Composition, antioxidant activities and hepatoprotective effects of the water extract of Ziziphus jujuba cv. Jinsixiaozao

Abstract

In this study, we aimed to evaluate the composition, antioxidant activities, and hepatoprotective effects of water extracts of Ziziphus jujuba cv. Jinsixiaozao. In the water extract, the contents of total phenolics, total flavonoids and polysaccharides were 1.43 mg of gallic acid equivalent (GAE) per g of dry plant, 0.17 mg of rutin equivalent (RE) per g of dry plant, and 3.80 mg per g of dry plant, respectively. The main components of the phenolic acids were protocatechuic acid, catechol, p-hydroxybenzoic acid, vanilla acid and p-coumaric acid (17.02, 5.87, 7.46, 2.95, 1.06 μg per g of dry plant, respectively). The results show that the water extract of jujube (WEJ) had a significant antioxidant effect which was evaluated by DPPH, ABTS, ORAC and FRAP assays. In addition, they dramatically (p < 0.01) decreased the liver index, the activities of serum hepatic AST, ALT and LDH, levels of total cholesterol (TC) and triglyceride (TG) which were induced by alcohol. The administration of mice with the WEJ significantly (p < 0.01) reduced MDA and enhanced the activities of antioxidant enzymes SOD and GSH-PX compared to the model group. WEJ pre-intake decreased subsequent alcohol-induced IL-6 and TNF-α; and reduced the nuclear factor kappa (NF-κB p65) and total nitric oxide synthase (iNOS) activities in the liver (p < 0.01). Furthermore, the pathological analyses of liver proved the preventive and therapeutic effects of the WEJ in mice. Therefore, the water extract of jujube with antioxidant activities could be used to prevent and treat liver damage and inflammation induced by alcohol.