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

Abstract

In this study, natural deep eutectic solvents (NADES) formed by choline chloride (ChCl), sucrose, fructose, glucose, and xylose, were used to extract antioxidants from the halophyte Polygonum maritimum L. (sea knotgrass) and compared with conventional solvents (ethanol and acetone). NADES and conventional extracts were made by an ultrasound-assisted procedure and evaluated for in vitro antioxidant properties by the radical scavenging activity (RSA) on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, oxygen radical absorbance capacity (ORAC), and copper chelating activity (CCA). Samples were profiled by liquid chromatography (LC)-electrospray ionization (ESI)-QTOF-MS analysis. ChCl:fructose was more efficient in the DPPH assay, than the acetone extract. ChCl:sucrose and ChCl:fructose extracts had the highest ORAC when compared with the acetone extract. NADES extracts had higher CCA, than the acetone extract. The phenolic composition of the NADES extracts was less complex than the conventional extracts, but the proportions of major antioxidants, such as flavonols and flavan-3-ols, were similar in all the solvents. Myricitrin was the major flavonoid in all of the samples, while gallic acid was the main phenolic acid in the conventional extracts and present in a greater amount in ChCl:fructose. Results suggest that NADES containing ChCl and sucrose/fructose can replace conventional solvents, especially acetone, in the extraction of antioxidants from sea knotgrass.

Optimization of Extraction of Phlorotannins from the Arctic Fucus vesiculosus Using Natural Deep Eutectic Solvents and Their HPLC Profiling with Tandem High-Resolution Mass Spectrometry

“…The NADES extracts of Polygonum maritimum were found to be rich in phenolic compounds, and, therefore, were potent antioxidants in vitro. In particular, the NADES (choline chloride (ChCl) and sucrose (Suc)) extract was more efficient in the scavenging of DPPH radicals and oxygen radical absorbance capacity test, as compared to the acetone extracts [ 57 ]. The NADES extracts of onion peel prepared with ChCl, Suc, urea and sorbitol had a significant (2–5-fold) higher iron reduction capacity than that of the aqueous methanol extract.…”

The genus Polygonum: An updated comprehensive review of its ethnomedicinal, phytochemical, pharmacological activities, toxicology, and phytopharmaceutical formulation

“…Quercetin is the most detected compound in the genus Polygonum . It is found in ten species, among them P. aviculare [ 37 , 54 ] , P. bistorta [ 38 ], P. equisetiforme [ 15 , 46 ], P. maritimum [ 55 ] , P. multiflorum [ 47 ] , and other species. Quercetin is a highly important chemical found in plants.…”

“…Additionally, it has shown a wide range of anticancer properties, and multiple studies support its effectiveness as a treatment for cancer prevention [ 26 ]. Catechin and epicatechin are two flavonoid compounds that were detected in various Polygonum species ( P. aviculare, P. cuspidatum, P. equisetiforme, P. maritimum, P. multiflorum, and P. paleaceum ) [ 15 , 38 , 40 , 46 , [55] , [56] , [57] , [58] , [59] ]. These compounds are two flavonoids stereoisomers that are highly prevalent in vegetable tissues and exhibit strong antioxidant properties in live organisms.…”

The Most Potent Natural Pharmaceuticals, Cosmetics, and Food Ingredients Isolated from Plants with Deep Eutectic Solvents

“…They have very good antioxidative and antimicrobial properties, which makes them promising natural preservatives. Examples of flavonoid extraction with DESs from plant material are presented in Table . ,,,,,,,− …”