Extraction and antioxidant activity of total flavonoids from chamomile.

By optimizing the extraction and purification process, the study first used supercritical CO2 to remove the lipophilic components of chamomile, and then combined with ultrasound assisted the extraction of total flavonoids from chamomile. The total flavonoids in chamomile were separated and purified using macroporous resin, and the total flavonoid components were analyzed and characterized. The optimal process conditions for obtaining supercritical CO2 to remove fat soluble components from chamomile are: extraction temperature of 50, extraction time of 60 minutes, extraction pressure of 25 MPa, and chamomile fat removal rate of 8.66%. The optimal process conditions for ultrasound assisted extraction of total flavonoids from chamomile are: ultrasound time of 15 minutes, ethanol volume fraction of 50%, solid-liquid ratio of 125 gmL, ultrasound power of 200 W, and total flavonoid extraction rate of 4.25%. After purification, the purity of total flavonoids in chamomile increase from 6.04% to 52.25%, while the purity of total flavonoids in chamomile is only 25.47% using the same purification process using a single ultrasound assisted extraction method without supercritical CO2 extraction. The results show that the combination of supercritical CO2 extraction and ultrasound assisted extraction can more efficiently extract total flavonoids from chamomile, and reduce the odor. The purified total flavonoids from chamomile can effectively scavenge DPPH and ABTS free radicals, and have strong antioxidant activity. [ABSTRACT FROM AUTHOR]