Study On Extraction, Purification Polysaccharide And Ursolic Acid From Chestnut Flower And Its Properties

More and more studies suggest that the Chinese chestnut not only contains abundantpolysaccharide, ursolic acid, flavonoids, tannins, proteins and so on, but also hasextensive effects on pharmacological properties, such as sedative, anti-inflammatory,antibiosis, fight ulcer and treat diabetes. A new research has found that ursolic acid hasalso influence on anti-tumor. Therefore, extracting polysaccharide and ursolic acid fromplants has become a hot research topic.Microwave assisted extraction was established to extract the polysaccharide andursolic acid in Chinese chestnut flowers, and the effects of microwave extraction time,microwave power, solid-liquid ratio and the concentration of ethanol were also examined.The optimum conditions for single-factor test are microwave time16min, microwavepower150W, the ratio of solid to liquid1:35g/mL and ethanol concentration60%,respectively. The orthogonal experiments were designed based on the conditions of singlefactor and confirmed the influence of various factors on the two substances. The resultsare microwave time>solid liquid>ethanol concentration>microwave power, the influencesequence of polysaccharide is ethanol concentration> microwave power> microwavetime> solid liquid. According to the factors of extraction conditions and finallycomprehensive balance, the optimum process conditions for extract the polysaccharideand ursolic acid in Chinese chestnut flowers are microwave time15minutes, microwavepower150W, solid-liquid ratio of1:35g/mL and the concentration of ethanol of being55%. Under such condition, the extraction yield of polysaccharide and ursolic acid are83.27%and85.48%, the purity are9.31%and7.59%respectively.The purification of polysaccharide and ursolic acid in Chinese chestnut flowers hasbeen researched. Using the water-insoluble property of ursolic acid could achieve theinitial separation between polysaccharide and ursolic acid. The loss rate ofpolysaccharide is1.85%and the purity increases from9.31%to17.66%, while the lossrate of ursolic acid of3.43%and the purity can achieve22.4%. Adopting the methods ofSevage deproteinization, ethanol precipitation combined with metal impurities can purifypolysaccharide. Sevage method can make the purity of polysaccharides enhance from17.66%to47.6%. Comparison of FeCl3and CuSO4methods to remove impurity effect,the results shows that FeCl3enables the purity increase to51.55%, while CuSO4can beup to69.35%. After chloroform extraction, the fineness further enhances to80.11%.Using the NaOH method to eliminate the polyphenol, the purity can reach97.61%afterhydrothermal reactions, which ultimately achieve the separation and purification ofursolic acid.Monosaccharide compositions of polysaccharide and ursolic acid in Chinesechestnut flowers can be measured by HPLC method for qualitative analysis. It indicatesthe polysaccharide is composed of glucose, xylose and arabinose, accounting for52.71%,10.58%and36.71%, respectively. Moreover, the polysaccharide's solubility has beeninvestigated, showing that the polysaccharide is not starchy material, and the purifiedpolysaccharide doesn?t contain the components of protein and amino acid.