Towards green analysis of curcumin from tea, honey and spices: Extraction by deep eutectic solvent assisted emulsification liquid-liquid microextraction method based on response surface design

Differential Extraction and Preliminary Identification of Polyphenols from Ugni candollei (White Murta) Berries

Ugni candollei, commonly known as white murta, is a native Chilean berry with a polyphenol composition that has been underexplored. This study aimed to establish a comprehensive profile of white murta polyphenols using ultra-performance liquid chromatography electrospray ionization Orbitrap mass spectrometry (UPLC-ESI-ORBITRAP MS). Additionally, it compared the efficacy of conventional extraction methods with emerging techniques such as deep eutectic solvent (DES) extraction and hot pressurized water extraction (HPWE). The analysis tentatively identified 107 phenolic compounds (84 of them reported for the first time for this cultivar), including 25 phenolic acids, 37 anthocyanins, and 45 flavonoids. Among the prominent and previously unreported polyphenols are ellagic acid acetyl-xyloside, 3-p-coumaroylquinic acid, cyanidin 3-O-(6'-caffeoyl-glucoside, and phloretin 2'-O-xylosyl-glucoside. The study found HPWE to be a promising alternative to traditional extraction of hydroxybenzoic acids, while DES extraction was less effective across all categories. The findings reveal that white murta possesses diverse phenolic compounds, potentially linked to various biological activities.

Greener Stability-Indicating HPLC Approach for the Determination of Curcumin in In-House Developed Nanoemulsion and Curcuma longa L. Extract

Despite the fact that several analytical methodologies have been reported for the determination of curcumin (CCM) in a wide range of sample matrices, the greener liquid chromatographic approaches to determine CCM are scarce in the literature. Therefore, this research is designed to develop and validate a greener stability-indicating “high-performance liquid chromatography (HPLC)” methodology to determine CCM in an in-house developed nanoemulsion, Curcuma longa L. extract, and commercial tablets. CCM was measured on a Nucleodur (150 mm × 4.6 mm) RP C18 column with 5 µm-sized particles. Ethanol and ethyl acetate (83:17 v/v) made up the greener eluent system, which was pumped at a flow speed of 1.0 mL/min. At a wavelength of 425 nm, CCM was detected. The greener HPLC methodology was linear in the 1–100 µg/mL range, with a determination coefficient of 0.9983. The greener HPLC methodology for CCM estimation was also rapid (Rt = 3.57 min), accurate (%recoveries = 98.90–101.85), precise (%CV = 0.90–1.11), and sensitive (LOD = 0.39 µg/mL and LOQ = 1.17 µg/mL). The AGREE approach predicted the AGREE score of 0.81 for the established HPLC technique, indicating an outstanding greenness profile. The utility of the greener HPLC methodology was demonstrated by determining CCM in the in-house developed nanoemulsion, Curcuma longa extract, and commercial tablets. The % amount of CCM in the in-house developed nanoemulsion, Curcuma longa extract, and commercial tablets was found to be 101.24%, 81.15%, and 78.41%, respectively. The greener HPLC methodology was able to detect its degradation product under various stress conditions, suggesting its stability-indication characteristics. These results suggested that CCM in developed nanoemulsion, plant extract samples, and commercial tablets may be routinely determined using the greener HPLC methodology.

Hydrophobic deep eutectic solvent-based ultrasonic-assisted liquid-liquid microextraction combined with GC for eugenol, isoeugenol, and methyl isoeugenol determination in aquatic products

The use of deep eutectic solvents (DESs) has great prospects because of the green and efficient characteristics, which can be used for developing analytical methods for foods. In this research, assisted by ultrasonic waves, a liquid-liquid microextraction detection method combined with gas chromatography was established for three anaesthetics (eugenol, isoeugenol, and methyl isoeugenol) in aquatic food. The processing conditions including the components, ratio of hydrogen bond acceptor and hydrogen bond donor, DES volume, ultrasonic time, and pH were evaluated and optimised to improve the extraction efficiency, which was based on the DES structures and properties. In-house method validation was carried out by applying to real samples. A Thymol: levulinic acid DES (with a molar ratio of 1:2) was used as the extractant and the recoveries were as high as 93-101% for eugenol, 90-100% for methyl isoeugenol, and 86-94% for isoeugenol with RSDs <5% under optimum conditions. The limit of detection and quantification of the eugenol compounds were 0.08-0.10 μg/mL and 0.26-0.33 μg/mL, respectively. The method has green credentials and comparable LOD to homologous apparatus, which can be used for the determination of eugenol components in aquatic food.

Antimicrobial and antiviral activity of selenium sulphide nanoparticles synthesised in extracts from spices in natural deep eutectic solvents (NDES)

Selenium sulphide is a well-known bioactive chemical, but its preparation in nanometric form stabilised in water has not been widely reported. In the article, extracts of cinnamon, curcumin, and pepper obtained using natural deep eutectic solvents (NDES) were used to obtain stable selenium sulphide nanoparticles. The analysis confirmed that selenium sulphide nanoparticles with an average crystallite size of 28–44 nm and a particle size of approximately 500 nm were successfully synthesised. The use of NDES stabilised the SeS₂ nanoparticles and increased their bioactivity towards microorganisms. The obtained systems revealed high biocidal and antiviral activity against S. aureus, E. coli, P. aeruginosa, and C. albicans strains, Human influenza virus A/H1N1, and Betacoronavirus 1 (Human coronavirus HCoV-OC43). The SeS₂ nanoparticles obtained in the NDES extract of curcuma strongly inhibited the growth of pathogenic fungi and bacteria with minimum biocidal concentration (MBC) values of 117.2, 117.2, 117.2, and 468.8 mg/dm³ against E. coli, P. aeruginosa, S. aureus, and C. albicans, respectively. The suspensions containing selenium sulphide nanoparticles stabilised by spice extracts were also highly active against influenza viruses and B-coronavirus, showing a reduction of over 99%.

Deep Eutectic Solvents Application in Food Analysis

Current trends in Analytical Chemistry are focused on the development of more sustainable and environmentally friendly procedures. However, and despite technological advances at the instrumental level having played a very important role in the greenness of the new methods, there is still work to be done regarding the sample preparation stage. In this sense, the implementation of new materials and solvents has been a great step towards the development of "greener" analytical methodologies. In particular, the application of deep eutectic solvents (DESs) has aroused great interest in recent years in this regard, as a consequence of their excellent physicochemical properties, general low toxicity, and high biodegradability if they are compared with classical organic solvents. Furthermore, the inclusion of DESs based on natural products (natural DESs, NADESs) has led to a notable increase in the popularity of this new generation of solvents in extraction techniques. This review article focuses on providing an overview of the applications and limitations of DESs in solvent-based extraction techniques for food analysis, paying especial attention to their hydrophobic or hydrophilic nature, which is one of the main factors affecting the extraction procedure, becoming even more important when such complex matrices are studied.

An environment-friendly and rapid liquid-liquid microextraction based on new synthesized hydrophobic deep eutectic solvent for separation and preconcentration of erythrosine (E127) in biological and pharmaceutical samples

In this study, a new deep eutectic solvent (DES) consist of tetrabuthylammonium bromide (TBABr) and 1-octanol at 1:2 M ratio was prepared for the first time and characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (¹H NMR) and carbon nuclear magnetic resonance (¹³C NMR) techniques. The new DES was used as an extraction solvent in the ultrasound assisted liquid-liquid microextraction (UA-LLME) of Erythrosine (E127) in blood, urine, pharmaceutical tablet and syrup samples. Accurate and sensitive determination of erythrosine was accomplished with the combination use of DES-UA-LLME and UV-Vis spectrophotometric detection. Before applying UA-LLME, while protein precipitation was applied to blood samples, pharmaceutical tablets were homogenized and dissolved in methanol. The proposed DES-UA-LLME/UV-VIS procedure was applied directly to urine, syrup sample and supernatant of blood and tablet samples with high recoveries in range of 90% and 100%. Erythrosine in the aqueous sample phase was extracted into 200 μL hydrophobic DES phase at pH 7.0. The effect of important analytical variables such as pH of sample solution, mol ratio of DES components, volume of DES, ultrasonic-based extraction time, sample volume and salt effect were optimized. The preconcentration factor (PF), limit of detection (LOD), intra-day and inter-day relative standard deviations (RSD, %) for the developed procedure were found as 40, 3.75 μg·L^-1, 2.6% and 4.6%, respectively.

An environmentally friendly and novel amine-based liquid phase microextraction of quercetin in food samples prior to its determination by UV-vis spectrophotometry

A novel and environmentally-friendly method, which includes determination of trace amounts of quercetin in samples by using UV-vis spectrophotometry after enrichment with amine-based liquid phase microextraction (LPME), has been developed. As extraction solvent, N,N-dimethyl-n-octylamine has been used and the quercetin concentration in extraction phase was determined by UV-vis spectrophotometry at 382.5 nm. Important analytical parameters such as pH, extraction solvent type and volume, sample volume, extraction time were optimized by the method. Quercetin in the sample solution was extracted to 200 μL of N,N-dimethyl-n-octylamine phase at pH 4.0. The detection limit (LOD) and the quantitation limit (LOQ) values for quercetin were calculated as 0.07 μg·mL^-1 and 0.24 μg·mL^-1, respectively. Accuracy studies for the food samples was carried out by addition and recovery experiments. The developed method has been successfully applied to different food samples including spinach, green pepper, red onion and dill weed.

A Review of the Use of Eutectic Solvents, Terpenes and Terpenoids in Liquid–liquid Extraction Processes

Diverse and abundant applications of the eutectic solvents have appeared in the last years. Their promising tunable properties, eco-friendly character and the possibility of being prepared from numerous compounds have led to the publication of numerous papers addressing their use in different areas. Terpenes and terpenoids have been employed in the formulation of eutectic solvents, though they also have been applied as solvents in extraction processes. For their hydrophobic nature, renewable character, low environmental impact, cost and being non-hazardous, they have also been proposed as possible substitutes of conventional solvents in the separation of organic compounds from aqueous streams, similarly to hydrophobic eutectic solvents. The present work reviews the application of eutectic solvents in liquid–liquid extraction and terpenes and terpenoids in extraction processes. It has been made a research in the current state-of-the-art in these fields, describing the proposed applications of the solvents. It has been highlighted the scale-up feasibility, solvent regeneration and reuse procedures and the comparison of the performance of eutectic solvents, terpenes and terpenoids in extraction with conventional organic solvents or ionic liquids. Ultimately, it has been also discussed the employ of predictive methods in extraction, the reliability of thermodynamic models in correlation of liquid–liquid equilibria and simulation of liquid–liquid extraction processes.

Properties, Extraction Methods, and Delivery Systems for Curcumin as a Natural Source of Beneficial Health Effects

This review discusses the impact of curcumin-an aromatic phytoextract from the turmeric (Curcuma longa) rhizome-as an effective therapeutic agent. Despite all of the beneficial health properties ensured by curcumin application, its pharmacological efficacy is compromised in vivo due to poor aqueous solubility, high metabolism, and rapid excretion that may result in poor systemic bioavailability. To overcome these problems, novel nanosystems have been proposed to enhance its bioavailability and bioactivity by reducing the particle size, the modification of surfaces, and the encapsulation efficiency of curcumin with different nanocarriers. The solutions based on nanotechnology can improve the perspective for medical patients with serious illnesses. In this review, we discuss commonly used curcumin-loaded bio-based nanoparticles that should be implemented for overcoming the innate constraints of this natural ingredient. Furthermore, the associated challenges regarding the potential applications in combination therapies are discussed as well.