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The Green, delicate and rapid ultrasound-assisted ionic liquid-based dispersive liquid-liquid microextraction technique was developed to preconcentrate trace quantities of zirconium Zr(IV) ion in real samples prior to spectrophotometric detection. The proposed method uses (1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate) ionic liquid (IL) as an extraction solvent for Zr(IV) ions after the complexation with quinalizarin at pH 5.0. The effect of various analytical parameters has been investigated. The calibration graph was linear in the range of 2.0–400 µg L − 1 and the limit of detection was 0.6 µg L-1. The preconcentration factor was 100. Relative standard deviation (RSD%) at 200 µg L-1 of Zr(IV)for intra-day and inter-day precisionwere 2.0 and 2.7%, respectively (n = 10). Certified reference materialswere used to verify the accuracy.The proposed method was applied to preconcentrate and determine the content of Zr(IV) in real environmental (water, soil and plants) samples with satisfactory results. [ABSTRACT FROM AUTHOR]

The discovery of a green extraction solvent for natural plants could promote related research. In this study, deep eutectic solvents (DES) were used as green solvents coupled with an ultrasound-assisted extraction method (UAE) to extract flavonoids from lotus leaves. Thirty-four different DES were performed and choline chloride/urea with 40% water was chosen as the most promising one, and the related parameters in the procedures were optimized, resulting in the highest extraction amount of flavonoids in lotus leaves. D-101 was selected from four macroporous resins to separate the flavonoids from DES. Moreover, DES could be recycled and efficiently reused four times with satisfactory performances. In addition, the lotus leaf flavonoids from the DES extract exhibited antioxidant activities in five kinds of assays including DPPH, ABTS, Fe3+ reducing, FRAP, and Fe2+ chelating. It also showed antibacterial activities on Staphylococcus aureus and Escherichia coli bacterial strains with minimal inhibitory concentrations at 1666 μg/mL and 208 μg/mL, respectively. In the HPLC analysis, the three main components in the DES extract were identified as astragalin, hyperoside, and isoquercitrin. In conclusion, the developed UAE-DES followed by macroporous resin treatment could become an efficient and environmentally friendly extraction and enrichment method for flavonoids from lotus leaves and other natural products. [ABSTRACT FROM AUTHOR]

• Design and synthesis of low viscosity, highly soluble and hydrophilic new ternary deep eutectic solvent. • First extraction of polyphenolic active compounds from Paeonia lactiflora. • New ternary deep eutectic solvent with higher extraction efficiency than conventional solvent. • Deep eutectic solvent extracts have higher antioxidant activity and reducing power than traditional solvent extracts. Study has demonstrated that Paeonia lactiflora contains a significant number of polyphenolic compounds; however, there is little research literature focus on phenolic acids in Paeonia lactiflora. In this study, an ultrasound-assisted extraction method based on ternary DESs was developed for the extraction of biologically active polyphenols in Paeonia lactiflora. The results indicated that the ternary solvent composed of choline chloride, DL-lactic acid, and 1,2-propanediol in a molar ratio of 1:4:2 achieved a superior extraction of polyphenols than that of conventional solvents and other ternary solvents. Subsequently, the response surface method was used to optimize the selected parameters of solid–liquid ratio, extraction time, and temperature for the extraction of phenolic by the DES, and the optimal extraction conditions were as follows: a solid–liquid ratio of 1:13.8 g/mL, an extraction time of 47.5 min, and an extraction temperature of 34.5 °C, with a total polyphenol yield of 79.77 mg/g, which is 1.09 times that of the traditional solvent. Furthermore, the extract of Paeonia lactiflora obtained through the DES method exhibited promising in vitro antioxidant activity and reducing ability. Studies have shown that DES is an efficient and environmentally friendly extraction solvent for extracting polyphenols from natural products, providing a new direction for the development and industrial production of Paeonia lactiflora. [ABSTRACT FROM AUTHOR]

An environmentally friendly, sensitive, easy and fast ultrasound-assisted ionic liquid-based dispersive liquid-liquid microextraction technique (UA-IL-DLLME) was developed to preconcentrate trace quantities of nickel Ni(II) ion in water, food and tobacco samples prior to detection by FAAS. The proposed technique based on utilisationthe of ionic liquid (IL) (1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate [HMIM][FAP]) as an extraction solvent for Ni(II) ions after the complexation with quinalizarin (Quinz) at pH 6.0. The impact of different analytical parameters on the microextraction efficiency was investigated. In the range of 2.0–300 µg L−1, the calibration graph was linear. Limit of detection and preconcentration factor were 0.6 µg L−1 and 100. Relative standard deviation (RSD%) as precision at 50 and 100 µg L−1 of Ni(II) were 2.4% and 3.6%, respectively (n = 10). The validation of the proposed procedure was verified by a test of two certified reference materials (TMDA-51.3 fortified water, TMDA-53.3 fortified water and SRM spinach leaves 1570A) applying the standard addition method. Finally, the proposed UA-IL-DLLME method was developed and applied to preconcentrate and determine of trace quantities of Ni(II) in real water, food and tobacco samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Lantana camara is known to have anti-bacterial properties which can be exploited to develop a natural food preservative. There is huge demand for natural preservatives in food industry due to the increased health risks associated with synthetic preservatives, development of efficient extraction methods are essential to retain heat sensitive bioactive compounds. The aim of this study was to compare the performance of microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and conventional solvent extraction (CSE) methods for extraction of freeze-dried lantana flower. The phytochemicals in freeze-dried flowers were characterized by GC-MS analysis and antibacterial properties were tested at different concentrations (50, 100, and 150 μl) against E.coli, Salmonella, and S. aureus. It was evident that the UAE offered the highest yield (64%), followed by MAE (53%) and CSE (49%) with distilled water as solvent. The freeze-dried extract possessed a high amount of tannins (417 μg/g), followed by flavonoids such as catechol (88 μg/g) and quercetin (9.2 μg/g). The antibacterial potential results revealed that only distilled water-based extraction techniques offered positive inhibition zones of 2.0-2.67 mm (MAE), 1.67-2.67 mm (UAE), and 1.67-2.17 mm (CSE) against all three organisms, while the chloroform based extracts had no inhibition effect. The microwave-assisted extract at 150 μl concentration offered a significant inhibitory effect against all three pathogens. The GC-MS profiling of bioactive compounds in flower extract revealed the presence of hexadecanoic acid as the major phytochemical compound in all three extraction techniques. The study revealed that the chloroform extract failed to exhibit an antibacterial effect due to the absence of alkaloids, saponins, and anthraquinones as a result of its neutralizing effect. [ABSTRACT FROM AUTHOR]

The ultrasound-assisted extraction process of vanadium from the aqueous phase to the organic phase by methyltrioctylammonium chloride (MAC) was studied. The factors that influence the vanadium extraction rate such as stirring speed, temperature, and ultrasound power were investigated. The rate expression of vanadium extraction with ultrasound was established. The extraction process could consist of diffusion and chemical capturing steps at the aqueous-organic interface. This study demonstrated that the diffusion resistance could be eliminated by increasing the stirring speed and ultrasound power. The vanadium extraction process without diffusion resistance conformed to the first-order kinetic model. The activation energy (E a) of this extraction process was determined as 36.7 kJ mol−1 along with a pre-exponential factor k 0 a as 3.27 × 105 s−1, while the ultrasound enhancement factor can be expressed as ε = 1 + 1.40 × 10−2 P - 6.61 × 10−5 P 2. The optimal extraction kinetics are identified by examining the factors affecting the vanadium extraction rate (r extr), which are stirring speed ≥ 200 rpm, ultrasound power (P) = 90 W, extraction temperature (T) = 318.15 K. This study provides a theoretical basis for the extraction process of vanadium and aids the design of ultrasound-assisted extraction applications. [Display omitted] • A kinetic model for ultrasonic vanadium extraction was established. • An enhancement mechanism of ultrasonic vanadium extraction was determined. • A quantitative relationship among the ka ε, P , and T was illustrated. [ABSTRACT FROM AUTHOR]

The effects of ultrasound-assisted, supercritical CO2and solvent extraction methods on antioxidant activity ofZiziphus mauritiana(Lam.) extracts were investigated using 2,2-diphenyl-1-picrylhydrazyl and β-carotene assays. Ethanol-water extract of the jujube that was obtained with ultrasound-assisted extraction had the highest antioxidant activity. Ultrasound-assisted extraction was the most effective method on extraction of phenolic compounds. The effect of ultrasound extract in stability of soybean oil was compared to synthetic antioxidants by measuring total polar compounds, carbonyl value, peroxide value, free fatty acids, oxidative stability index, and conjugated dienes and trienes values. Results showed that ultrasound ethanol-water extract at 600 ppm had a higher stabilization efficiency than commercial antioxidants butylated hydroxyanisole, butylated hydroxytoluene, and tertiary butylhydroquinone. [ABSTRACT FROM PUBLISHER]

In this study, the bioactive compounds of loquat fruit ( Eriobotrya japonica Lindl.) skin and pulp extracted by two extraction methods (solvent and ultrasound-assisted) with three solvents (ethanol, water and ethanol-water) were compared to supercritical fluid extraction. The antioxidant activities of skin and pulp extracts were evaluated and compared to tertiary butylhydroquinone ( TBHQ) using 2, 2-diphenyl-1-picrylhydrazyl ( DPPH˙) radical scavenging, β-carotene bleaching, and the Rancimat assays. In DPPH assay solvent extracts of skin by ethanol ( SSE) and ethanol-water ( SSEW) showed strong inhibitory activity. The SSEW also showed the highest inhibition percentage of 85.58% by the β-carotene bleaching assay and longest induction time of 4.78 h by the Rancimat method. The large amount of tocopherols and phenolics contained in the skin extract may cause its strong antioxidant ability. The results indicated that the solvent extraction with ethanol-water produced the maximum extraction yield of phenolic and tocopherol compounds from loquat fruit skin and pulp. Furthermore, solvent extraction was the most effective in antioxidant activity of the extracts compared to other extraction techniques. [ABSTRACT FROM AUTHOR]

Solvent extraction, ultrasound assisted extraction (UAE), and microwave assisted extraction (MAE) were examined for the extraction of astaxanthin from Haematococcus pluvialis. In all cases, acetone was found to give the highest astaxanthin recovery compared with other selected solvents, i.e., methanol, ethanol, and acetonitrile. Among the various methods, MAE at 75°C for 5 min resulted in the highest astaxanthin recovery (74 ± 4%). [ABSTRACT FROM AUTHOR]

• Important factors affecting the extraction efficiency of Cd(II) were successfully scrutinized. • Low LOD (0.3 ng mL−1), high EF (165), and good precision (RSD < 2.5%) were obtained. • An overview of the extraction of Cd(II) in real samples by the UA-alkanol-based-SUPRAS-ME was presented. • Consisting of spherical micelle of 1-tetradecanol, SUPRAS was easily prepared. • Current method was applied to water, vegetable, and food samples. Herein, a new and green analytical method was described for extraction and determination of cadmium in food and environmental samples using ultrasound assisted alkanol-based nano structured supramolecular solvent microextraction (UA-alkanol-based-SUPRAS-ME) coupled with flame atomic absorption spectrometry (FAAS) detection. The SUPRAS was easily prepared from reverse micelles of 1-tetradecanol (as extraction solvent) in tetrahydrofuran (THF as dispersive solvent). The Box-Behnken design based on the analysis of variance and the desirability function guide was used to optimize the key variables (pH, SUPRAS volume, ligand amount, ultrasonic time) of the UA-alkanol-based-SUPRAS-ME procedure. Under the optimum conditions, the calibration graphs were linear in the range of 50–3500 µg kg−1 and 1–400 ng mL−1 for foods and environmental samples, respectively. Acceptable limits of detection (LODs) of 15 µg kg−1 and 0.3 ng mL−1 were calculated for food and environmental samples, respectively. Inter day RSDs% lower than 4.9% with an average recovery of 99.8%, and intraday RSDs% lower than 4.1% with an average recovery of 97% were obtained. Total cadmium was determined in the range of 48.2–186.4 µg kg−1 and 35.4–124.6 ng mL−1 in food and environmental samples, respectively. [ABSTRACT FROM AUTHOR]

• The 82.8 % (w/w) of biooil yield was obtained from C. inophyllum L. seeds. • An equal ratio of diethyl ether and ethanol was found best for bioil extraction. • Biooil was characterized using GC–MS and FTIR and oil contains 22.11 % of FFA. • Technoecconomic analysis of oil extraction was investigated using SuperPro. In the present investigation, the bio-oil extraction from Calophyllum inophyllum seeds using an ultrasonic-assisted heterogeneous solvent technique has been carried out in order to avoid diminishing the oil property and quality by high temperature. The application of different combinations of solvent extraction has been examined using Diethyl ether:Ethanol, Chloroform:Methanol, and Isopropanol: Methanol. The results reveals that the equal ratio of Diethyl ether:Ethanol in assistance with ultrasonic waves yields maximum oil extraction. The other optimized process conditions determined by central composite design was found to be the seed kernel to the solvent ratio of 1:15 (w:v); time 45 min; temperature 36 °C and ultrasonication power of 54 % yields maximum bio-oil of 82.8 % (w/w). The kinetic study denotes that the oil extraction process follows first-order kinetics. The presence of different functional groups, as well as volatile compounds in the extracted oil, were confirmed by fourier-transform infrared spectroscopy and gas chromatography-mass spectrometry. This confirms the presence of 22.11 % of free fatty acid content in the extracted bio-oil. The techno-economic analysis of 4.4 million kg of oil extract plant was investigated. The annual revenue estimated from the oil is 2,097,000 $/yr and the payback period is 5.43 years. [ABSTRACT FROM AUTHOR]