Determination of the Primary and Fine Structures of a Galactomannan from the Seed of Gleditsia triacanthos f. inermis L

• Published in: Applied biochemistry and microbiology Vol. 39; no. 4; pp. 398 - 402
• Main Authors: Egorov, A V, Mestechkina, N M, Shcherbukhin, V D
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.07.2003
• Subjects: Aqueous solutions; Gleditsia triacanthos
• ISSN: 0003-6838; 1608-3024
• DOI: 10.1023/A:1024524719296

Galactomannan, a polysaccharide with a molecular weight of 660 kDa, was isolated for the first time from the seed of Gleditsia triacanthos f. inermis (yield, 15.4%). Its aqueous solutions were optically active ([α]^sub D^ = +31.0°) and highly viscous ([η] = 578 ml/g). Analysis of this heteropolysaccharide using chemical, enzymatic, and chromatographic procedures, as well as IR and ^sup 13^C NMR spectroscopy, showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.42 : 1). The main chain of this galactomannan comprises 1,4-β-D-mannopyranose residues, 41% of which are substituted at C6 with single residues of α-D-galactopyranose. The probability of occurrence in the chain of mannobiose units substituted otherwise, determined experimentally, was 0.16 for the Man-Man unit, 0.50 for the Gal(Man-Man) and (Man-Man)Gal units, and 0.34 for the disubstituted Gal(Man-Man)Gal unit.[PUBLICATION ABSTRACT]