Study Of The Primary Structure And Observing Of Microstructure Of The Polysaccharide Isolated From Cortex Of Paeonia Ostill(Moutan)

A water soluble polysaccharide has been isolated from cortex of PaeoniaOstill(Moutan). The crude polysaccharide was deproteinized by freezed-meltedmethod repeatedly, and fractionated by DEAE-52 and molecular sieve, giving twopolysaccharide fractions termed PSM-2bA and PSM-2bB respectively.Homogeneity of them were proved by HPLC. GC-MS show that PSM-2bA consistsof Rha, Ara, Xyl, Man, Glc and Gal with the molarity rate of 3.55: 7.06: 2.11:1.00: 5.60: 12.91 in turn and PSM-2bB consists of Rha, Ara, Xyl, Man, Glc andGal with the molarity rate of 3.43: 8.05: 1.00: 1.00: 24.94: 9.01 in turn.The polysaccharide contents of PSM-2bA and PSM-2bB measued by phenol-sulphuric acid method were 91.8%,82.6%, respectively, and protein contents were2.7%,1.3% measured by coomassie brilliant blue method and uronic acids were4.2%,15.2% measured by sulfate-3-phenylphenylol method. These indicated thatPSM-2bA and PSM-2bB were a kind of acidic heteropolysaccharides. In the structureanalysis of PSM-2bA and PSM-2bB, ¹³C-NMR, partial hydrolysis with acid, periodateoxidation, Smith degradation, IR, GC-MS and methylation etc. were the principalmethods used. After acetylation, the methylated productions were analyzed by GC-MS. The results revealed that PSM-2bA and PSM-2bB both were a kind of highbranched structure. Meanwhile PSM-2bA was some kind of structure with lots ofdivarication at main-chain and small branch; The possible main chain unit of PSM-2bA was The microstructure of PSM-2bA was studied by Congo Red, TEM and ESEM.And the conclusion was deduced that the microstructure of PSM-2bA was somethinglike network which formed by helical structure composed by sub-particle. The naturestate of PSM-2bA was band shape.The thesis also investigated the reduction-acetylation conditions ofmonosaccharides basing on it's importance to the analysis by GC or GC-MS. Thederivatives of 5 kinds of monosaccharides Xyl, Ara, Man, Glc, Gal were detected anddetermined respectively by GC-MS. The influences of several factors, such asreductive time, reductive temperature, acetylating temperature and acetylating time,on recovery of monosaccharides were studied by orthogonal experiments. The resultsshowed that the reductive temp. and the acetylating time influences derivatizationsignificantly. The optimal derivatization condition is reducting reaction 2.5h at 50℃followed by acetylating 2.5h at 90℃.