Optimization of the extraction process of flavonoids from Trollius ledebouri with natural deep eutectic solvents

Abstract

In recent years, natural deep eutectic solvents have been favored greatly due to their environment friendly, mild biological toxicity and simple biodegradability. Natural deep eutectic solvents gradually applied for the extracting bioactive compounds from natural products efficiently. In this study, 20 natural deep eutectic solvents were prepared and their physical and chemical properties were tested. The ultrasonic-assisted extraction method was used to extract flavonoids from Trollius ledebouri and high-performance liquid chromatography-ultraviolet was applied to examine two main bioactive flavonoids (orientin and vitexin). Compared with traditional solvents (water and 60% ethanol solution), natural deep eutectic solvents composed of L(-)-proline and levulinic acid (molar ratio 1:2) show a super extraction efficiency. On this basis, the response surface method was used to optimize the extraction temperature, extraction time, water contents, and solid-liquid ratio. As a consequence, the extraction temperature 60°C, extraction time 18 min, water content 14% (v/v), and the solid-liquid ratio 48 mL⋅g −1 were chosen as the best extraction process. This study shows that natural deep eutectic solvents can effectively extract flavonoids from T. ledebouri, laying a foundation for the further application of natural deep eutectic solvents to extract bioactive compounds from natural products.

Microwave‐assisted deep eutectic solvent extraction of five lignans from Schisandra chinensis

“…However, further increasing the extraction temperature (>70 • C) does not improve the extraction efficiency. In addition, the reaction system generates too much heat energy at high extraction temperatures, which may lead to the degradation of unstable substances and thus reduce the extraction yield [32]. Therefore, the extraction temperature was set at 70 • C in the following experiments.…”

Single-Stage Extraction and Separation of Co2+ from Ni2+ Using Ionic Liquid of [C4H9NH3][Cyanex 272]

“…The β Co/Ni increases with the growth of T e . The reason is that higher temperature reduces the viscosity and surface tension of the extraction system, which is beneficial to mass transfer [ 37 ]. In addition to this, the extraction reaction of Co 2+ using extractant of [C 4 H 9 NH 3 ][Cyanex 272] is an endothermic reaction, and the higher T e is conductive to the reaction [ 10 ].…”

“…According to the single-factor experimental results, three independent factors, i.e., pH ini (A), t e (B), and T e (C), were found to be responsible for the β Co/Ni . With the aim of analyzing the A, B, and C, three-factor and three-level Box–Behnken experimental design was used to conduct response surface analysis [ 37 ], and the three factors were optimized at three levels (−1, 0, −1) ( Table 1 ).…”

Advances of responsive deep eutectic solvents and application in extraction and separation of bioactive compounds

“…In the following years, Choi et al introduced natural DES(NADES)consisting of natural product components for these mixtures in 2011, which has led to the development of DESs as a greener solvent [20,21]. It has been shown that the DESs chosen as extraction solvents are not only green but that DESs can also improve the extraction efficiency of bioactive compounds [22][23][24]. Therefore, DESs have gradually gained attention as a new type of green solvent [25,26].…”