Comprehensive Evaluation of Deep Eutectic Solvents in Extraction of Bioactive Natural Products

Abstract

Deep eutectic solvents (DESs) are emerging as green and sustainable solvents for efficient extraction of bioactive compounds or drugs. This work aimed to comprehensively evaluate the potential and effectiveness of DESs for extraction of different types of natural compounds from biomass. Five Chinese herbal medicines including Berberidis Radix, Epimedii Folium, Notoginseng Radix et Rhizoma, Rhei Rhizoma et Radix, and Salviae Miltiorrhizae Radix et Rhizoma were selected to assess the efficiency of DESs on extraction of alkaloids, flavonoids, saponins, anthraquinones, and phenolic acids, respectively. Totally 43 types of choline chloride-, betaine-, and l-proline-based DESs with different polarity, viscosity, composition, and solubilization abilities were tailored to test their extraction efficiency, and the operation conditions were statistically optimized using response surface methodology to produce the most efficient process. In this work, DES solvents were first introduced to extract alkaloids and anthraquinones. The results indicated that most prepared DESs proved to be efficient solvents for extraction of alkaloids, but lower extractability for anthraquinones. The extraction capacity of DES may be correlated with their physical–chemical properties, including H-bonding interactions, polarity, viscosity, and pH. This study demonstrated that DESs were suitable green extraction solvents for selectively and efficiently extracting bioactive compounds from biomaterials.

Optimization of the Process Conditions for the Extraction of Rutin from <i>Ruta graveolens </i>L. by Choline Chloride Based Deep Eutectic Solvents

“…According to the data available in the literature, viscosities and/or densities for the investigated DESs are as follows: ChCl : fructose [12]. Addition of 25% and 50% of water significantly improved rutin extraction in all experiments, which could be attributed to the decrease in the viscosity of the DESs by addition of water, as described by Duan et al [6] and Zhao et al [11]. When rutin extraction yields are compared, there is no significant difference among the experiments performed with addition of 50% and 25% of water with the same DES, and, as indicated in Figure 1, there is no need to perform the extraction for 3 or 6 h.…”

“…Data in Figure 1 indicate that pure DES without addition of water has the lowest ability to extract rutin at all extraction times. This is a reasonable result since the viscosity and density of the applied DESs are high, thus causing slow mass transfer [6]. According to the data available in the literature, viscosities and/or densities for the investigated DESs are as follows: ChCl : fructose [12].…”

Natural Deep Eutectic Solvents (NADES) as a Tool for Bioavailability Improvement: Pharmacokinetics of Rutin Dissolved in Proline/Glycine after Oral Administration in Rats: Possible Application in Nutraceuticals

“…To our knowledge, no published data are available related to the in vivo effects of NADES as administration tools for bioactive constituents. These eutectics, prepared using different starting materials, can be divided into five groups, the first is based on urea (1-4), the second on polyalcohols and sugars (5-6), the third on organic acid and sugars (7)(8)(9), the fourth on organic acid and amino acid (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27), and the fifth group was prepared using choline chloride, sugars and amino acid (28)(29)(30). Our results show the ability of various NADES to dissolve rutin.…”

Deep Eutectic Solvents: An Overview of its Application as a “Green” Extractant

“…In an attempt to broaden the usage of DESs in the extraction of bioactive compounds from plants, Duan et al, [44] have used many choline chloride, betaine (Bet)-, and L-proline (Pro)-based DESs to extract alkaloids, phenolic acids, saponins, flavonoids and anthraquinones from five Chinese herbal medicines (Berberidis Radix, Epimedii Folium, Notoginseng Radix et Rhizoma, Rhei Rhizoma et Radix, and Salviae Miltiorrhizae Radix et Rhizoma).Their findings showed that most of the DESs used were more effective in extracting alkaloids than anthraquinones. The researchers concluded that the extraction ability of DES may be associated with their physicochemical properties, including hydrogen bonding interactions, polarity, viscosity, and pH.…”