Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids
<b> </b>A sequential chemical extraction with a defined series of eluotropic organic solvents with an increasing polarity (trichloromethane < ethyl acetate < acetone < acetonitrile < <i>n</i>-propanol < methanol) was performed on peat-bog humic acid. Six organi...
Main Authors: | , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2021-03-01
|
Series: | Agronomy |
Subjects: | |
Online Access: | https://www.mdpi.com/2073-4395/11/3/587 |
id |
doaj-8c3e6fb00a4944dab537596e95811195 |
---|---|
record_format |
Article |
spelling |
doaj-8c3e6fb00a4944dab537596e958111952021-03-20T00:07:12ZengMDPI AGAgronomy2073-43952021-03-011158758710.3390/agronomy11030587Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic AcidsVojtěch Enev0Petr Sedláček1Leona Kubíková2Šárka Sovová3Leoš Doskočil4Martina Klučáková5Miloslav Pekař6Institute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicInstitute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicInstitute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicInstitute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicMaterials Research Centre, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicInstitute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech RepublicInstitute of Physical and Applied Chemistry, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic<b> </b>A sequential chemical extraction with a defined series of eluotropic organic solvents with an increasing polarity (trichloromethane < ethyl acetate < acetone < acetonitrile < <i>n</i>-propanol < methanol) was performed on peat-bog humic acid. Six organic fractions were obtained and subjected to a physicochemical characterization utilizing methods of structural and compositional analysis. Advanced spectroscopic techniques such as Attenuated Total Reflectance (ATR-FTIR), total luminescence, and liquid-state <sup>13</sup>C NMR spectrometry were combined with elemental analysis of the organic fractions. In total, the procedure extracted about 57% (wt.) of the initial material; the individual fractions amounted from 1.1% to 19.7%. As expected, the apolar solvents preferentially released lipid-like components, while polar solvents provided organic fractions rich in oxygen-containing polar groups with structural parameters closer to the original humic material. The fraction extracted with acetonitrile shows distinct structural features with its lower aromaticity and high content of protein-like structural motifs. The last two—alcohol extracted—fractions show the higher content of carbohydrate residues and their specific (V-type) fluorescence suggests the presence of plant pigment residues. The extraction procedure is suggested for further studies as a simple but effective way to decrease the structural complexity of a humic material enabling its detail and more conclusive compositional characterization.https://www.mdpi.com/2073-4395/11/3/587transitional peat-bogEutric Histosolhumic acidorganic fractionsequential chemical extractionabsorption parameters |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Vojtěch Enev Petr Sedláček Leona Kubíková Šárka Sovová Leoš Doskočil Martina Klučáková Miloslav Pekař |
spellingShingle |
Vojtěch Enev Petr Sedláček Leona Kubíková Šárka Sovová Leoš Doskočil Martina Klučáková Miloslav Pekař Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids Agronomy transitional peat-bog Eutric Histosol humic acid organic fraction sequential chemical extraction absorption parameters |
author_facet |
Vojtěch Enev Petr Sedláček Leona Kubíková Šárka Sovová Leoš Doskočil Martina Klučáková Miloslav Pekař |
author_sort |
Vojtěch Enev |
title |
Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids |
title_short |
Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids |
title_full |
Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids |
title_fullStr |
Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids |
title_full_unstemmed |
Polarity-Based Sequential Extraction as a Simple Tool to Reveal the Structural Complexity of Humic Acids |
title_sort |
polarity-based sequential extraction as a simple tool to reveal the structural complexity of humic acids |
publisher |
MDPI AG |
series |
Agronomy |
issn |
2073-4395 |
publishDate |
2021-03-01 |
description |
<b> </b>A sequential chemical extraction with a defined series of eluotropic organic solvents with an increasing polarity (trichloromethane < ethyl acetate < acetone < acetonitrile < <i>n</i>-propanol < methanol) was performed on peat-bog humic acid. Six organic fractions were obtained and subjected to a physicochemical characterization utilizing methods of structural and compositional analysis. Advanced spectroscopic techniques such as Attenuated Total Reflectance (ATR-FTIR), total luminescence, and liquid-state <sup>13</sup>C NMR spectrometry were combined with elemental analysis of the organic fractions. In total, the procedure extracted about 57% (wt.) of the initial material; the individual fractions amounted from 1.1% to 19.7%. As expected, the apolar solvents preferentially released lipid-like components, while polar solvents provided organic fractions rich in oxygen-containing polar groups with structural parameters closer to the original humic material. The fraction extracted with acetonitrile shows distinct structural features with its lower aromaticity and high content of protein-like structural motifs. The last two—alcohol extracted—fractions show the higher content of carbohydrate residues and their specific (V-type) fluorescence suggests the presence of plant pigment residues. The extraction procedure is suggested for further studies as a simple but effective way to decrease the structural complexity of a humic material enabling its detail and more conclusive compositional characterization. |
topic |
transitional peat-bog Eutric Histosol humic acid organic fraction sequential chemical extraction absorption parameters |
url |
https://www.mdpi.com/2073-4395/11/3/587 |
work_keys_str_mv |
AT vojtechenev polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT petrsedlacek polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT leonakubikova polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT sarkasovova polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT leosdoskocil polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT martinaklucakova polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids AT miloslavpekar polaritybasedsequentialextractionasasimpletooltorevealthestructuralcomplexityofhumicacids |
_version_ |
1724212362685186048 |