Abstract:

      We addressed the impact of extraction conditions on the extraction amount of total flavonoids with L9(34) orthogonal test. We also evaluated its antioxidative activity by Fenton system and pyrogallol autooxidation method. We further analyzed the correlation between total flavonoids and antioxidative activity with multiple linear regression. Results show that the optimal extraction conditions are 75% ethanol (solid and liquid ratio of 1:20),4 times extraction and extraction time of 30 min. Its optimal extraction rate is 3.423%. Obvious doseeffect relationship is shown between concentration and its clearance capability to ·OH and O₂·. Positive correlation is also exhibited between antioxidative activity and total flavonoids amount. Total flavonoids from Herba Gueldenstaedtiae  have stronger antioxidative activity and are effective natural antioxidants.

Key words: Herba Gueldenstaedtiae, total flavonoids, antioxidative activity, correlation