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Determination of the Glycogen Content in Cyanobacteria
Published on: July 17, 2017
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Complex arabinose-containing polysaccharides from cyanobacterium Nostoc sp.: Extraction, structural characterization
Amal D Premarathna1, Vitalijs Rjabovs2, Sanjida Humayun1
1School of Natural Sciences and Health, Tallinn University, Narva mnt 29, 10120 Tallinn, Estonia.
International Journal of Biological Macromolecules
|March 9, 2025
Summary
Freshwater Nostoc sp. polysaccharides (NSPs) were characterized, revealing unique structures and significant antioxidant activity, particularly from cold extraction. These findings highlight NSPs
Area of Science:
- Biochemistry and Polymer Science: Focus on the structural elucidation and characterization of novel polysaccharides from freshwater cyanobacteria.
Background:
- Freshwater Nostoc sp. polysaccharides (NSPs) remain underexplored regarding their structural and biological properties.
- Comprehensive characterization is needed to understand their potential applications.
Purpose of the Study:
- To characterize freshwater Nostoc sp. polysaccharides (NSPs) using advanced analytical techniques.
- To evaluate the extraction efficiency and antioxidant activities of NSPs under different temperature regimes.
- To investigate the monosaccharide composition, glycosylation patterns, and molecular weight distribution of NSPs.
Main Methods:
- Polysaccharide extraction using cold (25°C) and hot (95°C) regimes.
- Structural analysis via 1H and 13C NMR, FTIR spectroscopy, HP-SEC, and HPAEC-PAD.
- Quantification of total phenolic content, total sugar, and protein content.
Main Results:
- Hot extraction yielded higher NSPs (34.9%) compared to cold extraction (27.6%).
- NSPs are non-sulfated, primarily composed of mannose, arabinose, glucuronic acid, and glucose residues, with β-d-glucuronic acid being predominant.
- Polysaccharides from inner fluid fractions showed higher molecular weight (up to 480 kDa); cold-extracted NSPs exhibited the highest antioxidant activity.
Conclusions:
- Nostoc sp. polysaccharides possess unique structural features and significant antioxidant properties.
- Extraction temperature influences yield and potentially polysaccharide characteristics.
- NSPs demonstrate considerable potential for applications in skincare, food, pharmaceutical, and biotechnology industries.
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