Structural characterisation of a new O-methylated heteroglycan, colleman, from the cyanolichen Collema flaccidum

• Published in: Carbohydrate polymers Vol. 80; no. 3; pp. 799 - 807
• Main Authors: Jensen, J.S.R.E., Petersen, B.O., Veselinovic, T., Olafsdottir, E.S., Duus, J.Ø., Omarsdottir, S.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 05-05-2010; Elsevier
• Subjects: Applied sciences; Biological and medical sciences; Collema flaccidum; Colleman; Cyanolichen; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Heteroglycan; Microbiology; Morphology, structure, chemical composition; Mycology; Natural polymers; NMR; Physicochemistry of polymers; Starch and polysaccharides; Heteroglycan; Cyanolichen; NMR; Colleman; Collema flaccidum; Ascomycota; Soxhlet extraction; Molecular structure; Chemical isolation; Experimental study; Glycan; Fungi; Plant origin; Oside polymer
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2009.12.035

An alkali-extractable heteroglycan, colleman, was isolated from the cyanolichen
Collema flaccidum, using ethanol fractionation and anion-exchange chromatography. The average molecular weight was estimated to be 360
kDa. Structural characterisation of the heteroglycan was performed by high-field NMR spectroscopy (1D proton, 2D-COSY, NOESY, 2D-TOCSY,
1H
13C-HSQC, HMBC, H2BC and HSQC-NOESY).
According to the data obtained, the structure of colleman is composed of repeating units of
A,
B,
C and
D in approximate molar ratio 5:5:2:1;
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