Crassipes Extraction, Separation And Structure Analysis Of Polysaccharides

Eichhornia crassipes was first introduced from South America into China in1901andwidely planted as pig feedstuff in the1950s. Because of its extraordinary adaptive ability andremarkable growth rate it is regarded as an important and pernicious invasive species whichhas seriously impaired the biological diversity and ecological environment.However, someanalysis indicated that Eichhornia crassipes is a promising plant for using hyperaccumulaorsto treat heavy metal contaminated soil and sewage sludge,it aslo used for feedstuff andpapermaking.Up to date,polysaccharide extraction from Eichhornia crassipes has scarcely ever beenreported. Because Eichhornia crassipes grows quickly, and it contains high amounts ofhemicellulose and cellulose but there have been only a few reports on Eichhornia crassipespolysaccharides and few on its functional effects.So it’s necesssary to extract polysaccharidefrom the stem and leaf of Eichhornia crassipes(ECSP and ECLP).The objective of thisdissertation is to study the isolatin,purification,physical chemistry property, it’s componentand so on. This text aslo made Super Absorbent polymer(SAP)by it’s water absorbability.ObjectiveTo systematically study the polysaccharides from the stem and leaf of water hyacinth clarifythe chemical structure,biological activities,which will provide scientific basis for newpolysaccharide SAP and comprehensive utilization of water hyacinth.Methods1.Extraction,isolation and purification of ECSP and ECLP:Alkali extracting-alcoholprecipitating method was applied to extract crude polysaccharides,after dialysised thenpurified by Sephadex gel chromatography.Purity and molecular weight of every homogeneouspolysaccharide were determined by HPGPC method.2.Structural elucidation of homogeneous polysaccharide:Based on chemicalmethods(including sugar compositin analysis, partial acid hydrolysis)and spectralanalysis(HPLC,LC-MS,IR),the structural characteristics of homogeneous polysaccharide wasinvestigated. 3.Study on the biological function of ECSP and ECLP:Because of their well waterabsorbility,the research demonstrated they can make SAP.The optimal parameters for SAPwere determined by single factor.Results1The primary chemical composition of powder of frozen dried stem of water hyacinthwere: total sugar68%,protein3%, crude fat1.1%, total ash14.3%, solubleash19%,moisture8.9%;the leaf of water hyacinth were: total sugar65.1%,protein8%, crudefat2%, total ash11.9%, soluble ash7.38%,moisture13%.2Polysaccharide from the stem and leaf of water hyacinth were first extracted byalkai treatment.The results showed that the optimum conditions of stem polysaccharidewere:the concentration of NaOH0.3mol/l,time0.5h,temperature40℃,sample/water1:60,times3;leaf polysaccharide were: the concentration of NaOH0.5mol/l,time1h,temperature60℃,sample/water1:60,times3.3Through HPGPC the result showed that ECSP and ECLP were hetetopolysaccharideand the weight of their molecular were862978Da and78860Da respectively.4Through partial acid hydrolysis and coupled with LC-MS the results showed thatECSP had six monosaccharide and they were Man,Glc,Fru,Gal,Xyl,Fuc,and their rationwere1：1.38：11.228：1.205：2.19：11.19；ECLP had six monosaccharide and they wereMan,Glc,Fru,Gal,Xyl,Fuc,and their ration were36.2：45.3：24.5：2.08：20.14：1：20.