A polysaccharide of Thea sinensis, TSA, has been isolated from the fresh leaves as a major fraction of polysaccharides. The mol. wt. was estimated to be 850,000 with [α]_D^(15)+ 25.5°(c=0.75, H_2O). The componen...A polysaccharide of Thea sinensis, TSA, has been isolated from the fresh leaves as a major fraction of polysaccharides. The mol. wt. was estimated to be 850,000 with [α]_D^(15)+ 25.5°(c=0.75, H_2O). The component sugars were determined as L-rhamnose, L-arabinose, and D-galactose in molar ratio of 0.54: 1.0: 0.94. The O-acetyl groups locating on galactose residues position 2 were also iden- tified and the content was 3.8％. The ^(13)C NMR spectrum and CrO_3 oxidation of TSA indicated the Rhamnose, Arabinose and Galactose to be in α-, α- and β-configurations, respectively. Me- thylation analysis, periodate oxidation, partial hydrolysis and ^(13) C NMR. spectrum showed that TSA. is a branched galactoarabinan.展开更多
文摘A polysaccharide of Thea sinensis, TSA, has been isolated from the fresh leaves as a major fraction of polysaccharides. The mol. wt. was estimated to be 850,000 with [α]_D^(15)+ 25.5°(c=0.75, H_2O). The component sugars were determined as L-rhamnose, L-arabinose, and D-galactose in molar ratio of 0.54: 1.0: 0.94. The O-acetyl groups locating on galactose residues position 2 were also iden- tified and the content was 3.8％. The ^(13)C NMR spectrum and CrO_3 oxidation of TSA indicated the Rhamnose, Arabinose and Galactose to be in α-, α- and β-configurations, respectively. Me- thylation analysis, periodate oxidation, partial hydrolysis and ^(13) C NMR. spectrum showed that TSA. is a branched galactoarabinan.
