[Composition and structure of a galactomannan macromolecules from seeds of Astragalus lehmannianus Bunge]. / Sostav i struktura makromolekuly galaktomannana semian Astragalus lehmannianus Bunge.
Prikl Biokhim Mikrobiol
; 36(5): 582-7, 2000.
Article
em Ru
| MEDLINE
| ID: mdl-11042884
ABSTRACT
The composition and structure of a galactomannan from seeds of Astragalus lehmannianus, an endemic legume species, is reported for the first time. The purified galactomannan (yield, 4.8%) contained 55% D-mannose and 45% D-galactose and had a molecular weight of 997.03 kDa. Its aqueous solutions were optically active and highly viscous (the specific rotation, [alpha]D, equaled +81.3 degrees; the characteristic viscosity, [eta], 868.4 ml/g). Chemical, chromatographic, and spectral (IR and 13C-NMR spectroscopy) methods were used to demonstrate that the main chain of the molecule is formed by residues of 1,4-beta-D-mannopyranose, 78% of which are substituted at position 6 with single alpha-D-galactopyranose. The distribution of galactose along the chain was calculated from NMR spectra frequencies of occurrence, per pair of neighboring mannose units, of (1) two substituents, (2) one substituent, and (3) no substituents were 65.3, 31.5, and 3.2%, respectively. The specific rotation of galactomannans was shown to correlate with their content of galactose.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plantas Medicinais
/
Fabaceae
/
Mananas
Idioma:
Ru
Revista:
Prikl Biokhim Mikrobiol
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Federação Russa