Next Article in Journal
New Polyhedral Oligomeric Silsesquioxanes-Based Fluorescent Ionic Liquids: Synthesis, Self-Assembly and Application in Sensors for Detecting Nitroaromatic Explosives
Next Article in Special Issue
Lignin Structure and Solvent Effects on the Selective Removal of Condensed Units and Enrichment of S-Type Lignin
Previous Article in Journal
Responsive Protein Hydrogels Assembled from Spider Silk Carboxyl-Terminal Domain and Resilin Copolymers
Previous Article in Special Issue
Acylation of Lignin with Different Acylating Agents by Mechanical Activation-Assisted Solid Phase Synthesis: Preparation and Properties
Article Menu
Issue 8 (August) cover image

Export Article

Open AccessCommunication
Polymers 2018, 10(8), 916; https://doi.org/10.3390/polym10080916

Elucidating Tricin-Lignin Structures: Assigning Correlations in HSQC Spectra of Monocot Lignins

1
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510630, China
2
DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53706, USA
3
Department of Biological System Engineering, University of Wisconsin, Madison, WI 53706, USA
4
Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA
5
Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS), CSIC, 003495 Seville, Spain
6
Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
7
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
*
Author to whom correspondence should be addressed.
Received: 24 July 2018 / Accepted: 3 August 2018 / Published: 15 August 2018
(This article belongs to the Special Issue Lignin Polymers: Structures, Reactions and Applications)
Full-Text   |   PDF [6092 KB, uploaded 18 August 2018]   |  

Abstract

Tricin [5,7-dihydroxy-2-(4-hydroxy-3,5-dimethoxyphenyl)-4H-chromen-4-one] is a flavone that has been found to be incorporated in grass lignin polymers via 4′–O–β coupling. Herein, we investigated the tricin-lignin structure using nuclear magnetic resonance (NMR) methods by comparing the 1H–13C heteronuclear correlation (HSQC) NMR spectra of the isolated lignin with a series of dimeric and trimeric tricin-4′–O–β-ether model compounds. Results showed that the tricin moiety significantly affects the chemical shift of the Cβ/Hβ of 4′–O–β unit, producing peaks at around δC/δH 82.5–83.5/4.15–4.45, that differ from the Cβ/Hβ correlations from normal 4–O–β units formed solely by monolignols, and that have to date been unassigned. View Full-Text
Keywords: tricin; lignin; model compound; HSQC; nuclear magnetic resonance (NMR); monocot tricin; lignin; model compound; HSQC; nuclear magnetic resonance (NMR); monocot
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Lan, W.; Yue, F.; Rencoret, J.; del Río, J.C.; Boerjan, W.; Lu, F.; Ralph, J. Elucidating Tricin-Lignin Structures: Assigning Correlations in HSQC Spectra of Monocot Lignins. Polymers 2018, 10, 916.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top