Direct Measurement of Plant Cellulose Microfibril and Bundles in Native Cell Walls

Abstract Changes in structure and lignin chemistry were investigated in ash wood thermally modified (TMW) by the thermo-vacuum (Termovuoto) process for 3 h at 190–220°C by means of light, fluorescence, and transmission electron (TEM) microscopy combined with histo/cytochemistry. Variation in changes in native cell color in TMWs was positively correlated with differences in lignin content between cell types and cell wall regions in the reference wood. Histochemical staining showed increasing amounts of acidic groups in TMWs with different response to ethanol extraction between secondary cell walls and CMLcc (compound middle lamella/middle lamella cell corner) regions. Fluorescence microscopy of TMWs and references showed a difference in intensity and color emission of lignin autofluorescence, reflecting modification of lignin in TMWs. Changes in histochemistry and fluorescence were prominent at and above 200°C. With TEM, increased intensity of lignin staining and distortion of fiber S1 layers were detected in TMW treated for 3 h at 220°C (TMW3 h, 220°C). TMW3 h, 220°C differed significantly in molecular ultrastructure of fiber cell walls compared to references, such as loss of the lamellar structure and size and distribution of lignin aggregates. The modification in CMLcc structure in ash TMW3 h, 220°C is different from that of softwoods.

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The mechanosorptive effect in Pinus radiata D. Don.

Holzforschung ◽

10.1515/hf.2005.091 ◽

2005 ◽

Vol 59 (5) ◽

pp. 552-558 ◽

Cited By ~ 8

Author(s):

Kenneth M. Entwistle

Keyword(s):

Applied Stress ◽

Pinus Radiata ◽

Cell Walls ◽

Cellulose Microfibril ◽

Stress Component ◽

Single Specimen ◽

Shear Stress Component ◽

Effect Analysis ◽

Detailed Model ◽

Valid Data

Abstract Measurements are reported of the mechanosorptive strain in Pinus radiata specimens stressed either in torsion or in bending. It is demonstrated that, to secure valid data, correction must be made for the moisture-induced distortion at zero load. A series of measurements can be made on a single specimen if two successive mechano-sorptive loading cycles are used and the sense of the stress is reversed for the second cycle. At the end of this procedure the specimen has reverted to its original dimensions. The mechanosorptive strain is shown to vary linearly with the applied stress; the ratio of the mechanosorptive strain to the initial elastic strain is therefore an appropriate way of quantifying the mechanosorptive effect. Analysis of torsion and bending data reveals that there is a strong correlation between the magnitude of the mechanosorptive strain and the shear stress component of the applied stress along the cellulose microfibril direction. It is suggested that the mechanosorptive effect arises from the effect of stress on the distribution of hydrogen bonds in hemicelluloses. A detailed model must await more information about the molecular structure of hemicelluloses in the cell walls.

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The Arrangement and Size of Cellulose Microfibril Aggregates in the Cell Walls of Sclerenchyma Fibers and Parenchyma Tissue in Bamboo

JOURNAL OF RENEWABLE MATERIALS ◽

10.32604/jrm.2021.015973 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2291-2301

Author(s):

Wenting Ren ◽

Fei Guo ◽

Minghui Liu ◽

Haocheng Xu ◽

Hankun Wang ◽

...

Keyword(s):

Cell Walls ◽

Cellulose Microfibril ◽

Sclerenchyma Fibers ◽

Parenchyma Tissue

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Generation mechanism of growth stresses in wood cell walls: roles of lignin deposition and cellulose microfibril during cell wall maturation

Wood Science and Technology ◽

10.1007/bf00704840 ◽

1998 ◽

Vol 32 (3) ◽

pp. 171-182 ◽

Cited By ~ 58

Author(s):

H. Yamamoto

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Cellulose Microfibril ◽

Generation Mechanism ◽

Growth Stresses ◽

Mechanism Of Growth ◽

Lignin Deposition

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Callose: a multifunctional (1, 3)-β–d-glucan involved in morphogenesis and function of angiosperm stomata

Journal of Biological Research-Thessaloniki ◽

10.1186/s40709-021-00150-9 ◽

2021 ◽

Vol 28 (1) ◽

Author(s):

Panagiotis Apostolakos ◽

Eleni Giannoutsou ◽

Basil Galatis

Keyword(s):

Cell Walls ◽

Pore Formation ◽

Cellulose Microfibril ◽

Vigna Sinensis ◽

Matrix Cell ◽

Wall Materials ◽

Asplenium Nidus ◽

And Function ◽

Cell Wall Materials

Abstract Background Although the cellulose microfibril organization in guard cell (GC) walls play a crucial role in the mechanism of the stomatal function, recent work showed that matrix cell wall materials are also involved. Especially in the kidney-shaped stomata of the fern Asplenium nidus, callose actively participates in the mechanism of opening and closure of the stomatal pore. Scope The present review briefly presents and discusses recent findings concerning the distribution and role of callose in the kidney-shaped stomata of the dicotyledon Vigna sinensis as well as in the dumbbell-shaped stomata of the monocotyledon Zea mays. Conclusion The discussed data support that, in both categories of angiosperm stomata, callose is implicated in the mechanism of stomatal pore formation and stomata function by locally affecting the mechanical properties of the GC cell walls.

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