Primary structure and configuration of tea polysaccharide.
The monosaccharide composition of a tea polysaccharide (TGC) was determined by GC-MS method. Furthermore, the primary structure of tea polysaccharide and its configuration in the aqueous solution were investigated utilizing a combination of classical chemical methods and modern instrumental techniques including GC-MS, Proton NMR, UV and CD. The results indicate that TGC consists of 6 monosaccharides: Rha, Ara, Xyl, Glu, Man and Gal. The configuration of TGC in water solution is proposed to be an ordered helix. The possible primary structure of TGC was outlined as below: the basic structure of the main chain consists of Rha, Glu and Gal units. All three monosaccharides can potentially be connected to branch chains consisting of mainly Ara, and the linkages could be in beta1 --> 2, beta1 --> 3, beta2 --> 3 forms. When branch chain is absent in the basic structure of the main chain the linkage consists of only beta1 --> 3; Xyl exists at the terminal end of either the main chain or the branch chain with beta1 --> linkage.
Zhou
Peng
P
Key Laboratory of Food Science of Ministry of Education, Nanchang University, Nanchang 330047, China.
Xie
Mingyong
M
Nie
Shaoping
S
Wang
Xiaoru
X
D001671:Biochemistry / Q000379:methods; D002236:Carbohydrate Conformation; D002942:Circular Dichroism; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D009005:Monosaccharides / Q000737:chemistry; D010504:Periodic Acid / Q000737:chemistry; D018515:Plant Leaves / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry*; D013662:Tea / Q000378:metabolism*; D013997:Time Factors; D014466:Ultraviolet Rays
D009005:Monosaccharides; D011134:Polysaccharides; D013662:Tea; D010504:Periodic Acid; C009288:metaperiodate