Abstract:Objective To investigate the effect of deep eutectic solvent (DES) on the extraction rate of total flavonoids from Zanthoxylum bungeanum Maxim. leaves and analyze their antioxidant activity.Methods Using Z. bungeanum leaves as raw material and total flavonoid extraction rate as the evaluation index, this study performs ultrasound-assisted extraction to screen the optimal DES system. The scavenging capacities of the extracted total flavonoids against hydroxyl radicals (·OH) and DPPH radicals are determined.Results The highest extraction rate of total flavonoids is achieved using a choline chloride-ethylene glycol DES system (ncholine chloride∶nethylene glycol=1∶3) with 22% water content, a solid-to-liquid ratio (mZ. bungeanum powder∶Vsolvent) of 1∶47 (g/mL), and ultrasonic time of 15 min. The total flavonoids from Z. bungeanum leaves exhibit a maximum hydroxyl radical scavenging rate of (63.89±0.26)% and a DPPH radical scavenging rate as high as (89.01±0.51)%.Conclusion DES demonstrates excellent efficiency in extracting total flavonoids from Z. bungeanum leaves, and the extracted total flavonoids possess strong antioxidant activity.