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Updated: Jun 5, 2025
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Preparation of Fungal and Plant Materials for Structural Elucidation Using Dynamic Nuclear Polarization Solid-State NMR
Published on: February 12, 2019
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Chemical structure characterization of polysaccharides using diffusion ordered NMR spectroscopy (DOSY).
Mariana Mazetto de Carvalho1, Christiane Færestrand Ellefsen1, Andrea Angelov Eltvik1
1Department of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, NO-136 Oslo, Norway.
Carbohydrate Polymers
|December 5, 2024
Summary
Diffusion Ordered Spectroscopy (DOSY) NMR successfully differentiated β-glucans from yeast and mushrooms. This technique distinguishes polysaccharide linkage patterns, aiding structure-activity relationship studies.
Area of Science:
- Carbohydrate Chemistry
- Analytical Chemistry
- Spectroscopy
Background:
- Polysaccharides, such as β-glucans, exhibit diverse biological activities influenced by their chemical structures.
- Distinguishing between chemically similar polysaccharides with varying linkage patterns is crucial for understanding their functions.
- Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful tool for polysaccharide characterization.
Purpose of the Study:
- To evaluate the potential of DOSY NMR spectroscopy in differentiating chemically related polysaccharides based on their linkage patterns.
- To compare the structural characteristics of β-glucans from yeast (Saccharomyces cerevisiae) and mushroom (Pleurotus eryngii) using DOSY NMR.
- To assess the utility of DOSY NMR for structure-activity relationship studies of polysaccharides.
Main Methods:
- Isolation and characterization of β-glucans from yeast, mushroom, and Laminaria digitata.
- Methylation analysis and 1D/2D NMR spectroscopy for initial structural elucidation.
- Diffusion Ordered Spectroscopy (DOSY) NMR to analyze molecular diffusion and differentiate polysaccharide components.
Main Results:
- All analyzed β-glucans contained →3)-Glcp-(1→, →3,6)-Glcp-(1→, Glcp-(1→, and →6)-Glcp-(1→ linkages.
- DOSY NMR revealed that yeast β-glucans exhibited the same diffusion time for →3)-Glcp-(1→ and →6)-Glcp-(1→ units, indicating a single polysaccharide.
- Mushroom β-glucans showed different diffusion times for these units, suggesting the presence of distinct polysaccharides.
Conclusions:
- DOSY NMR spectroscopy can effectively distinguish between different linkage patterns in chemically related polysaccharides.
- The technique provides valuable insights into the structural heterogeneity of polysaccharide mixtures.
- DOSY NMR is a promising tool for polysaccharide identification and contributes to structure-activity correlation studies.
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