Molecules

13 pages, 1177 KiB

Open AccessArticle

A Systematic Method for the Identification of Oligosaccharide Constituents in Polygonatum cyrtonema Hua Using UHPLC-Q-Exactive Orbitrap Mass Spectrometry

by Suyu Yang, Bowen Gao, Qingrui Yang, Yanghui Huo, Kailin Li, Liangyin Shu, Lingxuan Fan, Yiliang Liu, Huanting Li and Wei Cai

Molecules 2025, 30(7), 1433; https://doi.org/10.3390/molecules30071433 (registering DOI) - 24 Mar 2025

Abstract

A Polygonatum cyrtonema Hua (PCH) is a common medicinal and edible plant whose rhizomes are widely used for the treatment and prevention of various diseases. Previous studies have revealed a variety of chemical components such as polysaccharides, saponins, and flavonoids, which possess a [...] Read more.

A Polygonatum cyrtonema Hua (PCH) is a common medicinal and edible plant whose rhizomes are widely used for the treatment and prevention of various diseases. Previous studies have revealed a variety of chemical components such as polysaccharides, saponins, and flavonoids, which possess a variety of biological activities such as antimicrobial, lipid-regulating, anti-aging, hypoglycemic, and anti-inflammatory. However, to date, the structure and activity of its oligosaccharide components are still unclear. In this study, we developed a method combining ultra-high-performance liquid chromatography with Q-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap MS) and monosaccharide analysis for the identification of oligosaccharides in PCH. Finally, a total of 44 oligosaccharides, including 27 fructo-oligosaccharides (FOS), 10 arabino-oligosaccharides (AOS), and 7 others, were identified based on the precise relative molecular mass and fragment ion information provided by high-resolution mass spectrometry, in combination with standard comparison, monosaccharide composition analysis, and the relevant literature reports. All of those oligosaccharides were reported for the first time. These findings laid the foundation for the subsequent study of its medicinal substances and provided a theoretical basis for the more comprehensive development and utilization of PCH as a medicinal and edible product. Full article

(This article belongs to the Special Issue The Application of LC-MS in Pharmaceutical Analysis)

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14 pages, 2090 KiB

Open AccessArticle

The Effect of Polyethylene Terephthalate Nanoplastics on Amyloid-β Peptide Fibrillation

by Narmin Bashirova, Franziska Schölzel, Dominik Hornig, Holger A. Scheidt, Martin Krueger, Georgeta Salvan, Daniel Huster, Joerg Matysik and A. Alia

Molecules 2025, 30(7), 1432; https://doi.org/10.3390/molecules30071432 (registering DOI) - 24 Mar 2025

Abstract

Exposure of organisms to nanoplastics (NPs) is inevitable given their global abundance and environmental persistence. Polyethylene terephthalate (PET) is a common plastic used in a wide range of products, including clothing and food and beverage packaging. Recent studies suggest that NPs can cross [...] Read more.

Exposure of organisms to nanoplastics (NPs) is inevitable given their global abundance and environmental persistence. Polyethylene terephthalate (PET) is a common plastic used in a wide range of products, including clothing and food and beverage packaging. Recent studies suggest that NPs can cross the blood-brain barrier and cause potential neurotoxicity. It is widely known that aggregation of amyloid beta (Aβ) peptides in the brain is a pathological hallmark of Alzheimer’s disease (AD). While the impact of nanoplastics such as polystyrene (PS) on amyloid aggregation has been studied, the effects of PET NPs remain unexplored. In this study, we examined the effect of PET NPs of different sizes (PET_50nm and PET_140nm) and concentrations (0, 10, 50, and 100 ppm) on the fibrillation of Aβ_1-40. Our results showed that the presence of PET_50nm as well as PET_140nm decreased the lag phase of the fibrillation processes in a dose- and size-dependent manner from 6.7 ± 0.08 h for Aβ in the absence of PET (Aβ_control) to 3.1 ± 0.03 h for PET_50nm and 3.8 ± 0.06 h for PET_140nm. CD spectroscopy showed that PET_50nm significantly impacts the structural composition of Aβ aggregates. A significant rise in antiparallel β-sheet content and β-turn structure and a substantial reduction in other structures were observed in the presence of 100 ppm PET_50nm. These changes indicate that higher concentrations (100 ppm) of PET_50nm promote more rigid and uniform peptide aggregates. Although PET_50nm NPs influence the kinetics of aggregation and secondary structure, the overall morphology of the resulting fibrils remains largely unaltered, as seen using transmission electron microscopy. Also, the local cross-β structure of the fibrils was not affected by the presence of PET_50nm NPs during fibrillation, as confirmed using ¹³C solid-state NMR spectroscopy. Overall, these findings show that PET NPs accelerate amyloid fibril formation and alter the secondary structure of Aβ fibrils. These results also indicate that the accumulation of PET-NPs in the brain may facilitate the progression of various neurodegenerative diseases, including Alzheimer’s disease. Full article

(This article belongs to the Section Bioorganic Chemistry)

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17 pages, 5168 KiB

Open AccessArticle

Unveiling the Micro-Mechanism of Functional Group Regulation for Enhanced Dielectric Properties in Novel Natural Ester Insulating Oil TME-C₁₀

by Min Chen, Tao Zhang, Jinyuan Zhang, Chunyi Liu, Dong Chen and Jin Zhang

Molecules 2025, 30(7), 1431; https://doi.org/10.3390/molecules30071431 (registering DOI) - 24 Mar 2025

Abstract

The functional groups in the molecular structure of natural ester insulating oil have a significant impact on its physicochemical and electrical properties. This article takes the novel synthetic ester TME-C₁₀ and traditional natural ester GT molecules as research objects, and based on [...] Read more.

The functional groups in the molecular structure of natural ester insulating oil have a significant impact on its physicochemical and electrical properties. This article takes the novel synthetic ester TME-C₁₀ and traditional natural ester GT molecules as research objects, and based on density functional theory (DFT) calculations, systematically explores the micro-mechanism of the effects of C=C double bonds, ester groups (-COOC), and β-H groups on the performance of insulating oils. The results show that the chemical stability and anti-aging ability of the TME-C₁₀ molecule are significantly improved by eliminating the C=C double bond and β-H group. The electronic behavior of the TME-C₁₀ molecule is mainly controlled by the ester group (-COOC), while the GT molecule is significantly affected by the unsaturated C=C double bond, resulting in a significant difference in the mode of electronic transition between the two molecules: the TME-C₁₀ molecule shows the

n \to σ^{*}

transition, while the GT molecule is the

π \to π^{*}

transition. In addition, the HOMO orbital energy level, electron transition energy, and ionization energy of the GT molecules are lower than those of the TME-C₁₀ molecules. Under the action of an external electric field, the TME-C₁₀ molecules exhibit excellent dielectric properties. In summary, the TME-C₁₀ molecules not only overcome the aging defects of traditional natural ester insulating oils, but also possess excellent insulation properties, making it a new type of insulating oil material with broad application prospects. Full article

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15 pages, 4290 KiB

Open AccessFeature PaperArticle

Structural Rearrangement in Cyclic Cu(II) Pyridyltriazole Complexes: Oxidation of Dabco to Oxalate and CO₂ Conversion to Carbonate

by Uttam R. Pokharel, Frank R. Fronczek and Andrew W. Maverick

Molecules 2025, 30(7), 1430; https://doi.org/10.3390/molecules30071430 (registering DOI) - 24 Mar 2025

Abstract

Structural rearrangements in metal–organic supramolecules constructed from the coordination of Cu(II) with m-xpt (m-xylylenebis(pyridyltriazole)) are investigated upon their interaction with 1,4-diazabicyclo[2.2.2]octane (dabco) and carbon dioxide-enriched air. The binuclear [Cu₂(m-xpt)₂]⁴⁺ complexes react with dabco [...] Read more.

Structural rearrangements in metal–organic supramolecules constructed from the coordination of Cu(II) with m-xpt (m-xylylenebis(pyridyltriazole)) are investigated upon their interaction with 1,4-diazabicyclo[2.2.2]octane (dabco) and carbon dioxide-enriched air. The binuclear [Cu₂(m-xpt)₂]⁴⁺ complexes react with dabco to produce a carbonate-bridged trinuclear complex, [Cu₃(m-xpt)₃(µ-CO₃)]⁴⁺, and an oxalate-bridged binuclear complex, [Cu₂(m-xpt)₂(µ-C₂O₄)]²⁺, where carbonate and oxalate likely originate from CO₂ and dabco, respectively. The trinuclear complex reassembles the original dimer upon the removal of the carbonate ion and converts to an oxalate-bridged binuclear complex upon treatment with ascorbic acid followed by air oxidation. Similarly, polymeric [Cu(o-xpt)(PF₆)]_n, formed from Cu(I) and o-xpt (o-xylylenebis(pyridyltriazole)) coordination, undergoes oxidation in CO₂-enriched air to yield a tetranuclear Cu(II) complex, Cu₄(o-xpt)₃(μ₄-CO₃)(μ₂-OH)(μ₂-OCOCH₃)⁴⁺. The reaction progress is monitored by UV-Vis spectroscopy, and the major products are characterized by single-crystal X-ray diffraction. Full article

(This article belongs to the Special Issue Host–Guest Inclusion Complexes and Their Miscellaneous Applications)

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17 pages, 5260 KiB

Open AccessArticle

Peri-Substituted Acyl Pyrrolyl Naphthalenes: Synthesis, Reactions and Photophysical Properties

by Junkai Zhao, Robert Pike and Christopher Abelt

Molecules 2025, 30(7), 1429; https://doi.org/10.3390/molecules30071429 (registering DOI) - 24 Mar 2025

Abstract

The preparation of two 1-acyl-8-pyrrolylnaphthalenes (5 and 6) and one pyrrolone (8) are reported along with the issues complicating the preparations of other compounds. The photophysical behavior of the fused, planar derivative 6 is explored in detail. The fluorescence [...] Read more.

The preparation of two 1-acyl-8-pyrrolylnaphthalenes (5 and 6) and one pyrrolone (8) are reported along with the issues complicating the preparations of other compounds. The photophysical behavior of the fused, planar derivative 6 is explored in detail. The fluorescence of 6 shows solvato-chromism due to intramolecular charge transfer in the excited state and enhanced emission in protic solvents. The emission intensity increases very linearly with the H-bond-donating strength of the solvent. Preferential solvation studies, multilinear regression analysis and computational modeling suggest that the fluorescence enhancement results from inhibition of the spin–orbit coupling-promoted intersystem crossing from the π→π* singlet state to an n→π* triplet state. Some of the inhibitions are due to the dielectric stabilization of the excited singlet state. A stronger effect is obtained from H-bonding, which not only further stabilizes the singlet state but also negatively impacts the vibronic coupling between the states. Full article

(This article belongs to the Special Issue Exclusive Papers of Editorial Board Members and Invited Scholars in “Materials Chemistry”, 2nd Edition)

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1 pages, 129 KiB

Open AccessCorrection

Correction: Nawrot et al. The Anti-Serotonin Effect of Parthenolide Derivatives and Standardised Extract from the Leaves of Stizolophus balsamita. Molecules 2019, 24, 4131

by Joanna Nawrot, Marta Napierała, Kinga Kaczerowska-Pietrzak, Ewa Florek, Justyna Gornowicz-Porowska, Ewa Pelant and Gerard Nowak

Molecules 2025, 30(7), 1428; https://doi.org/10.3390/molecules30071428 (registering DOI) - 24 Mar 2025

Abstract

The authors would like to make the following correction to the published paper [...] Full article

23 pages, 7194 KiB

Open AccessArticle

Phytochemical Profile, Antioxidant Capacity and Anticancer Potential of Water Extracts from In Vitro Cultivated Salvia aethiopis

by Krasimira Tasheva, Inna Sulikovska, Ani Georgieva, Vera Djeliova, Vesela Lozanova, Anelia Vasileva, Ivaylo Ivanov, Petko Denev, Maria Lazarova, Valya Vassileva and Polina Petkova-Kirova

Molecules 2025, 30(7), 1427; https://doi.org/10.3390/molecules30071427 (registering DOI) - 23 Mar 2025

Abstract

Salvia aethiopis L. (Mediterranean sage) is a medicinal plant known for its rich phenolic content and different therapeutic properties. This study evaluated the phytochemical composition, antioxidant capacity and anticancer potential of water extracts from in vitro cultivated S. aethiopis. The extract exhibited [...] Read more.

Salvia aethiopis L. (Mediterranean sage) is a medicinal plant known for its rich phenolic content and different therapeutic properties. This study evaluated the phytochemical composition, antioxidant capacity and anticancer potential of water extracts from in vitro cultivated S. aethiopis. The extract exhibited a high total polyphenol (110.03 ± 0.7 mg GAE/g) and flavonoid (7.88 ± 0.25 mg QE/g) content, along with a strong oxygen radical absorbance capacity (an ORAC value of 3677.9 ± 24.8 µmol TE/g). LC-HRMS analysis identified 21 bioactive compounds, including salvianic acid C, rosmarinic acid, salvianolic acid K and various organic acids. A cytotoxicity evaluation using the Neutral Red Uptake assay showed that the extract had a low toxicity to non-cancerous BALB/3T3 cells. An antiproliferative activity assessment via the MTT assay revealed selective cytotoxicity against Hep G2 hepatocellular carcinoma cells (IC₅₀ = 353.8 ± 21.8 µg/mL) and lung (A549) and prostate (PC-3) carcinoma cell lines. Migration assays and cytopathological evaluations confirmed the significant inhibition of cancer cell proliferation, the suppression of migration and G2/M cell cycle arrest. Flow cytometry revealed considerable increases in apoptotic and necrotic cell populations following treatment with S. aethiopis extract. These findings showed the potential of S. aethiopis as a promising source of bioactive compounds with antioxidant and anticancer properties, supporting its further exploration for therapeutic applications. Full article

(This article belongs to the Special Issue Extraction and Analysis of New Bioactive Compounds Derived from Natural Products, 2nd Edition)

27 pages, 5585 KiB

Open AccessArticle

Lignin as a Bioactive Additive in Chlorzoxazone-Loaded Pharmaceutical Tablets

by Andreea Creteanu, Gabriela Lisa, Cornelia Vasile, Maria-Cristina Popescu, Daniela Pamfil, Alina-Diana Panainte, Gladiola Tantaru, Madalina-Alexandra Vlad and Claudiu N. Lungu

Molecules 2025, 30(7), 1426; https://doi.org/10.3390/molecules30071426 (registering DOI) - 23 Mar 2025

Viewed by 20

Abstract

In the present work, the application of lignin (LIG) as a bioactive additive for the preparation of drug-loaded tablets by direct compression has been studied, and its influence on the release of chlorzoxazone (CLZ) from the hydrophilic matrices has been followed. In hydrophilic [...] Read more.

In the present work, the application of lignin (LIG) as a bioactive additive for the preparation of drug-loaded tablets by direct compression has been studied, and its influence on the release of chlorzoxazone (CLZ) from the hydrophilic matrices has been followed. In hydrophilic matrices, the excipients Kollidon^® SR (KOL) and chitosan (CHT) have been used in various amounts and tested in the preparation of 500 mg tablets. They were used as matrix-forming agents, and their influence on the flow and the compressibility properties as well as their effect on the pharmaco-chemical characteristics of the matrix tablets have been studied. Based on the initial evaluation of the pharmaco-technical analysis, pharmaco-chemical characteristics, and in vitro release profile, three matrix tablet formulations (FLa, FLb, and FLc) were selected and further tested. They were evaluated through Fourier-transform infrared spectrometry (FTIR), X-ray diffraction (XRD), thermogravimetry (TG), differential scanning calorimetry (DSC), and in vitro dissolution tests. The three formulations were comparatively studied regarding the release kinetics of active substances using in vitro release testing. The in vitro kinetic study reveals a complex release mechanism occurring in two steps of drug release. The first one is a burst effect that occurs within the first 0–2 h, involving a rapid release of the majority of the drug in a short time, followed by the second step as a prolonged release of the drug, which is relatively constant with a fixed rate over the next 2–36 h. Two factors have been calculated to assess the release profile of chlorzoxazone: f1—the similarity factor and f2—the difference factor together with the correlation coefficient R². Comparing their values, the three optimal formulations have been selected, containing 55 mg LIG (FLa), 60 mg LIG (FLb), or 65 mg LIG (FLc), confirming that LIG next to KOL and CHT influenced the release characteristics of the matrix tablets. Due to the presence of lignin in the matrix of the three formulations, FLa, FLb, and FLc tablets with CLZ, the antioxidant activity has improved. The antioxidant activity of FLc was found to be 21.36% ± 1.06 greater than that of FLa and FLb. The tablets FLa, FLb, and FLc also presented higher antimicrobial activity against Staphylococcus aureus, Escherichia coli, Candida albicans, and colistin-resistant Klebsiella spp. The higher the concentration of LIG in the matrix (FLc), the higher the antimicrobial activity. By using LIG, the drug dose could be decreased. It can be concluded that lignin can be used as a multifunctional pharmaceutical bioactive additive/excipient for tablets. Its interesting properties have been proven, and its use as a pharmaceutical active additive should be exploited for different applications. Full article

(This article belongs to the Special Issue Research Progress and Application of Natural Compounds—2nd Edition)

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19 pages, 4135 KiB

Open AccessArticle

Macro- and Microelement Composition, Antioxidant Activity, and Biological Effect of Cold-Pressed Edible Oils from Commercial and Amateur Companies

by Jolanta Marciniuk, Beata Sadowska, Marzena Więckowska-Szakiel, Mateusz Borkowski, Jacek Zebrowski, Bronisław K. Głód, Kacper Marciniuk and Paweł Marciniuk

Molecules 2025, 30(7), 1425; https://doi.org/10.3390/molecules30071425 (registering DOI) - 23 Mar 2025

Viewed by 23

Abstract

The aim of this study was to examine cold-pressed oils available on the Polish market derived from different plants and manufacturers in the context of their biological activity, including micro- and macroelements, antioxidant properties, antimicrobial activity, and selected effects on eukaryotic cells. In [...] Read more.

The aim of this study was to examine cold-pressed oils available on the Polish market derived from different plants and manufacturers in the context of their biological activity, including micro- and macroelements, antioxidant properties, antimicrobial activity, and selected effects on eukaryotic cells. In total, 76 oil samples of 34 selected oil types from nine Polish companies (five commercial and four amateur) were tested. The content of macro- and micronutrients was assessed using ICP-OES, the level of fatty acid unsaturation was examined using Fourier transform infrared spectroscopy (FTIR), and total antioxidant potential (TAP) was assessed using the DPPH method. The antimicrobial activity of the selected oils against Gram-positive and Gram-negative bacteria, as well as fungi, representing both pathogens and human microbiota, was tested using the broth microdilution method. The MTT reduction assay was used to exclude the cytotoxic effect of the oils on the human fibroblast line HFF-1. It has been concluded that the composition of cold-pressed oils varied significantly depending on the plant used and the manufacturer. The total content of the elements tested ranged from 172.91 mg/kg in Helianthus annuus oil to 1580.73 mg/kg in Silybum marianum oil. The iron concentration limits were exceeded in 10 oils, the copper concentration limits were exceeded in 34 oils, and the lead concentration limits were exceeded in 18 oils. At least one of these elements was exceeded in 40 oils (53% of the tested samples), which is why testing the concentration of elements should be a standard procedure for assessing the quality of cold-pressed oils. There was no statistically significant correlation between the content of any macro- and microelements and TAP. While TAP was strongly correlated with the spectral unsaturation index of the oils, this relationship can be used to develop a simple and rapid assessment of oils quality. The strongest antioxidant activity (over 90%) was observed for Nigella sativa oils. Interestingly, among all the tested oils, only these from Nigella sativa L., whatever the producer, possessed also strong antimicrobial activity. None of the tested oils showed cytotoxicity against eukaryotic cells, so the cold-pressed oils can be considered safe. Full article

(This article belongs to the Section Food Chemistry)

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17 pages, 5043 KiB

Open AccessArticle

A Density Functional Theory Study on the Effects of Silver Doping on the Properties and Flotation Behavior of Jamesonite

by Huimin Chen, Xi Yang, Yuqiong Li and Jianhua Chen

Molecules 2025, 30(7), 1424; https://doi.org/10.3390/molecules30071424 (registering DOI) - 23 Mar 2025

Viewed by 35

Abstract

Silver (Ag) is a precious and valuable metal, and it has many carrier minerals. Through LA-ICP-MS analysis, it was found that jamesonite not only contains lead (Pb) and antimony (Sb) as precious metals but also trace amounts of Ag. In practice, the flotation [...] Read more.

Silver (Ag) is a precious and valuable metal, and it has many carrier minerals. Through LA-ICP-MS analysis, it was found that jamesonite not only contains lead (Pb) and antimony (Sb) as precious metals but also trace amounts of Ag. In practice, the flotation method is generally used to recover these metals. This paper employs density functional theory calculations to demonstrate that after Ag doping in jamesonite, the Ag atoms exist in the lattice channels of jamesonite, and they form strong covalent bonds with the S atoms, resulting in strong interactions. When Ag is doped in the channels, the adsorption of sodium diethyldithiocarbamate (DDTC) as a collector on the Ag-doped jamesonite surface is the strongest, while that of butyl xanthate is the weakest. The adsorption interactions on the Ag-doped jamesonite surface are also stronger than on pure jamesonite. Coordination chemistry studies reveal that Ag⁺ undergoes a transition from a d¹⁰ to a d⁹s¹ electronic configuration when incorporated into jamesonite, which increases its reactivity by generating unpaired electrons available for π-backbonding with collector molecules. Furthermore, owing to the high polarizability of Ag, the presence of Ag atoms alters the electronic environment of the surrounding Pb atoms, which enhances the π-backbonding interactions between the adsorbate reagent molecules and the Ag active sites. The research results are of great significance for the efficient recovery of Ag-containing jamesonite and provide a reference for the study of the properties of Ag-doped minerals. Full article

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26 pages, 5132 KiB

Open AccessArticle

Phenolics as Active Ingredients in Skincare Products: A Myth or Reality?

by Ana Jesus, Smeera Ratanji, Honorina Cidade, Emília Sousa, Maria T. Cruz, Rita Oliveira and Isabel F. Almeida

Molecules 2025, 30(7), 1423; https://doi.org/10.3390/molecules30071423 (registering DOI) - 23 Mar 2025

Viewed by 33

Abstract

Phenolic compounds, with their diverse biological activities, are widely explored as cosmetic ingredients with photoprotective, antioxidant, anti-inflammatory, and anti-hyperpigmentation properties, offering a multitargeted approach to combat photo-induced skin aging. The study analyzed 1299 cosmetic products from 2021 to 2024 to understand the market [...] Read more.

Phenolic compounds, with their diverse biological activities, are widely explored as cosmetic ingredients with photoprotective, antioxidant, anti-inflammatory, and anti-hyperpigmentation properties, offering a multitargeted approach to combat photo-induced skin aging. The study analyzed 1299 cosmetic products from 2021 to 2024 to understand the market impact of phenolic compounds and their mechanism of action against photo-induced skin damage. A total of 28 active phenolic compounds were identified and the prevalence of phenolics was 13.2% in anti-aging products, 5.2% in sunscreens and 4.8% in aftersun products. Bakuchiol and polyphenols, such as resveratrol, chrysin, and hesperidin methyl chalcone, were found in anti-aging products. Sunscreens and aftersun products were counted with ferulic and caffeic acids, and salicylic acid, respectively. Antioxidant activity was found to be the primary mechanism of action of phenolic compounds by scavenging reactive species, thus mitigating oxidative stress. Ferulic and caffeic acids, chrysin, and glucosylrutin can also absorb UV radiation, acting preventively against solar-induced skin damage. This study provides insights into the limited use of phenolic compounds in commercial cosmetics, despite their diverse biological activities, and suggests potential barriers to wider use in skin and sun care products. Full article

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

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13 pages, 1908 KiB

Open AccessArticle

Aggregation-Induced Luminescent 3-Phenylpyrano[4,3-b]quinolizine Derivatives as Photosensitizers with Anti-Cancer Properties

by Masayori Hagimori, Tatsusada Yoshida, Takuma Tsutsumi, Fumiko Hara, Shinya Takada, Yukiko Ogawa and Keitaro Tanaka

Molecules 2025, 30(7), 1422; https://doi.org/10.3390/molecules30071422 (registering DOI) - 23 Mar 2025

Viewed by 39

Abstract

Photodynamic therapy (PDT) has garnered significant attention as an effective and safe method for cancer therapy, with ongoing efforts to develop new photosensitizers to enhance its efficacy. This study aimed to develop novel photosensitizers with aggregation-induced emission enhancement (AIEE) properties. A series of [...] Read more.

Photodynamic therapy (PDT) has garnered significant attention as an effective and safe method for cancer therapy, with ongoing efforts to develop new photosensitizers to enhance its efficacy. This study aimed to develop novel photosensitizers with aggregation-induced emission enhancement (AIEE) properties. A series of 3-phenyl pyrano[4,3-b]quinolizine compounds (3–10) were synthesized by reacting pyrones (1a–e) with 2-pyridylacetate (2a) or 2-pyridylacetonitrile (2b) and then evaluated for their potential as photosensitizers. Spectroscopic analyses revealed that all compounds emitted blue to green fluorescence in ethanol, with emission wavelengths ranging from 446 nm to 515 nm. Compounds 5 and 6, lacking a substituent at position 5 of pyrano[4,3-b]quinolizine, exhibited AIEE behavior in aqueous solution. Furthermore, all compounds produced reactive oxygen species upon exposure to LED light. Notably, compounds 5 and 6 demonstrate high singlet oxygen (¹O₂) generation efficiency in water-rich solvents, where they tend to aggregate, contributing to their potential to destroy cancer cells. In vitro studies using human colon cancer cells (Colo205) demonstrated that 5 and 6 exhibited potent anti-tumor activity upon exposure to LED light. These findings suggest that compounds 5 and 6, based on 3-phenyl pyrano[4,3-b]quinolizine, possessing AIEE properties, are potential new photosensitizers for PDT. Full article

(This article belongs to the Special Issue Design, Synthesis and Evaluation of Novel Anticancer Agents, 2nd Edition)

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33 pages, 1722 KiB

Open AccessArticle

Novel Isatin–Chalcone Hybrid Molecules: Design, Synthesis and Anti-Neuroinflammatory Activity Evaluation

by Rongrong Wang, Zhili Zhang, Wei Jiang, Junyi Liu, Chao Tian and Meng Wang

Molecules 2025, 30(7), 1421; https://doi.org/10.3390/molecules30071421 (registering DOI) - 22 Mar 2025

Viewed by 108

Abstract

Neuroinflammation is considered a significant factor in triggering numerous neurodegenerative diseases. Hence, the development of effective anti-inflammatory drugs is of utmost urgency. In this study, three series of new isatin–chalcone hybrid derivatives were successfully designed and synthesized, and their anti-neuritis activities were explored [...] Read more.

Neuroinflammation is considered a significant factor in triggering numerous neurodegenerative diseases. Hence, the development of effective anti-inflammatory drugs is of utmost urgency. In this study, three series of new isatin–chalcone hybrid derivatives were successfully designed and synthesized, and their anti-neuritis activities were explored using BV2 microglial cells. The results indicated that compound 4b exhibited the most potent anti-inflammatory activity (IC₅₀ = 1.6 μM; TI = 21.6). After being treated with compound 4b, the production of TNF-α and IL-6 decreased significantly (p < 0.0001). In silico molecular modeling studies on inflammation proteins suggested that compound 4b might bind to TLR4/MD2 and p38. Predicted by the software Molinspiration, the Log p value and Log BB of compound 4b were 3.36 and −0.32, respectively. Full article

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15 pages, 3617 KiB

Open AccessArticle

The Molecular Recognition of Lurasidone by Human Serum Albumin: A Combined Experimental and Computational Approach

by Nevena Živković, Emina Mrkalić, Ratomir Jelić, Jovica Tomović, Jadranka Odović, Marina Ćendić Serafinović and Miroslav Sovrlić

Molecules 2025, 30(7), 1420; https://doi.org/10.3390/molecules30071420 (registering DOI) - 22 Mar 2025

Viewed by 124

Abstract

Lurasidone (LUR) is an antipsychotic drug whose interaction with human serum albumin (HSA) plays a crucial role in its pharmacokinetic and pharmacodynamic properties. A thorough understanding of LUR’s binding mechanism to HSA is crucial for predicting its transport, distribution, and potential drug interactions. [...] Read more.

Lurasidone (LUR) is an antipsychotic drug whose interaction with human serum albumin (HSA) plays a crucial role in its pharmacokinetic and pharmacodynamic properties. A thorough understanding of LUR’s binding mechanism to HSA is crucial for predicting its transport, distribution, and potential drug interactions. Methods: The interaction between LUR and HSA was investigated using fluorescence and circular dichroism (CD) spectroscopy, followed by molecular docking simulations. Binding characteristics were analyzed through quenching mechanisms, thermodynamic parameters, and competitive site marker experiments. Results: This study revealed a systematic decrease in HSA fluorescence intensity with increasing LUR concentration, indicating a static quenching mechanism driven by non-fluorescent complex formation. Binding constants suggest enhanced complex stability at higher temperatures, with thermodynamic analysis confirming an endothermic, hydrophobic interaction. Competitive site marker assays and synchronous fluorescence spectra confirmed that LUR primarily binds to site I (subdomain IIA) near tryptophan residues. Conformational changes in HSA, observed as a decrease in α-helix content, further demonstrate the structural impact of LUR binding. Conclusions: These findings offer key insights into the molecular interactions between LUR and HSA, enhancing our understanding of LUR’s pharmacokinetics and its potential interactions with other drugs. Understanding these binding characteristics can aid in optimizing LUR’s clinical application and predicting possible interactions with other biomolecules. Full article

(This article belongs to the Special Issue Exploring Analytical Techniques in Pharmaceutical and Biomedical Analysis)

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25 pages, 7588 KiB

Open AccessArticle

Antiviral Activity of Halogenated Compounds Derived from L-Tyrosine Against SARS-CoV-2

by Paula A. Velásquez-Bedoya, María I. Zapata-Cardona, Laura M. Monsalve-Escudero, Jaime A. Pereañez, Diego Guerra-Arias, Manuel Pastrana-Restrepo, Elkin Galeano and Wildeman Zapata-Builes

Molecules 2025, 30(7), 1419; https://doi.org/10.3390/molecules30071419 (registering DOI) - 22 Mar 2025

Viewed by 177

Abstract

Introduction: Currently, there are no effective medications for treating all the clinical conditions of patients with COVID-19. We aimed to evaluate the antiviral activity of compounds derived from L-tyrosine against the B.1 lineage of SARS-CoV-2 in vitro and in silico. Methodology: The cytotoxicities [...] Read more.

Introduction: Currently, there are no effective medications for treating all the clinical conditions of patients with COVID-19. We aimed to evaluate the antiviral activity of compounds derived from L-tyrosine against the B.1 lineage of SARS-CoV-2 in vitro and in silico. Methodology: The cytotoxicities of 15 halogenated compounds derived from L-tyrosine were evaluated in Vero-E6 cells by the MTT assay. The antiviral activity of the compounds was evaluated using four strategies, and viral quantification was performed by a plaque assay and qRT-PCR. The toxicity of the compounds was evaluated by ADMET predictor software. The affinity of these compounds for viral or cellular proteins and the stability of their conformations were determined by docking and molecular dynamics, respectively. Results: TODC-3M, TODI-2M, and YODC-3M reduced the viral titer >40% and inhibited the replication of viral RNA without significant cytotoxicity. In silico analyses revealed that these compounds presented low toxicity and binding energies between −4.3 and −5.2 Kcal/mol for three viral proteins (spike, Mpro, and RdRp). TODC-3M and YODC-3M presented the most stable conformations with the evaluated proteins. Conclusions: The most promising compounds were TODC-3M, TODI-2M, and YODC-3M, which presented low in vitro and in silico toxicity, antiviral potential through different strategies, and favorable affinities for viral targets. Therefore, they are candidates for in vivo studies. Full article

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25 pages, 3715 KiB

Open AccessArticle

Alkaloid Extraction from Coptis chinensis Franch. Using Ultrasound-Assisted Aqueous Solutions of Surfactants, Organic Acids, Deep Eutectic Solvents, and Supramolecular Deep Eutectic Solvents

by Khan Viet Nguyen, Nhan Trong Le, Vy Thao Thi Dang, Oleh Koshovyi, Ain Raal and Hoai Thi Nguyen

Molecules 2025, 30(7), 1418; https://doi.org/10.3390/molecules30071418 (registering DOI) - 22 Mar 2025

Viewed by 108

Abstract

Berberine, palmatine, and coptisine are bioactive alkaloids commonly found in medicinal plants, including Coptis chinensis Franch. (Ranunculaceae). To address the limitations of conventional volatile organic solvents, this study employed eco-friendly solvents—aqueous solutions of surfactants, carboxylic acids, and deep eutectic solvents—to extract these alkaloids. [...] Read more.

Berberine, palmatine, and coptisine are bioactive alkaloids commonly found in medicinal plants, including Coptis chinensis Franch. (Ranunculaceae). To address the limitations of conventional volatile organic solvents, this study employed eco-friendly solvents—aqueous solutions of surfactants, carboxylic acids, and deep eutectic solvents—to extract these alkaloids. Among the solvents tested, lactic acid, malic acid, and pyruvic acid exhibited the highest extraction efficiencies. Optimal extraction conditions for ultrasound-assisted extraction were determined via response surface methodology. For lactic acid, optimal conditions included a concentration of 96% (w/w), a liquid-to-solid ratio of 30.0 mL/g, and a temperature of 60.0 °C, yielding 139.6 ± 0.2 mg/g of total alkaloids. Malic acid at 40.0% (w/w), 30.0 mL/g, and 80.0 °C produced 133.0 ± 0.5 mg/g, while pyruvic acid at 88.0% (w/w), 30.0 mL/g, and 75.0 °C resulted in 146.3 ± 0.4 mg/g. The recovery efficiencies of these alkaloids were further enhanced using macroporous resins. The XAD-8 and AB-8 resins achieved recovery rates of 80.11 ± 0.78% and 79.00 ± 1.06%, respectively, for lactic acid extracts. The LSA-40 resin yielded efficiencies of 95.58 ± 1.40% and 89.86 ± 0.90% for malic and pyruvic acid extracts, respectively. Notably, the combination of malic acid as an extraction solvent and the HPD-400 resin achieved an impressive alkaloid recovery yield of 79.52% from C. chinensis. This work represents the first reported application of this approach and highlights the potential of green solvents and macroporous resins for sustainable and efficient alkaloid extraction from C. chinensis. Full article

(This article belongs to the Special Issue Extraction, Identification and Isolation of Chemical Compounds in Natural Matrices, 2nd Edition)

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17 pages, 5569 KiB

Open AccessArticle

Ag₂S/Zn²⁺-Decorated g-C₃N₄ Type-II Heterojunction with Wide-Spectrum Response: Construction and Photocatalytic Performance in Ciprofloxacin Degradation

by Chengyang Wang, Han Zheng, Ruxue Ma, Xiucheng Zheng and Xinxin Guan

Molecules 2025, 30(7), 1417; https://doi.org/10.3390/molecules30071417 (registering DOI) - 22 Mar 2025

Viewed by 123

Abstract

Antibiotic-based wastewaters seriously endanger human health and damage the ecological environment, and photocatalytic degradation is a desirable strategy for eliminating these contaminants in water. Therefore, developing a proper catalyst for the photodegradation of antibiotics, including ciprofloxacin (CIP), is of great importance. In this [...] Read more.

Antibiotic-based wastewaters seriously endanger human health and damage the ecological environment, and photocatalytic degradation is a desirable strategy for eliminating these contaminants in water. Therefore, developing a proper catalyst for the photodegradation of antibiotics, including ciprofloxacin (CIP), is of great importance. In this study, novel Ag₂S/Zn²⁺-decorated graphitic carbon nitride (AZCN for short) type-II heterojunctions are constructed through a precipitation–calcination procedure. The high porosity with a specific surface area of 133.5 m² g⁻¹, as well as the positive synergy between Ag₂S- and Zn²⁺-decorated graphitic carbon nitride (abbreviated as ZCN), enhance incident light harvesting, increase the adsorption capacity for reactant molecules, favor mass transfer and promote the separation and transport of photoinduced carriers, therefore improving the degradation efficiency of CIP. Specifically, the degradation efficiency of CIP (50 mL, 10 mg L⁻¹) over 2.5% AZCN (10 mg) is 18.1%, 43.1% and 55.7% within 60 min of irradiation using near-infrared light, visible light and simulated solar light, respectively. Moreover, it displays satisfactory recycling stability and excellent universality. This research not only develops a promising heterojunction photocatalyst but also offers some valuable insights in water remediation. Full article

(This article belongs to the Special Issue Inorganic/Organic Catalysts: Moving towards an Efficient, Green, and Sustainable Future)

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26 pages, 4819 KiB

Open AccessFeature PaperArticle

Thermodynamic and Kinetic Characterization of Colloidal Polymers of N-Isopropylacrylamide and Alkyl Acrylic Acids for Optical pH Sensing

by James T. Moulton, David Bruce, Richard A. Bunce, Mariya Kim, Leah Oxenford Snyder, W. Rudolf Seitz and Barry K. Lavine

Molecules 2025, 30(7), 1416; https://doi.org/10.3390/molecules30071416 (registering DOI) - 22 Mar 2025

Viewed by 121

Abstract

Copolymers of N-isopropylacrylamide (NIPA) and alkyl acrylic acids that swell and shrink in response to pH were prepared by dispersion polymerization at 35 °C using N-isopropylacrylamide (transduction monomer), methylenebisacrylamide (crosslinker), 2-dimethoxy-2-phenyl-acetophenone (initiator), N-tert-butylacrylamide (transition temperature modifier), and acrylic [...] Read more.

Copolymers of N-isopropylacrylamide (NIPA) and alkyl acrylic acids that swell and shrink in response to pH were prepared by dispersion polymerization at 35 °C using N-isopropylacrylamide (transduction monomer), methylenebisacrylamide (crosslinker), 2-dimethoxy-2-phenyl-acetophenone (initiator), N-tert-butylacrylamide (transition temperature modifier), and acrylic acid, methacrylic acid, ethacrylic acid, and propacrylic acid (functional comonomer). The diameter of the microspheres of the copolymer varied between 0.5 µm and 1.0 µm. These microspheres were cast into hydrogel membranes prepared by mixing the pH-sensitive swellable polymer particles with aqueous polyvinyl alcohol solutions followed by crosslinking the polyvinyl alcohol with glutaric dialdehyde for use as pH sensors. Large changes in the turbidity of the polyvinyl alcohol membrane monitored using a Cary 6000 UV–visible absorbance spectrometer were observed as the pH of the buffer solution in contact with the membrane was varied. Polymer swelling was reversible for many of these NIPA-based copolymers. The buffer capacity, ionic strength, pH, and temperature of the buffer solution in contact with the membrane were systematically varied to provide an in-depth pH profile of each copolymer. A unique aspect of this study was the investigation of the response of the NIPA-based polymers to changes in the pH of the solution in contact with the membrane at low buffer concentrations (0.5 mM). The response rate and the reversibility of polymer swelling even at low buffer capacity suggest that NIPA-based copolymers can be coupled to an optical fiber for pH sensing in the environment. We envision using these polymers to monitor rising acidity levels in the ocean due to water that has become enriched in carbon dioxide that endangers shell-building organisms by reducing the amount of carbonate available to them. Full article

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17 pages, 2851 KiB

Open AccessArticle

Synthesis of Imidazolidin-2-ones from trans-(R,R)-Diaminocyclohexane: A Statistical Analysis-Based Pseudo-Multicomponent Protocol

by Catalina Hoyos-Orozco, Lili Dahiana Becerra and Diego Quiroga

Molecules 2025, 30(7), 1415; https://doi.org/10.3390/molecules30071415 (registering DOI) - 22 Mar 2025

Viewed by 126

Abstract

A pseudo-multicomponent one-pot protocol for the synthesis of 1,3-disubstituted imidazolidin-2-one is described, employing trans-(R,R)-diaminocyclohexane for the in situ formation of the Schiff base, followed by reduction to produce the respective diamine and cyclization with carbonyldiimidazole (CDI). This approach [...] Read more.

A pseudo-multicomponent one-pot protocol for the synthesis of 1,3-disubstituted imidazolidin-2-one is described, employing trans-(R,R)-diaminocyclohexane for the in situ formation of the Schiff base, followed by reduction to produce the respective diamine and cyclization with carbonyldiimidazole (CDI). This approach utilizes statistical analysis to optimize the reaction conditions, allowing a pseudo-multicomponent protocol to be proposed. The developed method demonstrates sustainability, efficiency, and potential applications in green chemistry, achieving yields ranging from 55% to 81%. This represents a significant advance in synthesizing heterocyclic compounds with biological and pharmacological applications. Full article

(This article belongs to the Section Organic Chemistry)

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10 pages, 2814 KiB

Open AccessFeature PaperArticle

Indocyanine Green-Loaded Quenched Nanoliposomes as Activatable Theranostics for Cancer

by Junwoo Lim, Yeojin Yoo and Yongdoo Choi

Molecules 2025, 30(7), 1414; https://doi.org/10.3390/molecules30071414 (registering DOI) - 22 Mar 2025

Viewed by 107

Abstract

Photodynamic therapy (PDT) and photothermal therapy (PTT) are considered to be one of the most effective methods for treating cancer due to their noninvasive nature, high effectiveness, and fewer side effects compared to standard therapeutic modalities for cancer. However, conventional always-on types of [...] Read more.

Photodynamic therapy (PDT) and photothermal therapy (PTT) are considered to be one of the most effective methods for treating cancer due to their noninvasive nature, high effectiveness, and fewer side effects compared to standard therapeutic modalities for cancer. However, conventional always-on types of PDT and PTT agents have basic drawbacks in their in vivo applications, which include the unwanted generation of strong fluorescence signals and phototoxicity in normal tissues, including blood vessels, when exposed to light, resulting in poor imaging contrast and unwanted phototoxicity. Here, we propose indocyanine green-loaded quenched nanoliposomes (Q-ICG-NLs) as an activatable nanotheranostics. Q-ICG-NLs showed significant quenching in near-infrared fluorescence emission and singlet oxygen generation upon light irradiation. The photothermal effect of Q-ICG-NLs was 1.3 times greater than free indocyanine green. Its fluorescence and singlet oxygen generation were largely restored when taken up into cancer cells, enabling the selective detection and phototherapy of cancer cells. These results suggest that Q-ICG-NLs can be effectively used for selective near-infrared fluorescence imaging and the subsequent image-guided PDT and PTT of cancers. Full article

(This article belongs to the Section Applied Chemistry)

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13 pages, 2793 KiB

Open AccessArticle

Composite ZIF-8 with Cs₃Bi₂I₉ to Enhance the Photodegradation Ability on Methylene Blue

by Tao Tang, Haoran Zhang, Hexu Wang, Xiaoyu Dou, Jianfeng Wen and Li Jiang

Molecules 2025, 30(7), 1413; https://doi.org/10.3390/molecules30071413 (registering DOI) - 22 Mar 2025

Viewed by 127

Abstract

The development of green, efficient, and reusable photocatalysts is important for pollution degradation. In recent years, Cs₃Bi₂I₉ has been shown to be an effective photocatalyst. However, the rapid recombination of electrons and holes weakens the photocatalytic activity. In [...] Read more.

The development of green, efficient, and reusable photocatalysts is important for pollution degradation. In recent years, Cs₃Bi₂I₉ has been shown to be an effective photocatalyst. However, the rapid recombination of electrons and holes weakens the photocatalytic activity. In this work, the photogenerated electron transfer rate was promoted by ZIF-8 compositing with Cs₃Bi₂I₉, which effectively improved the pollutant degradation. After 50 min of visible light irradiation, Cs₃Bi₂I₉/ZIF-8 removed up to 98.2% of methylene blue (MB), which was 4.15 times higher than that of Cs₃Bi₂I₉ alone. In addition, the Cs₃Bi₂I₉/ZIF-8 composite still exhibited high photocatalytic activity after three cycling experiments. Our research offers a simple and efficient method for enhancing the photocatalytic activity of lead-free halide perovskites. Full article

(This article belongs to the Special Issue Photocatalysis for Energy Transformation Reactions and Wastewater Treatment)

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15 pages, 8484 KiB

Open AccessArticle

The Dynamical Asymmetry in SARS-CoV2 Protease Reveals the Exchange Between Catalytic Activity and Stability in Homodimers

by Velia Minicozzi, Alessandro Giuliani, Giampiero Mei, Leonardo Domenichelli, Mauro Parise, Almerinda Di Venere and Luisa Di Paola

Molecules 2025, 30(7), 1412; https://doi.org/10.3390/molecules30071412 (registering DOI) - 22 Mar 2025

Viewed by 159

Abstract

The molecular approach to understanding the mechanisms of emerging diseases, like COVID-19, has largely accelerated the search for successful therapeutical strategies. In this work, we present an extensive molecular dynamics (MD) analysis of two forms of the SARS-CoV-2 main protease M^Pro. [...] Read more.

The molecular approach to understanding the mechanisms of emerging diseases, like COVID-19, has largely accelerated the search for successful therapeutical strategies. In this work, we present an extensive molecular dynamics (MD) analysis of two forms of the SARS-CoV-2 main protease M^Pro. We analyzed the free form (apo) and compared the results with those coming from the (holo) form bound to the inhibitor Boceprevir, an FDA-approved drug repurposed for COVID-19 therapy. We applied Dynamic Cross Correlation (DCC) analysis to the MD simulations to trace the concerted motion patterns within the protein structure. Although symmetric, the homodimer in the bound form showed clearly asymmetric dynamical behavior. In particular, the presence of concerted motions was detected in the protomer where the expulsion of the substrate from the active site happened. Such behavior was not observed in the same time lapses in the apo form. These results highlight a sort of ‘symmetry breaking’, making a symmetric structure to display functional induced asymmetric behavior in response to a perturbation. This highly coordinated dynamics in response to an external cue confirms the character of ‘complex molecular machines’ of biopolymers. Full article

(This article belongs to the Special Issue Application of Computational Studies for Elucidation of Protein Structure and Function)

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20 pages, 316 KiB

Open AccessReview

Androgen Receptors in Human Breast Cancer and Female Canine Mammary Tumors

by Vladimir Vidović, Ivana Davidov, Zoran Ružić, Mihajlo Erdeljan, Annamaria Galfi Vukomanović and Bojana Blagojević

Molecules 2025, 30(7), 1411; https://doi.org/10.3390/molecules30071411 (registering DOI) - 22 Mar 2025

Viewed by 178

Abstract

This review explores the potential role of androgens in human breast cancer and female canine mammary tumors. Human breast cancer is one of the most common cancers affecting women globally, while female canine mammary tumors provide a natural model for the study of [...] Read more.

This review explores the potential role of androgens in human breast cancer and female canine mammary tumors. Human breast cancer is one of the most common cancers affecting women globally, while female canine mammary tumors provide a natural model for the study of human breast cancer due to their similar histopathologies and molecular features. Androgen receptors, typically linked to male sex hormones, are present in up to 90% of human breast tumors. These receptors interact with estrogen-receptor signaling, suggesting their involvement in a complex mechanism in cancer progression. Androgen receptors have become key players in breast cancer biology, offering new targets for therapeutic strategies. The presence of these receptors in both human and canine tumors raises important questions about their role in the development of these malignancies. While the exact mechanisms remain to be fully elucidated, research suggests that targeting androgen-receptor signaling could be a novel therapeutic approach for both humans and canines. Further studies are necessary to fully understand the implications of androgen-receptor expression and to develop more effective targeted therapies for these cancers. Full article

15 pages, 1067 KiB

Open AccessArticle

Hydrogen Bonding of Trialkyl-Substituted Urea in Organic Environment

by Zuzana Morávková, Jiří Podešva, Valeriia Shabikova, Sabina Abbrent and Miroslava Dušková-Smrčková

Molecules 2025, 30(7), 1410; https://doi.org/10.3390/molecules30071410 (registering DOI) - 21 Mar 2025

Viewed by 69

Abstract

Urea groups appear in many biomolecules and polymers. They have a significant impact on the properties of the materials because of their inherent strength and for their ability to participate in hydrogen bonds. Typically, in classical urea-based polymer materials, the urea groups occur [...] Read more.

Urea groups appear in many biomolecules and polymers. They have a significant impact on the properties of the materials because of their inherent strength and for their ability to participate in hydrogen bonds. Typically, in classical urea-based polymer materials, the urea groups occur in their N,N′-disubstituted state. Recently, bis-aspartates have been introduced as a novel type of hindered amine resins providing, upon crosslinking with (poly)isocyanates, the polyurea–polyaspartate thermosets (PU-ASPE) for coatings, sealants, polyelectrolytes, and other applications. These materials contain N,N′N′-trisubstituted urea linkages in their structures. However, the infrared (IR) characterization of trisubstituted urea groups has not been documented in sufficient detail. Consequently, studies on the structure of aspartate-based polyurea materials often rely on data from N,N′-disubstituted ureas, which can lead to inaccurate conclusions. This study presents a detailed evaluation of the possible urea H-bonding states, focusing on the difference between the di- and trisubstituted species. Particularly, the attributions of the IR spectra to urea-based hydrogen bonding states are presented both in neat materials and their solutions. To systematize this study, we initially focus on a simple trisubstituted urea model system, tributyl urea (3BUA), and compare its spectral response with disubstituted N-butyl-N′-cyclohexyl urea (1B1CHUA) and trisubstituted N-butyl-N′,N′-dicyclohexyl urea (1B2CHUA), to elucidate their hydrogen-bonding fingerprints. This research provides a thorough understanding of the IR response of the di- and trisubstituted urea species and their structural characteristics in urea-containing materials. Full article

(This article belongs to the Special Issue Exclusive Feature Papers in Physical Chemistry, 3nd Edition)

14 pages, 2673 KiB

Open AccessArticle

Construction of Hierarchical 2D-3D@3D Zn₃In₂S₆@CdS Photocatalyst for Boosting Degradation of an Azo Dye

by Andreas Katsamitros, Nikolaos Karamoschos, Labrini Sygellou, Konstantinos S. Andrikopoulos and Dimitrios Tasis

Molecules 2025, 30(7), 1409; https://doi.org/10.3390/molecules30071409 (registering DOI) - 21 Mar 2025

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Abstract

Herein, flower-like Zn₃In₂S₆ (ZIS₃) crystallites were grown onto acorn leaf-like CdS assemblies via a two-step hydrothermal approach. Under visible light irradiation, the Zn₃In₂S₆-enriched heterostructures demonstrated an enhanced azo-dye degradation rate, [...] Read more.

Herein, flower-like Zn₃In₂S₆ (ZIS₃) crystallites were grown onto acorn leaf-like CdS assemblies via a two-step hydrothermal approach. Under visible light irradiation, the Zn₃In₂S₆-enriched heterostructures demonstrated an enhanced azo-dye degradation rate, with the majority of the organic analyte (Orange G) being degraded within 60 min. In contrast, the CdS-enriched hybrids showed poor photocatalytic performance. The optimized hybrid containing a nominal CdS content of 4 wt% was characterized by various physicochemical techniques, such as XRD, SEM, XPS and Raman. XPS analysis showed that the electron density around the Zn and In sites in Zn₃In₂S₆ was slightly increased, implying a certain charge migration pattern. Complementary information from scavenging experiments suggested that hydroxy radicals were not the exclusive transient responsible for oxidative degradation of the organic azo-dye. This research provides new information about the development of metal chalcogenide-based heterostructures for efficient photocatalytic organic pollutant degradation. Full article

(This article belongs to the Special Issue Photocatalytic Materials and Photocatalytic Reactions, 2nd Edition)

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17 pages, 989 KiB

Open AccessArticle

The Role of Chalcogen in the ROS Scavenging Mechanism of Model Phenyl Compounds

by Davide Zeppilli, Veronica Pedergnana, Matteo Filippi and Laura Orian

Molecules 2025, 30(7), 1408; https://doi.org/10.3390/molecules30071408 (registering DOI) - 21 Mar 2025

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Abstract

Phenolic compounds are important antioxidants with great ROS scavenging potential and the presence of the hydroxyl groups is fundamental for this chemical activity. Therefore, changing the chalcogen atom (oxygen) with any of its siblings of group 16 (sulfur, selenium and tellurium) may affect [...] Read more.

Phenolic compounds are important antioxidants with great ROS scavenging potential and the presence of the hydroxyl groups is fundamental for this chemical activity. Therefore, changing the chalcogen atom (oxygen) with any of its siblings of group 16 (sulfur, selenium and tellurium) may affect the reactivity of these compounds. In this work, the ROS scavenging activity and mechanism of phenyl chalcogenols was evaluated in silico, unravelling better performance with heavier chalcogens, both thermodynamically and kinetically. Furthermore, a scavenging mechanism switch is reported, moving from Hydrogen Atom Transfer (HAT) in phenols to Concerted Proton Electron Transfer (CPET) in the other phenyl chalcogenols. Both kinetic trends and mechanistic features are rationalized in the framework of Activation Strain Analysis (ASA). Lastly, the role of aromaticity is evidenced by analyzing the differences between the phenol/phenoxyl and methanol/methoxyl self-exchange reactions, as well as between the corresponding processes with the other chalcogens. Full article

(This article belongs to the Special Issue Organoselenium Compounds: Synthesis, Catalysis and Biological Activities)

16 pages, 2044 KiB

Open AccessArticle

A Targeted Mass Spectrometric Approach to Evaluate the Anti-Inflammatory Activity of the Major Metabolites of Foeniculum vulgare Mill. Waste in Human Bronchial Epithelium

by Maria Assunta Crescenzi, Hector Gallart-Ayala, Cristiana Stellato, Ada Popolo, Julijana Ivanisevic, Sonia Piacente and Paola Montoro

Molecules 2025, 30(7), 1407; https://doi.org/10.3390/molecules30071407 (registering DOI) - 21 Mar 2025

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Abstract

Fennel waste is rich in compounds that may have beneficial effects on human health. For this reason, the most abundant metabolites in fennel were isolated as the following: quercetin-3-O-glucoside, quinic acid, 1,5-dicaffeoylquinic acid, kaempferol-3-O-glucuronide, and quercetin-3-O-glucuronide. After [...] Read more.

Fennel waste is rich in compounds that may have beneficial effects on human health. For this reason, the most abundant metabolites in fennel were isolated as the following: quercetin-3-O-glucoside, quinic acid, 1,5-dicaffeoylquinic acid, kaempferol-3-O-glucuronide, and quercetin-3-O-glucuronide. After inducing inflammation in human bronchial epithelial cells by stimulating them with IL-1β, the cells were treated with the specialized Foeniculum vulgare metabolites at different concentrations to assess their anti-inflammatory effect. Eicosanoids, fatty acids, and sphingolipids were extracted from the cell medium and quantified by UPLC-ESI-QTRAP-MS/MS analysis. The anti-inflammatory activity of the metabolites isolated from fennel waste was demonstrated. They were able to alleviate the inflammatory state in human bronchial epithelium by modulating the metabolic expression of both pro- and anti-inflammatory eicosanoids, fatty acids, and sphingolipids. These findings suggest the potential use of fennel waste in the production of dietary supplements to alleviate the symptoms of chronic inflammatory diseases like asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF), where the continuous use of antiphlogistics may have significant side effects. Full article

(This article belongs to the Special Issue Bioorganic Chemistry in Europe)

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17 pages, 2952 KiB

Open AccessArticle

Remediation of Hg-Contaminated Groundwater via Adsorption on Supramolecular Polymers in Batch Process and Column Test

by Zongwu Wang, Wei Liu, Xiaoyan Sun, Qing Zhang, Jiapu Ji, Yimeng Yan and Jianhui Sun

Molecules 2025, 30(7), 1406; https://doi.org/10.3390/molecules30071406 (registering DOI) - 21 Mar 2025

Viewed by 113

Abstract

Mercury contamination in groundwater seriously affects human health and ecosystem security. The remediation of Hg-contaminated groundwater remains a challenging task. The applicability of an as-synthesized supramolecular polymer (SP) for low-concentration mercury in a high-salinity groundwater matrix has been verified through a batch process [...] Read more.

Mercury contamination in groundwater seriously affects human health and ecosystem security. The remediation of Hg-contaminated groundwater remains a challenging task. The applicability of an as-synthesized supramolecular polymer (SP) for low-concentration mercury in a high-salinity groundwater matrix has been verified through a batch process and column test. The remediation of mercury-contaminated groundwater, particularly in complex high-salinity environments, represents a significant and enduring challenge in environmental science. The batch test study demonstrated that the SP can efficiently adsorb Hg from groundwater with superior selectivity and a high uptake capacity (up to 926.1 ± 165.3 mg g⁻¹). Increasing the pH and dissolved organic matter (DOM) and reducing the ionic strength can facilitate Hg adsorption; the coexistence of heavy metal ions slightly weakens the removal. In terms of its performance as a permeable reactive barrier, the SP can intercept Hg in flowing groundwater with a capacity of up to 3187 mg g⁻¹. A low influent mercury concentration, low pore velocity, and high SP dosage can effectively extend the breakthrough time in column tests. Additionally, the Yan model (R² = 0.960−0.989) can accurately depict the whole dynamic interception process (150 PVs) of SPs in a fixed column, and the Adams–Bohart model (R² = 0.916−0.964) describes the initial stage (≤35 PVs) well. Considering the functional group in the SP and the Hg species in groundwater, complexation, electrostatic attraction, ion exchange, and precipitation/co-precipitation are the plausible mechanisms for mercury removal based on the characterization results of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometer (FT-IR). These impressive features render the SP a promising candidate for the remediation of trace Hg in saline groundwater using permeable reactive barrier (PRB) technology. Full article

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3 pages, 141 KiB

Open AccessEditorial

Advanced Materials for Energy Applications: From Fuels to Batteries and Beyond

by Zhao Ding, Liangjuan Gao and Shicong Yang

Molecules 2025, 30(7), 1405; https://doi.org/10.3390/molecules30071405 - 21 Mar 2025

Viewed by 72

Abstract

The unprecedented challenges of the 21st century energy landscape necessitate a paradigm shift in materials science and engineering [...] Full article

(This article belongs to the Special Issue Advanced Materials for Energy Applications: From Fuels to Batteries and Beyond)

24 pages, 2276 KiB

Open AccessArticle

Mid-Level Data Fusion Techniques of LC-MS and HS-GC-MS for Distinguishing Green and Ripe Forsythiae Fructus

by Qingling Xie, Hanwen Yuan, Shiqi Liu, Ling Liang, Jiangyi Luo, Mengyun Wang, Bin Li and Wei Wang

Molecules 2025, 30(7), 1404; https://doi.org/10.3390/molecules30071404 - 21 Mar 2025

Viewed by 66

Abstract

Forsythia suspensa is a crucial plant resource due to its considerable edible and medicinal value. Its fruit, named Forsythiae Fructus (FF), has been widely used in Traditional Chinese Medicine (TCM). According to the fruit maturity stage, FF is categorized into GFF (green Forsythiae [...] Read more.

Forsythia suspensa is a crucial plant resource due to its considerable edible and medicinal value. Its fruit, named Forsythiae Fructus (FF), has been widely used in Traditional Chinese Medicine (TCM). According to the fruit maturity stage, FF is categorized into GFF (green Forsythiae Fructus) and RFF (ripe Forsythiae Fructus). In this study, metabolomics based on UPLC-Q/Orbitrap MS and HS-GC-MS, combined with chemometric methods, was employed to differentiate GFF from RFF and identify potential differential metabolites. Additionally, the mid-level data fusion method was employed to integrate data from both techniques, and the performance of the OPLS-DA model (R²Y = 0.986, Q² = 0.974) surpassed that of the single HS-GC-MS technique (R²Y = 0.968, Q² = 0.930). Moreover, using the criteria of VIP > 1 and p-value < 0.05, 30 differential compounds were selected via mid-level data fusion, compared to the initial 61 differential compounds identified by single techniques, effectively reducing data noise and eliminating irrelevant variables. This study provides a comprehensive analysis of volatile and non-volatile compounds in FF, offering valuable insights into quality control and clinical differentiation between GFF and RFF. The findings highlight the potential use of multi-technology metabolomics in the quality control of TCM and offer new perspectives for future research on medicinal plants. Full article

(This article belongs to the Special Issue The Application of LC-MS in Pharmaceutical Analysis)

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Molecules, Volume 30, Issue 7 (April-1 2025) – 37 articles

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