Antioxidant activity of Inonotus obliquus polysaccharide and its amelioration for chronic pancreatitis in mice

Inonotus obliquus polysaccharide (IOP) was extracted by water with a yield of 9.83% and purified by an anion-exchange DEAE cellulose column and Sephadex G-200 gel with a polysaccharide content of 98.6%. The scavenging activities for 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and hydroxyl radicals of IOP were 82.3% and 81.3% respectively at a concentration of 5 mg/mL. IOP was composed of Man, Rha, Glu, Gal, Xyl and Ara in a molar ratio of 9.81:3.6：29.1：20.5：21.6：5.4 respectively. The gel permeation chromatography indicated that IOP was a homogeneous polysaccharide with molecular weight of 32.5 kDa. IOP helped to alleviate pancreatic acinar atrophy and weight loss for chronic pancreatitis (CP) mice induced by Diethyldithiocarbamate (DDC). The SOD level was increased most by IOP-H treatment (400 mg/kg body weight). MDA, IL-1β and LDH were significantly decreased by IOP treatment, especially hydroxyproline, IFN-γ and AMS levels were decreased 39.18%, 37.82% and 41.57% by IOP-H treatment respectively compared to MC group. In conclusion, IOP possessed strong antioxidant activity for scavenging free radicals in vitro and vivo which could be propitious to CP therapy in mice.