Ultrasound-assisted aqueous two-phase extraction of total flavonoids from and antioxidant activity of extracted flavonoids.

Here, the extraction of total flavonoids from (TF) by aqueous two-phase extraction combined with ultrasound is presented. The extraction was optimized via a single-variable approach using the variables of mass fraction of ethanol and NaHPO, ultrasonication time, and TF sample amount. Response surface methodology (RSM) was then applied to determine the best conditions for extraction using the following three key parameters: ultrasonication time, ethanol mass fraction, and NaHPO mass fraction.