Isolation,Purification,structural Elucidatuion And The Applied Research Of Polysaccharides From Wedlia Prostrata

Dendrobium appeared in China very early in the record.Dendrobium officinale Kimura et Migo is orchid genus perennial herbs.Its stem has a high medicinal value about the digestive system、respiratory system problem and enhance the heart rate.Because of the hard growth conditions,the research is mainly focus on the expanding culture-based.The material of other studies what is study medicinal value is from Yunnan,the study of Dendrobium officinale which is from Zhejiang is seldom,the in-depth study is less.This article is divided into several aspects of Dendrobium officinale polysaccharide has carried on the comprehensive research:Dendrobium officinale polysaccharide extraction and antioxidant activity of polysaccharides,the separation and purification of polysaccharide from Dendrobium officinale and the preliminary appraisal of the structure,application research of the polysaccharides from Dendrobium officinale.After alcohol precipitation DOP30,DOP60 and DOP80 were obtained.Through the antioxidant activity and sugar content,this article makes an in-depth study of DOP60 and DOP80.Two water-soluble homogeneous polysaccharides DOP60A and DOP80A were purified and obtained by using DEAE Sepharose fast flow anion-exchange chromtography and Sephacryl S gel-filtration chromatography from DOP60 and DOP80.HPLC producing a single symmetrical peak indicated each of them was homogeneous and their molecular weight were 1.3×104 Da and 1.2×104 Da.Lack of absorption at 280 nm and 260 nm by UV scanning indicated that they contained no protein and nucleic acid.The infrared spectrum of DOP60A displayed a broad stretching intense.characteristic peak of fructan.Sugar compositional analysis of DOP60A was determined by GC.Comparison with the analysis of mannose and glucose standard showed that DOP60A was composed of mannose and maybe little glucose.The structure of DOP60A was further investigated using Methylation analysis and NMR spectroscopic methods(1H NMR,13C NMR and 2D NMR).The applied research of DOP mainly focus on two sections:research on anti-tumor activity of DOP indicates it possesses anti-tumor activity and has small side effects;the study on the application of cigarette showed:DOP plays a good moisturizing effect on S180 and A549.It can reduce the loss of tobacco moisture,improve the comfort of smoking and be used as a new kind of tobacco humectant.