Molecules

18 pages, 2851 KB

Open AccessArticle

Anti-Neuroinflammatory Cannabinoid Acids as a New Therapeutic Approach for Multiple Sclerosis

by Nitsan Sharon, Yvonne Ventura, Nirit Bernstein, Jonathan Gorelick, Shimon Ben-Shabat and Sigal Fleisher-Berkovich

Molecules 2026, 31(7), 1227; https://doi.org/10.3390/molecules31071227 - 7 Apr 2026

Viewed by 915

Abstract

Neuroinflammation is a hallmark of multiple sclerosis (MS). MS is marked by glial cell activation, autoreactive T cells, and the release of pro-inflammatory cytokines and free radicals. Current therapeutic strategies aim to modulate the immune response using disease-modifying therapies, to slow disease progression. [...] Read more.

Neuroinflammation is a hallmark of multiple sclerosis (MS). MS is marked by glial cell activation, autoreactive T cells, and the release of pro-inflammatory cytokines and free radicals. Current therapeutic strategies aim to modulate the immune response using disease-modifying therapies, to slow disease progression. The specific aims of this study were: (a) to investigate the effect of cannabinoid acids on the release of glial neuroinflammatory mediators, (b) to examine the effect of intraperitoneally administered cannabinoid acids on symptoms of MS, and (c) to evaluate their effects on microglial and astrocyte activation and CD4⁺ T cell infiltration into the spinal cords of MS mice. Exposure of BV2 microglia to cannabinoid acids attenuated lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase by 40–90% it also reduced the release of nitric oxide and interleukin-17A. Among the cannabinoid acids tested, cannabidiolic acid (CBDA) significantly increased tumor necrosis factor alpha (TNFα) secretion by up to 40% in LPS-stimulated BV2 cells. Intraperitoneal administration of CBDA also resulted in a twofold increase in TNFα secretion in splenocytes isolated from MS mice, compared to untreated MS controls. This study provides evidence that CBDA significantly reduces neurological scores, while both cannabinoid acids attenuate microgliosis, astrogliosis, and CD4+ T cell migration in lumbar spinal cord sections of MS mice. These compounds cross the blood–brain barrier (BBB) and act directly within the central nervous system. The consistent elevation of TNFα in the presence of CBDA across three experimental models suggests a distinctive immunomodulatory role for CBDA, with potential therapeutic implications in MS. Full article

(This article belongs to the Special Issue Back to Nature: Pharmacological Activities of Phytochemicals Isolated from Medicinal Plants)

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13 pages, 1869 KB

Open AccessArticle

Caffeic Acid, Reduced Glutathione, and Ferric Iron Addition Effects on the Redox Potential of Model Wine Solutions

by William Jordan Wright, Dallas J. Parnigoni, Sean Kuster, James Nelson, Robert E. Coleman and L. Federico Casassa

Molecules 2026, 31(7), 1226; https://doi.org/10.3390/molecules31071226 - 7 Apr 2026

Viewed by 612

Abstract

To further understand redox mechanisms occurring in wine, caffeic acid (CAF, 150 mg/L) and/or glutathione (GSH, 150 mg/L) were added to a model wine solution, followed by ferric iron (2 mg/L Fe(III), added as 10 mg/L Fe(III) chloride hexahydrate), while monitoring the oxidation–reduction [...] Read more.

To further understand redox mechanisms occurring in wine, caffeic acid (CAF, 150 mg/L) and/or glutathione (GSH, 150 mg/L) were added to a model wine solution, followed by ferric iron (2 mg/L Fe(III), added as 10 mg/L Fe(III) chloride hexahydrate), while monitoring the oxidation–reduction potential (ORP, redox potential). Caffeic acid produced only modest ORP changes. In contrast, glutathione and caffeic acid + glutathione additions dropped the ORP from 243 mV and 238 mV, respectively, to the same post-addition value of 189 mV, suggesting that glutathione dictated the ORP, while caffeic acid showed no effect. The quinone of caffeic acid (assumed as changes in AU at 420 nm), was not detected, suggesting caffeic acid did not participate in oxidation reactions under wine conditions under superfluous amounts of dissolved oxygen (DO). After the addition of Fe(III), ORP increased to similar values across all treatments: 266 mV (FE), 269 mV (CAF), 284 mV (GSH), and 242 mV (CAF + GSH), suggesting that the Fe(II)/Fe(III) redox couple dominated the ORP electrode response. CAF + GSH produced the steepest ORP decline after the addition of Fe(III) chloride hexahydrate (β (slope of the ORP) = −0.7082), significantly steeper than FE (β = −0.3051; p = 0.0032) and GSH (β = −0.4643; p = 0.0496), suggesting synergistic radical quenching and metal redox cycling. Photo-Fenton-like reactions likely contributed to slight decreases in the ORP over time. In conclusion, glutathione strongly lowered the ORP, Fe(III) increased the ORP across treatments, and caffeic acid had minimal impact on the ORP under model wine conditions. Full article

(This article belongs to the Special Issue Current Research in Wine Chemistry and Analysis)

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19 pages, 1445 KB

Open AccessArticle

Chemical Characterization, Evaluation of Antimicrobial Potential, and Cytotoxic Activity of Thuja occidentalis L. and Myrtus communis L. Essential Oils for Topical Applications

by Elena Dănilă, Ioana Cristina Marinas, Madalina Diana Gaboreanu, Vlad Andrei Neacșu, Irina Titorencu, Minodora Maria Marin, Durmuş Alpaslan Kaya, Nafiz Çeliktaş, Mădălina Albu Kaya and Raluca Țuțuianu

Molecules 2026, 31(7), 1225; https://doi.org/10.3390/molecules31071225 - 7 Apr 2026

Cited by 1 | Viewed by 756

Abstract

In this study, we investigated the chemical composition, antimicrobial and antibiofilm activities, and cytotoxicity of Thuja occidentalis L. (thuja) and Myrtus communis L. (myrtle) essential oils (EOs) to evaluate their potential as natural alternatives for topical applications. Thuja EOs were extracted from fresh [...] Read more.

In this study, we investigated the chemical composition, antimicrobial and antibiofilm activities, and cytotoxicity of Thuja occidentalis L. (thuja) and Myrtus communis L. (myrtle) essential oils (EOs) to evaluate their potential as natural alternatives for topical applications. Thuja EOs were extracted from fresh and dried leaves and cones, while myrtle EO was extracted from fresh leaves. GC-MS analysis revealed that myrtle EO was rich in oxygenated monoterpenes (58.2%), predominantly eucalyptol (41.86%) and α-pinene (20.98%). In contrast, thuja EOs were dominated by monoterpene hydrocarbons (55–82%), with α-pinene as the major component (29–66%), and their composition varied markedly with plant organ and moisture state. Myrtle EO displayed the most potent and broad-spectrum antimicrobial activity, with MIC values as low as 3.096 µL/mL against Staphylococcus aureus and Escherichia coli, and effectively inhibited microbial adherence. Thuja EOs showed selective activity, particularly against Gram-positive bacteria and Candida parapsilosis, with EOs extracted from fresh leaves and cones exhibiting the lowest MICs (1.95–7.8 µL/mL). All EOs did not show cytotoxicity to human keratinocytes at concentrations ≤125 µg/mL and, when diluted to 0.05%, indicated excellent skin compatibility in human patch tests. This study suggests that myrtle and thuja EOs, particularly myrtle, are promising and safe natural antimicrobial agents for dermatological and cosmetic formulations. Full article

(This article belongs to the Special Issue Plant-Based Food Science: Chemical Composition and Biological Activity—2nd Edition)

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25 pages, 3669 KB

Open AccessArticle

Hydrothermal Conversion of Annatto Seed Waste (Bixa orellana) into Functional Hydrochar: Synthesis, Characterization, and Adsorption Mechanism of Tetracycline

by Diana Guaya, Linda Jadán and José Luis Cortina

Molecules 2026, 31(7), 1224; https://doi.org/10.3390/molecules31071224 - 7 Apr 2026

Viewed by 526

Abstract

Agroindustrial residues represent an abundant and underutilized source of carbon-rich materials for environmental remediation. In this study, annatto processing waste (Bixa orellana), a largely unexplored lignocellulosic by-product generated during pigment extraction, was converted into hydrochar via hydrothermal carbonization at 200 °C [...] Read more.

Agroindustrial residues represent an abundant and underutilized source of carbon-rich materials for environmental remediation. In this study, annatto processing waste (Bixa orellana), a largely unexplored lignocellulosic by-product generated during pigment extraction, was converted into hydrochar via hydrothermal carbonization at 200 °C for 3 h. The resulting hydrochar (HC-AW) exhibited a predominantly amorphous carbon structure with retained oxygen-containing surface functionalities, and a solid yield of 44%, indicating efficient biomass conversion under subcritical conditions. Adsorption performance toward tetracycline was evaluated through pH-dependent experiments, kinetic modeling, equilibrium isotherms, and thermodynamic analysis. Maximum adsorption occurred under near-neutral conditions (pH ≈ 7), consistent with the interplay between tetracycline speciation and the hydrochar surface charge (pH_PZC ≈ 6.3), highlighting its potential applicability under realistic water treatment conditions without pH adjustment. Kinetic data were well described by the pseudo-second-order model, while equilibrium results were best fitted by the Langmuir model, with a maximum adsorption capacity of 14.94 mg g⁻¹ at 30 °C. Thermodynamic analysis indicated a spontaneous and slightly endothermic adsorption process. Overall, the results highlight the potential of annatto-derived hydrochar as a low-cost adsorbent and provide insight into the relationship between surface properties and adsorption behavior governing antibiotic removal from aqueous systems. Full article

(This article belongs to the Topic Biomass for Energy, Chemicals and Materials)

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37 pages, 3999 KB

Open AccessReview

Comparative Review of O,O′-, N,O-, and N,N′-Bidentate Ligands: Structural and Electronic Properties of β-Diketones, Enaminones, and β-Diketiminates

by Jeanet Conradie

Molecules 2026, 31(7), 1223; https://doi.org/10.3390/molecules31071223 - 7 Apr 2026

Viewed by 791

Abstract

Bidentate ligands, derived from the 1,3-dicarbonyl framework, play a central role in coordination chemistry, catalysis, and materials science due to their tuneable donor properties and structural versatility. This review examines and compares three closely related ligand classes, β-diketones (O,O′ donors), imino-β-diketones or enaminones [...] Read more.

Bidentate ligands, derived from the 1,3-dicarbonyl framework, play a central role in coordination chemistry, catalysis, and materials science due to their tuneable donor properties and structural versatility. This review examines and compares three closely related ligand classes, β-diketones (O,O′ donors), imino-β-diketones or enaminones (N,O donors), and di-imino-β-diketones or β-diketiminates (N,N′ donors), to elucidate how systematic substitution of oxygen by nitrogen affects structure and properties. The discussion integrates spectroscopic data (NMR and IR), crystallographic findings, electrochemical measurements, and density functional theory (DFT) calculations reported in the literature. Across these systems, tautomerism plays a decisive role, with conjugation-stabilized enol or enamine forms generally preferred in solution and the solid state. Frontier molecular orbital analyses show extensive delocalization over the chelate backbone and, when present, aromatic substituents. Electrochemical studies reveal consistent correlations between experimental reduction potentials and calculated LUMO energies for O,O′-, N,O-, and N,N′-bidentate ligands. Overall, the comparison demonstrates that donor atom substitution within a conserved conjugated scaffold provides a systematic approach to tuning acidity, coordination behaviour, and redox properties, offering a coherent framework for understanding structure–property relationships in 1,3-dicarbonyl-derived chelating ligands. Full article

(This article belongs to the Special Issue N,O,S-Donor Ligands and Metal Complexes: From Structural Characterization to Biological and Catalytic Applications)

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22 pages, 4624 KB

Open AccessArticle

Application of Silibinin Oleate as a Nutraceutical Antioxidant for Improving the Quality of Sunflower Oil

by Cristina Adriana Dehelean, Cristian Oancea, Andreea-Adriana Neamtu, Vlad Enache, Victor Emil Alexa, Ileana Cocan, Mariana Suba, Maria-Alexandra Pricop, Alexandra Teodora Lukinich-Gruia, Călin Adrian Tatu and Ersilia Alexa

Molecules 2026, 31(7), 1222; https://doi.org/10.3390/molecules31071222 - 7 Apr 2026

Viewed by 623

Abstract

Sunflower oil is particularly prone to thermo-oxidative degradation due to its high content of polyunsaturated fatty acids, especially under high-temperature conditions. This study investigated the oxidative stability of sunflower oil heated at 180 °C for 4 and 8 h, focusing on the protective [...] Read more.

Sunflower oil is particularly prone to thermo-oxidative degradation due to its high content of polyunsaturated fatty acids, especially under high-temperature conditions. This study investigated the oxidative stability of sunflower oil heated at 180 °C for 4 and 8 h, focusing on the protective effect of silibinin oleate (SIL-O), a lipophilic polyphenolic derivative, compared to the synthetic antioxidant butylated hydroxytoluene (BHT). Oxidative changes were evaluated through peroxide value (PV), p-anisidine value (p-AV), and total oxidation value (TOTOX), while structural alterations were monitored using FTIR spectroscopy. Additionally, fatty acid composition was analyzed by GC-MS to assess compositional changes associated with oxidation. Thermal treatment led to increases in PV, p-AV, and TOTOX, indicating progressive oxidation, alongside a decrease in unsaturated fatty acids. FTIR analysis revealed characteristic changes, including a reduction in the unsaturation band (~3008 cm⁻¹), modifications in the ester carbonyl region (~1743 cm⁻¹), and the emergence of bands associated with cis–trans isomerization (~968–970 cm⁻¹). Strong correlations were observed between fatty acid degradation, FTIR indices, and oxidation parameters. Compared to the control, SIL-O inhibited oxidation in a dose-dependent manner. At 300 ppm, it outperformed BHT, demonstrating its potential as a natural antioxidant for enhancing the stability of sunflower oil during high-temperature processing. Full article

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

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17 pages, 47282 KB

Open AccessArticle

Differential Effects of Curcumin and Cordycepin on Oral Squamous Cell Carcinoma Cells: ROS-Mediated Cytotoxicity and Real-Time Morphological Analysis

by Bianca Voicu Balasea, Miruna-Silvia Stan, Radu Radulescu, Ana Cernega, Kersti Alm, Monica Musteanu, Florentina Rus, Alexandra Ripszky and Silviu Mirel Pituru

Molecules 2026, 31(7), 1221; https://doi.org/10.3390/molecules31071221 - 7 Apr 2026

Viewed by 759

Abstract

Oral squamous cell carcinoma (OSCC) remains a major clinical challenge, highlighting the need for novel therapeutic strategies. Natural bioactive compounds such as curcumin (Cu) and cordycepin (Co) have shown anticancer potential; however, their effects on cancer cell morphology and behavior remain incompletely characterized. [...] Read more.

Oral squamous cell carcinoma (OSCC) remains a major clinical challenge, highlighting the need for novel therapeutic strategies. Natural bioactive compounds such as curcumin (Cu) and cordycepin (Co) have shown anticancer potential; however, their effects on cancer cell morphology and behavior remain incompletely characterized. This study assessed the individual and combined effects of Cu and Co on oral squamous cell carcinoma cells (OECM-1) and normal human gingival epithelial cells (HGEpiC) over 24 and 48 h. Metabolic activity, membrane integrity, oxidative stress, apoptosis, and inflammatory responses were evaluated using MTT, LDH, ROS-H₂O₂, caspase 3/7, and NO assays. Label-free digital holographic microscopy enabled real-time monitoring of morphology, motility, and proliferation. Both compounds induced ROS-mediated cytotoxicity, but responses were notably more pronounced in OECM-1 than in HGEpiC cells. Real-time morphological profiling revealed distinct response patterns: Co primarily exerted cytostatic effects, whereas Cu induced cell shrinkage, impaired motility, and inhibited cell division. The combination treatment (CC) largely reflected Cu-driven morphological and functional changes, with Co coexisting without counteracting Cu’s effects. Taken together, these findings reveal compound-specific mechanisms of action for Cu and Co in OSCC therapy. Full article

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18 pages, 722 KB

Open AccessArticle

Structure–Activity Relationships of Hemocompatible Cationic 6-Azaindole Pyridinium Salts: Antimicrobial and Anticancer Activity

by Roxana Ciorteanu, Ioana C. Marinas, Catalina Ionica Ciobanu, Ionel I. Mangalagiu and Ramona Danac

Molecules 2026, 31(7), 1220; https://doi.org/10.3390/molecules31071220 - 7 Apr 2026

Viewed by 580

Abstract

A series of 6-azaindole pyridinium derivatives were synthesized, structurally characterized, and evaluated for their antimicrobial (against Staphylococcus aureus, Escherichia coli, and Candida albicans) and anticancer properties (against NCI 60 panel). Hemocompatibility was evaluated using the hemolytic index, while ADME properties [...] Read more.

A series of 6-azaindole pyridinium derivatives were synthesized, structurally characterized, and evaluated for their antimicrobial (against Staphylococcus aureus, Escherichia coli, and Candida albicans) and anticancer properties (against NCI 60 panel). Hemocompatibility was evaluated using the hemolytic index, while ADME properties were estimated using in silico methods. Structure–activity relationship analysis indicated that para-substitution of the phenyl ring, particularly with halogen or methoxy groups, influences antimicrobial activity, selectivity toward Gram-positive bacteria, and hemocompatibility. Compounds 2b and 2c showed the most notable antimicrobial effects, including inhibition of microbial adhesion at hemocompatible concentrations. Compound 2b exhibited growth inhibition against cancer cells, showing 57% percent growth inhibition (PGI) against the MDA-MB-468 breast cancer cell line at 10 mM. Overall, these results highlight 6-azaindole pyridinium salts as a promising class of compounds for further investigation. Full article

(This article belongs to the Special Issue Heterocyclic Compounds: Design, Synthesis and Pharmacological Activity)

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16 pages, 615 KB

Open AccessReview

Exploring the Evolving Role of Scopolamine in Pharmacotherapy: From Cognitive Impairment to Neuroplasticity?―A Narrative Review

by Jakub Kukla, Piotr Olejnik and Kaja Kasarełło

Molecules 2026, 31(7), 1219; https://doi.org/10.3390/molecules31071219 - 7 Apr 2026

Viewed by 1444

Abstract

Scopolamine, also known as hyoscine, is a naturally occurring tropane alkaloid derived from plants of the Solanaceae family. Clinically, the compound has long been used for the prevention of motion sickness and postoperative nausea and vomiting, as well as for ophthalmological procedures requiring [...] Read more.

Scopolamine, also known as hyoscine, is a naturally occurring tropane alkaloid derived from plants of the Solanaceae family. Clinically, the compound has long been used for the prevention of motion sickness and postoperative nausea and vomiting, as well as for ophthalmological procedures requiring mydriasis and cycloplegia. However, beyond these established indications, increasing attention has been directed toward its broader neuropharmacological actions. This narrative review aims to summarise current knowledge regarding the pharmacological properties of scopolamine, with particular emphasis on its mechanisms of action and emerging implications in neuroscience and neuropsychiatric disorders. Scopolamine acts as a non-selective antagonist of muscarinic receptor subtypes M1–M5, interfering with cholinergic neurotransmission. Experimental and clinical studies demonstrate that scopolamine induces transient cognitive impairment. This property has led to its widespread use as a pharmacological model of Alzheimer’s disease, enabling investigation of cholinergic contributions to cognitive decline. More recently, several early clinical studies suggested that intravenous administration may produce rapid reductions in depressive symptoms, possibly through modulation of glutamatergic neurotransmission and activation of mTORC1-dependent synaptic plasticity pathways in the prefrontal cortex. Nevertheless, subsequent trials have yielded inconsistent results, and the therapeutic relevance of these findings remains uncertain. Current evidence indicates that scopolamine’s neuropsychiatric effects likely arise from complex interactions between cholinergic, glutamatergic, and neurotrophic signalling systems. Taken together, scopolamine represents both a valuable experimental tool for studying cholinergic function and a mechanistic framework for the development of novel therapeutics targeting rapid neuroplastic processes in neuropsychiatric disorders. Full article

(This article belongs to the Special Issue Phytochemicals as Promising Molecules in Acute and Chronic Neurodegeneration)

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20 pages, 5016 KB

Open AccessArticle

Morphological and Compositional Evolution of Oxidative Coke Deposits Layers Generated by Aviation Kerosene

by Xinyan Pei, Sihan Zou, Keyan Zhang, Zengqi Zhou and Lingyun Hou

Molecules 2026, 31(7), 1218; https://doi.org/10.3390/molecules31071218 - 7 Apr 2026

Viewed by 584

Abstract

Thermal–oxidative coking of aviation fuel remains a critical limitation for fuel-cooled aero-engine systems operating under high heat loads. This study systematically investigates the oxidative coking behavior of RP-3 aviation kerosene, focusing on the coupled evolution of deposit morphology, composition, and operating conditions. Experiments [...] Read more.

Thermal–oxidative coking of aviation fuel remains a critical limitation for fuel-cooled aero-engine systems operating under high heat loads. This study systematically investigates the oxidative coking behavior of RP-3 aviation kerosene, focusing on the coupled evolution of deposit morphology, composition, and operating conditions. Experiments were conducted in an electrically heated stainless-steel tube while independently varying dissolved oxygen concentration, fuel temperature, temperature gradient, operating pressure, and heating duration. Deposit layers were characterized by SEM and XPS, and residual fuel chemistry was analyzed using GC/MS. The results show that dissolved oxygen governs both the extent and mechanism of coking in the autoxidation regime (150–450 °C). Normal and elevated oxygen levels promote autoxidation of straight-chain alkanes, generating oxygen-containing intermediates that form flocculent, oxygen-rich deposits, whereas near-deoxygenated conditions suppress autoxidation but sustain sulfur-dominated, needle-like deposits. Temperature primarily controls deposition rate and morphology, with steep temperature gradients inducing localized coke formation, while pressure exerts only a minor indirect influence. Prolonged operation leads to deposit densification and non-linear accumulation behavior. These findings clarify the links between fuel chemistry, thermal conditions, and deposit architecture, providing a basis for morphology-aware coking models in fuel-cooled aero-engine systems. Full article

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28 pages, 2628 KB

Open AccessArticle

Scalable Jet-O-Mized Eggshell Membrane Processing for Bioactives Promoting Gut Health

by Manar Younes, Tamer A. E. Ahmed, Riadh Hammami and Maxwell T. Hincke

Molecules 2026, 31(7), 1217; https://doi.org/10.3390/molecules31071217 - 7 Apr 2026

Viewed by 763

Abstract

This study introduces a novel, simplified, and scalable two-step process for generating bioactive eggshell membrane (ESM) formulations by combining jet-O-mizer ultra-fine milling of ESM (yielding JEM biomaterial) with KOH-mediated hydrolysis, achieving ~50% solubilization of proteins and peptides and enabling the first evaluation of [...] Read more.

This study introduces a novel, simplified, and scalable two-step process for generating bioactive eggshell membrane (ESM) formulations by combining jet-O-mizer ultra-fine milling of ESM (yielding JEM biomaterial) with KOH-mediated hydrolysis, achieving ~50% solubilization of proteins and peptides and enabling the first evaluation of ESM-derived bioactives for gut health applications. The soluble protein fraction (SJ) was separated from the whole hydrolysate (WJ), and subjected to simulated gastrointestinal digestion to assess stability and bioavailability. The antioxidant capacities of the JEM-derived material showed a significant 15-fold increase compared to soluble non-hydrolyzed JEM (NJEM). SJ inhibited E. coli bacterial growth by 50% within 24 h, compared to the untreated bacterial culture. The formulations demonstrated superior anti-inflammatory properties with lipopolysaccharide (LPS)-induced RAW macrophages, resulting in a 80% reduction in NO production compared to untreated cells. Proteomics analysis of SJ revealed key anti-inflammatory (YBX1, YWHAE) and antimicrobial (OCX36, OC-17, TENP, and histones) effectors whose coordinated activities could modulate gut microbial composition. The permeability of the intestinal barrier model Caco-2 monolayer was not significantly affected by treatment with any JEM-derived formulation, thereby predicting maintenance of intestinal integrity. This study provides safe, novel ESM derivatives with high bioavailability and multifunctional bioactivities, including antibacterial, antioxidant, and anti-inflammatory effects, positioning them as promising candidates for dietary supplements to promote gut health. Full article

(This article belongs to the Special Issue Extraction and Analysis of New Bioactive Compounds Derived from Natural Products, 3rd Edition)

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28 pages, 3145 KB

Open AccessReview

Exploiting Selective Position Labeling to Unveil the Hidden Complexity of Terminomics

by Yuqing Deng, Minghao Li, Peicheng Lu and Bingbing Shi

Molecules 2026, 31(7), 1216; https://doi.org/10.3390/molecules31071216 - 7 Apr 2026

Viewed by 795

Abstract

Selective protein terminal labeling has become essential for system-wide studies of proteolytic mechanisms in disease. These methods enable precise tracking of cleavage dynamics, protease interactions, and cellular networks, offering transformative potential for proteolytic event analysis. This review explores recent advances in N-/C-terminal modification [...] Read more.

Selective protein terminal labeling has become essential for system-wide studies of proteolytic mechanisms in disease. These methods enable precise tracking of cleavage dynamics, protease interactions, and cellular networks, offering transformative potential for proteolytic event analysis. This review explores recent advances in N-/C-terminal modification strategies, specifically for the applications in terminomics—the field focused on protein termini characterization. While protein termini provide valuable insights into functional proteome states, their low abundance in complex samples demands highly selective labeling approaches. We evaluate modern chemical and chemoenzymatic methods that leverage engineered chemical reactivity thresholds or enzymatic precision for site-specific modifications. Emerging strategies show enhanced substrate adaptability, reaction efficiency, and workflow compatibility, enabling broader applications in terminome studies. Full article

(This article belongs to the Collection Chemical Proteomics Research)

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12 pages, 2299 KB

Open AccessArticle

Silicalite-Supported Ni Catalysts for Efficient CO₂ Conversion into CH₄

by Nasir Shezad, Avik De, Ajaikumar Samikannu, Jyri-Pekka Mikkola and Farid Akhtar

Molecules 2026, 31(7), 1215; https://doi.org/10.3390/molecules31071215 - 7 Apr 2026

Viewed by 903

Abstract

The catalytic conversion of CO₂ into methane (CH₄) offers a sustainable solution to the worsening global warming scenario, especially for controlling CO₂ levels. This study reports silicalite-1 supported Ni catalysts with different loadings for CO₂ conversion to CH [...] Read more.

The catalytic conversion of CO₂ into methane (CH₄) offers a sustainable solution to the worsening global warming scenario, especially for controlling CO₂ levels. This study reports silicalite-1 supported Ni catalysts with different loadings for CO₂ conversion to CH₄, prepared via wet impregnation. The X-ray diffraction pattern revealed an increase in crystallite size at higher Ni loadings, which was further supported by N₂ sorption, where the specific surface area and microporosity of the catalysts were decreased. There was a slight shift in the reducibility of the catalysts, potentially indicating the impact of loading on dispersion and spatial distribution. The catalyst performance was evaluated over a range of temperatures at 5 bar and a GHSV of 20,000 mL g_cat⁻¹ h⁻¹. Surprisingly, the Ni(5)@Silicalite-1 exhibited higher CO₂ conversion efficiency across the range of temperatures compared to Ni(10)@Silicalite-1. The NiO(5)@Silicalite-1 demonstrated a maximum CO₂ conversion of 88% at 450 °C, which was approximately 14% higher than that of the catalyst with a 10 wt.% loading. Notably, the CH₄ selectivity pattern was quite identical across the catalysts, underscoring that the reaction pathways were unaffected by the loadings. The higher performance of NiO(5)@Silicalite-1 could be ascribed to smaller NiO crystallites and improved textural properties. Full article

(This article belongs to the Special Issue Design, Synthesis, and Application of Zeolite Materials)

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15 pages, 3990 KB

Open AccessArticle

Influence of Silane Sol Sealing Treatment on the Anti-Corrosion of Micro-Arc Oxidation Coating

by Wei Song, Yasheng Xing, Xueli Xu, Huanxin Li, Weifeng Li, Peng Zhang and Yizhan Li

Molecules 2026, 31(7), 1214; https://doi.org/10.3390/molecules31071214 - 7 Apr 2026

Viewed by 576

Abstract

Silane sol was applied to seal the pores in a micro-arc oxidation coating, with the results proving that the treatment increased the anti-corrosion characteristics of aluminium alloy. Moreover, an electrochemical workstation was employed to test the open-circuit voltage, polarisation potential, and polarisation current [...] Read more.

Silane sol was applied to seal the pores in a micro-arc oxidation coating, with the results proving that the treatment increased the anti-corrosion characteristics of aluminium alloy. Moreover, an electrochemical workstation was employed to test the open-circuit voltage, polarisation potential, and polarisation current of the samples. According to the results, after the aluminium alloy was treated with the micro-arc oxidation coating and underwent subsequent sealing treatment, the open-circuit potential increased from −0.64 to −0.44 V, the corrosion potential from −0.54 to −0.31 V, and the corrosion current density from 56.23 × 10⁻⁷ to 7.76 × 10⁻⁷ A. However, when samples were corroded by 1 mol/L HCl, the corrosion potential and corrosion current density decreased to −0.34 V and 20.42 × 10⁻⁷ A, respectively, proving that sealing the pores on the micro-arc oxidation coating only prevented substrate corrosion for a short time. In addition, slow-strain-rate stretching experiments were conducted to explore the mechanical performances of the samples, determining that the surface treatment had an insignificant effect on the stress of the aluminium alloy but had an important effect on its elongation, and when the surface of the alloy was treated with micro-arc oxidation coating, its elongation decreased from 28% to 26%. Full article

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6 pages, 194 KB

Open AccessEditorial

Heterogeneous Catalysis Is Full of Challenges

by Lin Huang and Yinghuai Zhu

Molecules 2026, 31(7), 1213; https://doi.org/10.3390/molecules31071213 - 7 Apr 2026

Viewed by 726

Abstract

Heterogeneous catalysis is a vibrant branch of chemistry, in that it enables the fast, selective and large-scale production of chemicals [...] Full article

(This article belongs to the Special Issue Research on Heterogeneous Catalysis—2nd Edition)

13 pages, 1990 KB

Open AccessArticle

Study on the Performance of a Novel Microbial-Assisted Chemical Viscosity Reduction Technology for Enhancing Heavy Oil Displacement Efficiency

by Fan Zhang, Qun Zhang, Zhaohui Zhou, Yangnan Shangguan, Wenfeng Song, Yawen Zhou, Huilin Wang, Qianqian Tian, Kang Tang and Lei Liu

Molecules 2026, 31(7), 1212; https://doi.org/10.3390/molecules31071212 - 7 Apr 2026

Viewed by 451

Abstract

High-viscosity reservoirs are widely distributed across various countries with abundant reserves. However, their high resin and asphaltene content leads to elevated oil viscosity and low recovery rates. Conventional chemical flooding techniques are unsuitable for the development of such high-viscosity oilfields. Chemical viscosity reduction [...] Read more.

High-viscosity reservoirs are widely distributed across various countries with abundant reserves. However, their high resin and asphaltene content leads to elevated oil viscosity and low recovery rates. Conventional chemical flooding techniques are unsuitable for the development of such high-viscosity oilfields. Chemical viscosity reduction technologies face challenges such as low viscosity reduction efficiency, poor economic feasibility, and unclear mechanisms. Microbial-assisted chemical viscosity reduction represents a relatively novel approach. This study systematically investigated the enhanced oil recovery performance of a microbial-assisted chemical viscosity reducer. The results demonstrated that this microbial-assisted chemical viscosity reducer achieved a viscosity reduction rate exceeding 85% for five different crude oil samples. It effectively altered the wettability of oil-wet surfaces, improved the oil film stripping rate by 50–65% compared to pure chemical flooding agents, and achieved ultra-low oil–water interfacial tension on the order of 10⁻³ mN/m with crude oil, leading to an enhanced oil recovery (EOR) enhancement of 22–26%. The underlying mechanism is that viscosity-reducing bacteria degrade asphaltene in heavy oil, thereby weakening intermolecular forces. Their metabolites enhance the emulsion stability of the chemical viscosity reduction process. Chemical viscosity reducers enhance the physiological cycle and metabolic activity of microorganisms while also emulsifying and dispersing heavy oil and improving emulsion stability. Therefore, this novel microbial-assisted chemical viscosity reduction technology offers a new and effective EOR method for high-viscosity reservoirs. Full article

(This article belongs to the Topic Functional Materials: Cross-Scale Innovations from Molecular Design to Macroscopic Applications)

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21 pages, 2857 KB

Open AccessReview

Cirsium arvense and Cirsium vulgare: Comparative Ethnopharmacology, Phytochemistry and Pharmacological Review

by Elmira Kartbayeva, Gulnaz Seitimova, Dinara Satmbekova, Meruyert Mukhitdin, Elmira Kabdylkanova and Aliya Kipchakbayeva

Molecules 2026, 31(7), 1211; https://doi.org/10.3390/molecules31071211 - 7 Apr 2026

Cited by 1 | Viewed by 865

Abstract

The genus Cirsium (family Asteraceae, subfamily Carduoideae) comprises more than 200 species distributed throughout the temperate regions of the Northern Hemisphere. In recent years, particular scientific interest has focused on Cirsium arvense (L.) Scop. (creeping thistle) and Cirsium vulgare (Savi) Ten. [...] Read more.

The genus Cirsium (family Asteraceae, subfamily Carduoideae) comprises more than 200 species distributed throughout the temperate regions of the Northern Hemisphere. In recent years, particular scientific interest has focused on Cirsium arvense (L.) Scop. (creeping thistle) and Cirsium vulgare (Savi) Ten. (spear thistle). These species are notable for their high content of secondary metabolites and broad biological activity. However, the available data on their phytochemical composition and biological potential remain fragmented. This information is methodologically diverse and scattered across different scientific disciplines, underscoring the need for systematic analysis. In this study, a comprehensive literature review was conducted. Sources included PubMed, Scopus, Web of Science, Google Scholar, and other online databases. The focus was on phytochemical composition and pharmacological activity. Both species contain a wide range of secondary metabolites. These include phenolic acids (chlorogenic, caffeic, and ferulic acids), flavonoids (luteolin, apigenin, kaempferol, quercetin), triterpenoids (lupeol, taraxerol), and phytosterols. C. vulgare generally has higher levels of chlorogenic acid and flavonoid glycosides. In contrast, C. arvense has a greater abundance of triterpenes and steroidal compounds. Pharmacological studies show antioxidant, antimicrobial, hepatoprotective, anti-inflammatory, and cytotoxic activities for both species. Overall, the available data indicate that C. arvense and C. vulgare are promising sources of biologically active compounds with diverse pharmacological potential. Although there are some limitations regarding standardization and the depth of preclinical and clinical validation, the obtained results confirm their relevance for further pharmacological and phytochemical research. Full article

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18 pages, 1227 KB

Open AccessArticle

Royal Jelly as a Natural Endocrine Modulator of Serum Estradiol Levels in Juvenile Sterlets (Acipenser ruthenus)

by Dragoș Moraru, Ersilia Alexa, Adrian Grozea, Violeta Igna, Sandra Antonia Mihailov, Christine Neagu and Silvia Pătruică

Molecules 2026, 31(7), 1210; https://doi.org/10.3390/molecules31071210 - 6 Apr 2026

Viewed by 731

Abstract

The present study investigates the role of royal jelly as a natural endocrine modulator of serum estradiol levels in juvenile sterlets (Acipenser ruthenus), a species of major interest for sustainable aquaculture. The experiment was conducted over a period of 85 days [...] Read more.

The present study investigates the role of royal jelly as a natural endocrine modulator of serum estradiol levels in juvenile sterlets (Acipenser ruthenus), a species of major interest for sustainable aquaculture. The experiment was conducted over a period of 85 days under controlled recirculating system conditions, using four dietary treatments (n = 30 fish per group): a control group and three groups supplemented with 1%, 3%, and 5% royal jelly. Serum estradiol concentrations were determined by high-performance liquid chromatography (HPLC), while biometric assessment included the determination of total length (L), standard length (Sl), maximum body height (H), body circumference (C), and body mass (BM). Royal jelly supplementation significantly increased serum estradiol levels in a dose-dependent manner (p < 0.05), with the highest values recorded in the 5% group compared to the control. The proportion of individuals with non-detectable estradiol levels decreased progressively with increasing supplementation level. Biometric analysis revealed moderate effects on growth parameters, with no statistically significant differences among groups for most traits (p > 0.05), except for maximum body height, which showed a significant overall effect (ANOVA, p = 0.0089). Principal Component Analysis (PCA) highlighted the relative independence between endocrine variability and growth dynamics. Overall, the findings support the potential of royal jelly as a natural endocrine modulator of serum estradiol, representing a promising and environmentally friendly alternative to synthetic hormonal substances used in aquaculture. This approach may contribute to the development of innovative nutritional strategies for endocrine control and the optimization of biological performance in sturgeons, in accordance with the principles of sustainable aquaculture. Full article

(This article belongs to the Special Issue Applied Chemistry in Europe, 2nd Edition)

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22 pages, 1064 KB

Open AccessReview

Bioprospecting Underutilized Plant By-Products for Antioxidant Natural Extracts: A Review

by Jesús Morales-Jiménez, Rosy G. Cruz-Monterrosa, Monzerrat Rosas Espejel, Ildefonso Guerrero-Encinas, Javier N. González-González, Luis Quihui-Cota, Jorge L. Mejía-Méndez, Alejandra Miranda-Carrazco and José E. Aguilar-Toalá

Molecules 2026, 31(7), 1209; https://doi.org/10.3390/molecules31071209 - 6 Apr 2026

Viewed by 617

Abstract

Underutilized plant by-products are an overlooked source of natural extracts that contain antioxidant bioactive compounds and therapeutic potential. Oxidative stress significantly contributes to the development of various chronic diseases. In this context, natural extracts rich in bioactive compounds derived from underutilized plant by-products [...] Read more.

Underutilized plant by-products are an overlooked source of natural extracts that contain antioxidant bioactive compounds and therapeutic potential. Oxidative stress significantly contributes to the development of various chronic diseases. In this context, natural extracts rich in bioactive compounds derived from underutilized plant by-products emerge as promising options for developing antioxidant-based therapies that target oxidative stress-related molecular pathways involved in the pathogenesis of chronic disease. The valorization of by-products through the recovery of antioxidant-rich extracts is particularly appealing, as non-edible plant parts often contain higher levels of bioactive compounds than their edible counterparts. This review provides a comprehensive overview of antioxidant natural extracts and their major bioactive components, including polyphenols (particularly flavonoids and phenolic acids), terpenoids, alkaloids, and other redox-active compounds. Full article

(This article belongs to the Special Issue Natural Extracts for Pharmaceutical Applications)

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13 pages, 4603 KB

Open AccessArticle

Evidence of Antiproliferative Activity in the Liverwort Isotachis serrulata from Southern Ecuador

by José Miguel Andrade, Ángel Benítez, Aday González-Bakker, Luis Cartuche, José M. Padrón, Ana R. Díaz-Marrero and José J. Fernandez

Molecules 2026, 31(7), 1208; https://doi.org/10.3390/molecules31071208 - 6 Apr 2026

Viewed by 544

Abstract

Natural products from bryophytes represent an underexplored source of structurally diverse bioactive compounds. In this study, extracts of Isotachis serrulata collected in southern Ecuador were evaluated for antiproliferative activity against five human tumor cell lines. Sequential extraction and chromatographic fractionation yielded six fractions, [...] Read more.

Natural products from bryophytes represent an underexplored source of structurally diverse bioactive compounds. In this study, extracts of Isotachis serrulata collected in southern Ecuador were evaluated for antiproliferative activity against five human tumor cell lines. Sequential extraction and chromatographic fractionation yielded six fractions, among which fraction IsF5 displayed the most notable activity, particularly against lung (SW1573) and breast (T-47D) cancer cell lines, with GI₅₀ values within the moderate activity range according to National Cancer Institute criteria. Phytochemical investigation of IsF5 revealed the presence of two glycosylated aromatic constituents, tentatively assigned as tachioside and isotachioside, based on comparative ¹H and ¹³C NMR spectroscopic analysis. These compounds were obtained as a mixture and were not evaluated individually due to limited material. Additionally, species distribution modeling using MaxEnt indicated that I. serrulata is primarily associated with humid montane and páramo ecosystems in the southern, central and northern Andes of Ecuador, where elevation and precipitation variables strongly influence its distribution. This study provides the first integrated assessment of the antiproliferative activity, chemical profiling, and ecological distribution of I. serrulata. Full article

(This article belongs to the Special Issue Biological Evaluation of Plant Extracts, 2nd Edition)

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25 pages, 1253 KB

Open AccessReview

Broadband Coherent Raman Scattering: Excitation Architectures and Operating Regimes

by Roland Ackermann, Timea Koch, Tom Lippoldt, Thomas Gabler and Stefan Nolte

Molecules 2026, 31(7), 1207; https://doi.org/10.3390/molecules31071207 - 6 Apr 2026

Viewed by 830

Abstract

Coherent Raman scattering (CRS) techniques such as coherent anti-Stokes Raman scattering (CARS) provide chemically specific vibrational contrast with signal levels far exceeding spontaneous Raman scattering (SpRS). Extending these to broadband excitation enables multiplex detection across wide spectral regions, including the fingerprint region, CH-stretch [...] Read more.

Coherent Raman scattering (CRS) techniques such as coherent anti-Stokes Raman scattering (CARS) provide chemically specific vibrational contrast with signal levels far exceeding spontaneous Raman scattering (SpRS). Extending these to broadband excitation enables multiplex detection across wide spectral regions, including the fingerprint region, CH-stretch bands and high-frequency vibrational modes. This review provides a structured overview of excitation architecture for broadband CRS, ranging from low-energy oscillator schemes to energy-scalable platforms. The discussion is organized along key design parameters, including spectral bandwidth, excitation intensity, and probe delay, which jointly determine the accessible operating regimes. Rather than representing competing methods, the reviewed architectures are presented as a complementary toolbox for application-driven spectroscopy in chemically reactive environments and complex biological systems. In addition, a representative OPCPA-based implementation is presented as a platform demonstration to illustrate accessible operating regimes, single-shot stability, and multiplex detection capability under realistic experimental conditions. Full article

(This article belongs to the Special Issue Recent Advances in Structural Characterization by Raman Spectroscopy)

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29 pages, 4820 KB

Open AccessReview

From Phytotoxin to Cell-Death Probe: Ophiobolin A and Related Sesterterpenoids in Membrane Stress and Non-Apoptotic Cell Death

by David Aebisher, Izabella Wilk and Dorota Bartusik-Aebisher

Molecules 2026, 31(7), 1206; https://doi.org/10.3390/molecules31071206 - 5 Apr 2026

Viewed by 916

Abstract

Ophiobolin A is a fungal sesterterpenoid initially characterised as a phytotoxin but progressively investigated for its biomedical significance due to its potent and mechanistically characteristic cellular activities. In this review, Ophiobolin A is discussed within the wider landscape of natural products as a [...] Read more.

Ophiobolin A is a fungal sesterterpenoid initially characterised as a phytotoxin but progressively investigated for its biomedical significance due to its potent and mechanistically characteristic cellular activities. In this review, Ophiobolin A is discussed within the wider landscape of natural products as a source of bioactive molecular scaffolds, and current knowledge on its structural features, biosynthesis, chemical synthesis, semi-synthetic modification, and in vitro biological applications is summarised. Evidence drawn from chemical, biochemical, and cell biology studies is integrated to describe the distinctive 5-8-5 tricyclic scaffold, the electrophilic dicarbonyl motif, and their roles in covalent modification of cellular components. Collectively, the reviewed evidence underscores that Ophiobolin A and its derivatives trigger both apoptotic and non-apoptotic cell death pathways. These include paraptosis-like death, which is a regulated form of cell death not associated with apoptosis that is defined by major cytoplasmic vacoulisation. This commonly occurs in apoptosis-resistant cancer models via disruption of membrane lipid homeostasis, calmodulin-dependent signalling, mitochondrial function, and proteostasis. Structure–activity relationship studies show that modulation of electrophilicity, oxidation state, and peripheral functionality enables tuning of potency, selectivity, and traceability while retaining key phenotypes. In addition to anticancer effects, antimicrobial and anti-inflammatory activities are also briefly summarised. Taken together, the literature supports Ophiobolin A as a useful molecular probe for considering cell death mechanisms and as a chemically complex yet suitable starting point for derivative development, while reinforcing the need for improved selectivity, delivery strategies, and in vivo validation to further translational potential. Full article

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28 pages, 4870 KB

Open AccessReview

Recent Advances of Azobenzene-Based Photoresponsive Molecular Switches for Protein-Targeted Photopharmacology

by Jingyu Jiang, Xinrui Yuan and Lei Hu

Molecules 2026, 31(7), 1205; https://doi.org/10.3390/molecules31071205 - 5 Apr 2026

Cited by 1 | Viewed by 1266

Abstract

Azobenzene derivatives constitute a prototypical class of photoresponsive molecular switches with broad utility in synthetic chemistry and biomedical research, owing to their distinctive physicochemical properties. Recent molecular engineering has enabled red-shifted photoisomerization into the visible biological window, thereby enhancing tissue penetration and reducing [...] Read more.

Azobenzene derivatives constitute a prototypical class of photoresponsive molecular switches with broad utility in synthetic chemistry and biomedical research, owing to their distinctive physicochemical properties. Recent molecular engineering has enabled red-shifted photoisomerization into the visible biological window, thereby enhancing tissue penetration and reducing phototoxicity. This review systematically surveys contemporary advances in azobenzene-based photoswitchable systems with a specific focus on medicinal chemistry and photopharmacology. Emphasis is placed on rational design strategies—including ortho-functionalization, heteroaryl substitution, and bridged diazocine scaffolds—that improve photophysical properties, thermal stability, and photostationary state distributions. Particular attention is devoted to the integration of these novel azobenzene motifs as privileged pharmacophores, highlighting their emerging therapeutic applications in neurological modulation, enzyme inhibition, receptor targeting, and oncology, as well as their translational potential in drug discovery and photodynamic therapy. Full article

(This article belongs to the Section Medicinal Chemistry)

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23 pages, 2214 KB

Open AccessReview

Natural Alkaloids as Antimicrobial Agents: Mechanisms, Potentials and Challenges

by Xi-Zhong Zhang, Ming-Xia Chen, Rui Hou, Wan-Qin Wang, Zhen-Dan He, Jie-Shu You and Xun Song

Molecules 2026, 31(7), 1204; https://doi.org/10.3390/molecules31071204 - 5 Apr 2026

Cited by 2 | Viewed by 1691

Abstract

Antimicrobial resistance (AMR) poses a significant global health threat, with multidrug-resistant pathogens undermining the effectiveness of conventional antibiotics. Natural alkaloids, a diverse group of nitrogen-containing compounds mainly derived from plants, are gaining attention as potential antimicrobial agents due to their broad-spectrum activity, structural [...] Read more.

Antimicrobial resistance (AMR) poses a significant global health threat, with multidrug-resistant pathogens undermining the effectiveness of conventional antibiotics. Natural alkaloids, a diverse group of nitrogen-containing compounds mainly derived from plants, are gaining attention as potential antimicrobial agents due to their broad-spectrum activity, structural variety, and unique mechanisms of action. This review examines the antimicrobial properties of natural alkaloids, classifying them by chemical structure (e.g., quinoline, isoquinoline, pyridine, indole, and imidazole alkaloids). Their antibacterial, antifungal, and antiviral activities are discussed, along with the mechanisms by which they target pathogenic microorganisms, including disruption of cell walls and membranes, inhibition of protein synthesis, interference with DNA replication, and viral assembly. The review also explores the synergistic effects of alkaloids when combined with conventional antimicrobial agents. Alkaloids demonstrate potent antimicrobial activity against various pathogens. Quinoline alkaloids, such as quinine, inhibit DNA replication and damage cell membranes. Isoquinoline alkaloids like berberine and sanguinarine exhibit broad-spectrum antibacterial effects. Pyridine alkaloids, including nicotine, disrupt bacterial membranes. In fungi, alkaloids such as sanguinarine and indole derivatives prevent cell wall synthesis and spore germination. Antiviral alkaloids like lycorine target viral RNA polymerases. Additionally, alkaloids enhance the activity of traditional antibiotics by overcoming resistance. Natural alkaloids represent a promising source of antimicrobial agents with diverse mechanisms to combat AMR. Future research should focus on optimizing alkaloid structures, ensuring safety and efficacy, and exploring combination therapies to address the escalating AMR challenge. Full article

(This article belongs to the Special Issue Chemical Structures and Bioactivities of Natural Products Against Inflammation and Cancer)

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15 pages, 1619 KB

Open AccessArticle

Environmentally Friendly Synthesis of Polysubstituted Pyrroles in Ionic Liquid via Gold-Catalyzed Propargylic Substitution/Hydration/Amination/Cycloisomerization Sequence

by Hitomi Chiaki, Yukinori Umezawa, Yoshimitsu Hashimoto and Nobuyoshi Morita

Molecules 2026, 31(7), 1203; https://doi.org/10.3390/molecules31071203 - 5 Apr 2026

Viewed by 511

Abstract

An environmentally friendly synthesis of polysubstituted pyrroles in ionic liquid was achieved via a gold-catalyzed propargylic substitution/hydration/amination/cycloisomerization sequence. Treatment of propargylic alcohols, 1,3-dicarbonyl compounds, and arylamines in the presence of AuBr₃ (5 mol%) and AgOTf (15 mol%) in [EMIM][NTf₂] afforded [...] Read more.

An environmentally friendly synthesis of polysubstituted pyrroles in ionic liquid was achieved via a gold-catalyzed propargylic substitution/hydration/amination/cycloisomerization sequence. Treatment of propargylic alcohols, 1,3-dicarbonyl compounds, and arylamines in the presence of AuBr₃ (5 mol%) and AgOTf (15 mol%) in [EMIM][NTf₂] afforded polysubstituted pyrroles in good to high yield. This reaction involves reacting arylamine with the hydrated propargylic substitution product formed as an intermediate to yield polysubstituted pyrroles. Full article

(This article belongs to the Section Organic Chemistry)

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45 pages, 3419 KB

Open AccessReview

Solvent-Based Extraction Recovers Phytochemicals from Medicinal Plants Demonstrating Anticancer and Chemopreventive Potential: A Review

by Cecile Ojong, Samuel A. Besong and Alberta N. A. Aryee

Molecules 2026, 31(7), 1202; https://doi.org/10.3390/molecules31071202 - 4 Apr 2026

Cited by 3 | Viewed by 1988

Abstract

Cancer remains a leading cause of morbidity and mortality globally, with current therapies often limited by toxicity, drug resistance, and reduced efficacy in advanced stages. Medicinal plants represent important sources of bioactive compounds (BACs) with anticancer and chemopreventive potential; however, their successful application [...] Read more.

Cancer remains a leading cause of morbidity and mortality globally, with current therapies often limited by toxicity, drug resistance, and reduced efficacy in advanced stages. Medicinal plants represent important sources of bioactive compounds (BACs) with anticancer and chemopreventive potential; however, their successful application is strongly influenced by extraction strategies that determine phytochemical recovery and downstream biological activity. This review evaluates solvent-based extraction techniques used to extract BACs from medicinal plants with reported anticancer properties, synthesizing peer-reviewed articles from PubMed and Google Scholar published between 2020 and 2025. Solvent-based methods, including Soxhlet and maceration, were most widely applied due to their operational simplicity and the preservation of structurally diverse metabolites while percolation, decoction, infusion, and hydro-distillation were sparsely utilized. Extraction strategy and solvent polarity emerged as primary factors shaping phytochemical profiles, with phenolics, flavonoids, alkaloids, and terpenoids identified as dominant classes. Reported half maximal inhibitory concentration (IC₅₀) ranged from highly potent (0.12 µg/mL) to weak (30,000 µg/mL), reflecting variability driven by extraction parameters and plant matrix complexity. Anticancer mechanisms commonly involved apoptosis induction, cell-cycle arrest, reactive oxygen species-mediated cytotoxicity, and inhibition of proliferative signaling pathways across breast, cervical, colon, lung, liver, and prostate cancer models. Although solvent-based extraction approaches remain widely used, their context-dependent nature and lack of standardization limit reproducibility. Overall, anticancer and chemotherapeutic efficacy is primarily governed by BAC composition, while extraction methods act as upstream modulators. Future progress requires phytochemical-informed, standardized workflows supported by hybrid extraction systems, AI-assisted optimization, and advanced bioavailability and delivery systems to enable reproducible and clinically relevant translation of plant-derived chemotherapeutics. Full article

(This article belongs to the Special Issue Exploring the Antioxidant Activity of Natural Extracts: New Findings and Potential Food- and Non-Food-Related Applications)

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16 pages, 557 KB

Open AccessReview

Recent Progress in the Regioselective Biotransformation and Multitarget Therapeutic Potential of Ginsenoside Rd

by Xingang Shen, Kun Ming, Hongjiao Shi, Jiawei Li, Ye Yang, Wenping Zhang, Xiuming Cui and Xiaoyan Yang

Molecules 2026, 31(7), 1201; https://doi.org/10.3390/molecules31071201 - 4 Apr 2026

Viewed by 625

Abstract

Ginsenoside Rd, a protopanaxadiol (PPD)-type tetracyclic triterpenoid saponin, has emerged as a promising bioactive constituent for multitarget therapeutic interventions. However, its natural abundance in the source plant is extremely low, making direct extraction both costly and inefficient. This review systematically summarizes the latest [...] Read more.

Ginsenoside Rd, a protopanaxadiol (PPD)-type tetracyclic triterpenoid saponin, has emerged as a promising bioactive constituent for multitarget therapeutic interventions. However, its natural abundance in the source plant is extremely low, making direct extraction both costly and inefficient. This review systematically summarizes the latest research progress on regioselective biotransformation strategies for Rd production since 2022. Furthermore, it comprehensively reviews recent advances in the diverse pharmacological activities of Rd. Beyond its well-recognized neuroprotective effects against neurological disorders including Alzheimer’s disease and Parkinson’s disease, we also highlight its antitumor activity and multitarget protective effects in liver diseases. This review provides a theoretical basis for developing Rd as a high-value nutraceutical and therapeutic candidate for systemic health. Full article

(This article belongs to the Special Issue Natural Products and Their Derivatives with Applications in Health and Diseases)

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16 pages, 1090 KB

Open AccessArticle

Dual-Action Sutures: Chlorhexidine and Dexamethasone for Infection Control and Inflammation Suppression

by Brisa Guadalupe Hernández-Ramírez, Giovanni Palomino-Vizcaino, Lilia Angélica Hurtado-Ayala, Jonathan Vincent Lopez-Baena, Hebrón Vazquez-Estudillo, Arturo Estolano-Cobián, Teresa G. Rodriguez-Tellez, Héctor Milla-Hinojosa, José Manuel Cornejo-Bravo, Kenia Palomino-Vizcaino and Héctor Magaña

Molecules 2026, 31(7), 1200; https://doi.org/10.3390/molecules31071200 - 4 Apr 2026

Viewed by 903

Abstract

Surgical site infections (SSIs) remain a major clinical challenge, particularly due to bacterial adhesion and biofilm formation on suture materials. In this study, we developed a dual drug-eluting suture incorporating chlorhexidine (CHX) and dexamethasone (DEX), with lauric acid used as a binding agent [...] Read more.

Surgical site infections (SSIs) remain a major clinical challenge, particularly due to bacterial adhesion and biofilm formation on suture materials. In this study, we developed a dual drug-eluting suture incorporating chlorhexidine (CHX) and dexamethasone (DEX), with lauric acid used as a binding agent to enhance drug adhesion. The exact composition of the system was CHX/DEX/Lauric Acid, designed to enable localized delivery of both therapeutic agents at the implantation site. Vicryl sutures were dip-coated and characterized by means of FTIR-ATR and HPLC to confirm drug incorporation and release. Mechanical integrity was preserved, with no significant difference in tensile strength between coated and uncoated sutures. Antimicrobial activity was confirmed against Gram-positive and -negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), in addition to the yeast Candida albicans. Cell viability assays demonstrated acceptable biocompatibility, with values exceeding 70%. These findings support the potential of dual-functionalized sutures to reduce SSIs and modulate inflammation, offering a promising strategy for improving postoperative outcomes. Full article

(This article belongs to the Special Issue From Functionalization to Medical Applications of Polymer Materials)

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34 pages, 2111 KB

Open AccessReview

Chemical Compositions, Traditional Applications, and Biological Activities of Gnaphalium affine D. Don: A Comprehensive Review

by Chen Ding, Yimiao Zhou, Lin Yang, Liquan Zhou and Zuowei Xiao

Molecules 2026, 31(7), 1199; https://doi.org/10.3390/molecules31071199 - 4 Apr 2026

Viewed by 874

Abstract

Gnaphalium affine D. Don (G. affine), a genus within the genus Gnaphalium of the Asteraceae family, is recognized as a significant medicinal resource. Phytochemical investigations identified various bioactive compounds in G. affine, including flavonoids, terpenoids, phenolic acids, alkaloids, and amino [...] Read more.

Gnaphalium affine D. Don (G. affine), a genus within the genus Gnaphalium of the Asteraceae family, is recognized as a significant medicinal resource. Phytochemical investigations identified various bioactive compounds in G. affine, including flavonoids, terpenoids, phenolic acids, alkaloids, and amino acids. These compounds exhibit a range of pharmacological activities such as antimicrobial, cough expectorant, antioxidant, and anti-inflammatory properties, as well as the regulation of lipid and glucose metabolism, reduction of uric acid levels, hepatoprotective effects, and anti-tumor activities. However, research concerning the chemical composition, biological activities, and potential applications of synthesized G. affine remains limited. In light of the growing interest in this species, the present paper aims to provide a comprehensive overview of the current research advancements related to the traditional applications, chemical constituents, and biological effects of G. affine. Additionally, this study will discuss future prospects for the development and application of G. affine to enhance its utilization in various fields. Full article

(This article belongs to the Special Issue Plant-Based Food Science: Chemical Composition and Biological Activity—2nd Edition)

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21 pages, 501 KB

Open AccessArticle

Enrichment of Wheat–Chia Bread with Hemp, and Buckwheat Flours and Cistus incanus L. Infusion: Impact on Chemical Composition, Polyphenols, Fatty Acids, Amino Acids, and Consumer Acceptance

by Anna Mikulec, Barbara Mickowska, Joanna Oracz, Kaja Karwowska, Magdalena Skotnicka and Stanisław Kowalski

Molecules 2026, 31(7), 1198; https://doi.org/10.3390/molecules31071198 - 3 Apr 2026

Viewed by 696

Abstract

This study aimed to assess whether hemp or buckwheat flour, and the replacement of water with cistus infusion, can simultaneously improve the nutritional value and antioxidant potential of wheat–chia bread while maintaining acceptable sensory quality. Control bread (WCh) and variants with hemp flour [...] Read more.

This study aimed to assess whether hemp or buckwheat flour, and the replacement of water with cistus infusion, can simultaneously improve the nutritional value and antioxidant potential of wheat–chia bread while maintaining acceptable sensory quality. Control bread (WCh) and variants with hemp flour (WChH) or buckwheat flour (WChB), prepared with either water or cistus infusion (Cis), were baked. The chemical composition, amino acid profile and protein quality (AAS), fatty acid profile, phenolic compounds and antioxidant properties (TPC, FRAP), color (CIELAB), and texture were determined. E-tongue and e-nose analyses, as well as consumer evaluation, were also performed. Hemp flour most significantly increased the protein and dietary fiber content of bread and improved the PUFA content and PUFA/SFA ratio. Buckwheat flour shifted the lipid profile toward MUFA and yielded the highest lysine AAS, although lysine remained the limiting amino acid in all variants. Cistus infusion increased the polyphenol pool and antioxidant activity, with the strongest effect observed in the combined WChH/Cis and WChB/Cis systems. Electronic nose and an electronic tongue analyses confirmed significant differentiation of the flavor and aroma profiles among variants. Consumer evaluation showed a decrease in acceptance following hemp flour addition, which was partially mitigated by cistus infusion, while buckwheat variants maintained good sensory acceptance. Full article

(This article belongs to the Special Issue Molecular, Technological and Nutritional Aspects of Food Fortification and Processing)

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