Abstract:In this study, antioxidant activity of a jujube polysaccharide from Zizyphus jujuba Mill was investigated by establishing 4 kinds of in vitro models, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical (?OH) scavenging activities as well as reducing power assay. The model of macrophage RAW264.7 induced by lipopolysaccharide (LPS) was established to study the anti-inflammatory activity of jujube polysaccharide. The results showed that jujube polysaccharide had strong antioxidant activity and the IC50 of jujube polysaccharide on the DPPH?, ABTS and ?OH free radicals were 0.9, 2.8 and 1.1 mg/mL, respectively. The antioxidant activity of jujube polysaccharide exhibited a dose-dependent manner. When the value of total reducing power reached 1.0, the corresponding Vc and jujube polysaccharide concentrations were 0.08 mg/mL and 2.95 mg/mL, respectively. High doses of jujube polysaccharide could significantly reduce the levels of inflammatory cytokines including cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) in RAW264.7 cells, which showed that jujube polysaccharide had strong anti-inflammatory activity. Jujube polysaccharide was expected as an antioxidant and anti-inflammatory agents used in functional food and medicine industry.