Pectic polysaccharides of the fresh plum Prunus domestica L. isolated with a simulated gastric fluid and their anti-inflammatory and antioxidant activities

A pectic polysaccharide, designated as PD, was extracted from fresh plums (Prunus domestica L) with a simulated gastric fluid. Galacturonan, which was partially substituted with methyl and 0-acetyl ester groups, and rhamnogalacturonan were the main constituents of the linear regions of the sugar chains of PD. The ramified region contained mainly 1,4-linked B-o-galactopyranose residues and, to a lesser extent, 1,5-linked a-L-arabinofuranose residues. The separation of PD, by DEAE-cellulose column chromatography, yielded two pectic fractions: PD-1 and PD-2, eluted with 0.1 and 0.2 M NaC1, respectively. Enzymatic digestion of PD with 1,4-a-o-polygalacturonase yielded the fraction PD-E. The parent pectin PD and the PD-1 fraction were found to diminish the adhesion of peritoneal leukocytes at the concentrations of 0.05-1.0 mg/ml. However, the PD-E fraction failed to have an effect on cell adheMon at the concentrations of 0.05-0.1 mg/ml. PD, PD-1 and PD-E were found to inhibit the production of superoxide anion radicals by reducing xanthine oxidase activity by 38%, 97% and 47%, respectively. Therefore, the PD-1 fraction appeared to be an active fragment of pectic macromolecule isolated from fresh plum with a simulated gastric fluid. (C) 2013 Elsevier Ltd. All rights reserved.