Research On The Structures And Hypoglycemic Effect Of Artemisia Seed Polysaccharide

Artemisia seed polysaccharide(ASP), because of its prominent advantages such as strong hydroscopicity — it can absorb 60 times water as the weight of itself, and the high viscosity — which is 1800 times that of gelatin, can be applied widely in different fields, such as chemical industry, food industry and ecology. However, there is no report of its structure analysis in domestic and abroad until now.1. As reported in 1980, the ASP, which was hydrolyzed by H₂SO₄ and acetyl, was analyzed by PC and Whatman celluose column chromatography. The result showed that ASP was composed of D-Glu, D-Gal, D-Man, L-Ara and D-Xyl. In present study, the acetate derivatives of ASP was determined by means of PC, GC, and GC-MS. ASP liquid hydrolyzed by TFA was analyzed by HPLC and IC, the result showed that, besides of the five monosaccharide as reported, we discovered the sixth monosaccharide—D-Lyx. That is to say, ASP is composed of six monosaccharide, the six monosaccharide are L-Ara, D-Xyl, D-Lyx, D-Man, D-Glu and D-Gal.The molar ration is 1:5:2:28:4:14 respectively.In my study, the physical characteristics of ASP are measured firstly by means of light scatterometer, autopolarimeter and thermoanalyzer. The molecule weight of ASP is 1.42×10⁵g/mol, the specific rotatory power is +90°, and the total content of ASP is 96.5%. The thermal analysis shows that ASP is a amorphism powder.2. The sequence of monosaccharide-linker, the classification of glycosidic bonds and the branches points are analyzed by IR, GC, MS, GC-MS, ¹³C-CP/MAS NMR, ¹³C-NMR, ¹H-NMR, ¹³C DEPT135 NMR, 2D NMR (¹³C-¹H COSY and ¹H-¹H COSY) and the ASP are catalyzed by the specific glycosidase for the first time. The results demonstrated that the sequence of monosaccharide-linker is Glu (α-1) - Man(β-1, 3) -Glu (β-1, 4) -Xyl (β-1, 3) -Lyx (β-1, 5) -Glu ( β-1, 4) -Man(β -1, 3, 6) -Gal (α-1, 2, 6) -Gal (β-1, 6) -Xyl (β-1, 3) -Ara (α-1) .Themajor branches point is a-Glu(l-6). All Mans are linked in the way as α-1, 2, 6,β -1,3, 6, and β-1, 2, 3, 6, and all Gals are linked in the way as α-1, 2, 4, 6 ,α-1, 2,6. There are many minor branches in the links.3. The images of ASP were studied by means of AFM and TEM for the first time. The research indicated that ASP is a linear macromolecule with many divisions; thediameter of a monosaccharide molecule is about 1.2- 2.53nm, the chain length is about 2435-8560nm, and the branches length is about 200-2000nm. The three-dimensional network structure can be formed by the entanglement and cross-links among the main strains, the branch strains, and the main strains with the branch strains.4. Using the modern pharmacological method, we studied the hypoglycemic influence and mechanism of ASP on blood sugar, serum insulin, serum glucagons, and hepatic glycogen of the alloxan-induced diabetic rats. The results demonstrated that ASP could reduce hyperglycemia, change glucose into glycogen; recover the destructed pancreatic cell, Enhance the physical antioxidant function and protect the hepar and kidney.