Optimization of Extraction Process of Total Flavonoids from Dracocephalum Moldavica L. of Inner Mongolia and Analysis of Its Antioxidant Components

OBJECTIVE To optimize the extraction process of total flavonoids components from Inner Mongolia Dracocephalum moldavica L., and to analyze its antioxidant active ingredients. METHODS Single factor test combined with response surface method was used to optimize the extraction process. DPPH free radical scavenging experiment, ABTS free radical scavenging experiment, hydroxyl free radical inhibition experiment and superoxide anion free radical inhibition experiment were used to screen the antioxidant active components of the extract. The antioxidation active parts were analyzed by high performance liquid chromatography-electrospray ion source-ion trap-time of flight mass spectrometry(LC-MS-IT-TOF). RESULTS The optimum preparation conditions were as follows:extraction temperature of 67℃, volume percentage of ethanol 63%, solid-liquid ratio of 1:58, total flavonoid content of 4.77% in the extract. The antioxidant activity of the total flavonoids in Dracocephalum moldavica L. was ethyl acetate, which mainly contained rosmarinic acid, methyl rosmarinate, luteolin, apigenin, apigenin-7-O-β-D-glucoside and other chemical components. CONCLUSION The preparation method of total flavonoids of Inner Mongolia Dracocephalum moldavica L. is established for the first time. The method is simple and easy to operate, and rich in flavonoids. The ethyl acetate extract in total flavonoids in Dracocephalum moldavica L. is the main antioxidant components, containing a variety of flavonoids.