Impact of steam explosion on the wheat straw lignin structure studied by solution-state nuclear magnetic resonance and density functional methods

Harri Heikkinen (Corresponding Author), T. Elder, Hannu Maaheimo, Stella Rovio, Jenni Rahikainen, Kristiina Kruus, Tarja Tamminen

Research output: Contribution to journalArticleScientificpeer-review

28 Citations (Scopus)

Abstract

Chemical changes of lignin induced by the steam explosion (SE) process were elucidated. Wheat straw was studied as the raw material, and lignins were isolated by the enzymatic mild acidolysis lignin (EMAL) procedure before and after the SE treatment for analyses mainly by two-dimensional (2D) [heteronuclear single-quantum coherence (HSQC) and heteronuclear multiple-bond correlation (HMBC)] and 31P nuclear magnetic resonance (NMR). The β-O-4 structures were found to be homolytically cleaved, followed by recoupling to β-5 linkages. The homolytic cleavage/recoupling reactions were also studied by computational methods, which verified their thermodynamic feasibility. The presence of the tricin bound to wheat straw lignin was confirmed, and it was shown to participate in lignin reactions during the SE treatment. The preferred homolytic β-O-4 cleavage reaction was calculated to follow bond dissociation energies: G–O–G (guaiacyl) (69.7 kcal/mol) > G–O–S (syringyl) (68.4 kcal/mol) > G–O–T (tricin) (67.0 kcal/mol).
Original languageEnglish
Pages (from-to)10437-10444
Number of pages7
JournalJournal of Agricultural and Food Chemistry
Volume62
Issue number43
DOIs
Publication statusPublished - 2014
MoE publication typeA1 Journal article-refereed

Fingerprint

Explosions
Lignin
explosions
Steam
Straw
wheat straw
steam
Triticum
nuclear magnetic resonance spectroscopy
lignin
Magnetic Resonance Spectroscopy
Nuclear magnetic resonance
acidolysis
methodology
Computational methods
Thermodynamics
thermodynamics
raw materials
Raw materials
energy

Keywords

  • lignin
  • wheat straws
  • steam explosion
  • tricin
  • density-functional methods

Cite this

@article{c2a48a9667a3474bbbb6b8b8286b13bf,
title = "Impact of steam explosion on the wheat straw lignin structure studied by solution-state nuclear magnetic resonance and density functional methods",
abstract = "Chemical changes of lignin induced by the steam explosion (SE) process were elucidated. Wheat straw was studied as the raw material, and lignins were isolated by the enzymatic mild acidolysis lignin (EMAL) procedure before and after the SE treatment for analyses mainly by two-dimensional (2D) [heteronuclear single-quantum coherence (HSQC) and heteronuclear multiple-bond correlation (HMBC)] and 31P nuclear magnetic resonance (NMR). The β-O-4 structures were found to be homolytically cleaved, followed by recoupling to β-5 linkages. The homolytic cleavage/recoupling reactions were also studied by computational methods, which verified their thermodynamic feasibility. The presence of the tricin bound to wheat straw lignin was confirmed, and it was shown to participate in lignin reactions during the SE treatment. The preferred homolytic β-O-4 cleavage reaction was calculated to follow bond dissociation energies: G–O–G (guaiacyl) (69.7 kcal/mol) > G–O–S (syringyl) (68.4 kcal/mol) > G–O–T (tricin) (67.0 kcal/mol).",
keywords = "lignin, wheat straws, steam explosion, tricin, density-functional methods",
author = "Harri Heikkinen and T. Elder and Hannu Maaheimo and Stella Rovio and Jenni Rahikainen and Kristiina Kruus and Tarja Tamminen",
year = "2014",
doi = "10.1021/jf504622j",
language = "English",
volume = "62",
pages = "10437--10444",
journal = "Journal of Agricultural and Food Chemistry",
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publisher = "American Chemical Society ACS",
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Impact of steam explosion on the wheat straw lignin structure studied by solution-state nuclear magnetic resonance and density functional methods. / Heikkinen, Harri (Corresponding Author); Elder, T.; Maaheimo, Hannu; Rovio, Stella; Rahikainen, Jenni; Kruus, Kristiina; Tamminen, Tarja.

In: Journal of Agricultural and Food Chemistry, Vol. 62, No. 43, 2014, p. 10437-10444.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Impact of steam explosion on the wheat straw lignin structure studied by solution-state nuclear magnetic resonance and density functional methods

AU - Heikkinen, Harri

AU - Elder, T.

AU - Maaheimo, Hannu

AU - Rovio, Stella

AU - Rahikainen, Jenni

AU - Kruus, Kristiina

AU - Tamminen, Tarja

PY - 2014

Y1 - 2014

N2 - Chemical changes of lignin induced by the steam explosion (SE) process were elucidated. Wheat straw was studied as the raw material, and lignins were isolated by the enzymatic mild acidolysis lignin (EMAL) procedure before and after the SE treatment for analyses mainly by two-dimensional (2D) [heteronuclear single-quantum coherence (HSQC) and heteronuclear multiple-bond correlation (HMBC)] and 31P nuclear magnetic resonance (NMR). The β-O-4 structures were found to be homolytically cleaved, followed by recoupling to β-5 linkages. The homolytic cleavage/recoupling reactions were also studied by computational methods, which verified their thermodynamic feasibility. The presence of the tricin bound to wheat straw lignin was confirmed, and it was shown to participate in lignin reactions during the SE treatment. The preferred homolytic β-O-4 cleavage reaction was calculated to follow bond dissociation energies: G–O–G (guaiacyl) (69.7 kcal/mol) > G–O–S (syringyl) (68.4 kcal/mol) > G–O–T (tricin) (67.0 kcal/mol).

AB - Chemical changes of lignin induced by the steam explosion (SE) process were elucidated. Wheat straw was studied as the raw material, and lignins were isolated by the enzymatic mild acidolysis lignin (EMAL) procedure before and after the SE treatment for analyses mainly by two-dimensional (2D) [heteronuclear single-quantum coherence (HSQC) and heteronuclear multiple-bond correlation (HMBC)] and 31P nuclear magnetic resonance (NMR). The β-O-4 structures were found to be homolytically cleaved, followed by recoupling to β-5 linkages. The homolytic cleavage/recoupling reactions were also studied by computational methods, which verified their thermodynamic feasibility. The presence of the tricin bound to wheat straw lignin was confirmed, and it was shown to participate in lignin reactions during the SE treatment. The preferred homolytic β-O-4 cleavage reaction was calculated to follow bond dissociation energies: G–O–G (guaiacyl) (69.7 kcal/mol) > G–O–S (syringyl) (68.4 kcal/mol) > G–O–T (tricin) (67.0 kcal/mol).

KW - lignin

KW - wheat straws

KW - steam explosion

KW - tricin

KW - density-functional methods

U2 - 10.1021/jf504622j

DO - 10.1021/jf504622j

M3 - Article

VL - 62

SP - 10437

EP - 10444

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

SN - 0021-8561

IS - 43

ER -