Extraction,Isolation,Purification And Antioxidant Activity Of Polysaccharide From Tilia Amurensis Rupr.Flower

Tilia amurensis Rupr. is an important tree species with high economic value and it’s one kind of tall deciduous arbor,which belongs to Tiliaceae and Tilia.Tilia amurensis Rupr. flower contains abundant polysaccharide,which makes it an ideal plant polysaccharide resource with significant research value.In this paper,the extraction process,isolation,puriflcation and antioxidant activity in vitro and in vivo of polysaccharide extracted from Tilia amurensis Rupr. flower were studied systematically in order to provide new direction and reference for comprehensive development and utilization of Tilia amurensis Rupr. resource in China. The experiment items and results are stated as follows:Study on the optimization of extraction process of polysaccharide in Tilia amurensis Rupr. flower. With the yield of polysaccharide from Tilia amurensis Rupr. flower as index, microwave-assisted method and enzymatic auxiliary extraction were used to optimize the extraction process of polysaccharide from Tilia amurensis Rupr. flower. The results showed that the yield of polysaccharide extracted by microwave-assisted method was higher, which could reach12.57%. The optimum process condition was microwave time9.14min,microwave power585W, and ratio of raw material to liquid1:67(g:mL).Study on physical and chemical properties and antioxidant activity in vitro of crude polysaccharide from Tilia amurensis Rupr. flower. Fundamental physicochemical properties of crude polysaccharide from Tilia amurensis Rupr. flower were analysed through some chemical reactions such as phenol-sulfuric acid reaction, the Fehling reagent reaction and so on. The conclusion was obtained that polysaccharide from Tilia amurensis Rupr. flower had common properties of polysaccharide. By the way, total polysaccharide content in crude polysaccharide from Tilia amurensis Rupr. flower determined by phenol-sulfuric acid reaction was65.28%and uronic acid content determined by sulphuric acid-carbazole method was39.25%. Spectrum analysis indicated that polysaccharide extracted from Tilia amurensis Rupr. flower had typical polysaccharide characteristic absorption peaks. The antioxidant experiments in vitro declared that polysaccharide from Tilia amurensis Rupr. flower had reducing power, scavenging capacities on1,1-diphenyl-2-picrylhydrazyl radical and hydroxyl free radical and the inhibition effect on lipid peroxidation induced by ferrous ion. With the concentration reaching up to1.8mg·mL-1, the scavenging rate on hydroxyl free radical was88.19%and the inhibition rate on lipid peroxidation reached75.42%when the polysaccharide concentration was2.0mg·L-1which was appreciably higher than ascorbic acid of the same concentration.Study on the the antioxidant activity in vivo of crude polysaccharide from Tilia amurensis Study on the the antioxidant activity in vivo of crude polysaccharide from Tilia amurensis Rupr. flower. the antioxidant activity in vivo of crude polysaccharide from Tilia amurensis Rupr. flower was investigated through the establishment of D-galactose induced mice aging model. Results showed that the crude polysaccharide from Tilia amurensis Rupr. flower could significantly improve the T-SOD activity in liver tissue and GSH-PX activity in serum of aging mice, and significantly reduce the MDA content in serum, liver tissue and brain tissue of aging mice at the same time. MDA content in serum of mice in low, medium and high dose group and that in brain tissue of mice in middle and high dose group had extremely significant difference compared with model group, which showed that crude polysaccharide from Tilia amurensis Rupr. flower had good antioxidant activity in vivo.Separation, purification and characterization analysis of polysaccharide from Tilia amurensis Rupr. flower. Further purification of TAP was operated by means of DEAE-52cellulose and three purified polysaccharide components were obtained, which were respectively named TAP-1, TAP-2and TAP-3, among which the content of TAP-3was the most. Thus, intensive study was mainly on TAP-3component. Ultraviolet (UV) spectral scanning, freezing and thawing analysis and high performance gel permeation chromatography (HPGPC) were used to identify the purity of TAP-3, determining that TAP-3was uniform polysaccharide component without nucleic acid nor protein. Infrared spectroscopy (FT-IR), HPGPC and GC-MS were used to analyze the structure characterization of TAP-3. The relative molecular mass of TAP-3was5376Da and it was heteropolysaccharide consisting of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose and themoore ratio of the seven monosaccharides was0.76:23.28:15.02:15.87:3.44:3.33:24.59.