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17 pages, 1705 KB  
Article
Oxidative Potential of Water-Soluble Fractions in Road Dust from Huainan, a Typical Coal Resource-Based City in East China: Characteristics and Influencing Factors
by Nini Pang, Jingfeng Wu, Wandong Chu, Xianlin Mo, Zhao Lv, Guichun Zhou, Jie Wu and Jinggang Wang
Water 2026, 18(13), 1587; https://doi.org/10.3390/w18131587 (registering DOI) - 29 Jun 2026
Abstract
The oxidative potential (OP) of atmospheric particulate matter serves as an effective indicator for assessing the health risks posed by reactive oxygen species (ROS). Existing studies have mainly focused on conventional particulate matter including PM2.5, whereas systematic investigations into the OP [...] Read more.
The oxidative potential (OP) of atmospheric particulate matter serves as an effective indicator for assessing the health risks posed by reactive oxygen species (ROS). Existing studies have mainly focused on conventional particulate matter including PM2.5, whereas systematic investigations into the OP of road dust in coal–resource–based cities are still limited. Taking Huainan City, China as the study area, this paper explored the characteristics and influencing factors of OP in water–soluble fractions of road dust from different functional zones. The results indicated that the OP of water-soluble fractions in road dust from Huainan City was 0.162 ± 0.079 pmol/min/μg, with the value in the coal mining zone being significantly lower than that in the commercial and industrial zones. The average concentration of water–soluble organic carbon (WSOC) was 67.3 ± 59.4 mg/kg, with lower levels observed in the coal mining and power plant zones. WSOC was primarily dominated by fulvic acid–like (C1) and tryptophan–like (C2) components. C1 prevailed in coal mining, power plant, and other functional zones, whereas C2 was dominant in commercial, park and residential zones. Overall, the WSOC showed a mixed-source signature dominated by endogenous sources and characterized by a low degree of humification. The total concentration of water–soluble heavy metals in road dust was 43.46 mg/kg, dominated by Fe, Sr, Cu, Ba, and Mn, with relatively lower concentrations observed in the industrial and coal mining zones. The influencing factors of OP exhibited differentiation among functional zones: in industrial zones, it was regulated by As, Mn, TC (total carbon), WSOC and its fluorescent components, while in non-industrial zones, it was closely associated with Co, TC, and WSOC. These findings indicate that road dust toxicity and its key chemical drivers in coal mining and power plant zones of coal resource–based cities exhibit distinctive characteristics. This study provides a scientific basis for the precise management of road dust pollution and the prevention of associated health risks. Full article
(This article belongs to the Section Water and One Health)
25 pages, 1191 KB  
Review
Wood Fibres as Partial Peat Substitutes in Forest Nursery Substrates: Practical Performance, Management Implications, and Remaining Research Questions
by Andis Lazdiņš, Arta Bārdule, Viktorija Vendiņa, Dagnija Lazdiņa, Edijs Ločmels and Inese Kluce
Forests 2026, 17(7), 761; https://doi.org/10.3390/f17070761 (registering DOI) - 29 Jun 2026
Abstract
This review evaluates the current state of knowledge on the use of wood fibres and related woody materials as partial substitutes for peat in substrates used for forest nursery production, with particular emphasis on container seedlings. The review was prepared as a structured [...] Read more.
This review evaluates the current state of knowledge on the use of wood fibres and related woody materials as partial substitutes for peat in substrates used for forest nursery production, with particular emphasis on container seedlings. The review was prepared as a structured narrative synthesis of the available literature, focusing on substrate composition, physical and chemical properties, tree seedling growth, root development, water regime, fertilisation, operational handling, economic aspects and remaining research needs. The available evidence shows that wood fibres are technically promising components of peat-reduced growing media, but their performance depends strongly on the raw-material origin, processing method, substrate proportion, tree species, and cultivation management. The most reliable results have been obtained with partial substitution systems, whereas peat-free solutions remain species-specific and require careful optimisation of irrigation, nitrogen supply, pH control, and substrate quality. Although wood-based materials may improve resource efficiency and, under favourable local conditions, reduce substrate costs, wider implementation is constrained by variable material quality, limited standardisation and insufficient operational-scale validation. The main remaining research need is to define species-specific application thresholds and management protocols and to link nursery performance with outplanting success and full production economics under commercial conditions. Full article
(This article belongs to the Section Forest Ecology and Management)
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15 pages, 1534 KB  
Article
Bovine Serum Albumin Enhances the Quantitative Performance of Polydimethylsiloxane-Based Chamber Digital PCR by Suppressing Surface Adsorption
by Eri Tsunoi, Kazuo Hosokawa, Hitoshi Ohmori and Kae Sato
Micromachines 2026, 17(7), 791; https://doi.org/10.3390/mi17070791 (registering DOI) - 28 Jun 2026
Abstract
Polydimethylsiloxane (PDMS) surfaces are highly hydrophobic, and non-specific biomolecule adsorption is a well-known limitation in microfluidic PCR systems. Flow-based microfluidic PCR has been extensively studied, but the impact of surface adsorption on quantitative performance in closed-chamber digital PCR (dPCR) platforms remains poorly characterized. [...] Read more.
Polydimethylsiloxane (PDMS) surfaces are highly hydrophobic, and non-specific biomolecule adsorption is a well-known limitation in microfluidic PCR systems. Flow-based microfluidic PCR has been extensively studied, but the impact of surface adsorption on quantitative performance in closed-chamber digital PCR (dPCR) platforms remains poorly characterized. This adsorption may reduce the effective concentrations of key reaction components and compromise quantification accuracy. Therefore, in this study, we evaluated two approaches to prevent molecular adsorption in PDMS-based cdPCR systems: (i) the addition of chemical additives to the PCR reaction mixture and (ii) the incorporation of hydrophilizing agents into PDMS, with solution-phase additives proving more effective in this system. We investigated the effects of the reaction additives bovine serum albumin (BSA), Blocking One-P, and dextran on DNA quantification using a PDMS-based dPCR chip. A single-concentration comparison showed that 1.1% BSA produced the highest average DNA copy number (0.091 ± 0.010 copies/well), compared to the no-additive condition (0.039 ± 0.010 copies/well), corresponding to an approximately 2.3-fold increase, whereas Blocking One-P and dextran had no substantial effects. Dilution series experiments were then conducted under BSA-added and BSA-free conditions using plasmid DNA and cDNA derived from HSC4 cells as templates. In both cases, BSA improved quantitative linearity, as reflected by the increased slopes and coefficients of determination. Full article
(This article belongs to the Special Issue Microfluidic Chips for Biomedical Applications)
28 pages, 4235 KB  
Article
Multivariable Model for Understanding the Sandpaper Manufacturing Process
by Mariana Narváez-Merino, Uziel Mejía-González, Mario Aguilar-Fernández, Misaela Francisco-Márquez and Javier Cruz-Salgado
Appl. Syst. Innov. 2026, 9(7), 138; https://doi.org/10.3390/asi9070138 (registering DOI) - 27 Jun 2026
Viewed by 90
Abstract
In this study, we analyze the production process capability of sandpaper manufacturing, with an emphasis on material removal from the finished product and the identification of manufacturing variables that most influence grinding performance and final quality. To this end, the CRISP-DM methodology was [...] Read more.
In this study, we analyze the production process capability of sandpaper manufacturing, with an emphasis on material removal from the finished product and the identification of manufacturing variables that most influence grinding performance and final quality. To this end, the CRISP-DM methodology was applied along with linear regression, stepwise analysis, and principal component analysis (PCA) to a sample of 62 operational variables collected between 2024 and 2025. These variables were reduced to 12 critical dimensions that explain 80% of the process variability. This study highlights the interaction between chemical properties of the adhesive system (gel time, pH, and formaldehyde concentration) and fine mechanical adjustments (blade and roller clearance), showing how these variables jointly affect sanding performance. By integrating these factors into a multivariate framework, PCA allows for the identification of latent relationships, reduces process complexity, and establishes a statistical basis for standardization and continuous improvement, with the aim of supporting the transfer of technical knowledge in industrial manufacturing environments. The proposed framework is intended to support technical knowledge transfer in industrial manufacturing environments. Full article
(This article belongs to the Section Applied Mathematics)
18 pages, 4092 KB  
Article
Oxygen Spillover and Local W6+/W4+ Redox at MnOx@Na2WO4/SiO2 Interfaces: Thermodynamic–Kinetic Origin of Selective CH4 to C2 Oxidation Under Near-Ambient Pressure
by S. N. Osmanova, E. H. Ismailov, A. I. Rustamova, Y. A. Abdulazimova, G. F. Mammadova, L. V. Huseynova, L. Kh. Qasimova, Sh. F. Tagiyeva, M. Vorochta and J. W. Thybaut
Catalysts 2026, 16(7), 586; https://doi.org/10.3390/catal16070586 (registering DOI) - 26 Jun 2026
Viewed by 177
Abstract
A working-state model is proposed for the MnOx–Na2WO4/SiO2 catalyst in oxidative coupling of methane (OCM), where a Na2WO4-rich surface environment forms an adaptive interphase that buffers the effective interfacial oxygen chemical potential and stabilizes [...] Read more.
A working-state model is proposed for the MnOx–Na2WO4/SiO2 catalyst in oxidative coupling of methane (OCM), where a Na2WO4-rich surface environment forms an adaptive interphase that buffers the effective interfacial oxygen chemical potential and stabilizes cooperative MnOx/Na–WOx/Mn–O–W motifs. A thermodynamic-kinetic scheme is developed that relates (1) reaction-induced surface enrichment (structural stabilization), (2) oxygen spillover (damping of local oxygen gradients), and (3) Mn ↔ W redox exchange as an electron-oxygen buffer channel. Ex situ XPS/EDS/EPR data indicate a dynamically stratified near-surface region with chemically heterogeneous environments of Mn, W, and O. The W 4f region remains dominated by the W6+ contribution in the presence of a minor reduced component after OCM. In oxygen-deficient mixtures (CH4/O2 > 4), interfacial reconstruction becomes more pronounced: Mn-centered Mars–van Krevelen chemistry determines CH4 activation and oxygen exchange, while the Na2WO4-rich phase ensures fast ion/oxygen transport. Observation of the EPR signal from W5+ ions in the tungstate matrix indicates the existence of reduced W intermediates at low oxygen potential. Optimization of C2 selectivity and stability is suggested to require maintaining the catalyst within the selective window of effective interfacial μO by adjusting CH2/O2 and contact time, as well as controlling the architecture of the Na–W–O/MnOx interfacial region. Full article
(This article belongs to the Section Environmental Catalysis)
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19 pages, 2299 KB  
Article
Unveiling the Role of Formulation and Process Variables in Nanoemulsion Preparation: A Data-Driven Approach Using High-Energy Ultrasonication
by Diego Romano Perinelli, Ledjan Malaj, Laetitia Novelli, Marco Cespi and Giulia Bonacucina
Pharmaceutics 2026, 18(7), 786; https://doi.org/10.3390/pharmaceutics18070786 (registering DOI) - 26 Jun 2026
Viewed by 170
Abstract
Background: Oil-in-water nanoemulsions (NEs) represent versatile platforms for the delivery of hydrophobic compounds and find a wide range of applications in different fields such as food, cosmetics, agriculture, pharmaceutics, and oil and gas industries. Various methodologies can be applied for the preparation of [...] Read more.
Background: Oil-in-water nanoemulsions (NEs) represent versatile platforms for the delivery of hydrophobic compounds and find a wide range of applications in different fields such as food, cosmetics, agriculture, pharmaceutics, and oil and gas industries. Various methodologies can be applied for the preparation of NEs as low-energy and high-energy methods. Among them, high-energy ultrasonication (HEU) is a popular technique in research laboratories or small manufacturing facilities. However, a clear gap remains in understanding how, and to what extent, experimental parameters and the chemical and physical characteristics of the components affect the formation and properties of NEs through HEU. Methods: In this work, a comprehensive screening of factors (oil viscosity and density, surfactant type, processing parameters, and formulation composition) affecting NEs formation and quality was performed and an artificial neural network (ANN) was applied to determine the relative relevance of each parameter. Results: Oil viscosity revealed to be the primary factor affecting droplet size (Zavg) and polydispersity index (PDI), with high-viscosity oils leading to poor emulsification into nanosized droplets. Higher processing temperatures improved NE formation by reducing viscosity during sonication. Ultrasound amplitude and pulse mode influenced NE characteristics, particularly under challenging conditions. Surfactant type and oil content had, instead, minor effects on the NEs’ features. ANN modelling accurately predicted NEs’ properties and identified critical viscosity limits for successful nanosized emulsification (Zavg < 300 nm and PDI < 0.4). Conclusions: These findings provide a predictive basis for rational NE design under HEU, serving as a guide for researchers working in different fields. Full article
(This article belongs to the Section Physical Pharmacy and Formulation)
17 pages, 2151 KB  
Article
Investigation of Odor, Volatile Organic Compounds (VOC), and Total Organic Carbon (TOC) Parameters Originating from Textile Industry Stenter Stack
by Ezgi Karabacak, Güray Çelik, Fatma Esen, Nezih Kamil Salihoğlu, Taner Yonar, Feza Örüç, Simge Çağlar and Berna Kırıl Mert
Toxics 2026, 14(7), 560; https://doi.org/10.3390/toxics14070560 (registering DOI) - 26 Jun 2026
Viewed by 185
Abstract
The textile industry causes significant environmental problems because of its intensive use of water, energy, and chemicals. The stenter machines, which are commonly used in textile finishing processes, release air pollutants such as odor, volatile organic compounds (VOCs), and total organic carbon (TOC) [...] Read more.
The textile industry causes significant environmental problems because of its intensive use of water, energy, and chemicals. The stenter machines, which are commonly used in textile finishing processes, release air pollutants such as odor, volatile organic compounds (VOCs), and total organic carbon (TOC) into the atmosphere during drying and fixing processes carried out at high temperatures. The aim of this study was to investigate odor, VOC, and TOC emissions from the stacks of the stenter machines. In this study, odor, VOC, and TOC parameters were examined in samples from the stacks of stenter machines of nine different plants operating in the textile sector in Bursa, Turkey. The samples were analysed in accordance with EN 13725:2022 standard, EN 13649:2014 standard, and EN 12619:2013 standard for odor, VOC, and TOC parameters, respectively. Acetone, carbon tetrachloride, dibromochloromethane, ethylbenzene, tetrachlorethylene, toluene, and p + m-Xylene were the most common components. The TOC concentrations were determined in the range of 13.89–279.23 mg/Nm3. The odor concentrations were determined in the range of 4113–26,627 OU/m3. Full article
(This article belongs to the Section Air Pollution and Health)
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20 pages, 27050 KB  
Article
Aging Trajectory Analysis of Asphalt: Differential Regulation of UV Aging Processes by Anti-Aging Agents with Varied Mechanisms
by Hui Wang, Ping Li, Le Yang, Xingzhen Zang, Longyuan Su and Jingzhuo Zhao
Materials 2026, 19(13), 2740; https://doi.org/10.3390/ma19132740 (registering DOI) - 26 Jun 2026
Viewed by 148
Abstract
In this study, four types of anti-ultraviolet aging agents—layered double hydroxides (LDHs), organic montmorillonite (OMMT), titanium dioxide (TiO2), and ultraviolet absorber (UV326)—were employed to modify asphalt. The modified asphalt samples underwent Rolling Thin Film Oven Test (RTFOT) and xenon-lamp aging treatments, [...] Read more.
In this study, four types of anti-ultraviolet aging agents—layered double hydroxides (LDHs), organic montmorillonite (OMMT), titanium dioxide (TiO2), and ultraviolet absorber (UV326)—were employed to modify asphalt. The modified asphalt samples underwent Rolling Thin Film Oven Test (RTFOT) and xenon-lamp aging treatments, and we examined the evolution of their physical properties, rheological performance, and chemical composition. A principal component analysis (PCA) model built on representativeness, discriminative power, and non-redundancy reduced the multidimensional data to two principal components, which together captured 87.540% of the total variance. The dynamic principal component trajectories, plotted from the reduced-dimension data for the unaged–short-term-aged–xenon-lamp-aged process, revealed that anti-aging agents sharing the same protection mechanism led to comparable rates of high- and low-temperature performance deterioration during xenon-lamp aging, whereas agents with different mechanisms resulted in distinctly different patterns of performance deterioration. In the critical xenon-lamp aging stage, the neat asphalt exhibited a trajectory vector change of ΔPC1 = 0.92 and ΔPC2 = 1.25, corresponding to an angle of 54°, reflecting a low-temperature degradation. By contrast, the physical shielding agents LDHs and OMMT produced much steeper trajectories with angles of approximately −80°, where ΔPC2 values rose to as high as 3.67 and 2.19 respectively despite modest reductions in overall aging. The reflective agent TiO2 showed a more moderate angle of 84°, with ΔPC1 and ΔPC2 values of 0.16 and 1.45, indicating a slight retardation of high-temperature performance loss. Notably, the UV absorber UV326 maintained the same trajectory angle of 56° as the neat asphalt but with reduced magnitudes of ΔPC1 = 0.63 and ΔPC2 = 0.94, suggesting a balanced delay in aging without altering its relative progression. This study proposes a novel analytical framework for mechanism-based clustering analysis and the precise selection of anti-aging agents for asphalt. Full article
(This article belongs to the Section Construction and Building Materials)
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27 pages, 14059 KB  
Article
Unveiling the Pharmacological Potential of Anisosciadium orientale: An Integrative Analysis of Cytotoxicity, Molecular Docking, and Apoptotic Pathways
by Amr S. Abouzied, Wafaa M. Fouda, Mohamed K. S. El-Nagar, Bader Huwaimel, Saad Alqarni, Ali Alghubayshi, Talal Alotaibi, May S. Alanazi, Farah A. Alanazi, Nouf Rakan Alobaid and Mohamed S. Refaey
Int. J. Mol. Sci. 2026, 27(13), 5767; https://doi.org/10.3390/ijms27135767 - 26 Jun 2026
Viewed by 198
Abstract
Cancer remains the foremost cause of death globally and presents a major obstacle to increasing life expectancy. The identification of natural anticancer agents is therefore a key research priority. Essential oils (EOs), widely used in traditional medicine, possess diverse biological activities that warrant [...] Read more.
Cancer remains the foremost cause of death globally and presents a major obstacle to increasing life expectancy. The identification of natural anticancer agents is therefore a key research priority. Essential oils (EOs), widely used in traditional medicine, possess diverse biological activities that warrant systematic investigation. Anisosciadium orientale is traditionally regarded as a safe, edible herb; however, its therapeutic potential has not been extensively explored. In this study, the chemical profile of the EO obtained from the aerial parts of A. orientale was characterized using GC–MS analysis. Antioxidant activity was evaluated through hydrogen peroxide and ABTS radical-scavenging assays, whereas anticancer effects and underlying mechanisms were evaluated in multiple cancer cell lines using MTT cytotoxicity assays, flow cytometry, and molecular docking studies. Sixty constituents were identified in the EO, with myristicin and its isomer among the major components. The EO exhibited notable antioxidant and anticancer activities, demonstrating cytotoxicity against lung carcinoma A549 cells with an IC50 of 84.8 µg/mL and inducing significant apoptosis accompanied by G2/M cell-cycle arrest. Treatment with the EO markedly boosted levels of caspase-3, p53, Bax, and the Bax/Bcl-2 ratio, while downregulating Bcl-2 expression. Molecular docking revealed strong binding affinities of major constituents—particularly myristicin and its isomer—toward the EGFR kinase active site, suggesting a high degree of complementarity with the EGFR kinase domain. Collectively, this study represents the first comprehensive study integrating chemical profiling, in vitro cytotoxicity, mechanistic assays, and molecular docking for A. orientale. These findings position A. orientale EO as a promising scaffold for the development of natural anticancer interventions, providing a foundation for future preclinical exploration. Full article
(This article belongs to the Special Issue Molecular Docking Method and Application)
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20 pages, 8609 KB  
Article
Co-Deposition Behavior and High-Voltage Performance of NCM622/Ti4O7 Composite Cathodes Fabricated by Multi-Component Electrophoretic Deposition
by Chan-Hyeok Park, Seong-Yoon Kim and Heon-Cheol Shin
Energies 2026, 19(13), 3014; https://doi.org/10.3390/en19133014 - 26 Jun 2026
Viewed by 155
Abstract
Maintaining a conductive network is essential for achieving high energy density and long-term reliability in lithium-ion batteries. However, its stability is often compromised by structural non-uniformity, and under high-voltage operation, by the oxidative degradation of carbon-based conductive additives. To address these issues, we [...] Read more.
Maintaining a conductive network is essential for achieving high energy density and long-term reliability in lithium-ion batteries. However, its stability is often compromised by structural non-uniformity, and under high-voltage operation, by the oxidative degradation of carbon-based conductive additives. To address these issues, we propose a composite cathode design that combines multi-component electrophoretic deposition (EPD) with a chemically stable Ti4O7 conductive oxide. The EPD conditions were systematically investigated, and an applied voltage of 100 V was identified as the standard voltage for controlling electrode loading while avoiding cracking and delamination under severe deposition conditions. The electrochemical performance of the EPD-derived electrodes depended strongly on the Ti4O7 content in the initial EPD suspension. Ti-0 and Ti-1, prepared from suspensions containing 0 and 1 wt% Ti4O7, respectively, maintained stable capacity delivery over a wide loading range, with areal capacities in good agreement with the theoretical values. In contrast, Ti-5, prepared from a suspension containing 5 wt% Ti4O7, exhibited significant capacity degradation and failed under high-loading conditions. High-voltage cycling over 50 cycles and impedance analysis further showed that Ti-1 exhibited better cycling behavior than Ti-0, with less pronounced resistance growth, whereas Ti-5 displayed poor cycling performance. These results suggest that multi-component EPD with an appropriate amount of Ti4O7 can provide a balanced hybrid conductive network for improving the relative high-voltage cycling behavior of cathodes within the tested condition. Full article
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13 pages, 669 KB  
Article
Electrochemical Deconstruction of Ortho-Phthalate Plasticizers and Recovery of Plasticizing Moieties
by Fabian Dauzvardis and Joel Rosenthal
Compounds 2026, 6(3), 35; https://doi.org/10.3390/compounds6030035 - 26 Jun 2026
Viewed by 85
Abstract
Electrochemical methods for the direct reduction of alkyl esters have been understudied but provide a potential advantage for addressing specific waste streams given that such strategies often require only a minimal chemical profile. One such waste stream that could benefit from electrochemical remediation [...] Read more.
Electrochemical methods for the direct reduction of alkyl esters have been understudied but provide a potential advantage for addressing specific waste streams given that such strategies often require only a minimal chemical profile. One such waste stream that could benefit from electrochemical remediation is poly(vinyl chloride) (PVC) plastics. PVC recycling often faces challenges due to the complexity of such waste. Solvent-based recycling methods pose several advantages for addressing post-use PVC; however, such methods are complicated by the high amounts of toxic legacy plasticizers (ortho-phthalates) present in PVC. A potential solution to addressing such phthalates is to address them electrochemically, coupled with recovery of the resulting valuable products. Presented herein is an optimized electrochemical method for ester activation that is leveraged to separate and recover the aromatic and alkyl components of ortho-phthalate plasticizers. The resulting aliphatic alcohols may be reused to prepare other non-toxic plasticizers. This electro-degradation method is demonstrated on six phthalates that have been identified to pose health concerns in addition to plasticizers recovered from commercial samples of PVC. Full article
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19 pages, 3436 KB  
Article
Long-Term Multivariate Dynamics of Water Quality in the Chicago and Des Plaines River Watersheds: Evidence from Principal Component Analysis (2001–2025)
by Sender Kyeremeh and Sanoar Rahman
Water 2026, 18(13), 1563; https://doi.org/10.3390/w18131563 - 26 Jun 2026
Viewed by 321
Abstract
Urban freshwater systems are subject to complex, interacting anthropogenic stressors that collectively alter hydrological, chemical, and ecological dynamics. This study examines the temporal evolution of water quality across the Chicago River Watershed (CRW) and the Des Plaines River Watershed (DPRW) over a 25-year [...] Read more.
Urban freshwater systems are subject to complex, interacting anthropogenic stressors that collectively alter hydrological, chemical, and ecological dynamics. This study examines the temporal evolution of water quality across the Chicago River Watershed (CRW) and the Des Plaines River Watershed (DPRW) over a 25-year monitoring period (2001–2025). Long-term data from 51 stations were analyzed across ten water quality parameters. Principal component analysis (PCA) was applied annually to characterize shifts in multivariate water quality structure and identify dominant gradients governing system behavior. During the early phase (2001–2012), three principal components described the system, reflecting semi-independent stressor gradients. Beginning in 2013, a marked structural simplification emerged where a single dominant component accounted for approximately 78–84% of total annual variance, indicating strong parameter coupling and consolidation of system variability into a unified response gradient. This transition coincided with measurable declines in total phosphorus, total dissolved solids, and nitrogen. Nevertheless, the persistence of a single dominant gradient underscores the continued influence of urban environmental controls and tightly coupled pollutant pathways. These findings affirm the value of long-term, multivariate monitoring for characterizing urban water quality dynamics and informing adaptive watershed management. Full article
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20 pages, 2210 KB  
Article
Comprehensive Phytochemical Characterization and Quality Evaluation of Taxillus chinensis via Integrated Widely Targeted Metabolomics, HPLC Fingerprinting, and Multi-Component Quantification
by Zhouwei Li, Hongfei Wei, Jiahui Wu, Qiyuan Yang, Jiemei Liang, Xiaoxun Wang and Li Li
Metabolites 2026, 16(7), 446; https://doi.org/10.3390/metabo16070446 - 25 Jun 2026
Viewed by 87
Abstract
Background/Objectives: This study aims to establish a systematic phytochemical characterization and quality evaluation method to systematically evaluate the influence of multiple factors on the chemical composition of Taxillus chinensis, thereby providing a scientific basis for its development, utilization, and quality control standards. [...] Read more.
Background/Objectives: This study aims to establish a systematic phytochemical characterization and quality evaluation method to systematically evaluate the influence of multiple factors on the chemical composition of Taxillus chinensis, thereby providing a scientific basis for its development, utilization, and quality control standards. Methods: To ensure a targeted and representative metabolic screening, six representative batches covering the major geographical origins and host plants were selected for initial metabolomic profiling. An integrated analytical approach combining UPLC-MS/MS-based widely targeted metabolomics, HPLC fingerprinting, and multi-component quantitative analysis with multivariate statistical analysis was employed. Results: Significant quality variations were identified across the samples. Metabolomics results indicated that while chemical component types were qualitatively consistent across growth conditions, their contents varied significantly. Unique differential metabolites clustered according to specific geographical origins or host plants. KEGG pathway analysis revealed that geographical origin primarily regulated phenylpropanoid biosynthesis, whereas host differences mainly influenced flavonoid and monoterpenoid biosynthesis. Furthermore, HPLC fingerprinting of 20 batches demonstrated similarities greater than 0.9, with 15 common peaks determined. Based on their high relative abundance, differential significance across samples, and documented pharmacological relevance to the herb’s traditional efficacy, six bioactive components—gallic acid, catechin, epicatechin, hyperoside, isoquercitrin, and quercitrin—were identified and quantified. Notably, samples originating from Wuzhou exhibited the highest total content of these components. Consistent with PCA and HCA results, gallic acid, hyperoside, isoquercitrin, and quercitrin were identified as potential markers driving quality differences. Conclusions: This integrated approach allows for a systematic analytical screening of Taxillus chinensis, clarifying chemical variations caused by environmental and biological factors, and supporting the standardization and comprehensive utilization of this medicinal plant. Full article
(This article belongs to the Topic Metabolomics in Plants)
24 pages, 4587 KB  
Article
Divergent Altitudinal Responses and Contrasting Environmental Drivers of Rhizome Chemistry in Two Co-Occurring Polygonatum Species
by Zhansheng Tang, Yalei Li, Simin Bao, Xubo Zhou, Shiwei Lin, Chenchen Cai and Lina Xie
Forests 2026, 17(7), 739; https://doi.org/10.3390/f17070739 (registering DOI) - 25 Jun 2026
Viewed by 83
Abstract
Forest understorey herbs are an under-studied component of subtropical mountain forest biodiversity, yet they include several genera of high medicinal and economic value. The rhizomes of Polygonatum (Liliaceae) are a prominent example, but the forest-ecological controls on their bioactive composition in wild populations—particularly [...] Read more.
Forest understorey herbs are an under-studied component of subtropical mountain forest biodiversity, yet they include several genera of high medicinal and economic value. The rhizomes of Polygonatum (Liliaceae) are a prominent example, but the forest-ecological controls on their bioactive composition in wild populations—particularly for co-occurring congeners—remain poorly resolved. We sampled 92 wild plants of Polygonatum cyrtonema and P. filipes along four altitudinal transects (330–1730 m) in a subtropical mountain forest reserve in southeastern China, quantifying total polysaccharide, three flavonoid monomers (rutin, quercetin, and methylophiopogonanone B), and two LC–MS class signals (ΣFlavonoid, ΣSaponin), together with 13 topographic, edaphic, and biotic predictors. The two species displayed the following distinct rhizome chemical phenotypes: P. cyrtonema tended toward higher ΣSaponin; P. filipes toward higher ΣFlavonoid. The clearest pattern was a robust species × altitude interaction for total polysaccharide (p = 0.002), with the two species following opposite altitudinal trajectories. In multivariate forward-selected redundancy analysis, canopy closure and species identity emerged as the only retained environmental predictors, identifying forest light environment as the strongest single environmental correlate of rhizome chemical variation. Species-specific bivariate analyses further revealed contrasting driver hierarchies as follows: P. cyrtonema chemistry tracked topography, whereas P. filipes chemistry tracked rhizosphere soil enzymes and chemistry; only soil temperature and urease activity were shared across species. These results argue that altitude is not a uniform predictor of rhizome chemistry in wild Polygonatum, and support species-specific, canopy-aware management of medicinal forest understorey herbs in subtropical mountain forests. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
19 pages, 3559 KB  
Article
Systematic Identification of Chemical Components and Analysis of Major Constituents of Verbena officinalis L. Based on UHPLC–Q–Exactive–Orbitrap MS Combined with Feature-Based Molecular Networking and SIRIUS Strategy
by Wenqing Xiao, Meng Li, Huibin Luo, Qiru Chen, Liangyin Shu, Liangjun Guan and Shunli Xiao
Molecules 2026, 31(13), 2244; https://doi.org/10.3390/molecules31132244 - 25 Jun 2026
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Abstract
Verbena officinalis L., a classic medicinal plant of the Verbenaceae family with wide clinical applications, contains alkaloids and steroids with potent anti-inflammatory and anti-psoriatic activities. However, its whole-plant chemical composition and pharmacological material basis have not been systematically elucidated. Here, UHPLC–Q–Exactive–Orbitrap MS combined [...] Read more.
Verbena officinalis L., a classic medicinal plant of the Verbenaceae family with wide clinical applications, contains alkaloids and steroids with potent anti-inflammatory and anti-psoriatic activities. However, its whole-plant chemical composition and pharmacological material basis have not been systematically elucidated. Here, UHPLC–Q–Exactive–Orbitrap MS combined with FBMN and SIRIUS software was applied for comprehensive component analysis. A total of 126 constituents were annotated following MSI standards: 15 were unambiguously identified as MSI Level 1 using reference standards, 80 were tentatively assigned to MSI Level 2 via literature MS/MS data and GNPS spectral matching, and the remaining 31 were annotated as MSI Level 3 by in silico prediction with SIRIUS. Among them, 74 compounds were detected in this plant for the first time, and 15 were preliminarily regarded as putative novel candidate constituents. This integrated method shows better isomer resolution than traditional GNPS workflows, greatly improving the efficiency and accuracy of chemical profiling of medicinal plants. Full article
(This article belongs to the Special Issue Extractions and Biological Activities of Medicinal Plants)
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