title: Chemical characteristics and antioxidant activities of polysaccharide purified from the seeds of Plantago asiatica L.
abstract: BACKGROUND
  A water-soluble polysaccharide from the seeds of Plantago asiatica L. (P. asiatica L. polysaccharide, PLP) was extracted with hot water and purified by gel filtration chromatography. The chemical characteristics of PLP were determined by high-performance gel permeation chromatography (HPGPC) and Fourier transform infrared (FTIR) spectroscopy. In addition, the antioxidant activities of PLP in vitro were evaluated using various test systems, including scavenging of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals, scavenging of superoxide radicals generated by 1,2,3-phentriol autoxidation, scavenging of hydroxyl radicals and inhibition of lipid peroxidation.
  
  
  RESULTS
  The molecular weight of PLP was determined by HPGPC to be about 1894 kDa. PLP contained 29.2 g kg(-1) protein and 145.8 g kg(-1) uronic acid. The FTIR spectrum of PLP also revealed typical characteristics of a polysaccharide containing protein and uronic acid. Moreover, the results showed that PLP possessed antioxidant activities, but lower than those of ascorbic acid.
  
  
  CONCLUSIONS
  PLP is an acid protein-bound polysaccharide of high molecular weight, but its structure needs further study. The present results suggest that PLP could potentially be used as a natural antioxidant.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Jun-Yi
authors.initials: JY
authors.lastname: Yin
authors.forename: Shao-Ping
authors.initials: SP
authors.lastname: Nie
authors.forename: Chao
authors.initials: C
authors.lastname: Zhou
authors.forename: Yin
authors.initials: Y
authors.lastname: Wan
authors.forename: Ming-Yong
authors.initials: MY
authors.lastname: Xie
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D002850:Chromatography, Gel; D015227:Lipid Peroxidation / Q000187:drug effects; D008970:Molecular Weight; D010936:Plant Extracts / Q000737:chemistry*; D010940:Plant Proteins / Q000032:analysis; D010943:Plantago / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D012639:Seeds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014574:Uronic Acids / Q000032:analysis
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D010940:Plant Proteins; D011134:Polysaccharides; D014574:Uronic Acids