Objective: Various biological activities have been reported for Daphne gnidium, the aim of the present study was to determine polyphenols and some biological activities of extracts from the shoots of this plants.Methods: Phenolic and flavonoids contents of D. gnidium extracts (DGE) were determined by Folin-Ciocalteau and identified by HPLC–DAD/MS. Free radical scavenging and antioxidant potential of the crude (CE), chloroform (CHE) and ethyl acetate (EAE) extracts of D. gnidium shoots were investigated using several in vitro and ex vivo assays, including 2, 2-diphenyl-picrylhydrazyl radical scavenging, superoxide anion scavenging (by both enzymatic and nonenzymatic methods) and hydroxyl radical scavenging capacity methods. The antioxidant activity of the extracts was measured using the xanthine oxidase (XO) inhibitory activity, reducing power and ß-carotene-linoleic bleaching assays. Inhibition of lipid peroxidation and oxidative hemolysis were also performed to confirm the protective effect of these extracts.Results: It was found that values of phenolics varied between 130.84±5.99 and 137±7.66 mg gallic acid equivalent/g dry extract. HPLC analysis revealed the presence of cinnamic acid derivatives and other metabolites from the flavonoids family. All extracts exhibited a superoxide scavenging capacity. The EAE had the highest antioxidant activity as measured by DPPH radical and hydroxyl radical scavenging activity. The extracts showed an inhibitory effect on xanthine oxidase, the IC50 rangesfrom 0.021±0.001 to 0.061±0.001 mg/ml. The EAE showed also potent reducing power ability. CHE possess an inhibition ratio of (92.11%) in the linoleic acid oxidation assay close to that of BHT (96.77%). All extracts exhibited antioxidant activity in the linoleic acid emulsion system (3.87-61.11 %). Under the oxidative action of AAPH, EAE and CE showed higher protective effect against erythrocytes hemolysis than the CHE. The percentage of hemolysis (H%) determined for EAE and CE after 1 h of incubation were 0% and 1.9%, respectively.Conclusion: This study indicates that DGE contains relevant antioxidant compounds responsible, at least in part, for its antioxidant and radicals scavenging activity. Flavone derivatives were determined as the main active component of the shoots part and the CHE was the most active extract.Â
