Novel solvents combined with two-step extraction of total flavonoids from Pueraria lobata: In-depth optimization, mechanistic investigation and antioxidant activities

A green and efficient extraction technique was innovatively developed in this study, utilizing ternary deep eutectic solvent combined with in-situ ultrasonic synergistic extraction to extract total flavonoids from Pueraria lobata , aiming to address the drawbacks of traditional extraction methods. After systematic screening of 20 eutectic solvent systems, choline bitartrate: Lactic acid: Glycerol was recognized as the optimal solvent. A set of optimal parameters was acquired through the integrated response surface methodology-artificial neural network-genetic algorithm framework, which comprised the following conditions: 37% water content, 11 min vortex time, a liquid/solid ratio of 66:1 mL/g, 30 min ultrasonic duration, and 240 W ultrasonic power. The optimized extraction efficiency was 223.79 ± 1.89 mg/g. chemical composition identification of P.lobata through ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry resulted in the clear identification of 15 compounds, including 14 flavonoids. Structural evidence for the successful preparation of the novel ternary deep eutectic solvent was provided by FT-IR spectroscopic analysis, while the underlying extraction mechanism was elucidated through scanning electron microscopy and molecular dynamics simulations. Furthermore, the TF extract demonstrated considerable antioxidant capacity across three independent assays, indicating its promising potential for development into functional health products. To summarize, a novel extraction method was developed in this study, which could be employed for extracting bioactive flavonoids from P. lobata . This work offered a theoretical foundation for advancing green chemistry and further developing traditional Chinese medicines with food-medicine dual properties