Study On Extraction,Basic Structure And Membrane Separation Of Polysaccharide From Dictyophora Rubrovolvata

Objective:The ultrasonic assisted extraction process of polysaccharide from Dictyophora rubrovolvata was optimized to improve the extraction rate of polysaccharide.The structure characterization and component analysis of polysaccharide from Dictyophora rubrovolvata were carried out to provide design basis for membrane separation process.The laboratory purification of polysaccharide by membrane separation was established,which provided technical support for the industrialization development of Dictyophora rubrovolvata polysaccharide.Methods:Dictyophora rubrovolvata in Zhijin Guizhou was used as raw material for ultrasonic-assisted extraction.The ultrasonic power,ultrasonic time,extraction frequency and solid-liquid ratio were optimized by Box-Behnken design.Sevage method was used to remove protein from Dictyophora rubrovolvata polysaccharide,and the polysaccharide component SV-PDR was obtained.The molecular weight and distribution of SV-PDR polysaccharide were determined by HPGPC and SEC-MALLS,the monosaccharide composition was determined by PMP-HPLC,the glycoside bond was determined by periodate oxidation,Smith degradation and methylation test,the configuration and functional group vibration were determined by FT-IR and NMR,and the morphology of the polysaccharide was observed by SEM,Finally,the basic structure of SV-PDR polysaccharide was determined.And the composition of polysaccharide extract of Dictyophora rubrovolvata was analyzed.The data were used as the basis for membrane separation experiment design.Membrane separation technology was used to separate and purify polysaccharide from Dictyophora rubrovolvata.HPS-100 ultrafiltration membrane was used to compare the effects of alcohol precipitation,membrane separation,and membrane separation+alcohol precipitation technology on the separation of polysaccharide from Dictyophora rubrovolvata.The cleaning effects of different cleaning solvents on HPS-100 ultrafiltration membrane were also investigated.Results:The optimal ultrasonic extraction parameters of polysaccharide from Dictyophora rubrovolvata were as follows:ultrasonic power was 480 W,ultrasonic time was 35 min,extraction frequency was 2,ratio of solid to liquid was 1:20 g/m L.Under these conditions,the extraction rate of polysaccharide was 14.55%,and the polysaccharide content was 60.33%.SV-PDR was obtained by Sevage method.The content of polysaccharide was 94.37%.The molecular weight of SV-PDR was 3.005×10~6Da and the absolute molecular weight was 3.448×10~6g/mol.It was mainly composed of mannose,glucose and galactose with the molar ratio of 10.29?32.71?1.The backbone chain was the following structure:?6)-Glcp-(1?,and side chain of?3)-Glcp-(1?and?4)-Glcp-(1?.SV-PDR were linked by?-configuration and?-configuration,which was a pyran ring polysaccharide with three-dimensional spiral structure.On the basis of ultrasonic extraction process,membrane separation experiment was carried out.The purity of Dictyophora rubrovolvata polysaccharide was effectively improved by membrane separation combined with alcohol precipitation technology,and the polysaccharide content was increased to 71.73%.In addition,1%HCl cleaning solution can restore the ultrafiltration membrane flux to 83%.Conclusions:The ultrasonic extraction process of polysaccharide from Dictyophora rubrovolvata was established with the extraction rate of 14.55%,which improved the extraction rate of polysaccharide in the study.The backbone chain was the following structure:?6)-Glcp-(1?,and side chain of?3)-Glcp-(1?and?4)-Glcp-(1?.SV-PDR were linked by?-configuration and?-configuration.The membrane separation process of Dictyophora rubrovolvata polysaccharide was established,and the polysaccharide content was increased to 71.73%.