Ultrasound-Assisted Deep Eutectic Solvent Extraction of Flavonoids from Cercis chinensis Seeds: Optimization, Kinetics and Antioxidant Activity

作者：Penghua Shu, Shuxian Fan, Simin Liu, Meng Yu, Na Wang, Shoujie Guo, Hao Yin, Di Hu, Xin Fan, Si Chen, Jingjing He, Tingting Guo, Wenhao Zou, Lin Zhang, Xialan Wei, Jihong Huang · 发表于：Separations · 年份：2025 · DOI：10.3390/separations12100269 · 被引用次数：5 · 研究领域：Analytical Chemistry and Chromatography、Synthesis of Organic Compounds、Natural Compound Pharmacology Studies

This study establishes an efficient and eco-friendly ultrasound-assisted extraction (UAE) method for total flavonoids present in Cercis chinensis seeds using natural deep eutectic solvents (NADES). Among nine NADES formulations screened, choline chloride–levulinic acid (ChCl–Lev, 1:2) demonstrated optimal performance, yielding 112.1 mg/g total flavonoids. Through Response Surface Methodology (RSM), the ultrasound-assisted extraction (UAE) parameters were explored. Under the optimized conditions (water content of 30%, time of 28 min, temperature of 60 °C, and solvent-to-solid ratio of 1:25 g/mL), the total flavonoid yield reached 128.5 mg/g, representing a 195% improvement compared to conventional ethanol extraction. The recyclability of NADES was successfully achieved via AB-8 macroporous resin, retaining 80.89% efficiency after three cycles. Extraction kinetics, modeled using Fick’s second law, confirmed that the rate constant (k) increased with temperature, highlighting temperature-dependent diffusivity as a key driver of efficiency. The extracted flavonoids exhibited potent antioxidant activity, with IC50 values of 0.86 mg/mL (ABTS•+) and 0.69 mg/mL (PTIO•). This work presents a sustainable NADES-UAE platform for flavonoid recovery and offers comprehensive mechanistic and practical insights for green extraction of plant bioactives.