An Analytical Toolbox for Fast and Straightforward Structural Characterisation of Commercially Available Tannins

Both condensed and hydrolysable tannins represent versatile natural polyphenolic structures exhibiting a broad range of activities that could be exploited in various fields including nutraceutics, cosmesis, consumer care, household and pharmaceutical applications. Various tannins are commercially available nowadays for use in such application fields. We have analysed a representative selection of commercially available condensed and hydrolysable tannins for structural features and purity. Using a combination of quantitative 31P NMR spectroscopy, HSQC measurements, MALDI-ToF analyses, gel permeation chromatography and wet chemical analysis, detailed structural characterisations and descriptions were possible, allowing for verification and falsification of claimed structural features.

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Structural elucidation of lignins from corncob acid hydrolysis residue by enzymatic mild acidolysis and deep eutectic solvent pretreatment

BioResources ◽

10.15376/biores.15.2.4362-4372 ◽

2020 ◽

Vol 15 (2) ◽

pp. 4362-4372

Author(s):

Na Li ◽

Chao Cao ◽

Lupeng Shao ◽

Chao Wang ◽

Yu Liu ◽

...

Keyword(s):

Acid Hydrolysis ◽

31P Nmr ◽

Structural Characteristics ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Gel Permeation Chromatography ◽

Structural Features ◽

Molar Ratio ◽

Efficient Extraction ◽

Hydrolysis Residue

Achieving mild and efficient extraction of high purity lignin from corncob acid hydrolysis residue is essential for efficient lignin application. In this study, enzymatic/mild acidolysis lignin (EMAL) and deep eutectic solvent (DES)-lignin were extracted from corncob acid hydrolysis residue. The structural features of the two lignin fractions were investigated by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), and 31P-nuclear magnetic resonance (31P-NMR). The highest DES-lignin yield of 58.8 wt% was achieved at 120 °C with a choline chloride-to-lactic acid (ChCl-to-Lac) molar ratio of 1:10 and a reaction time of 12 h. The FTIR analysis indicated a higher amount of guaiacyl units in EMAL than DES-lignin. Furthermore, condensation and fragmentation occurred simultaneously under DES pretreatment, but the fragmentation reaction was dominant. The structural characteristics investigated will allow for more effective lignin usage.

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Characterization of Eucalyptus nitens Lignins Obtained by Biorefinery Methods Based on Ionic Liquids

Molecules ◽

10.3390/molecules25020425 ◽

2020 ◽

Vol 25 (2) ◽

pp. 425 ◽

Cited By ~ 4

Author(s):

Lucía Penín ◽

Heiko Lange ◽

Valentín Santos ◽

Claudia Crestini ◽

Juan Carlos Parajó

Keyword(s):

Ionic Liquid ◽

31P Nmr ◽

Solid Phase ◽

Gel Permeation Chromatography ◽

Structural Features ◽

Eucalyptus Nitens ◽

Hydrogen Sulfate ◽

Hydrothermal Processing ◽

Lignin Recovery

Eucalyptus nitens wood samples were subjected to consecutive stages of hydrothermal processing for hemicellulose solubilization and delignification with an ionic liquid, i.e., either 1-butyl-3-methylimidazolium hydrogen sulfate or triethylammonium hydrogen sulfate. Delignification experiments were carried out a 170 °C for 10–50 min. The solid phases from treatments, i.e., cellulose-enriched solids, were recovered by centrifugation, and lignin was separated from the ionic liquid by water precipitation. The best delignification conditions were identified on the basis of the results determined for delignification percentage, lignin recovery yield, and cellulose recovery in solid phase. The lignins obtained under selected conditions were characterized in deep by 31P-NMR, 13C-NMR, HSQC, and gel permeation chromatography. The major structural features of the lignins were discussed in comparison with the results determined for a model Ionosolv lignin.

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Quantitative Determination of Krill Oil Composition by ATR-FTIR, NIR, and 31P NMR Spectroscopy

10.21748/am20.144 ◽

2020 ◽

Author(s):

Ashraf Ismail ◽

Sanaz Molaye Moghaddam ◽

Jean-Pierre MetabanzoulouSarya Aziz ◽

Jacqueline Sedman ◽

Mazen Bahadi

Keyword(s):

Nmr Spectroscopy ◽

Quantitative Determination ◽

31P Nmr ◽

31P Nmr Spectroscopy ◽

Krill Oil ◽

Oil Composition

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Enzymatic decomposition of a locked nucleoside phosphoramidate monitored by 31P NMR spectroscopy

Collection Symposium Series ◽

10.1135/css201414356 ◽

2014 ◽

Author(s):

Eliška Procházková ◽

Hubert Hřebabecký ◽

Radim Nencka ◽

Martin Dračínský

Keyword(s):

Nmr Spectroscopy ◽

31P Nmr ◽

31P Nmr Spectroscopy

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Effect of Dietary Magnesium on Post Mortem Phosphocreatine Utilization in Skeletal Muscle of Swine: A Non-Invasive Study Using 31P-NMR Spectroscopy

Acta Veterinaria Scandinavica ◽

10.1186/bf03548184 ◽

1993 ◽

Vol 34 (4) ◽

pp. 397-404

Author(s):

B. Moesgaard ◽

I. Errebo Larsen ◽

B. Quistorff ◽

I. Therkelsen ◽

V. Grøsfjeld Christensen ◽

...

Keyword(s):

Skeletal Muscle ◽

Nmr Spectroscopy ◽

31P Nmr ◽

31P Nmr Spectroscopy ◽

Post Mortem ◽

Non Invasive ◽

Dietary Magnesium

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Unravelling the dissolution mechanism of polyphosphate glasses by 31P NMR spectroscopy: ligand competition and reactivity of intermediate complexes

Dalton Transactions ◽

10.1039/d0dt03381b ◽

2021 ◽

Author(s):

Dahiana Andrea Avila Salazar ◽

Peter Bellstedt ◽

Atsuhiro Miura ◽

Yuki Oi ◽

Toshihiro Kasuga ◽

...

Keyword(s):

Nuclear Magnetic Resonance ◽

Solid State ◽

Nmr Spectroscopy ◽

Biomedical Applications ◽

Structural Changes ◽

31P Nmr ◽

Dissolution Mechanism ◽

31P Nmr Spectroscopy ◽

Glass Dissolution ◽

Polyphosphate Glasses

Phosphate glass dissolution can be tailored via compositional and subsequent structural changes, which is of interest for biomedical applications such as therapeutic ion delivery. Here, solid-state 31P nuclear magnetic resonance...

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