Separation, Purification And Antibacterial Activity Of Polysaccharides And Flavones From Purslane

Purslane is widely grown in China,it is one of the wild plants changbai mountain. Purslane contains a variety of nutrients, at the same time also has a variety of biological activity, such as antibacterial antibacterial, antitumor, anti-aging, antioxidant and fall hematic fat, etc. In addition, Purslane has the characteristics of wide sources, low cost and fast growth. So people begin to study the bioactive components of Purslane. Polysaccharides and flavonoids of Purslane play an important role in its bacteriostasis. This study based on the separation, purification and antibacterial activity of polysaccharides and flavones in Purslane. This study laid the foundation for further utilization of the natural preservative bacteriostasis research.In this study, the polysaccharides and flavonoids from Purslane were extracted by ultrasonic method. The polysaccharides content was measured by the phenol–sulfuric acid method using glucose as the standard. The flavonoids content was measured by the colorimetric method using rutin as the standard. By the results of single factor experiments, four factors three levels orthogonal test was selected. The results showed that the yield of polysaccharides was 5.42% under the optimal conditions of 60℃, 60 min, 1:20 and 200 W. The results showed tha the yield of flavonoids was 3.61 % by ultrasonic method under the optimal conditions of 50℃, 40 min, 1:25 and 200 W.The crude polysaccharides were collected and purified by DEAE-Cellulose anion-exchange and Sephadex gel-permeation chromatography. Three fractions were obtained and named POL1, POL2 and POL3, respectively. The molecular weights of these three fractions were measured by Sephadex using dextran standard curve. Escherichia coli, Acetic acid bacteria, Saccharomycetes and Aspergillus Niger were used to study the antibacterial activity of the polysaccharides. Molecular weights of POL1 a, POL2 a and POL3 were 18 Kd, 108 kd and 55 kd, respectively. The inhibition diameters of POL2 a were 16.33mm(Saccharomycetes), 15.10mm(Acetic acid bacteria), 14.20mm(Aspergillus Niger) and 12.93mm(Escherichia coli.). The inhibition diameters of POL3 were 15.40mm(Saccharomycetes), 14.03mm(Acetic acid bacteria), 12.60mm(Aspergillus Niger) and 11.17mm(Escherichia coli). The inhibition diameters of POL1 a were 14.03mm(Saccharomycetes), 13.17mm(Acetic acid bacteria), 11.97mm(Aspergillus Niger) and 10.40mm(Escherichia coli). It could be concluded these three fractions had inhibitory effect on Saccharomycetes, Acetic acid bacteria, Aspergillus Niger and Escherichia coli. The polysaccharides had inhibitory effect on microorganisms, and the inhibited order of microorganisms was: Saccharomycetes>Acetic acid bacteria>Aspergillus Niger>Escherichia coli.The crude flavonoids were collected and purified by macroporous absorption resin. Escherichia coli, Acetic acid bacteria, Saccharomycetes and Aspergillus Niger were used to study the antibacterial activity of the flavonoids, the flavonoids was pure after purified by macroporous absorption resin using 70% ethanol. The inhibition diameters were 14.23mm(Saccharomycetes), 12.93mm(Aspergillus Niger), 12.00mm(Acetic acid bacteria) and 11.37mm(Escherichia coli). The inhibitory effect on microorganisms, the inhibited order of microorganisms was: Saccharomycetes > Aspergillus Niger > Acetic acid bacteria >Escherichia coli.