In-situ visualizing selective lignin dissolution of tracheids wall in reaction wood.

Int J Biol Macromol

Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China. Electronic address:

Published: December 2022

As a renewable biological macromolecule with aromatic structure, lignin can serve as matrix substance to maintain cell wall integrity and is regarded as the natural biomass recalcitrance. Substantial differences in the cell wall lignin topochemistry between opposite (Ow) and compression wood (Cw) trachieds in Pinus bungeana Zucc. were visualized during [Emim][OAc] pretreatment at room temperature. The ionic liqiuds treatment induced a more obvious wall swelling for highly lignified Cw tracheids than that of Ow, while dynamic Raman spectra analysis indicated the higher lignin and carbohydrates removal for Ow tracheids. Raman imaging further revealed that both lignin and carbohydrates were dissolved simultaneously within the middle lamella and secondary wall of Ow and pretreatment has little effects on Cw tracheids wall. Moreover, it was demonstrated that lignin composition was the key factor to affect the composition dissolution. In particular, lignin G-units were selectively removed from cell corner middle lamella (52.3 %) and secondary wall (62.0 %) of Ow tracheids. When cotton fiber, as a reference was treated under the same conditions, lattice conversion moving from cellulose I to II occurred. The findings confirmed the important role of lignin compostion in the dissolution behavior of carbohydrate dominant tracheids wall.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijbiomac.2022.09.206DOI Listing

Publication Analysis

Top Keywords

tracheids wall
12
lignin
8
wall
8
cell wall
8
lignin carbohydrates
8
middle lamella
8
secondary wall
8
tracheids
6
in-situ visualizing
4
visualizing selective
4

Similar Publications

Brown rot fungi, the major decomposers in the boreal coniferous forests, cause a unique wood decay pattern but many aspects of brown rot decay mechanisms remain unclear. In this study, decayed wood samples were prepared by cultivation of the brown rot fungi Gloeophyllum trabeum and Coniophora puteana on Japanese coniferous wood of Cryptomeria japonica, and the cutting planes were prepared using broad ion beam (BIB) milling, which enables observation of intact wood, in addition to traditional microtome sections. Samples were observed using field-emission SEM revealing that areas inside the end walls of ray parenchyma cells were the first to be degraded.

View Article and Find Full Text PDF

The distributions of monolignol glucosides (MLGs) in compression and opposite woods of Pinus thunbergii were assessed using cryo-time-of-flight secondary ion mass spectrometry to investigate their involvement in lignification. p-Glucocoumaryl alcohol (PG) was identified in the region of the differentiating xylem adjacent to the cambial zone only in compression wood, whereas coniferin (CF) was similarly localized in both compression and opposite woods. Their distribution from the phloem to the xylem was evaluated by high-performance liquid chromatography (HPLC) using serial tangential sections.

View Article and Find Full Text PDF

Dynamic changes of heterogeneous cell wall macromolecules in differentiating conifer xylem using cytochemical localization.

Int J Biol Macromol

January 2025

Department of Wood Anatomy and Utilization, Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China; Wood Specimen Resource Center (WOODPEDIA) of National Forestry and Grassland Administration, Beijing 100091, China. Electronic address:

Article Synopsis
  • Understanding the changes in cell wall components during xylem differentiation is crucial for grasping the structure of wood, especially at the secondary cell wall layer level.
  • In the study of Pinus bungeana, it was found that crystalline cellulose and glucomannan were deposited before xylan and lignin, with lignification starting in the primary cell wall corners as the S layer developed.
  • Immunofluorescence results showed that glucomannan was deposited earlier than xylan, and while pectins were concentrated in the primary walls, they decreased as tracheid walls differentiated, with ray cells lagging behind axial tracheids in their development.
View Article and Find Full Text PDF

Strong and transparent film of naturally aligned softwood holocellulose fibers.

Carbohydr Polym

January 2025

Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, AlbaNova University Centre, SE-106 91 Stockholm, Sweden. Electronic address:

Article Synopsis
  • Mildly delignified softwood holocellulose fibers, which retain their native tracheid structure and high hemicellulose content, are essential for creating fiber-based materials from wood.
  • The challenge lies in maintaining the natural alignment of long softwood fibers during delignification, as removing too much lignin can cause structural instability and damage.
  • This study presents a method involving chemical crosslinking to enhance bonding between softwood fibers, resulting in high-performance, transparent films with impressive optical and mechanical properties.
View Article and Find Full Text PDF
Article Synopsis
  • The study examined how alcoholysis affects the cell wall structures of Cryptomeria japonica during delignification.
  • Alcoholysis at temperatures of 100-150 °C reduced lignin content and revealed structural changes, such as the formation of spherical particles that damaged cell walls.
  • The research highlights the importance of accounting for both compositional and structural changes in achieving effective delignification without harming the integrity of cell walls.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!