Molecules

32 pages, 2628 KiB

Open AccessFeature PaperReview

Flavonoids and Other Polyphenols: Bioactive Molecules from Traditional Medicine Recipes/Medicinal Plants and Their Potential for Phytopharmaceutical and Medical Application

by Aekkhaluck Intharuksa, Sompop Kuljarusnont, Yohei Sasaki and Duangjai Tungmunnithum

Molecules 2024, 29(23), 5760; https://doi.org/10.3390/molecules29235760 - 5 Dec 2024

Abstract

Currently, natural bioactive ingredients and/or raw materials are of significant interest to scientists around the world. Flavonoids and other polyphenols are a major group of phytochemicals that have been researched and noted as bioactive molecules. They offer several pharmacological and medical benefits. This [...] Read more.

Currently, natural bioactive ingredients and/or raw materials are of significant interest to scientists around the world. Flavonoids and other polyphenols are a major group of phytochemicals that have been researched and noted as bioactive molecules. They offer several pharmacological and medical benefits. This current review aims to (1) illustrate their benefits for human health, such as antioxidant, anti-aging, anti-cancer, anti-inflammatory, anti-microbial, cardioprotective, neuroprotective, and UV-protective effects, and also (2) to perform a quality evaluation of traditional medicines for future application. Consequently, keywords were searched on Scopus, Google Scholar, and PubMed so as to search for related publications. Then, those publications were carefully checked in order to find current and non-redundant studies that matched the objective of this review. According to this review, researchers worldwide are very interested in discovering the potential of flavonoids and other polyphenols, used in traditional medicines and taken from medicinal plants, in relation to medical and pharmaceutical applications. Many studies focus on the health benefits of flavonoids and other polyphenols have been tested using in silico, in vitro, and in vivo models. However, few studies have been carried out using clinical trials that have trustworthy subject sizes and are in accordance with clinical practice guidelines. Additionally, interesting research directions and perspectives for future studies are highlighted in this work. Full article

(This article belongs to the Special Issue Flavonoids’ and Other Polyphenols’ Pharmacological Activities for Phytopharmaceutical and Medicinal Applications, 2nd Edition)

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18 pages, 11235 KiB

Open AccessArticle

Preparation and Evaluation of a Combination of Chelating Agents for the Removal of Inhaled Uranium

by Lintao Li, Runtian Li, Ruohan Guo, Shuang Guo, Xuan Qiao, Xinru Wu, Peng Han, Yunbo Sun, Xiaoxia Zhu, Zhuona Wu, Hui Gan, Zhiyun Meng, Guifang Dou, Ruolan Gu and Shuchen Liu

Molecules 2024, 29(23), 5759; https://doi.org/10.3390/molecules29235759 - 5 Dec 2024

Abstract

Inhalation of aerosolized uranium is recognized as a principal mode of exposure, posing significant risks of damage to the lungs, kidneys, and other vital organs. To enhance nuclide elimination from the body, chelating agents are employed; however, single-component chelators often exhibit limited spectral [...] Read more.

Inhalation of aerosolized uranium is recognized as a principal mode of exposure, posing significant risks of damage to the lungs, kidneys, and other vital organs. To enhance nuclide elimination from the body, chelating agents are employed; however, single-component chelators often exhibit limited spectral activity and low effectiveness, resulting in toxicologically relevant concentrations. We have developed a composite chelating agent composed of 3,4,3-Li(1,2-HOPO), DFP, and HEDP in optimized ratios, demonstrating marked improvements in eliminating inhaled uranium. The selection of these components was initially guided by an agarose gel dynamics method, focusing on uranium binding and removal efficacy. Optimization of the formula was conducted through response surface methodology in a cellular model. The compound’s ability to enhance survival rates in mice subjected to acute uranium inhalation was confirmed, showing a dose-dependent improvement in survival in severely affected mice. Comparative assessments indicated that this multifaceted chelating agent substantially surpasses the uranium tissue clearance achieved by individual chelating agents. Full article

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19 pages, 1182 KiB

Open AccessArticle

Synthesis, Characterization and Catalytic/Antimicrobial Activities of Some Transition Metal Complexes Derived from 2-Floro-N-((2-Hydroxyphenyl)Methylene)Benzohydrazide

by Ahmed K. Hijazi, Ziyad A. Taha, Dua’a K. Issa, Heba M. Alshare, Waleed M. Al-Momani, Ali Elrashidi and Ahmad S. Barham

Molecules 2024, 29(23), 5758; https://doi.org/10.3390/molecules29235758 - 5 Dec 2024

Abstract

Background: In the last few decades, the field of coordination chemistry has grown very fast, especially in the fields of pharmaceutical, biological and catalytic studies. In ancient times, metals were thought to be beneficial to health issues but nowadays the link between organic–metal [...] Read more.

Background: In the last few decades, the field of coordination chemistry has grown very fast, especially in the fields of pharmaceutical, biological and catalytic studies. In ancient times, metals were thought to be beneficial to health issues but nowadays the link between organic–metal substances and different industrial and medicinal properties is well established. Methods: A Schiff base ligand (2-fluoro-N’-[(E)-2-hydroxyphenyl) methylene] benzohydrazide) was reacted with a series of transition metals to produce complexes with a general formula [ML₂(NO₃)]NO₃.nH₂O, where [M = Zn, Cu, Co, Ni, Mn], and [n = 0, 1], corresponding to complexes 1–5. The nature of the bond was determined in the solid state and solution using spectral studies (¹H-NMR, ¹³C-NMR, UV-Vis and FT-IR), TGA, EPR, elemental analysis and molar conductivity measurement. Results: All M(II) complexes are 1:1 electrolytes, as illustrated by their molar conductivities. The results demonstrate that all synthesized complexes present a coordination number of six by the bonding of the bidentate ligand via its azomethine nitrogen atoms and carbonyl oxygen atoms, as well as with one nitrate group as a bidentate ligand via two oxygen atoms. The DPPH radical scavenging technique was used to investigate the antioxidant activities of the ligand [L] and the metal complexes. It is clear that the activity increased in M (II) complexes compared to the Schiff base ligand. Complex 5 showed the highest activity, with an excellent activity of 90.4%, while complex 4 showed the lowest. The antibacterial activities of the Schiff base and its complexes have been examined against various pathogenic bacteria to measure their inhibition potential. Complex 2 showed remarkable activity against Gram (+) bacteria and fungi with an MIC value of 8 μg/mL, which is greater than that of the positive controls, oxytetracycline and fluconazole. The catalytic activities of all complexes were examined in the oxidation of aniline, and the results illustrated that all complexes had a 100% selectivity in producing only azobenzene, and complex 4 had the highest activity (91%). Conclusion: The obtained results from this study show that the antioxidant and antibacterial properties of both the Schiff base ligand and its derived complexes are promising, with some demonstrating remarkable activities. Moreover, the catalytic activities and selectivities of the prepared complexes in aniline oxidation are interesting. Full article

(This article belongs to the Special Issue Recent Advance in Transition Metal Complexes and Their Applications II)

17 pages, 1401 KiB

Open AccessArticle

Synthesis and Characterisation of Phosphino-Aryloxide Rare Earth Complexes

by Elias Alexopoulos, Yu Liu, Alex W. J. Bowles, Benjamin L. L. Réant and Fabrizio Ortu

Molecules 2024, 29(23), 5757; https://doi.org/10.3390/molecules29235757 - 5 Dec 2024

Abstract

A series of homoleptic rare earth (RE) complexes bearing phosphino-aryloxide ligands (1-RE, 2-La) has been prepared. The complexes have been characterised using multinuclear NMR and IR spectroscopy, X-ray crystallography and elemental analysis. Structural characterisation highlighted the different RE–P interactions as [...] Read more.

A series of homoleptic rare earth (RE) complexes bearing phosphino-aryloxide ligands (1-RE, 2-La) has been prepared. The complexes have been characterised using multinuclear NMR and IR spectroscopy, X-ray crystallography and elemental analysis. Structural characterisation highlighted the different RE–P interactions as a result of differing Lewis acidity and ionic size across the series, hinting at the possibility of FLP-type activity. The potential reactivity of these complexes has been tested by reacting them with small molecules (H₂, CO, CO₂). A series of side-products (3-RE) has also been observed, isolated and characterised, featuring the incorporation of a phosphonium-aryloxide ligand. Full article

(This article belongs to the Special Issue Exclusive Feature Papers in Inorganic Chemistry, 2nd Edition)

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15 pages, 2355 KiB

Open AccessArticle

Doubly Metathetic NiCl₂-Catalyzed Coupling Between Bis(2-oxazolines) and Aldehydes: A Novel Access to Bis(ester-imine) Derivatives

by Sara Colombo, Julie Oble, Giovanni Poli, Leonardo Lo Presti, Giovanni Macetti, Alessandro Contini, Gianluigi Broggini, Marta Papis and Camilla Loro

Molecules 2024, 29(23), 5756; https://doi.org/10.3390/molecules29235756 - 5 Dec 2024

Abstract

The coupling between bis(2-oxazolines) and two equivalents of aromatic aldehydes in the presence of catalytic amounts of NiCl₂ affords an ester-imine product in synthetically useful yields. This virtually unknown, 100% atom-economic transformation involves the formal metathesis between the C=N double bond of [...] Read more.

The coupling between bis(2-oxazolines) and two equivalents of aromatic aldehydes in the presence of catalytic amounts of NiCl₂ affords an ester-imine product in synthetically useful yields. This virtually unknown, 100% atom-economic transformation involves the formal metathesis between the C=N double bond of the bis(2-oxazoline) moiety, which undergoes ring-opening, and the C=O double bond of the aldehyde. The scope of this transformation is studied, and a mechanism is proposed based on DFT calculations. Full article

(This article belongs to the Special Issue Featured Papers in Organometallic Chemistry—2nd Edition)

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18 pages, 1096 KiB

Open AccessArticle

Quercetin and Mesenchymal Stem Cell Metabolism: A Comparative Analysis of Young and Senescent States

by Alexandra Ivan, Alexandra Teodora Lukinich-Gruia, Iustina-Mirabela Cristea, Maria-Alexandra Pricop, Crenguta Livia Calma, Alina-Georgiana Simina, Călin Adrian Tatu, Atena Găluscan and Virgil Păunescu

Molecules 2024, 29(23), 5755; https://doi.org/10.3390/molecules29235755 - 5 Dec 2024

Abstract

Quercetin is a natural flavonoid renowned for its potent antioxidant, anti-inflammatory, anti-diabetic, and antibacterial properties, making it a highly promising candidate for the treatment of various medical conditions. Our current study investigates the influence of quercetin on energy metabolism, fatty acid composition, oxidative [...] Read more.

Quercetin is a natural flavonoid renowned for its potent antioxidant, anti-inflammatory, anti-diabetic, and antibacterial properties, making it a highly promising candidate for the treatment of various medical conditions. Our current study investigates the influence of quercetin on energy metabolism, fatty acid composition, oxidative stress gene expression, and sirtuin expression in early- and late-stage passages of stem cells derived from human exfoliated deciduous teeth (SHEDs). Mitochondrial respiration was analyzed by measuring oxygen consumption following a 24 h quercetin treatment, while fatty acid profiles were examined using gas chromatography–mass spectrometry (GC-MS). Additionally, quantitative PCR (qPCR) was used to assess the expression of oxidative stress genes and sirtuins. In younger SHEDs, quercetin enhances metabolic activity and mitochondrial respiration, although higher doses may decrease mitochondrial activity. Conversely, in older, senescent SHEDs, quercetin supports mitochondrial function at lower concentrations but appears to inhibit respiration at higher doses. These results suggest that quercetin may hold therapeutic potential for maintaining SHED viability and function, especially at lower doses in older cells. Further research is essential to fully elucidate a dose-dependent effect of quercetin and optimize its applications in regenerative medicine. Full article

(This article belongs to the Special Issue Unveiling the Applications of Bioactive Compounds in Functional Foods for Optimal Human Health)

17 pages, 2867 KiB

Open AccessArticle

Phytochemical Profile and Biological Activity of the Ethanol Extracts from the Aerial Parts of Adonis tianschanica (Adolf.) Lipsch. Growing in Kazakhstan

by Saule Orynbekova, Wirginia Kukula-Koch, Zuriyadda Sakipova, Bashaer Alsharif, Beibhinn Rafferty, Talgat Nurgozhin, Zoya Allambergenova, Piotr Dreher, Kazimierz Głowniak and Fabio Boylan

Molecules 2024, 29(23), 5754; https://doi.org/10.3390/molecules29235754 - 5 Dec 2024

Abstract

Adonis tianschanica is a lesser-known plant species belonging to the genus Adonis that grows in Kazakhstan. The aim of this study was to characterize the composition of the ethanolic, water, and hydroethanolic extracts from the aerial parts of A. tianschanica by HPLC-ESI-QTOF-MS/MS to [...] Read more.

Adonis tianschanica is a lesser-known plant species belonging to the genus Adonis that grows in Kazakhstan. The aim of this study was to characterize the composition of the ethanolic, water, and hydroethanolic extracts from the aerial parts of A. tianschanica by HPLC-ESI-QTOF-MS/MS to isolate the major compound isoquercitrin by HSCCC (High-Speed Counter-Current Chromatography) and to determine the cytotoxicity and anti-inflammatory potential of the extracts produced with this plant. Fingerprinting of the analyzed extracts showed the presence of a multitude of metabolites comprising polyphenols, organic acids, and coumarins, and only trace quantities of cardiac glycosides in the analyzed samples. Flavonoids were certainly the best-represented group, with kaempferol, quercetin, and their derivatives as the major components of the extracts. Key findings in this paper were that the ethanol: water (50:50 v/v) extract of A. tianschanica and its major compound isoquercitrin were able to reduce the production of NO induced by LPS, in addition to demonstrating anti-inflammatory effects by reducing cytokines such as IL-6, TNF-α, and IL-1β. Full article

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18 pages, 3493 KiB

Open AccessArticle

The Formation of γ-Valerolactone from Renewable Levulinic Acid over Ni-Cu Fly Ash Zeolite Catalysts

by Margarita Popova, Silviya Boycheva, Ivan Dimitrov, Momtchil Dimitrov, Daniela Kovacheva, Daniela Karashanova, Nikolay Velinov, Genoveva Atanasova and Agnes Szegedi

Molecules 2024, 29(23), 5753; https://doi.org/10.3390/molecules29235753 - 5 Dec 2024

Abstract

Zeolites with different structures (P1, sodalite, and X) were synthesized from coal fly ash by applying ultrasonically assisted hydrothermal and fusion–hydrothermal synthesis. Bimetallic catalysts, containing 5 wt.% Ni and 2.5 wt.% Cu, supported on the zeolites, were prepared by a post-synthesis incipient wetness [...] Read more.

Zeolites with different structures (P1, sodalite, and X) were synthesized from coal fly ash by applying ultrasonically assisted hydrothermal and fusion–hydrothermal synthesis. Bimetallic catalysts, containing 5 wt.% Ni and 2.5 wt.% Cu, supported on the zeolites, were prepared by a post-synthesis incipient wetness impregnation method. The catalysts were characterized by X-ray powder diffraction (XRPD), N₂ physisorption, transmission electron microscopy (TEM), Mössbauer and X-ray photoelectron spectroscopies (XPS), and H₂–temperature-programmed reduction (H₂-TPR) analyses. The XRPD results showed that crystalline Cu⁰ and Ni_xCu_y intermetallic nanoparticles were formed in the reduced catalysts. The presence of the intermetallic phase affected the reducibility of the nickel by shifting it to a lower temperature, as confirmed by the H₂-TPR curves. Based on the Mössbauer spectroscopic results, it was established that the iron contamination of the coal fly ash zeolites (CFAZs) was distributed in ionic positions of the zeolite lattice and as a finely dispersed iron oxide phase on the external surface of the supports. The formation of the NiFe alloy, not detectable by XRPD, was also evidenced on the impregnated samples. The catalysts were studied in the upgrading of levulinic acid (LA), derived from lignocellulosic biomass, to γ-valerolactone (GVL), in a batch reactor under 30 bar H₂ pressure at 150 and 200 °C, applying water as a solvent. The NiCu/SOD and NiCu/X catalysts showed total LA conversion and a high GVL yield (>75%) at a reaction temperature of 200 °C. It was found that the textural parameters of the catalysts have less influence on the catalytic activity, but rather the stable dispersion of metals during the reaction. The characterization of the spent catalyst found the rearrangement of the support structure. The high LA conversion and GVL yield can be attributed to the weak acidic character of the support and the moderate hydrogenation activity of the Ni-Cu sites with high dispersion. Full article

(This article belongs to the Section Materials Chemistry)

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13 pages, 3698 KiB

Open AccessArticle

Visible-Light-Induced Photocatalytic Degradation of Naproxen Using 5% Cu/TiO₂, Transformation Products, and Mechanistic Studies

by Sarah Ahmed Hasan, Abbas Khaleel, Soleiman Hisaindee and Mohammed A. Meetani

Molecules 2024, 29(23), 5752; https://doi.org/10.3390/molecules29235752 - 5 Dec 2024

Abstract

The presence of drugs in wastewater effluent is of concern due to their effects on the aquatic fauna and flora and there are growing efforts for their removal from the environment. In this paper, we study the photocatalytic visible-light degradation of naproxen, an [...] Read more.

The presence of drugs in wastewater effluent is of concern due to their effects on the aquatic fauna and flora and there are growing efforts for their removal from the environment. In this paper, we study the photocatalytic visible-light degradation of naproxen, an over-the-counter anti-inflammatory drug, using 5% copper-doped TiO₂. The photocatalyst was characterized by XRD and BET surface area measurements. The optimal conditions for the degradation of 1 × 10⁻³ M of naproxen were found to be 3 h, with a catalyst loading of 50 mg/100 mL of the drug solution, and an acidic pH of 4.55. The degradation followed pseudo-first order kinetics and achieved a photodegradation efficiency of 44.8%. HPLC was used to separate the degradation products and their structures were determined using MS/MS data. A pathway for the degradation of naproxen is proposed along with degradation mechanisms. The major degradation events involve the formation of hydroxyl radicals, hydroxylation, keto-enol tautomerism, and decarboxylation. Full article

(This article belongs to the Special Issue Advanced Photocatalytic Materials for Energy Conversion and Environmental Remediation)

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10 pages, 1275 KiB

Open AccessArticle

Ab Initio Study of the β-Fe₂O₃ Phase

by Priyanka Mishra and Carmine Autieri

Molecules 2024, 29(23), 5751; https://doi.org/10.3390/molecules29235751 - 5 Dec 2024

Abstract

We present first-principles results on the electronic and magnetic properties of the cubic bulk

β

-phase of

{Fe}_{2} O_{3}

. Given that all Fe–Fe magnetic couplings are expected to be antiferromagnetic within this high-symmetry crystal structure, the system may exhibit some [...] Read more.

We present first-principles results on the electronic and magnetic properties of the cubic bulk

β

-phase of

{Fe}_{2} O_{3}

. Given that all Fe–Fe magnetic couplings are expected to be antiferromagnetic within this high-symmetry crystal structure, the system may exhibit some signature of magnetic frustration, making it challenging to identify its magnetic ground state. We have analyzed the possible magnetic phases of the

β

-phase, among which there are ferrimagnets, altermagnets, and Kramers antiferromagnets. While the

α

-phase is an altermagnet and the

γ

-phase is a ferrimagnet, we conclude that the magnetic ground state for the bulk

β

-phase of

{Fe}_{2} O_{3}

is a Kramers antiferromagnet. Moreover, we find that close in energy, there is a bulk d-wave altermagnetic phase. We report the density of states and the evolution band gap as a function of the electronic correlations. For suitable values of the Coulomb repulsion, the system is a charge-transfer insulator with an indirect band gap of 1.5 eV. More in detail, the unit cell of the

β

-phase is composed of

8 {Fe}_{a}

atoms and

24 {Fe}_{b}

atoms. The

8 {Fe}_{a}

atoms lie on the corner of a cube, and their magnetic ground state is a G-type. This structural phase is composed of zig-zag chains

{Fe}_{a} ‐ {Fe}_{b} ‐ {Fe}_{a} ‐ {Fe}_{b}

with spin configuration ↑-↑-↓-↓ along the 3 directions such that for every

{Fe}_{a}

atoms there are

3 {Fe}_{b}

atoms. As the opposite to the

γ

-phase, the magnetic configuration between the first neighbor of the same kind is always antiferromagnetic while the magnetic configuration between

{Fe}_{a}

and

{Fe}_{b}

is ferro or antiferro. In this magnetic arrangement, first-neighbor interactions cancel out in the mean-field estimation of the Néel temperature, leaving second-neighbor magnetic exchanges as the primary contributors, resulting in a Néel temperature lower than that of other phases. Our work paves the way toward the ab initio study of nanoparticles and alloys for the

β

-phase of

{Fe}_{2} O_{3}

. Full article

(This article belongs to the Special Issue Density Functional Theory in the Age of Chemical Intelligence, 2nd Edition)

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14 pages, 2014 KiB

Open AccessArticle

Using Static Multiple Light Scattering to Develop Microplastic-Free Seed Film-Coating Formulations

by Rozenn Langlet, Romain Valentin, Marie Morard and Christine Delgado Raynaud

Molecules 2024, 29(23), 5750; https://doi.org/10.3390/molecules29235750 - 5 Dec 2024

Abstract

Seed film-coatings used for seed treatment often contain microplastics which must be replaced. The objective of this study is to analyze the influence of substitutes (maltodextrin, waxy maize glucose syrup (WMGS), methylcellulose, tragacanth gum (TG), arabic gum (AG), polyvinyl alcohol (PVA), ethoxylated rapeseed [...] Read more.

Seed film-coatings used for seed treatment often contain microplastics which must be replaced. The objective of this study is to analyze the influence of substitutes (maltodextrin, waxy maize glucose syrup (WMGS), methylcellulose, tragacanth gum (TG), arabic gum (AG), polyvinyl alcohol (PVA), ethoxylated rapeseed oil (ERO)), and xanthan gum as a thickener on the stability of a seed film-coating via Static Multiple Light Scattering (SMLS) technology. The results demonstrate that the incorporation of each polymer results in an increase in the quantity of particles migrating from the supernatant phase, but a concomitant decrease in their sedimentation rate and in the thickness of the supernatant phase (e_c). Furthermore, the redispersion capacity (C_d) of the particles in the seed film-coating is also decreased after the introduction of each polymer, potentially due to their adsorption to the particles. The impact of the thickener is contingent upon the specific polymer employed. Its incorporation reduces the number of particles migrating from the supernatant phase and their sedimentation rate for all of the polymers studied except AG and ERO. However, it reduces e_c for all seed film-coatings. Depending on the substitutes, thickener incorporation either improves (WMGS, maltodextrin, AG) or deteriorates (TG, PVA, ERO) C_d. The formulation containing tragacanth gum shows a redispersing capacity with C_d ≤ 1. This study introduces a novel analytical criterion, the redispersion capacity C_d, which can be employed to characterize dispersed systems. Full article

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14 pages, 713 KiB

Open AccessArticle

Chemical Profile and Biological Properties of Methanolic and Ethanolic Extracts from the Aerial Parts of Inula britannica L. Growing in Central Asia

by Aktolkyn K. Ibadullayeva, Martyna Kasela, Kaldanay K. Kozhanova, Gulnara M. Kadyrbayeva, Jarosław Widelski, Krzysztof Wojtanowski, Aleksandra Józefczyk, Katarzyna Suśniak, Piotr Okińczyc, Meruyert I. Tleubayeva, Aigerim A. Karaubayeva, Moldir A. Zhandabayeva, Aigerim Z. Mukhamedsadykova and Anna Malm

Molecules 2024, 29(23), 5749; https://doi.org/10.3390/molecules29235749 - 5 Dec 2024

Abstract

The genus Inula has been used in folk medicine for centuries; however, the data concerning Inula britannica L. are scarce. This study aimed at investigating the chemical composition of methanolic and ethanolic extracts from the aerial parts of I. britannica collected in Kazakhstan [...] Read more.

The genus Inula has been used in folk medicine for centuries; however, the data concerning Inula britannica L. are scarce. This study aimed at investigating the chemical composition of methanolic and ethanolic extracts from the aerial parts of I. britannica collected in Kazakhstan and evaluating their antimicrobial and antioxidant properties, with special attention being paid to polyphenols. The total content of polyphenols and flavonoids in the extracts was determined colorimetrically, while their qualitative and quantitative analyses were conducted using HPLC/ESI-QTOF-MS and RP-HPLC/DAD. Their antioxidant potential was determined using the FRAP and DPPH methods, whereas their antimicrobial activity was determined by the microdilution method towards a panel of reference microorganisms, including pathogens of the human gastrointestinal tract. Chemical analysis demonstrated that the methanolic extract had a higher content of polyphenols (58.02 vs. 43.44 mg GAE/g) and flavonoids (21.69 vs. 13.91 mg QUE/g) than the ethanolic extract. In both extracts, 15 compounds were identified, with the highest contents being those of cynarine (13.96 and 11.68 mg/g) and chlorogenic acid (9.22 and 5.09 mg/g). The DPPH assay showed a higher antioxidant activity of the methanolic extract (19.78 ± 0.12 mg GAE/g) in comparison to that of the ethanolic extract (15.56 ± 0.24 mg GAE/g). Similarly, the FRAP method showed that the methanolic extract exerted a much higher antioxidant activity (5.07 ± 0.18 mmol Fe²⁺/g) than the ethanolic extract (0.39 ± 0.01 mmol Fe²⁺/g). In contrast, both extracts showed similar antimicrobial properties, with the highest activity being that against Helicobacter pylori ATCC 43504 (MIC = 0.125–0.25 mg/mL). This paper presents novel data on I. britannica L., implying its significance as a source of valuable active compounds and being a prerequisite for further biological studies. Full article

(This article belongs to the Special Issue Biological Activity of Plant Extracts)

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16 pages, 2432 KiB

Open AccessReview

Perspectives on Applications of ¹⁹F-NMR in Fragment-Based Drug Discovery

by Qingxin Li and CongBao Kang

Molecules 2024, 29(23), 5748; https://doi.org/10.3390/molecules29235748 - 5 Dec 2024

Abstract

Fragment-based drug discovery is a powerful approach in drug discovery, applicable to a wide range of targets. This method enables the discovery of potent compounds that can modulate target functions, starting from fragment compounds that bind weakly to the targets. While biochemical, biophysical, [...] Read more.

Fragment-based drug discovery is a powerful approach in drug discovery, applicable to a wide range of targets. This method enables the discovery of potent compounds that can modulate target functions, starting from fragment compounds that bind weakly to the targets. While biochemical, biophysical, and cell-based assays are commonly used to identify fragments, ¹⁹F-NMR spectroscopy has emerged as a powerful tool for exploring interactions between biomolecules and ligands. Because fluorine atoms are not naturally present in biological systems, ¹⁹F-NMR serves as a sensitive method for fragment screening against diverse targets. Herein, we reviewed the applications of ¹⁹F-NMR in fragment screening, highlighting its effectiveness in identifying fragments that bind weakly to various targets such as proteins and RNA. The accumulated evidence suggests that ¹⁹F-NMR will continue to be a crucial tool in drug discovery. Full article

(This article belongs to the Special Issue Application of Spectroscopy for Drugs)

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15 pages, 12868 KiB

Open AccessArticle

Bithiophene-Based Donor–π–Acceptor Compounds Exhibiting Aggregation-Induced Emission as Agents to Detect Hidden Fingerprints and Electrochromic Materials

by Patrycja Filipek, Magdalena Kałkus, Agata Szlapa-Kula and Michał Filapek

Molecules 2024, 29(23), 5747; https://doi.org/10.3390/molecules29235747 - 5 Dec 2024

Abstract

A group of bithiophenyl compounds comprising the cyanoacrylate moiety were designed and successfully synthesized. The optical, (spectro)electrochemical, and aggregation-induced emission properties were studied. DFT calculations were used to explain the reaction’s regioselectivity and to determine the molecules’ energy parameters (i.e., band gaps, HOMO [...] Read more.

A group of bithiophenyl compounds comprising the cyanoacrylate moiety were designed and successfully synthesized. The optical, (spectro)electrochemical, and aggregation-induced emission properties were studied. DFT calculations were used to explain the reaction’s regioselectivity and to determine the molecules’ energy parameters (i.e., band gaps, HOMO levels, and LUMO levels). The aggregation-induced emission of compounds has been studied in the mixture of DMF (as a good solvent) and water (as a poor solvent), with different water fractions ranging from 0% to 99%. It has been shown that there are differences in the physicochemical properties of the obtained compounds due to the length of the alkyl chain in the ester group. Investigated derivatives were tested for their potential use in visualizing latent fingerprints and electrochromic materials. Full article

(This article belongs to the Section Photochemistry)

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13 pages, 3388 KiB

Open AccessArticle

Cytotoxic and Antibacterial Cyclodepsipeptides from an Endophytic Fungus Fusarium avenaceum W8

by Zimo Wang, Bo Liu, Yanlei Wang, Yicen Xu, Hai Ma and Yi Sun

Molecules 2024, 29(23), 5746; https://doi.org/10.3390/molecules29235746 - 5 Dec 2024

Abstract

Seven cyclic depsipeptides, including two new cyclic pentadepsipeptides avenamides A (1) and B (2), were isolated from a plant-derived fungus Fusarium avenaceum W8 by using the bioassay-guided fractionation method. The planar structures were elucidated by using comprehensive spectroscopic analyses, [...] Read more.

Seven cyclic depsipeptides, including two new cyclic pentadepsipeptides avenamides A (1) and B (2), were isolated from a plant-derived fungus Fusarium avenaceum W8 by using the bioassay-guided fractionation method. The planar structures were elucidated by using comprehensive spectroscopic analyses, including 1D and 2D NMR, as well as MS/MS spectrometry. The absolute configuration of the amino acid and hydroxy acid residues was confirmed by using the advanced Marfey’s method and chiral HPLC analysis, respectively. Compounds 1–7 were evaluated for their cytotoxic activities against A549 and NCI-H1944 human lung adenocarcinoma cell lines and their antimicrobial activities against Staphylococcus aureus and Saccharomyces cerevisiae. As a result, compounds 1–4 showed moderate cytotoxicity, with IC₅₀ values of 6.52~45.20 µM. Compounds 1 and 3 exhibited significant antimicrobial activities against S. aureus and S. cerevisiae, with an MIC80 of 11.1~30.0 µg/mL. Full article

(This article belongs to the Section Natural Products Chemistry)

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23 pages, 869 KiB

Open AccessArticle

Synthesis of Enantiostructured Triacylglycerols Possessing a Saturated Fatty Acid, a Polyunsaturated Fatty Acid and an Active Drug Intended as Novel Prodrugs

by Lena Rós Jónsdóttir and Gudmundur G. Haraldsson

Molecules 2024, 29(23), 5745; https://doi.org/10.3390/molecules29235745 - 5 Dec 2024

Abstract

This report describes the asymmetric synthesis of a focused library of enantiopure structured triacylglycerols (TAGs) comprised of a single saturated fatty acid (C6, C8, C10, C12, C14 or C16), a pure bioactive n-3 polyunsaturated fatty acid (EPA or DHA) and a potent drug [...] Read more.

This report describes the asymmetric synthesis of a focused library of enantiopure structured triacylglycerols (TAGs) comprised of a single saturated fatty acid (C6, C8, C10, C12, C14 or C16), a pure bioactive n-3 polyunsaturated fatty acid (EPA or DHA) and a potent drug (ibuprofen or naproxen) intended as a novel type of prodrug. One of the terminal sn-1 or sn-3 positions of the glycerol backbone is occupied with a saturated fatty, the remaining one with a PUFA, and the drug entity is present in the sn-2 position. This was accomplished by a six-step chemoenzymatic approach starting from enantiopure (R)- and (S)-solketals. The highly regioselective immobilized Candida antarctica lipase (CAL-B) played a crucial role in the regiocontrol of the synthesis. All combinations, a total of 48 such prodrug TAGs, were prepared, isolated and fully characterized, along with 60 acylglycerol intermediates, obtained in very high to excellent yields. Full article

(This article belongs to the Section Organic Chemistry)

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27 pages, 4630 KiB

Open AccessReview

Glutamate: Molecular Mechanisms and Signaling Pathway in Alzheimer’s Disease, a Potential Therapeutic Target

by Nidhi Puranik and Minseok Song

Molecules 2024, 29(23), 5744; https://doi.org/10.3390/molecules29235744 - 5 Dec 2024

Abstract

Gamma-glutamate is an important excitatory neurotransmitter in the central nervous system (CNS), which plays an important role in transmitting synapses, plasticity, and other brain activities. Nevertheless, alterations in the glutamatergic signaling pathway are now accepted as a central element in Alzheimer’s disease (AD) [...] Read more.

Gamma-glutamate is an important excitatory neurotransmitter in the central nervous system (CNS), which plays an important role in transmitting synapses, plasticity, and other brain activities. Nevertheless, alterations in the glutamatergic signaling pathway are now accepted as a central element in Alzheimer’s disease (AD) pathophysiology. One of the most prevalent types of dementia in older adults is AD, a progressive neurodegenerative illness brought on by a persistent decline in cognitive function. Since AD has been shown to be multifactorial, a variety of pharmaceutical targets may be used to treat the condition. N-methyl-D-aspartic acid receptor (NMDAR) antagonists and acetylcholinesterase inhibitors (AChEIs) are two drug classes that the Food and Drug Administration has authorized for the treatment of AD. The AChEIs approved to treat AD are galantamine, donepezil, and rivastigmine. However, memantine is the only non-competitive NMDAR antagonist that has been authorized for the treatment of AD. This review aims to outline the involvement of glutamate (GLU) at the molecular level and the signaling pathways that are associated with AD to demonstrate the drug target therapeutic potential of glutamate and its receptor. We will also consider the opinion of the leading authorities working in this area, the drawback of the existing therapeutic strategies, and the direction for the further investigation. Full article

(This article belongs to the Special Issue Discovering New Drug Targets for Neurodegenerative Disorders)

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23 pages, 2979 KiB

Open AccessFeature PaperArticle

Impact of Alkyl Spacer and Side Chain on Antimicrobial Activity of Monocationic and Dicationic Imidazolium Surface-Active Ionic Liquids: Experimental and Theoretical Insights

by Marta Wojcieszak, Sylwia Zięba, Alina T. Dubis, Maciej Karolak, Łukasz Pałkowski, Agnieszka Marcinkowska, Andrzej Skrzypczak, Alicja Putowska and Katarzyna Materna

Molecules 2024, 29(23), 5743; https://doi.org/10.3390/molecules29235743 - 5 Dec 2024

Abstract

This study investigates a series of surface-active ionic liquids (SAILs), including both imidazolium monocationic and dicationic compounds. These compounds are promising candidates, as they combine unique surface properties with antimicrobial activity, aligning with modern trends in chemistry. The research encompasses synthesis, thermal analysis, [...] Read more.

This study investigates a series of surface-active ionic liquids (SAILs), including both imidazolium monocationic and dicationic compounds. These compounds are promising candidates, as they combine unique surface properties with antimicrobial activity, aligning with modern trends in chemistry. The research encompasses synthesis, thermal analysis, and topographical assessment, focusing on the impact of the amphiphilic cationic moiety, alkyl chain length, and the spatial relationship between the imidazolium ring and the phenyl substituent on the compounds’ physicochemical behavior. An added value of this work lies in the integration of theoretical calculations related to their behavior in solution and at the air–water interface, revealing spontaneous adsorption (negative Gibbs free energy of adsorption values, ΔG⁰_ads). The results indicate that dicationic imidazolium SAILs have a greater tendency to form micelles but are less effective at reducing surface tension compared to their monocationic counterparts. Topography analyses of SAILs with 12 carbon atoms further highlight these differences. Notably, the dicationic SAIL with 12 carbon atoms in the spacer exhibited an impressive MIC of 0.007 mmol L⁻¹ against Candida albicans, consistent with findings showing that dicationic SAILs outperformed conventional antifungal agents, such as amphotericin B and fluconazole, at equivalent concentrations. Overall, the synthesized SAILs demonstrate superior surface activity compared to commercial surfactants and show potential as disinfectant agents. Full article

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15 pages, 3266 KiB

Open AccessArticle

Antiviral Activity of (1S,9aR)-1-[(1,2,3-Triazol-1-yl)methyl]octahydro-1H-quinolizines from the Alkaloid Lupinine

by Zhangeldy S. Nurmaganbetov, Oralgazy A. Nurkenov, Andrei I. Khlebnikov, Serik D. Fazylov, Roza B. Seidakhmetova, Zhanar K. Tukhmetova, Altynaray T. Takibayeva, Gaukhar Khabdolda, Zhanar B. Rakhimberlinova, Aigul K. Kaldybayeva and Elvira E. Shults

Molecules 2024, 29(23), 5742; https://doi.org/10.3390/molecules29235742 - 5 Dec 2024

Abstract

Influenza is a disease of significant morbidity and mortality. The number of anti-influenza drugs is small; many of them stimulate the appearance of resistant strains. This article presents the results of assessing the antiviral activity of 1,2,3-triazole-containing derivatives of alkaloid lupinine for their [...] Read more.

Influenza is a disease of significant morbidity and mortality. The number of anti-influenza drugs is small; many of them stimulate the appearance of resistant strains. This article presents the results of assessing the antiviral activity of 1,2,3-triazole-containing derivatives of alkaloid lupinine for their ability to suppress the reproduction of orthomyxoviruses (influenza viruses: A/Vladivostok/2/09 (H1N1) and A/Almaty/8/98 (H3N2)). The ability of (1S,9aR)-1-[(1,2,3-triazol-1-yl)-methyl]octahydro-1H-quinolizines with aryl-, 4-((4-formylphenoxy)methyl)- or 4-((3-tert-butyl-5-ethyl-2-hydroxy-benzoyloxy)methyl)- substituents at the C-4 position of the triazole ring to reduce the infectivity of the virus when processing virus-containing material was established, indicating good prospects for the studied compounds as virucidal agents affecting extracellular virions. The experimental results demonstrated that the triazolyl lupinine derivatives exhibited varying degrees of affinity for both hemagglutinin and neuraminidase proteins. Furthermore, these compounds demonstrated inhibitory effects on the replication of influenza viruses with different antigenic subtypes. The obtained biological data are in agreement with the results of molecular docking, which showed strong binding energies of the investigated compounds under study with biological targets—hemagglutinin and neuraminidase proteins. Following the evaluation of antiviral efficacy among the studied triazolyl derivatives of lupinine, four compounds have been identified for subsequent comprehensive in vitro and in vivo investigations to further elucidate their antiviral properties. Full article

(This article belongs to the Section Medicinal Chemistry)

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