| Polygonatum sibiricum Red.,is well know for its unique medical and edible value.Modern pharmacological studies have shown that P.sibiricum has a variety of biological activities.Therefore,the study on the isolation,purification and structure characterization of P.sibiricum glycopolymers can provide data support for the study of anti osteoporosis mechanism and structure-activity relationship of P.sibiricum glycopolymers.The crude polysaccharides PS50,PS90 and PSB,were obtained from the rhizome of P.sibiricum by water extract and alcohol precipitation or alkali extract and alcohol precipitation.The contents of sugar were measured by phenol sulfuric acid method,and the sugar content were 56.7%,70.6% and 48.4% respectively.Then,the crude glycopolymers PS50,PS90 and PSB were deproteinized by Sevage method and treated by dialysis,concentration and freeze-drying.The samples were further isolated and purified by ion exchange chromatography(DEAE-Cellulose 52)and gel column(Sephacryl S-100).Finally,eight homogeneous glycopolymers PSP90-1,PSP90-2,PSP50-2-1,PSP50-2-2,PSP50-3,PSBP-2-1,PSBP-2-2 and PSBP-3 were obtained.Then,the purify were determined through specific rotation and high-performance gel permeation chromatography(HPGPC)method.The results showed that all homogeneous glycopolymers with the relative molecular weight of 1.2 k Da、1.6 k Da、7.8 k Da、7.1 k Da、17.0 k Da、40.3 k Da 、 12.2 k Da and 10.3 k Da,respectively.The monosaccharide compositions of these eight glycopolymers were analyzed by ion chromatography and PMP precolumn derivatization-high performance liquid chromatography(HPLC).The primary structures of the eight glycopolymers were obtained by Infrared Spectroscopy(IR),Gas Chromatography and Mass Spectrometry(GC-MS)and Nuclear magnetic resonance(NMR)analysis.The results showed that PSP90-1,PSP90-2,PSP50-2-1,PSP50-2-2,PSP50-3,PSBP-2-1,PSBP-2-2 and PSBP-3 are all heteropolysaccharides,and the structures of the eight glycopolymers form the rhizome of P.sibiricum have not been reported.Congo red test and scanning electron microscope were used to analyze the advanced structure of the eight glycopolymers.The results showed that the eight glycopolymers had no triple helix structure,and the surface morphology of the eight glycopolymers was different under scanning electron microscope.Eight homogeneous glycopolymers were studied in vitro to promote bone formation.The results showed that Polygonatum glycopolymers PSP90-1,PSP90-2 and PSP50-2-2 have certain in vitro bone formation promotion activities. |
