Choline leucine ionic liquid solution was chosen to simultaneously extract flavonoids and pectin from ponkan peels, which were subsequently isolated by the corresponding K₃PO₄-based aqueous biphasic systems (ABS). Under optimized conditions of 54% solution for 100 min extraction at liquid–solid ratio 17, the predicted yields of flavonoids and pectin achieved 1.33% and 13.42%, respectively, the flavonoids determined directly after extraction and the pectin after ABS purification, with the two corresponding measured yields of 1.26% ± 0.04% and 12.85% ± 0.51%. Under optimal extraction, crude flavonoids contained maximal total flavonoid content of about 20% ± 1% after purification of the ABS involving 25% K₃PO₄ and dilution precipitation. What was directly isolated from K₃PO₄-rich phase was presumed to be a modified pectin.

In this work, a two-step extraction methodology of ionic liquid-based ultrasonic-assisted extraction (IL-UAE) and ionic liquid-based aqueous two-phase system (IL-ATPS) was developed for the extraction and purification of secoisolariciresinol diglucoside (SDG) from flaxseed. In the IL-UAE step, several kinds of ILs were investigated as the extractants, to identify the IL that affords the optimum extraction yield. The extraction conditions such as IL concentration, ultrasonic irradiation time, and liquid–solid ratio were optimized using response surface methodology (RSM). In the IL-ATPS step, ATPS formed by adding kosmotropic salts to the IL extract was used for further separation and purification of SDG. The most influential parameters (type and concentration of salt, temperature, and pH) were investigated to obtain the optimum extraction efficiency. The maximum extraction efficiency was 93.35% under the optimal conditions of 45.86% (w/w) IL and 8.27% (w/w) Na₂SO₄ at 22 °C and pH 11.0. Thus, the combination of IL-UAE and IL-ATPS makes up a simple and effective methodology for the extraction and purification of SDG. This process is also expected to be highly useful for the extraction and purification of bioactive compounds from other important medicinal plants.

(1) Background: The environmentally friendly choline-amino acid ionic liquids (ChAAILs) and deep eutectic solvents (DESs) have been used as excellent alternatives to volatile organic compounds (VOCs) and ionic liquids (ILs) in recent years; (2) Methods: Thus, ChAAILs/salt and DESs/salt aqueous two-phase systems (ATPSs) were developed for the chiral extraction of phenylalanine enantiomers. The optimum ATPS of [Ch][L-Pro]/K₃PO₄ was chosen, and the influencing parameters were investigated, including ChAAILs concentration, salt concentration, chiral selector concentration, extraction temperature, phenylalanine concentration, and system pH; (3) Results: The phenylalanine enantiomers were mainly extracted into the top phase (ChAAIL-rich phase), meanwhile, the (S)-phenylalanine [(S)-Phe)] was preferentially recognized by the chiral selector in the top phase. The maximum separation factor (α) of 2.05 was obtained under the optimal conditions; and (4) Conclusions: This ATPS that was used for the chiral extraction of enantiomers is much more environmentally friendly, simple, and rapid, and has the potential to be used in the enantioselective extraction of other enantiomers.

(1) Background: Ionic liquids (ILs) are considered “green” solvents and have been widely used in the extraction and separation field in recent years; (2) Methods: In this study, some common ILs and functionalized magnetic ionic liquids (MILs) were used as adjuvants for the solvent extraction of paclitaxel from Taxus x media (T. x media) using methanol solution. The extraction conditions of methanol concentration, IL type and amount, solid–liquid ratio, extraction temperature, and ultrasonic irradiation time were investigated in single factor experiments. Then, three factors of IL amount, solid–liquid ratio, and ultrasonic irradiation time were optimized by response surface methodology (RSM); (3) Results: The MIL [C₄MIM]FeCl₃Br was screened as the optimal adjuvant. Under the optimization conditions of 1.2% IL amount, 1:10.5 solid–liquid ratio, and 30 min ultrasonic irradiation time, the extraction yield reached 0.224 mg/g; and (4) Conclusions: Compared with the conventional solvent extraction, this ultrasonic assisted extraction (UAE) using methanol and MIL as adjuvants can significantly improve the extraction yield, reduce the use of methanol, and shorten the extraction time, which has the potentiality of being used in the extraction of some other important bioactive compounds from natural plant resources.

The magnetic aqueous micellar two-phase system (MAMTPS) has the advantages combined of magnetic solid phase extraction (MSPE) and aqueous micellar two-phase system (AMTPS). Thus, MAMTPS based on Fe₃O₄ magnetic nanoparticles (MNPs) and a nonionic surfactant Triton X-114 (TX-114) was developed for the extraction, enrichment and removal of three dyes (Congo red, methyl blue, and methyl violet) from aqueous solutions in this study. The MNPs Fe₃O₄@NH₂ was screened as the optimal MNPs benefiting the extraction. Then, the influencing factors of MNPs amount, TX-114 concentration, vibration time, and extraction temperature were investigated in detail. The results showed that the extraction efficiencies of three dyes almost reached 100% using MAMTPS under the optimal conditions; MAMTPS had higher extraction ability than the individual MSPE or AMTPS. Thus, MAMTPS had the advantages of simple operation, high extraction ability, easy recycling of MNPs, and short phase-separation time, which showspotential for use in the extraction and analysis of contaminants from water samples.