Natural Deep Eutectic Solvents for the Extraction of Bioactive Steroidal Saponins from Dioscoreae Nipponicae Rhizoma

Abstract

In the present study, a simple and environmentally friendly extraction method based on natural deep eutectic solvents (NADESs) was established to extract four bioactive steroidal saponins from Dioscoreae Nipponicae Rhizoma (DNR). A total of twenty-one types of choline chloride, betaine, and L-proline based NADESs were tailored, and the NADES composed of 1:1 molar ratio of choline chloride and malonic acid showed the best extraction efficiency for the four steroidal saponins compared with other NADESs. Then, the extraction parameters for extraction of steroidal saponins by selected tailor-made NADES were optimized using response surface methodology and the optimal extraction conditions are extraction time, 23.5 min; liquid–solid ratio, 57.5 mL/g; and water content, 54%. The microstructure of the DNR powder before and after ultrasonic extraction by conventional solvents (water and methanol) and the selected NADES were observed using field emission scanning electron microscope. In addition, the four steroidal saponins were recovered from NADESs by D101 macroporous resin with a satisfactory recovery yield between 67.27% and 79.90%. The present research demonstrates that NADESs are a suitable green media for the extraction of the bioactive steroidal saponins from DNR, and have a great potential as possible alternatives to organic solvents for efficiently extracting bioactive compounds from natural products.

Extraction of Bioactive Compounds From Cannabis sativa L. Flowers and/or Leaves Using Deep Eutectic Solvents

“…To date, numerous articles detailing the use of these solvents as extraction (phenolic acids, flavonoids, and polyphenols) and separation media (dissolving lignocelluloses, separation of an azeotropic mixture, and solid-liquid extraction) are reported in the literature ( 20 – 22 ). The extraction of a solid sample involves the transfer of the analyte to the liquid phase through diffusion or solvation- desorption mechanisms, and the selection of the solvent used depends on the characteristics of the matrix and the analyte.…”

Efficacy of Natural Deep Eutectic Solvents for Extraction of Hydrophilic and Lipophilic Compounds from Fucus vesiculosus

“…To be predominantly polar liquids, NADES have been used for the extraction of alkaloids [6], anthocyanins [7][8][9], glycosides of phenyletanes and phenylpropanoids [10], and polysaccharides [11]. NADES could be customized for the extraction of less polar aglycones of flavonoids [12], anthraquinones [13], astaxanthin [14], curcumin [15], glycyrrhizic acid [16], iridoids [17], and steroidal saponins [18]. Hydrophobic terpenes and fatty acid-based NADES allowed for the isolation of carotenoids, free fatty acids, and pheophytin [19].…”

Greener Is Better: First Approach for the Use of Natural Deep Eutectic Solvents (NADES) to Extract Antioxidants from the Medicinal Halophyte Polygonum maritimum L.

“…), plum (Prunus sp. ), rosemary (Salvia rosmarinus), and pepper (Piper nigrum) [18][19][20], phenolic acids from Lonicerae japonicae [1], polyphenols from dittany (Origanum dictamnus), marjoram (Origanum majorana), mint (Mentha spicata), sage (Salvia officinalis), and fennel (Foeniculum vulgare) [21], phenylethanes and phenylpropanoids from Rhodiola rosea L [22], and steroidal saponins from Dioscoreae nipponicae rhizome [23].…”