Box-Behnken design for extraction optimization, characterization and in vitro antioxidant activity of Cicer arietinum L. hull polysaccharides

The optimal extraction conditions with a yield of 5.37 +/- 0.15% for extraction of polysaccharides from chickpea (Cicer arietinum L.) hull (CHPS) were determined as extraction temperature 99 degrees C, extraction time 2.8 h and ratio of water to raw material 24 mL/g. Three fractions of CHPS-1, CHPS-2 and CHPS-3, with average molecular weight of 3.1 x 10(6), 1.5 x 10(6) and 7.8 x 10(5) Da, respectively, were obtained from crude CHPS by chromatography of DEAE Fast Flow and Sephadex G-100. CHPS-1 was composed of man nose, rhamnose, galactose, galacturonic acid, glucose and arabinose, CHPS-2 was composed of mannose, rhamnose, galacturonic acid, galactose, xylose and arabinose, CHPS-3 was composed of galacturonic acid, galactose and rhamnose. CHPS-3 showed the strongest reducing power and protective effect on H2O2-induced oxidative injury in PC12 cells and highest scavenging activities against DPPH and ABTS radicals, while CHPS-2 showed the highest scavenging activity against superoxide anion radical. (C) 2016 Elsevier Ltd. All rights reserved.