Evaluation of physicochemical characteristics and antioxidant property of Prunus avium gum exudates.

In this study some physicochemical properties and elemental analysis of Prunus avium gum exudates were investigated. The gum studied had, on average, 75.14% carbohydrate, 11.3% uronic acids, 1.11% protein, 7.53% moisture content (w.b.) and 3.12% ash. Measured values for the angle of repose, Carr's index and Hausner ratio showed the good flow ability for the gum powder. The viscosity of 1% aqueous solution of the gum exhibited a Newtonian type of flow and with pH reduction the swelling index was increased. The average molecular weight of the main polysaccharide fraction was about 1.46×105Da (146kDa). GC analysis showed that the main polysaccharide was composed of four kinds of neutral monosaccharides, namely mannose (Man), arabinose (Ara), galactose (Gal) and xylose (Xyl) with a relative molar ratio of 1.0:14.7:7.1:2.4. FTIR analysis showed the presence of carboxyl and hydroxyl groups and glycosidic linkage. The antioxidant activity of the gum was evaluated by determining DPPH scavenging and total phenolic contents which showed poor antioxidant property.