Potential antibacterial and antioxidant properties of a sulfated polysaccharide from the brown marine algae Sargassum swartzii

摘要

AIMS:Sulfated polysaccharide extracted from the brown algae Sargassum swartzii was studied for antioxidant potential.METHODS:The extracted sulfated polysaccharide was analyzed for physico-chemical characteristics,TAC,reducing power,free radical scavenging potentials (DPPH,ABTS,H2O2 radical) and antibacterial properties.RESULTS:The extract showed a high percentage of carbohydrate (7.40 ± 0.63) ％,followed by sulfate (5.3 ± 1.54) ％.The highest antioxidant activity was observed in ABTS (55 ± 3.61)％,followed by H2O2 (47.23 ± 2.81)％ and DPPH (25.33 ± 2.52) ％; significant differences were observed at (P ≥ 0.05).Among the ten human pathogenic strains tested,E.coli was the more sensitive.The characterization and mobility of the sulfated polysaccharide was examined by the FT-IR spectrum and assayed by agarose gel electrophoresis which showed highest mobility at higher pH buffer in carbonate-bicarbonate (pH 10) buffer.The molecular weight of the sulfated polysaccharide was determined by gradient PAGE and was found to be 50 KDa.Finally,GC-MS analysis revealed the presence of peaks corresponding to dimethyl-4-nitroaniline (26.34％).CONCLUSIONS:It is suggested that the sulfated polysaccharide from Sargassum swartzii could be a better source of natural antioxidant,as well as an antibacterial agent.