Solvent Extraction Technique Research Articles

Microplastics detection in some cosmetic samples by Accelerated Solvent Extraction and Micro-FTIR

Worldwide attention is focused on microplastics environmental pollution, primarily for its potential negative effects on biota and human health. It is of great importance to identify standardized analytical methods to have an objective feedback about this concern. The recent regulation regarding the intentionally added microplastics content and the attention for the unintentional microplastics release are the basis of this work, whose topic is the development of an analytical method for microbeads (spheres) and microparticles (fragments) determination in certain cosmetic samples, in particular creamy samples. The method is based on Accelerated Solvent Extraction technique to remove all the sample matrix ingredients. The final suspension was then filtered on silicon membrane, for the following quali-quantitative micro-FTIR analysis, and on glass fibre membranes, for the gravimetric analysis. The method was developed for a theoretical microplastics concentration of 0.025 % (w/w) and allows a good recovery percentage. Working both by gravimetric evaluation and by micro-FTIR analysis gives more confident results and guaranties a proper identification and characterization of the filtered materials.

Green and sustainable recovery of polyphenols, flavonoids, alkaloids, and pigments from green tea leaves: Comparative analysis of Soxhlet, accelerated solvent, and supercritical fluid extraction techniques

The growing interest in green tea extracts for their applications in pharmaceutical, food, and cosmetic industries underscores the need for environmentally sustainable extraction methods. This study presents optimized strategies for the green recovery of bioactive compounds from Gun powder green tea leaves using Soxhlet extraction, accelerated solvent extraction, and supercritical fluid extraction techniques. By varying extraction solvents (supercritical CO2, ethanol, water, and their combinations) and temperatures (from 35 to 140 °C), high yields of polyphenols, flavonoids, alkaloids, and pigments were achieved. Key bioactive compounds extracted in significant quantities included caffeine (23.8 mass%), chlorophyll A (8.1 mg/g), chlorophyll B (0.7 mg/g), carotenoids (0.4 mg/g), epicatechin (7.7 mass%), catechin gallate (4.6 mass%), and epigallocatechin-3-gallate (30.2 mass%). The extract obtained in optimized processes demonstrated potent antioxidant activity (IC50 up to 88 μg/mL), strong antimicrobial activity (including methicillin-resistant Staphylococcus aureus- MRSA) with MIC up to 0.06 mg/mL, and selective anticancer activity against colon cancer cells. The presented findings provide a theoretical basis and technical guidance for enhancing the sustainable concentration of natural bioactive compounds, promoting their use in various industrial applications.

Ultrasound-assisted solvent extraction of phenolics, flavonoids, and major triterpenoids from Centella asiatica leaves: A comparative study

Centella asiatica has been known for its significant medicinal properties due to abundance of bioactive constituents like triterpenoids and flavonoids. Nevertheless, an appropriate solvent system and extraction technique is still lacking to ensure optimized extraction of bioactive constituents present in C. asiatica. Recently, scientists are more focused towards application of green sustainable extraction techniques for the valuable components from plant matrix owing to their eco-friendly and safe nature. Among these, ultrasonication (US) is known as a valuable strategy for separation of bioactive components from medicinal plants. Hence, current research was performed to observe the effect of ultrasonication in the presence of five different solvents (Water, Hexane, Methanol, Chloroform, and Ethyl acetate) on total phenolic contents (TPC), total flavonoid contents (TFC), antioxidant properties (DPPH, ABTS, Nitric oxide radical activity, and Superoxide anion assay), and four major triterpenoid contents in C. asiatica leaves. Herein, ultrasound assisted methanolic extract (UAME) possessed maximum amount of TPC (129.54 mg GAE/g), TFC (308.31 mg QE/g), and antioxidant properties (DPPH: 82.21 % & FRAP: 45.98 µmol TE/g) followed by ultrasound-assisted Water extract (UAWE), ultrasound-assisted ethyl acetate extract (UAEAE), ultrasound-assisted n-hexane extract (UAHE), and ultrasound-assisted chloroform extract (UACE), respectively. Moreover, the superoxide radical and nitric oxide assays depicted a similar trend, revealing the highest percent inhibition for UAME (SO: 83.47 % & NO: 66.76 %) however, the lowest inhibition was displayed by UACE (63.22 % & 50.21 %), respectively. Highest content of major terpenoids were found in UAME of C. asiatica leaves as madecassoside (8.21 mg/g) followed by asiaticoside (7.82 mg/g), madecassic acid (4.44 mg/g), and asiatic acid (3.38 mg/g). Ultrasound-assisted extraction technique can be an efficient extraction method for bioactive compounds present in C. asiatica. However, ultrasonication along with methanol as an extraction solvent can surely enhance the extraction of valuable constituents. The results of this study provide an insight into major terpenoids, and antioxidants present in extracts of C. asiatica, implicating its use in ancient medicine systems and future drug development.

Lipophilic EDTA-based ligands in different diluents for the extraction of rare earths: Preliminary results with Nd(III), Dy(III) and Pr(III) in chloride and nitrate media

A separation method for the recovery of neodymium(III) from two different media, chloride and nitrate, by implementing solvent extraction technique with a novel lipophilic diamide derivative of ethylenediamine tetraacetic acid (EDTA), namely 2,2’-N,N′-didecyl-dioxo-N,N′,N″,N″’-tetraazatetratriacontane-N″,N″’-diyl diacetic acid (H2E4C10), has been investigated. Initial screening results demonstrated acceptable solubility (ca. 15 mM) of the diamide in 1,3-diisopropylbenzene (DiPB) and in a 93:7 v:v n-dodecane:n-octanol mixture (DOm) as non-polar diluents. Further investigations aiming at determining operational parameters associated with the befitted extractant systems were conducted at pH ranging from 2 to 4 in chloride and nitrate media. A pH-dependent performance of the proposed systems revealed loading capacity peaking at pH = 3 with the respective values of 1.7 and 2.0 g L−1 in nitrate and chloride media. The extraction efficiency, the distribution coefficients, and the separation factor (E%,D and SF, respectively) were determined for an equimolar mixture of neodymium and two other potential competitive lanthanides, namely dysprosium and praseodymium. The best selectivity was observed in the chloride medium at pH = 4 yielding SFNd/Pr = 1.48 and SFNd/Dy = 2.03. Neodymium-to-extractant stoichiometry was evidenced in chloroform to be 1:1 H2E:Nd at pH = 2. Thermodynamic constants related to the considered extraction equilibrium have been determined by using the Van't Hoff relation and the slope analysis method. It appeared within the selected pH-range that the mechanism of the Nd3+ transfer was strongly influenced by the nature of the diluent. This was illustrated by the enthalpy-driven transfer when Nd3+ was extracted with the H2E-4C10-Dom system (aliphatic diluent) while the transfer became entropy-driven when the extraction was performed with the H2E-4C10-DiPB system (aromatic diluent). The complexation of Nd3+ involved mainly the participation of both the amide and carboxylic functional groups. The transfer of the cation to the organic phase might occur through the formation of the Nd(HE)A2 complex (where A is either a nitrate or a chloride anion), allowing for the lowest associated standard Gibbs free energy of transfer (−28 < ΔG° < −24 kJ mol−1) regardless of the aqueous feed.

Thermodynamic and kinetic study of palladium(II) complexation with 1-methyl-2-mercaptoimidazole (methimazole) and their importance for structural design of metallodrugs

The acidobasic and complexing properties of 1-methyl-2-mercaptoimidazole (Methimazole, an anti-thyroid drug) were investigated. The pKa 11.49 ± 0.03 was estimated by molecular absorption spectroscopy (I = 0.10 M NaCl, t = 25.0 ± 0.1 °C). This value is in good agreement with the value 11.58 ± 0.05, obtained using the solvent-extraction technique. Theoretical (LFER and quantum chemical calculations) and experimental (1H/13C NMR spectroscopy) methods confirmed that the ligand prefers to be in the thion form, and the proton dissociation takes place on the nitrogen atom. Using glass electrode potentiometry, the complexation of the Pd(II) ion by the methimazole ligand occurs without the participation of protons. The best chemical model considers the [Pd(HL)]2+, [Pd(HL)2]2+ and [Pd(HL)3]2+ complex species, whose stability constants were also determined using spectroscopy and capillary zone electrophoretic (CZE) measurements. The metal complexes dissociate at –log [H+] > 7, where an uncharged palladium(II) hydroxide is formed. The formation kinetics of the palladium(II) complex with methimazole were studied in perchloric and hydrochloric acids (I = 1.00 M, t = 15–40 °C) and the determined rate constants and activation parameters are consistent with literature values determined for the reactions of the Pd(II) ion with thiourea derivatives. The rate constants decrease by two orders of magnitude in both media, which can be assigned to a lower tendency of the chloride ion to dissociate from the [PdCl4]2− complex species than the water molecule from the [Pd(H2O)4]2+ ion. The presented results can be utilized for the design of new Pd and Pt metallodrugs.

Radiochemical separation of 161 Tb from neutron irradiated Gd target by liquid-liquid extraction technique

Abstract No-carrier-added (NCA) 161 Tb, which has advisable nuclear properties to be applied for cancer radiotherapy was produced at the Egyptian Second Research Reactor (ETRR-2) by neutron irradiation of natural gadolinium target via indirect nuclear reaction. The radiochemical separation of 161 Tb from irradiated gadolinium target was investigated based on solvent extraction technique using Cyanex 302. Several separation parameters were checked and optimized. According to the obtained results, the separation process of the investigated radioisotopes proceeds in two steps. The first step is an extraction of all of them into the organic phase in which the extraction % (98 %) was optimized at pH 4, 0.15 M of Cyanex 302 and 2.5 h extraction time. Moreover, the slope analysis method confirmed the participation of 2 mol of the organic extractant for the separation of 161 Tb from irradiated gadolinium. The second step is the separation of the 161 Tb isotope that was purified by the stripping of 159Gd with a citrate solution at pH 9, which is considered as a highly efficient and promising method for separation and purification of the two radioisotopes.

Native and TMT Chestnut Extractives as Hydrophobic and Photostabylizing Additives for Wood Surfaces

Wood extractives have proven strong anti-oxidative properties which may be used to mitigate surface deterioration caused by photolytic effects and free radical formations. An interesting challenge regarding wood extractives is understanding how they behave in terms of treating natural wood surfaces to reduce anti-oxidative processes that arise from exposure to the main environmental factors. In this study, the possible efficacy of chestnut (Castanea sativa Mill.) extractives derived from native (CH) and thermally modified wood (TMT CH), as a means of protecting against UV exposure in poplar (Populus spp.) and spruce (Picea abies Karst.) wood, was evaluated. Chestnut wood was first thermally modified at 180 °C for 3 h, and the extractives were obtained by the accelerated solvent extraction technique (ASE) and subsequently used to treat wood surfaces. Samples were immersed in extractive solutions and exposed to artificial UV-weathering exposure, then contact angle and colour stability were monitored during the process. An FTIR analysis of the photo-degradation process of poplar and spruce surfaces was also executed. Extractives of TMT chestnut changed the total colour variation in both poplar and spruce wood. A much darker colour compared to the extractives of native wood was observed and an increase in ∆E* from 9.75 to 30.76 and 6.24 to 22.97 in poplar and spruce was calculated. The stability of the colour depended both on the surface wood and the type of extractive. The initial contact angle remained almost unchanged in the poplar wood surface and only slightly increased in spruce regardless of whether they were treated with extractives from native or TMT chestnut wood. A strong reduction in contact angle after the accelerated UV exposure test was observed, especially in spruce treated with CH extractives. FTIR analysis confirmed the lower levels of chemical degradation of surfaces observed by colorimetry, where TMT CH extractives formed more stable chemical bonds than native extractives. The comparative analysis in this study clarified the complex relationships between the effects of high-temperature modification of wood and the potential protective role of TMT extractives on some wood surfaces.

Mass balance and economic study of a treatment chain for rare earths, base metals and precious metals recovery from used smartphones

In the present study, a comprehensive hydrometallurgical process was developed for the recovery of several types of metals from used cell phone printed circuit board assemblies. The overall process is divided into four stages of selective leaching of rare earth elements (REE), copper, nickel, silver and finally gold. After solubilization, the metals were purified using precipitation, solvent extraction, electrodeposition, and cementation techniques. Laboratory pilot-scale tests of the complete smart phone printed circuit board processing line showed REE, copper, nickel, silver, and gold recovery efficiencies of 78.0 %, 98.8 %, 81.8 %, 100 % and 96.1 %, respectively. The purity of the products obtained is evaluated at 94.8 % for rare earth oxides (70.0 % Nd2O3, 18.5 % Pr2O3, 2.8 % Dy2O3 and 2.4 % Sm2O3), 99.8 % for elemental copper, 94.3 % for nickel oxide, 93.8 % for silver and 89.3 % for gold. A scenario involving the installation of a plant processing 1 t/h of waste was evaluated using SuperPro Designer software. For a total investment of $53.22 million and an operating cost of $18.23 million per year, the main revenue is $65.77 million per year, with a return on investment of 91.6 % and a payback period of 1.1 years.

Heavy Naphtha Desulfurization by Ozone Generated via the DBD Plasma Reactor

This work presents an investigation into the ultra-desulfurization of heavy naphtha fuel (model using BT and DBT) using oxidation and solvent extraction techniques. Ozone produced by the DBD (Dielectric barrier discharge) plasma generator was employed in the oxidation process as an oxidant, and acetonitrile was used as a solvent extraction. Box-Behnken experimental design was adopted in the current study to examine oxidation desulfurization by non-thermal plasma for the various operation conditions including time, flow rate, and temperature on sulfur removal efficiency. Acetonitrile with an oxidized oil/solvent ratio of 1:1(v/v ratio) was utilized as the extraction solvent. The results showed that the maximum sulfur removal of about 91% was obtained with a temperature of 50°C, flow rate of 75 ml/min, and time of 4 hours.

Mechanically Interlocked Water-Soluble Pd6 Host for the Selective Separation of Coal Tar-Based Planar Aromatic Molecules.

Research on the synthesis of catenated cages has been a growing field of interest in the past few years. While multiple types of catenated cages with different structures have been synthesized, the application of such systems has been much less explored. Specifically, the use of catenated cages in the separation of industrially relevant molecules that are present in coal tar has not been explored before. Herein, we demonstrate the use of a newly synthesized interlocked cage 1 [C184H240N76O48Pd6] (M6L4), formed through the self-assembly of ligand L.HNO3 (tris(4-(1H-imidazole-1-yl)benzylidene)hydrazine-1-carbohydrazonhydrazide) with acceptor cis-[(tmchda)Pd(NO3)2] [tmchda = ±N,N,N',N'-tetramethylcyclohexane-1,2-diamine] (M). The interlocked cage 1 was able to separate the isomers (anthracene and phenanthrene) using a simple solvent extraction technique. Using the same technique, the much more difficult separation of structurally and physiochemically similar compounds acenaphthene and acenaphthylene was performed for the first time with 1 as the host. Other noninterlocked hexanuclear Pd6 cages having a wider cavity proved inefficient for such separation, demonstrating the uniqueness of the interlocked cage 1 for such challenging separation.

Liquid-liquid and solid-liquid extractions with low-temperature partitioning – A review

The paper represents the first review of solvent extraction techniques utilizing the low-temperature partitioning/purification (LTP) approach. Initially conceived in the 1960s to purify extracts from fatty matrices, it wasn't until the 2000s that this approach received increasing attention for its efficacy in extracting organic compounds from diverse samples, often without additional cleanup steps. This review covers a brief history and proposes a mechanism for LTP-based solvent extraction. Furthermore, the principal practical issues of the technique are spotlighted, elucidating the factors influencing extraction efficiency. The advantages, limitations, and potential combinations with other extraction techniques of the LTP-based solvent extractions are analyzed. The versatility of the LTP approach is demonstrated by its applications in extracting various compounds from food, environmental, and biological samples, emphasizing its potential for rapid sample preparation with minimal steps, few chemicals, and minimal analyst intervention.

Exploring the Tar Component Characteristics of Coalfield Fire Residual Coal Under Different Constant Temperature Oxidation

ABSTRACT Due to incomplete combustion of coal, a large amount of tar will be produced in coal fire area, which will cause serious pollution to the environment. In this paper, we dissolve the tar components in the residual coal by solvent extraction technique, analyze the organic components in the residual coal tar at different temperatures by GC-MS, study the characteristics of the residual coal tar components at different temperatures, and analyze the influence of the residual coal tar on the combustion and rekindling characteristics of the fire zone of the coalfield. The results show that: the components of coal combustion residual tar are mainly alkane organics which are easy to be oxidized and volatilized, and the content is more than 55%. At 300°C, the color of residual tar extract is light yellow or yellowish brown, and becomes colorless with the increase of temperature. At 300–500°C, the lower the temperature in the fire zone, the more residual tar in the coal, and the greater the risk of reignition in the extinguishing fire zone. The types of organic compounds in the tar residue from combustion have obvious characteristics at different temperature stages. Organic species have obvious characteristics at different temperature stages. By identifying the temperature stage of the coalfield fire area development, the organic structure characteristics and change trend of the residual coal tar can be deduced, and mastering the organic structure characteristics of the residual tar in the coalfield fire area can also reflect the temperature stage of coal fire area to a certain extent.

Seasonal Variation of Groundwater Quality in Bonny Island, Rivers State Nigeria

This study investigated the seasonal variations in physicochemical parameters, heavy metals, and petroleum hydrocarbons in groundwater samples collected in nine locations in Bonny Island, Rivers State Nigeria. The water samples for the dry season were collected in December and January while for the wet season, water samples were collected in July and October. A quantitative approach was employed, involving the collection of quantitative data through field sampling and laboratory analysis. Physicochemical parameters, including pH, electrical conductivity, dissolved oxygen, and nutrient levels, were measured using standard analytical techniques. Heavy metal concentrations (Fe, Cd, etc.) were determined using atomic absorption spectrophotometry, while petroleum hydrocarbons (total hydrocarbons and polycyclic aromatic hydrocarbons) were analyzed through solvent extraction and gas chromatography techniques. The study revealed significant seasonal variations in several parameters, with notable significant decreases in phosphate during the wet season and significant increases in chromium and cadmium levels during the dry season (p-value &lt; 0.05). Petroleum hydrocarbon concentrations also exhibited seasonal fluctuations, potentially influenced by precipitation patterns, oil and gas activities, and accidental spills or leaks which were observed during the dry season.

Optimizing Process Parameters for Controlled Drug Delivery: A Quality by Design (QbD) Approach in Naltrexone Microspheres.

The formulation of microspheres involves a complex manufacturing process with multiple steps. Identifying the appropriate process parameters to achieve the desired quality attributes poses a significant challenge. This study aims to optimize the critical process parameters (CPPs) involved in the preparation of naltrexone microspheres using a Quality by Design (QbD) methodology. Additionally, the research aims to assess the drug release profiles of these microspheres under both in vivo and in vitro conditions. Critical process parameters (CPPs) and critical quality attributes (CQAs) were identified, and a Box-Behnken design was utilized to delineate the design space, ensuring alignment with the desired Quality Target Product Profile (QTPP). The investigated CPPs comprised polymer concentration, aqueous phase ratio to organic phase ratio, and quench volume. The microspheres were fabricated using the oil-in-water emulsion solvent extraction technique. Analysis revealed that increased polymer concentration was correlated with decreased particle size, reduced quench volume resulted in decreased burst release, and a heightened aqueous phase ratio to organic phase ratio improved drug entrapment. Upon analyzing the results, an optimal formulation was determined. In conclusion, the study conducted in vivo drug release testing on both the commercially available innovator product and the optimized test product utilizing an animal model. The integration of in vitro dissolution data with in vivo assessments presents a holistic understanding of drug release dynamics. The QbD approach-based optimization of CPPs furnishes informed guidance for the development of generic pharmaceutical formulations.

Removal of Co(II) and various metal ions from the residue of the zinc plant through solvent extraction using both acid and neutral extractants

AbstractThe recovery of cobalt from secondary sources is a crucial issue in technology development, particularly for its numerous applications in various industries. Solvent extraction has proven an effective method for metallic ions separation from secondary sources. The main goal of this work was to study the separation of metals by solvent extraction technique from zinc plant leach waste. Initially, several extractants, including Cyanex 272, Cyanex 301, LIX 5640 H, Alamine 336, and tri‐n‐octylamine (TOA), were tested to treat the leach solution. It was discovered that the saponified extractant di‐(2‐ethylhexyl) phosphoric acid (D2EHPA) (10%) + tri‐n‐butyl phosphate (TBP) (10%) effectively eliminated interfering elements such as manganese, zinc, and iron, with extraction efficiencies of 95%, 98%, and 99.9%, respectively. To increase the concentration of cobalt in the purified solution, the cobalt recovery step was performed using various acids on the loaded organic phase. The best outcome was achieved using ammonium sulphate salt (1 M), which recovered about 50% of the cobalt present in the organic phase. The recovered cobalt was then subjected to the electrowinning process to produce cobalt metal of high purity. A cathodic current density of 100 A/m2 was determined to be the optimal current for the electrolyte solution. Lastly, scanning electron microscope (SEM) and X‐ray fluorescence (XRF) analyses were carried out to examine the structure and purity of the resulting metallic cobalt, which was found to have a purity of 99.5%.

Antioxidant and Anti-inflammatory Potential of Sargassum sp Extract in Lotion Preparations

Sargassum sp. is a type of brown algae found in Indonesian marine waters with great potential in the food and pharmaceutical industries. There is antioxidant and anti-inflammatory potential in Sargassum sp. extract so that it makes this type utilised as a lotion preparation. It is necessary to know the potential of Sargassum sp. extract in making lotions. This research uses extraction method to produce Sargassum sp. extract with organic solvent extraction technique, namely alcohol. In addition, the emulsion method was used in the manufacture of lotion preparations. Furthermore, secondary metabolites and anti-inflammatory (irritation) tests were conducted. In addition, the lotion preparation can be evaluated by conducting organoleptic, pH, and homogeneity tests. The results showed that the Sargassum sp. extract contained significant antioxidant compounds, as indicated by a decrease in DPPH absorbance. Sargassum extract contains alkaloid, flavonoid, saponin, and tannin. In addition, lotion preparations containing Sargassum sp. extract also showed a significant decrease in pro-inflammatory cytokine expression in skin cells exposed to UVB radiation. In addition, the irritation test showed negative results with a safety level without causing irritation to the skin. These findings indicate the potential of Sargassum sp. extract in producing lotion preparations with antioxidant and anti-inflammatory effects that can contribute to skin protection from oxidative damage and inflammation.

Extraction of metal values from iron-rich mine tailings via chloridized roasting and water leaching

The surge in mining and mineral processing to meet metal demand has led to accumulation of mining by-products like tailings, waste rocks, and acid mine drainage, containing high iron, copper, nickel, and zinc concentrations. These residues pose environmental threats. The concept of technospheric mining aims to repurpose these wastes for beneficial uses, reducing disposal and ecological impact while benefiting stakeholders. Within this context, the present investigation focuses on the discriminative retrieval of copper and nickel from mine tailings characterized by elevated iron content. This is achieved through formulation of an energy-efficient technique designed to surmount the challenge of iron co-extraction during hydrometallurgical processes aimed at extracting and recuperating metal values from intricate phases. The proposed method entails the amalgamation of mine tailings and solid NH4Cl in a stoichiometric ratio of 1:2, followed by roasting at 300 °C for a span of 1 h. Application of chloridized roasting orchestrates the transformation of copper and nickel into soluble metal chlorides, while concurrently inducing conversion of iron into a stable iron oxide state. Subsequent stages encompass the separation of copper and nickel from the water leach liquor, achieved through solvent extraction techniques utilizing LIX84I and Cyanex 272 as extractants. Rigorous characterization efforts, employing techniques such as X-ray Diffraction (XRD) and Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS), are undertaken to elucidate the attributes of the raw material and solid residues. Remarkably, the comprehensive isolation of copper, nickel, and iron is realized without generation of any effluents, ensuring preservation of environmental equilibrium.

Key phytochemicals contributing to the bitterness of quinoa

Despite its nutritional components and potential health benefits, the bitterness of quinoa seed limits its utilization in the food industry. Saponins are believed to be the main cause of the bitterness, but it is still uncertain which specific compound is responsible. This study aimed to isolate the main components contributing to the bitterness in quinoa seed by solvent extraction and various column chromatography techniques guided by sensory evaluation. Five compounds were identified by mass spectrometry and nuclear magnetic resonance analyses, with the dose-over-threshold factors from 29.03 to 198.89. The results confirmed that triterpenoids are responsible for the bitter taste in quinoa seed, with phytolaccagenic acid derivatives being the primary contributor. Additionally, kaempferol 3-O-(2″, 6″-di-O-α-rhamnopyranosyl)-β-galactopyranoside (namely mauritianin), was demonstrated for the first time to be associated with the bitterness of quinoa. This study could provide new insight into the bitter compound identification in quinoa.

Quantitative comparison and evaluation between aerial and underground parts of Gentiana straminea through simultaneous determination of five major compounds by RP-HPLC

Herbal Gentiana straminea Maxim. (Family Gentianaceae), “Ma Hua Jiao” in Chinese, is a commonly used Chinese medicine. Secoiridoids and flavonoids have been identified as the major active components of herbal medicines used in the treatment of hepatitis, rheumatism and many other diseases. It is the overharvesting of the roots of this plant for medicinal purposes that has led to a drastic decline in its population. In the present study, the above and below ground parts of Gentian Bitter Glycine were quantitatively compared and evaluated for the determination of the major active constituents. Five major compounds, loganic acid, swertiamarin, gentiopicroside, sweorside and isoorientin, were extracted by solvent extraction technique and analyzed by Reversed-phase High Performance Liquid Chromatography (RP-HPLC). By analysing the principal components and calculating the composite scores, the results show that the aboveground component in different areas ranked higher compared to the underground component, with the former being able to substitute to some extent for the latter's underground component. Finally, based on hierarchical cluster analysis, we identified the ideal natural growing region for aerial parts of G. straminea distributed on the Qinghai-Tibetan Plateau. The significance of this work is that we can balance the demand for herbs with environmental preservation by selectively picking the aerial parts, which can regrow next year, instead of removing the whole plant. It protects the fragile ecological environment of the Tibetan Plateau and is important for sustainable development.

Process Optimization Using Box‐Behnken Design for the Solvent Extraction and Separation of Iron, Cobalt, and Nickel from Simulated Crud Solution

AbstractThe corrosion product deposit (crud) found on the surface of the fuel rod of the pressurized water reactors (PWRs) chiefly made up of nickel ferrite. Fe, Co, Ni and Cr are the major elements exist in PWR crud. Ascribable to the simplicity in execution, handling, and option for recyclability, solvent extraction technique has been broadly used in nuclear energy sector. In the present investigation, the recovery of iron, cobalt, and nickel has been studied from simulated crud solution in nitrate medium using a novel hydrophobic menthol‐decanoic acid‐based deep eutectic solvent. Process parameters such as pH, DES concentration and shaking time were considered as input variables, and concentration of Fe, Co, and Ni as response variables for the design of experiments. Response surface methodology via Box‐Behnken design using polynomial quadratic model was selected for optimization of solvent extraction experiments. A total of 17 runs were conducted and the results were used for optimization purpose. Complete separation of Co/Fe and Co/Ni is achievable under various extraction conditions. As per the BBD analysis, the optimization conditions obtained were pH=1.9, [DES]=2.99 mol/L and shaking duration=18.27 min. Under these conditions,the amount of Fe, Co and Ni extracted were found as 32.29 g/L, 0.2111 g/L, and 19.83 g/L, respectively.