Optimization of Extraction of Bioactive Compounds from Baphicacanthus cusia Leaves by Hydrophobic Deep Eutectic Solvents

Abstract

Deep eutectic solvents (DESs) are considered as efficient and green solvents for the extraction of bioactive compounds from medicinal plants. In this work, a novel method of DES-based ultrasound-assisted extraction of bioactive compounds from Baphicacanthus cusia leaves (BCL) was established. Systematic screening and the morphology of the original and treated BCL were observed with scanning electron microscopy to determine the extraction efficiency of different solvents. The extraction conditions were optimized by Box–Behnken design (BBD) tests and the optimal extraction conditions were as follows: lactic acid/L-menthol ratio of 5: 2 (mol/mol), solid–liquid ratio of 80.0 mL/g and temperature of 60.5 °C. The extraction yields of tryptanthrin, indigo and indirubin reached 0.356, 1.744 and 0.562 mg/g, respectively. The results of a 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity test indicated the feasibility of DESs in the extraction of bioactive compounds. This study indicated that L-menthol/lactic acid was a green and efficient solvent for the extraction of bioactive compounds from BCL, and DES-based ultrasound-assisted extraction could be used as an effective application strategy for the extraction of bioactive compounds from medicinal plants.

DES Based Efficient Extraction Method for Bioactive Coumarins from Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav.

“…By contrast, the outer surface of the sample powder was significantly cracked by pulsed ultrasonic treatment, and loose and broken structures could be observed. This is similar to what Sukor et al observed when extracting phenolic acids using ultrasonic processing of an ionic liquid probe [28], and Chen et al used ultrasoundassisted extraction methods for imperatorin and isoimperatorin from A. dahurica roots [22].…”

“…DPPH has been widely used to determine the antioxidant capacity of biological samples, pure compounds, and extracts in vitro. This method is simple and can be used to evaluate the antioxidant activity of the samples [28]. With VC as the control, the DPPH radical scavenging activities of the two different treated solutions are shown in Figure 11.…”

Ultrasonic-Assisted Efficient Extraction of Coumarins from Peucedanum decursivum (Miq.) Maxim Using Deep Eutectic Solvents Combined with an Enzyme Pretreatment

“…DPPH has been widely used to determine the antioxidant capacity of biological samples, pure compounds and extracts in vitro. The method is simple and can be used to evaluate the antioxidant activity of samples [ 43 , 44 ]. In this study, the antioxidant activities of the enzyme-assisted extracts of three different extraction solvents (methanol, 70% ethanol and DESs) were compared.…”

Application of an alkali destruction technique and natural deep eutectic solvent for greener extraction from peanut shells: optimization and extraction kinetics study

“…37 Then, the increase in temperature accelerated the intermolecular movement of the flavonoids, which promoted the transfer of the flavonoids from the cells to Me/LA. 38 Finally, excessive temperature would not only lead to the reduction of the NADES polarity, but also accelerate the thermal decomposition rate of the flavonoids, so the extraction efficiency was at a maximum at 80 °C. 39 Therefore, 80 °C was selected as the best extraction temperature condition for the follow-up experiments.…”