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Separations, Volume 11, Issue 4 (April 2024) – 40 articles

Cover Story (view full-size image): Oil pollution, resulting from oil spills and large discharges of oily wastewater, poses a significant threat to the global ecological and economic environment. Recently, superwetting materials manufactured via ultrafast lasers for oil–water separation have garnered widespread attention due to their easy preparation strategies and excellent separation properties. This review makes progress in systematically discussing and comparing the preparation techniques of the superhydrophobic/superoleophilic, superhydrophilic/superoleophobic, and superamphiphilic or reversible-wettability materials with their corresponding separation performance, serving as a reference for the development of innovative superwetting materials for versatile oil–water separation in complex scenarios using ultrafast laser processing. View this paper
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27 pages, 4865 KiB  
Article
The Removal of As(III) Using a Natural Laterite Fixed-Bed Column Intercalated with Activated Carbon: Solving the Clogging Problem to Achieve Better Performance
by Régie Dimanche Ouedraogo, Corneille Bakouan, Abdoul Karim Sakira, Brahima Sorgho, Boubié Guel, Touridomon Issa Somé, Anne-Lise Hantson, Eric Ziemons, Dominique Mertens, Philippe Hubert and Jean-Michel Kauffmann
Separations 2024, 11(4), 129; https://doi.org/10.3390/separations11040129 - 22 Apr 2024
Viewed by 529
Abstract
Natural laterite fixed-bed columns intercalated with two types of layers (inert materials, such as fine sand and gravel, and adsorbent materials, such as activated carbon prepared from Balanites aegyptiaca (BA-AC)) were used for As(III) removal from an aqueous solution. Investigations were carried out [...] Read more.
Natural laterite fixed-bed columns intercalated with two types of layers (inert materials, such as fine sand and gravel, and adsorbent materials, such as activated carbon prepared from Balanites aegyptiaca (BA-AC)) were used for As(III) removal from an aqueous solution. Investigations were carried out to solve the problem of column clogging, which appears during the percolation of water through a natural laterite fixed-bed column. Experimental tests were conducted to evaluate the hydraulic conductivities of several fixed-bed column configurations and the effects of various parameters, such as the grain size, bed height, and initial As(III) concentration. The permeability data show that, among the different types of fixed-bed columns investigated, the one filled with repeating layers of laterite and activated carbon is more suitable for As(III) adsorption, in terms of performance and cost, than the others (i.e., non-intercalated laterite; non-intercalated activated carbon, repeating layers of laterite and fine sand; and repeating layers of laterite and gravel). A study was carried out to determine the most efficient column using breakthrough curves. The breakthrough increased from 15 to 85 h with an increase in the bed height from 20 to 40 cm and decreased from 247 to 32 h with an increase in the initial As(III) concentration from 0.5 to 2 mg/L. The Bohart–Adams model results show that increasing the bed height induced a decrease in the kAB and N0 values. The critical bed depths determined using the bed depth service time (BDST) model for As(III) removal were 15.23 and 7.98 cm for 1 and 20% breakthroughs, respectively. The results show that the new low-cost adsorptive porous system based on laterite layers with alternating BA-AC layers can be used for the treatment of arsenic-contaminated water. Full article
(This article belongs to the Special Issue Development and Applications of Porous Materials in Adsorptions)
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22 pages, 1456 KiB  
Review
Bioactives in Cocoa: Novel Findings, Health Benefits, and Extraction Techniques
by Kristina Tušek, Davor Valinger, Tamara Jurina, Tea Sokač Cvetnić, Jasenka Gajdoš Kljusurić and Maja Benković
Separations 2024, 11(4), 128; https://doi.org/10.3390/separations11040128 - 19 Apr 2024
Viewed by 511
Abstract
Theobroma cacao L. seeds, commonly known as cocoa beans, are the foundation for cocoa and chocolate production. Following harvest, these beans undergo a multi-step processing chain including fermentation, drying, roasting, and grinding. This process yields cocoa solids, cocoa butter, and cocoa powder—all fundamental [...] Read more.
Theobroma cacao L. seeds, commonly known as cocoa beans, are the foundation for cocoa and chocolate production. Following harvest, these beans undergo a multi-step processing chain including fermentation, drying, roasting, and grinding. This process yields cocoa solids, cocoa butter, and cocoa powder—all fundamental ingredients in the food and beverage industry. Beyond its sensory appeal (flavor, aroma, and texture), cocoa has garnered significant interest for its potential health benefits attributed to a rich profile of bioactive compounds. Cocoa is a well-documented source of polyphenolics, specifically flavanols, alongside methylxanthines, phytosterols, and dietary fibers. These constituents have been associated with a diverse range of bioactivities, including antioxidant, anti-carcinogenic, anti-diabetic, anti-inflammatory, anti-obesity, and anti-allergenic properties, potentially contributing to overall health maintenance. Efficient extraction techniques are crucial for maximizing the recovery of these valuable bioactive components from cocoa plant material. Modern methods are continuously being explored to optimize this process. This review focuses on the established health benefits associated with the bioactive compounds present in cocoa. Additionally, it will explore and discuss contemporary approaches for the extraction of these bioactive compounds from this plant source. Full article
(This article belongs to the Special Issue Research Progress for Isolation of Plant Active Compounds)
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21 pages, 4151 KiB  
Article
Cymbopogon citratus Water Extract and Methyl Jasmonate Improve Polyunsaturated Fatty Acid Metabolism in Taiwanofungus camphoratus Mycelia
by Yeyan Wen, Zixuan Lin, Dongmei Lin, Biaosheng Lin, Gexin Chen, Zhanxi Lin and Jing Li
Separations 2024, 11(4), 127; https://doi.org/10.3390/separations11040127 - 19 Apr 2024
Viewed by 778
Abstract
A rare medicinal fungus called Taiwanofungus camphoratus gives people resistance to illness. In order to effectively obtain high−quality T. camphoratus mycelia, we added Cymbopogon citratus (lemongrass) water extract (LWE), which was prepared using hot water and dry lemongrass leaves and methyl jasmonate (MJ) [...] Read more.
A rare medicinal fungus called Taiwanofungus camphoratus gives people resistance to illness. In order to effectively obtain high−quality T. camphoratus mycelia, we added Cymbopogon citratus (lemongrass) water extract (LWE), which was prepared using hot water and dry lemongrass leaves and methyl jasmonate (MJ) as an additive, in order to cultivate T. camphoratus mycelia. The components of LWE were identified by gas chromatography–mass spectrometry as glucose (61.66%) and galactose (17.10%). Compare to the basal medium, 0.5–2.5 g·L−1 LWE and 5–25 μmol·L−1 MJ can enhance the proliferation of mycelia and the metabolism of polyunsaturated fatty acids (PUFAs). Among them, the T. camphoratus mycelia growth rate increased to 1.292 ± 0.01 cm·d−1 and 1.285 ± 0.05 cm·d−1, improving by 2.5 g·L−1 LWE and 25 μmol·L−1 MJ, respectively. PUFAs are mainly composed of linoleic acid (LA) and oleic acid (OA). The contents of LA and OA were 0.28 ± 0.02 mg·g−1 and 0.23 ± 0.05 mg·g−1 after MJ treatment, while the contents of LA and OA were 0.08 ± 0.03 mg·g−1 and 0.05 ± 0.05 mg·g−1 after LWE treatment. Transcriptome analyses revealed that 367 and 232 genes within MJ and LWE treatment were significantly different from the basal medium. Out of 13 unigenes, FAD22, SCD, and FAD21 had the highest expression levels according to the quantitative RT−PCR result. The bioinformatics analysis showed that three genes are closely related to the M8 chromosome of T. camphoratus, and they are hydrophobic transmembrane proteins. The identification and investigation of fatty acid genes in T. camphoratus mycelia will be improved by our findings. Full article
(This article belongs to the Special Issue Research Progress for Isolation of Plant Active Compounds)
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24 pages, 5748 KiB  
Review
Laser Manufacturing of Superwetting Oil–Water Separation Materials: A Review
by Wei Xiong, Linfeng Zhu, Ruisong Jiang and Chaolang Chen
Separations 2024, 11(4), 126; https://doi.org/10.3390/separations11040126 - 19 Apr 2024
Viewed by 600
Abstract
The frequent occurrence of oil spills and the massive discharge of oily wastewater pose a significant threat to sustainable and healthy human development. Therefore, it is of importance to effectively separate oil–water mixtures. Inspired by nature, many superwetting surfaces/materials for oil–water separation have [...] Read more.
The frequent occurrence of oil spills and the massive discharge of oily wastewater pose a significant threat to sustainable and healthy human development. Therefore, it is of importance to effectively separate oil–water mixtures. Inspired by nature, many superwetting surfaces/materials for oil–water separation have been developed in recent years. However, these surfaces/materials are subject to certain limitations and are unable to fully meet practical needs. With the advancement of laser technology, a novel solution has been provided for fabricating superwetting oil–water separation materials. Based on the design theory and separation mechanism, this paper summarizes the research progress of the laser-fabricated superwetting surfaces/materials for oil–water separation in recent years. First, the basic wetting theory, design strategy, and oil–water separation mechanism of the laser-fabricated materials are introduced in detail. Subsequently, the laser-fabricated oil–water separation materials, including superoleophilic/superhydrophobic materials, superhydrophilic/superoleophobic materials, and materials with reversible or superamphiphilic wettability, are systematically summarized and analyzed. Finally, the challenges and future research directions of laser-fabricated superwetting oil–water separation materials are discussed. Full article
(This article belongs to the Special Issue Advanced Oil–Water Separation Technology)
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19 pages, 4852 KiB  
Article
Adsorption of Fluoride from Water Using Aluminum-Coated Silica Adsorbents: Comparison of Silica Sand and Microcrystalline Silica
by Kiana Modaresahmadi, Amid P. Khodadoust and James Wescott
Separations 2024, 11(4), 125; https://doi.org/10.3390/separations11040125 - 19 Apr 2024
Viewed by 633
Abstract
Two aluminum-coated silica adsorbents were evaluated using silica sand and microcrystalline silica as aluminum-oxide-based adsorbents with different crystalline silica base materials. The aluminum coating contained mainly amorphous aluminum oxides for both aluminum-coated silica adsorbents. The adsorption of fluoride onto both adsorbents was favorable [...] Read more.
Two aluminum-coated silica adsorbents were evaluated using silica sand and microcrystalline silica as aluminum-oxide-based adsorbents with different crystalline silica base materials. The aluminum coating contained mainly amorphous aluminum oxides for both aluminum-coated silica adsorbents. The adsorption of fluoride onto both adsorbents was favorable according to the Langmuir and Freundlich adsorption equations, while the physical adsorption of fluoride occurred for both adsorbents according to the Dubinin–Raduskevish (D-R) equation. The adsorption of fluoride was stronger for aluminum-coated silica sand based on adsorption parameters from the Langmuir, Freundlich, and D-R adsorption equations, with the stronger binding of fluoride likely due to the observed greater specific adsorption. The adsorption capacity determined using the Langmuir equation was about 7 times greater for aluminum-coated microcrystalline silica primarily due to the 1.22-orders-of-magnitude-larger surface area of aluminum-coated microcrystalline silica, whereas the surface-normalized adsorption capacity was 2.4 times greater for aluminum-coated silica sand, possibly due to more aluminum being present on the surface of silica sand. Fluoride adsorption occurred over a broad pH range from 3 to 10 for both adsorbents, with nearly the same pHPZC of 9.6, while aluminum-coated microcrystalline silica displayed a higher selectivity for fluoride adsorption from different natural water sources. Full article
(This article belongs to the Section Materials in Separation Science)
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10 pages, 2659 KiB  
Communication
Experimental Study on the Separation of Lithium and Imidazolium Ions Using a Cation Exchange Membrane
by Jingyi Xue, Xiang Meng, Runci Wang, Zhongwei Yuan and Weifang Zheng
Separations 2024, 11(4), 123; https://doi.org/10.3390/separations11040123 - 19 Apr 2024
Viewed by 655
Abstract
The separation of Li+ and [Bmim]+(1-Butyl-3-methylimidazolium) using a cation exchange membrane in an electric field is studied in this work. The effects of the type of cation exchange membrane, current density, total cation concentration, temperature, and anion types on the [...] Read more.
The separation of Li+ and [Bmim]+(1-Butyl-3-methylimidazolium) using a cation exchange membrane in an electric field is studied in this work. The effects of the type of cation exchange membrane, current density, total cation concentration, temperature, and anion types on the separation efficiency are investigated. The results indicate that it is feasible to achieve the efficient separation of Li+ and [Bmim]+ using the selectivity of cation exchange membranes under an electric field. The CIMS membrane (a type of cation exchange membrane produced by ASTOM Corporation) shows obvious selectivity of Li+ from [Bmim]+. When the current density is 5 mA/cm2 and the feed concentrations of Li+ and [Bmim]+ are 0.3 mol/L and 0.2 mol/L, respectively, the selective transport coefficient of CIMS can reach 5.9 in the first 120 min of the process. The separation efficiency can be effectively improved by reducing the current density and increasing the total cation concentration. Decreasing the feed temperature can slightly improve the separation efficiency. Changing the type of anion in the feed from chloride to acetate has no detectable effect on the separation. Full article
(This article belongs to the Topic Membrane Separation Technology Research)
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15 pages, 4413 KiB  
Article
Extraction of Copper from Copper Concentrate by Indigenous Association of Iron-Oxidizing Bacteria
by Arevik Vardanyan, Ruiyong Zhang, Anna Khachatryan, Zaruhi Melkonyan, Arshavir Hovhannisyan, Sabine Willscher, Andreas Kamradt, Manuel Jost, Yimeng Zhang, Can Wang and Narine Vardanyan
Separations 2024, 11(4), 124; https://doi.org/10.3390/separations11040124 - 18 Apr 2024
Viewed by 1020
Abstract
Bioleaching of Cu from the copper concentrate of Armanis gold-bearing polymetallic ore (Armenia) was investigated. The main objective was revealing high active bacteria and their association, as well as optimizing the bioleaching process with their application to ensure the most efficient recovery of [...] Read more.
Bioleaching of Cu from the copper concentrate of Armanis gold-bearing polymetallic ore (Armenia) was investigated. The main objective was revealing high active bacteria and their association, as well as optimizing the bioleaching process with their application to ensure the most efficient recovery of copper from the tested concentrate. To obtain optimal bacterial associations, bottom-up and top-down approaches were used. Bioleaching of copper concentrate was carried out using pure cultures of iron- and sulfur-oxidizing bacteria and their mixed culture, as well as indigenous bacterial consortium. Comparative studies of copper bioleaching by mixed cultures of Acidithiobacillus caldus, Leptospirillum ferriphilum CC, Sulfobacillus thermosulfidooxidans 6, and indigenous consortium Arm of iron-oxidizing bacteria were performed. At the beginning of bioleaching, the amounts of extracted copper by mixed culture and Arm consortium were equal; afterward, between 20–27 days, the Arm indigenous consortium showed significantly higher activity in terms of copper extraction. In parallel, mineralogical and liberation analyses of feed material and bioleaching residues were performed. Full article
(This article belongs to the Section Purification Technology)
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25 pages, 7019 KiB  
Review
The Removal of Per- and Poly-Fluoroalkyl Substances from Water: A Review on Destructive and Non-Destructive Methods
by Natalia Malouchi, Stella Chatzimichailidou, Athanasia K. Tolkou, George Z. Kyzas, Loris Calgaro, Antonio Marcomini and Ioannis A. Katsoyiannis
Separations 2024, 11(4), 122; https://doi.org/10.3390/separations11040122 - 18 Apr 2024
Viewed by 907
Abstract
PFAS, or per- and poly-fluoroalkyl substances, are a broad group of man-made organic compounds that are very persistent, mobile, and tend to bioaccumulate. Their removal from different environmental media is becoming increasingly important because they are associated with a multitude of (eco)toxicological effects [...] Read more.
PFAS, or per- and poly-fluoroalkyl substances, are a broad group of man-made organic compounds that are very persistent, mobile, and tend to bioaccumulate. Their removal from different environmental media is becoming increasingly important because they are associated with a multitude of (eco)toxicological effects on both humans and the environment. PFAS are detected in wastewater, groundwater, drinking water, and surface water, with the subcategories of PFOS and PFOA being the most detected. These organic compounds are divided into polymeric and non-polymeric groups. Non-polymeric PFAS are of great research interest due to their frequent detection in the environment. Numerous methods have been applied for the removal of PFAS and are divided into destructive and non-destructive (separation) techniques. Given the strength of the C–F bond, the destruction of PFAS is challenging, while for most of the separation techniques, the management of isolated PFAS requires further consideration. Most of the techniques have been applied to small-scale applications and show some limitations for larger applications, even though they are promising. Adsorption is an environmentally sustainable, economical, and high-performance technique that is applied to remove several classes of emerging pollutants from water. In this review, the use of various types of adsorbents for PFAS removal from water is reported, as well as the expected adsorption mechanisms. There are several technologies being considered and developed to manage PFAS; however, they are still in the experimental stage, with each showing its appeal for potential larger applications. Full article
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15 pages, 6185 KiB  
Article
The Molecular Identification and Comprehensive Analysis of Klebsiella pneumoniae Isolated from Industrial Wastewater
by Kai Yan, Changfu Li, Weiyu Wang, Juan Guo and Haifeng Wang
Separations 2024, 11(4), 121; https://doi.org/10.3390/separations11040121 - 17 Apr 2024
Viewed by 701
Abstract
Industrial wastewater typically contains many organic and inorganic pollutants and is also contaminated by various microorganisms. Microbial species in industrial wastewater have not been extensively investigated. In this experiment, a Klebsiella pneumoniae strain was isolated for the first time from industrial wastewater containing [...] Read more.
Industrial wastewater typically contains many organic and inorganic pollutants and is also contaminated by various microorganisms. Microbial species in industrial wastewater have not been extensively investigated. In this experiment, a Klebsiella pneumoniae strain was isolated for the first time from industrial wastewater containing a high concentration of sulfate and phosphate. Mass spectrometry, genetic analysis, and biochemical identification were conducted to understand the genetic and biochemical characteristics of this Klebsiella pneumoniae strain recovered from industrial wastewater. Growth experiments revealed that it exhibited an excellent growth rate in nutrient broth. Further analyses showed that the strain was sensitive to most antibiotics but resistant to chloramphenicol and nitrofurantoin. It also exhibited significant resistance to piperacillin/tazobactam and cefotaxime/clavulanic acid. Resistance gene experiments indicated the presence of gyrA, OqxB, and ParC genes associated with antibiotic resistance in the isolated Klebsiella pneumoniae strain. Proteomics uncovered the following three proteins related to drug resistance: the multi-drug resistant outer membrane protein MdtQ, the multi-drug resistant secretion protein, and the modulator of drug activity B, which are coexistent in Klebsiella pneumoniae. Proteomics and bioinformatics analyses further analyzed the protein composition and functional enrichment of Klebsiella pneumoniae. The isolation of Klebsiella pneumoniae from a high concentration in sulfate and phosphate industrial wastewater provides a new direction for further research on the characteristics and drug resistance traits of industrial wastewater microorganisms and the potential risks they may pose when released into the environment. Full article
(This article belongs to the Topic Sustainable Technologies for Water Purification)
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18 pages, 10033 KiB  
Article
Enhancing Recovery of Ultra-Fine Magnetite from Low-Iron-Grade Cyanidation Tailings by Optimizing Flow Field Parameters of Low-Intensity Magnetic Separation (LIMS)
by Yingjie Chen, Yaxiong Jiang, Yongjun Xian and Luzheng Chen
Separations 2024, 11(4), 120; https://doi.org/10.3390/separations11040120 - 16 Apr 2024
Viewed by 658
Abstract
The characteristics of iron minerals in cyanidation tailings with a low iron grade were determined via chemical composition analysis, iron phase analysis, and mineral liberation analysis (MLA). The results showed that the cyanidation tailings contained 15.68% iron, mainly occurring in the form of [...] Read more.
The characteristics of iron minerals in cyanidation tailings with a low iron grade were determined via chemical composition analysis, iron phase analysis, and mineral liberation analysis (MLA). The results showed that the cyanidation tailings contained 15.68% iron, mainly occurring in the form of magnetite (19.66%) and limonite (79.91%), in which 16.52% magnetite and 65.90% limonite particles were fully liberated. Most ultra-fine magnetite grains were adjacent and wrapped with limonite to form complex intergrowths, which resulted in low-efficiency magnetite recovery in low-intensity magnetic separation (LIMS) and adversely affected the downstream high-gradient magnetic separation (HGMS) process. Thus, in this work, the optimization of the flow field was proposed to enhance the separation of ultra-fine magnetite from the cyanidation tailings using pilot-scale LIMS separation, and the controllable parameters (including feed flow, separation gap, drum rotating speed, and solid weight) affecting ultra-fine magnetite capture were investigated. Under optimized conditions, a high-grade magnetite concentrate assaying 63.31% Fe with 86.46% magnetite recovery was produced, which, respectively, increased by 0.76% and 15.22%, compared with those obtained from industrial production. In addition, from the flow dynamics simulation, it was found that the magnetite particles in the −6 µm ultra-fine fraction were lost much more easily than those of coarser fractions due to the relatively enhanced hydrodynamic drag force acting on the particles compared with the magnetic force. However, this loss would be effectively reduced with the regulation and control of the flow field. The iron recoveries in the −16~+6 µm and −6 µm fractions of magnetite concentrate increased by 3.66% and 4.42%, respectively, under optimized hydrodynamic conditions. This research outcome provides a valuable reference for the economic and effective utilization of iron resources from such solid wastes. Full article
(This article belongs to the Special Issue Application of Magnetic Separation Technology in Green Production)
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15 pages, 2182 KiB  
Article
Combination of Natural Deep Eutectic Solvents and Nano-Liquid Chromatography towards White Analytical Chemistry: A Practical Application
by Álvaro Santana-Mayor, Giovanni D’Orazio, Salvatore Fanali, Miguel Ángel Rodríguez-Delgado and Bárbara Socas-Rodríguez
Separations 2024, 11(4), 119; https://doi.org/10.3390/separations11040119 - 16 Apr 2024
Viewed by 831
Abstract
In this work, a green and practical analytical method based on natural deep eutectic solvents (NADES) as extraction agents and nano-liquid chromatography as a separation technique was developed. To demonstrate the applicability of the methodology, alkylphenols and bisphenol A were evaluated as model [...] Read more.
In this work, a green and practical analytical method based on natural deep eutectic solvents (NADES) as extraction agents and nano-liquid chromatography as a separation technique was developed. To demonstrate the applicability of the methodology, alkylphenols and bisphenol A were evaluated as model compounds in olive and sunflower oils as model fatty samples by liquid–liquid microextraction. With this aim, several NADES based on mixtures of choline chloride with glycerol, lactic, ascorbic, and citric acids or glycerol with amino acids were evaluated as potential extraction solvents. In addition, to select the most suitable stationary phase for the separation of this group of contaminants, some stationary phases were tested, including Pinnacle II phenyl, Cogent Bidentate C18™, and XBridge® C18. The last one provided the best performance with an analysis time of 11 min. To solve the problem of the compatibility of hydrophilic NADES with chromatographic systems without harming the solubility of analytes, different aqueous organic mixtures were tested. Methanol/water mixtures were the most suitable as an injection solvent. Finally, following the White Analytical Chemistry principles, different tools were used to evaluate the greenness, the practicality, and applicability of the method based on the Analytical Eco-Scale, the Analytical GREEnness metric approach, and the Blue Applicability Grade Index. Full article
(This article belongs to the Collection Feature Paper Collection in Section Chromatographic Separations)
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1 pages, 134 KiB  
Correction
Correction: Saafie et al. Effect of Hydrothermal Conditions on Kenaf-Based Carbon Quantum Dots Properties and Photocatalytic Degradation. Separations 2023, 10, 137
by Nabilah Saafie, Nonni Soraya Sambudi, Mohd Dzul Hakim Wirzal and Suriati Sufian
Separations 2024, 11(4), 118; https://doi.org/10.3390/separations11040118 - 15 Apr 2024
Viewed by 373
Abstract
There was an error in the original publication [...] Full article
(This article belongs to the Section Environmental Separations)
22 pages, 8124 KiB  
Article
Antioxidant and Hepatoprotective Activity of an Extract from the Overground Parts of Phlomis russeliana Lag. ex Benth
by Magdalena Kondeva-Burdina, Aleksandar Shkondrov, Georgi Popov, Vasil Manov and Ilina Krasteva
Separations 2024, 11(4), 117; https://doi.org/10.3390/separations11040117 - 13 Apr 2024
Viewed by 511
Abstract
An evaluation of the possible hepatotoxicity/hepatoprotective effects of a defatted extract of the above ground parts of Phlomis russeliana was conducted in vitro and in vivo. The extract was tested in vitro on hepatocytes alone and in a carbon tetrachloride (CCl4)-bioactivation [...] Read more.
An evaluation of the possible hepatotoxicity/hepatoprotective effects of a defatted extract of the above ground parts of Phlomis russeliana was conducted in vitro and in vivo. The extract was tested in vitro on hepatocytes alone and in a carbon tetrachloride (CCl4)-bioactivation model. The same toxic substance was used for the in vivo evaluation on old Wistar rats. The extract was standardised via high performance liquid chromatography (HPLC) by the quantification of total flavonoids and verbascoside. Gallic acid equivalents were used to express the content of total phenolic compounds. The identification of flavonoids in this species was undertaken for the first time. The extract was not statistically hepatotoxic in vitro on the isolated rat hepatocytes. In the CCl4-induced hepatotoxicity model, the extract had a hepatoprotective effect, which was concentration-dependant (the highest at 50 µg/mL). An in vivo study on old rats confirmed the observed antioxidant and hepatoprotective effects. The histological findings were favourable for the rats, given the extract and CCl4 in combination. They had an unchanged organ structure, which is commensurable with these animals, treated with a combination of CCl4 and silymarin. Full article
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13 pages, 3640 KiB  
Article
Synthesis of Quaternary-Ammonium-Lignin-Based Ionic Liquids and Comparison of Extraction Behavior of Co(II) and Ni(II) with 2-Ethylhexyl Phosphoric Acid Mono-2-Ethylhexyl Ester
by Guijiang Li and Wenze Xu
Separations 2024, 11(4), 116; https://doi.org/10.3390/separations11040116 - 12 Apr 2024
Viewed by 543
Abstract
The escalating demand for cobalt in modern industry necessitates the recycling or extraction of this resource for sustainable development. Despite the abundance of lignin in nature, its utilization remains low, highlighting the need to enhance its value-added potential. This study focuses on the [...] Read more.
The escalating demand for cobalt in modern industry necessitates the recycling or extraction of this resource for sustainable development. Despite the abundance of lignin in nature, its utilization remains low, highlighting the need to enhance its value-added potential. This study focuses on the synthesis of quaternary ammonium lignin (QAL) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (P507) as ionic liquid (QP–IL) compounds for the extraction of metal ions. A comparison of the extraction behavior of Co(II) and Ni(II) from chloride solution between QP–IL and P507 revealed varying extraction ratios under different conditions, with QP–IL demonstrating a higher cobalt extractability than P507. Furthermore, under identical conditions, QP–IL exhibited superior Co/Ni separation performance (βCo/Ni) compared to P507. Ultimately, QP–IL proved to be more effective than P507 in separating cobalt from mixed solutions. Full article
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17 pages, 2725 KiB  
Article
An Evaluation of Microfiltration and Ultrafiltration Pretreatment on the Performance of Reverse Osmosis for Recycling Poultry Slaughterhouse Wastewater
by Faryal Fatima, Sana Fatima, Hongbo Du and Raghava Rao Kommalapati
Separations 2024, 11(4), 115; https://doi.org/10.3390/separations11040115 - 8 Apr 2024
Viewed by 872
Abstract
To implement sustainable water resource management, the industries that produce a huge amount of wastewater are aiming to recycle wastewater. Reverse osmosis (RO) is an advanced membrane process that can produce potable water from wastewater. However, the presence of diverse pollutants in the [...] Read more.
To implement sustainable water resource management, the industries that produce a huge amount of wastewater are aiming to recycle wastewater. Reverse osmosis (RO) is an advanced membrane process that can produce potable water from wastewater. However, the presence of diverse pollutants in the wastewater necessitates effective pretreatment to ensure successful RO implementation. This study evaluated the efficiency of microfiltration (MF) and ultrafiltration (UF) as two pretreatment methods prior to RO, i.e., MF-RO and UF-RO, for recycling poultry slaughterhouse wastewater (PSWW). The direct treatment of PSWW with RO (direct RO) was also considered for comparison. In this study, membrane technology serves as a post treatment for PSWW, which was conventionally treated at Sanderson Farm. The results demonstrated that all of the processes, including MF-RO, UF-RO, and direct RO treatment of PSWW, rejected 100% of total phosphorus (TP), over 91.2% of chemical oxygen demand (COD), and 87% of total solids (TSs). Total nitrogen (TN) levels were reduced to 5 mg/L for MF-RO, 4 mg/L for UF-RO, and 9 mg/L for direct RO. In addition, the pretreatment of PSWW with MF and UF increased RO flux from 46.8 L/m2 h to 51 L/m2 h, an increase of approximately 9%. The product water obtained after MF-RO, UF-RO, and direct RO meets the required potable water quality standards for recycling PSWW in the poultry industry. A cost analysis demonstrated that MF-RO was the most economical option among membrane processes, primarily due to MF operating at a lower pressure and having a high water recovery ratio. In contrast, the cost of using RO without MF and UF pretreatments was approximately 2.6 times higher because of cleaning and maintenance expenses related to fouling. This study concluded that MF-RO is a preferable option for recycling PSWW. This pretreatment method would significantly contribute to environmental sustainability by reusing well-treated PSWW for industrial poultry purposes while maintaining cost efficiency. Full article
(This article belongs to the Section Purification Technology)
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14 pages, 1953 KiB  
Article
Isolation and Identification of Bitter Compounds in Ginseng (Panax ginseng C. A. Mey.) Based on Preparative High Performance Liquid Chromatography, UPLC-Q-TOF/MS and Electronic Tongue
by Yang Chen, Ziwei Liao, Zhe Wang, Wanyin Shi and Jian Xu
Separations 2024, 11(4), 114; https://doi.org/10.3390/separations11040114 - 7 Apr 2024
Viewed by 667
Abstract
As a traditional Chinese medicinal herb, ginseng (Panax ginseng C. A. Mey.) is commonly used to treat common diseases, for example, esophageal cancer and myasthenia gravis. Furthermore, ginseng is also processed into a functional food additive that is utilized to improve the [...] Read more.
As a traditional Chinese medicinal herb, ginseng (Panax ginseng C. A. Mey.) is commonly used to treat common diseases, for example, esophageal cancer and myasthenia gravis. Furthermore, ginseng is also processed into a functional food additive that is utilized to improve the freshness of chicken soup and make health wine. Unfortunately, ginseng (Panax ginseng C. A. Mey.) has already shown a noticeable bitterness during its application process. In this research, the bitter substances in ginseng (Panax ginseng C. A. Mey.) after two common preparation processes (water extraction and ethanol extraction) were separated, purified and identified by preparative high performance liquid chromatography (prep-HPLC), high performance liquid chromatography with diode array detector (HPLC-DAD), ultra-performance liquid chromatography coupled with high-resolution quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) and an electronic tongue. The results indicated that compared with the other four bitter compounds, the ginsenoside Rb1 had the highest bitterness value, followed by 20(S)-ginsenoside Rg2, ginsenoside Rg1, ginsenoside Rf and ginsenoside Rb3. Upon the evaluation of results to reduce the bitterness of ginseng extract, we found that the composite embedding system of chitosan adsorption in the ginseng carrageenan gel microsphere (K/MC/MCG) could effectively reduce the bitterness. Full article
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16 pages, 2917 KiB  
Article
A Robust and Reliable UPLC Method for the Simultaneous Quantification of Rosuvastatin Calcium, Glibenclamide, and Candesartan Cilexetil
by Mohamed Abbas Ibrahim, Abdelrahman Y. Sherif, Doaa Alshora and Badr Alsaadi
Separations 2024, 11(4), 113; https://doi.org/10.3390/separations11040113 - 7 Apr 2024
Viewed by 600
Abstract
Metabolic syndrome is an associated condition that occurs together and increases the risk of heart disease and diabetes. These conditions include high blood pressure, high blood sugar, and high body mass index (BMI) in terms of cholesterol and triglyceride levels. Most of the [...] Read more.
Metabolic syndrome is an associated condition that occurs together and increases the risk of heart disease and diabetes. These conditions include high blood pressure, high blood sugar, and high body mass index (BMI) in terms of cholesterol and triglyceride levels. Most of the elderly population may administer three drugs to control the above conditions. Therefore, this study aims to develop an analytical assay for the precise analysis of three components and to formulate a Self-Nanoemulsifying Drug-Delivery System (SNEDDS) loaded with three drugs: Rosuvastatin Calcium (RC; antilipidemic), Glibenclamide (GB; antidiabetic), and Candesartan Cilexetil (CC; antihypertensive). A design of the experiment was developed at a level of 32, and the influence of column temperature and flow rate was studied in terms of retention time, peak area, peak asymmetry, and resolution. The assay was subjected to several studies to ensure its validation. Under the optimized conditions—column temperature at 50 °C and flow rate at 0.25 mL/min—the three drugs, RC, GB, and CC, are separated. Their retention times are 0.840, 1.800, and 5.803 min, respectively. The assay was valid in terms of linearity, accuracy, and precision. Moreover, the developed assay shows a good tolerance against any change in the condition. The assay was tested also to separate the drugs in a pharmaceutical formulation as SNEDDs. The assay successfully separates the drug with a good resolution. Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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15 pages, 4439 KiB  
Article
Enhanced Photocatalytic and Filtration Performance of TiO2-Ag Composite-Coated Membrane Used for the Separation of Oil Emulsions
by Ákos Ferenc Fazekas, Tamás Gyulavári, Áron Ágoston, László Janovák, Judit Kopniczky, Zsuzsanna László and Gábor Veréb
Separations 2024, 11(4), 112; https://doi.org/10.3390/separations11040112 - 5 Apr 2024
Viewed by 717
Abstract
Polyvinylidene fluoride (PVDF) membranes were coated with TiO2 and TiO2-Ag to enhance their efficiency for oil-in-water emulsion separation. The photocatalytic activities of the two modified membranes and their filtration performances were compared in detail. The significantly enhanced photocatalytic activity of [...] Read more.
Polyvinylidene fluoride (PVDF) membranes were coated with TiO2 and TiO2-Ag to enhance their efficiency for oil-in-water emulsion separation. The photocatalytic activities of the two modified membranes and their filtration performances were compared in detail. The significantly enhanced photocatalytic activity of the TiO2-Ag composite was proved using a methyl orange (MO) solution (c = 10−5 M) and a crude oil emulsion (c = 50 mg·L−1). The TiO2-Ag-coated membrane reduced the MO concentration by 87%, whereas the TiO2-modified membrane reached only a 46% decomposition. The photocatalytic reduction in the chemical oxygen demand of the emulsion was also ~50% higher using the TiO2-Ag-coated membrane compared to that of the TiO2-coated membrane. The photoluminescence measurements demonstrated a reduced electron/hole recombination, achieved by the Ag nanoparticle addition (TiO2-Ag), which also explained the enhanced photocatalytic activity. A significant improvement in the oil separation performance with the TiO2-Ag-coated membrane was also demonstrated: a substantial increase in the flux and flux recovery ratio (up to 92.4%) was achieved, together with a notable reduction in the flux decay ratio and the irreversible filtration resistance. Furthermore, the purification efficiency was also enhanced (achieving 98.5% and 99.9% COD and turbidity reductions, respectively). Contact angle, zeta potential, scanning electron microscopy (SEM), and atomic force microscopy (AFM) measurements were carried out to explain the results. SEM and AFM images revealed that on the TiO2-Ag-coated membrane, a less aggregated, more continuous, homogeneous, and smoother nanolayer was formed due to the ~50% more negative zeta potential of the TiO2-Ag nanocomposite compared to that of the TiO2. In summary, via Ag addition, a sufficiently hydrophilic, beneficially negatively charged, and homogeneous TiO2-Ag-coated PVDF membrane surface was achieved, which resulted in the presented advantageous filtration properties beyond the photocatalytic activity enhancement. Full article
(This article belongs to the Special Issue Advanced Oil–Water Separation Technology)
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14 pages, 4786 KiB  
Article
Optimizing Chromatographic Separation with Redosing: Effects on Separation Efficiency of a Model System in Centrifugal Partition Chromatography
by Felix Buthmann, Jan Hohlmann, Mareen Neuwald and Gerhard Schembecker
Separations 2024, 11(4), 111; https://doi.org/10.3390/separations11040111 - 3 Apr 2024
Viewed by 646
Abstract
This study investigates and optimizes chromatographic separation in a Centrifugal Partition Chromatograph. Therefore, a model system is separated in a single-disc rotor. The occurring loss of the stationary phase lowers the separation efficiency over time. We introduced a new mode of operation, called [...] Read more.
This study investigates and optimizes chromatographic separation in a Centrifugal Partition Chromatograph. Therefore, a model system is separated in a single-disc rotor. The occurring loss of the stationary phase lowers the separation efficiency over time. We introduced a new mode of operation, called the redosing of the stationary phase, to counteract this hydrodynamic phenomenon. Experiments with redosing at an optimized operating point demonstrate almost constant separation performance over 12 h, reducing solvent consumption by 45% and increasing chromatographic resolution by 37%. The improvement in retention by 69% contributes to this enhancement. Accordingly, reference experiments without redosing were conducted as a benchmark, highlighting the automated mode’s benefits, as mentioned. Full article
(This article belongs to the Section Chromatographic Separations)
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12 pages, 5211 KiB  
Article
Preparation of Polysilsesquioxane-Based CO2 Separation Membranes with Thermally Degradable Succinic Anhydride and Urea Units
by Katsuhiro Horata, Tsubasa Yoshio, Ryuto Miyazaki, Yohei Adachi, Masakoto Kanezashi, Toshinori Tsuru and Joji Ohshita
Separations 2024, 11(4), 110; https://doi.org/10.3390/separations11040110 - 2 Apr 2024
Viewed by 770
Abstract
New polysilsesquioxane (PSQ)-based CO2 separation membranes with succinic anhydride and monoalkylurea units as thermally degradable CO2-philic units were prepared by the copolymerization of a 1:1 mixture of [3-(triethoxysilyl)propyl]succinic anhydride (TESPS) or [3-(triethoxysilyl)propyl]urea (TESPU) and bis(triethoxysilyl)ethane (BTESE). The succinic anhydride and [...] Read more.
New polysilsesquioxane (PSQ)-based CO2 separation membranes with succinic anhydride and monoalkylurea units as thermally degradable CO2-philic units were prepared by the copolymerization of a 1:1 mixture of [3-(triethoxysilyl)propyl]succinic anhydride (TESPS) or [3-(triethoxysilyl)propyl]urea (TESPU) and bis(triethoxysilyl)ethane (BTESE). The succinic anhydride and monoalkylurea units underwent thermal degradation to form ester and dialkylurea units, respectively, with the liberation of small molecules (e.g., CO2 and NH3) under N2 atmosphere. The effects of thermal degradation on the performance of the obtained membranes were investigated. The TESPS-BTESE- and TESPU-BTESE-based membranes calcined at 250 °C and 200 °C exhibited good CO2/N2 permselectivities of 20.2 and 14.4, respectively, with CO2 permeances of 7.7 × 10−8 and 7.9 × 10−8 mol m−2·s−1·Pa−1, respectively. When the membranes were further calcined at elevated temperatures of 350 °C and 300 °C, respectively, to promote the thermal degradation of the organic units, the CO2 permeances increased to 1.3 × 10−7 and 1.2 × 10−6 mol m−2·s−1·Pa−1 (3.9 × 102 and 3.6 × 103 GPU), although the CO2/N2 permselectivities decreased to 19.5 and 8.4, respectively. These data indicate that the controlled thermal degradation of the organic units provides a new methodology for possible tuning of the CO2 separation performance of PSQ membranes. Full article
(This article belongs to the Special Issue Preparation of Membranes and Their Application in Separation)
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13 pages, 3922 KiB  
Article
Modulating Interfacial Charge Transfer Behavior through the Construction of a Hetero-Interface for Efficient Photoelectrochemical Water Splitting
by Li Xu, Jingjing Quan, Li Xu, Meihua Li, Chenglong Li, Saqib Mujtaba, Xingming Ning, Pei Chen, Qiang Weng, Zhongwei An and Xinbing Chen
Separations 2024, 11(4), 109; https://doi.org/10.3390/separations11040109 - 1 Apr 2024
Viewed by 710
Abstract
Surface-coupled transition metal oxyhydroxide (TMOOH) on semiconductor (SC)-based photoanodes are effective strategies for improving photoelectrochemical (PEC) performance. However, there is a substantial difference between the current density and theoretical value due to the inevitable interfacial charge recombination of SC/TMOOH. Here, we employ BiVO [...] Read more.
Surface-coupled transition metal oxyhydroxide (TMOOH) on semiconductor (SC)-based photoanodes are effective strategies for improving photoelectrochemical (PEC) performance. However, there is a substantial difference between the current density and theoretical value due to the inevitable interfacial charge recombination of SC/TMOOH. Here, we employ BiVO4/FeNiOOH as a model, constructing the BiVO4/MnOx/CoOx/FeNiOOH integrated system by introducing a novel hetero-interface regulation unit, i.e., MnOx/CoOx. As expected, the optimized integrated system demonstrates a photocurrent density as high as 5.0 mA/cm2 at 1.23 V versus the reversible hydrogen electrode (RHE) under 1 sun AM 1.5G illumination, accompanied by 12-h stability. The detailed electrochemical analysis and intensity modulated photocurrent spectroscopy (IMPS) have confirmed that the high PEC performance mainly originates from the hetero-interface structure, which not only suppresses the interfacial charge recombination by accelerating the photogenerated hole transfer kinetics from BiVO4 to FeNiOOH but promotes the kinetics of surface oxygen evolution reaction (OER). Notably, these findings can also be extended to other structures (CeOx/CoOx), reflecting its universality. This finding has provided a new insight into the highly efficient solar energy conversion in the SC/TMOOH system. Full article
(This article belongs to the Special Issue Adsorption and Solar-Powered Decomposition for Removing Pollutants)
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18 pages, 3870 KiB  
Article
Carbon–Carbon Composite Membranes Derived from Small-Molecule-Compatibilized Immiscible PBI/6FDA-DAM-DABA Polymer Blends
by Chamaal Karunaweera, Nimanka P. Panapitiya, Samitha Panangala, Edson V. Perez, Inga H. Musselman, Kenneth J. Balkus, Jr. and John P. Ferraris
Separations 2024, 11(4), 108; https://doi.org/10.3390/separations11040108 - 1 Apr 2024
Viewed by 814
Abstract
The use of immiscible polymer blends in gas separations is limited due to uncontrollable phase separation. In contrast, compatibilized immiscible polymer blends can be used as precursors with controlled morphologies that allow for a unique pore architecture. Herein, an immiscible polymer blend (1:1) [...] Read more.
The use of immiscible polymer blends in gas separations is limited due to uncontrollable phase separation. In contrast, compatibilized immiscible polymer blends can be used as precursors with controlled morphologies that allow for a unique pore architecture. Herein, an immiscible polymer blend (1:1) comprising polybenzimidazole (PBI) and the copolyimide 6FDA-DAM:DABA [3:2], derived from reacting 4,4-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with 2,4,6-trimethyl-1,3-phenylenediamine (DAM) and 3,5-diaminobenzoic acid (DABA), were combined with durene diamine as a compatibilizer. The compatibilizer helped reduce the 6FDD domain sizes from 5.6 µm down to 0.77 µm and induced a more even 6FDA distribution and the formation of continuous thin-selective PBI layers. The carbon–carbon composite membranes derived from the compatibilized immiscible polymer blends showed a 3-fold increase in both H2 permeability and H2/CO2 selectivity compared to the membranes derived from non-compatibilized polymer blends. The H2 permeability of the compatibilized immiscible polymer blends increased from 3.6 to 27 Barrer, and their H2/CO2 selectivity increased from 7.2 to 20. The graphitic domain size of the carbon–carbon composite membranes derived from the polymer blends also increased from 6.3 nm for the non-compatibilized blend to 10.0 nm for the compatibilized blend. Full article
(This article belongs to the Section Materials in Separation Science)
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14 pages, 5548 KiB  
Article
Changes in the Serum and Tissue Levels of Free and Conjugated Sialic Acids, Neu5Ac, Neu5Gc, and KDN in Mice after the Oral Administration of Edible Bird’s Nests: An LC–MS/MS Quantitative Analysis
by Meng-Hua Wang, Zhi-Fan Wang, Man Yuan, Chun-Guo Yang, Dong-Liang Wang and Shu-Qi Wang
Separations 2024, 11(4), 107; https://doi.org/10.3390/separations11040107 - 1 Apr 2024
Viewed by 786
Abstract
Edible bird’s nests have a variety of biological activities, the main components of which are sialic acids. Sialic acids are a group of nine-carbon N-acetylated derivatives of neuraminic acid containing a keto group at position C2 and play important roles in many biological [...] Read more.
Edible bird’s nests have a variety of biological activities, the main components of which are sialic acids. Sialic acids are a group of nine-carbon N-acetylated derivatives of neuraminic acid containing a keto group at position C2 and play important roles in many biological processes. To verify whether the oral administration of edible bird’s nests would change the content and distribution of sialic acid components in vivo, a liquid chromatography–mass spectrometry method for the quantitative analysis of sialic acid levels in serum and tissues was developed. In the negative ion mode, the mobile phases consist of 0.1% formic acid in water (A) and acetonitrile (v/v) (B). Isocratic elution was performed with 60% B for 0−15 min. The chromatographic separation was performed on a Morphling HILIC Amide column (2.1 mm × 150 mm, 5 μm) at a flow rate of 0.5 mL min−1. The results showed that the correlation coefficients of the typical calibration curves were all higher than 0.995, exhibiting good linearity. The levels of free and conjugated forms of N-glycolylneuraminic acid (Neu5Gc), N-acetylneuraminic acid (Neu5Ac), and 2-keto-3-deoxy-D-glycero-D-galactonononic acid (KDN) in the serum and different tissues were simultaneously detected after the oral administration of the edible bird’s nests at a daily dose of 300 and 700 mg Kg−1 for seven days in mice. Our study found that the oral administration of edible bird’s nests can significantly increase the concentration of total sialic acids (Neu5Gc + Neu5Ac + KDN) in serum and spleen and lungs tissues, which may be related to the anti-inflammatory and immune function of edible bird’s nest, but further studies are needed to verify this. Neu5Ac was the dominant sialic acid in brain tissue, and Neu5Gc was the dominant sialic acid in serum and other tissues, including heart, liver, spleen, lungs, and kidney. Moreover, we found that the forms of Neu5Ac and Neu5Gc were mainly conjugated in all groups except liver tissue. In conclusion, the method we established had good linearity and accuracy; it allowed the analytes to be effectively separated from the matrix and endogenous substances in serum or tissues, so it could effectively detect the distribution and concentration of free and conjugated forms of sialic acids in serum and tissues, which was beneficial to the research and exploitation of edible bird’s nests and sialic acids. Full article
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15 pages, 4955 KiB  
Article
Comparison of the Efficiency of Deep Eutectic and Organic Solvents in the Extraction of Phytochemicals from Cannabis sativa L.
by Getrude G. Kanyairita, Desmond G. Mortley, Melissa Boersma and Willard E. Collier
Separations 2024, 11(4), 106; https://doi.org/10.3390/separations11040106 - 30 Mar 2024
Viewed by 1016
Abstract
Industrial hemp (Cannabis sativa L.) is an attractive candidate for sustainable pest management due to its abundance of bioactive compounds with potential pesticidal properties. Solvent choice has a significant impact on the extraction efficiency of bioactive compounds. Deep Eutectic Solvents (DESs) are [...] Read more.
Industrial hemp (Cannabis sativa L.) is an attractive candidate for sustainable pest management due to its abundance of bioactive compounds with potential pesticidal properties. Solvent choice has a significant impact on the extraction efficiency of bioactive compounds. Deep Eutectic Solvents (DESs) are gaining popularity in extraction because they are safe and environmentally friendly, making them viable alternatives to organic solvents (OSs). This research first compared the extraction efficiency of OSs in the extraction of phytochemicals from the infloresences of two hemp varieties, Citrus and Cherry Dwarf. Inflorescences were extracted using three OSs, ethanol, ethyl acetate, and hexane. The highest level of cannabidiol (CBD; 0.69%) was extracted from Cherry Dwarf using ethanol, while the level of delta-9 tetrahydrocannabinol THC (0.19%) was essentially the same in both. Therefore, Cherry Dwarf was selected to compare the extraction efficiency of DESs with OSs. The DESs were choline chloride/ethylene glycol, citric acid/ethylene glycol, menthol/lauric acid, choline chloride/urea, and choline chloride/glycerol. In the targeted analysis, choline chloride/ethylene glycol extracted the highest amount of CBD (0.87%) followed by choline chloride/urea (0.78%). As some DESs outperformed ethanol, the popular solvent for extracting cannabinoids, DESs are viable candidates for replacement of organic solvents. Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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13 pages, 1920 KiB  
Article
Structural Characterization and Immunological Activity of Polysaccharide Degradation Products from Phlebopus portentosus
by Dan Yu, Xiaoming Cai, Shuo Wang, Yi Li, Yuguang Du, Zhuo A. Wang, Siming Jiao and Zhenquan Yang
Separations 2024, 11(4), 105; https://doi.org/10.3390/separations11040105 - 30 Mar 2024
Viewed by 852
Abstract
Phlebopus portentosus is an edible and medicinal mushroom with a delicious taste and high nutritional value. The oligosaccharides derived from P. portentosus may be the material basis for its biological activity. The degradation of polysaccharide and the maintenance of its activity after degradation [...] Read more.
Phlebopus portentosus is an edible and medicinal mushroom with a delicious taste and high nutritional value. The oligosaccharides derived from P. portentosus may be the material basis for its biological activity. The degradation of polysaccharide and the maintenance of its activity after degradation are key steps in related research. This study applied an acid degradation method to prepare P. portentosus refined polysaccharide (PPRP) with a smaller molecular weight, and the optimal hydrolysis conditions determined were a temperature of 80 °C, an acid concentration of 2 mol/L, and a hydrolysis time of 2 h. The polysaccharide structure and immune activity were then further investigated. The results showed that the PPRP comprised two fractions with approximate weights of 61,600 Da and 5500 Da. The monosaccharide composition of PPRP was mannose, rhamnose, glucose, and galactose, with a molar ratio of 1.00: 22.24: 2.93: 1.03. The major functional groups included O-H, C-H, C-O, and C-O-C. The glycosidic bond types were mainly α- and β-glycosidic bonds. Cell experiments demonstrated that PPRP could significantly increase the proliferation of macrophages and enhance the cytotoxicity of NK cells. Moreover, PPRP also significantly promoted the proliferation of B lymphocytes and T lymphocytes, especially at a concentration of 200 μg/mL. This study furnishes scientific evidence underlining the significant potential of PPRP in immune activity, thereby serving as a material basis and scientific bedrock for further investigations into the mechanism of P. portentosus oligosaccharide activity. Full article
(This article belongs to the Special Issue Research Progress for Isolation of Plant Active Compounds)
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14 pages, 3956 KiB  
Article
Quality Evaluation and Identification of Phyllanthi fructus (Yuganzi) Based on the Spectrum-Effect Relationship
by Weiwei Zhou, Bencheng Wu, Ling Liu, Jun Li, Dongdong Shi and Xiumei Li
Separations 2024, 11(4), 104; https://doi.org/10.3390/separations11040104 - 29 Mar 2024
Viewed by 756
Abstract
To establish a quality evaluation and identification method for Phyllanthi fructus (Yuganzi), the spectrum-effect relationship was explored. A high-performance liquid chromatography (HPLC) fingerprint was established using ultraviolet spectrophotometry, and the in vitro antioxidant activity was determined using a total antioxidant capacity assay kit. [...] Read more.
To establish a quality evaluation and identification method for Phyllanthi fructus (Yuganzi), the spectrum-effect relationship was explored. A high-performance liquid chromatography (HPLC) fingerprint was established using ultraviolet spectrophotometry, and the in vitro antioxidant activity was determined using a total antioxidant capacity assay kit. Similarity analysis, hierarchical cluster analysis (HCA), and partial least squares regression (PLSR) were performed to establish the spectrum-effect relationships. Thirteen batches of Yuganzi were collected for testing. The results revealed that the optimal chromatographic conditions for the HPLC fingerprint were as follows: the mobile phase consisted of 0.1% phosphoric acid solution (A) and acetonitrile (B), the detection wavelength was 214 nm, the column temperature was 30 °C, and the flow rate was 0.8 mL/min. Among the batches of samples, the similarity values of 10 samples (S1–S10) from Yunnan were larger than 0.995; the similarity values of 3 samples (S11–S13) from India, Gaoligong Mountain, and Fujian were less than or equal to 0.986. Furthermore, nineteen characteristic peaks of Yuganzi were calibrated using fingerprint evaluation software. The study on the spectrum-effect relationship further revealed that compounds corresponding to peaks 5 and 8 were potentially key ingredients for the quality evaluation and identification of Yuganzi, closely related to the stable antioxidant activities of Yuganzi. The spectrum-effect relationship is an agile and efficient approach that can ensure the intra-assay stability of Yuganzi from same region and identify Yuganzi from different regions. Compounds with antioxidant activity can be identified as quality markers for Yuganzi. Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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13 pages, 2676 KiB  
Article
Rapid Determination of Taraxacum kok-saghyz Rubber Content Using a Pyrolyzer Hyphenated with a Miniaturized Mass Spectrometer
by Shunkai Gao, Minmin Guo, Jiaqi Gao, Zejian Huang, Min Gan, Jichuan Zhang and Yiyang Dong
Separations 2024, 11(4), 103; https://doi.org/10.3390/separations11040103 - 29 Mar 2024
Viewed by 700
Abstract
Taraxacum kok-saghyz (TKS), a rubber-producing plant with excellent potential, emerges as a viable substitute for rubber tree (Hevea brasiliensis). While natural rubber is a desirable material, conventional techniques for assessing rubber content have faced challenges in meeting practical production requirements. To [...] Read more.
Taraxacum kok-saghyz (TKS), a rubber-producing plant with excellent potential, emerges as a viable substitute for rubber tree (Hevea brasiliensis). While natural rubber is a desirable material, conventional techniques for assessing rubber content have faced challenges in meeting practical production requirements. To address this issue, we have developed a pyrolysis–mass spectrometry (PY-MS) instrument for the quantitative evaluation of natural rubber (NR) content in rubber-producing plants. The derived standard curve equation, established for the detection of TKS dry weight through external standard calibration, demonstrates a correlation coefficient (R2) surpassing 0.99. The method exhibits commendable recovery rates (93.27–107.83%), relative standard deviations (RSD ≤ 3.93%), and a swift analysis time of merely 10 min per sample, thereby enabling accurate and efficient quantification of NR dry weight. Additionally, the PY-MS system we designed can be modified for vehicular use, enabling on-site, in situ analysis, and it provides substantial support for TKS breeding and propagation efforts. This approach possesses significant potential for extensive utilization in the assessment of rubber content in rubber-producing plants other than TKS. The integration of pyrolysis–mass spectrometry for the identification of polymers with high molecular weight offers a valuable pathway for the examination of diverse polymers. Full article
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16 pages, 4537 KiB  
Article
Variations in Essential Oil Biological Activities of Female Cones at Different Developmental Stages from Azorean Cryptomeria japonica (Thunb. ex L.f.) D. Don (Cupressaceae)
by Alexandre Janeiro, Ana Lima, Filipe Arruda, Tanner Wortham, Tânia Rodrigues, José Baptista and Elisabete Lima
Separations 2024, 11(4), 102; https://doi.org/10.3390/separations11040102 - 29 Mar 2024
Viewed by 979
Abstract
In the Azores Archipelago, Cryptomeria japonica is, currently, the most cultivated forestry tree for timber production, landscaping, and gardening, generating large amounts of foliage waste that is used for local essential oils (EOs) production. However, the existing literature on the biological potential of [...] Read more.
In the Azores Archipelago, Cryptomeria japonica is, currently, the most cultivated forestry tree for timber production, landscaping, and gardening, generating large amounts of foliage waste that is used for local essential oils (EOs) production. However, the existing literature on the biological potential of EOs from different C. japonica foliage parts, such as female cones (FC), remains limited. Thus, in the present study, EOs extracted by hydrodistillation from Azorean C. japonica immature and mature FC (IFC and MFC), as well as some major EO components, were screened for their: (i) antioxidant capacity, evaluated by DPPH free-radical-scavenging activity (FRSA) and β-carotene-linoleic acid bleaching activity (BCBA), (ii) antimicrobial activities, assessed by the disc diffusion method against eight bacteria and one fungus, and (iii) toxicity against Artemia salina. Among both FC EO samples, the IFC EO exhibited the best DPPH–FRSA, BCBA, and growth inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Penicillium italicum, as well as a slightly increased toxic potential, due to their differential compositions, as assessed by GC–MS analysis. Thus, the FC’s maturation process decreased their EOs’ bioactivities. In conclusion, this finding could help in determining the optimal developmental stage for enhancing the antioxidant and antimicrobial compounds content in FC EOs. In turn, this contributes to increasing the commercial potential of C. japonica’s EO industry. Full article
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16 pages, 703 KiB  
Article
Effects of Abelmoschus esculentus Extracts and Fractions on Embryos and Adult Individuals of Biomphalaria glabrata (Say, 1818) and on Schistosoma mansoni Cercariae
by João Claudio Vitoria Atico Leite, Leonardo da Silva Rangel, Keyla Nunes Farias Gomes, Ricardo Diego Duarte Galhardo de Albuquerque, José Augusto Albuquerque dos Santos and Robson Xavier Faria
Separations 2024, 11(4), 99; https://doi.org/10.3390/separations11040099 - 28 Mar 2024
Viewed by 911
Abstract
Schistosomiasis is a neglected tropical disease caused by parasitic worms of the genus Schistosoma. In Brazil, there are reports of infection by the Schistosoma mansoni species, which has the Biomphalaria glabrata snail as one of its intermediate hosts. The present work aimed to [...] Read more.
Schistosomiasis is a neglected tropical disease caused by parasitic worms of the genus Schistosoma. In Brazil, there are reports of infection by the Schistosoma mansoni species, which has the Biomphalaria glabrata snail as one of its intermediate hosts. The present work aimed to test the effects of different Abelmoschus esculentus seed extracts and fractions on adults and embryos of B. glabrata and S. mansoni cercariae. A total of four crude extracts and thirteen fractions with different organic solvents were used for the bioassays. The extracts were analyzed using high-performance liquid chromatography coupled to mass spectrometry. Molluscicidal activity was assessed in 24-well plates, after which the LC50 and LC90 were calculated. Assays with B. glabrata embryos and S. mansoni cercariae were also performed. These findings indicate the presence of flavanoids in the hexane, ethyl acetate, and ethanol crude extracts. For the molluscicidal activity assays, eight fractions had an LC90 value less than that recommended by the WHO. The methanol fraction of the dichloromethane extract (FrMeOH EDM) had the most promising results, with an LC90 of 37.15 mg/L and 100% mortality in embryos of B. glabrata and cercariae. FrMeOH, EDM, and other fractions are possible candidates for new drugs for the combat of schistosomiasis. Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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15 pages, 1904 KiB  
Article
Recovery of Omega-3-Rich Lipids: Toward the Sustainable Valorization of Sea-Bass Industry Side Streams
by Ioanna Semenoglou, Maria Katsouli, Maria Giannakourou and Petros Taoukis
Separations 2024, 11(4), 101; https://doi.org/10.3390/separations11040101 - 28 Mar 2024
Viewed by 815
Abstract
This study pertains to the selection of the appropriate process parameters of lipid extraction aimed at the valorization of sea-bass gutting and filleting side stream biomass. A comparative kinetic study between an environmentally friendly polar (ethanol) and a conventional non-polar solvent (hexane) was [...] Read more.
This study pertains to the selection of the appropriate process parameters of lipid extraction aimed at the valorization of sea-bass gutting and filleting side stream biomass. A comparative kinetic study between an environmentally friendly polar (ethanol) and a conventional non-polar solvent (hexane) was implemented to determine the effect of temperature, solvent to solid ratio and time, providing insights in terms of the yield recovery and quality of omega-3 fatty acids. Maximum recovery yield (43.8 and 34.0 g/100 g of dried gutting and filleting by-products, respectively) was achieved within 10 min. In gutting by-products, ethanol achieved full lipid recovery at 35 °C and a 50:1 ratio, while for hexane, the maximum yield was 83%. In the case of filleting side-streams, hexane achieved exhaustive recovery at a 50:1 ratio and 20 °C compared with ethanol, where a higher temperature (50 °C) was needed for exhaustive recovery to be achieved. Differences were attributed to the diverse fatty acid profiles among the two by-products, with 27.3% and 40.8% polyunsaturated fatty acids in viscera and fish frames, respectively. All extracts at 20 °C and 35 °C remained below the oxidation limit set by the Codex Alimentarius Commission (peroxide value < 5 meqO2/kgoil; p-anisidine value < 20). Therefore, green solvents could assist conventional extraction, combining high efficiency and an improved environmental impact. Full article
(This article belongs to the Section Analysis of Natural Products and Pharmaceuticals)
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