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. 2021 Jul 27;11(42):25983-25994.
doi: 10.1039/d1ra03840k.

The application of amino acid ionic liquids as additives in the ultrasound-assisted extraction of plant material

Barbara Roman  1 , Anna Muzykiewicz-Szymańska  2 , Paula Ossowicz-Rupniewska  1 , Adam Klimowicz  2 , Ewa Janus  1
Affiliations

The application of amino acid ionic liquids as additives in the ultrasound-assisted extraction of plant material

Barbara Roman et al. RSC Adv. .

Abstract

The aim of the present study was to determine the antioxidant activity of the aqueous extracts from Lycopodium clavatum, Cetraria islandica and Dipsacus fullonum obtained using aqueous solutions of ionic liquids by the ultrasound-assisted extraction (IL-UAE) method. Triethanolammonium salts [TEAH]+[AA]- of four amino acids of different hydrophobicity - isoleucine - Ile, methionine - Met, threonine - Thr and arginine - Arg, were chosen as ionic liquids, because they are based on natural, bio-renewable raw materials, such as amino acids and contain a pharmaceutically and cosmetically acceptable counterion of triethanolamine. Triethanolammonium salts were synthesized, identified by spectroscopic methods (NMR and FT-IR) and characterized by thermal methods (DSC and TGA). The 2.5% w/v aqueous solutions of triethanolammonium amino acid salts were used as the solvents in combination with ultrasound assisted extraction (UAE). The estimation of antioxidant properties was carried out using the DPPH, FRAP and CUPRAC assays. Total polyphenol content was measured using the reagent Folin-Ciocalteu. The results showed that the use of [TEAH]+[Thr]- or [TEAH]+[Met]- aqueous solutions increased the antioxidant activity of extracts in comparison to that achieved for extracts with pure water. The use of [TEAH]+[Thr]- as an additive for ultrasound-assisted extraction was characterized by obtaining plant extracts with the highest antioxidant potential, even 2.4-fold. The use of the AAIL-UAE method allowed obtaining higher amounts of polyphenols compared to pure water extracts, even 5.5-fold. The used method allowed the extraction of thermosensitive natural compounds, shortened the extraction time and lowered energy consumption.

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Conflict of interest statement

There are no conflicts of interest to declare.

Figures

Fig. 1
Fig. 1. Antioxidant activity of extracts obtained from L. clavatum with water and aqueous solutions of [TEAH]+[Thr]−, [TEAH]+[Met]−, [TEAH]+[Arg]− and [TEAH]+[Ile]−, as extraction media, determined by the DPPH method in preliminary studies.
Fig. 2
Fig. 2. Antioxidant activity of extracts obtained from C. islandica and D. fullonum with water and aqueous solutions of [TEAH]+[Thr]− or [TEAH]+[Met]−, as extraction media, determined by the DPPH method.
Fig. 3
Fig. 3. Antioxidant activity of extracts obtained from L. clavatum, C. islandica and D. fullonum, with water and aqueous solutions of [TEAH]+[Thr]− or [TEAH]+[Met]−, as extraction media, determined by the FRAP method.
Fig. 4
Fig. 4. Antioxidant activity of extracts obtained from L. clavatum, C. islandica and D. fullonum, with water and aqueous solutions of [TEAH]+[Thr]− or [TEAH]+[Met]−, as extraction media, determined by the CUPRAC method.
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References

    1. Vinardell M. P. Mitjans M. Nanocarriers for Delivery of Antioxidants on the Skin. Cosmetics. 2015;2:342–354. doi: 10.3390/cosmetics2040342. doi: 10.3390/cosmetics2040342. - DOI
    1. Nimse S. B. Pal D. Free radicals, natural antioxidants, and their reaction mechanisms. RSC Adv. 2015;5:27986–28006. doi: 10.1039/c4ra13315c. doi: 10.1039/C4RA13315C. - DOI
    1. Roman B. Retajczyk M. Sałaciński Ł. Pełech R. Curcumin – Properties, Applications and Modification of Structure. Mini-Rev. Org. Chem. 2020;17:486–495. doi: 10.2174/1570193X16666190621110247. doi: 10.2174/1570193X16666190621110247. - DOI
    1. Wang L. Weller C. L. Recent advances in extraction of nutraceuticals from plants. Trends Food Sci. Technol. 2006;17:300–312. doi: 10.1016/j.tifs.2005.12.004. doi: 10.1016/j.tifs.2005.12.004. - DOI
    1. Stalikas C. D. Extraction, separation, and detection methods for phenolic acids and flavonoids. J. Sep. Sci. 2007;30:3268–3295. doi: 10.1002/jssc.200700261. doi: 10.1002/jssc.200700261. - DOI - PubMed