Studies On The Extraction And Quality Determination Of Lycium Barbarum Polysaccharide

Lycium barbarum has a high nutritional and medicinal value.Polysaccharide is the main active ingredient in Lycium barbarum and it has important research significance and extensive applied prospects.In this paper,we have investigated the extraction and quality determination methods,and analyzed the monosaccharide composition.The main contents are as follows:In the introduction,we mainly summarized the extraction,separation and content analysis of polysaccharides.The quality determination standards of polysaccharides were also reviewed.Then we described the theoretical background and research progress related to Lycium barbarum polysaccharide.Finally,we put forward the significance and research content of the present thesis.In the second chapter,we investigated the extraction process of Lycium barbarum polysaccharide.Through the single factor experiment,orthogonal experiment design and analysis of variance with the key factors in the extraction process of Lycium barbarum polysaccharide,the optimal extraction process of Lycium barbarum polysaccharide by water extraction and alcohol precipitation was screened out:The ratio of-solid to liquid is one to fifteen(volume ratio),the leaching temperature was 95°C,the leaching time was 3 hours and the leaching times was once or twice.The yield of Lycium barbarum polysaccharide was 2.54%,and the polysaccharide content of Lycium barbarum polysaccharide was 43.32%.We also enlarged the extraction process and applied it to extraction of different regions of Lycium barbarum dried fruit.The third chapter described the quality determination methods of Lycium barbarum polysaccharide.The mothod of thin layer chromatography(TLC)was established for qualitative identification of Lycium barbarum polysaccharide in monosaccharide contents and quantity.By screening elution programs,flow ratse and other chromatographic conditions,the high performance liquid chromatography(HPLC)specific chromatogram of Lycium barbarum polysaccharide was established by using glucose as the reference substance.By comparing the relative retention times of the mixed standard chromatograms with the established HPLC specific chromatograms and the standard substance addition method,characteristic peaks were identified.The seven characteristic peaks were:mannose,rhamnose,galacturonic acid,glucose,galactose,xylose and arabinose.This method could quickly identify monosaccharide composition in Lycium barbarurm polysaccharide.Finally,the quality determination method was applied to different regions and different manufacturers of Lycium barbarum polysaccharide.The fourth chapter was about the quantitative study of six kinds of monosaccharides in Lycium barbarum polysaccharide.According to the conditions of HPLC specific chromatograms of Lycium barbarum polysaccharide,the types and content of monosaccharide in Lycium barbarum polysaccharide were determined.By using the methodological verification,the present method was reliable and applicability.By measuring the content of six kinds of monosaccharides in 10 batches of Lycium barbarum polysaccharide,we got the average molar ratio of six kinds of monosaccharides in Lycium barbarum polysaccharide.Then we measured the molar ratio of six kinds of monosaccharides in Lycium barbarum polysaccharide of 8 batches of different manufacturers,it was found that other polysaccharides with glucose as monomer may be added in two batches.The method provided the basis for the quality determination of Lycium barbarum polysaccharide,which could effectively prevent illegally added behaviors and provide the basis for the quality determination of the Lycium barbarum polysaccharide.It could also provide the basic guarantee for the subsequent analysis of the Lycium barbarum polysaccharide.In the fifth chapter Lycium barbarum polysaccharide(LBP 1)was isolated by DEAE Sepharose Fast Flow column.The monosaccharide composition,neutral sugar content,protein content and uronic acid content of components were determined.