Structural characterization of a polysaccharide from Chrysanthemum morifolium flowers and its antioxidant activity.

The flowers of Chrysanthemum morifolium were extracted by boiling water, and a water-soluble polysaccharide (CMJA0S2) with a molecular weight of 6.5 kDa was isolated by anion-exchange chromatography on a DEAE-cellulose column and gel permeation chromatography on a Sephacryl S-300 HR column. Monosaccharide composition analysis indicated that CMJA0S2 was composed of galactose, glucose, mannose and arabinose in molar ratio of 4.1: 3.3: 1.0: 2.3. According to linkage analysis, partial acid hydrolysis and NMR spectra, the backbone was shown to contain 1, 4-linked β-Gal p , 1, 4-linked β-Glc p and 1, 4-linked β-Man p , with branches substituted at C-6 of 1, 4-linked β-Man p by 1, 6-linked β-Gal p and at O-6 of partial 1, 4-linked β-Gal p substituted by T-linked α-Glc p . About 40% of 1, 6-linked β-Gal p with T-linked α-Glc p was substituted at O-3 by α-Ara f -(1 → [5)-α-Ara f -(1] 3 . The anti-oxidative analysis showed that CMJA0S2 could scavenge the DPPH radicals and relieve the damage of PC12 cells caused by H 2 O 2 , thus it could be regarded as a potential natural antioxidant. [ABSTRACT FROM AUTHOR]