Herein, an eco-friendly deep eutectic solvents-based ultrasonic-assisted extraction (DES-based UAE) procedure was exploited for high efficient extraction of natural antioxidants from Polygonum aviculare leaves (PALs). Choline chloride-levulinic acid (ChCl-Lev) was adopted for the first time as extractants for further optimization. Based on the results of single-factor experiments, the optimal extraction conditions for simultaneously maximizing the TPC, TFC and antioxidant activities were obtained by response surface methodology (RSM). RSM results indicated that four independent variables had evident effects on all responses, while ultrasonic temperature and liquid to solid ratio (L/S) showed significant interaction effects on the TFC and FRAP. Under the optimal conditions (L/S of 85:1, ultrasonic time of 60 min, ultrasonic temperature of 70 °C and water content in DES of 38%), the corresponding responses resulted in: TPC-102.07 ± 2.51 mg GAE/g DW, TFC-69.43 ± 9.37 mg RE/g DW, DPPH^•-315.26 ± 7.52 μmol TE/g DW, and FRAP-496.79 ± 6.38 mM Fe(Ⅱ)SE/g DW. The measured results were consistent with the predicted values. Moreover, a comparative study showed that the ChCl-Lev-based UAE resulted in higher TPC, TFC and antioxidant activities than other available extraction methods. HPLC-DAD analysis results showed that ChCl-Lev-based UAE yielded high levels of antioxidants including gallic acid (39.80 mg/g DW), 5-caffeoylquinic acid (11.83 mg/g DW), myricitrin (10.47 mg/g DW), 3′′-O-galloylmyricitrin (7.91 mg/g DW), 3-chlorogenic acid (7.16 mg/g DW), quercitrin (4.26 mg/g DW), and avicularin (3.02 mg/g DW). This study develops an eco-friendly and high-efficient ChCl-Lev-based UAE method to obtain extracts rich in natural antioxidants from medicinal plants, which can be well applied in food, cosmetic and pharmaceutical industries.

在本文中，利用生态友好的基于低共熔溶剂的超声辅助萃取（基于DES的阿联酋）程序，可以高效地从何首乌中提取天然抗氧化剂。离开（PAL）。胆碱氯化物-乙酰丙酸（ChCl-Lev）首次被用作提取剂，用于进一步优化。基于单因素实验的结果，通过响应面法（RSM）获得了同时最大化TPC，TFC和抗氧化剂活性的最佳提取条件。RSM结果表明，四个独立变量对所有响应都有明显影响，而超声温度和液固比（L / S）对TFC和FRAP表现出显着的相互作用。在最佳条件下（L / S为85：1，超声时间为60分钟，超声温度为70°C，DES中的水分含量为38％），相应的响应为：TPC-102.07±2.51 mg GAE / g DW，TFC-69.43±9.37 mg RE / g DW，DPPH ^•-315.26±7.52μmolTE / g DW和FRAP-496.79±6.38 mM Fe（Ⅱ）SE / g DW。测量结果与预测值一致。此外，一项比较研究表明，与其他可用的提取方法相比，基于ChCl-Lev的阿联酋具有更高的TPC，TFC和抗氧化活性。HPLC-DAD分析结果表明，基于ChCl-Lev的阿联酋产生了高水平的抗氧化剂，包括没食子酸（39.80 mg / g DW），5-咖啡酰奎尼酸（11.83 mg / g DW），杨梅素（10.47 mg / g DW）， 3′′- O-galloylmyricitrin（7.91 mg / g DW），3-绿原酸（7.16 mg / g DW），槲皮苷（4.26 mg / g DW）和avicularin（3.02 mg / g DW）。这项研究开发了一种环保，高效的基于ChCl-Lev的阿联酋方法，可以从药用植物中提取富含天然抗氧化剂的提取物，可以很好地应用于食品，化妆品和制药行业。