Abstract:The polysaccharides extracted by water-extract and ethanol-precipitation from Ginkgo nuts were purified by Sevag method for protein removing and macroporous adsorption resin for the de-colorization. The composition of the polysaccharide was analyzed by Ultraviolet spectrum (UV), high-performance liquid chromatography (HPLC), and infrared spectra (IR). The in vitro antioxidant activities of the polysaccharide were determined by DPPH, superoxide radicals and hydroxyl radicals scavenging assays. The effect of the polysaccharide on the content of SOD, GSH-PX, MAD and CAT in the serum and liver of the hyperlipemia mice were measured to determine the antioxidant activity in vivo. It was found that the ginkgo polysaccharide consisted of 3 kinds of monosaccharide, including glucose, galactose and xylose, with the molar ratio of 2.26:19.60:4.29, in the form of pyranose containing α-glycosidic bond. The Ginkgo polysaccharide showed the significant DPPH, superoxide radicals and hydroxyl radicals scavenging activities, with IC50 values being of 0.15 mg/L, 0.30 mg/L and 0.47 mg/mL, respectively. The antioxidant in vivo showed that the ginkgo polysaccharide could evidently increase the concentrations of SOD, GSH-Px and CAT, and decrease the concentration of MDA in serum and liver.
