
Relationship Of ◽  
The Relationship ◽  
Wall Components

ABSTRACT This review presents information on the relationship of ultrastructure and composition of wood cell walls, in order to understand how wood degrading bacteria utilise cell wall components for their nutrition. A brief outline of the structure and composition of plant cell walls and the degradation patterns associated with bacterial degradation of wood cell walls precedes the description of the relationship of cell wall micro- and ultrastructure to bacterial degradation of the cell wall. The main topics covered are cell wall structure and composition, patterns of cell wall degradation by erosion and tunnelling bacteria, and the relationship of cell wall ultrastructure and composition to wood degradation by erosion and tunnelling bacteria. Finally, pertinent information from select recent studies employing molecular approaches to identify bacteria which can degrade lignin and other wood cell wall components is presented, and prospects for future investigations on wood degrading bacteria are explored.

Ultrastructural Changes in the Cell Walls of Cambial Derivatives During Wood Formation in Indian ELM (Holoptelea Integrifolia)

IAWA Journal ◽  
2012 ◽  
Vol 33 (4) ◽  
pp. 403-416 ◽  
Author(s):  
Karumanchi S. Rao ◽  
Yoon Soo Kim ◽  
Pramod Sivan
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Middle Lamella ◽  
Ultrastructural Changes ◽  
Cell Wall Polysaccharides ◽  
Lignin Distribution ◽  
Parenchyma Cells ◽  
Ray Cells ◽  
Xylem Elements ◽  
S2 Layer

Sequential changes occurring in cell walls during expansion, secondary wall (SW) deposition and lignification have been studied in the differentiating xylem elements of Holoptelea integrifolia using transmission electron microscopy. The PATAg staining revealed that loosening of the cell wall starts at the cell corner middle lamella (CCML) and spreads to radial and tangential walls in the zone of cell expansion (EZ). Lignification started at the CCML region between vessels and associated parenchyma during the final stages of S2 layer formation. The S2 layer in the vessel appeared as two sublayers,an inner one and outer one.The contact ray cells showed SW deposition soon after axial paratracheal parenchyma had completed it, whereas noncontact ray cells underwent SW deposition and lignification following apotracheal parenchyma cells. The paratracheal and apotracheal parenchyma cells differed noticeably in terms of proportion of SW layers and lignin distribution pattern. Fibres were found to be the last xylem elements to complete SW deposition and lignification with differential polymerization of cell wall polysaccharides. It appears that the SW deposition started much earlier in the middle region of the fibres while their tips were still undergoing elongation. In homogeneous lignin distribution was noticed in the CCML region of fibres.

scholarly journals Domain-specific and cell type-specific localization of two types of cell wall matrix polysaccharides in the clover root tip.

1992 ◽  
Vol 118 (2) ◽  
pp. 467-479 ◽  
Author(s):  
M A Lynch ◽  
L A Staehelin
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Cellular Differentiation ◽  
Cortical Cell ◽  
Middle Lamella ◽  
Root Cap ◽  
Root Tip ◽  
Cortical Cells ◽  
Peripheral Cell ◽  
Clover Root

Using immunocytochemical techniques and antibodies that specifically recognize xyloglucan (anti-XG), polygalacturonic acid/rhamnogalacturonan I (anti-PGA/RG-I), and methylesterified pectins (JIM 7), we have shown that these polysaccharides are differentially synthesized and localized during cell development and differentiation in the clover root tip. In cortical cells XG epitopes are present at a threefold greater density in the newly formed cross walls than in the older longitudinal walls, and PGA/RG-I epitopes are detected solely in the expanded middle lamella of cortical cell corners, even after pretreatment of sections with pectinmethylesterase to uncover masked epitopes. These results suggest that in cortical cells XG and PGA/RG-I are differentially localized not only to particular wall domains, but also to particular cell walls. In contrast to their nonoverlapping distribution in cortical cells, XG epitopes and PGA/RG-I epitopes largely colocalize in the epidermal cell walls. The results also demonstrate that the middle lamella of the longitudinal walls shared by epidermal cells and by epidermal and cortical cells constitutes a barrier to the diffusion of cell wall and mucilage molecules. Synthesis of XG and PGA/RG-I epitope-containing polysaccharides also varies during cellular differentiation in the root cap. The differentiation of gravitropic columella cells into mucilage-secreting peripheral cells is marked by a dramatic increase in the synthesis and secretion of molecules containing XG and PGA/RG-I epitopes. In contrast, JIM 7 epitopes are present at abundant levels in columella cell walls, but are not detectable in peripheral cell walls or in secreted mucilage. There were also changes in the cisternal labeling of the Golgi stacks during cellular differentiation in the root tip. Whereas PGA/RG-I epitopes are detected primarily in cis- and medial Golgi cisternae in cortical cells (Moore, P. J., K. M. M. Swords, M. A. Lynch, and L. A. Staehelin. 1991. J. Cell Biol. 112:589-602), they are localized predominantly in the trans-Golgi cisternae and the trans-Golgi network in epidermal and peripheral root cap cells. These observations suggest that during cellular differentiation the plant Golgi apparatus can be both structurally and functionally reorganized.

Ultrastructure des parois de cerises Bigarreau Burlat de textures différentes au cours de la maturation

1996 ◽  
Vol 74 (12) ◽  
pp. 1974-1981 ◽  
Author(s):  
C. Batisse ◽  
P. J. Coulomb ◽  
C. Coulomb ◽  
M. Buret
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Middle Lamella ◽  
Primary Cell ◽  
Wall Material ◽  
Cell Wall Degradation ◽  
Composition And Structure ◽  
Cell Wall Texture ◽  
Synthesis And Degradation ◽  
Soft Fruits

The changes in texture of fruits during ripening are linked to cell wall degradation involving synthesis and degradation of polymers. An increase in pectin solubility leads to cell sliding and an elastic aspect of tissues. The biochemical cell wall process differs between soft and crisp fruits originating from a same cultivar but cultivated under different agroclimatic conditions. Although the proportions of cell wall material are similar, the composition and structure of the two cell walls are very different at maturity. A solubilization of the middle lamella and a restructuration of the primary cell walls arising from the cells separation is observed in crisp fruits. In contrast, the middle lamella of the soft fruits is better preserved and the primary cell walls are thin and show degradation bags delimited by residual membrane formations. In addition, the macroendocytosis process by endosome individualization is more important in soft fruits. In conclusion, the fruit texture depends on the extent of the links between cell wall polymers. Keywords: cherry, cell wall, texture, ultrastructural study.

Ion behaviour in plant cell walls. IV. Selective cation binding by Sphagnum russowii cell walls

1990 ◽  
Vol 68 (4) ◽  
pp. 773-781 ◽  
Author(s):  
Conrad Richter ◽  
Jack Dainty
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Divalent Cations ◽  
Selectivity Coefficient ◽  
Weak Acid ◽  
Small Population ◽  
Cation Binding ◽  
Trivalent Cations ◽  
Using Data ◽  
A Site

Selective cation binding by Sphagnum russowii cell walls was investigated using data from bicationic potentiometric titrations of isolated cell walls. Selectivity measurements were interpreted in the context of Manning condensation. In titrations with cations of different valency, selectivity favoured the higher valency cation, as expected in Manning condensation. This selectivity generally increased with bathing pH until the wall-bound polyuronic acids became fully ionized (pH > 5). The selectivity coefficient order at full ionization was Na+–Ca2+ > Na+–La3+ > Ca2+–La3+, as predicted by the weak acid Donnan–Manning (WADM) model. Other phenomena also appear to influence binding selectivity. A small population of isolated binding sites are more effectively neutralized by univalent (or divalent) than divalent (or trivalent) cations. High selectivity for cations of lower valency at low pH also suggests a site isolation effect. In bicationic titrations involving divalent cations only, Sr24+ and Ca2+ were bound by the cell wall with approximately equal effectiveness, as predicted by the WADM model. However, cation or binding site specificities probably account for the favoured binding of Ca2+ over Mg2+ by the cell wall. Key words: ion exchange, cell wall, selectivity.

The fate of acetyl groups and sugar components during the digestion of grass cell walls in sheep

1977 ◽  
Vol 89 (2) ◽  
pp. 327-340 ◽  
Author(s):  
E. Jane Morris ◽  
J. S. D. Bacon
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Lignin Content ◽  
Sodium Ethoxide ◽  
Mesophyll Cell ◽  
Cell Types ◽  
Gas Liquid Chromatography ◽  
Cell Wall Preparation ◽  
The Relationship ◽  
Isolated Cell

SummaryThe digestibilities of grass cell wall constituents determined in a digestion trial were compared with those obtained by suspending various isolated cell wall preparations in nylon bags in the rumen of a sheep. Particular attention was paid to acetyl groups and to individual sugars, which were determined in both cases by gas liquid chromatography.For dried grass and hay in the digestion trial the cell wall constituents showed digestibilities decreasing in the following order: arabinose, galactose, glucose, xylose, acetyl, lignin.For a leaf cell wall preparation derived from all cell types except mesophyll, the nylon bag technique allowed the same order of digestibilities; rhamnose and uronic acids were also measured and found to be rapidly digested. Mesophyll cell walls placed in nylon bags were more readily digested than non-mesophyll. All the sugars, and also acetyl groups, were digested to the same extent.In a grass cell wall preparation isolated from sheep faeces, tested similarly, xylose and glucose were digested to the same extent, but acetyl groups were less digested.Removal of acetyl groups, using sodium ethoxide, which left the sugar composition and lignin content unchanged, increased the digestibility particularly of the cell walls from faeces.The results are discussed with reference to the relationship between cell wall composition and digestibility.

Sign in / Sign up

Export Citation Format

Share Document