High Efficient Extraction of Coumarins From <i>Viola philippica</i> by Ultra‐high Pressure‐assisted Micellar Extraction

ABSTRACT To address the issues of low efficiency and high solvent consumption associated with traditional extraction methods, Viola philippica was used as the raw material for the extraction of coumarin compounds by ultra‐high pressure‐assisted micellar extraction (UHPAME). The optimal extraction process was investigated using response surface methodology (RSM), and the antioxidant activity of the extracted coumarin was evaluated in vitro. Single‐factor experiments were conducted to analyze the effects of extraction times, extraction pressure, and holding time on the yield. Based on these results, a Box–Behnken design (BBD) was applied to establish a response surface regression model. The optimized conditions were determined as follows: extraction pressure of 148.297 MPa, holding time of 6.760 min, and 3.054 extraction times, resulting in an average esculetin yield of 3.732 mg/g. In vitro antioxidant assays demonstrated that esculetin exhibited significant antioxidant activity, with IC 50 values of 23.91 µg/mL against DPPH radicals and 3.45 µg/mL against ABTS radicals. This study indicates that UHPAME is an efficient and environmentally friendly method for extracting coumarins from Viola philippica , providing a valuable reference for further research.