Preliminary Study On Extraction,Separation, Molecular Structureand Bioactivities Of Polysaccharides From Phyllanthus Urinaria L.

Objective:Extract and isolate polysaccharides from Phyllanthus urinaria L.(PUL); Study on the purification of polysaccharides, the structure of polysaccharides, and biological activity. It will lay the foundation for pharmacodynamic material basis for clinical application and mechanism of action of PUL.Methods:(1) Classical hot water extracting and ethanol precipitating method was used to extract polysaccharides from Phyllanthus urinaria L and DEAE-cellulose chromatography was used to separate crude Phyllanthus urinaria L polysaccharides (PULP). Finally, SephadexG-200 and HPLC were used to prove the homogeneity of crude PULP.(2) Anti-oxidative effect of PULP was studied from three aspects of reducing power, H2O2/Fe2+ system and LPO system.(3) Using chemical methods (such as physical and chemical properties,acid hydrolysis, partial acid hydrolysis, periodate oxidation and so on) and IR, GC, HPLC and other modern chromatography, spectroscopy, the structural characteristics of homogeneous polysaccharide was investigated.Results:(1) After extracting with distilled water and precipitated with ethnol and getting rid of protein with Sevag’s method, the content of polysaccharides of PUL is 28.27%.(2) The crude polysaccharides which were named as PULP, PULP â…¡, PULPâ…¢ and PULP â…£ were fractionated by column chromatography DEAE-52 and PULP â…¡ and PULPâ…¢ were obtained.They were proved to be homogeneous polysaccharide on molecular weight by SephadexG-200 chromatography and HPLC.(3) The results of vitro antioxidant experiment suggested that PULP â…¡ and PULPâ…¢ have good anti-oxidation action;and the reducing activity, the scavenging capacity for .OH and the eliminating capacity for LPO were enhanced as PULP â…¡ and PULPâ…¢ concentration was inceased.(4) The physical and chemical properties part of PULP â…¡ and PULPâ…¢ showed that the contents of uronic acid are 8.37% and 45.1%;the element analysis showed that N and S are absent, they are not a aminosugar; the average molecular weight of PULP â…¡ and PULPâ…¢ are 579962.6 and 418793.5.(5) The preliminary analysis of structure of PULP â…¡ and PULPâ…¢ showed that PULP â…¡ is constituted of Rha, Ara, Man, Glc, with the molarity rate of 0.11:0.37:0.08:0.45; PULPâ…¢ is constituted of Rha, Ara, Man, Glc, with the molarity rate of 0.27:0.28:0.1:0.35. PULP â…¡ is constituted of Rha, Ara and Glc and the backbone of PULP â…¡ is constituted of Rha, Ara, Man and Glc. PULPâ…¡and PULPâ…¢ have the same glycosidic bond which most of them is 1â†'6 glycosidic bond, rarely linked by 1â†'4 and 1â†'3 glycosidic bond.