Molecules

19 pages, 1675 KB

Open AccessArticle

The Effect of Gold Nanoparticles in Sodium Alginate on the Biochemical Characteristics of Garden Cress

by Miłosz Rutkowski, Damian Duda, Ewa Godos, Wojciech Makowski, Emilia Bernaś, Karen Khachatryan, Andrzej Kalisz, Agnieszka Sękara and Gohar Khachatryan

Molecules 2026, 31(8), 1373; https://doi.org/10.3390/molecules31081373 - 21 Apr 2026

Viewed by 722

Abstract

Gold nanoparticles (AuNPs) have numerous applications in science and industry. Therefore, their potential phytotoxicity should be investigated. Garden cress (Lepidium sativum L.) is a useful model plant for assessing the effects of chemicals released into the environment. The aim of this study [...] Read more.

Gold nanoparticles (AuNPs) have numerous applications in science and industry. Therefore, their potential phytotoxicity should be investigated. Garden cress (Lepidium sativum L.) is a useful model plant for assessing the effects of chemicals released into the environment. The aim of this study was to prepare alginate gels containing AuNPs for plant exposure experiments, evaluate their physicochemical properties, and determine their effects on selected biochemical parameters of garden cress seedlings. Gold nanoparticles were synthesized in sodium alginate at an initial concentration of 50 mg/L, using xylose and maltose as reducing agents. The gels were diluted with distilled water to obtain AuNP concentrations of 5 and 25 mg/L. Garden cress seeds were placed on filter paper soaked with the tested formulations, while distilled water and sodium alginate solutions without AuNPs served as controls. After 5 days of incubation at 20 °C under light conditions, the plant material was collected and selected bioactive compounds were determined. AuNP-containing gels significantly affected the biochemical status of the seedlings. In particular, AuNPs synthesized with xylose at 25 mg/L significantly increased the contents of photosynthetic pigments and total polyphenolic compounds. All tested AuNP formulations increased the antioxidant activity of seedlings, suggesting the activation of abiotic stress-related defense responses, however, direct markers of oxidative damage were not assessed in the present study. Overall, the results indicate that alginate-based AuNPs can modify selected biochemical parameters in garden cress seedlings, and these effects depend on nanoparticle concentration and reducing sugar used during synthesis, which may be relevant for the future development of plant-targeted nanomaterials for agricultural applications. Full article

(This article belongs to the Special Issue Bioactive Compounds in Plants: Extraction and Application)

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18 pages, 3021 KB

Open AccessArticle

Organic-Inorganic Co-Modified PVDF Membrane for High-Flux Oil/Water Separation and Simultaneous Multi-Pollutant Removal

by Jie Teng, Zekai Lu, Xiangbo Ma, Wencheng Zhu, Yongqiang Yang, Pu Li and Xia Xu

Molecules 2026, 31(8), 1372; https://doi.org/10.3390/molecules31081372 - 21 Apr 2026

Cited by 1 | Viewed by 642

Abstract

The coexistence of emulsified oil, dissolved organics, and heavy metal ions in industrial oily wastewater makes one-step treatment highly challenging. Herein, an organic-inorganic co-modified PVDF composite membrane (MTSP) was fabricated via nonsolvent-induced phase separation, with tea polyphenols, SiO₂, and fibrous MXene [...] Read more.

The coexistence of emulsified oil, dissolved organics, and heavy metal ions in industrial oily wastewater makes one-step treatment highly challenging. Herein, an organic-inorganic co-modified PVDF composite membrane (MTSP) was fabricated via nonsolvent-induced phase separation, with tea polyphenols, SiO₂, and fibrous MXene synergistically incorporated. The resulting membrane exhibited a superhydrophilic/underwater oleophobic surface, with a water contact angle of 1° and an underwater oil contact angle of ~136°, owing to the optimized surface chemistry and hierarchical pore structure. As a result, the MTSP membrane effectively suppressed oil fouling while enabling rapid water transport. At 0.1 bar, the optimized membrane delivered an oil/water separation efficiency of ~99.5% and a high flux of 2420–2670 L·m⁻²·h⁻¹, while maintaining >99% separation efficiency for various emulsified oils, including kerosene, edible oil, n-hexane, and 1,2-dichloroethane. It also showed excellent recyclability and chemical stability, retaining >98–99% efficiency after five cycles and after 24 h exposure to pH 1 and pH 12 conditions. Notably, for complex simulated wastewater containing emulsified kerosene, phenol, and Fe³⁺, Cu²⁺, Zn²⁺, and Cd²⁺, the membrane maintained ~99% oil/water separation efficiency and simultaneously removed ~79% of phenol and 70–86% of heavy metal ions in a single filtration process. The superior performance is attributed to the synergistic effects of the superhydrophilic/underwater-oleophobic membrane surface, hierarchical transport channels enabling rapid water permeation, and multifunctional sites that adsorb/coordinate dissolved pollutants. This work provides a simple, scalable design strategy for PVDF-based membranes that integrate high-flux separation, antifouling performance, and multi-pollutant remediation for the treatment of complex oily wastewater. Full article

(This article belongs to the Special Issue Advanced Materials for Efficient Adsorption and Separation)

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14 pages, 1206 KB

Open AccessArticle

Green Light-Driven Hydroxylation of Boronic Acids Employing g-C₃N₄ as the Photocatalyst

by Alexandros Emmanouil Troulos, Anastasia Maria Antonaki, Maria Zografaki, Vassilios Binas and Petros L. Gkizis

Molecules 2026, 31(8), 1371; https://doi.org/10.3390/molecules31081371 - 21 Apr 2026

Viewed by 699

Abstract

Phenol derivatives display a prominent role in many biologically active molecules. Boron-containing molecules are considered valuable precursors for their synthesis. Therefore, the rise of photochemistry has led many researchers to develop novel, sustainable protocols that exploit the advantages offered by different irradiation sources. [...] Read more.

Phenol derivatives display a prominent role in many biologically active molecules. Boron-containing molecules are considered valuable precursors for their synthesis. Therefore, the rise of photochemistry has led many researchers to develop novel, sustainable protocols that exploit the advantages offered by different irradiation sources. For this reason, the application of novel photocatalysts that promote challenging organic transformations is highly valued. Graphitic carbon nitride (g-C₃N₄) is a semiconductor photocatalyst widely used in organic chemistry for promoting complex organic transformations. Herein, we report a green and efficient methodology for the hydroxylation of boronic acids to the corresponding hydroxyl derivatives, using g-C₃N₄ as the photocatalyst. The heterogeneous photocatalyst (g-C₃N₄) was prepared by thermal polycondensation of melamine and characterized by XRD, FESEM/EDS, and UV–Vis diffuse reflectance spectroscopy. Green LED irradiation was employed as the energy source and air as the active oxidant. A variety of substrates were tested, showcasing excellent functional group tolerance in the aerobic photochemical protocol. Mechanistic studies were conducted to investigate the reaction pathway and to identify the oxygen species generated. Full article

(This article belongs to the Special Issue Innovative Green and Photochemical Approaches for Sustainable Organic Synthesis)

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29 pages, 4591 KB

Open AccessArticle

Palladium(II) Complexes with Chloro-Substituted Salicyl Schiff Bases: Exploring Multimodal Anticancer Mechanisms and Catalase Inhibition

by Jovana S. Dragojević, Žiko Milanović, Kristina Milisavljević, Milena Milutinović, Safija Herenda, Edhem Hasković, Nenad Vanis, Vera M. Divac and Marina D. Kostić

Molecules 2026, 31(8), 1370; https://doi.org/10.3390/molecules31081370 - 21 Apr 2026

Viewed by 537

Abstract

The search for new anticancer agents with improved efficacy and reduced toxicity has intensified interest in metal-based compounds. In this study, two novel palladium(II) complexes, synthesized from Schiff base ligands derived from 5-chloro-salicylaldehyde and p-hydroxybenzylamine or tyramine, were chemically characterized and biologically [...] Read more.

The search for new anticancer agents with improved efficacy and reduced toxicity has intensified interest in metal-based compounds. In this study, two novel palladium(II) complexes, synthesized from Schiff base ligands derived from 5-chloro-salicylaldehyde and p-hydroxybenzylamine or tyramine, were chemically characterized and biologically evaluated. Both complexes exhibited significant cytotoxic activity against the MCF-7 breast cancer cell line in a dose- and time-dependent manner, with Pd2 showing slightly higher potency. Morphological analysis of treated cells indicated that apoptosis is the predominant mechanism of cell death. To gain deeper insight into the potential mechanisms underlying the observed anticancer activity, several biologically relevant targets were investigated. Enzyme kinetics revealed that the complexes act as uncompetitive inhibitors of liver catalase, suggesting a possible role in the induction of oxidative stress. Fluorescence studies demonstrated that Pd2 interacts with CT-DNA through combined intercalative and minor groove binding modes and exhibits significant binding affinity toward human serum albumin, predominantly at Sudlow’s site I. Molecular docking analysis further supported favorable interactions with catalase, estrogen receptor α, and B-form DNA, providing structural insight into the experimentally observed biological effects. Overall, the study explores multiple potential mechanisms of anticancer action, underscoring the promising therapeutic potential of these palladium(II) complexes, while antitumor activity has been initially assessed using a MCF-7 cell line as a preliminary model. Full article

(This article belongs to the Special Issue Transition Metal Complexes in Cancer Therapy: Beyond Platinum)

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37 pages, 1363 KB

Open AccessReview

Biochemistry of Human Gut Microbiota: Related Diseases and Dietary Interactions

by Sude Toydemir and Gokce Merey

Molecules 2026, 31(8), 1369; https://doi.org/10.3390/molecules31081369 - 21 Apr 2026

Viewed by 1308

Abstract

The human gut microbiota represents a complex and dynamic ecosystem of trillions of microorganisms that play a fundamental role in maintaining physiological homeostasis, regulating metabolism, and modulating the immune system. This narrative review explores the biochemical intricacies of the gut microbiome, focusing on [...] Read more.

The human gut microbiota represents a complex and dynamic ecosystem of trillions of microorganisms that play a fundamental role in maintaining physiological homeostasis, regulating metabolism, and modulating the immune system. This narrative review explores the biochemical intricacies of the gut microbiome, focusing on the dominant phyla (Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, Verrucomicrobia, Fusobacteria) and their specific contributions to host health. A critical emphasis is placed on the metabolic outputs of these microorganisms, such as short-chain fatty acids (SCFAs) like butyrate, which serve as vital energy sources and anti-inflammatory signaling molecules. Conversely, the review examines how dysbiosis, the disruption of microbial balance, is mechanistically linked to the pathogenesis of diverse conditions, including obesity, diabetes mellitus, inflammatory bowel disease (IBD), and gout. Furthermore, it highlights the profound impact of dietary interventions on microbial architecture, notably, how non-digestible carbohydrates promote beneficial taxa and eubiosis, while high-fat and high-sugar diets drive metabolic endotoxemia and systemic inflammation. By synthesizing current knowledge on microbial biotransformations of proteins and polyphenols, this work underscores the bidirectional relationship between nutrition and the microbiome. Ultimately, understanding these biochemical interactions is essential for developing targeted probiotic, prebiotic, and nutritional strategies to prevent and manage chronic metabolic and inflammatory disorders. Full article

(This article belongs to the Special Issue Featured Reviews in Chemical Biology 2026)

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18 pages, 7081 KB

Open AccessArticle

Sakuranetin, a Natural Flavonoid, Promising to Manage Grapevine Diseases

by Corentin Griffon, Brice Dautruche, Bilal Loumi, Abdouramane Dosso, David Lesur, Emilie Isidore, Morad Chadni, Florent Allais, Christian Magro, Charles Monteux and Florence Fontaine

Molecules 2026, 31(8), 1368; https://doi.org/10.3390/molecules31081368 - 21 Apr 2026

Viewed by 624

Abstract

Botrytis cinerea and Plasmopara viticola, the causal agents of grey mold and downy mildew, respectively, are two major grapevine pathogens whose control largely relies on synthetic fungicides, raising environmental and health concerns. Plant-derived secondary metabolites, particularly flavonoids involved in plant defense, represent [...] Read more.

Botrytis cinerea and Plasmopara viticola, the causal agents of grey mold and downy mildew, respectively, are two major grapevine pathogens whose control largely relies on synthetic fungicides, raising environmental and health concerns. Plant-derived secondary metabolites, particularly flavonoids involved in plant defense, represent promising sustainable alternatives. Among them, sakuranetin, a flavanone aglycone known for its antifungal activity in rice, remains poorly explored for grapevine protection. In this study, sakuranetin was purified from cherry branches (48 mg) and structurally characterized using UHPLC-ESI-QTOF-MS and NMR analyses. Its antifungal activity against B. cinerea and P. viticola was evaluated through in vitro, in vivo and in planta assays. For B. cinerea, our results showed a significant in vitro inhibition of mycelium growth, with EC₅₀ values of 16.43 mg·L⁻¹, while no protection of detached berries was observed. Against P. viticola, sakuranetin has no effect on the release of zoospores, but there is a total inhibition of spore germination at 1 mg·L⁻¹ in vitro, confirmed in vivo on a foliar disc. In planta, no significant protection is observed at 25 mg·L⁻¹, even if some targeted defense genes are induced. Further studies are needed to determine the best concentration of sakuranetin to use to manage B. cinerea and P. viticola in planta. Full article

(This article belongs to the Special Issue Advances in Extraction, Biological Activity of Natural Products and Their Derivatives)

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16 pages, 633 KB

Open AccessArticle

Antimicrobial Activity of Metal-Based Danofloxacin Complexes Against Pathogenic Microorganisms

by Aleksandra Felczak, Katarzyna Niedziałkowska, Katarzyna Lisowska and Urszula Kalinowska-Lis

Molecules 2026, 31(8), 1367; https://doi.org/10.3390/molecules31081367 - 21 Apr 2026

Cited by 1 | Viewed by 433

Abstract

Fluoroquinolone antibiotics, like danofloxacin, are considered as crucial veterinary drugs due to their high antibacterial potential, a broad spectrum of activity and good pharmacological properties. However, owing to the widespread use of this group of pharmaceuticals, microbial resistance to them is becoming a [...] Read more.

Fluoroquinolone antibiotics, like danofloxacin, are considered as crucial veterinary drugs due to their high antibacterial potential, a broad spectrum of activity and good pharmacological properties. However, owing to the widespread use of this group of pharmaceuticals, microbial resistance to them is becoming a serious worldwide concern. In the present study, novel silver and copper complexes of danofloxacin were prepared and characterized using ¹H NMR, ¹⁹F NMR and IR spectroscopy, ESI-MS spectrometry, and elemental analysis. The antimicrobial properties of the obtained complexes were determined against selected bacterial and fungal strains, including yeast and conidia-forming fungi. Additionally, toxicities of danofloxacin metal-based complex solutions were assessed toward eukaryotic cells. The obtained results indicate that silver(I) and copper(II) complexes of danofloxacin exhibit good antimicrobial activity against bacteria that are important from the veterinary point of view, like Listeria monocytogenes or Campylobacter jejuni, in concentrations which are not cytotoxic. The MBC values of metal-based danofloxacin complexes for the mentioned strains were 1.5 times lower than those obtained for danofloxacin. Additionally, the solution of the novel silver–danofloxacin complex was found to have a fungicidal effect against the studied Candida and Aspergillus strains. Full article

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21 pages, 3276 KB

Open AccessArticle

Assessment of Heavy Metal Forms and Mobility in Bottom Sediments of Anthropogenically Impacted Freshwater Bodies in Belarus

by Elizaveta Dorozhko, Witold Kwapinski and Valentin Romanovski

Molecules 2026, 31(8), 1366; https://doi.org/10.3390/molecules31081366 - 21 Apr 2026

Cited by 1 | Viewed by 506

Abstract

Bottom sediments in anthropogenically impacted freshwater systems represent a dynamic and poorly constrained source of secondary pollution, where heavy metal mobility, rather than total concentration, controls the release of contaminants into the water column under changing physicochemical conditions. This issue is particularly pronounced [...] Read more.

Bottom sediments in anthropogenically impacted freshwater systems represent a dynamic and poorly constrained source of secondary pollution, where heavy metal mobility, rather than total concentration, controls the release of contaminants into the water column under changing physicochemical conditions. This issue is particularly pronounced in small and medium-sized freshwater systems subjected to sustained anthropogenic pressure, where local hydrochemical conditions and sediment composition strongly influence metal speciation and remobilization dynamics. This study aims to quantitatively assess heavy metal speciation, mobility, and associated ecological risk in bottom sediments of anthropogenically impacted freshwater systems using complementary analytical approaches. The data obtained indicate a pronounced spatial heterogeneity in the total metal content, due to varying degrees of anthropogenic impact on the water bodies. The highest level of pollution was recorded in the bottom sediments of the Chizhovskoye reservoir, where Zn concentrations reach 755 mg/kg, Cr—379 mg/kg, Ni—106 mg/kg, and Cu—158 mg/kg, indicating intense technogenic influence. The bottom sediments of the Loshitsa River are characterized by elevated, but less extreme values: the content of Cu is up to 77 mg/kg, Zn—up to 263 mg/kg, and Mn—up to 418 mg/kg. In contrast to urbanized water bodies, the background site—Lake Sergeevskoye—is characterized by significantly lower concentrations of heavy metals, which confirms its representativeness as a control object. Analysis of the fractional composition showed that Zn and Mn have the largest share of mobile forms, with their concentrations in the mobile phase reaching 12–92 mg/kg and 60–116 mg/kg, respectively, especially under conditions of increased anthropogenic load. A significant portion of Cu and Zn (up to 60–70% of the total content) is associated with organic matter, indicating the important role of the organic matrix in retaining metals and their potential mobilization under changing environmental conditions. Calculation of the geoaccumulation index showed that most of the studied bottom sediments belong to the from uncontaminated to moderately contaminated class, while for Cr and Ni in the Chizhovskoye reservoir, I_geo values up to 1.9 are characteristic, corresponding to a moderate level of pollution. The results obtained indicate a significant impact of anthropogenic load on the forms of occurrence and mobility of heavy metals and highlight the role of bottom sediments as an active factor in the secondary pollution of freshwater ecosystems. Full article

(This article belongs to the Special Issue Heavy Metal Pollutants in Water, Wastewater and Sediments: From Occurrence and Determination to Removal and Recovery)

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27 pages, 4624 KB

Open AccessArticle

Structural Characterization and Immunomodulatory Activity of an Acidic Polysaccharide from Rhodomyrtus tomentosa (Aiton) Hassk. Fruits

by Huihui Yin, Guoqing Yan, Yunfu Huang, Xueyan Zeng, Shenhong He, Tianyan Lan and Wei Liu

Molecules 2026, 31(8), 1365; https://doi.org/10.3390/molecules31081365 - 21 Apr 2026

Viewed by 488

Abstract

A polysaccharide from Rhodomyrtus tomentosa (Aiton) Hassk. fruit (RTFP-2b) was isolated and purified. RTFP-2b has a molecular weight of 22.995 kDa and consists of nine monosaccharides, with arabinose (38.68%), galactose (21.86%), and galacturonic acid (14.83%) as its major components. Methylation and NMR analyses [...] Read more.

A polysaccharide from Rhodomyrtus tomentosa (Aiton) Hassk. fruit (RTFP-2b) was isolated and purified. RTFP-2b has a molecular weight of 22.995 kDa and consists of nine monosaccharides, with arabinose (38.68%), galactose (21.86%), and galacturonic acid (14.83%) as its major components. Methylation and NMR analyses revealed dominant glycosidic linkages, including α-L-Araf-(1→, →4)-α-D-GalpA-(1→, →4)-α-D-Galp-(1→, →5)-α-L-Araf-(1→, →3)-α-L-Araf-(1→, →2)-α-L-Rhap-(1→, and →3,4,6)-β-D-Galp-(1→. Bioactivity assays using lipopolysaccharide (LPS)-stimulated RAW264.7 cells showed that RTFP-2b exhibits dose-dependent immunomodulatory properties. When administered at lower concentrations (100–200 μg/mL), RTFP-2b enhanced phagocytosis and IL-1β production. At higher concentrations (300–400 μg/mL), it significantly suppressed nitric oxide and showed biphasic regulation of IL-1β, but unexpectedly increased IL-6 levels in LPS-stimulated RAW264.7 cells. These immunomodulatory effects of RTFP-2b at higher doses were accompanied by inhibition of NF-κB signaling. These findings indicate that RTFP-2b is a structurally distinct acidic polysaccharide with dose-dependent immunomodulatory properties, suggesting its potential application in functional foods or pharmaceuticals. Full article

(This article belongs to the Special Issue Bioactive Compounds from Roots, Stems, Leaves, Flowers, Fruits, and Seeds: 2nd Edition)

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27 pages, 5970 KB

Open AccessArticle

Molecular Insight into the Structural Properties of Deep Eutectic Solvents Based on Alkanolamines—A Theoretical and Experimental Study

by Maciej Śmiechowski, Bartosz Nowosielski, Ingmar Persson, Iwona Cichowska-Kopczyńska and Dorota Warmińska

Molecules 2026, 31(8), 1364; https://doi.org/10.3390/molecules31081364 - 21 Apr 2026

Cited by 1 | Viewed by 508

Abstract

Molecular dynamics simulations were performed on 27 deep eutectic solvents (DESs) composed of various hydrogen bond acceptors (HBAs)—tetrabutylammonium bromide (TBAB), tetrabutylammonium chloride (TBAC), and tetraethylammonium chloride (TEAC)—combined with different hydrogen bond donors (HBDs)—3-aminopropan-1-ol (AP), 2-(methyl-amino)ethanol (MAE), and 2-(n-butylamino)ethanol (BAE). Radial distribution [...] Read more.

Molecular dynamics simulations were performed on 27 deep eutectic solvents (DESs) composed of various hydrogen bond acceptors (HBAs)—tetrabutylammonium bromide (TBAB), tetrabutylammonium chloride (TBAC), and tetraethylammonium chloride (TEAC)—combined with different hydrogen bond donors (HBDs)—3-aminopropan-1-ol (AP), 2-(methyl-amino)ethanol (MAE), and 2-(n-butylamino)ethanol (BAE). Radial distribution functions (RDFs) were computed from the simulation trajectories to probe the microscopic structure of these DESs. The effects of HBA/HBD molar ratio, alkyl chain length, anion type, and the amine group’s substitution on the structural organization of the DESs were systematically investigated. Moreover, the influence of water addition on the structural properties of selected DESs (TBAB with AP, MAE, or BAE at a 1:6 molar ratio) was explored. These structural features were then correlated with previously reported experimental data. To complement the classical simulations, ab initio molecular dynamics simulations were conducted on the same TBAB-based systems, enabling the analysis of electronic structure phenomena, including RDFs, dipole moment distributions, and charge transfer. Furthermore, experimental large-angle X-ray scattering (LAXS) data collection and analysis were performed in terms of the simulated structural data. This multi-scale approach provides a detailed understanding of the structural and electronic characteristics governing the behavior of alkanolamine-based DES. Full article

(This article belongs to the Special Issue New Horizons in Deep Eutectic Solvents (DESs): Synthesis, Characterization and Applications)

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12 pages, 3555 KB

Open AccessArticle

Insights into Carbon Sphere Formation from Glucose and Levoglucosan During Hydrothermal Carbonisation

by Ance Plavniece, Galina Dobele, Kristine Meile, Vilhelmine Jurkjane and Aivars Zhurinsh

Molecules 2026, 31(8), 1363; https://doi.org/10.3390/molecules31081363 - 21 Apr 2026

Cited by 1 | Viewed by 498

Abstract

The decline of fossil fuel resources and the negative impact of fuel combustion on the environment are forcing scientists to develop new technologies for producing functional carbon materials with various useful properties. This work is devoted to a detailed study of the transformations [...] Read more.

The decline of fossil fuel resources and the negative impact of fuel combustion on the environment are forcing scientists to develop new technologies for producing functional carbon materials with various useful properties. This work is devoted to a detailed study of the transformations of monosaccharides, glucose and levoglucosan, during hydrothermal carbonization, aimed at the formation of carbon microspheres. Hydrochars were obtained at temperatures of 200, 250, and 300 °C and characterized using SEM, Py-GC/MS, and elemental analysis. Changes in the chemical composition of the liquid phase were studied, depending on the HTC temperature and precursor concentration. Expanded knowledge of microsphere formation enriches information on the mechanism of monosaccharide transformation for the production of new carbon materials through synthesis from inexpensive precursors. Full article

(This article belongs to the Section Materials Chemistry)

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17 pages, 1658 KB

Open AccessArticle

Effects of Cu Doping on the Microstructure, Room-Temperature Desulfurization Performance and Reaction Mechanism of Nano-ZnO

by Yue Gao, Chunhong Shao, Xuan Qi, Junfeng Zhang and Xingqian Liu

Molecules 2026, 31(8), 1362; https://doi.org/10.3390/molecules31081362 - 21 Apr 2026

Viewed by 493

Abstract

A nano-CuO/ZnO desulfurizer was successfully prepared via a homogeneous precipitation method, and the effects of Cu doping on its microstructure, oxygen species, desulfurization performance, and reaction mechanism were systematically investigated. The results show that an appropriate Cu doping amount (TZ2, Cu:Zn = 1:18.40) [...] Read more.

A nano-CuO/ZnO desulfurizer was successfully prepared via a homogeneous precipitation method, and the effects of Cu doping on its microstructure, oxygen species, desulfurization performance, and reaction mechanism were systematically investigated. The results show that an appropriate Cu doping amount (TZ2, Cu:Zn = 1:18.40) significantly reduces the particle size (to ~10.9 nm) compared with pure ZnO (14.3 nm), leading to an increased number of surface-active sites. XPS and TG analyses reveal that Cu incorporation increases the proportion of lattice oxygen and decreases the concentration of oxygen vacancies, indicating that the modification effect of Cu dominates over the particle size effect in regulating surface oxygen species. Despite the reduced oxygen vacancy concentration, the desulfurization performance is markedly enhanced, with TZ2 exhibiting the longest breakthrough time under oxygen-free conditions at room temperature. This improvement is attributed to the strong interaction between highly dispersed Cu species and the ZnO matrix, which promotes H₂S adsorption and activation. Mechanistic studies demonstrate that, unlike pure nano-ZnO, where oxygen vacancy-mediated reactions dominate, the CuO/ZnO system follows a chemisorption-driven pathway involving the formation of copper sulfides and highly reactive polysulfide intermediates. Furthermore, the presence of oxygen significantly influences the reaction behavior, with an optimal oxygen concentration (~10%) maximizing desulfurization performance by balancing the generation of reactive oxygen species and sulfur intermediates. This work provides new insights into the design of high-performance ZnO-based desulfurizers and highlights the critical role of Cu-induced mechanism transformation. Full article

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16 pages, 4596 KB

Open AccessArticle

Efficient Photocatalytic Elimination of Imidazolinone Herbicides by Bismuth-Based Photocatalyst BiOIO₃

by Weili Yu, Yan Tian, Mengyu Guo, Shuping Tong, Chengshuai Li, Bingjie Zhang and Yongqiang Ma

Molecules 2026, 31(8), 1361; https://doi.org/10.3390/molecules31081361 - 21 Apr 2026

Viewed by 426

Abstract

Imidazolinone herbicides such as imazethapyr (IMT) pose potential ecological risks due to their high mobility and ecotoxicity. This study synthesized the bismuth-based photocatalyst BiOIO₃ via a facile hydrothermal method and systematically characterized its physicochemical properties. BiOIO₃ features a 2D lamellar structure, [...] Read more.

Imidazolinone herbicides such as imazethapyr (IMT) pose potential ecological risks due to their high mobility and ecotoxicity. This study synthesized the bismuth-based photocatalyst BiOIO₃ via a facile hydrothermal method and systematically characterized its physicochemical properties. BiOIO₃ features a 2D lamellar structure, pure phase composition, and a built-in internal polarization electric field that efficiently separates photogenerated electron–hole pairs. Photocatalytic experiments exhibited that BiOIO₃ achieved 84.5% elimination of IMT, with a rate constant 66 times higher than that of TiO₂ (Rutile). Mechanistic studies revealed that photogenerated electrons (e⁻), holes (h⁺), and superoxide radicals (·O₂⁻) are the primary reactive species. HPLC-MS/MS identified key intermediates, and QSAR-based toxicity prediction showed reduced mutagenicity for most intermediates. Importantly, BiOIO₃ effectively eliminated five imidazolinone herbicides simultaneously. This work highlights BiOIO₃ as a promising photocatalyst for efficient and practical remediation of imidazolinone herbicide-contaminated water. Full article

(This article belongs to the Section Photochemistry)

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30 pages, 16343 KB

Open AccessReview

Modulatory Effects of Bioactive Phytoconstituents on the Amplitude and Gating Properties of Membrane Ion Channels

by Sheng-Nan Wu, Guglielmina Froldi, Ya-Jean Wang and Rasa Liutkevičienė

Molecules 2026, 31(8), 1360; https://doi.org/10.3390/molecules31081360 - 21 Apr 2026

Viewed by 895

Abstract

This review provides a comprehensive overview of the modulatory actions of plant-derived constituents on membrane ion channels in various cell types. Among their diverse bioactivities, ion channel regulation—governing membrane excitability, signal transduction, and cellular homeostasis—has emerged as a critical mechanistic basis for their [...] Read more.

This review provides a comprehensive overview of the modulatory actions of plant-derived constituents on membrane ion channels in various cell types. Among their diverse bioactivities, ion channel regulation—governing membrane excitability, signal transduction, and cellular homeostasis—has emerged as a critical mechanistic basis for their pharmacological effects. Twenty-four representative phytoconstituents are discussed and classified into five major categories based on their structural features: alkaloids, terpenoids, lignans and acetogenins, polyphenols, and other aromatic and conjugated compounds. Across these categories, the reviewed compounds exhibit distinct and often highly specific effects on the amplitude and gating kinetics of multiple ionic currents, including voltage-gated Na⁺ currents (I_Na), delayed-rectifier K⁺ currents (I_K(DR)), M-type K⁺ currents (I_K(M)), hyperpolarization-activated cation currents (I_h), erg-mediated K⁺ currents (I_K(erg)), inwardly rectifying K⁺ currents, and Ca²⁺-activated K⁺ currents (I_K(Ca)). Alkaloids predominantly suppress voltage-gated K⁺ currents, with notable exceptions such as aconitine, which alters the properties of both I_Na and I_K(DR), thereby contributing to its proarrhythmic toxicity. Terpenoids, including cannabidiol, croton diterpenoids, lutein, thymol, and triptolide, exert multifaceted effects on I_K(M), I_h, inwardly rectifying K⁺ currents, and Ca²⁺-activated K⁺ channels. Lignans and acetogenins, such as gomisin A, honokiol, sesamin, and squamocin, primarily modulate I_Na, I_h, and I_K(Ca), with several compounds demonstrating strong links between ion-channel modulation and anti-neoplastic or neuroprotective actions. Polyphenolic compounds, including curcumin, eugenol, resveratrol, gastrodigenin, gastrodin, and pterostilbene, display diverse ion-channel targeting profiles, influencing multiple Na⁺ and K⁺ channel subtypes. Other aromatic or conjugated compounds, such as isoplumbagin, plumbagin, and verteporfin, regulate I_K(erg) and I_K(Ca), potentially contributing to both therapeutic efficacy and adverse effects. Collectively, the compound-specific modulation of current amplitude and gating kinetics offers valuable mechanistic insight into the pharmacological and toxicological significance of plant-derived natural products, highlighting the functional role of ion channel evaluation in guiding their therapeutic development and ensuring safety assessment. Full article

(This article belongs to the Special Issue Bioactivity of Natural Compounds: From Plants to Humans, 2nd Edition)

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1 pages, 132 KB

Open AccessRetraction

RETRACTED: Atta et al. Application of Super-Amphiphilic Silica-Nanogel Composites for Fast Removal of Water Pollutants. Molecules 2016, 21, 1392

by Ayman M. Atta, Hamad A. Al-Lohedan, Ahmed M. Tawfik and Abdelrahman O. Ezzat

Molecules 2026, 31(8), 1359; https://doi.org/10.3390/molecules31081359 - 21 Apr 2026

Viewed by 354

Abstract

The Journal retracts the article “Application of Super-Amphiphilic Silica-Nanogel Composites for Fast Removal of Water Pollutants” [...] Full article

28 pages, 1388 KB

Open AccessReview

Flavor Scalping in Packaged Foods: A Review

by Michael G. Kontominas

Molecules 2026, 31(8), 1358; https://doi.org/10.3390/molecules31081358 - 21 Apr 2026

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Abstract

Over the past decades, plastics have been increasingly employed to package foods and beverages. Furthermore, foods, nowadays, are kept in contact with plastics for far longer periods than ever before. A number of conventional polymers, i.e., polyethylene (PE), Polypropylene (PP), Ethylene Vinyl Acetate [...] Read more.

Over the past decades, plastics have been increasingly employed to package foods and beverages. Furthermore, foods, nowadays, are kept in contact with plastics for far longer periods than ever before. A number of conventional polymers, i.e., polyethylene (PE), Polypropylene (PP), Ethylene Vinyl Acetate (EVA), Εthylene vinyl alcohol (EVOH) polystyrene (PS), Polyvinyl chloride (PVC), Polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), Polycarbonate (PC), polyethylene naphthalate (PEN), Polyamides (PAs), Polyacrylonitrile (PAN) as well as biodegradable polymers-[Polylactide (PLA)] are used commercially in food packaging applications. Potential interaction of food with the packaging container includes: permeation, migration and flavor scalping. Most food and beverage containers are lined with plastics mainly polyolefins, which due to their low polarity tend to absorb volatile compounds of similar polarity. Absorption of flavor compounds by polymers involves both partitioning and diffusion through the plastic. Absorption is influenced by (i) polymer properties such as polarity, morphology, glass transition temperature, density, free volume, crystallinity and surface area, (ii) flavor compound properties such as structure, concentration, and polarity, and (iii) external factors such as temperature, time of contact, relative humidity and the proximity of other compounds. Based on the above, it is apparent that flavor scalping should be among one of the food packaging industry priorities in order to efficiently preserve the quality of packaged food flavor. This review highlights the various factors affecting the scalping process, as well as the consequences of flavor scalping in various food and beverage commodities. The review covers the period 1990–2925 and used the LitChemPlast data base for literature search. Full article

(This article belongs to the Special Issue Flavor Scalping)

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15 pages, 1856 KB

Open AccessArticle

Application of Eutectic-Solvent-Based Liquid–Liquid Microextraction for Removal of Eight Bisphenols from Water and Industrial Samples

by Michal Adámek, Petr Tůma and Zuzana Bosáková

Molecules 2026, 31(8), 1357; https://doi.org/10.3390/molecules31081357 - 21 Apr 2026

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Abstract

In this study, new types of eutectic solvents (ESs) are tested for their ability to remove the eight most common bisphenols (BPA, BPB, BPC, BPE, BPF, BPG, BPS, BPAP), which are environmentally monitored substances, from aqueous matrices. A total of 18 ESs based [...] Read more.

In this study, new types of eutectic solvents (ESs) are tested for their ability to remove the eight most common bisphenols (BPA, BPB, BPC, BPE, BPF, BPG, BPS, BPAP), which are environmentally monitored substances, from aqueous matrices. A total of 18 ESs based on hydrophobic organic acids, such as capric, caprylic, lauric, and myristic acids, and terpenes, such as DL-menthol, terpineol, linalool, and geraniol, are prepared and mixed in various molar ratios. The highest extraction yield for all types of BPs is achieved with a binary mixture of geraniol:caprylic acid prepared in a molar ratio of 1:1. This ES can be used repeatedly for five consecutive cycles achieving almost 100% recovery for BPB, BPC, BPG, and BPAP, while for BPA, BPE, and BPF, the yield drops to 97% and for BPS to 90%. The efficiency of ES extraction is verified using HPLC-MS/MS to determine the BPs in the aqueous phase. This is performed at a pentafluorophenylpropyl stationary phase with LOQs ranging from 0.24 to 29.1 ng/mL. The applicability of this HPLC-MS/MS method was demonstrated by monitoring the occurrence of BPs in thermal paper and other industrial samples. Full article

(This article belongs to the Special Issue Analytical Methods for Food and Environmental Pollutants: Current and Future Perspectives, 2nd Edition)

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13 pages, 1351 KB

Open AccessArticle

Chemical Composition of Eriodictyon californicum (California Yerba Santa) Cultivated in Ontario, Oregon, USA

by Clinton C. Shock, Ambika Poudel, Prabodh Satyal, Jianping Zhao, Joseph Lee, Mei Wang and William N. Setzer

Molecules 2026, 31(8), 1356; https://doi.org/10.3390/molecules31081356 - 21 Apr 2026

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Abstract

Leaves from California yerba santa (Eriodictyon californicum) have been used historically by indigenous peoples for medicinal purposes. Recent research has ascribed potential pharmaceutical effects to leaf polyphenols, without a consideration of other constituents. Based on prior analyses of polyphenols in leaves [...] Read more.

Leaves from California yerba santa (Eriodictyon californicum) have been used historically by indigenous peoples for medicinal purposes. Recent research has ascribed potential pharmaceutical effects to leaf polyphenols, without a consideration of other constituents. Based on prior analyses of polyphenols in leaves sampled in nature, five accessions known to be rich in sterubin and five accessions known to be rich in eriolic acid C were grown from seeds in Ontario, Oregon, and samples of their leaves were harvested and evaluated for their essential oil and polyphenol contents. The major essential oil components in E. californicum were 1,8-cineole (0.6–35.5%), (Z)-β-ocimene (6.8–15.7%), terpinen-4-ol (8.3–16.1%), α-pinene (2.6–13.6%), β-phellandrene (1.9–11.7%), γ-terpinene (4.6–7.9%), ethyl (E)-cinnamate (0.2–8.9%), α-terpineol (1.5–5.2%), p-cymene (2.0–5.3%), and β-pinene (0.6–6.8%). Fifteen polyphenols with a prominence of eriolic acid C, rosmarinic acid, sterubin, homoeriodictyol, 6-methoxynaringenin, hesperetin, and eriodictyol were identified. Essential oils may contribute to the medicinal properties of the leaves of California yerba santa. Results from the ten samples were evaluated for both polyphenols and essential oils; the variations in several essential oils may be correlated to variations in some of the polyphenols. Full article

(This article belongs to the Special Issue Chemical Composition and Biological Activity of Essential Oils and Other Extracts: From Extraction to Application, Second Edition)

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17 pages, 5715 KB

Open AccessArticle

The Effects and Molecular Mechanisms of a Peptide from Periplaneta americana L. in Skin Wound Healing

by Honghong Qiu, Yanyan Chen, Wei Zhang, Bin Dong, Dongli Zhang, Renjin Tang and Zhong Liu

Molecules 2026, 31(8), 1355; https://doi.org/10.3390/molecules31081355 - 21 Apr 2026

Viewed by 782

Abstract

Periplaneta americana extract can promote wound healing and may play an important role in skin wound healing. In this study, we identified a peptide (DL-13) from Periplaneta americana L. and explored its role and mechanisms in skin wound healing. In vitro, the effects [...] Read more.

Periplaneta americana extract can promote wound healing and may play an important role in skin wound healing. In this study, we identified a peptide (DL-13) from Periplaneta americana L. and explored its role and mechanisms in skin wound healing. In vitro, the effects of DL-13 on proliferation, migration, and related gene/protein expression in HaCaT keratinocytes were assessed via qRT-PCR and Western blot. In vivo, rat wound healing assays confirmed its efficacy. Results showed DL-13 accelerated rat wound healing. In in vitro studies, DL-13 activated EGFR and its downstream PI3K/AKT/mTOR, ERK/MAPK, and JAK2/STAT3 pathways, upregulated EMT-related proteins (N-cadherin, MMP-2, p-FAK, β-catenin), partially regulated macrophage cytokine secretion, and promoted HaCaT proliferation/migration, thereby facilitating re-epithelialization at skin injury sites. Overall, DL-13 may enhance the function of HaCaT cells by activating the EGFR signaling pathway and regulate inflammatory factors in macrophages, thereby promoting the healing of skin wounds in rats. The results of this study will lay an experimental and scientific foundation for the discovery of new compounds for wound healing and their application. Full article

(This article belongs to the Special Issue Advances in Application of Natural Compounds in Skin Repair and Regenerative Medicine)

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13 pages, 1817 KB

Open AccessArticle

Improvement of Cs₃Cu₂I₅ Single-Crystal Growth Process by YCl₃ Additives: Cu⁺ Oxidation Inhibition and Precursor Colloid Stabilization

by Wang Zhou, Tianyun Du, Chunqian Xu and Xiuxun Han

Molecules 2026, 31(8), 1354; https://doi.org/10.3390/molecules31081354 - 20 Apr 2026

Viewed by 681

Abstract

Cs₃Cu₂I₅ single crystals are regarded as promising next-generation scintillators due to their large Stokes shift and low self-absorption characteristics. However, the cost-effective solution growth method faces critical challenges: the instability of colloidal precursors in solutions and the severe [...] Read more.

Cs₃Cu₂I₅ single crystals are regarded as promising next-generation scintillators due to their large Stokes shift and low self-absorption characteristics. However, the cost-effective solution growth method faces critical challenges: the instability of colloidal precursors in solutions and the severe oxidation of Cu⁺ during crystal growth. This study innovatively introduces yttrium chloride (YCl₃) as a dual-functional additive to address both issues simultaneously. The hydrolysis of YCl₃ creates a controlled acidic environment, effectively suppressing the oxidation of Cu⁺; meanwhile, it enhances the stability of colloidal precursors by significantly increasing their surface charge and narrowing the particle size distribution. These synergistic effects enable the rapid growth (approximately 100 h) of near-centimeter-sized Cs₃Cu₂I₅ single crystals with high crystallinity, without the need for inert gas protection. The optimized crystals exhibit exceptional performance: a photoluminescence quantum yield (PLQY) of 93.22% ± 0.47%, a scintillation decay time of 210.04 ns, and a light yield of ~738.14 pe/MeV. This YCl₃-mediated growth strategy establishes an efficient approach for the solution-based synthesis of high-quality Cs₃Cu₂I₅ single crystals, holding great significance for advancing high-sensitivity, environment-stable radiation detection applications such as medical diagnostics and nuclear safety monitoring. Full article

(This article belongs to the Special Issue Nanochemistry in Asia)

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49 pages, 2496 KB

Open AccessReview

Probiotics and Fermented Foods in Human Nutrition

by Irene Dini

Molecules 2026, 31(8), 1353; https://doi.org/10.3390/molecules31081353 - 20 Apr 2026

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Abstract

Fermented foods and probiotics represent complementary yet distinct components of human nutrition. Fermented foods are shaped by biochemical transformations driven by microbial metabolism, whereas probiotics are live microorganisms that may confer health benefits to the host. In both cases, bacteria, yeasts, and filamentous [...] Read more.

Fermented foods and probiotics represent complementary yet distinct components of human nutrition. Fermented foods are shaped by biochemical transformations driven by microbial metabolism, whereas probiotics are live microorganisms that may confer health benefits to the host. In both cases, bacteria, yeasts, and filamentous fungi mediate key metabolic activities that generate bioactive compounds and modulate host–microbiota interactions. During fermentation, microbial communities synthesize organic acids, peptides, exopolysaccharides, vitamins, and other metabolites that enhance food safety, sensory attributes, and potential health-promoting properties. Several microbial products, such as bacteriocins, reuterin, hydroxylated fatty acids, and exopolysaccharides, exhibit antimicrobial, immunomodulatory, antioxidant, and cholesterol-lowering activities. Advancing our understanding of microbial metabolism in fermented foods is essential for developing next-generation functional foods and nutraceuticals that leverage microbial biotransformations to support human health. Nonetheless, multiple challenges limit the translation of these advances into commercial products. Inadequately controlled fermentation may introduce microbiological or chemical hazards, regulatory frameworks governing microbial use in foods remain insufficiently defined, and standardized procedures for microbial strain handling and characterization are still lacking. This narrative review integrates current evidence on the nutraceutical properties of fermented foods and probiotics, while also examining the associated safety considerations and the technological factors that influence fermentation processes. Full article

(This article belongs to the Special Issue Bioactive Compounds in Foods and Their By-Products)

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16 pages, 884 KB

Open AccessArticle

Ultrasound-Assisted Extraction of Apple Pomace: Statistical Optimization and Antioxidant Activity Evaluation

by Magdalena Korol, Anna Łętocha, Małgorzata Tabaszewska, Łukasz Skoczylas and Elżbieta Sikora

Molecules 2026, 31(8), 1352; https://doi.org/10.3390/molecules31081352 - 20 Apr 2026

Viewed by 594

Abstract

Apple pomace, produced by the apple processing industry, is a raw material rich in bioactive compounds with a broad spectrum of biological activity, yet it remains underutilized. Both the method of raw material stabilization and the extraction technique influence the quality of the [...] Read more.

Apple pomace, produced by the apple processing industry, is a raw material rich in bioactive compounds with a broad spectrum of biological activity, yet it remains underutilized. Both the method of raw material stabilization and the extraction technique influence the quality of the final apple pomace extract. The aim of this study was to select the most effective stabilization method and to determine optimal conditions for ultrasound-assisted extraction (UAE) of total phenolic compounds (TPC) from apple pomace. The extraction process was optimized using mathematical methods of experimental design. Input parameters included extraction temperature and time, solvent composition (ethanol concentration), and the raw material-to-solvent mass ratio. Output variables included total phenolic content and antioxidant activity of the extracts. Total phenolic content was determined using the Folin–Ciocalteu method, and antioxidant activity was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The conditions enabling maximum extraction of phenolic compounds (total phenolic content: 8.207 mg GAE/mL and 88.09% DPPH inhibition) were achieved at 90 min, a temperature of 45 °C, an ethanol concentration of 50%, and a raw material-to-solvent ratio of 8 g. Full article

(This article belongs to the Special Issue Multifunctional Natural Ingredients in Skin Protection and Care, 2nd Edition)

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24 pages, 988 KB

Open AccessReview

Plant Bioactive Compounds at the Interface of Extraction Science, Green Nanoparticles and Applied Biotechnology: A Narrative Review

by Cristina-Ștefania Gălbău, Lorena Dima, Andrea Elena Neculau, Marius Irimie, Lea Pogačnik da Silva, Oana Bianca Oprea, Liviu Gaceu and Mihaela Badea

Molecules 2026, 31(8), 1351; https://doi.org/10.3390/molecules31081351 - 20 Apr 2026

Cited by 1 | Viewed by 901

Abstract

In the contemporary era, nanotechnology has become a central pillar in numerous domains, particularly in cosmetics, nanoelectronics, nanomedicine, and nanobiotechnology. Defined by its focus on materials with dimensions ranging from 0.1 to 100 nm, nanotechnology offers unique physicochemical properties—such as enhanced reactivity, conductivity, [...] Read more.

In the contemporary era, nanotechnology has become a central pillar in numerous domains, particularly in cosmetics, nanoelectronics, nanomedicine, and nanobiotechnology. Defined by its focus on materials with dimensions ranging from 0.1 to 100 nm, nanotechnology offers unique physicochemical properties—such as enhanced reactivity, conductivity, and permeability—attributable to the nanoscale. These properties facilitate greater interaction with biological systems, notably improving cellular uptake and functional efficacy. The increasing demand for eco-friendly and biocompatible nanomaterials has driven interest in green synthesis routes, particularly those utilising plant extracts. These methods stand out due to their low toxicity and environmental impact, positioning it as a safer alternative to conventional chemical or microbial methods. Plant-extract-mediated nanoparticles demonstrate promising applications in diagnostics, drug delivery, regenerative medicine, and neurotherapeutics. Their role in precision medicine, including gene and drug delivery and the imaging of neurological disorders, underscores green nanotechnology’s transformative potential. This review highlights recent advances in the synthesis, functionality, and biomedical applications of plant-based nanoparticles, emphasizing their relevance in in vitro models and prospective clinical settings. Full article

(This article belongs to the Special Issue Bioactive Compounds in Plants: Extraction and Application)

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12 pages, 1038 KB

Open AccessArticle

Berberine Toxicity Profile in Experimental Models as a Basis for Assessing Its Biological Safety

by Anna Karczmarzyk, Danuta Wojcieszyńska, Agnieszka Nowak, Wojciech Smułek and Urszula Guzik

Molecules 2026, 31(8), 1350; https://doi.org/10.3390/molecules31081350 - 20 Apr 2026

Viewed by 958

Abstract

Berberine, a natural alkaloid, is a substance widely used in natural medicine. However, there is a significant knowledge gap regarding the potential negative effects of higher environmental concentrations of berberine resulting from its use as a supplement. Therefore, the aim of this study [...] Read more.

Berberine, a natural alkaloid, is a substance widely used in natural medicine. However, there is a significant knowledge gap regarding the potential negative effects of higher environmental concentrations of berberine resulting from its use as a supplement. Therefore, the aim of this study was to assess its toxicity towards microorganisms and organisms from various trophic levels. The results indicate that berberine may influence the reorganization of bacterial membranes, thereby negatively impacting the environmental microbiome. However, oxidative cell damage, a phenomenon commonly described in the literature, was not demonstrated. At the concentrations used, berberine may even have a protective effect. The analysis of toxicity towards Tetrahymena, Selenastrum, and Heterocypris indicated a similar level of berberine toxicity across these organisms, suggesting that the toxic effect is not species-dependent and that the mechanism of toxicity is probably based on universal cellular mechanisms. Full article

(This article belongs to the Special Issue Degradation of Aromatic Compounds in the Environment)

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17 pages, 1907 KB

Open AccessArticle

Geochemical Fractionation and Environmental Risk Assessment of Potentially Toxic Elements in Copper Flotation Tailings from Tongling, Anhui Province

by Yunhu Hu, Shuwen Xue, Mu You and Hongxia Fang

Molecules 2026, 31(8), 1349; https://doi.org/10.3390/molecules31081349 - 20 Apr 2026

Viewed by 597

Abstract

Copper flotation tailings are produced in large quantities during ore beneficiation and smelting, yet remain underutilized and can act as persistent sources of potentially toxic elements. Here, we combined XRD-based mineralogical characterization, ICP-OES quantification, Tessier sequential extraction, and pH-dependent batch leaching to elucidate [...] Read more.

Copper flotation tailings are produced in large quantities during ore beneficiation and smelting, yet remain underutilized and can act as persistent sources of potentially toxic elements. Here, we combined XRD-based mineralogical characterization, ICP-OES quantification, Tessier sequential extraction, and pH-dependent batch leaching to elucidate metal occurrence, mobility, and associated ecological risk in tailings from Tongling, Anhui Province. This study systematically analyzed the mineral composition, potentially toxic elements content, chemical fractions, leaching behavior, and ecological risks of copper flotation tailings from the Shuimuchong tailings reservoir in Tongling, Anhui Province. XRD and XRF analyses revealed that calcite, quartz, and garnet were dominant mineral phases in the tailings. Elevated levels of Cu, Cd, Pb, Zn, and As were detected, some of which surpassed both local background concentrations and national soil quality standards. Most potentially toxic elements primarily existed in the residual fraction, indicating low mobility. Leaching experiments revealed that Zn, Cu, and As showed enhanced release under acidic conditions, making them priority risk elements during tailings acidification. Pollution index and ecological risk assessments indicated that the tailings were heavily contaminated, with Cu and Cd as the main risk contributors. The Risk Assessment Code (RAC) evaluation showed that Cd had the highest bioavailability and ecological risk. By clarifying the behavior of pollutants, this study contributes to the effective regulation of environmental hazards and the sustainable use of tailing materials. Full article

(This article belongs to the Section Analytical Chemistry)

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28 pages, 4145 KB

Open AccessArticle

GC-MS Analysis of Volatile Differences in Rice and Qingke Noodles Formulated with Functional Root Plant Flours

by Essam ElShamey, Jiazhen Yang, Jiachun Jiang, Xiaoying Pu, Li Xia, Li’e Yang, Xiaomeng Yang and Yawen Zeng

Molecules 2026, 31(8), 1348; https://doi.org/10.3390/molecules31081348 - 20 Apr 2026

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Abstract

The integration of rooted plant flour into traditional noodle matrices, such as rice noodles and qingke noodles, represents a novel approach to enhancing the nutritional and sensory profiles of staple foods. This study investigates the volatile flavor components and functional compounds derived from [...] Read more.

The integration of rooted plant flour into traditional noodle matrices, such as rice noodles and qingke noodles, represents a novel approach to enhancing the nutritional and sensory profiles of staple foods. This study investigates the volatile flavor components and functional compounds derived from rooted plant flours, including Gongmi “tribute rice”, qingke “highland barley” flour, kudzu vine flour, Gastrodia elata blume flour, dried ginger flour, and fishwort root flour, when incorporated into rice and qingke noodles. The novelty of this research lies in its comprehensive analysis of how these flours influence not only the nutritional and textural properties but also the volatile organic compounds (VOCs) that define sensory acceptance and health benefits. Using advanced gas chromatography mass spectrometry (GC-MS), we identified key VOCs, such as esters, aldehydes, and terpenes, which contribute to unique flavor profiles like umami, sweetness, and earthy notes in fortified noodles. Additionally, the study highlights the best functional compounds for health, including polyphenols, resistant starch, and polysaccharides, which demonstrate significant antioxidants, anti-inflammatory, and cholesterol-lowering properties. For instance, highland barley enriched flour exhibited high levels of phenolic compounds and carotenoids, which correlated with improved antioxidant activity and a reduced glycemic index. Similarly, Gongmi flour contributed elevated levels of γ-aminobutyric acid (GABA) and rutin, enhancing the rice noodles’ potential to manage metabolic diseases and support cardiovascular health. Molecular docking analyses predicted strong interactions between key volatile compounds (e.g., 3-dihydro-1, 3-trimethyl-33-phenyl-1H-indene) and metabolic targets like ACE and SGLT1, suggesting mechanisms for their cardioprotective and anti-diabetic effects. This research provides a groundbreaking framework for developing next generation functional foods by leveraging rooted plant flours to bridge the gap between sensory appeal and health efficacy, offering strategic insights for personalized nutrition and sustainable food production. Full article

(This article belongs to the Special Issue 30th Anniversary of Molecules—Recent Advances in Food Chemistry)

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18 pages, 1882 KB

Open AccessArticle

Integrated Bacillus subtilis Pretreatment, Chlorella vulgaris Cultivation, and Trichoderma viride Bioflocculation for Enhanced Municipal Wastewater Remediation and Biodiesel Production

by Hongzhi Chen, Xiuren Zhou and Guifang Xu

Molecules 2026, 31(8), 1347; https://doi.org/10.3390/molecules31081347 - 20 Apr 2026

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Abstract

Municipal wastewater represents an underutilized secondary biomass resource rich in organic carbon and nutrients that can be valorized through biotechnological conversion. In this study, we developed an integrated multi-microbial biorefinery platform to transform municipal wastewater into value-added biofuel via sequential bacterial treatment, microalgal [...] Read more.

Municipal wastewater represents an underutilized secondary biomass resource rich in organic carbon and nutrients that can be valorized through biotechnological conversion. In this study, we developed an integrated multi-microbial biorefinery platform to transform municipal wastewater into value-added biofuel via sequential bacterial treatment, microalgal biomass generation, and fungal-assisted harvesting. Wastewater was first pretreated with Bacillus subtilis to enzymatically hydrolyze complex organic substrates and enrich the medium with bioactive metabolites, including auxins and gibberellins. The conditioned wastewater was subsequently used to cultivate Chlorella vulgaris, followed by biomass recovery using Trichoderma viride pellets as a sustainable bioflocculant. The integrated consortium significantly enhanced nutrient removal efficiency and promoted algal biomass accumulation, lipid enrichment, and biodiesel productivity compared to monoculture controls. Elevated hydrolytic enzyme activities (cellulase, protease, and amylases) facilitated organic matter conversion into bioavailable substrates, while increased phytohormone levels stimulated algal growth and lipid biosynthesis. Additionally, fungal bioflocculation substantially improved biomass recovery efficiency, reducing the need for energy-intensive harvesting technologies. This work highlights the potential of a biotechnology-driven approach for integrating wastewater remediation with biofuel production. By integrating microbial metabolism, enzymatic transformation, and sustainable separation processes, the proposed biorefinery system suggests a potentially low-carbon approach for simultaneous environmental remediation and biomass valorization, although further life cycle and energy balance analyses are required to validate this aspect. Full article

(This article belongs to the Special Issue Biotechnology and Biomass Valorization)

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23 pages, 4855 KB

Open AccessArticle

Cholinesterase Inhibitory Activity of Alkylated Quinobenzothiazinium Salts

by Sarka Stepankova, Andrzej Bak, Malgorzata Latocha, Violetta Kozik, Agata Kawulok, Josef Jampilek and Andrzej Zieba

Molecules 2026, 31(8), 1346; https://doi.org/10.3390/molecules31081346 - 19 Apr 2026

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Abstract

Ten substituted quinobenzothiazinium salts were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). All the compounds inhibited AChE in the IC₅₀ range of 0.03–0.658 µM, with 5,8,10-trimethyl-12H-quinolino[3,4-b][1,4]benzothiazin-5-ium chloride (3d) being the most potent [...] Read more.

Ten substituted quinobenzothiazinium salts were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). All the compounds inhibited AChE in the IC₅₀ range of 0.03–0.658 µM, with 5,8,10-trimethyl-12H-quinolino[3,4-b][1,4]benzothiazin-5-ium chloride (3d) being the most potent inhibitor, with an IC₅₀ value significantly better than that of the clinically used rivastigmine and galantamine and comparable to that of tacrine and donepezil. The IC₅₀ values for BChE inhibition ranged from 0.34 to 4.25 µM; 5,9-dimethyl-12H-quinolino[3,4-b][1,4]benzothiazin-5-ium chloride (3b) exhibited the strongest BChE inhibitory activity and in general, all the investigated compounds were more potent inhibitors than rivastigmine and galantamine. Based on the calculated selectivity index values, they are rather preferential inhibitors of AChE. Cytotoxicity tests performed on normal human dermal fibroblasts (HFF-1) did not demonstrate any significant cytotoxicity under the tested conditions. The distance-oriented structure distribution for the studied molecules was related with the activity data using principal component analysis and hierarchical clustering analysis. (SAR)-based evaluation is reported to predict activity cliffs using a similarity–activity landscape index for the AChE inhibitory response values. Moreover, direct protein-mediated in silico methods were utilized to identify factors that may be relevant for quantitative (Q)SAR modeling. In practice, target-oriented molecular docking was used to organize the spatial distribution of the ligand property space for the anti-AChE system. In general, this series of alkylated quinobenzothiazinium salts with potent inhibitory activity against cholinesterases fulfills Lipinski’s rule of five based on in silico predictions and is also expected to have high absorption in the human gastrointestinal tract. All active derivatives are also expected to penetrate the blood–brain barrier, making them promising compounds for further research and possible use in Alzheimer’s disease therapy. Full article

(This article belongs to the Special Issue Quinoline System in Design and Synthesis of New Bioactive Agents)

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42 pages, 4403 KB

Open AccessReview

A Review of Catalysts for Hydrogen Production from Methanol

by Eun Duck Park

Molecules 2026, 31(8), 1345; https://doi.org/10.3390/molecules31081345 - 19 Apr 2026

Viewed by 1056

Abstract

Methanol is the simplest C1 oxygenated compound possessing the highest hydrogen-to-carbon ratio and can therefore be used as an effective hydrogen carrier. Furthermore, it can be easily transported by land and sea because it is liquid at room temperature and atmospheric pressure. Methanol [...] Read more.

Methanol is the simplest C1 oxygenated compound possessing the highest hydrogen-to-carbon ratio and can therefore be used as an effective hydrogen carrier. Furthermore, it can be easily transported by land and sea because it is liquid at room temperature and atmospheric pressure. Methanol can be converted into hydrogen via methanol steam reforming (MSR), aqueous-phase reforming of methanol (APRM), or aqueous methanol dehydrogenation (AMDH). In this review, various catalysts for MSR, APRM, and AMDH are summarized. Highly active and stable catalysts that can operate under low steam-to-methanol ratios are needed to increase the economics of the MSR process. Compared with the MSR process, the APRM process is rather simple because the water–gas shift reaction can occur simultaneously; however, more constraints exist in the selection of active metals and supports to ensure high activity and stability under APRM conditions. The inherently low reaction rate compared to MSR and the structural vulnerability of the catalyst under severe hydrothermal conditions are obstacles that the APRM catalysts must overcome. The low intrinsic catalytic activity and the high cost of homogeneous catalysts represent fundamental limitations inherent to AMDH catalysts. Based on a literature survey of MSR, APRM, and AMDH catalysts, some future research directions are also discussed. Full article

(This article belongs to the Special Issue Advances in Heterogeneous Catalysis for Green Chemistry)

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28 pages, 1120 KB

Open AccessArticle

SO₂ Management and Yeast Inoculation Strategies (NoSO₂-Spont, NoSO₂Sc, SO₂Sc) During Fermentation Shape the Chemical, Polyphenolic, Microbiological, and Sensory Profiles of ‘Solaris’ White Wine

by Magdalena Błaszak, Ireneusz Ochmian, Ireneusz Kapusta and Sabina Lachowicz-Wiśniewska

Molecules 2026, 31(8), 1344; https://doi.org/10.3390/molecules31081344 - 19 Apr 2026

Viewed by 585

Abstract

Consumer interest in low-SO₂ white wines is increasing; however, such approaches may reduce compositional and sensory predictability. This study evaluates how three fermentation strategies—SO₂ addition and Saccharomyces cerevisiae ES181 inoculation (SO₂Sc), spontaneous fermentation (NoSO₂-Spont), and inoculation with [...] Read more.

Consumer interest in low-SO₂ white wines is increasing; however, such approaches may reduce compositional and sensory predictability. This study evaluates how three fermentation strategies—SO₂ addition and Saccharomyces cerevisiae ES181 inoculation (SO₂Sc), spontaneous fermentation (NoSO₂-Spont), and inoculation with S. cerevisiae ES181 without SO₂ addition (NoSO₂Sc)—shape the chemical profile, polyphenolic composition, colour, microbiological status, and sensory perception of ‘Solaris’ wines relative to the must (reference). A single batch of ‘Solaris’ must (one press run) was split into three variants and fermented under identical temperature conditions (12 ± 0.5 °C), followed by cool ageing and natural sedimentation prior to bottling. Basic oenological parameters, selected fermentation by-products, viable yeast counts, CIE Lab colour, targeted polyphenolics (phenolic acids, flavonols, flavan-3-ols, and stilbenes), PCA of by-products, and blind sensory evaluation were assessed. The NoSO₂-Spont variant showed reduced fermentation completeness (higher residual sugars and lower ethanol) and the highest volatile acidity, together with elevated glycerol and several higher alcohols, and received the lowest sensory ratings. The SO₂Sc variant yielded the most controlled outcome, with the lowest volatile acidity, the brightest colour (higher L*, lower b*), and the highest sensory acceptance. The NoSO₂Sc variant produced intermediate sensory scores and a higher total phenolic content; however, volatile acidity remained high and viable yeast counts were the greatest, indicating increased susceptibility to microbiological activity during extended pre-bottling handling. Overall, the SO₂Sc strategy provides the greatest chemical stability and sensory acceptance, whereas low-SO₂ regimes require a hurdle approach (oxygen control, residual sugar management, hygiene, and stabilisation) to limit spoilage development and post-bottling refermentation. Full article

(This article belongs to the Special Issue Bioactive Food Compounds and Their Health Benefits)

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