The Effect of Varying Latewood Proportion on the Radial Distribution of Lignin Content in a Pine Stem

Holzforschung ◽  
2001 ◽  
Vol 55 (5) ◽  
pp. 455-458 ◽  
Author(s):  
W. Gindl
Keyword(s):  
Radial Distribution ◽  
Secondary Wall ◽  
Lignin Content ◽  
Middle Lamella ◽  
Individual Growth ◽  
Juvenile Growth ◽  
Growth Rings ◽  
Strong Negative Correlation ◽  
Compound Middle Lamella ◽  
The Difference

Summary The radial distribution of lignin content in a pine stem was compared to latewood proportion. With the exception of the innermost juvenile growth rings, a strong negative correlation was found. However, the cell-wall lignin content of low lignin growth rings was equal to that of high-lignin growth rings. Therefore, the difference in lignin content between individual growth rings was solely due to varying ratios of high-lignin compound middle lamella to low-lignin secondary wall in thin- and thick-walled tracheids.

Inhomogeneities in the Chemical Structure of Hardwood Lignins

Holzforschung ◽  
2003 ◽  
Vol 57 (3) ◽  
pp. 255-265 ◽  
Author(s):  
H. Önnerud ◽  
G. Gellerstedt
Keyword(s):  
Secondary Wall ◽  
Lignin Content ◽  
Middle Lamella ◽  
Size Exclusion ◽  
Wall Material ◽  
Thermomechanical Pulp ◽  
Aryl Ether ◽  
Spruce Wood ◽  
Exclusion Chromatography ◽  
The Difference

Summary Bauer-McNett fractions of an aspen chemi-thermomechanical pulp showed a significant variation with respect to lignin content and sugar composition, and two of the fractions were found to be particularly rich in middle lamella and secondary wall material, respectively. The secondary wall lignin of aspen was found to contain larger amounts of non-condensed β-O-4 aryl ether structures than the middle lamella lignin and the difference was attributed to a larger amount of syringyl structures as revealed by thioacidolysis. Size exclusion chromatography of the thioacidolysis products from birch and spruce wood showed a larger part of lignin oligomers being present in the degraded spruce lignin. Moreover, birch lignin had a lower phenolic content than both aspen and spruce lignin. Thioacidolysis followed by Raney-nickel desulphuration was used for the analysis of hardwood lignin trimers.

Characterisation of compound middle lamella isolated by a combination of wet-beating, sedimentation, and methanol dialysis

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yasuyuki Matsushita ◽  
Taichi Fukumura ◽  
Dan Aoki ◽  
Kazuhiko Fukushima
Keyword(s):  
Secondary Wall ◽  
Lignin Content ◽  
Middle Lamella ◽  
Natural State ◽  
Cellulose Content ◽  
Nmr Analysis ◽  
Sem Images ◽  
Simple Method ◽  
Compound Middle Lamella ◽  
C Nmr

Abstract A simple method was developed to isolate the compound middle lamella (CML) in its natural state using wet-beating, sedimentation, and methanol dialysis. The isolated CML fraction was characterised. The CML was isolated in 2.0% yield from the mature wood of Ginkgo biloba. Scanning electron microscopy (SEM) images of the isolated CML fraction showed the presence of flake-like structures. However, some small amounts of secondary wall substance was observed. The lignin content of the CML fraction was approximately 45%. Thioacidolysis reactions with the isolated CML fraction revealed that the lignin β-O-4 structure was scarce in the isolated fraction and that numerous structures with two or more consecutive condensed-type bonds were present. Results from the solid-state carbon-13 nuclear magnetic resonance (13C NMR) experiments indicated that the CML fraction had low crystallinity, indicating low cellulose content. Liquid-state NMR analysis of the lignin from the CML fraction revealed the absence of p-hydroxyphenyl (H) units.

A Topocuemical and Semiquantitative Study of The Lignification During Ageing of Bamboo Culms (Phyllostachys Viridiglaucescens)

IAWA Journal ◽  
2005 ◽  
Vol 26 (1) ◽  
pp. 99-110 ◽  
Author(s):  
Bieke Lybeer ◽  
Gerald Koch
Keyword(s):  
Lignin Content ◽  
Middle Lamella ◽  
First Year ◽  
Vascular Bundles ◽  
Compound Middle Lamella ◽  
Parenchyma Cells ◽  
Early Maturing ◽  
Increasing Trend ◽  
Ferulic Acids ◽  
Acid Esters

The lignification of Phyllostachys viridiglaucescens (Carr.) Riv. & Riv. during ageing was studied topochemically by means of UV microspectrophotometry. The study revealed that p-coumaric and ferulic acids are widely distributed in P. viridiglaucescens and that their content is dependent on the anatomicallocation and the differentiation phase. The lignin in the epidermal cell wall is deposited early in the development and does not increase with age. This is in contrast with the fibres and the ground parenchyma cells where an increasing trend in lignification during the first year is shown. The early maturing fibres of the vascular bundles reveal a maximum absorbance value at 280 nm (guaiacyl peak) whereas the late maturing fibres displaya shoulder at 310-320 nm in young culms and a guaiacyl peak in older culms. The S2 fibre wall has a lamellar structure with an increasing lignin content from the centre towards the compound middle lamella. The compound middle lamellae show higher absorbance values and are richer in p-coumaric and ferulic acid esters in comparison to the S2 wall layers. The vessel walls have a low lignin content.

Topochemical Investigations on Delignification of Picea abies [L.] Karst. during Alkaline Sulfite (ASA) and Bisulfite Pulping by Scanning UV Microspectrophotometry

Holzforschung ◽  
2003 ◽  
Vol 57 (6) ◽  
pp. 611-618 ◽  
Author(s):  
G. Koch ◽  
B. Rose ◽  
R. Patt ◽  
O. Kordsachia.
Keyword(s):  
Picea Abies ◽  
Cell Walls ◽  
Lignin Content ◽  
Middle Lamella ◽  
Cellular Level ◽  
Analytical Technique ◽  
Compound Middle Lamella ◽  
Lignin Removal ◽  
S2 Layer ◽  
Uv Microspectrophotometry

Summary Delignification of spruce (Picea abies [L.] Karst.) during ASA (modified alkaline sulfite/anthraquinone pulping with alkali splitting) and magnesium bisulfite pulping was studied on a cellular level using scanning UV microspectrophotometry. This improved cellular analytical technique enables direct imaging of the topochemistry of lignin removal within the cell wall at different stages of cooking. The cooks were performed in a laboratory digester with forced liquor circulation. At 30 min intervals samples were taken for chemical and UV microscopic analyses. UV microscopy reveals that delignification during ASA pulping starts in the region of the pit canals and proceeds evenly across the entire S2 layer. As a specific feature of bisulfite pulping, a partial delignification of the radial compound middle lamella can be detected after 60 min of cooking. After 120 min, in both processes, the delignified cell walls show low UV absorbance values of both S2 and compound middle lamella. At this stage, approximately 90% of the initial lignin content is removed. At the end of both pulping processes, only parts of the cell corners can be distinguished by the new UV scanning technique.

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).

Mechanical Properties of Secondary Wall and Compound Corner Middle Lamella near the Phenol-Formaldehyde (PF) Adhesive Bond Line Measured by Nanoindentation

2011 ◽  
Vol 236-238 ◽  
pp. 1746-1751 ◽  
Author(s):  
Kun Liang ◽  
Guan Ben Du ◽  
Omid Hosseinaei ◽  
Si Qun Wang ◽  
Hui Wang
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Secondary Wall ◽  
Phenol Formaldehyde ◽  
Middle Lamella ◽  
Adhesive Bond ◽  
Cellular Level ◽  
Bond Line ◽  
Line Region ◽  
Penetration Behavior

To find out the penetration of PF into the wood cell wall and its effects onthe mechanical properties in the cellular level, the elastic modulus and hardness of secondary wall (S2layer) and compound corner middle lamella (CCML) near PF bond line region were determined by nanoindentation. Compare to the reference cell walls (unaffected by PF), PF penetration into the wood tissues showed improved elastic modulus and hardness. And the mechanical properties decreased slowly with the increasing the distance from the bond line, which are attributed to the effects of PF penetration into S2layer and CCML. The reduced elastic modulus variations were from18.8 to 14.4 GPa for S2layer, and from10.1 to 7.65 GPa for CCML. The hardness was from 0.67 to 0.52 GPa for S2layer, and from 0.65 to 0.52 GPa for CCML. In each test viewpoint place, the average hardness of CCML was almost as high as that of S2layer, but the reduced elastic modulus was about 50% less than that of S2layer. But the increase ratio of mechanical properties was close. All the results showed PF penetrates into the CCML. The penetration behavior and penetration depth from bond line were similar in both S2layer and CCML.

Distribution of juvenile wood in two stems of Larixlaricina

1986 ◽  
Vol 16 (5) ◽  
pp. 1041-1049 ◽  
Author(s):  
K. C. Yang ◽  
C. A. Benson ◽  
J. K. Wong
Keyword(s):  
Juvenile Wood ◽  
Growth Ring ◽  
Ring Width ◽  
Tree Level ◽  
Growth Rings ◽  
Vertical Variation ◽  
Strong Negative Correlation ◽  
Ring Number ◽  
Tracheid Length ◽  
Growth Ring Width

The distribution and vertical variation of juvenile wood was studied in an 81-year-old dominant tree and an 83-year-old suppressed tree of Larixlaricina (Du Roi) K. Koch. Two criteria, growth ring width and tracheid length, were used to demarcate the boundary of juvenile wood. The width of juvenile wood, expressed in centimetres and the number of growth rings, decreased noticeably from the base to the top of the tree. The volume of juvenile wood decreased in a similar pattern. These decreasing trends had a strong negative correlation with the year of formation of cambial initials at a given tree level. The length of these cambial initials decreased with increasing age of formation of the cambial initials. In the juvenile wood zone, there was a positive linear regression between the growth ring number (age) and the tracheid length. The slopes of these regression lines at various tree levels increased as the age of the year of formation of the cambial initials increased. At a given tree level, the length of tracheids increased from the pith to a more uniform length near the bark. However, the number of years needed to attain a more uniform tracheid length decreased from the base to the top of the tree. These relationships suggest that the formation of juvenile wood is related to the year of formation of the cambial initials. Consequently, the juvenile wood is conical in shape, tapering towards the tree top.

Lignin distribution in waterlogged archaeological Picea abies (L.) Karst degraded by erosion bacteria

Holzforschung ◽  
2014 ◽  
Vol 68 (7) ◽  
pp. 791-798 ◽  
Author(s):  
Nanna Bjerregaard Pedersen ◽  
Uwe Schmitt ◽  
Gerald Koch ◽  
Claus Felby ◽  
Lisbeth Garbrecht Thygesen
Keyword(s):  
Picea Abies ◽  
Lignin Content ◽  
Middle Lamella ◽  
Uv Absorbance ◽  
Tem Analysis ◽  
Lignin Distribution ◽  
Transmission Electron ◽  
Residual Material ◽  
Ray Parenchyma Cells ◽  
Very High

Abstract The lignin distribution in poles of waterlogged archaeological Picea abies (L.) Karst, which was decayed by erosion bacteria (EB) under anoxic conditions for approximately 400 years, was topochemically identified by transmission electron microscopy (TEM) and high resolution UV-microspectrophotometry (UMSP). Lignin rich cell wall compartments such as cell corner (CC), compound middle lamella (CML), torus, initial pit border and mild compression wood (CW) appeared morphologically well preserved together with S1 and S3 layers and epithelial and ray parenchyma cells. Residual material (RM) from degraded S2 showed a varied lignin distribution as evidenced by the different local UV-absorbance intensities. However, evaluation of UV-absorbance line spectra of RM revealed no change in conjugation of the aromatic ring system. Presence of RM with both very low and very high lignin absorbances showed evidence for disassembly of lignin during degradation combined with aggregation of lignin fragments and physical movement of these fractions. In contrast to TEM analysis, locally decreasing lignin content was found by UMSP in CML regions.

An ultrastructural study of acid phosphatase localization in Phaseolus vulgaris xylem by the use of an azo-dye method

1975 ◽  
Vol 19 (3) ◽  
pp. 543-561
Author(s):  
I. Charvat ◽  
K. Esau
Keyword(s):  
Acid Phosphatase ◽  
Phaseolus Vulgaris ◽  
Azo Dye ◽  
Secondary Wall ◽  
Parenchyma Cell ◽  
Middle Lamella ◽  
Primary Cell Wall ◽  
Vessel Element ◽  
Primary Wall ◽  
Final Reaction

The localization of acid phosphatase during xylem development has been examined in the bean, Phaseolus vulgaris. The azo dye, the final reaction product, is initially prominent in the dictyosomes, vesicles apparently participating in secondary wall formation, and in the middle lamella of the young vessel element. Final reaction particles are also present in mitochondria, chloroplasts, and certain vacuoles and are sparsely scattered in the cytoplasm. At a later stage of vessel differentiation, the azo dye is concentrated in the disintegrating cytoplasm and along the fibrils of the partially hydrolysed primary wall and middle lamella. In the mature vessel element, the azo dye is still present along the disintegrated primary wall at the side of the vessel and covers the secondary wall. In the parenchyma cell adjacent to the vessel element, acid phosphatase localization is found in the dictyosomes, endoplasmic reticulum, mitochondria, small vacuoles, and the middle lamella. The controls from all stages of vessel element development were free of azo dye particles. The concentration of acid phosphatase along the secondary walls of the mature vessels and in the middle lamella between other cells indicates that this enzyme has other functions besides autolysis of the cytoplasm and primary cell wall. Acid phosphatase may participate in the formation of the secondary wall and may also have a role in the secretion and transport of sugars.

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