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Volume 9
Issue 12
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Separations, Volume 9, Issue 12 (December 2022) – 67 articles

Cover Story (view full-size image): Metribuzin is a pre- and post-emergence triazinone herbicide used to control annual grass and broad-leaved weeds in a variety of crops. The evaluation of this chemical on environmental and human health concluded that this pesticide has toxicity even at low doses. In environmental conditions, metribuzin degrades into three main metabolites: diketo-metribuzin, desamino-metribuzin, and desamino-diketo-metribuzin. These have high water solubility and soil mobility, so crop uptake is expected. Different methods have been reported for the determination of metribuzin but are scarce for its metabolites, particularly via gas chromatography. This study develops a fast and sensitive method for the analysis of metribuzin and three metabolites in soil and plants by UAE and GC-MS/MS that will allow monitoring their presence in food and the environment. View this paper
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21 pages, 6019 KiB  
Article
A Novel Method for Simulating Micro-Scale Water Droplet Movements
by Zhijie Lin, Zhongtian Hu, Senyu Lou, Lingling Guo and Jingjing Chen
Separations 2022, 9(12), 451; https://doi.org/10.3390/separations9120451 - 19 Dec 2022
Viewed by 1878
Abstract
Micro-scale fluids are tiny droplets that adhere to the surface of an object as a result of rainfall, perspiration, etc. Micro-scale fluid simulation is widely used in fields such as film and games. The existing state-of-the-art simulation methods are not suitable for simulating [...] Read more.
Micro-scale fluids are tiny droplets that adhere to the surface of an object as a result of rainfall, perspiration, etc. Micro-scale fluid simulation is widely used in fields such as film and games. The existing state-of-the-art simulation methods are not suitable for simulating water droplets moving on a surface due to the fact that the water droplets cannot leave the texture space and their movements always depend on the continuous UV region. In this study, a novel method for simulating water droplets moving on a surface is proposed. We divide the droplets into two types: (1) two-dimensional droplets and (2) three-dimensional droplets and we implement the transformation between two-dimensional droplets in the texture space and three-dimensional droplets in the physical space. In the preprocessing phase, jump textures, coordinate transform textures and force field textures are generated in the non-continuous UV regions on a 3D object’s surface. In the process of simulation, water droplets are treated as rigid particles. The Velocity-Verlet-based method is adopted to solve the motion trajectory equation, and the boundary droplet transport algorithm is implemented based on jump texture. In the process of rendering, the height map is generated according to the simulation in the texture space and then the liquid bridge phenomenon between the droplets is simulated based on the Gaussian blur and the color rank algorithm. Finally, they are converted into normal texture-rendering droplets. The experimental result shows that the proposed method works well when simulating the movements of water droplets on a surface in a real-time manner, and it makes the movement simulation of dimension-reducing water droplets no longer depend on the continuous surface and continuous UV region. Moreover, the simulation efficiency of the proposed method is two times higher than that of the Smoothed Particle Hydrodynamics (SPH) method. Full article
(This article belongs to the Special Issue Advances in Separation Engineering)
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13 pages, 2620 KiB  
Article
Effect of Alkali Cation on Performance of Alkali-Activated Slag Mortar in Cold Environments
by Cheng Ju, Rongrong Ye, Yunfei Wu, Pengfei Sun, Yushi Liu and Yingzi Yang
Separations 2022, 9(12), 450; https://doi.org/10.3390/separations9120450 - 19 Dec 2022
Cited by 2 | Viewed by 1655
Abstract
Alkali-activated slag (AAS) is a promising cementing material for winter construction due to its continuous hydration at sub-zero temperature. In order to obtain a higher mechanical strength of AAS mortar in winter construction, the most efficient alkali activator should be selected. Potassium silicate [...] Read more.
Alkali-activated slag (AAS) is a promising cementing material for winter construction due to its continuous hydration at sub-zero temperature. In order to obtain a higher mechanical strength of AAS mortar in winter construction, the most efficient alkali activator should be selected. Potassium silicate and sodium silicate as alkaline activators of AAS mortar possess a high strength and hydration rate at ordinary temperature. Potassium silicate and sodium silicate as alkali activators showed different properties because of different alkali cations, so the effect of alkali cation on the performance of AAS mortar was studied at sub-zero temperature. The mechanical properties of potassium-silicate-activated AAS (K-AAS) mortar and sodium-silicate-activated AAS (N-AAS) mortar were thoroughly compared at the ambient temperatures of −10 °C, 0 °C, and 20 °C. The compressive and flexural strength of K-AAS mortar was increased by 130.4% and 72.3% at the age of 1 day and increased by 49% and 33.7% at the age of 28 days at the ambient temperature of −10 °C compared with N-AAS mortar. In order to reveal the mechanism behind the influence of different alkali cations on the mechanical properties of AAS mortar, the hydration heat, hydration products, and pore structures of AAS were characterized. The hydration heat exhibited that the rate of heat release and the cumulative heat release of K-AAS are higher than N-AAS, indicating the higher reaction degree of K-AAS. DTG/TG and ATR-FTIR spectra showed that K-AAS generated more gel product C(-A)-S-H compared with N-AAS at the same curing temperature. The MIP results exhibited that the porosity of K-AAS was lower than N-AAS. Finally, the mechanism explanation of the effect of alkali cation on the performance of AAS mortar was proposed. To sum up, potassium silicate should be selected as an alkali activator of AAS in winter construction. Full article
(This article belongs to the Section Environmental Separations)
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16 pages, 6957 KiB  
Article
High Value-Added Utilization of Waste Hydrodesulfurization Catalysts: Low-Cost Synthesis of Cathode Materials for Lithium-Ion Batteries
by Junbo Zhou, Lang Qiu, Yao Li, Yuting Deng, Qing Zhao, Yang Hu, Fuqiren Guo, Chaoqiong Zhu, Benhe Zhong, Yang Song and Xiaodong Guo
Separations 2022, 9(12), 449; https://doi.org/10.3390/separations9120449 - 19 Dec 2022
Cited by 2 | Viewed by 2179
Abstract
This work introduces a one-step method for the preparation of layered oxide cathode materials utilizing pure Ni and Co mixed solution obtained from the waste hydrodesulfurization (HDS) catalyst. An efficient non-separation strategy with pyrometallurgical-hydrometallurgical (pyro-hydrometallurgical) process consisting of roasting and leaching is proposed. [...] Read more.
This work introduces a one-step method for the preparation of layered oxide cathode materials utilizing pure Ni and Co mixed solution obtained from the waste hydrodesulfurization (HDS) catalyst. An efficient non-separation strategy with pyrometallurgical-hydrometallurgical (pyro-hydrometallurgical) process consisting of roasting and leaching is proposed. Most of the impurity metal elements such as Mo and V were removed by simple water leaching after the waste HDS catalyst was roasted with Na2CO3 at 650 °C for 2.5 h. Additionally, 93.9% Ni and 100.0% Co were recovered by H2SO4 leaching at 90 °C for 2.5 h. Then, LiNi0.533Co0.193Mn0.260V0.003Fe0.007Al0.004O2 (C–NCM) was successfully synthesized by hydroxide co-precipitation and high temperature solid phase methods using the above Ni and Co mixed solution. The final C–NCM material exhibits excellent electrochemical performance with a discharge specific capacity of 199.1 mAh g−1 at 0.1 C and a cycle retention rate of 79.7% after 200 cycles at 1 C. This novel process for the synthesis of cathode material can significantly improve production efficiency and realize the high added-value utilization of metal resources in a waste catalyst. Full article
(This article belongs to the Special Issue Efficient and Green Recovery of Metal Minerals)
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35 pages, 3943 KiB  
Review
Metabolites of Serratula L. and Klasea Cass. (Asteraceae): Diversity, Separation Methods, and Bioactivity
by Daniil N. Olennikov
Separations 2022, 9(12), 448; https://doi.org/10.3390/separations9120448 - 16 Dec 2022
Cited by 4 | Viewed by 2190
Abstract
Serratula L. and Klasea Cass. are two systematically related genera of the family Asteraceae, which are distributed in most of the Eurasia area and are used as food and colorants and in traditional medicines as a drug. Since 1967, 261 metabolites have been [...] Read more.
Serratula L. and Klasea Cass. are two systematically related genera of the family Asteraceae, which are distributed in most of the Eurasia area and are used as food and colorants and in traditional medicines as a drug. Since 1967, 261 metabolites have been isolated and identified from five Serratula species and 21 Klasea species. This review provides information on the chemodiversity of the terpenes, penolics, lipids, and other compounds found in both genera and their occurrence in individual species. Among the studied species, the most studied are S. coronata subsp. coronata, K. centauroides, and K. centauroides subsp. centauroides. This review also provides information on the methods of extraction, isolation, and analysis of ecdysteroids and flavonoids as the most valuable metabolites. For the first time, we provide general information about the biological activity of these extracts and individual compounds. The data presented in this review demonstrate the prospects of Serratula and Klasea species as sources of bioactive metabolites. Full article
(This article belongs to the Special Issue Feature Papers in Separations from Editorial Board Members)
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18 pages, 3258 KiB  
Article
Phytochemical, Antimicrobial, Antioxidant, and In Vitro Cytotoxicity Evaluation of Echinops erinaceus Kit Tan
by Sherouk Hussein Sweilam, Fatma M. Abdel Bar, Ahmed I. Foudah, Mohammed H. Alqarni, Nouran A. Elattal, Omayma D. El-Gindi, Moshera M. El-Sherei and Essam Abdel-Sattar
Separations 2022, 9(12), 447; https://doi.org/10.3390/separations9120447 - 16 Dec 2022
Cited by 10 | Viewed by 2599
Abstract
Wild plants are used by many cultures for the treatment of diverse ailments. However, they are formed from mixtures of many wanted and unwanted phytochemicals. Thus, there is a necessity to separate the bioactive compounds responsible for their biological activity. In this study, [...] Read more.
Wild plants are used by many cultures for the treatment of diverse ailments. However, they are formed from mixtures of many wanted and unwanted phytochemicals. Thus, there is a necessity to separate the bioactive compounds responsible for their biological activity. In this study, the chemical composition as well as antimicrobial and cytotoxic activities of Echinops erinaceus Kit Tan (Asteraceae) were investigated. This led to the isolation and identification of seven compounds, two of which are new (erinaceosin C3 and erinaceol C5), in addition to methyl oleate (C1) and ethyl oleate (C2), loliolide (C4), (E)-p-coumaric acid (C6), and 5,7,3`,5`-tetrahydroxy flavanone (C7). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HR-ESI-MS. The methanol extract showed the highest antimicrobial activity among the tested extracts and fractions. The n-hexane and EtOAc extracts showed remarkable antimicrobial activity against B. subtilus, P. aeruginosa, E. coli, and C. albicans. A cytotoxicity-guided fractionation of the most bioactive chloroform extract resulted in the isolation of bioactive compounds C1/C2, which showed significant cytotoxicity against HCT-116 and CACO2 cell lines (IC50 24.95 and 19.74 µg/mL, respectively), followed by compounds C3 (IC50 82.82 and 76.70 µg/mL) and C5 (IC50 99.09 and 87.27 µg/mL), respectively. The antioxidant activity of the bioactive chloroform fractions was screened. Molecular docking was used to explain the results of the antimicrobial and anticancer activities against five protein targets, including DNA gyrase topoisomerase II, enoyl-acyl carrier protein reductase of S. aureus (FabI), dihydrofolate reductase (DHFR), β-catenin, and human P-glycoprotein (P-gp). Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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15 pages, 2475 KiB  
Article
Purification of Two Taxanes from Taxus cuspidata by Preparative High-Performance Liquid Chromatography
by Yajing Zhang, Zirui Zhao, Wenlong Li, Yuanhu Tang, Huiwen Meng and Shujie Wang
Separations 2022, 9(12), 446; https://doi.org/10.3390/separations9120446 - 16 Dec 2022
Cited by 3 | Viewed by 2091
Abstract
In the present study, an effective method of preparative high-performance liquid chromatography (Prep-HPLC) was established to purify two taxanes in Taxus cuspidata. During the experimental operation, the effects of flow rate, injection volume, and column temperature on the purity of 10-deacetyltaxol (10-DAT) [...] Read more.
In the present study, an effective method of preparative high-performance liquid chromatography (Prep-HPLC) was established to purify two taxanes in Taxus cuspidata. During the experimental operation, the effects of flow rate, injection volume, and column temperature on the purity of 10-deacetyltaxol (10-DAT) and paclitaxel (PTX) were investigated, and the optimized conditions were as follows: flow rate of 10 mL/min, injection volume of 0.5 mL, and column temperature of 30 °C. Under these conditions, the purity of 10-DAT and PTX reached 95.33% and 99.15%, respectively. The purified products were characterized by scanning electron microscopy (SEM), high-performance liquid chromatography (HPLC), and electrospray ionization-high resolution mass spectrometry (ESI-HRMS). The results demonstrated that preparative HPLC can effectively purify 10-DAT and PTX from Taxus cuspidata with a purity of >95%, which was suitable for the large-scale preparation of 10-DAT and PTX. Full article
(This article belongs to the Special Issue Chromatography-Mass Spectrometry Technology Research)
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9 pages, 2647 KiB  
Article
Efficient Production of Antioxidants from Rape Pollen via a Chromatographic Strategy
by Liugen Jin, Haiqing Liu, Xueliang Liu, Ke Gu, Minchen Wu and Jianfeng Huang
Separations 2022, 9(12), 445; https://doi.org/10.3390/separations9120445 - 15 Dec 2022
Viewed by 1778
Abstract
Rape pollen has always been considered as a research hotspot in health foods and pharmaceuticals due to its abundance of natural active ingredients. In this work, a compound with antioxidant activity was directly isolated from the methanol extract of rape pollen using a [...] Read more.
Rape pollen has always been considered as a research hotspot in health foods and pharmaceuticals due to its abundance of natural active ingredients. In this work, a compound with antioxidant activity was directly isolated from the methanol extract of rape pollen using a two-step procedure, under the supervision of online HPLC−1,1-diphenyl-2-picrylhydrazyl (HPLC-DPPH) detection. Firstly, online HPLC−DPPH detection was used to identify the active peaks in the methanol extract of rape pollen, and then the methanol extract was pretreated via medium-pressure liquid chromatography (MPLC) to obtain the target fraction 3 (Fr3). Fr3 was further purified using HPLC to finally obtain the target fraction 3-1, which was identified as kaempferol 3,4′-di-O-β-D-glucopyranoside through NMR and mass spectrometry. To further explore the free radical scavenging activity of this compound, its DPPH scavenging ability was determined, and two proteins related to the antioxidant pathway were used for molecular docking. The results revealed that the chromatographic strategy used in this study was efficient and reliable in separating high−purity antioxidants from rape pollen. A strategy such as this, meanwhile, also holds promise for qualitatively identifying and specifically isolating active compounds from other natural products. Full article
(This article belongs to the Topic Discovery of Bioactive Compounds from Natural Organisms and Their Molecular Mechanisms against Diseases)
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17 pages, 1385 KiB  
Review
Application of O3/PMS Advanced Oxidation Technology in the Treatment of Organic Pollutants in Highly Concentrated Organic Wastewater: A Review
by Bojiao Yan, Qingpo Li, Xinglin Chen, Huan Deng, Weihao Feng and Hai Lu
Separations 2022, 9(12), 444; https://doi.org/10.3390/separations9120444 - 15 Dec 2022
Cited by 2 | Viewed by 2203
Abstract
The ozone/peroxymonosulfate (O3/PMS) system has attracted widespread attention from researchers owing to its ability to produce hydroxyl radicals (•OH) and sulfate radicals (SO4•−) simultaneously. The existing research has shown that the O3/PMS system significantly degrades refinery [...] Read more.
The ozone/peroxymonosulfate (O3/PMS) system has attracted widespread attention from researchers owing to its ability to produce hydroxyl radicals (•OH) and sulfate radicals (SO4•−) simultaneously. The existing research has shown that the O3/PMS system significantly degrades refinery trace organic compounds (TrOCs) in highly concentrated organic wastewater. However, there is still a lack of systematic understanding of the O3/PMS system, which has created a significant loophole in its application in the treatment of highly concentrated organic wastewater. Hence, this paper reviewed the specific degradation effect, toxicity change, reaction mechanism, various influencing factors and the cause of oxidation byproducts (OBPs) of various TrOCs when the O3/PMS system is applied to the degradation of highly concentrated organic wastewater. In addition, the effects of different reaction conditions on the O3/PMS system were comprehensively evaluated. Furthermore, given the limited understanding of the O3/PMS system in the degradation of TrOCs and the formation of OBPs, an outlook on potential future research was presented. Finally, this paper comprehensively evaluated the degradation of TrOCs in highly concentrated organic wastewater by the O3/PMS system, filling the gaps in scale research, operation cost, sustainability and overall feasibility. Full article
(This article belongs to the Special Issue Separation Processes for Effective Removal of Emerging Contaminants from Water and Wastewater)
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14 pages, 2219 KiB  
Article
Comparative Characterization of Grain Protein Content and Composition by Chromatography-Based Separation Methods (SE-HPLC and RP-HPLC) of Ten Wheat Varieties Grown in Different Agro-Ecological Zones of Algeria
by Nesrine Hacini, Radia Djelloul, Ahmed Hadef, Marie-Françoise Samson and Dominique Desclaux
Separations 2022, 9(12), 443; https://doi.org/10.3390/separations9120443 - 15 Dec 2022
Cited by 4 | Viewed by 2692
Abstract
To characterize and compare the protein quality of ten durum wheat genotypes grown under three cropping modalities in Algeria (subhumid in Algiers, subhumid-semiarid in Constantine, and semiarid in Sétif), the protein profile of their kernels was performed by High-Performance Liquid Chromatography (SE-HPLC and [...] Read more.
To characterize and compare the protein quality of ten durum wheat genotypes grown under three cropping modalities in Algeria (subhumid in Algiers, subhumid-semiarid in Constantine, and semiarid in Sétif), the protein profile of their kernels was performed by High-Performance Liquid Chromatography (SE-HPLC and RP-HPLC). The “variety” factor has a major impact, mainly on the insoluble fraction (Fi), on the gliadin/glutenin ratio, on the large and small glutenin aggregates (F1 and F2, respectively), and on ω-gliadins and high molecular weight albumins (F3). Conversely, the total protein content and the albumin-globulin fraction (F5) depend mainly on the environment. The α- β- and γ-gliadins (F4) are equally dependent on variety and environment. The subhumid-semiarid agroecological conditions of Constantine (SH-SA) favored an important accumulation of proteins (14.1%), particularly by an increased synthesis of omega gliadins and high-molecular-weight glutenin subunits (HMW-GS), compared to those of Algiers (SH) and Sétif (SA). For these latter environments, metabolic-type proteins are predominant, reflected in a higher F5 fraction (p < 0.05) (albumin and globulin), and significantly more alpha-beta and gamma gliadins. The use of chromatographic analyses to characterize wheat genotypes remains a reliable tool for breeding and variety promotion programs and can provide a better understanding of the ecophysiology of cereal crops. Full article
(This article belongs to the Special Issue Spectroscopic, Chromatographic, and Chemometric Techniques Applied in Food Products Characterization)
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10 pages, 1065 KiB  
Article
Testing Thymol-Based DES for the Elimination of 11 Textile Dyes from Water
by Lorena Villar, Óscar Martínez-Rico, Andrés Asla, Ángeles Domínguez and Begoña González
Separations 2022, 9(12), 442; https://doi.org/10.3390/separations9120442 - 15 Dec 2022
Cited by 8 | Viewed by 2237
Abstract
Textile industries release dangerous wastewater that contain dyes into the environment. Due to their toxic, carcinogenic and mutagenic nature, they must be removed before the discharge. Liquid–liquid extraction has proven to be an efficient method for the removal of these dyes. As extractants, [...] Read more.
Textile industries release dangerous wastewater that contain dyes into the environment. Due to their toxic, carcinogenic and mutagenic nature, they must be removed before the discharge. Liquid–liquid extraction has proven to be an efficient method for the removal of these dyes. As extractants, deep eutectic solvents (DESs) have shown excellent results in recent years, as well as presenting several green properties. Therefore, four different hydrophobic DESs based on natural components were prepared thymol:decanoic acid (T:D (1:1)), thymol:DL-menthol (T:M (1:1)), thymol:DL-menthol (T:M (1:2)) and thymol:coumarin (T:C (2:1)) for the extraction of Malachite Green (MG), Brilliant Blue G (BBG), Acid Yellow 73 (AY73), Reactive Red 29 (RR29), Acid Blue 113 (AB113), Reactive Black 5 (RB5), Remazol Brilliant Blue (RBB), Direct Yellow 27 (DY27), Acid Blue 80 (AB80), Direct Blue 15 (DB15) and Acid Violet 43 (AV43) dyes from water. The operational parameters of the liquid–liquid extraction were selected in order to save time and materials, resulting in 30 min of stirring, 15 min of centrifugation and an aqueous:organic ratio of 5:1. In these conditions, the highest values of extraction obtained were 99% for MG, 89% for BBG and 94% for AY73. Based on these results, the influence of the aqueous:organic phase ratio and the number of necessary stages to achieve water decolorization was studied. Full article
(This article belongs to the Special Issue Removal of Emerging Pollutants and Environmental Analysis)
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12 pages, 3747 KiB  
Article
Solid Phase Extraction of (+)-Catechin from Cocoa Shell Waste Using Dual Ionic Liquid@ZIF8 Covered Silica
by Xiaoman Li, Ruobing Qiao, Xuyang Jiu and Minglei Tian
Separations 2022, 9(12), 441; https://doi.org/10.3390/separations9120441 - 15 Dec 2022
Cited by 1 | Viewed by 1574
Abstract
(+)-catechin is one category of flavonoids in cocoa shell waste and it has been reported to have many health benefits. In order to isolate it from aqueous extracted solution of cocoa shell waste by solid phase extraction (SPE), a series of dual ionic [...] Read more.
(+)-catechin is one category of flavonoids in cocoa shell waste and it has been reported to have many health benefits. In order to isolate it from aqueous extracted solution of cocoa shell waste by solid phase extraction (SPE), a series of dual ionic liquids@ZIF8-covered silica were prepared as the sorbents. Regarding the operation conditions of SPE and the characteristic structure of (+)-catechin, ZIF8-covered silica was synthesized to establish a stable and porous substrate, and various dual ionic liquids with multiple properties were immobilized on substrate to obtain a high adsorption capacity. Different adsorption conditions were investigated and the highest adsorption capacity (58.0 mg/g) was obtained on Sil@ZIF8@EIM-EIM at 30 °C during 60.0 min. When the sorbent was applied in the SPE process, 96.0% of the total amount of (+)-catechin from cocoa shell waste can be isolated after several washing and elution steps. The satisfactory recoveries of 97.5–100.2% and RSDs of 1.3–3.2% revealed that the SPE process was accurate and precise. The stability of Sil@ZIF8@EIM-EIM was tested in water and the reusability was tested using repeated adsorption/desorption process. The results revealed that Sil@ZIF8@EIM-EIM as an efficient sorbent can isolate (+)-catechin from cocoa shell waste. Full article
(This article belongs to the Special Issue Application of Ionic Liquids in Separation Science)
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13 pages, 3362 KiB  
Article
Simple and Sensitive Analysis of Clenbuterol in Urine Matrices by UHPLC-MS/MS Method with Online-SPE Sample Preparation
by Kristián Slíž, Dominika Olešová, Juraj Piešťanský and Peter Mikuš
Separations 2022, 9(12), 440; https://doi.org/10.3390/separations9120440 - 14 Dec 2022
Cited by 4 | Viewed by 2557
Abstract
Clenbuterol is one of the most misused anabolic agents in professional sports. Therefore, the monitoring of clenbuterol in body fluids such as human urine is related to the development of rapid, selective and sensitive analytical methods that produce reliable results. In this work, [...] Read more.
Clenbuterol is one of the most misused anabolic agents in professional sports. Therefore, the monitoring of clenbuterol in body fluids such as human urine is related to the development of rapid, selective and sensitive analytical methods that produce reliable results. In this work, these requirements were met by a two-dimensional separation method based on online solid-phase extraction coupled with ultra-high performance liquid chromatography–tandem mass spectrometry (SPE–UHPLC–MS/MS). The developed method provides favorable performance parameters, and it is characterized by minimum manual steps (only dilution and the addition of an internal standard) in the sample preparation. A limit of quantification (LOQ) of 0.1 ng/mL, excellent linearity (0.9999), remarkable precision (1.26% to 8.99%) and high accuracy (93.1% to 98.7%) were achieved. From a practical point of view, the analytical performance of the validated SPE–UHPLC–MS/MS method was demonstrated on blinded spiked urine samples from ten healthy volunteers. The estimated concentrations of clenbuterol were in accordance with their corresponding nominal values, as supported by the precision and accuracy data (relative standard deviation ≤5.4%, relative error ≤11%). The fulfillment of the World Anti-Doping Agency’s screening and confirmation criteria indicates that the proposed method is suitable for implementation in routine use in toxicologic and antidoping laboratories. Due to its high orthogonality and separation efficiency, the SPE–UHPLC–MS/MS method should also be easily adapted to the separation of structurally related compounds (such as clenbuterol metabolites). Thus, future antidoping applications could also include monitoring of clenbuterol metabolites, providing a longer detection widow. Full article
(This article belongs to the Special Issue Chromatographic and Electrophoretic Methods in Current Biomedical Analysis)
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13 pages, 620 KiB  
Article
GC-MS Analysis and Bioactivities of the Essential Oil of Suaeda aegyptiaca
by Elham Amin, Ahlam Elwekeel, Nasrah F. Alshariedh, Mohamed Sadek Abdel-Bakky and Marwa H. A. Hassan
Separations 2022, 9(12), 439; https://doi.org/10.3390/separations9120439 - 13 Dec 2022
Cited by 10 | Viewed by 2678
Abstract
Suaeda aegyptiaca is a halophytic plant widely growing in northeast Africa and Asia. The current study reports on the GC-MS analysis of S. aegyptiaca essential oil. The essential oil was prepared using three different methods: cold n-hexane extraction (CHE), hot n-hexane extraction (HHE), [...] Read more.
Suaeda aegyptiaca is a halophytic plant widely growing in northeast Africa and Asia. The current study reports on the GC-MS analysis of S. aegyptiaca essential oil. The essential oil was prepared using three different methods: cold n-hexane extraction (CHE), hot n-hexane extraction (HHE), and hydro-distillation extraction (HDE). The GC-MS analysis detected twenty-eight compounds in both CHE (97.28%) and HHE (97.35%) and twenty compounds in HDE (98.65%). 2-methyloctacosane (48.72%); 11-decyldocosane (29.20%); and 1, 2-benzenedicarboxylic acid diisooctyl ester (57.87%) were the main constituents in CHE, HHE, and HDE, respectively. Free radical scavenging activity testing using 2,2-diphenyl-1-picrylhydrazyl (DPPH) revealed the notable anti-oxidant potential of HDE (IC50 0.358 mg/mL) compared to ascorbic acid (IC50 0.264 mg/mL). Moreover, in vitro anti-inflammatory activity testing using COX-1 and COX-2 showed the notable activity of HDE (IC50 5.50 µg/mL and 2.59 µg/mL, respectively). The observed anti-inflammatory activity of HDE was further confirmed by the characteristic decrease in TNF-α levels in RAW264.7 to 572.20 Pg/mL compared to the decrease of 442.80 Pg/mL caused by the positive control (Celecoxib®). On the other hand, a cytotoxic activity investigation indicated that CHE was the most potent against the Caco-2 and HCT-116 cell lines (IC50 8.11 and 11.18 µg/mL, respectively), and it was closely followed by HHE (IC50 12.42 µg/mL) against the Caco-2 cell line. Collectively, S. aegyptiaca essential oil prepared by the hydro-distillation method exhibited notable anti-oxidant and anti-inflammatory activities, while the same essential oil prepared by solvent extraction methods displayed a characteristic cytotoxic activity against the Caco-2 and HCT-116 cell lines. These results confirmed that different extraction methods greatly influence the biological potential of an essential oil, which, in turn, is attributable to the different constituents in each extract Moreover, S. aegyptiaca was noted as a promising halophytic plant for more phytochemical and biological investigations. Full article
(This article belongs to the Special Issue Extraction and Characterization of Bioactive Based on Chromatography/Mass Spectrometry)
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18 pages, 2287 KiB  
Article
Bioprocessing of Agro-Industrial Waste for Maximization of Pectinase Production by a Novel Native Strain Aspergillus cervinus ARS2 Using Statistical Approach
by Anil R. Shet, Abdullatif Bin Muhsinah, Abdulfattah Y. Alhazmi, Sharanappa Achappa, Shivalingsarj V. Desai, Mater H. Mahnashi, Uday M. Muddapur, Aejaz Abdullatif Khan and Ibrahim Ahmed Shaikh
Separations 2022, 9(12), 438; https://doi.org/10.3390/separations9120438 - 13 Dec 2022
Cited by 5 | Viewed by 1843
Abstract
The demand for microbial pectinase has increased due to its vast applications in different industries. The current study dealt with the synthesis of pectinase by a novel native strain Aspergillus cervinus ARS2 using agro-industrial waste. Comparative studies conducted on pectinase production by submerged [...] Read more.
The demand for microbial pectinase has increased due to its vast applications in different industries. The current study dealt with the synthesis of pectinase by a novel native strain Aspergillus cervinus ARS2 using agro-industrial waste. Comparative studies conducted on pectinase production by submerged fermentation (SmF) and solid-state fermentation (SSF) showed that pectinase activity was more increased in SSF (44.51 ± 1.33 IU/mL) than in SmF (40.60 ± 1.15 IU/mL) when using orange peel as a substrate. Using SSF, one-factor-at-a-time (OFAT) studies were conducted, considering different process variables such as inoculum size, initial pH, incubation time, moisture content, incubation temperature, and substrate particle size, all of which affected the pectinase activity. OFAT results showed the highest pectinase activity at an inoculum size of 106 spores/mL (43.11 ± 1.06 U/mL), an incubation time of 6 days (43.81 ± 1.21 U/mL), a moisture content of 100% (44.30 ± 1.69 U/mL), a substrate particle size of 1.7 mm (42.06 ± 1.20 U/mL), an incubation temperature of 37 °C (45.90 ± 1.33 U/mL), and an initial pH of 4 (43.31 ± 0.89 U/mL). The identified significant process variables were then optimized by response surface methodology (RSM)-central composite design (CCD). The results showed optimum pectinase activity of 107.14 ± 0.71 IU/mL for a substrate particle size of 2 mm, an incubation temperature of 31.5 °C, an initial pH of 4.9, and a moisture content of 107%, which was obtained from the Minitab optimizer. By using statistical optimization, the pectinase production from the isolated novel fungal strain A. cervinus ARS2 was increased 2.38-fold. Therefore, the A. cervinus ARS2 strain can be further explored for large-scale pectinase production which could meet the growing industrial demands. Full article
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9 pages, 8567 KiB  
Article
Target Discovery of Flavonoids from Elymus nutans Griseb Using Medium- and High-Pressure Liquid Chromatography Combined with Online High-Performance Liquid Chromatography–1,1-diphenyl-2-picrylhydrazyl Detection
by Lili Sheng, Zhaofei Hou and Yufeng Hu
Separations 2022, 9(12), 437; https://doi.org/10.3390/separations9120437 - 13 Dec 2022
Viewed by 1439
Abstract
Forage-based nutrients constitute the main forage value of forage grass. Elymus nutans Griseb possesses a wide ecological adaptability, enhanced crude protein content, good palatability, and excellent genes. Herein, employing medium- (MPLC) and high-pressure liquid chromatography (HPLC), along with online HPLC-DPPH (OHD)-based identification, two [...] Read more.
Forage-based nutrients constitute the main forage value of forage grass. Elymus nutans Griseb possesses a wide ecological adaptability, enhanced crude protein content, good palatability, and excellent genes. Herein, employing medium- (MPLC) and high-pressure liquid chromatography (HPLC), along with online HPLC-DPPH (OHD)-based identification, two primary radical scavenging compounds were extracted and identified from the methanolic extract of Elymus nutans Griseb. With a starting material of 300 g of Elymus nutans Griseb, 5.95 g of the target DPPH suppressors fraction (Fr6) was separated following one cycle of MCI GEL® CHP20P medium pressure liquid chromatography. A Kromasil 100-5-Phenyl column was subsequently employed for further purification of the fraction, which yielded 432.16 mg of Fr62 (7.26% recovery) and 489.01 mg of Fr63 (8.22% recovery). The target compounds were then assessed based on their structure and purity, and two compounds (salcolin A and tricin) were extracted with > 95% purity. This newly designed procedure was highly effective for the targeted flavonoids, and high-purity radical scavenger extraction from forage extracts. This methodology can potentially provide a scientific basis for their quality evaluation. Full article
(This article belongs to the Topic Discovery of Bioactive Compounds from Natural Organisms and Their Molecular Mechanisms against Diseases)
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9 pages, 830 KiB  
Article
Essential Oils of Taxodium distichum Winter Leaves Obtained by Supercritical Carbon Dioxide Extraction Method and Hydrodistillation
by Nina Djapic
Separations 2022, 9(12), 436; https://doi.org/10.3390/separations9120436 - 13 Dec 2022
Cited by 2 | Viewed by 1799
Abstract
The extraction of Taxodium distichum needles was done using supercritical carbon dioxide extraction and hydrodistillation. SC CO2 extraction of T. distichum winter leaves was conducted at different pressures and temperatures using a central composite rotatable design. The optimal extraction conditions concerning the [...] Read more.
The extraction of Taxodium distichum needles was done using supercritical carbon dioxide extraction and hydrodistillation. SC CO2 extraction of T. distichum winter leaves was conducted at different pressures and temperatures using a central composite rotatable design. The optimal extraction conditions concerning the yield and α-tocopherol relative amount were determined by response surface methodology. The optimal conditions for the highest extraction yield of 3.97% were at 17.79 MPa and 62.70 °C and the highest α-tocopherol relative amount of 85.99 mg per 100 g of the plant material was at 22.07 MPa and 35.86 °C. The essential oil obtained by hydrodistillation contained 62 compounds and (-)-caryophyllene oxide was dominant (55.55%). The T. distichum essential oil obtained by SC CO2 extraction and hydrodistillation had a different composition. The desirable compounds influence the choice of the extraction method. Full article
(This article belongs to the Special Issue Novel Approach for Natural Product Separation from Plants)
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11 pages, 7270 KiB  
Article
Optimization Protocol of the PEG-Based Method for OSCC-Derived Exosome Isolation and Downstream Applications
by Tzong-Ming Shieh, Yu-Hsin Tseng, Shih-Min Hsia, Tong-Hong Wang, Wan-Chen Lan and Yin-Hwa Shih
Separations 2022, 9(12), 435; https://doi.org/10.3390/separations9120435 - 13 Dec 2022
Cited by 6 | Viewed by 4286
Abstract
The exosome precipitation method affects the purity of the exosome and the quality of the downstream application. Polymer-based precipitation is a cost-effective method widely used in different research fields. The percentage of the polymer should be modified in different cell types or liquid [...] Read more.
The exosome precipitation method affects the purity of the exosome and the quality of the downstream application. Polymer-based precipitation is a cost-effective method widely used in different research fields. The percentage of the polymer should be modified in different cell types or liquid biopsy before precipitation. This study aimed to optimize the protocol of the poly(ethylene glycol) (PEG)-based approach for extracting oral squamous cell carcinoma (OSCC)-derived exosomes, and its downstream applications. We used 8%, 10%, and 12% PEG to isolate the exosomes from the culture medium and compared the purity with that of the ultracentrifugation method. In addition, we extracted exosomal protein, DNA, and RNA, and tested the cell transfection efficiency for downstream application. The results reveal that 8% PEG and the medium mixture incubated at 4 °C overnight effectively precipitated exosomes of higher purity and more proper size and particle numbers compared with the ultracentrifuge method. PEG-precipitated exosomes cocultured with fibroblasts showed better transfection efficiency compared to exosomes alone. Therefore, 8% PEG is ideal for OSCC-derived exosome isolation and downstream applications. We recommend that the cost-effective PEG precipitation method be used for precipitating exosomes from OSCC cell experiments. Full article
(This article belongs to the Section Purification Technology)
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5 pages, 202 KiB  
Editorial
Recent Developments in Emerging Contaminants Determination and Treatment Technologies
by Mohammed J. K. Bashir and Amin Mojiri
Separations 2022, 9(12), 434; https://doi.org/10.3390/separations9120434 - 13 Dec 2022
Cited by 2 | Viewed by 1444
Abstract
The most fundamental need, which all people must have to maintain their life, is access to clean water [...] Full article
(This article belongs to the Section Environmental Separations)
12 pages, 2327 KiB  
Article
Capsule Phase Microextraction Combined with Chemometrics for the HPLC Determination of Amphotericin B in Human Serum
by Natalia Manousi, Anastasia Korpeti, Abuzar Kabir, Kenneth G. Furton and Constantinos K. Zacharis
Separations 2022, 9(12), 433; https://doi.org/10.3390/separations9120433 - 12 Dec 2022
Cited by 7 | Viewed by 2411
Abstract
This article discusses the use of a sorbent-based microextraction technique employing a capsule device to isolate amphotericin B (AMB) from human serum before analysis by high performance liquid chromatography (HPLC). AMB is a macrocyclic compound used for the treatment of invasive fungal infections. [...] Read more.
This article discusses the use of a sorbent-based microextraction technique employing a capsule device to isolate amphotericin B (AMB) from human serum before analysis by high performance liquid chromatography (HPLC). AMB is a macrocyclic compound used for the treatment of invasive fungal infections. Before determining AMB in human serum by HPLC, a sample preparation step is required. Capsule phase microextraction (CPME) integrates the stirring and filtration mechanisms in a single unit, simplifying the sample preparation procedure. Moreover, it results in fast extraction kinetics and high extraction efficiency, while it has proved to be a powerful tool for bioanalysis. Different sol–gel sorbent encapsulated microextraction capsules were investigated, and sol–gel Carbowax 20 M was finally chosen as the basis for the microextraction device. Accordingly, the sample preparation protocol was investigated using a face-centered central composite design to achieve good extraction performance. The optimum protocol was validated in terms of linearity, selectivity, limit of detection (LOD), limit of quantitation (LOQ), precision, and accuracy. The linear range of the developed approach was 0.10–10.0 μg mL−1. The LOD value was 0.03 μg mL−1, and the LOQ value was 0.10 μg mL−1. Method accuracy (expressed as relative recovery) was 87–113%, while the relative standard deviation of the repeatability (sr) and within-laboratory reproducibility (sR) were <12.4%. The sol–gel sorbent encapsulated microextraction capsules were reusable for at least 10 extraction cycles. All things considered, the proposed method exhibited good overall performance, and it could be used in bioanalysis for quality control, therapeutic drug monitoring and research purposes. Full article
(This article belongs to the Collection Feature Paper Collection in Section Chromatographic Separations)
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13 pages, 1843 KiB  
Article
Improved Quantitative Approach for Monitorization of Gangliosides Structural Diversity in Fungal Cell Factories by LC-MS/MS
by Javier-Fernando Montero-Bullón, Javier Martín-González, Gloria Muñoz-Fernández, Alberto Jiménez and José Luis Revuelta
Separations 2022, 9(12), 432; https://doi.org/10.3390/separations9120432 - 12 Dec 2022
Viewed by 1735
Abstract
Gangliosides are glycolipids occurring in higher animals, with a sphingoid core in the form of ceramide, bound to a glycan moiety including several units of sialic acid. Gangliosides are involved in important (patho)-physiological processes as components of cell membranes in humans, which has [...] Read more.
Gangliosides are glycolipids occurring in higher animals, with a sphingoid core in the form of ceramide, bound to a glycan moiety including several units of sialic acid. Gangliosides are involved in important (patho)-physiological processes as components of cell membranes in humans, which has led to intensive study and interest in production strategies. Their structural variability depends on the combination of a sphingoid base, a fatty acyl chain, and an attached oligosaccharide. The combinatorial diversity differs and grows exponentially in synthetic biology approaches, e.g., use of microbial cell factories. A specific analytical platform accounting for this complexity is not available to date. However, quantification of the intermediates of the whole biosynthetic route is needed to boost projects on biotechnological ganglioside production. In this study, a fast high-throughput quantitative LC-MS/MS methodology was developed to cover analysis of gangliosides, with a wider structural perspective adapted to fungal organisms. This work was achieved using metabolically engineered strains that further allowed to test detection in biological complex matrixes. Ganglioside backbones—hitherto uncharacterized—with the five most common fungal sphingoid bases and both simple and hydroxylated fatty acids were subjected to characterization. The addition of glycans to the polar head was also successfully monitored with up to 4 units—corresponding to GD3 which bears two sialic acid units and furthermore represents the common precursor for the whole ganglio-series. This platform represents an improved methodology to study the biochemical diversity associated to gangliosides for natural and metabolically engineered biosynthetic pathways. Full article
(This article belongs to the Special Issue Advances in Chromatographic Analysis of Bioactive Compounds)
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11 pages, 2112 KiB  
Article
Adsorption Properties and Preparative Separation of Flavonoids from Rhizoma Smilacis Glabrae Using Macroporous Resins
by Xiangyi Su, Xuan Zhang, Chunhua Wang, Guige Hou and Hongjuan Li
Separations 2022, 9(12), 431; https://doi.org/10.3390/separations9120431 - 11 Dec 2022
Cited by 3 | Viewed by 1686
Abstract
Astilbin (AST), isoastilbin (ISO), and engeletin (ENG) are the main flavonoids in Rhizoma Smilacis Glabrae (RSG) and have many biological activities. In this study, the adsorption kinetics of AST, ISO, and ENG on HPD-300 resin was investigated and their adsorption processes conformed to [...] Read more.
Astilbin (AST), isoastilbin (ISO), and engeletin (ENG) are the main flavonoids in Rhizoma Smilacis Glabrae (RSG) and have many biological activities. In this study, the adsorption kinetics of AST, ISO, and ENG on HPD-300 resin was investigated and their adsorption processes conformed to a pseudo-second-order kinetics equation. The fitting curves of the intraparticle diffusion model showed three linear stages and did not pass through the origin, meaning the adsorption process of the three flavonoids was controlled by boundary layer diffusion and intraparticle diffusion. Their adsorption isotherms were also constructed and could be well-fitted by the Langmuir equation. A low temperature was favorable for their adsorption. The relative adsorption capacity of ENG was significantly higher than those of the other two compounds, indicating that the substitution pattern on ring B has an important impact on the adsorption of flavonoids with resin. The separation process was optimized by dynamic adsorption/desorption experiments. After separation, the purities of AST, ISO, and ENG increased from 5.55%, 1.22%, and 0.45% to 27.46%, 6.14%, and 2.27%, respectively, and all the recoveries exceeded 75%. After that, the three compounds were further separated by preparative HPLC and silica gel chromatography. In the final product, the purities of AST, ISO, and ENG could reach above 98%. Full article
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12 pages, 3237 KiB  
Article
Inter-Comparisons of Major Ions and Organic Matter Using Aerodyne Aerosol Mass Spectrometer, Ion Chromatography and Sunset Lab Carbon Analyzer in Aged Aerosols from Okinawa in the Western North Pacific Rim
by Bhagawati Kunwar, Kazuhiro Torii, Akinori Takami and Kimitaka Kawamura
Separations 2022, 9(12), 430; https://doi.org/10.3390/separations9120430 - 11 Dec 2022
Cited by 2 | Viewed by 2199
Abstract
Inorganic components were measured in the aged ambient aerosols from Cape Hedo, Okinawa, an outflow region of East Asia, using online quadrupole Aerodyne aerosol mass spectrometer (Q-AMS) and offline ion chromatography (IC) and Sunset Lab carbon analyzer. Here, we performed an inter-comparison study [...] Read more.
Inorganic components were measured in the aged ambient aerosols from Cape Hedo, Okinawa, an outflow region of East Asia, using online quadrupole Aerodyne aerosol mass spectrometer (Q-AMS) and offline ion chromatography (IC) and Sunset Lab carbon analyzer. Here, we performed an inter-comparison study on nitrate (NO3−), ammonium (NH4+) and sulfate (SO42−) that were measured by IC and AMS. Sulfate and ammonium showed a good agreement between two instruments. However, abundances of NO3− by AMS are on average twice overestimated compared to nitrate obtained by IC. We also found that a significant amount of organic nitrogen (ON) was detected in the filter samples from Okinawa. The online measurement (Q-AMS) data and offline filter based-NO3− data need to be carefully evaluated when ON is abundantly present in aerosols. The OM/OC ratios derived from AMS are consistent with the bulk OMAMS/OCSunset ratios (2.1). This study demonstrates that the OM/OC of 2.1 is the reasonable criteria for more aged aerosols. Full article
(This article belongs to the Special Issue Extraction and Analysis of Emerging Environmental Pollutants)
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12 pages, 1164 KiB  
Article
Impact of Sunflower Meal Protein Isolate Supplementation on Pasta Quality
by Ahmed A. Zaky, Ahmed S. Hussein, Sayed Mostafa and A. M. Abd El-Aty
Separations 2022, 9(12), 429; https://doi.org/10.3390/separations9120429 - 10 Dec 2022
Cited by 7 | Viewed by 2554
Abstract
Globally, there is an increased demand for plant- and animal-derived proteins. However, animal-derived proteins are still expensive and expected to negatively impact the environment. Sunflower seeds, an excellent source of proteins, are one of the most critical oilseeds produced in the world markets. [...] Read more.
Globally, there is an increased demand for plant- and animal-derived proteins. However, animal-derived proteins are still expensive and expected to negatively impact the environment. Sunflower seeds, an excellent source of proteins, are one of the most critical oilseeds produced in the world markets. This study used sunflower meal protein isolate (SMPI), wheat flour (WF), and their blends to make pasta with good sensory features and higher nutritional value. The chemical and amino acid compositions, rheological properties, color attributes, cooking quality, sensory properties, and texture analysis of pasta were evaluated. SMPI showed a high protein content (87.12%) compared to WF (10.90%). The pasta was made from WF with supplementing SMPI at three concentrations (3.0, 6.0, and 9.0% w/w) to improve the nutritional quality. Farinograph parameters showed that water absorption, arrival time, dough development time, mixing tolerance index, dough weakening, and dough stability increased as the percentage of SMPI in the blends increased. The results also showed that the color (L*, a*, and b*) of pasta samples was darker as the mixing level of SMPI increased. The obtained sensorial results confirmed this result. The cooking quality of pasta revealed that the weight, volume, and cooking loss of prepared pasta with SMPI (3.0–9.0%) increased compared to the control sample (pasta with 100% WF). Moreover, sensory evaluation of pasta revealed that all samples were acceptable. Nonetheless, mouth feel and overall acceptability of pasta reinforced with 3.0 and 6.0% SMPI did not notably impact the pasta compared to the control sample, while flavor did not significantly influence the pasta with 3.0% SMPI. These findings demonstrated that pasta supplemented with SMPI could benefit the pasta industry, which requires a suitable technological process to obtain novel products. Full article
(This article belongs to the Section Analysis of Food and Beverages)
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18 pages, 7106 KiB  
Article
In Situ XRD, Raman Characterization, and Kinetic Study of CO2 Capture by Alkali Carbonate-Doped Na4SiO4
by Zhen Wang, Chenteng Sun, Qian Xu, Xingli Zou, Hongwei Cheng and Xionggang Lu
Separations 2022, 9(12), 428; https://doi.org/10.3390/separations9120428 - 10 Dec 2022
Cited by 5 | Viewed by 1938
Abstract
Sodium silicate, a new type of CO2 sorbent, has a relatively low cost, but its sorption reactivity is not yet good enough. Alkali carbonate doping is commonly used as an effective means to improve the CO2 uptake reactivity of solid sorbents. [...] Read more.
Sodium silicate, a new type of CO2 sorbent, has a relatively low cost, but its sorption reactivity is not yet good enough. Alkali carbonate doping is commonly used as an effective means to improve the CO2 uptake reactivity of solid sorbents. In this study, sodium orthosilicate, Na4SiO4, was synthesized and mixed with 5, 10, and 20 mol% of Li2CO3–Na2CO3 or Li2CO3–Na2CO3–K2CO3 as CO2 sorbents. The promotion of alkali carbonates on Na4SiO4 in CO2 capture was characterized using thermal analyses in an 80 vol% CO2–20 vol% N2 atmosphere. The phase evolution and structural transformations during CO2 capture were characterized by in situ XRD and Raman, and the results showed that the intermediate pyrocarbonate, C2O52−, which emerged from alkali carbonates, enhanced the CO2 capture of Na4SiO4 to form Na2CO3 and Na2SiO3 from 100 °C. Isothermal analyses showed that 10 mol% of Li2CO3–Na2CO3 was the optimal additive for Na4SiO4 to attain better CO2 uptake performance. The alkali carbonates were effective in reducing the activation energy for both chemisorption and bulk diffusion, improving the cycle stability of Na4SiO4. Full article
(This article belongs to the Special Issue Advances in CO2 Adsorptive Separation for CO2 Capture)
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14 pages, 2235 KiB  
Article
Experimental Design Assisted HPLC/UV and LC-MS/MS for Simultaneous Determination of Selected Veterinary Antibiotics in Broiler Chicken
by Mohamed A. Abdelshakour, Aziza E. Mostafa, Ghada M. Hadad, Dalia M. Hamed, Omayma M. El-Darder, Alaa El-Gindy, Roaa M. Khinkar, Mohammed M. Aldurdunji, Samar S. Murshid and Randa A. Abdel Salam
Separations 2022, 9(12), 427; https://doi.org/10.3390/separations9120427 - 10 Dec 2022
Viewed by 2341
Abstract
Antibiotics are used in the poultry industry to treat and prevent diseases. Their frequent use resulted in the appearance of antibiotic residuals in poultry meat, which is considered a serious public health issue. Among frequently used antibiotics are cefotaxime (CTX), ciprofloxacin (CIP), colistin [...] Read more.
Antibiotics are used in the poultry industry to treat and prevent diseases. Their frequent use resulted in the appearance of antibiotic residuals in poultry meat, which is considered a serious public health issue. Among frequently used antibiotics are cefotaxime (CTX), ciprofloxacin (CIP), colistin (CST), doxycycline (DOX), flumequine (FLU), sulfamethoxazole (SMZ), trimethoprim (TMP) and tylosin (TYL). This study aimed to develop an optimized and validated method for concurrent estimation of the eight antibiotics in broiler chicken samples based on an easy extraction method followed by HPLC-UV and LC/MS/MS analysis. An experimental design was used for the optimization of the extraction procedure. Optimal conditions for separation were determined by using a central composite design after studying (1) mobile phase initial concentration, (2) column temperature, and (3) flow rate. The method was validated on the bases of ICH guidelines. The detection limits ranged from 3 to 5 µg kg−1 for HPLC- UV and ranged from 0.01 to 0.05 µg kg−1 for LC/MS/MS, while quantification limits ranged from 10 to 16 µg kg−1 for HPLC- UV and ranged from 0.01 to 0.11 µg kg−1 for LC/MS/MS. The chromatographic techniques were utilized for the analysis of spiked broiler chicken samples at a concentration range from 30 to 300 µg kg−1) for HPLC-UV and 0.01–20 µg kg−1 for LC/MS/MS. The proposed methods were used for quantification of the residues of the studied antibiotics in real broiler samples obtained from local supermarkets in Ismailia governorate, Egypt. The detected levels of residual antibiotics were within the permissible limits. Full article
(This article belongs to the Special Issue Development of Highly Efficient Separation-Based Analytical Methods for Food Integrity Assurance)
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20 pages, 2980 KiB  
Article
Removal of Patent Blue Dye Using Ananas comosus-Derived Biochar: Equilibrium, Kinetics, and Phytotoxicity Studies
by Riti Thapar Kapoor, Mohd Rafatullah, Ahmed Muteb Aljuwayid, Mohamed A. Habila, Saikh Mohammad Wabaidur and Mahboob Alam
Separations 2022, 9(12), 426; https://doi.org/10.3390/separations9120426 - 10 Dec 2022
Cited by 9 | Viewed by 2221
Abstract
Patent Blue (PB) dye removal from an aqueous medium was investigated using pineapple fruit peel biochar (PFPB). The presence of functional groups and surface characteristics of PFPB was studied using Fourier transform infrared spectra (FTIR) and scanning electron microscopy (SEM). A study was [...] Read more.
Patent Blue (PB) dye removal from an aqueous medium was investigated using pineapple fruit peel biochar (PFPB). The presence of functional groups and surface characteristics of PFPB was studied using Fourier transform infrared spectra (FTIR) and scanning electron microscopy (SEM). A study was conducted to assess the pH effect, contact time, concentration of dye, biochar dose, speed of agitation, and temperature on removal of PB (Patent Blue) dye from an aqueous medium by PFPB. The highest 95% elimination of PB dye was reported at pH 2 by PFPB with 600 mg/L concentration of PB dye. Equilibrium studies divulged the favorable adsorption that followed the Langmuir isotherm with a monolayer uptake potential of 10.29 mg/g. Findings of kinetics disclosed that adsorption results were properly explained by the pseudo second-order model. The adsorption phenomenon was exothermic and spontaneous, as observed by thermodynamic variables. PFPB reflected a 37% uptake capacity of PB dye for up to five consecutive cycles in the adsorption and desorption study. A phytotoxicity study exhibited that PFPB-treated PB dye solution enhanced the growth of seedlings and biochemical constituents of lentils. The findings of the present study indicate the immense potential of pineapple fruit peel biochar for anionic dye removal from wastewater systems. Thus, pineapple fruit peel biochar can be utilized as a promising green sorbent for the elimination of Patent Blue dye in industrial effluents, as it is widely available and converts wastewater into reusable assets. Full article
(This article belongs to the Special Issue Removal of Emerging Pollutants and Environmental Analysis)
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15 pages, 3585 KiB  
Article
Advanced Treatment of Direct Dye Wastewater Using Novel Composites Produced from Hoshanar and Sunny Grey Waste
by Amna Akhtar, Muhammad Asif Hanif, Umer Rashid, Ijaz Ahmad Bhatti, Fahad A. Alharthi and Elham Ahmed Kazerooni
Separations 2022, 9(12), 425; https://doi.org/10.3390/separations9120425 - 9 Dec 2022
Cited by 17 | Viewed by 2417
Abstract
The present project is designed to investigate the potential of hoshanar and sunny grey marble wastes to remove direct violet 51 dye from wastewater using adsorption process. The effect of different parameters such as pH, adsorbent dose, initial dye concentration, and contact time [...] Read more.
The present project is designed to investigate the potential of hoshanar and sunny grey marble wastes to remove direct violet 51 dye from wastewater using adsorption process. The effect of different parameters such as pH, adsorbent dose, initial dye concentration, and contact time were studied to optimize the results of adsorption process. Different isothermic models (Temkin, Langmuir isotherm, Freundlich isotherm, Harkin Jura, and Dubinin-Radushkevich models) and kinetic models (pseudo-first order and pseudo-second order) were employed to adsorption data to find out the best fit model, i.e., Langmuir isotherm and pseudo-second order model. Marble waste composites were also characterized by using different techniques such as scanning electron microscopy (SEM) for surface morphology and Fourier transform infrared spectroscopy (FTIR) to determine chemical arrangements, structure, and functional groups of adsorbents. Hoshanar treated with a mixture of potassium ferricyanide, and sodium meta silicate showed maximum adsorption capacity of 105.31 mg/g as compared to untreated hoshanar (67.19.45 mg/g). So, the conversion of HM into HMPS makes it an affordable, efficient, and available adsorbent for wastewater treatment. Full article
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17 pages, 7812 KiB  
Article
The Effect of Initial Water Content and Density on the Swelling-Shrinkage and Cracking Characteristics of Compacted Clay
by Yuqing Zhong, Guanghua Cai and Gang Zeng
Separations 2022, 9(12), 424; https://doi.org/10.3390/separations9120424 - 9 Dec 2022
Cited by 6 | Viewed by 2313
Abstract
The swelling-shrinkage and cracking characteristics of compacted clay under the coupling effect of initial conditions are rarely studied. The dry-wet cycle test of compacted clay with varying initial water contents and densities was performed in this study; the size and cracking conditions were [...] Read more.
The swelling-shrinkage and cracking characteristics of compacted clay under the coupling effect of initial conditions are rarely studied. The dry-wet cycle test of compacted clay with varying initial water contents and densities was performed in this study; the size and cracking conditions were investigated. The results showed that when the initial moisture content was 21% and the dry density was 1.65 g/cm3, the longitudinal expansion amount of the compacted clay was relatively small. However, it was rather large when the initial water content was 17% and 19%. Under the same dry density, the final vertical shrinkage ratio of the sample with a water content of 21% was the smallest, while that of the samples with a water content of 23% and 25% was rather big. Under the same water content, the final vertical shrinkage ratio decreased with the increase in dry density. After three wetting-drying cycles, compacted clay with a dry density of 1.65 g/cm3 and an optimal initial water content of 21% produced the fewest cracks and had the lowest cracking factor (CF) (only 7.58%). The compacted clay specimens with the dry densities of 1.55 g/cm3 and 1.60 g/cm3 had rather significant cracking at the same initial moisture content of 21%. The mercury intrusion porosimetry (MIP) test demonstrated that in the first two dry and wet cycles, the distribution of large pores decreased and that of tiny pores increased. After the third cycle, the distribution of small and medium pores decreased slightly. The results of this study will provide theoretical guidance for selecting cover soils in landfills. Full article
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19 pages, 4175 KiB  
Article
Valorization of Raw Coffee Beans (Coffea arabica and Coffea canephora) through Solvent Development and Extraction of Bioactive Compounds
by Letícia Zander Ronko, Maria Alice Antoniassi, Karina Mayumi Ueda, Fernando Castro Leal, Aline Theodoro Toci, Luciana Igarashi-Mafra, Marcos R. Mafra and Fabiane Oliveira Farias
Separations 2022, 9(12), 423; https://doi.org/10.3390/separations9120423 - 9 Dec 2022
Viewed by 2384
Abstract
Raw coffee beans are seen as valuable sources of bioactive compounds, such as alkaloids and chlorogenic acids. In this study, an efficient and eco-friendly method for the simultaneous extraction of caffeine, trigonelline, and chlorogenic acids from raw beans of two coffee species was [...] Read more.
Raw coffee beans are seen as valuable sources of bioactive compounds, such as alkaloids and chlorogenic acids. In this study, an efficient and eco-friendly method for the simultaneous extraction of caffeine, trigonelline, and chlorogenic acids from raw beans of two coffee species was developed, using green solvents and an unconventional method of extraction (assisted by ultrafast rotary disintegrator/homogenizer (UT-AE)). The experimental extraction conditions were optimized according to a completely randomized design (CRD), considering the following variables: solvent type (four deep eutectic solvents (DESs), water, and aqueous choline chloride solution (50 wt.%); temperature (25, 45, and 65 °C); and extraction technique (solid-liquid extraction with agitated heating and assisted by ultrafast rotary disintegrator/homogenizer). The extract obtained with choline chloride solution (50 wt.%) exhibited high total phenolic compounds and the highest antioxidant capacity. An analysis using high-performance liquid chromatography with a diode array detector (HPLC-DAD) indicated the presence of chlorogenic acids, caffeine, and trigonelline in all the extracts, in different amounts. The results obtained by the analysis of phenolic compounds and HPLC indicated that the aqueous solution of choline chloride (50% wt.%) was the most suitable solvent for the extraction of chlorogenic acids, while the water-based extracts showed high values of caffeine and trigonelline. DESs, in turn, seems to promote a protective effect on the antioxidant activity of biomolecules. Full article
(This article belongs to the Section Materials in Separation Science)
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23 pages, 10450 KiB  
Article
Effect of Fluoride Ions on the Surface Dissolution of Vanadium-Bearing Biotite
by Yuanyuan Tao, Guohua Ye, Hao Zhang, Yujie Hu, Qi Zuo, Xiao Wang, Siqin Zhu, Xuanxiong Kang, Yun Zhang, Xinyue Xiang, Yiyang Rong and Changxu Song
Separations 2022, 9(12), 422; https://doi.org/10.3390/separations9120422 - 8 Dec 2022
Cited by 2 | Viewed by 1496
Abstract
In shale vanadium ore, vanadium is mainly formed as a low-V(III) homogeneous phase to partially replace Si and exists in the lattice structure of aluminosilicate minerals such as biotite. During the acid leaching of shale vanadium ore, an activator is needed to effectively [...] Read more.
In shale vanadium ore, vanadium is mainly formed as a low-V(III) homogeneous phase to partially replace Si and exists in the lattice structure of aluminosilicate minerals such as biotite. During the acid leaching of shale vanadium ore, an activator is needed to effectively extract vanadium. Using biotite as a tetrahedral structure doped with Aluminum-Silicon tetrahedron structure, the interaction between leaching-agent ions (H+), activator ions (F−), and vanadium-containing biotite surface was discussed by DFT quantum chemical calculations. The dissolution behavior of activator fluoride ions on the surface of vanadium-bearing biotite during sulfuric acid leaching was revealed. According to the simulated leaching results, the oxygen on the biotite surface first absorbed hydrogen ions to undergo complete hydroxylation, and then combined with hydrogen ions to form water molecules. However, in the presence of activator (NaF), fluoride ions were adsorbed on the surface cations, which catalyzed the formation of water molecules and promoted the dissolution of surface cations. SEM–EDS analysis showed that the surface of vanadium-bearing minerals became very irregular, and the number of voids and cracks greatly increased. At the same time, XPS showed that the addition of activator fluoride ions destroyed the Al-O tetrahedron structure. Many Al and V atoms dissolved in the solution, which improved the leaching rate of vanadium. Full article
(This article belongs to the Special Issue Mineral Flotation)
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