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Keywords = semi-preparative fractionation

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40 pages, 5707 KB  
Review
Graph Representation Learning for Battery Energy Systems in Few-Shot Scenarios: Methods, Challenges and Outlook
by Xinyue Zhang and Shunli Wang
Batteries 2026, 12(1), 11; https://doi.org/10.3390/batteries12010011 - 26 Dec 2025
Viewed by 466
Abstract
Graph representation learning (GRL) has emerged as a unifying paradigm for modeling the relational and heterogeneous nature of battery energy storage systems (BESS), yet a systematic synthesis focused on data-scarce (few-shot) battery scenarios is still lacking. Graph representation learning offers a natural way [...] Read more.
Graph representation learning (GRL) has emerged as a unifying paradigm for modeling the relational and heterogeneous nature of battery energy storage systems (BESS), yet a systematic synthesis focused on data-scarce (few-shot) battery scenarios is still lacking. Graph representation learning offers a natural way to describe the structure and interaction of battery cells, modules and packs. At the same time, battery applications often suffer from very limited labeled data, especially for new chemistries, extreme operating conditions and second-life use. This review analyzes how graph representation learning can be combined with few-shot learning to support key battery management tasks under such data-scarce conditions. We first introduce the basic ideas of graph representation learning, including models based on neighborhood aggregation, contrastive learning, autoencoders and transfer learning, and discuss typical data, model and algorithm challenges in few-shot scenarios. We then connect these methods to battery state estimation problems, covering state of charge, state of health, remaining useful life and capacity. Particular attention is given to approaches that use graph neural models, meta-learning, semi-supervised and self-supervised learning, Bayesian deep networks, and federated learning to extract transferable features from early-cycle data, partial charge–discharge curves and large unlabeled field datasets. Reported studies show that, with only a small fraction of labeled samples or a few initial cycles, these methods can achieve state and life prediction errors that are comparable to or better than conventional models trained on full datasets, while also improving robustness and, in some cases, providing uncertainty estimates. Based on this evidence, we summarize the main technical routes for few-shot battery scenarios and identify open problems in data preparation, cross-domain generalization, uncertainty quantification and deployment on real battery management systems. The review concludes with a research outlook, highlighting the need for pack-level graph models, physics-guided and probabilistic learning, and unified benchmarks to advance reliable graph-based few-shot methods for next-generation intelligent battery management. Full article
(This article belongs to the Section Battery Modelling, Simulation, Management and Application)
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14 pages, 1658 KB  
Article
Isolation and In Vitro Activity of Sesquiterpene Lactones from Eremanthus crotonoides as SARS-CoV-2 Protease Inhibitors and Cytotoxic Agents
by Patricia Homobono Brito de Moura, Natalie Giovanna da Rocha Ximenes, Beatriz Bastos Santos, Carla Monteiro Leal, Larissa Esteves Carvalho Constant, Stephany da Silva Costa, Shaft Corrêa Pinto, Michelle Frazao Muzitano, Diego Allonso, Ludger A. Wessjohann and Ivana Correa Ramos Leal
Molecules 2025, 30(20), 4053; https://doi.org/10.3390/molecules30204053 - 11 Oct 2025
Viewed by 674
Abstract
The Jurubatiba Sandbank National Park (PARNA Jurubatiba) is an ecological reserve characterized by harsh environmental conditions, including low rainfall, high sun exposure, and sandy soil. Among its native vegetation, Eremanthus crotonoides stands out for its richness in flavonoids, phenolic compounds, and sesquiterpene lactones. [...] Read more.
The Jurubatiba Sandbank National Park (PARNA Jurubatiba) is an ecological reserve characterized by harsh environmental conditions, including low rainfall, high sun exposure, and sandy soil. Among its native vegetation, Eremanthus crotonoides stands out for its richness in flavonoids, phenolic compounds, and sesquiterpene lactones. The objective of this study was to isolate and quantify sesquiterpene lactones from this species using 1H NMR and to investigate their anti-SARS-CoV-2 potential and cytotoxicity against cancer cells. UPLC-(ESI)-MS/MS analyses enabled metabolite annotation, and semi-preparative HPLC-DAD allowed the isolation of centratherin and goyazensolide, which were identified by 1D and 2D NMR. In vitro assays showed that centratherin at 10 µM concentration reduced the viability of PC-3 and HCT-116 cancer cells by 100%, while goyazensolide had no noteworthy effects. Furthermore, enzymatic inhibition assays on SARS-CoV2 targets revealed that centratherin exhibited a lower apparent IC50 of 12 µM against PLpro, while goyazensolide was more active against 3CLpro, with an IC50 of 71 µM. Notably, the dichloromethane fraction demonstrated promising activity against both enzymes, with IC50 values of 30 µM for PLpro and 11 µM for 3CLpro. This study reports, for the first time, the isolation of goyazensolide from E. crotonoides and highlights the potential of both sesquiterpene lactones as SARS-CoV-2 enzyme inhibitors. In contrast to centratherin, goyazensolide fortunately had almost no cytotoxic effects at inhibition concentration on the cells tested. This shows that anticancer and anti-SARS effects can be separated and should have different SARs, an important prerequisite for further development. Full article
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18 pages, 8882 KB  
Article
Effects of Cooling Rate and Solid Fraction on α-Al Phase Evolution in Rheo-Die Casting: Phase-Field Simulation and Experimental Investigation
by Song Chen, Wangwang Kuang, Jian Feng, Hongmiao Wang, Fan Zhang and Daquan Li
Materials 2025, 18(17), 4169; https://doi.org/10.3390/ma18174169 - 5 Sep 2025
Viewed by 1112
Abstract
This study aims to bridge the critical knowledge gap in understanding the dynamic microstructural evolution during high-solid-fraction semi-solid rheo-die casting process, including slurry preparation (0.1–0.3 K/s) and rheo-die casting (10–150 K/s). A novel phase-field model coupling continuous cooling with explicit nucleation was developed, [...] Read more.
This study aims to bridge the critical knowledge gap in understanding the dynamic microstructural evolution during high-solid-fraction semi-solid rheo-die casting process, including slurry preparation (0.1–0.3 K/s) and rheo-die casting (10–150 K/s). A novel phase-field model coupling continuous cooling with explicit nucleation was developed, enabling the dynamic simulation of continuous solidification microstructure evolution, considering two-stage cooling rate transition characteristics. Integrated the Swirled Enthalpy Equilibration Device (SEED) slurry preparation and graded-cooling mold experiments established variable cooling rate and solid fraction conditions for quantitative analysis of α-Al morphological evolution during rheo-die casting solidification. Through experimental and simulation investigations of the Al-7Si alloy, it is concluded that during Stage I slurry preparation, the primary α1-Al phase coarsened due to Ostwald ripening. In Stage II rheo-die casting, primary α1-Al undergoes continued growth under a moderate cooling rate (15 K/s). Meanwhile, secondary α2-Al formation exhibits a cooling-rate and solid fraction dependence: a high cooling rate (150 K/s) promotes explosive nucleation with the volume fraction decreasing from 4.78% to 0.33% as the solid fraction rises, whereas a mid-cooling rate (15 K/s) substantially suppresses its formation. Mechanistically, a high cooling rate promotes solute trapping, which intensifies constitutional undercooling, thereby elevating both the nucleation and growth driving forces to facilitate the formation of secondary α2-Al, whereas higher solid fractions restrict secondary phase formation by narrowing the solidification windows from 22 °C to 7 °C. Full article
(This article belongs to the Special Issue Microstructure and Defect Simulation during Solidification of Alloys)
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37 pages, 8995 KB  
Article
Process Analysis of Waste Animal Fat Pyrolysis and Fractional Distillation in Semi-Batch Reactors: Influence of Temperature and Reaction Time
by Alex Lopes Valente, Marcelo Figueiredo Massulo Aguiar, Ana Claudia Fonseca Baia, Lauro Henrique Hamoy Guerreiro, Renan Marcelo Pereira Silva, Lucas Sabino do Vale Scaff, Dilson Nazareno Pereira Cardoso, Hugo Fernando Meiguins da Silva, Davi do Socorro Barros Brasil, Neyson Martins Mendonça, Sergio Duvoisin Junior, Douglas Alberto Rocha de Castro, Luiz Eduardo Pizarro Borges, Nélio Teixeira Machado and Lucas Pinto Bernar
Energies 2025, 18(17), 4517; https://doi.org/10.3390/en18174517 - 26 Aug 2025
Viewed by 1922
Abstract
Waste animal fat (WAF) can be converted to distillate fractions similar to petroleum solvents and used as solvents via pyrolysis and fractional distillation. Pyrolysis oil from triglyceride materials presents adequate viscosity and volatility, compared to petroleum fuels, but shows acid values between 60–140 [...] Read more.
Waste animal fat (WAF) can be converted to distillate fractions similar to petroleum solvents and used as solvents via pyrolysis and fractional distillation. Pyrolysis oil from triglyceride materials presents adequate viscosity and volatility, compared to petroleum fuels, but shows acid values between 60–140 mg KOH/g, impeding its direct use as biofuels without considerable purification of its distillates. Fractional distillation can be applied for the purification of bio-oil, but only a few studies accurately describe the process. The purpose of this study was to evaluate the effect of temperature in the conversion of waste animal fat into fuel-like fractions by pyrolysis and fractional distillation in a semi-batch stirred bed reactor (2 L) according to reaction time. Waste animal fat was extracted (rendering) from disposed meat cuts obtained from butcher shops and pyrolyzed in a stainless-steel stirred bed reactor operating in semi-batch mode at 400–500 °C. The obtained liquid fraction was separated according to reaction time. The pyrolysis bio-oil at 400 °C was separated into four distinct fractions (gasoline, kerosene, diesel, and heavy phase) by fractional distillation with reflux. The bio-oil and distillate fractions were analyzed by density, kinematic viscosity, acid value, and chemical composition by gas chromatography coupled to mass spectra (GC-MS). The results show that, for semi-batch reactors with no inert gas flow, higher temperature is associated with low residence time, reducing the conversion of fatty acids to hydrocarbons. The distillate fractions were tested in a common application not sensible to the fatty acid concentration as a diluent in the preparation of diluted asphalt cutback for the priming of base pavements in road construction. Kerosene and diesel fractions can be successfully applied in the preparation of asphalt cutbacks, even with a high acid value. Full article
(This article belongs to the Section A: Sustainable Energy)
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21 pages, 2681 KB  
Article
Metabolites from the Dendrobium Endophyte Pseudomonas protegens CM-YJ44 Alleviate Insulin Resistance in HepG2 Cells via the IRS1/PI3K/Akt/GSK3β/GLUT4 Pathway
by Luqi Qin, Yixia Zhou, Bei Fan, Jiahuan Zheng, Rao Diao, Jiameng Liu and Fengzhong Wang
Pharmaceuticals 2025, 18(6), 817; https://doi.org/10.3390/ph18060817 - 29 May 2025
Cited by 2 | Viewed by 1255 | Correction
Abstract
Background/Objectives: Endophytes can produce bioactive metabolites similar to their host plants. CM-YJ44 (Pseudomonas protegens CHA0, 99.24% similarity), an endophyte from Dendrobium officinale, has not yet validated hypoglycemic potential. This study aimed to evaluate its anti-insulin resistance (IR) activity and metabolite profile. [...] Read more.
Background/Objectives: Endophytes can produce bioactive metabolites similar to their host plants. CM-YJ44 (Pseudomonas protegens CHA0, 99.24% similarity), an endophyte from Dendrobium officinale, has not yet validated hypoglycemic potential. This study aimed to evaluate its anti-insulin resistance (IR) activity and metabolite profile. Methods: The fermentation broth of CM-YJ44 was separated into three fractions (CM-YJ44-1, -2, and -3) using semi-preparative high-performance liquid chromatography (pre-HPLC). An IR HepG2 cell model was constructed to evaluate their glucose uptake capacity. CM-YJ44-3 was further tested for oxidative stress, inflammatory, and insulin signaling pathway activation. Metabolites in CM-YJ44-3 were preliminarily identified using the Q Exactive Focus LC-MS system (QE), and the dendrobine content was quantified by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Molecular docking was performed to predict the binding affinities between dendrobine and target proteins. Results: Among the three fractions, CM-YJ44-3 significantly reduced nitric oxide (NO) and reactive oxygen species (ROS) levels in IR cells, enhanced glycogen synthesis, upregulated the activities of pyruvate kinase (PK) and hexokinase (HK), and suppressed the expression of inflammatory factors. Its mechanism of action was mainly through activation of the IRS1/PI3K/Akt/GSK3β/GLUT4 signaling pathway. QE analysis preliminarily identified 24 metabolites in CM-YJ44-3. Quantitative analysis by UPLC-MS/MS showed that the dendrobine content was 78.73 ± 4.29 ng/mL. Molecular docking results indicated that dendrobine exhibited binding energies below −5 kcal/mol with multiple target proteins involved in this signaling pathway, suggesting it may be a key bioactive component responsible for the anti-IR effect. Conclusions: This study provides the first evidence of hypoglycemic bioactive metabolite production by strain CM-YJ44, indicating its potential as a novel microbial candidate for alleviating IR. Full article
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23 pages, 7244 KB  
Article
Electrospray–Mass Spectrometry-Guided Targeted Isolation of Indole Alkaloids from Leaves of Catharanthus roseus by Using High-Performance Countercurrent Chromatography
by Mahdi Yahyazadeh, Dirk Selmar and Gerold Jerz
Molecules 2025, 30(10), 2115; https://doi.org/10.3390/molecules30102115 - 9 May 2025
Viewed by 1517
Abstract
Electrospray mass spectrometry off-line profiling monitored the recovery of targeted indole alkaloids from a fortified crude extract of Catharanthus roseus (790 mg) using semi-preparative high-performance countercurrent chromatography (HPCCC) fractionation. Visualization of selected single-ion traces projected the HPCCC molecular weight elution profile. Experimental partition-ratio [...] Read more.
Electrospray mass spectrometry off-line profiling monitored the recovery of targeted indole alkaloids from a fortified crude extract of Catharanthus roseus (790 mg) using semi-preparative high-performance countercurrent chromatography (HPCCC) fractionation. Visualization of selected single-ion traces projected the HPCCC molecular weight elution profile. Experimental partition-ratio values KD and peak widths for detected metabolites were determined. Structural characterization of metabolites and co-elution effects were monitored in the scan range m/z 100–2000. In this study, the biphasic solvent system containing n-hexane–n-butanol–water with 0.5% ion-pair reagent trifluoro-acetic acid [1:1:2, v/v/v] was used based on partition ratio KD-value liquid chromatography–electrospray ionization–mass spectrometry (LC-ESI-MS) analysis prediction. The monitoring of target ions resulted in the isolation of six major concentrated indole alkaloids (akuammicine, catharanthine, perivine, vindoline, vindorosine, and 19R-vindolinine), which were fully elucidated by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. Full article
(This article belongs to the Section Natural Products Chemistry)
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17 pages, 3757 KB  
Article
Phytochemical Composition and Skin-Friendly Activities of the Ethyl Acetate Fraction in Ophioglossum vulgatum Linn., an In Vitro Study
by Sihan Feng, Zhiguang Huang, Yichen Cao, Zixuan Huang, Chen Xu, Yibo Zeng, Yuhang Xu, Lijian Zhu and Bin Ding
Pharmaceuticals 2025, 18(3), 345; https://doi.org/10.3390/ph18030345 - 27 Feb 2025
Viewed by 1503
Abstract
Background: Ophioglossum vulgatum Linn. is a medical herb widely distributed in Southwest China. It has been used for the treatment of various diseases, including wounds or dermatitis, since ancient times, but little is known about its pharmacological and pharmaceutical chemistry. Methods: [...] Read more.
Background: Ophioglossum vulgatum Linn. is a medical herb widely distributed in Southwest China. It has been used for the treatment of various diseases, including wounds or dermatitis, since ancient times, but little is known about its pharmacological and pharmaceutical chemistry. Methods: The ethyl acetate fraction of O. vulgatum (OpvE) was prepared with the reflex extraction and fractional extraction method. Its components were detected and identified with the UPLC-Q/TOF-MS system and the SCIEX OS database. The related biological activities and the underlying mechanisms were predicted by computational analysis. HaCaT cells were treated with gradient concentrations of OpvE, and a CCK-8 assay was performed to determine the cell viability. The OpvE-pretreated HaCaT cells were exposed to H2O2 or LPS for antioxidative and anti-inflammatory assessment. DPPH, GSH, SOD, and MDA kits were used to evaluate oxidative stress. A serially diluted microbiota assay and a disc diffusion assay were used to evaluate anti-Staphylococcus aureus activities. The transcription of genes was semi-quantitatively studied by reversed real-time PCR. Protein levels were determined with western blotting. Results: The extract ratio of OpvE was 2.00 ± 0.12% (g/g). A total of 21 ingredients were identified. The computational analysis found that the PI3K/Akt signaling pathway might be a crucial target of OpvE. OpvE (7.5~125 μg/mL) stimulated HaCaT cell proliferation and migration by stimulating the over-expressed collagen type I alpha 1 Chain (COL1A1) and fibronectin 1 (FN1) and upregulating PI3K/AKT/GSK3-β signaling pathway. In the antioxidative assay test, 250 μg/mL OpvE scavenged obvious 97.28% DPPH-released free radicals. Pretreatment of OpvE inhibited H2O2-induced oxidative stress and protected against LPS-induced inflammatory injury by respectively regulating the Nrf2/HO-1/COX2 and TLR4/MYD88 signaling pathways. OpvE also showed anti-S. aureus properties with a MIC of 1.2 mg/mL, and with this concentration, OpvE produced an 8.3 ± 0.16 mm inhibition zone on a bacterial plate. Conclusions: This work highlighted the phytochemical character and some bioactivities, as well as the underline mechanism, which would support the further studies and application of O. vulgatum Linn. Full article
(This article belongs to the Special Issue Antioxidant and Anti-Inflammatory Effects of Natural Product Extracts)
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16 pages, 3047 KB  
Article
Two-Dimensional Chromatographic Isolation of High Purity Erinacine A from Hericium erinaceus
by Katerina Naumoska, Andrej Gregori and Alen Albreht
J. Fungi 2025, 11(2), 150; https://doi.org/10.3390/jof11020150 - 15 Feb 2025
Cited by 4 | Viewed by 3644
Abstract
A simple and robust two-dimensional chromatographic fractionation protocol for the isolation of the neuroprotective compound erinacine A from Hericium erinaceus is proposed. This production platform yielded 19.4 mg of erinacine A from approximately 130 g of mushroom material, with a chromatographic purity of [...] Read more.
A simple and robust two-dimensional chromatographic fractionation protocol for the isolation of the neuroprotective compound erinacine A from Hericium erinaceus is proposed. This production platform yielded 19.4 mg of erinacine A from approximately 130 g of mushroom material, with a chromatographic purity of 97.4%. The procedure includes extraction, concentration, fractionation, purification, and characterisation of the bioactive compound. The crude H. erinaceus extract was fractionated in the first dimension by normal-phase flash chromatography, and the fraction containing erinacine A was further purified in the second dimension by semi-preparative reversed-phase chromatography. This strategy utilises the orthogonality of the two chromatographic modes to effectively eliminate difficult impurities, including structural isomers and analogues of erinacine A. Complementary analytical approaches such as high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography with ultraviolet and tandem mass spectrometric detection (HPLC–UV–MS/MS) were employed to unambiguously confirm erinacine A in the isolated fractions, while HPLC with a charged aerosol detector (CAD) was used to determine its purity. Given the limited commercial availability and the high price of erinacine A, the described method offers a straightforward and cost-effective alternative to obtain this valuable compound for further research and applications. Full article
(This article belongs to the Section Fungi in Agriculture and Biotechnology)
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24 pages, 5128 KB  
Article
Polyacrylate Latex Coating Binders Comprising Polypyrrole Component Prepared with “One-Pot” Synthesis
by Karolína Boštíková, Miroslav Kohl, Andréa Kalendová, Petr Knotek, Miroslava Trchová, Jaroslav Stejskal, Eva Schmidová and Jana Machotová
Coatings 2024, 14(12), 1565; https://doi.org/10.3390/coatings14121565 - 13 Dec 2024
Viewed by 2153
Abstract
This work deals with the coating properties of synthetic latices comprising two kinds of polymers, specifically polyacrylate and polypyrrole, which were simultaneously formed by semi-continuous emulsion polymerization using a “one-pot” synthesis strategy. In this procedure, both the emulsion polymerization of acrylate monomers and [...] Read more.
This work deals with the coating properties of synthetic latices comprising two kinds of polymers, specifically polyacrylate and polypyrrole, which were simultaneously formed by semi-continuous emulsion polymerization using a “one-pot” synthesis strategy. In this procedure, both the emulsion polymerization of acrylate monomers and the oxidative polymerization of pyrrole occurred concurrently in one reactor. Polyacrylate latices differing in polypyrrole loading were prepared by applying various dosages of pyrrole, specifically 0, 0.25, and 0.50, based on the fraction of acrylate monomers. The effect of the in situ incorporated polypyrrole component (having the nature of submicron composite polypyrrole-coated polyacrylate latex particles) on the physico-mechanical properties and chemical resistance of the resulting heterogeneous coating films was investigated. The interaction of incorporated polypyrrole and anti-corrosion pigments (see ZnS, Zn3(PO4)2, ZnFe2O4, MoS2, and ZnO) on the corrosion resistance of coatings was evaluated by using the electrochemical linear polarization technique. The polyacrylate latex prepared with the lowest polypyrrole loading (achieved by polymerizing 0.25 wt. % of pyrrole related to acrylic monomers) was found to be the optimum binder for waterborne anticorrosive coatings based on their properties and protective function. Their compatibility with the selected types of pigments was studied for these latex binders. In addition, their influence on the anti-corrosion efficiency of polyacrylate paint films was evaluated using the linear polarization electrochemical technique. For high corrosion resistance, the ZnS and MoS2 pigments, showing compatibility with polyacrylate latices containing the polypyrrole component, proved to be advantageous. Full article
(This article belongs to the Special Issue Advances in Textile-Based Materials and Polymer Composite Coatings)
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16 pages, 3820 KB  
Article
Simple Green Purification of Spilanthol from Natural Deep Eutectic Solvent and Ethanolic Acmella oleracea (L.) R.K. Jansen Extracts Using Solid-Phase Extraction
by Fabian Alperth, Sebastian Erhart, Olaf Kunert and Franz Bucar
Separations 2024, 11(8), 251; https://doi.org/10.3390/separations11080251 - 20 Aug 2024
Cited by 2 | Viewed by 3465
Abstract
Spilanthol is a major N-alkylamide constituent of Acmella oleracea (L.) R.K. Jansen with diverse pharmacological properties. We recently showed the applicability of NADES (natural deep eutectic solvents) for the green extraction of spilanthol. However, the purification of targets from NADES poses a [...] Read more.
Spilanthol is a major N-alkylamide constituent of Acmella oleracea (L.) R.K. Jansen with diverse pharmacological properties. We recently showed the applicability of NADES (natural deep eutectic solvents) for the green extraction of spilanthol. However, the purification of targets from NADES poses a challenging step due to their non-volatility. A simple green method to retrieve spilanthol with minimal instrumental effort was devised, fractioning NADES (choline chloride/methylurea, choline chloride/1,2-propanediol, choline chloride/citric acid) and dry ethanolic extracts by SPE on C18 material, eluting merely with ethanolic solutions. The relative distribution of spilanthol and organic adulteration in SPE fractions were detected by HPLC-DAD, followed by scale-up, quantification and purity determination in an NMR-based approach. Isocratic elution with 52% ethanol (v/v) proved suitable in all experiments. The three purest 10 mL fractions combined yielded 12.21 mg spilanthol at 71.65% purity from NADES extract ChCl/P (choline chloride/1,2-propanediol, molar ratio 1:2, +20% m/m water). Ethanolic extract samples showed purities ranging from 77.27 to 80.27% in combined raw fractions. For all samples, purity increased by removing non-soluble substances from organic solutions. Pooled NADES extract fractions showed 89.71% in final samples, ethanolic extracts 87.25 to 91.93%. The highest purities of individual fractions per extract were 89.23 to 94.15%. This cheap and simple purification process is promising to acquire spilanthol for research purposes or as a sample preparation step before HPLC on a semi-preparative to preparative scale, as the substance is highly priced and scarcely available on the market. Organic solvents can be reused, and preliminary scale-up possibilities are shown. Full article
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16 pages, 4866 KB  
Article
Model Prediction and Experimental Validation of Transverse Permeability of Large-Tow Carbon Fiber Composites
by Yu Feng, Qiaoxin Zhang, Jun Rao and Dong Liu
Polymers 2024, 16(9), 1266; https://doi.org/10.3390/polym16091266 - 1 May 2024
Cited by 7 | Viewed by 2267
Abstract
Large-tow carbon fiber (LCF) meets the low-cost requirements of modern industry. However, due to the large and dense number of monofilaments, there are problems with uneven and insufficient infiltration during material preparation. The permeability of large-tow carbon fibers can be used as a [...] Read more.
Large-tow carbon fiber (LCF) meets the low-cost requirements of modern industry. However, due to the large and dense number of monofilaments, there are problems with uneven and insufficient infiltration during material preparation. The permeability of large-tow carbon fibers can be used as a two-scale expression of resin flow during infiltration, making it an important factor to consider. This paper provides support for the study of pore formation. A two-dimensional model of randomly bundled large-filament carbon fibers is generated based on scanning electron microscope (SEM) maps. Microstructure size parameters are obtained, and a semi-analytical model of the transverse permeability of large-filament-bundled carbon fibers is established. Permeability values are then obtained. The analysis shows that the monofilaments in the tow are arranged randomly, and their periodic arrangement cannot be used to calculate permeability. Additionally, the number of monofilaments in a carbon fiber tow of the same volume fraction affects the permeability of the tow. Therefore, the permeability model of large-tow carbon fibers is reliable. Full article
(This article belongs to the Section Polymer Physics and Theory)
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15 pages, 313 KB  
Article
Chemical Properties, Ruminal Fermentation, Gas Production and Digestibility of Silages Composed of Spineless Cactus and Tropical Forage Plants for Sheep Feeding
by Paulo Fernando Andrade Godoi, André Luiz Rodrigues Magalhães, Gherman Garcia Leal de Araújo, Airon Aparecido Silva de Melo, Tiago Santos Silva, Glayciane Costa Gois, Kelly Cristina dos Santos, Daniel Bezerra do Nascimento, Priscila Barreto da Silva, Juliana Silva de Oliveira, Edson Mauro Santos, Thieres George Freire da Silva, Anderson de Moura Zanine, Daniele de Jesus Ferreira, Tadeu Vinhas Voltolini and Fleming Sena Campos
Animals 2024, 14(4), 552; https://doi.org/10.3390/ani14040552 - 7 Feb 2024
Cited by 11 | Viewed by 2282
Abstract
The aim was to evaluate the chemical composition, carbohydrates, protein fractionation and in vitro gas production of silages composed of spineless cactus and tropical forages and their effect on sheep performance. Treatments consisted of silages: corn silage (CS), spineless cactus silage (SCS), spineless [...] Read more.
The aim was to evaluate the chemical composition, carbohydrates, protein fractionation and in vitro gas production of silages composed of spineless cactus and tropical forages and their effect on sheep performance. Treatments consisted of silages: corn silage (CS), spineless cactus silage (SCS), spineless cactus + gliricidia (SCG), spineless cactus + buffel grass silage (SCBG) and spineless cactus + pornunça (SCP). Silos were opened 60 days after ensiling, and analyses were carried out. The digestibility test lasted for 36 days, with eight animals per treatment. A completely randomized design was adopted. Considering carbohydrate fractionation, CS, SCS and SCBG silages had higher total carbohydrate content (p = 0.001). The SCS silage presented a higher A + B1 fraction (p = 0.001). The SCBG and SCG silages showed a higher B2 fraction (p < 0.0001) compared to the CS and SCS silages. The SCBG and SCP silages presented a higher C fraction (p = 0.001). For protein fractionation, the SCP and SCG silages showed higher crude protein contents (p = 0.001). The CS and SCS silages showed a higher A fraction (p = 0.001). The SCBG silage presented a higher B1 + B2 fraction (p = 0.001). The SCG silage showed a higher B3 fraction (p = 0.006) compared to SCBG silage. The SCS and SCP silages showed a higher C fraction (p = 0.001). Exclusive SCS silage showed higher in vitro dry matter digestibility (p = 0.001), dry matter degradability (p = 0.001) and total gas production (p = 0.001). The use of the SCBG, SCP and SCG silages to feed sheep increased the dry matter intake (p < 0.001). Sheep fed the SCG silage showed greater dry matter and crude protein digestibility compared to the sheep fed the CS, SCS and SCP silages (p = 0.002). There was a higher water intake (p < 0.001) with the use of the SCS and SCG silages to feed the sheep. The SCP and SCG silages provided a greater intake (p < 0.001) and excretion (p < 0.001) of nitrogen by the animals. Although there were no differences between the treatments for daily gains, lambs that received the spineless cactus-based silage associated with tropical forages showed higher gains (160–190 g/day) than lambs that received CS silage (130 g/day). Thus, the use of spineless cactus associated with buffelgrass, pornunça and gliricidia to prepare mixed silages (60:40) to feed sheep has potential use to feed sheep, with positive effects on nutrient degradation and increases in dry matter intake. Under experimental conditions, we recommend the exclusive use of spineless cactus silage associated with buffel grass, pornunça and gliricidia in feeding sheep in semi-arid regions, as it provides nutrients, water and greater daily gains compared to corn silage. Full article
(This article belongs to the Section Animal Nutrition)
18 pages, 8521 KB  
Article
New Polyene Macrolide Compounds from Mangrove-Derived Strain Streptomyces hiroshimensis GXIMD 06359: Isolation, Antifungal Activity, and Mechanism against Talaromyces marneffei
by Zhou Wang, Jianglin Yin, Meng Bai, Jie Yang, Cuiping Jiang, Xiangxi Yi, Yonghong Liu and Chenghai Gao
Mar. Drugs 2024, 22(1), 38; https://doi.org/10.3390/md22010038 - 8 Jan 2024
Cited by 11 | Viewed by 3796
Abstract
Mangrove-derived actinomycetes represent a rich source of novel bioactive natural products in drug discovery. In this study, four new polyene macrolide antibiotics antifungalmycin B-E (14), along with seven known analogs (511), were isolated from the [...] Read more.
Mangrove-derived actinomycetes represent a rich source of novel bioactive natural products in drug discovery. In this study, four new polyene macrolide antibiotics antifungalmycin B-E (14), along with seven known analogs (511), were isolated from the fermentation broth of the mangrove strain Streptomyces hiroshimensis GXIMD 06359. All compounds from this strain were purified using semi-preparative HPLC and Sephadex LH-20 gel filtration while following an antifungal activity-guided fractionation. Their structures were elucidated through spectroscopic techniques including UV, HR-ESI-MS, and NMR. These compounds exhibited broad-spectrum antifungal activity against Talaromyces marneffei with minimum inhibitory concentration (MIC) values being in the range of 2–128 μg/mL except compound 2. This is the first report of polyene derivatives produced by S. hiroshimensis as bioactive compounds against T. marneffei. In vitro studies showed that compound 1 exerted a significantly stronger antifungal activity against T. marneffei than other new compounds, and the antifungal mechanism of compound 1 may be related to the disrupted cell membrane, which causes mitochondrial dysfunction, resulting in leakage of intracellular biological components, and subsequently, cell death. Taken together, this study provides a basis for compound 1 preventing and controlling talaromycosis. Full article
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16 pages, 5051 KB  
Article
Investigating the Mitoprotective Effects of S1P Receptor Modulators Ex Vivo Using a Novel Semi-Automated Live Imaging Set-Up
by Rebecca Ludwig, Bimala Malla, Maria Höhrhan, Carmen Infante-Duarte and Lina Anderhalten
Int. J. Mol. Sci. 2024, 25(1), 261; https://doi.org/10.3390/ijms25010261 - 23 Dec 2023
Cited by 2 | Viewed by 2205
Abstract
In multiple sclerosis (MS), mitochondrial alterations appear to contribute to disease progression. The sphingosine-1-phosphate receptor modulator siponimod is approved for treating secondary progressive MS. Its preceding compound fingolimod was shown to prevent oxidative stress-induced alterations in mitochondrial morphology. Here, we assessed the effects [...] Read more.
In multiple sclerosis (MS), mitochondrial alterations appear to contribute to disease progression. The sphingosine-1-phosphate receptor modulator siponimod is approved for treating secondary progressive MS. Its preceding compound fingolimod was shown to prevent oxidative stress-induced alterations in mitochondrial morphology. Here, we assessed the effects of siponimod, compared to fingolimod, on neuronal mitochondria in oxidatively stressed hippocampal slices. We have also advanced the model of chronic organotypic hippocampal slices for live imaging, enabling semi-automated monitoring of mitochondrial alterations. The slices were prepared from B6.Cg-Tg(Thy1-CFP/COX8A)S2Lich/J mice that display fluorescent neuronal mitochondria. They were treated with hydrogen peroxide (oxidative stress paradigm) ± 1 nM siponimod or fingolimod for 24 h. Afterwards, mitochondrial dynamics were investigated. Under oxidative stress, the fraction of motile mitochondria decreased and mitochondria were shorter, smaller, and covered smaller distances. Siponimod partly prevented oxidatively induced alterations in mitochondrial morphology; for fingolimod, a similar trend was observed. Siponimod reduced the decrease in mitochondrial track displacement, while both compounds significantly increased track speed and preserved motility. The novel established imaging and analysis tools are suitable for assessing the dynamics of neuronal mitochondria ex vivo. Using these approaches, we showed that siponimod at 1 nM partially prevented oxidatively induced mitochondrial alterations in chronic brain slices. Full article
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17 pages, 5313 KB  
Review
Pros and Cons of Separation, Fractionation and Cleanup for Enhancement of the Quantitative Analysis of Bitumen-Derived Organics in Process-Affected Waters—A Review
by Ralph Hindle, John Headley and Douglas G. Muench
Separations 2023, 10(12), 583; https://doi.org/10.3390/separations10120583 - 24 Nov 2023
Cited by 3 | Viewed by 2495
Abstract
Oil sands process-affected water (OSPW) contains a diverse mixture of inorganic and organic compounds. Naphthenic acids (NAs) are a subset of the organic naphthenic acid fraction compounds (NAFCs) and are a major contributor of toxicity to aquatic species. Thousands of unique chemical formulae [...] Read more.
Oil sands process-affected water (OSPW) contains a diverse mixture of inorganic and organic compounds. Naphthenic acids (NAs) are a subset of the organic naphthenic acid fraction compounds (NAFCs) and are a major contributor of toxicity to aquatic species. Thousands of unique chemical formulae are measured in OSPW by accurate mass spectrometry and high-resolution mass spectrometry (MS) analysis of NAFCs. As no commercial reference standard is available to cover the range of compounds present in NAFCs, quantitation may best be referred to as “semi-quantitative” and is based on the responses of one or more model compounds. Negative mode electrospray ionization (ESI-) is often used for NAFC measurement but is prone to ion suppression in complex matrices. This review discusses aspects of off-line sample preparation techniques and liquid chromatography (LC) separations to help reduce ion suppression effects and improve the comparability of both inter-laboratory and intra-laboratory results. Alternative approaches to the analytical parameters discussed include extraction solvents, salt content of samples, extraction pH, off-line sample cleanup, on-line LC chromatography, calibration standards, MS ionization modes, NAFC compound classes, MS mass resolution, and the use of internal standards. Full article
(This article belongs to the Topic Advances in Spectroscopic and Chromatographic Techniques)
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