Isolation, Purification and Antioxidant Activity of Inonotus obliquus Polysaccharide

The chemical compositions of Inonotus obliquus were analyzed and crude polysaccharides (IOP)were isolated from Inonotus obliquus by water extraction. The component of polysaccharides were purified by DEAE-52, and Sephadex G-100 column chromatography, and the highly active polysaccharide component was screened out through antioxidant activity, and the purity of the polysaccharide component was analyzed by high-performance liquid chromatography.The experimental results showed that the chemical composition of Inonotus obliquus was rich, including polysaccharide 13.10%± 0.31%, reducing sugar 4.21%±0.40%, protein 2.70%±0.71%, ash 9.60%±0.31%.After IOP undergoes DEAE-52 cellulose column chromatography, four monosaccharide components were obtained: IOP-1, IOP-2, IOP-3, and IOP-4. Antioxidation experiments on four polysaccharide components found that IOP-2 had the highest scavenging rate for DPPH free radicals. After passing through Sephadex-100 chromatography column, IOP-2 obtained two polysaccharide components: IOP-2a and IOP-2b. Compared with its antioxidant activity, the polysaccharide component with higher activity was selected as IOP-2a. Using high performance liquid chromatography to identify the polysaccharide component IOP-2a, only one symmetrical peak was detected, indicating that IOP-2a was a homogeneous polysaccharide.