Study On Extraction, Purification And Antioxidant Activity Of Polysaccharides From The Leaves Of Bruguiera Gymnorrhiza

Bruguiera gymnoihiza (L) Savigny. is a Sect.Rhizophoraceae, Bruguiera. Which is one of dominant tree species in Chinese mangrove. Bruguiera leaves are rich in a variety of compounds such as Fatty acid, Amino acids, Polysaccharide, Flavonoids, Terpenes and so on. It had recorded that Bruguiera gymnoihiza (L.) Savigny. could antifebrile agen,diarrhea and cooling blood, bactericidal anti-inflammatory as early as in folk Pharmacology. On the other hand, the Polysaccharide was widely present in fauna, flora and each microorganisms organization, which was a kind of very necessary basic material of life activities. The Polysaccharide in the Bruguiera leaves was raw materials in the topic, which were researched by ultrasonic extracted, purification technology and the antioxidant and antiallergic, in order to fill the gaps in the study of Bruguiera leaves, was provided a theoretical basis for further systematic research and rational development and utilization of mangrove resources. The main content of this paper was as follows:It used the phenol-sulfuric acid method to determine the Polysaccharide contents in the Bruguiera’s leaves. After the choices of the absorption wavelength of the stability test, recovery test, repeatability test, it proves the determination of phenol-sulfuric acid method was applicable determination the polysaccharide contents in the Bruguiera’s leaves. And it had proved this method is easier, faster,more accurate and reliable than others also.Be used the Heat extraction with ultrasonic-assisted to study the single factor tests such as extraction power, extraction time, extraction temperature and solid liquid ratio about Bruguiera’s leaves. On the basis of the single factor statistical analysis tests’data,the Orthogonal test was planed. It was found that the optimum technological conditions of these studies were obtained as follow:solid liquid ratio was1:50, extraction power was350W, extraction time was15min and extraction temperature80℃.Under the best technological condition, the rate of polysaccharide extraction of the Bruguiera’s leaves was17.35%.Checking the effect of deproteinization, macroporous resin decolorization about Bruguiera gymnoihiza, got some studies of alcohol precipitation conditions and purified by DEAE-52cellulose column chromatography. The result of research proved that:the rate of protein removal by Sevag can be reached to60.1%. Polysaccharide retained can be reach to75.4%. both of the rates have reached more than80%with Macroporous resin S-8, which the effect is better than types AB-8,DM130and D101. The best effect alcohol precipitation condition was that the ethanol concentration reached to90%, concentration ratio of the sample solution was1:2and the PH was prototype liquid. After the cellulose column chromatography of type DEAE-52and eluting by distilled water and NaCl eluent, and two fractions of polysaccharides were obtained, named as Y1and Y2.After researching the refined polysaccharide of Bruguiera gymnoihiza leaves about the reducing power,·OH, O2-and the DPPH scavenging power. The results show that:The reducing power is increasing while the concentration increased. When the concentration reach to8mg/ml, O2-scavenging rate was34.5%, the DPPH·scavenging rate was41%, OH-cavenging rate was59.5%.The polysaccharide of Bruguiera’s leaves which had been purified were detected by Physical observation, color reaction,UV absorb spectrum and infra-red spectrum, it was in order to evaluate the nature of the polysaccharide. FT-IR spectrograph analysis showed that:After purifying, there was no protein in Y1or Y2. It was main of β-pyranose glycosidic bond in Y1. And Y1demonstrated characteristic absorption peak as pyranose, which had the Pyranose ring structure also, but Y2did not have Pyranose ring structure. It needs to be further studied to determine Polysaccharide molecular weight and monosaccharide compositions.