Molecules

20 pages, 8258 KB

Open AccessArticle

Biomedical Applications of Chitosan-Coated Gallium Iron Oxide Nanoparticles Ga_xFe_(3−x)O₄ with 0 ≤ x ≤ 1 for Magnetic Hyperthermia

by Marta Orzechowska, Urszula Klekotka, Magdalena Czerniecka, Adam Tylicki, Dmytro Soloviov, Arkadiusz Miaskowski and Katarzyna Rećko

Molecules 2026, 31(1), 177; https://doi.org/10.3390/molecules31010177 - 2 Jan 2026

Abstract

Nanoparticles based on gallium ferrite are explored as potential agents for magnetic fluid hyperthermia due to their magnetic performance and biocompatibility. In this study, Ga_xFe_3−xO₄ systems (0 ≤ x ≤ 1) were synthesized by co-precipitation of iron chlorides, [...] Read more.

Nanoparticles based on gallium ferrite are explored as potential agents for magnetic fluid hyperthermia due to their magnetic performance and biocompatibility. In this study, Ga_xFe_3−xO₄ systems (0 ≤ x ≤ 1) were synthesized by co-precipitation of iron chlorides, with part of the series modified by a chitosan shell. Structural analysis confirmed single-phase formation across the studied range, while microscopy revealed irregular morphology, broad size distribution, and aggregation into mass-fractal-like assemblies. Chitosan was observed to coat groups of particles rather than single crystallites. Under an alternating magnetic field, all samples exhibited efficient heating, with specific absorption rate values generally increasing with gallium content. The composition Ga_0.73Fe_2.27O₄ showed the highest SAR—83.4 ± 2.2 W/g at 2.8 mg/mL, 532 kHz, 15.3 kA/m, and SAR values rose with decreasing concentration. Cytotoxicity assays without magnetic activation indicated no harmful effect, while chitosan-coated nanoparticles enhanced fibroblast viability and lowered metabolic activity of HeLa cells. Higher Ga content (x = 0.66) combined with chitosan modification was identified as optimal for hyperthermia. The results demonstrate the biomedical potential of these nanoparticles, while emphasizing the need to reduce shape heterogeneity, aggregation, and sedimentation for improved performance. Full article

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37 pages, 1528 KB

Open AccessReview

Advances in Dysprosium Recovery from Secondary Sources: A Review of Hydrometallurgical, Biohydrometallurgicaland Solvometallurgical Approaches

by Ewa Rudnik

Molecules 2026, 31(1), 176; https://doi.org/10.3390/molecules31010176 - 2 Jan 2026

Abstract

Dysprosium is one of the most critical elements for global economies due to its essential role in the green energy transition. Although it is added in small quantities as an alloying element, dysprosium plays a crucial role in NdFeB magnets used in wind [...] Read more.

Dysprosium is one of the most critical elements for global economies due to its essential role in the green energy transition. Although it is added in small quantities as an alloying element, dysprosium plays a crucial role in NdFeB magnets used in wind turbines and industrial motors. On the other hand, the limited resources and production capacity of dysprosium contribute to supply shortages and raise concerns about its long-term availability. Therefore, there is a need for efficient techniques that will enable the recovery of dysprosium from secondary materials to bridge the gap between supply and demand while addressing the risks associated with securing a stable supply. This review focuses on (bio)hydrometallurgical and solvometallurgical methods for recovering dysprosium from key secondary sources such as spent NdFeB magnets, phosphogypsum, and coal ash. Although these wastes do not always contain high concentrations of dysprosium, they can have a simpler elemental composition compared to primary sources (a few tens or hundreds of ppm Dy) and are more readily available. Spent NdFeB magnets, with a few percent Dy, show the most promise for recycling. In contrast, coal fly ashes (with several ppm Dy), although widely available, bind dysprosium in an inert phase, requiring substantial pretreatment to enhance the release of the desired element. Phosphogypsum, while not yet a significant source of dysprosium (several ppm Dy), is increasingly recognized as a potential source for other rare earth elements. Although conventional hydrometallurgical methods are commonly used, these are typically unselective for dysprosium recovery, whereas unconventional solvometallurgical approaches show preferential extraction of dysprosium over base metals. Full article

29 pages, 1989 KB

Open AccessReview

Marine Macroalgal Polysaccharides in Nanomedicine: Blue Biotechnology Contributions in Advanced Therapeutics

by Renu Geetha Bai, Surya Sudheer, Amal D. Premarathna and Rando Tuvikene

Molecules 2026, 31(1), 175; https://doi.org/10.3390/molecules31010175 - 2 Jan 2026

Abstract

Marine macroalgae represent a versatile and sustainable platform within blue biotechnology, offering structurally diverse polysaccharides that are making significant contributions to next-generation therapeutical applications. Algae are rich sources of high-value biomolecules, including polysaccharides, vitamins, minerals, proteins, antioxidants, pigments and fibers. Algal biomolecules are [...] Read more.

Marine macroalgae represent a versatile and sustainable platform within blue biotechnology, offering structurally diverse polysaccharides that are making significant contributions to next-generation therapeutical applications. Algae are rich sources of high-value biomolecules, including polysaccharides, vitamins, minerals, proteins, antioxidants, pigments and fibers. Algal biomolecules are widely explored in modern pharmaceuticals due to their range of physiochemical and biological properties. Recently, algal polysaccharides have gained increasing attention in nanomedicine due to their biocompatibility, biodegradability and tunable bioactivity. The nanomedical applications of algal polysaccharides pertain to their anti-coagulant, antiviral, anti-inflammatory, antimicrobial and anti-cancer properties. In this review, we discuss some major macroalgal polysaccharides, such as agar, agarose, funoran, porphyran, carrageenan, alginate and fucoidan, as well as their structure, uses, and applications in nanomedical systems. Both sulfated and non-sulfated polysaccharides demonstrate significant therapeutic properties when engineered into their nanotherapeutic forms. Previous studies show antimicrobial potential of 80–90% antiviral activity > 70%, significant anticoagulant activity, and excellent anticancer responses (up to 80% reductions in cancer cell viability have been reported in nanoformulated versions of polysaccharides). This review discusses structure–function relationships, bioactivities, nanomaterial synthesis and nanomedical applications (e.g., drug delivery, tissue engineering, biosensing, bioimaging, and nanotheranostics). Overall, this review reflects the potential of algal polysaccharides as building blocks in sustainable biomedical engineering in the future healthcare industry. Full article

(This article belongs to the Special Issue Algal Biomolecules for Food and Pharmaceutical Innovations: Extraction, Characterization and Applications)

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13 pages, 1272 KB

Open AccessArticle

Organ-Specific Diversity of Secoiridoids in Ligustrum japonicum Thunb.

by Sang Won Yeon, Qing Liu, Hak Hyun Lee, Se Jeong Kim, Su Hyeon Lee, Mun-Ock Kim, Bang Yeon Hwang and Mi Kyeong Lee

Molecules 2026, 31(1), 174; https://doi.org/10.3390/molecules31010174 - 2 Jan 2026

Abstract

Ligustrum japonicum Thunb. (Oleaceae) has long been valued for the medicinal properties. Its fruits are traditionally utilized, while the leaves and branches are generally discarded after fruit harvest. These aerial parts therefore represent underutilized by-products whose phytochemical profiles remain insufficiently characterized. To elucidate [...] Read more.

Ligustrum japonicum Thunb. (Oleaceae) has long been valued for the medicinal properties. Its fruits are traditionally utilized, while the leaves and branches are generally discarded after fruit harvest. These aerial parts therefore represent underutilized by-products whose phytochemical profiles remain insufficiently characterized. To elucidate the organ-specific chemical diversity and assess the potential value of these underutilized parts, a comparative analysis of the fruits, leaves, and branches was performed using HPLC–MS/MS combined with GNPS-based molecular networking, with a particular focus on secoiridoids, the characteristic metabolites of the Oleaceae family. This approach revealed substantial overlap as well as distinct variations in secoiridoid profiles among the three plant organs. Chromatographic separation yielded 14 secoiridoid derivatives shared across all organs. In addition, four previously undescribed secoiridoids were isolated and identified through spectroscopic analyses: secoligunosides A (1) and B (2) from the leaves and secoligunosides C (3) and D (4) from the branches. Among the major identified secoiridoids, oleuropein (10), 8Z-nüezhenide (17), and GL-3 (18) exhibited weak proliferative activity, showing an approximately 10–20% increase compared to control, on human dermal papilla cells. Collectively, these findings demonstrate that the leaves and branches not only contain key secoiridoids found in the fruits but also harbor unique metabolites, highlighting their value as alternative or complementary medicinal resources. The underutilized parts of L. japonicum therefore represent promising sources of natural products and warrant further investigation for future therapeutic applications. 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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24 pages, 8627 KB

Open AccessArticle

{Zn^II₂} and {Zn^IIAu^I} Metal Complexes with Schiff Base Ligands as Potential Antitumor Agents Against Human Glioblastoma Multiforme Cells

by Lora Dyakova, Tanya Zhivkova, Abedulkadir Abudalleh, Daniela C. Culita, Teodora Mocanu, Augustin M. Madalan, Anamaria Hanganu, Gabriela Marinescu, Emanuil Naydenov and Radostina Alexandrova

Molecules 2026, 31(1), 173; https://doi.org/10.3390/molecules31010173 - 1 Jan 2026

Abstract

The challenges of glioblastoma multiforme treatment are related to limitations in tumor removal surgery, its high heterogeneity and aggressiveness, development of resistance to standard therapy, the blood–brain barrier, and the side and toxic effects of the conventional antitumor agents used in clinical practice. [...] Read more.

The challenges of glioblastoma multiforme treatment are related to limitations in tumor removal surgery, its high heterogeneity and aggressiveness, development of resistance to standard therapy, the blood–brain barrier, and the side and toxic effects of the conventional antitumor agents used in clinical practice. Although new treatment strategies continue to emerge, progress remains slow and has not resulted in substantial improvements in patient survival. The main goal of research in recent years has been aimed at developing ways to deal with all these challenges. One of the ways to improve the control of glioblastomas is the introduction of effective new antitumor agents. Metal complexes represent a particularly promising class of compounds in this context. This is why the aim of this study was to assess the effects of six homo- and heterometallic coordination compounds bearing Schiff base ligands—[Zn₂(Ampy)(µ-OH)(H₂O)₂](ClO₄)₂ (ZnAmpy), [Zn₂(Dmen)(µ-OH)(H₂O)₂](ClO₄)₂ (ZnDmen), ¹_∞[{Zn₂(Ampy)(μ₃-OH)}₂(H₂O){μ-[Au(CN)₂]}](ClO₄)₃·THF·H₂O (ZnAmpyAu), [{Zn₂(Dmen)(μ-OH)}₂{μ-[Au(CN)₂]}{[Au(CN)₂]₂}](ClO₄)·H₂O (ZnDmenAu), ¹_∞[Zn(Salampy){μ-Au(CN)₂}] (ZnSalampyAu), and ¹_∞[Zn(Saldmen)(μ-Au(CN)₂}] (ZnSaldmenAu)—on the viability and proliferation of 8MGBA and U251MG human glioblastoma multiforme cells (HDmen and HAmpy are bicompartmental Schiff base ligands resulting from the condensation of 2,6-diformyl-p-cresol with N,N-dimethylethylenediamine and 2-(aminomethyl)pyridine, respectively, while HSaldmen and HSalampy are tridentate Schiff base ligands obtained via condensation of salicylaldehyde with N,N-dimethylethylenediamine and 2-(aminomethyl)pyridine, respectively). Among these compounds, ZnSaldmenAu is a new compound and is reported here for the first time. Cytotoxicity of the compounds was evaluated through analysis of cell viability, 2D/3D growth, cytopathological alterations, and induction of cell death. The results obtained by methods with different targets in cells and the associated mechanisms of action revealed that the compounds investigated show promising cytotoxic/potential antitumor activity in treated cells. Full article

(This article belongs to the Special Issue Exploring Schiff Base Ligands and Their Metal Complexes)

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21 pages, 616 KB

Open AccessArticle

Unlocking the Functional Value of European-Originated Chrysanthemum Hybrids: Phytochemical and Bioactivity Assessment

by Natalia Miler, Maciej Balcerek, Jakub Gębalski, Anita Woźny, Magdalena Wójciak, Ireneusz Sowa and Daniel Załuski

Molecules 2026, 31(1), 172; https://doi.org/10.3390/molecules31010172 - 1 Jan 2026

Abstract

Chrysanthemums are appreciated not only for their ornamental and medicinal attributes but also as edible plants long incorporated into teas, infusions, and culinary traditions. Yet, hybrid cultivars specifically adapted to European growing conditions remain poorly characterized with respect to their medicinal potential. In [...] Read more.

Chrysanthemums are appreciated not only for their ornamental and medicinal attributes but also as edible plants long incorporated into teas, infusions, and culinary traditions. Yet, hybrid cultivars specifically adapted to European growing conditions remain poorly characterized with respect to their medicinal potential. In this study, we investigated the phytochemical composition, antioxidant properties, and enzyme-inhibitory activities of inflorescences of four field-grown Chrysanthemum × morifolium ‘Donna’ × C. rubellum ‘Clara Curtis’ hybrids of European origin (CD 7, DC 19, DC 26, CD 46). Their profiles were compared with those of a Chinese tea cultivar (C. morifolium CHR18) and a commercial herbal product (CH B). Chemical constituents were analyzed using GC–MS and LC–MS, while antioxidant activity was evaluated by FRAP, CUPRAC, DPPH, ABTS, and iron-chelating assays; hyaluronidase (HYAL) and butyrylcholinesterase (BChE) inhibition were also assessed. A total of 61 volatile compounds were identified, with several terpenoids—such as chrysanthenone and verbenone—occurring exclusively in the European hybrids. CHR 18 possessed the highest flavonoid and phenolic acid levels, whereas hybrid CD 46 exhibited the most pronounced overall antioxidant performance. Hyaluronidase inhibition was strongest in DC 26 and CD 46 (60–62%), surpassing both reference samples, while BChE inhibition remained generally low. Overall, the results highlight that C. morifolium × C. rubellum hybrids developed for cultivation in the temperate European climate offer a unique combination of phytochemical richness, robust antioxidant activity, and noteworthy enzyme inhibition. These traits underscore their promise as emerging functional chrysanthemum resources and support future applications in European herbal products, nutraceutical development, and region-specific functional food innovation. Full article

(This article belongs to the Special Issue Medicinal Value of Natural Bioactive Compounds and Plant Extracts, 3rd Edition)

16 pages, 1767 KB

Open AccessArticle

Unveiling Fermentation Effects on the Functional Composition of Taiwanese Native Teas

by Wei-Ting Hung, Chih-Chun Kuo, Jheng-Jhe Lu, Fu-Sheng Yang, Yu-Ling Cheng, Yi-Jen Sung, Chiao-Sung Chiou, Hsuan-Han Huang, Tsung-Chen Su, Hsien-Tsung Tsai and Kuan-Chen Cheng

Molecules 2026, 31(1), 171; https://doi.org/10.3390/molecules31010171 - 1 Jan 2026

Abstract

Tea’s chemical composition is influenced by cultivar, harvest maturity, and growing environment; however, processing remains the dominant factor shaping final quality. Despite the diversity of Taiwanese native teas, systematic comparisons of functional components across multiple manufacturing stages remain limited. In this study, nine [...] Read more.

Tea’s chemical composition is influenced by cultivar, harvest maturity, and growing environment; however, processing remains the dominant factor shaping final quality. Despite the diversity of Taiwanese native teas, systematic comparisons of functional components across multiple manufacturing stages remain limited. In this study, nine representative Taiwanese teas were evaluated at four key processing stages—green tea (G), enzymatic fermentation (oxidative fermentation, F), semi-finished tea prior to roasting (S), and completed tea (C)—to clarify how enzymatic oxidation, rolling, and roasting alter major bioactive constituents. Green-tea-stage samples exhibited clear cultivar-dependent profiles: large-leaf cultivars contained higher catechins and gallic acid, whereas bud-rich small-leaf teas showed elevated caffeine and amino acids, with amino acids further enhanced at higher elevations. Fermentation intensity governed the major chemical transitions, including catechin depletion, gallic acid formation, accumulation of early stage catechin-derived paired oxidative polymerization compounds (POPCs), and pronounced increases in theasinensins in heavily fermented teas. L-theanine decreased most markedly in teas subjected to prolonged withering. Roasting further reduced amino acids but had minimal influence on caffeine, while rolling effects varied by tea type. Overall, this study provides the first stage-resolved chemical map of Taiwanese native teas, offering practical insights for optimizing processing strategies to enhance functional phytochemical profiles. Full article

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

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23 pages, 1747 KB

Open AccessArticle

The Use of Benzoin as a Privileged Structure: Synthesis, Characterization, Crystalline Form and an In Vitro Biological Evaluation of 1,2-Diphenyl-2-[1,2,3]triazol-1-yl-ethanol Derivatives

by Noé Martínez-Romero, Mario Valle-Sánchez, Marco A. García-Eleno, Carlos A. González-González, David Corona-Becerril, Lizbeth Triana-Cruz, Diego Martínez-Otero, María Teresa Ramírez-Apan, David Morales-Morales, Jorge Andrés Ornelas-Guillén and Erick Cuevas-Yañez

Molecules 2026, 31(1), 170; https://doi.org/10.3390/molecules31010170 - 1 Jan 2026

Abstract

A collection of 40 derivatives of 1,2-diphenyl-2-[1,2,3]triazol-1-yl-ethanol was obtained through a sequence of reactions, starting with benzoin as the initial raw material and using the CuAAC reaction as the key step in this process. The structure of a pair of these compounds was [...] Read more.

A collection of 40 derivatives of 1,2-diphenyl-2-[1,2,3]triazol-1-yl-ethanol was obtained through a sequence of reactions, starting with benzoin as the initial raw material and using the CuAAC reaction as the key step in this process. The structure of a pair of these compounds was ultimately corroborated by single-crystal X-ray diffraction studies, which also reveals important O-H···N interactions. The antimicrobial activity of synthesized 1,2,3-triazoles was assessed against strains that include Candida albicans and Staphylococcus aureus. The antiproliferative properties of some of these novel compounds were also tested using a variety of tumor cell lines, including U251 (human glioblastoma), PC-3 (human prostate cancer cell line), K562 (human leukemia), HCT-15 (human colorectal adenocarcinoma), MCF-7 (human breast adenocarcinoma), and SKLU (human lung adenocarcinoma). Full article

(This article belongs to the Special Issue A Themed Issue in Honor of the 20th Anniversary of the Mexican Academy of Organic Chemistry (AMQO))

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17 pages, 1787 KB

Open AccessArticle

Antioxidant and Erythroprotective Effects of C-Phycocyanin from the Cyanobacterium Spirulina sp. in Attenuating Oxidative Stress Induced by Peroxyl Radicals

by Cinthia Jael Gaxiola-Calvo, Diana Fimbres-Olivarría, Ricardo Iván González-Vega, Yaeel Isbeth Cornejo-Ramírez, Ariadna Thalía Bernal-Mercado, Saul Ruiz-Cruz, José de Jesús Ornelas-Paz, Miguel Ángel Robles-García, José Rogelio Ramos-Enríquez and Carmen Lizette Del-Toro-Sánchez

Molecules 2026, 31(1), 169; https://doi.org/10.3390/molecules31010169 - 1 Jan 2026

Abstract

Diseases caused by oxidative stress can present different susceptibilities depending on blood typing according to the ABO system and RhD factor, which turn out to be of great clinical importance. The use of antioxidants such as C-phycocyanin (a phycobiliprotein) could be an alternative [...] Read more.

Diseases caused by oxidative stress can present different susceptibilities depending on blood typing according to the ABO system and RhD factor, which turn out to be of great clinical importance. The use of antioxidants such as C-phycocyanin (a phycobiliprotein) could be an alternative to mitigate oxidative stress in the blood. Therefore, the objective of this study is to evaluate the antioxidant and erythroprotective activity of C-phycocyanin (C-PC) from Spirulina sp. against oxidative stress caused by peroxyl radicals, before and after in vitro digestion, comparing susceptibilities between blood groups. C-phycocyanin from Spirulina sp. was obtained commercially. The antioxidant capacity by ABTS+•, DPPH•, and FRAP assays of the bioaccessible fraction of C-PC increased compared to baseline in all assays. Samples appear to have high hydrogen atom transfer. C-PC is not cytotoxic in most blood groups. The AAPH hemolysis assays showed differences between blood groups, yielding results of 27.90, 22.60, 26.94, 27.66, 28.16, 28.34, and 24.91% hemolysis for O+, O−, A+, A−, B+, AB+, and AB−, respectively. Furthermore, in vitro digestion increased the erythroprotective effect in the bioavailable fraction in most blood groups, showing 37.12, 80.13, 5.48, 92.38, 67.93, 80.30, and 76.49% inhibition of hemolysis in O+, O−, A+, A−, B+, AB+, and AB−, respectively. These results demonstrate the biotechnological and biomedical potential of phycobiliproteins as safe candidates for the development of nutraceuticals and functional foods aimed at preventing oxidative damage. Full article

(This article belongs to the Special Issue Analytical Insights into Bioactive Compounds in Pharmaceutical Formulations)

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22 pages, 808 KB

Open AccessReview

Platinum-Based Cytostatics Used in Oncology with Respect to Environmental Fate and Innovative Removal Strategies of Their Metabolites

by Rafał Olchowski, Kinga Morlo and Ryszard Dobrowolski

Molecules 2026, 31(1), 168; https://doi.org/10.3390/molecules31010168 - 1 Jan 2026

Abstract

Pt complexes have been used in human and veterinary oncology for more than 50 years and represent one of the most significant groups of cytostatics. There are a lot of Pt-based compounds, such as cisplatin, carboplatin and oxaliplatin, which exhibit high efficiency against [...] Read more.

Pt complexes have been used in human and veterinary oncology for more than 50 years and represent one of the most significant groups of cytostatics. There are a lot of Pt-based compounds, such as cisplatin, carboplatin and oxaliplatin, which exhibit high efficiency against many tumors. Their broad application in oncology medicine and improper waste disposal induce environmental pollution by platinum cytostatics and their metabolites. They can cause toxic effects to fauna and flora, even at low concentration levels. Currently used technologies for wastewater treatment are not sufficient in the case of platinum-based metabolites. Their high resistance and toxicity of their degradation byproducts pose a serious problem. In this review, currently applied platinum-based cytostatics, their possible metabolic mechanisms, environmental impact and technological methods for their removal from wastewater and patients’ urine are summarized. Special attention is paid to adsorption methods. Full article

(This article belongs to the Special Issue Innovative Approaches to Sustainable Wastewater Treatment—Recent Developments in Hazardous Pollutants Removal)

23 pages, 2340 KB

Open AccessArticle

Effects of Chlorogenic Acid on Cellular Senescence in an In Vitro Model of 3T3-L1 Murine Adipocytes

by Maria Sofia Molonia, Federica Lina Salamone, Santi Trischitta, Antonella Saija, Francesco Cimino and Antonio Speciale

Molecules 2026, 31(1), 167; https://doi.org/10.3390/molecules31010167 - 1 Jan 2026

Abstract

^‡ These authors share the senior authorship [...] Full article

19 pages, 1426 KB

Open AccessArticle

Gingerol-Enriched Ginger Extract Effects on Anxiety-like Behavior in a Neuropathic Pain Model via Colonic Microbiome-Neuroimmune Modulation

by Roberto Mendóza, Julianna M. Santos, Xiaobo Liu, Moamen M. Elmassry, Guangchen Ji, Takaki Kiritoshi, Volker Neugebauer and Chwan-Li Shen

Molecules 2026, 31(1), 166; https://doi.org/10.3390/molecules31010166 - 1 Jan 2026

Abstract

Growing evidence has revealed that gut dysbiosis is associated with the development of anxio-depressive disorders through mechanisms that involve neuroimmune signaling, neurotransmitter changes, and neuroplasticity in the brain. This study investigated the effects of gingerol-enriched ginger (GEG) on specifically anxiety-related neuroinflammation-, neuroimmunity-, neuroplasticity-, [...] Read more.

Growing evidence has revealed that gut dysbiosis is associated with the development of anxio-depressive disorders through mechanisms that involve neuroimmune signaling, neurotransmitter changes, and neuroplasticity in the brain. This study investigated the effects of gingerol-enriched ginger (GEG) on specifically anxiety-related neuroinflammation-, neuroimmunity-, neuroplasticity-, neurotransmission-, and neurotoxicity-associated genes in different brain regions, as well as on alterations linked to colonic microflora-driven dysbiosis, in the spinal nerve ligation (SNL) rat model of neuropathic pain (NP). Twenty-seven male rats were assigned to 3 groups: sham, SNL, and SNL-treated with GEG at 200 mg/kg body weight (SNL+200GEG) via oral gavage for 5 weeks. Anxiety-like behavior was assessed on the elevated plus maze (EPM). mRNA expression was assessed by qRT-PCR using respective primers. Correlation between behavioral parameters and colonic microbiome composition was analyzed using the Spearman rank correlation. The SNL+200GEG group demonstrated decreased anxiety-like behavior in the SNL model. Compared to the SNL group, the SNL+200GEG group had increased mRNA expression of NRF2 (amygdala: left), LXRα (amygdala: both sides), and CX3CR1 (amygdala: both sides, hippocampus: right). GEG modulated neuroplasticity as shown by increased gene expression of PGK1 (amygdala: right, hippocampus: both sides), MEK1 (frontal cortex: both sides), LDHA (frontal cortex: both sides), GPM6A (frontal cortex: both sides, amygdala: right, hippocampus: right, and hypothalamus), and GLUT1 (amygdala: right) as well by decreased gene expression of HIF1α (in all brain regions except for the hypothalamus). GEG modulated neurotransmission via clearance of excessive glutamate release as suggested by increased gene expression of SLC1A3 (frontal cortex: both sides, hippocampus: right) and via augmenting mGluR5 signaling as shown by increased gene expression of GRM5 (hippocampus: both sides, hypothalamus) as well as downregulation of KMO, HAAO, GRIN2B, and GRIN2C influencing downstream serotonergic neurotransmission and NMDA receptor-mediated glutamatergic pathways in different brain regions. GEG further alleviated neurotoxicity through downregulated gene expression of SIRT1, KMO, IDO1, and HAAO in different brain regions. Moreover, the increased relative abundance of Bilophila spp., accompanied by decreased time spent in the EPM open arms, suggests that increased Bilophila abundance increases anxiety-like behavior. GEG supplementation mitigated anxiety-like behavior in male rats with NP, at least in part, by reducing SNL-induced inflammatory sequelae-related mRNA gene expression in different brain regions. In addition, there is a positive correlation between the abundance of Bilophila wadsworthia and the degree of anxiety-like behavior. Full article

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

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15 pages, 1638 KB

Open AccessArticle

Screening of Bioactive Microalgae from Freshwaters, Collected in Hue, Vietnam: Cytotoxic Constituents from Dolichospermum smithii HU04

by Nguyen Thi Minh Hang, Nguyen Thi Thu Ha, Hoang Duc Manh, Duong Thi Thuy, Hoang Thi Quynh, Nguyen Thi Thu Lien, Nguyen Thi Tu Oanh, Tran Huu Giap, Buu Huu Tai, Doan Thi Mai Huong, Ngo Quoc Anh and Nguyen Xuan Nhiem

Molecules 2026, 31(1), 165; https://doi.org/10.3390/molecules31010165 - 1 Jan 2026

Abstract

Background/Objectives: Microalgae are recognized as prolific producers of bioactive metabolites with pharmaceutical potential. This study aimed to isolate and characterize cytotoxic constituents from selected cytotoxic microalgae, collected in Hue city, Vietnam. Methods: Microalgal samples were collected from freshwater bodies, morphologically identified, and maintained [...] Read more.

Background/Objectives: Microalgae are recognized as prolific producers of bioactive metabolites with pharmaceutical potential. This study aimed to isolate and characterize cytotoxic constituents from selected cytotoxic microalgae, collected in Hue city, Vietnam. Methods: Microalgal samples were collected from freshwater bodies, morphologically identified, and maintained in laboratory culture. Thirteen strains were successfully isolated and cultivated in BG11, Z8, and BBM media to determine optimal growth conditions. Cytotoxic effects of extracts/compounds were determined using the sulforhodamine B assay on human lung cancer (SK-LU-1) and human liver cancer (HepG2) cell lines. The methanol extract was partitioned with n-hexane and CH₂Cl₂, followed by extensive chromatographic separation and HPLC purification to afford twelve compounds, including two new and ten known compounds. The structures were elucidated by HR-ESI-MS and NMR spectra, chemical methods, and comparing compounds in the literature. Results: From the phytoplankton samples collected across six freshwater bodies in Hue city, Vietnam, thirteen microalgal strains were successfully isolated and purified under laboratory conditions. These strains were morphologically and taxonomically identified to be Microcystis aeruginosa HU05, Microcystis viridis HU13, Anabaena circinalis HU08, Aphanizomenon flos-aquae HU02, Dolichospermum smithii HU04, Calothrix braunii HU14, Nostoc muscorum HU12, Nostoc punctiforme HU11, Raphidiopsis raciborskii HU03, Lyngbya spiralis HU15, Planktothrix stagnina HU16, Phormidium subtilis HU06, and Scenedesmus quadricauda HU07. All methanol extracts of those microalgae were evaluated for cytotoxic activity. The MeOH extracts of M. viridis (HU13) and D. smithii (HU04) exhibited significant cytotoxic effects, with IC₅₀ values of 6.19 ± 0.80 and 4.89 ± 0.76 µg/mL for M. viridis, and 9.51 ± 0.84 and 8.32 ± 0.94 µg/mL for D. smithii against SK-LU-1 and HepG2 cell lines, respectively. Furthermore, chemical studies of D. smithii HU04 led to the isolation of two new compounds, smithioside A (1) and smithioside B (2) and ten known ones, 3,4,5-trimethoxyphenyl-1-O-β-D-glucopyranoside (3), 4′-hydroxy-3′-methoxyphenol-β-D-[6-O-(4″-hydroxy-3″,5″-dimethoxylbenzoate)]-glucopyranoside (4), 4′-hydroxy-2′,6′-dimethoxyphenol 1-O-β-D-(6-O-syringoyl)glucopyranoside (5), mallophenol B (6), pisoninol II (7), guaiacylglycerol (8), (E)-asarone (9), deacetylsarmentamide B (10), (E)-2-hexenyl-β-D-glucopyranoside (11), and 5,6-dihydropyridin-2(1H)-one (12). The cytotoxic activity of all isolated compounds was also evaluated against SK-LU-1 and HepG2 cancer cell lines. Compound 12 showed the strongest activity, with IC₅₀ values of 9.13 ± 0.89 µM (SK-LU-1) and 7.64 ± 0.46 µM (HepG2). Compounds 5 and 6 exhibited moderate cytotoxic activity on both human cancer cell lines with IC₅₀ values ranging from 25.99 to 51.47 µM. Conclusions: These results highlight the potential of Dolichospermum smithii HU04 as a source of bioactive compounds, particularly in anticancer applications. These findings suggest that D. smithii HU04 extracts could be developed for therapeutic purposes targeting cancer. Full article

(This article belongs to the Special Issue Functional Evaluation of Bioactive Compounds from Natural Sources, 2nd Edition)

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9 pages, 3343 KB

Open AccessCommunication

Chemoselective Aza-Michael Addition of Enolizable Heterocyclic Imine-Thiols to Levoglucosenone

by Anastasia Mauger, Rubi Mahato, Zbigniew J. Witczak, Roman Bielski and Donald E. Mencer

Molecules 2026, 31(1), 164; https://doi.org/10.3390/molecules31010164 - 1 Jan 2026

Abstract

Heterocyclic sulfur and nitrogen containing compounds capable of forming an equilibrium: thiol/imine = thione/amine (N=C-S-H ⇌ H-N-C=S) were reacted with levoglucosenone (LG) in the presence of triethylamine. Unexpectedly, the only isolated products were the result of the aza-Michael addition. No S-adducts were [...] Read more.

Heterocyclic sulfur and nitrogen containing compounds capable of forming an equilibrium: thiol/imine = thione/amine (N=C-S-H ⇌ H-N-C=S) were reacted with levoglucosenone (LG) in the presence of triethylamine. Unexpectedly, the only isolated products were the result of the aza-Michael addition. No S-adducts were detected. All products were crystalline with good to excellent yields. The structure of products was determined using NMR, MS, and single-crystal X-ray analysis. Full article

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15 pages, 1767 KB

Open AccessArticle

Enhanced Dispersibility of Iron Oxide Nanoparticles Synthesized by Laser Pyrolysis with Isopropanol Vapors as Sensitizer

by Iulia Ioana Lungu, Florian Dumitrache, Anca Criveanu, Lavinia Gavrila-Florescu, Ana-Maria Banici, Iuliana Morjan, Razvan-Mihai Dumitrache and Bogdan Vasile

Molecules 2026, 31(1), 163; https://doi.org/10.3390/molecules31010163 - 1 Jan 2026

Abstract

The present study investigates the synthesis and dispersibility process of iron oxide nanoparticles using laser pyrolysis with isopropanol vapors as a sensitizer agent. Similar to previous experiments (iron oxide nanoparticles synthesized by laser pyrolysis using ethylene as sensitizer gas), iron pentacarbonyl (Fe(CO)₅ [...] Read more.

The present study investigates the synthesis and dispersibility process of iron oxide nanoparticles using laser pyrolysis with isopropanol vapors as a sensitizer agent. Similar to previous experiments (iron oxide nanoparticles synthesized by laser pyrolysis using ethylene as sensitizer gas), iron pentacarbonyl (Fe(CO)₅) was employed as an iron precursor; however, instead of the classic ethylene, isopropanol was chosen as a sensitizer, which indicated beneficial features (especially enhanced dispersibility in water) in the as-synthesized nanoparticles. Structural and elemental analysis confirmed the size range of the nanoparticles (nanometric), with crystallite sizes under 10 nm. Both raw nanoparticles, as well as the oleic acid stabilized ones, exhibited excellent colloidal stability in both water and organic fluids (Toluene, Chloroform, and DMSO): around 100 nm hydrodynamic diameter and more than 40 mV for zeta potential. The study highlights the advantages of using isopropanol as a sensitizer in the production of high-purity iron oxide nanoparticles from laser pyrolysis, particles that showcase superior dispersibility and functionalization potential. Full article

(This article belongs to the Special Issue Synthesis and Applications of Nanoparticles and Multifunctional Nanocomposites)

21 pages, 2105 KB

Open AccessArticle

Synthesis, Crystal Structure, Antitumor, and Antimicrobial Activity of Novel Copper(II) Complexes with a Coumarin Derivative Containing a Histamine Substituent

by Ewelina Namiecińska, Pawel Hikisz, Patryk Czapnik, Magdalena Małecka, Magdalena Grazul, Peter Mayer, Ingo-Peter Lorenz and Elzbieta Budzisz

Molecules 2026, 31(1), 162; https://doi.org/10.3390/molecules31010162 - 1 Jan 2026

Abstract

Copper(II) complexes have great potential as antitumor and antimicrobial agents, and their coumarin derivatives bearing histamine substituents possess versatile structural and biological properties. The present article describes the synthesis of novel copper(II)–coumarin–histamine complexes and ligands and their characterization by IR, NMR, X-ray diffraction, [...] Read more.

Copper(II) complexes have great potential as antitumor and antimicrobial agents, and their coumarin derivatives bearing histamine substituents possess versatile structural and biological properties. The present article describes the synthesis of novel copper(II)–coumarin–histamine complexes and ligands and their characterization by IR, NMR, X-ray diffraction, and elemental analysis. Their antimicrobial activity (MIC, MBC/MFC) was tested against 11 reference strains. Cytotoxicity was evaluated using the MTT assay against 15 selected cancer cell lines and normal HMEC-1 cells. It presents three new ligands and three new complexes with copper(II) ions and selected histamine-containing coumarin derivatives. The new copper(II) complexes demonstrated markedly higher anticancer activity than their corresponding ligands across all evaluated cancer cell lines. The highest anticancer activity against the Hep3B liver cancer cell line was demonstrated by the copper(II) complex (3b), which also showed the strongest inhibition of S. epidermidis ATCC 12228 and S. aureus ATCC 6538. The copper(II) ions play a crucial role in the antitumor activity of these derivatives. Despite limited antimicrobial effects, the tested complexes, particularly 3a and 3b, demonstrate promising anticancer potential, especially against the Hep3B cancer cell line. Only 3b demonstrated antimicrobial activity against S. epidermidis ATCC 12228 and S. aureus ATCC 6538. Full article

(This article belongs to the Special Issue Metal Ions and Metal Complexes in Medicinal Chemistry)

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17 pages, 2905 KB

Open AccessArticle

Unexpected Orange Photoluminescence from Tetrahedral Manganese(II) Halide Complexes with Bidentate Phosphanimines

by Domenico Piccolo, Jesús Castro, Valentina Beghetto, Daniele Rosa-Gastaldo and Marco Bortoluzzi

Molecules 2026, 31(1), 161; https://doi.org/10.3390/molecules31010161 - 1 Jan 2026

Abstract

Manganese(II) halide complexes with the general formula [MnX₂{(PhN=PPh₂)CH₂}], where X is bromine or iodine and (PhN=PPh₂)CH₂ is the bis-phosphanimine ligand 1,1′-methylenebis-(N,1,1-triphenylphosphanimine), were prepared and isolated. The structure of the two compounds was [...] Read more.

Manganese(II) halide complexes with the general formula [MnX₂{(PhN=PPh₂)CH₂}], where X is bromine or iodine and (PhN=PPh₂)CH₂ is the bis-phosphanimine ligand 1,1′-methylenebis-(N,1,1-triphenylphosphanimine), were prepared and isolated. The structure of the two compounds was determined by single-crystal X-ray diffraction, revealing an approximately tetrahedral geometry at the metal centre. Unlike structurally comparable compounds containing phosphine oxides or related [O=P]-donors in the coordination sphere, which commonly show green emissions, solid samples of [MnBr₂{(PhN=PPh₂)CH₂}] and [MnI₂{(PhN=PPh₂)CH₂}] exhibited orange emissions upon irradiation with UV light. The emission spectra resulted excitation-independent. Superimposable steady-state luminescence spectra were collected for both compounds as powders and crystals suitable for X-ray diffraction. The excitation spectra and the ligand→metal antenna effect were affected by the coordinated halide, and only [MnBr₂{(PhN=PPh₂)CH₂}] showed bright luminescence under near-UV irradiation. Either ligand- or metal-centred transitions can account for the observed luminescence, and the luminescence decay curves were consistent with a multiplicity change from the excited to the ground state, with excited-state lifetimes in the range of hundreds of microseconds. Attempts to rationalize the unexpected luminescence were carried out based on DFT calculations. Full article

(This article belongs to the Special Issue Organometallic Compounds: Design, Synthesis and Application: 2nd Edition)

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47 pages, 454 KB

Open AccessArticle

Selenium (IV) and Sulphur (VI) as Elements Modifying Plant Quality: Content of Selenium and Sulphur Forms in Wheat

by Marzena S. Brodowska, Magdalena Kurzyna-Szklarek and Mirosław Wyszkowski

Molecules 2026, 31(1), 160; https://doi.org/10.3390/molecules31010160 - 1 Jan 2026

Abstract

In order to achieve high-quality yields, it is essential to provide plants with the necessary nutrients, including selenium (Se) and sulphur (S), to meet their nutritional requirements. This study aimed to determine the effect of selenium (0, 10 and 20 g Se ha [...] Read more.

In order to achieve high-quality yields, it is essential to provide plants with the necessary nutrients, including selenium (Se) and sulphur (S), to meet their nutritional requirements. This study aimed to determine the effect of selenium (0, 10 and 20 g Se ha⁻¹) and the date of its application (in the tillering phase and in the stem elongation phase) and sulphur application (0, 15 and 30 kg S ha⁻¹) on the content of selenium and various forms of sulphur (total sulphur, sulphate sulphur and organic sulphur) and the N:S ratio in winter spelt wheat and winter common wheat. The research hypothesis assumed that different doses of selenium and sulphur and the timing of their application would have a beneficial effect on the Se and S content in the grain and straw of spelt wheat and common wheat. Selenium fertilisation significantly increased the content of this element in the grain of spelt wheat and common wheat. The concentration of selenium was also influenced by the timing of its application in the plant growth environment. However, the dose of selenium and the timing of its application were not associated with significant changes in the content of both forms of sulphur in the tested plants. The experimental factors used did not contribute to the achievement of selenium levels toxic to humans and animals. The presence of sulphur in the growth environment of spelt wheat and common wheat was associated with an increase in the content of both total sulphur, sulphate sulphur and organic sulphur in their grain and straw, especially in spelt wheat straw by an average of 17%, 29% and 23%, respectively, and in common wheat straw by 26%, 18% and 57%, respectively. The sulphur content in the plant growth environment was not associated with a change in the selenium content in the grain of the tested plants. The results of our study suggest that the optimal dose of selenium for biofortification of humans and animals is 20 mg Se ha⁻¹ on clay soil, applied during the stem elongation phase of spelt and common wheat. Biofortification of wheat with selenium and sulphur is a good method of supplementing deficiencies of this element in the human diet. Full article

(This article belongs to the Special Issue Green Chemistry and Molecular Tools in Agriculture)

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18 pages, 1550 KB

Open AccessArticle

Ecological Prevalence and Non-Enzymatic Formation of Imidazolium Alkaloids on Moon Snail Egg Collars

by Karla Piedl, Caitlyn O. Agee, Anthony G. Tarulli, Rose Campbell, Paige Banks, Nicklas W. Buchbinder, R. Thomas Williamson and Emily Mevers

Molecules 2026, 31(1), 159; https://doi.org/10.3390/molecules31010159 - 1 Jan 2026

Abstract

Microorganisms wage constant chemical battles against one another as they compete for space and scarce nutrients, particularly within animal-associated habitats. Here, binary assays were used to investigate chemical interactions among Flavobacteriaceae within Neverita delessertiana egg collars, a moon snail common to the Gulf [...] Read more.

Microorganisms wage constant chemical battles against one another as they compete for space and scarce nutrients, particularly within animal-associated habitats. Here, binary assays were used to investigate chemical interactions among Flavobacteriaceae within Neverita delessertiana egg collars, a moon snail common to the Gulf Coast. Analysis of 140 distinct pairings revealed eight that exhibited growth-inhibitory activity. Chemical evaluation of the crude extract from Cellulophaga omnivescoria EM610, which inhibited the growth of three other Flavobacteriaceae, resulted in the isolation of bacillimidazoles A (1) and E (2), two previously characterized metabolites, isolated from a marine Bacillus species. Further work demonstrated that these compounds are readily formed spontaneously by condensation of 2,3-butanedione with phenethylamine and/or tryptamine. Tandem mass spectrometry analysis of the chemical extracts of individual moon snail egg collars revealed the presence of bacillimidazole A in 62% of the egg collars. Full article

(This article belongs to the Special Issue A Theme Issue in Honor of Professor Gary E. Martin's 75th Birthday)

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