School of Pharmacy, Zunyi Medical University, Zunyi 563003, China.
Molecules. 2018 Dec 11;23(12):3284. doi: 10.3390/molecules23123284.
As a new and green solvent, ionic liquids (ILs) have received more attention during the green extraction and separation process for natural medicines. In this paper, IL-ultrasound-assisted extraction (IL-UAE) of total biflavonoids (TBFs) from was firstly developed, and different ILs were employed and compared. Based on single-factor experiment, solid⁻liquid ratio (1:10⁻1:14 g/mL), IL concentration (0.6⁻1.0 mmol/mL), and extract temperature (40⁻60 °C) were further explored, according to response surface methodology (RSM), with TBF yields as the index. Moreover, antioxidant activity of TBF extract was analyzed by four methods, i.e., 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzth-iazoline-6-sulphonate (ABTS) free radical scavenging assay, ferric ion reducing power assay, and chelation of ferrous ions assay. The results indicated that [C₆mim]PF₆ had a high selectivity and efficiency. Moreover, important parameters for the extraction process were investigated and optimized. Through parameter optimization (0.8 mmol/L, 250 W, 40 min, 1:12.7 g/mL, and 47 °C), a yield of 18.69 mg/g biflavonoids was obtained from the extract of . Compared with ethanol-UAE, heat-reflux extraction, Soxhlet extraction, and percolation extraction, IL-UAE could not only obtain higher yield in a shorter time, but also reduce the solvent consumption. In addition, TBF extract showed potential antioxidant activity based on the above four antioxidant methods. In short, IL-UAE was first employed to develop a novel and green extraction method for TBF content, and this experiment provides valuable references for further utilization of .
作为一种新型绿色溶剂，离子液体（ILs）在天然药物的绿色提取和分离过程中受到了更多的关注。本文首次开发了离子液体-超声辅助提取（IL-UAE）法从 中提取总二氢黄酮（TBFs），并比较了不同的 IL。基于单因素实验，进一步根据响应面法（RSM），以 TBF 得率为指标，探讨了固液比（1:10-1:14 g/mL）、IL 浓度（0.6-1.0 mmol/mL）和提取温度（40-60°C）。此外，还通过 2,2-二（4-叔辛基苯基）-1-吡咯基二氢吡唑（DPPH）和 2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）自由基清除试验、铁离子还原能力试验和亚铁离子螯合试验分析了 TBF 提取物的抗氧化活性。结果表明，[C6mim]PF6 具有较高的选择性和效率。此外，还研究和优化了提取过程的重要参数。通过参数优化（0.8 mmol/L、250 W、40 min、1:12.7 g/mL 和 47°C），从 提取物中获得了 18.69 mg/g 二氢黄酮的产率。与乙醇-UAE、热回流提取、索氏提取和渗滤提取相比，IL-UAE 不仅可以在更短的时间内获得更高的产率，而且可以减少溶剂消耗。此外，TBF 提取物在上述四种抗氧化方法中表现出潜在的抗氧化活性。总之，首次采用 IL-UAE 开发了一种新的绿色 TBF 含量提取方法，该实验为进一步利用 提供了有价值的参考。
