Studies On Separation And Purification Of Polysaccharides From Gastrodia Elata Blume & Their Physicochemical Properties

In this paper, we mainly studied on Separation and Purification of Polysaccharides from Yunnan Wild Gastrodia elata Blume and their physicochemical properties.The results showed as follows.(1)It has found that temperature was a very significant factor influencing the extraction rate of the water-soluble PGB and extraction time was a significant factor influencing the extraction rate of the water-soluble PGB through single factor experiments and orthogonal experiments.The optimum extraction parameters of WPGB were obtained: 50℃for extraction temperature, 3 hours of extraction time, 1:10 for the ratio of solid to liquid and 80% ethanol concentration and the amount of WPGB was about 9.67% (dry weight).(2)Through the experiments of immersion the residue which do not dissolve in water respectively by 0.1, 0.2, 0.5 mol.L^-1NaOH solution, we has found that Alkali -soluble PGB content less. The low Yield of APGB is not conducive to cany out further in-depth study, so it was not studied in the experiments.(3)Three WPGB components were isolated from Gastrodia elata Blume with water extraction, alcohol sediment, Sevag deprotein, DEAE-52 column and Sephadex G-100 column.WPGB-Water elution part1 (WPGB-W1) and WPGB-Water elution part2 (WPGB-W2) were non-acidic components, and WPGB-W1 was more hydrophilic than WPGB-W2. WPGB-Alkali elution part (WPGB-A) was acidic component. Focused collection the acidic components (WPGB-A), and proceed to the next stage of Sephadex G-100 column, WPGB-A-H isolated and WPGB-A-L, WPGB-A-H's purity were identified by high-performance liquid chromatography and Sephadex G-100 gel column and a rate of 0.824% (dry weight).(4)Identification of qualitative chemical reaction showed WPGB-A-H were pure neutral polysaccharides ,no proteins, nucleic acids, uronic acid, non-starch ,its average molecular weight was 28,840 Dal. The specific Rotation of WPGB-A-H is [a]²²_D = +206.3(C=0.003, H₂O). The specific Rotation and IR Scanning of WPGB-A-H and proved that WPGB-A-H Europium-D-glu-cose, the sugar ring configuration of pyran-type. Paper chromatography and gas chromatography analysis showed WPGB-A-H contained the D-glucose and D-mannose two monosaccharide components. According to the components of peak area, we can know that WPGB-A-H more of D-glucose and D - mannose less.The experiment has comprehensive studied on separation efficiency, yield and purification process of polysaccharides from Gastrodia elata Blume.It provided us a detailed process line purified polysaccharide from Gastrodia elata Blume.Then we studied on their physicochemical properties. As a theoretical reference for the development and production of polysaccharides from Gastrodia elata Blume, it also helps all aspects of the in-depth study of polysaccharides from Gastrodia elata Blume.