Extraction, Isolation, Purifcation And Structure Probe Of Polysaccharide From Radix Rehmannia Preparate

Rehmannia glutinosa polyses(RGP) exists particularly in Radix Rehmannia Preparate,which not only is food ,but is chinese tradtional medicine.Pharmacological investigations indicated RGP can resist tumor,adjust immunity,increase blood and so on.To study the extracting technology of and purification and structure are important to deeper the process of Radix Rehmannia Preparate and the development of functional food and medicine of RGP.This paper based on studying hot extracting of RGP, the supersonic was applied to strengthen the extraction and the supersonic extracting was optimized using response surface methodology. The crude polysaccharides were isolated and purified by chromatographying with SephadexG-200 and DEAE-Sepharose column. During the structure analysis of RGP, purity and component sugars were carried out by UV, IR, TLC.The extracting test showed that the best hot extracting technology of RGP was that:the particle of 40 mesh size;extraction temperature90℃sample ratio : solvent=1:70(m/V);extraction time 2h , the extracting rate is 6.679%.Supersonic extracting can improve the extracting rate and reduce the extracting time and simplify the extracting process. The better supersonic extracting technology was that: the particle of dried Radix Rehmannia Preparate 40 mesh size;sample ratio : solvent=1:56(m/V); extraction time 3.1min and extraction temperature 64.5℃. The extracting rate is 6.801%. After regression analysis , factors which influenced response variables significantly new selected. Consequently multinomial regression equation was obtained: y=6.6463+0.304x1+0.1415x2+0.212x3-0.061x1x2-0.2872x1x3-0.0815x2x3-0.2527x12+0.0665x22-0.2727x32The separation and purification technology of RGP test showed: The extracting solution of RGP concentrated by vacuum rotary evaporator, then eliminated protein using sevage reagent and dialysed by distilled water. When ethanol of certain concentration added, many white deposit were formed. Then the deposit dried by vacuum freeze drier. The crude polysaccharides were isolated and purified by chromatographying with SephadexG-200 and DEAE-Sepharose column. DEAE-Sepharose column had a higher partition rate. During the purification process, DEAE-Sepharose column had more adsorption for pigment than SephadexG-200 column. Therefore, DEAE-Sepharose column was chosen for the purification of RGP.Composition analysis of Rehmannia glutinose Polysaccharides was studied. The TLC method was established to analysis composition of Rehmannia glutinose Polysaccharides Silica gel plate, n-butanol : HAc : H2O (9:4:2) as developing solvent, 10%sulfuric acid-ethanol eoloration. Rehmannia glutinose Polysaccharides was composed of galactose, glucose, fructose and stachyose.