Optimization of Extraction Process for Flavonoids from Artemisia anethifolia Web. ex Stechm by Response Surface Methodology and Evaluation of Their Antioxidant Activity

Response surface methodology was employed to optimize the extraction of flavonoids from young stems and leaves of Artemisia anethifolia Web.ex Stechm.Meanwhile,the antioxidant activity in vitro was evaluated by hydroxyl radical scavenging assay,superoxide anion radical scavenging assay,total reducing power assay,and anti-lipid peroxidation assay with vitamin C as the reference.The results indicated that the optimal extraction conditions were extraction temperature of 80 ℃,extraction time of 1.75 h,material-to-liquid ratio of 1:27.5,and repeated extraction number of 2.Under these extraction conditions,the predicted and actual values of flavonoids yield were 3.002% and 2.996%,respectively.Artemisia anethifolia Web.ex Stechm flavonoids revealed a relatively weaker scavenging effect on superoxide anion radicals when compared with vitamin C,but revealed better scavenging effect on hydroxyl free radicals,stronger inhibitory activity on lipid peroxidation and higher reducing power.Therefore,Artemisia anethifolia flavonoids are effective natural antioxidants.