Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic
Free radicals (FRs) are intermediate participants in the transformation process of soil organic matter, and free radical activity is a fundamental property of humic substances. The aim of this work was to conduct a comparative study of the paramagnetic properties of humic acids (HAs) isolated from H...
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MDPI AG
2023
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Online Access: | https://doi.org/10.3390/molecules29010104 https://doaj.org/article/778639651d2a4fa8bbea37bec786e944 |
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ftdoajarticles:oai:doaj.org/article:778639651d2a4fa8bbea37bec786e944 2024-02-11T10:00:58+01:00 Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic Evgeny Lodygin Roman Vasilevich Evgeny Abakumov 2023-12-01T00:00:00Z https://doi.org/10.3390/molecules29010104 https://doaj.org/article/778639651d2a4fa8bbea37bec786e944 EN eng MDPI AG https://www.mdpi.com/1420-3049/29/1/104 https://doaj.org/toc/1420-3049 doi:10.3390/molecules29010104 1420-3049 https://doaj.org/article/778639651d2a4fa8bbea37bec786e944 Molecules, Vol 29, Iss 1, p 104 (2023) soil organic matter free radicals EPR spectroscopy Histosols Organic chemistry QD241-441 article 2023 ftdoajarticles https://doi.org/10.3390/molecules29010104 2024-01-14T01:38:56Z Free radicals (FRs) are intermediate participants in the transformation process of soil organic matter, and free radical activity is a fundamental property of humic substances. The aim of this work was to conduct a comparative study of the paramagnetic properties of humic acids (HAs) isolated from Histosols by electron paramagnetic resonance (EPR) spectroscopy. The studied Histosols are found in permafrost peatlands in four natural geographic subzones of the European Arctic (from forest tundra to northern tundra). The results obtained showed that in anaerobic conditions on the peatlands in the tundra zone, the formation of semiquinone-type radicals occurs through the reduction of quinone fragments of HAs and leads to an increase in the concentration of paramagnetic centres within HAs. PCA analysis allowed us to reveal relationships between the properties of the initial raw peat samples, the molecular composition of the isolated HAs, and their paramagnetic parameters. It was found that FR localization occurs predominantly on aromatic fragments of lignin nature, which are confined to the low molecular weight fraction of HAs. The g-factor values of the EPR spectra of HAs indicate the presence of carbon- and oxygen-centred FRs in the HA structure, with a predominance of the latter. Article in Journal/Newspaper Arctic permafrost Tundra Directory of Open Access Journals: DOAJ Articles Arctic Molecules 29 1 104 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
soil organic matter free radicals EPR spectroscopy Histosols Organic chemistry QD241-441 |
spellingShingle |
soil organic matter free radicals EPR spectroscopy Histosols Organic chemistry QD241-441 Evgeny Lodygin Roman Vasilevich Evgeny Abakumov Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
topic_facet |
soil organic matter free radicals EPR spectroscopy Histosols Organic chemistry QD241-441 |
description |
Free radicals (FRs) are intermediate participants in the transformation process of soil organic matter, and free radical activity is a fundamental property of humic substances. The aim of this work was to conduct a comparative study of the paramagnetic properties of humic acids (HAs) isolated from Histosols by electron paramagnetic resonance (EPR) spectroscopy. The studied Histosols are found in permafrost peatlands in four natural geographic subzones of the European Arctic (from forest tundra to northern tundra). The results obtained showed that in anaerobic conditions on the peatlands in the tundra zone, the formation of semiquinone-type radicals occurs through the reduction of quinone fragments of HAs and leads to an increase in the concentration of paramagnetic centres within HAs. PCA analysis allowed us to reveal relationships between the properties of the initial raw peat samples, the molecular composition of the isolated HAs, and their paramagnetic parameters. It was found that FR localization occurs predominantly on aromatic fragments of lignin nature, which are confined to the low molecular weight fraction of HAs. The g-factor values of the EPR spectra of HAs indicate the presence of carbon- and oxygen-centred FRs in the HA structure, with a predominance of the latter. |
format |
Article in Journal/Newspaper |
author |
Evgeny Lodygin Roman Vasilevich Evgeny Abakumov |
author_facet |
Evgeny Lodygin Roman Vasilevich Evgeny Abakumov |
author_sort |
Evgeny Lodygin |
title |
Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
title_short |
Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
title_full |
Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
title_fullStr |
Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
title_full_unstemmed |
Relating Paramagnetic Properties to Molecular Parameters of Humic Acids Isolated from Permafrost Peatlands in the European Arctic |
title_sort |
relating paramagnetic properties to molecular parameters of humic acids isolated from permafrost peatlands in the european arctic |
publisher |
MDPI AG |
publishDate |
2023 |
url |
https://doi.org/10.3390/molecules29010104 https://doaj.org/article/778639651d2a4fa8bbea37bec786e944 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic permafrost Tundra |
genre_facet |
Arctic permafrost Tundra |
op_source |
Molecules, Vol 29, Iss 1, p 104 (2023) |
op_relation |
https://www.mdpi.com/1420-3049/29/1/104 https://doaj.org/toc/1420-3049 doi:10.3390/molecules29010104 1420-3049 https://doaj.org/article/778639651d2a4fa8bbea37bec786e944 |
op_doi |
https://doi.org/10.3390/molecules29010104 |
container_title |
Molecules |
container_volume |
29 |
container_issue |
1 |
container_start_page |
104 |
_version_ |
1790596694435430400 |