Enhanced Extraction Efficiency of Flavonoids from Pyrus ussuriensis Leaves with Deep Eutectic Solvents

Abstract

In this study, deep eutectic solvents (DESs) were synthesized using different ratios of choline chloride (CC) and dicarboxylic acids, and their eutectic temperatures were determined. The DES synthesized using CC and glutaric acid (GA), which showed a higher extraction efficiency than conventional solvents, was used for the extraction of flavonoid components from Pyrus ussuriensis leaves (PUL), and the extraction efficiency was evaluated using the response surface methodology. The flavonoid components rutin, hyperoside, and isoquercitrin were identified through high-performance liquid chromatography (HPLC), equipped with a Waters 2996 PDA detector, and HPLC mass spectrometry (LC-MS/MS) analyses. The optimum extraction was achieved at a temperature of 30 °C using DES in a concentration of 30.85 wt.% at a stirring speed of 1113 rpm and an extraction time of 1 h. The corresponding flavonoid content was 217.56 μg/mL. The results were verified by performing three reproducibility experiments, and a high significance, with a confidence range of 95%, was achieved. In addition, the PUL extracts exhibited appreciable antioxidant activity. The results showed that the extraction process using the DES based on CC and GA in a 1:1 molar ratio could effectively improve the yield of flavonoids from PUL.

Anti-Inflammatory Activity of Vacuum Distillate from Panax ginseng Root on LPS-Induced RAW264.7 Cells

“…Ginseng extracts prepared by various methods are reported to exhibit anti-inflammation activity by their suppression of both iNOS and COX-2 expressions [29]. This effect comes mostly from ginsenosides, the main ingredient in ginseng [7]. The antiinflammatory effect of GSD was shown via iNOS and NO but not COX-2.…”

“…They are induced by lipopolysaccharides (LPSs), a major part of the gram-negative bacterial membrane, and adjust inflammation by discharging proinflammatory transmitter substances, such as inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), cyclooxygenase 2 (COX-2), tumor necrosis factor (TNF)-α, inter-leukin (IL)-1β, and IL-6 [4][5][6]. Imbalanced production of these transmitter substances results in chronic inflammatory disorders, such as various types of cancer, arteriosclerosis, diabetic nephropathy, and neurodegenerative diseases [7]. The pathological effects of inflammation on humans emphasize the need to develop safe and effective medicines that target various biochemical processes to reduce the inflammatory response.…”

Process optimization of deep eutectic solvent-based microwave-assisted extraction of flavonoids from Ziziphi Spinosae Semen using response surface methodology

“…This phenomenon may be due to the target component dissolving faster over time, but prolonged extraction can lead to changes in the molecular structure of flavonoids (Akther et al, 2021). Lee et al (2022) and Xia et al (2021) showed a similar trend of increasing and then decreasing flavonoid yield with increasing extraction time when using microwave-assisted DES to extract flavonoids. Therefore, 70 min was considered the optimal extraction time and used for further experiments.…”

Editorial for Special Issue: “Recent Advances in Green Solvents”

“…Lee et al [ 12 ] investigated the applications of deep eutectic solvents in extractions from natural leaves. They compared the efficiencies of various ratios of choline chloride and dicarboxylic acids for the extraction of flavonoid components from Pyrus ussuriensis leaves with respect to conventional solvents.…”