Molecules

20 pages, 12650 KiB

Open AccessArticle

Study of the Process of Calcium Sulfide-Based Luminophore Formation from Phosphogypsum

by Marina A. Egorova, Daniil I. Monastyrskiy, Oleg A. Medennikov, Nina P. Shabelskaya, Zlatislava D. Khliyan, Vera A. Ulyanova, Sergey I. Sulima and Elena V. Sulima

Molecules 2024, 29(22), 5486; https://doi.org/10.3390/molecules29225486 - 20 Nov 2024

Viewed by 293

Abstract

One of the priority goals of sustainable socio-economic development for the period up to 2030 is providing food for the planet’s population. This entails an increase in the output of mineral fertilizers and, consequently, an increase in the quantities of solid industrial waste. [...] Read more.

One of the priority goals of sustainable socio-economic development for the period up to 2030 is providing food for the planet’s population. This entails an increase in the output of mineral fertilizers and, consequently, an increase in the quantities of solid industrial waste. Phosphogypsum, a by-product of phosphate fertilizer production from apatite ore, is one example of such waste. The problem of solid industrial waste recycling is urgent. The present study examines the process of converting calcium sulfate, in the form of a reagent, and phosphogypsum into a composite material of calcium sulfate/sulfide. An environmentally friendly material, sucrose, is used as a reducing agent. Reduced phosphogypsum (as well as calcium sulfate) luminescence is suggested to be associated with the formation of a CaS/CaSO₄ composite material. The synthesized materials are characterized by X-ray phase analysis, X-ray photoelectron spectroscopy, elemental analysis, and calcium sulfide qualitative and quantitative content in the samples. It is shown that in the reduction process at the phase contact point, crystal grids are formed with a significant number of defects, which contributes to the convergence of some of the energy levels of the calcium cation and sulfide anion, facilitating the transitions of electrons from the valence zone to the core zone and the formation of luminescence centers (cross-luminescence). Both samples of reduced phosphogypsum and alkaline earth metal sulfates are found to exhibit luminescence properties under ultraviolet radiation. The data obtained open up broad prospects for the use of solid industrial waste for the synthesis of new materials. Full article

(This article belongs to the Special Issue Solid Waste and Fly Ash Chemical Treatment Methods)

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24 pages, 3623 KiB

Open AccessArticle

In Silico Mass Spectrometric Fragmentation and Liquid Chromatography with Tandem Mass Spectrometry (LC-MS/MS) Betalainic Fingerprinting: Identification of Betalains in Red Pitaya

by Jesús Alfredo Araujo-León, Ivonne Sánchez-del Pino, Ligia Guadalupe Brito-Argáez, Sergio R. Peraza-Sánchez, Rolffy Ortiz-Andrade and Victor Aguilar-Hernández

Molecules 2024, 29(22), 5485; https://doi.org/10.3390/molecules29225485 - 20 Nov 2024

Viewed by 761

Abstract

Betalains, which contain nitrogen and are water soluble, are the pigments responsible for many traits of plants and biological activities in different organisms that do not produce them. To better annotate and identify betalains using a spectral library and fingerprint, a database catalog [...] Read more.

Betalains, which contain nitrogen and are water soluble, are the pigments responsible for many traits of plants and biological activities in different organisms that do not produce them. To better annotate and identify betalains using a spectral library and fingerprint, a database catalog of 140 known betalains (112 betacyanins and 28 betaxanthins) was made in this work to simplify betalain identification in mass spectrometry analysis. Fragmented peaks obtained using MassFrontier, along with chemical structures and protonated precursor ions for each betalain, were added to the database. Product ions made in MS/MS and multistage MS analyses of betanin, beetroot extract, and red pitaya extract revealed the fingerprint of betalains, distinctive ions of betacyanin, betacyanin derivatives such as decarboxylated and dehydrogenated betacyanins, and betaxanthins. A distinctive ion with m/z 211.07 was found in betaxanthins. By using the fingerprint of betalains in the analysis of red pitaya extracts, the catalog of betalains in red pitaya was expanded to 86 (31 betacyanins, 36 betacyanin derivatives, and 19 betaxanthins). Four unknown betalains were detected to have the fingerprint of betalains, but further research will aid in revealing the complete structure. Taken together, we envisage that the further use of the fingerprint of betalains will increase the annotation coverage of identified molecules in studies related to revealing the biological function of betalains or making technologies based on these natural colorants. Full article

(This article belongs to the Special Issue State-of-the-Art Analytical Technologies for Food Safety, Quality and Authenticity Assessment)

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44 pages, 6057 KiB

Open AccessReview

State of the Art and Challenges in Complete Benzene Oxidation: A Review

by Tatyana Tabakova

Molecules 2024, 29(22), 5484; https://doi.org/10.3390/molecules29225484 - 20 Nov 2024

Viewed by 355

Abstract

Increased levels and detrimental effects of volatile organic compounds (VOCs) on air quality and human health have become an important issue in the environmental field. Benzene is classified as one of the most hazardous air pollutants among non-halogenated aromatic hydrocarbons with toxic, carcinogenic, [...] Read more.

Increased levels and detrimental effects of volatile organic compounds (VOCs) on air quality and human health have become an important issue in the environmental field. Benzene is classified as one of the most hazardous air pollutants among non-halogenated aromatic hydrocarbons with toxic, carcinogenic, and mutagenic effects. Various technologies have been applied to decrease harmful emissions from various sources such as petrochemistry, steel manufacturing, organic chemical, paint, adhesive, and pharmaceutical production, vehicle exhausts, etc. Catalytic oxidation to CO₂ and water is an attractive approach to VOC removal due to high efficiency, low energy consumption, and the absence of secondary pollution. However, catalytic oxidation of the benzene molecule is a great challenge because of the extraordinary stability of its six-membered ring structure. Developing highly efficient catalysts is of primary importance for effective elimination of benzene at low temperatures. This review aims to summarize and discuss some recent advances in catalyst composition and preparation strategies. Advantages and disadvantages of using noble metal-based catalysts and transition metal oxide-based catalysts are addressed. Effects of some crucial factors such as catalyst support nature, metal particle size, electronic state of active metal, redox properties, reactivity of lattice oxygen and surface adsorbed oxygen on benzene removal are explored. Thorough elucidation of reaction mechanisms in benzene oxidation is a prerequisite to develop efficient catalysts. Benzene oxidation mechanisms are analyzed based on in situ catalyst characterization, reaction kinetics, and theoretical simulation calculations. Considering the role of oxygen vacancies in improving catalytic performance, attention is given to oxygen defect engineering. Catalyst deactivation due to coexistence of water vapor and other pollutants, e.g., sulfur compounds, is discussed. Future research directions for rational design of catalysts for complete benzene oxidation are provided. Full article

(This article belongs to the Special Issue Feature Papers in Applied Chemistry: 3rd Edition)

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43 pages, 1635 KiB

Open AccessReview

Research Progress on Sesquiterpenes from the Genus Ainsliaea

by Hui Zhang, Ru-Ru Sun, Ya-Feng Liu, Xin Guo, Chong-Long Li, Ze-Dong Nan and Zhi-Bo Jiang

Molecules 2024, 29(22), 5483; https://doi.org/10.3390/molecules29225483 - 20 Nov 2024

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Abstract

Sesquiterpenes constitute the principal components of the genus Ainsliaea, encompassing guaiane, germacrane, eudesmane, and polymer sesquiterpene lactones types. These secondary metabolites exhibit diverse pharmacological activities, including antitumor, antibacterial, anti-inflammatory, antiviral, antioxidant, hepatoprotective, and neuroprotective effects. Through a comprehensive literature search of the [...] Read more.

Sesquiterpenes constitute the principal components of the genus Ainsliaea, encompassing guaiane, germacrane, eudesmane, and polymer sesquiterpene lactones types. These secondary metabolites exhibit diverse pharmacological activities, including antitumor, antibacterial, anti-inflammatory, antiviral, antioxidant, hepatoprotective, and neuroprotective effects. Through a comprehensive literature search of the Web of Science, PubMed, SciFinder, and CNKI databases, it was discovered that there are as many as 145 main sesquiterpenoids in the genus Ainsliaea. However, the nuclear magnetic resonance (NMR) data for the sesquiterpenes in this genus have not been systematically compiled and summarized. Therefore, this review aims to highlight the chemical structures, NMR data, and pharmacological activities of sesquiterpenes in Ainsliaea. By meticulously analyzing published scholarly literature, our goal is to provide a solid foundation for further exploration of new sesquiterpenes and extensive utilization of this genus. Full article

(This article belongs to the Section Photochemistry)

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14 pages, 6320 KiB

Open AccessArticle

Interactions Between Cationic Micellar Solution and Aromatic Hydrotropes with Subtle Structural Variations

by Bin Liu, Shuo Yin, Xia Wu, Xilian Wei, Huifang Xu, Jing Li and Dongmei Lv

Molecules 2024, 29(22), 5482; https://doi.org/10.3390/molecules29225482 - 20 Nov 2024

Viewed by 219

Abstract

Wormlike micelles (WLMs) with tunable viscoelastic characteristics have emerged as indispensable smart materials with a wide range of applications, which have garnered intense interest over the past few decades. However, quantitatively predicting the effect of various hydrotropes on the rheological behaviors of WLMs [...] Read more.

Wormlike micelles (WLMs) with tunable viscoelastic characteristics have emerged as indispensable smart materials with a wide range of applications, which have garnered intense interest over the past few decades. However, quantitatively predicting the effect of various hydrotropes on the rheological behaviors of WLMs remains a challenge. In this article, micelles were formed in a mixture of 3-hexadecyloxy-2-hydroxypropyltrimethylammonium bromide (R₁₆HTAB) and aromatic hydrotropes (e.g., sodium benzoate, sodium cinnamate and their derivatives, respectively) in an aqueous solution. The phase behavior, viscoelasticity and thickening mechanism were systematically studied by macroscopic observation, rheological measurements, electrostatic potential analysis and cryogenic transmission electron microscopy (Cryo-TEM). Rheological measurements were used to probe the remarkable viscoelastic properties of micelles stemming from their lengthening and entanglement under the interaction between R₁₆HTAB and hydrotropes with structural variations. For an equimolar system of R₁₆HTAB and cosolute (40 mM), the relaxation time decreases in the following order: SpMB > SoHB > S4MS > SmMB > S5MS > SB > SmHB > SoMB > SpHB. These results allow us to predict the possible rules for the self-assembly of R₁₆HTAB and aromatic hydrotropes, which is conductive to directionally designing and synthesizing smart wormlike micelles. Full article

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17 pages, 3901 KiB

Open AccessArticle

Experimental and DFT Approaches to Physico-Chemical Properties of Bioactive Resveratrol Analogues

by Borislav Kovačević, Ivana Šagud, Katarina Marija Drmić, Milena Mlakić, Irena Škorić and Sandra Babić

Molecules 2024, 29(22), 5481; https://doi.org/10.3390/molecules29225481 - 20 Nov 2024

Viewed by 307

Abstract

Acetylcholinesterase and butyrylcholinesterase are two related enzymes that represent pharmacologically suitable targets in neurodegenerative disorders, given their physiological roles in the body. The treatment of neurodegenerative disorders currently includes common reversible cholinesterase inhibitors. Resveratrol analogues, as the molecules in focus, have shown the [...] Read more.

Acetylcholinesterase and butyrylcholinesterase are two related enzymes that represent pharmacologically suitable targets in neurodegenerative disorders, given their physiological roles in the body. The treatment of neurodegenerative disorders currently includes common reversible cholinesterase inhibitors. Resveratrol analogues, as the molecules in focus, have shown the very strong inhibition potential of cholinesterases. In this research, experimental and DFT approaches for their pK_a value determination were carried out knowing that pK_a is very important for predicting the ADMET properties of the potentially bioactive molecules and their behavior in the environment. An in silico study was used to calculate more indicators about the absorption and distribution in the human body. Among the investigated compounds, the weakest acid was experimentally detected and confirmed using three computational models. Additionally performed calculations provided access to the potential of each resveratrol analogue to engage in both π-π stacking and hydrogen bond interactions in the active site of the enzyme crucial for the stability of the ligand–enzyme complex. Full article

(This article belongs to the Special Issue Heterocyclic Bioactive Small Molecules: Advances in Structure Analysis and Drug Discovery in Heterocyclic Chemistry)

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22 pages, 8070 KiB

Open AccessArticle

Structure, Optical and Electrical Properties of Nb(Zn) Doped Sol–Gel ITO Films: Effect of Substrates and Dopants

by Mariuca Gartner, Anna Szekeres, Simeon Simeonov, Maria Covei, Mihai Anastasescu, Silviu Preda, Jose Maria Calderon-Moreno, Luminita Predoana, Hermine Stroescu, Daiana Mitrea and Madalina Nicolescu

Molecules 2024, 29(22), 5480; https://doi.org/10.3390/molecules29225480 - 20 Nov 2024

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Abstract

We present comparative studies of sol–gel ITO multilayered films undoped and doped with Nb or Zn (4 at.%). The films were obtained by successive depositions of five layers using the dip-coating sol–gel method on microscopic glass, SiO₂/glass, and Si substrates. The [...] Read more.

We present comparative studies of sol–gel ITO multilayered films undoped and doped with Nb or Zn (4 at.%). The films were obtained by successive depositions of five layers using the dip-coating sol–gel method on microscopic glass, SiO₂/glass, and Si substrates. The influence of the type of substrates and dopant atoms on the structure and optical properties of the sol–gel ITO thin films is examined and discussed in detail. XRD patterns of these layers showed a polycrystalline structure with an average crystallite size of <11 nm. Raman spectroscopy confirmed the chemical bonding of dopants with oxygen and showed the absence of crystallized Nb(Zn)-oxide particles, indicated by the XRD pattern. Spectroscopic Ellipsometry and AFM imaging revealed a clear dependence of the optical parameters and surface morphology of the ITO and ITO:Nb(Zn) thin films on the type of substrates and dopants. The analysis of the current-voltage and capacitance-voltage characteristics of the Al/ITO/Si structures revealed the presence of charge carrier traps in the ITO bulk and the ITO-Si interface. The densities of these traps are obtained and the character of the current transport mechanism is established. Full article

(This article belongs to the Special Issue Chemical Research on High-Performance Composites)

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16 pages, 3411 KiB

Open AccessArticle

Anti-Aging and Anti-Inflammatory Effects of Compounds from Fresh Panax ginseng Roots: A Study on TNF-α/IFN-γ-Induced Skin Cell Damage

by Minseo Kang, Somin Park, So-Ri Son, Yedam Noh, Dae Sik Jang and Sullim Lee

Molecules 2024, 29(22), 5479; https://doi.org/10.3390/molecules29225479 - 20 Nov 2024

Viewed by 347

Abstract

Panax ginseng (Korean ginseng) is renowned for its health-promoting properties, attributed to its bioactive compounds, including saponins, polyphenols, and polysaccharides, which possess both antioxidant and anti-aging activities. This study investigated the anti-aging and anti-inflammatory effects of compounds isolated from the hot water extract [...] Read more.

Panax ginseng (Korean ginseng) is renowned for its health-promoting properties, attributed to its bioactive compounds, including saponins, polyphenols, and polysaccharides, which possess both antioxidant and anti-aging activities. This study investigated the anti-aging and anti-inflammatory effects of compounds isolated from the hot water extract of fresh P. ginseng roots, evaluating their resistance to TNF-α/IFN-γ-induced skin cell damage. Among 14 compounds, ginsenoside Rf (compound 2) showed significant multi-target effects. In NHDFs, ginsenoside Rf and others effectively reduced intracellular ROS, demonstrating strong antioxidant properties. Additionally, they inhibited MMP-1 expression, a key enzyme in collagen degradation, and promoted pro-collagen Type I synthesis, countering the negative effects of TNF-α and supporting skin health. Further analysis showed that ginsenoside Rf reduced the secretion of inflammatory cytokines like IL-1β and IL-6, exhibiting anti-inflammatory effects. It also promoted the expression of crucial skin barrier proteins, including LOR, AQP3, FLG, and KRT1 in TNF-α/IFN-γ-stimulated NHEKs, enhancing skin hydration and structural integrity. These results suggest that compounds from P. ginseng roots, especially ginsenoside Rf, hold promise as skincare agents targeting skin aging and inflammation. Future research should further explore their mechanisms and optimize their applications in dermatological treatments. Full article

(This article belongs to the Special Issue Chemical Biology in Asia)

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15 pages, 4125 KiB

Open AccessArticle

Matrix Solid-Phase Dispersion Procedure for Determination of Antibiotics and Metabolites in Mussels: Application in Exposure Bioassays

by Carmen Mejías, Tainá G. Fonseca, Noelia García-Criado, Julia Martín, Juan Luis Santos, Irene Aparicio and Esteban Alonso

Molecules 2024, 29(22), 5478; https://doi.org/10.3390/molecules29225478 - 20 Nov 2024

Viewed by 321

Abstract

The presence of antibiotics in seafood for human consumption may pose a risk for consumers. Furthermore, some marine organisms, such as mussels, can result in appropriate bioindicators of marine contamination. In this work, a multiresidue analytical methodology suitable for the determination of antibiotics [...] Read more.

The presence of antibiotics in seafood for human consumption may pose a risk for consumers. Furthermore, some marine organisms, such as mussels, can result in appropriate bioindicators of marine contamination. In this work, a multiresidue analytical methodology suitable for the determination of antibiotics and metabolites in mussels is proposed. The target compounds include three sulphonamides and trimethoprim (TMP) and six of their main metabolites. Sample treatment involves extraction and clean-up in a single step using matrix solid-phase dispersion with acetonitrile. Analytical determination was carried out by liquid chromatography–tandem mass spectrometry. Good linearity (R² > 0.99), accuracy (from 80.8 to 118%), and limits of quantification (lower than 5 ng g⁻¹ (dry matter, dm)) were obtained for all selected compounds. The method was applied to the determination of antibiotics in mussel samples from an exposure assay with contaminated seawater with TMP and sulfamethoxazole (SMX). Both antibiotics were detected in the analysed samples with concentrations up to 77.5 ng g⁻¹ dm. TMP was bioconcentrated to a higher extent than SMX, attributable to its higher hydrophobicity. None of the metabolites were detected. These results demonstrate that Mytilus galloprovincialis is a suitable bioindicator to assess marine pollution. Full article

(This article belongs to the Section Analytical Chemistry)

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11 pages, 3628 KiB

Open AccessArticle

Facile Preparation of High-Performance Polythiophene Derivative and Effect of Torsion Angle Between Thiophene Rings on Electrochromic Color Change

by Qingfu Guo, Chao Sun, Yiran Li, Kaoxue Li and Xishi Tai

Molecules 2024, 29(22), 5477; https://doi.org/10.3390/molecules29225477 - 20 Nov 2024

Viewed by 266

Abstract

The electrochromic phenomenon of conducting polymer is mainly dominated by the π-π* band transition. The π conjugation is influenced by the coplanarity between polymer units, deviations from which can lead to an increased ionization potential and band gap values. In order to investigate [...] Read more.

The electrochromic phenomenon of conducting polymer is mainly dominated by the π-π* band transition. The π conjugation is influenced by the coplanarity between polymer units, deviations from which can lead to an increased ionization potential and band gap values. In order to investigate the effect of plane distortion angle on electrochromic color in the main chain structure of polymerization, high-performance poly(3,3′-dimethyl-2,2′-bithiophene) (PDMeBTh) with a large plane distortion angle is successfully synthesized in boron trifluoride diethyl etherate (BFEE) by the electrochemical anodic oxidation method. The electrochemical and thermal properties of PDMeBTh prepared from BFEE and ACN/TBATFB are compared. The electrochromic properties of PDMeBTh are systematically investigated. The PDMeBTh shows a different color change (orange-yellow in the neutral state) compared to poly (3-methylthiophene) (light-red in the neutral state) due to the large torsion angle between thiophene rings of the main polymer chain. The optical contrast, response time, and coloring efficiency (CE) of the prepared PDMeBTh are also studied, which shows good electrochromic properties. For practical applications, an electrochromic device is fabricated by the PDMeBTh and PEDOT. The color of the device can be reversibly changed between orange-yellow and dark blue. The light contrast of the device is 27% at 433 nm and 61% at 634 nm. The CE value of the device is 403 cm² C⁻¹ at 433 nm and 577 cm² C⁻¹ at 634 nm. The constructed device also has good open circuit memory and electrochromic stability, showing good potential for practical applications. Full article

(This article belongs to the Section Macromolecular Chemistry)

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16 pages, 5121 KiB

Open AccessArticle

Mutational Analysis of Substrate Recognition in Trypsin-like Protease Cocoonase: Protein Memory Induced by Alterations in Substrate-Binding Site

by Nana Sakata, Shigeru Shimamoto, Yuri Murakami, Orika Ashida, Toshiki Takei, Mitsuhiro Miyazawa and Yuji Hidaka

Molecules 2024, 29(22), 5476; https://doi.org/10.3390/molecules29225476 - 20 Nov 2024

Viewed by 256

Abstract

To investigate the substrate recognition mechanism of trypsin-like protease cocoonase (CCN), mutational analyses were conducted at key substrate recognition sites, Asp187 and Ser188, and their effects on substrate specificity and enzymatic activity were evaluated. Mutants with the Asp187 substitution exhibited a significant reduction [...] Read more.

To investigate the substrate recognition mechanism of trypsin-like protease cocoonase (CCN), mutational analyses were conducted at key substrate recognition sites, Asp187 and Ser188, and their effects on substrate specificity and enzymatic activity were evaluated. Mutants with the Asp187 substitution exhibited a significant reduction in catalytic activity compared with the wild-type enzyme, whereas the Ser188 mutants displayed a comparatively minor effect on activity. This indicates that Asp187 plays a crucial role in catalytic function, whereas Ser188 serves a complementary role in substrate recognition. Interestingly, the substitution of the Asp187 to Glu or Ser caused novel substrate specificities, resulting in the recognition of Orn and His residues. In addition, when Asp187 and Ser188 were substituted with acidic residues (Glu or Asp), both the precursor proCCN and mature CCN proteins retained highly similar secondary and tertiary structures. This reveals that the structural characteristics of precursor proteins are maintained in the mature proteins, potentially influencing substrate recognition and catalytic function. These findings suggest that the pro-regions of these mutants interact much more tightly with the mature enzyme than in the wild-type CCN. These results provide fruitful insights into the structural determinants governing substrate recognition in enzyme variants. Full article

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

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19 pages, 2323 KiB

Open AccessArticle

Effect of Different Extraction Techniques on Phenolic Profile and Phytochemical Potential of Gymnema inodorum Leaf Extract

by Muhammad Hassnain Haideri, Titi Phanjaroen, Wiritphon Khiaolaongam, Thanarat Boonchalaem, Jiraporn Laoung-on, Supakit Chaipoot, Surat Hongsibsong, Kongsak Boonyapranai and Sakaewan Ounjaijean

Molecules 2024, 29(22), 5475; https://doi.org/10.3390/molecules29225475 - 20 Nov 2024

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Abstract

The therapeutic potential of plant extracts has attracted significant interest, especially regarding indigenous species with health-promoting properties. Gymnema inodorum, native to Northern Thailand, is recognized for its rich phytochemical profile; however, the impact of various extraction techniques on its phenolic composition and [...] Read more.

The therapeutic potential of plant extracts has attracted significant interest, especially regarding indigenous species with health-promoting properties. Gymnema inodorum, native to Northern Thailand, is recognized for its rich phytochemical profile; however, the impact of various extraction techniques on its phenolic composition and bioactivity remains underexplored. Optimizing extraction methods is essential to enhance the pharmacological efficacy of this plant’s bioactive compounds. This study investigated the influence of four extraction methods—ethanol maceration, ethanol reflux, aqueous decoction, and microwave-assisted extraction—on the bioactive profile of G. inodorum leaves, with a focus on the phenolic content and biological activities. Antioxidant activities were evaluated using DPPH, ABTS, and FRAP assays, while the total phenolic and flavonoid contents were quantified by colorimetric methods. High-Performance Liquid Chromatography (HPLC) quantified gymnemic acid and key phenolic compounds. Among the methods, ethanol reflux yielded the highest antioxidant activities (DPPH and ABTS scavenging), with a total phenolic content of 82.54 mg GAE/g and flavonoid content of 31.90 mg QE/g. HPLC analysis identified sinapic acid, myricetin, and p-hydroxybenzoic acid as major phenolics. Furthermore, the ethanol reflux extract displayed potent anti-diabetic activity, with IC₅₀ values of 13.36 mg/mL for α-amylase and 7.39 mg/mL for α-glucosidase, as well as strong anti-inflammatory activity (IC₅₀ of 1.6 mg/mL) and acetylcholinesterase inhibition (IC₅₀ of 1.2 mg/mL). These findings suggest that ethanol reflux extraction is a highly effective method for producing bioactive-rich G. inodorum extracts, with substantial pharmacological potential for developing herbal remedies and nutraceuticals, particularly in enhancing therapeutic approaches for diabetes and other health-related conditions. Full article

(This article belongs to the Special Issue Natural Bioactive Compounds from Traditional Asian Plants)

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16 pages, 2124 KiB

Open AccessArticle

An Unexpected Formation of Spiro Isoxazoline-Dihydrofurane Compounds from Substituted Ketofurfuryl Alcohols

by Claire Cuyamendous, Mathieu Yves Laurent and Christine Saluzzo

Molecules 2024, 29(22), 5474; https://doi.org/10.3390/molecules29225474 - 20 Nov 2024

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Abstract

Oximation of substituted ketofurfuryl alcohols in the presence of hydroxylamine hydrochloride and pyridine in ethanol as solvent led to a new class of spiro derivatives presenting a 7-methylene-1,6-dioxa-2-azaspiro [4.4] nona-2,8-diene skeleton along with, in some cases, the predictable oxime. The structures of such [...] Read more.

Oximation of substituted ketofurfuryl alcohols in the presence of hydroxylamine hydrochloride and pyridine in ethanol as solvent led to a new class of spiro derivatives presenting a 7-methylene-1,6-dioxa-2-azaspiro [4.4] nona-2,8-diene skeleton along with, in some cases, the predictable oxime. The structures of such spiro compounds were determined by 2D NMR spectroscopy. The suggested formation of this skeleton involves an in situ oximation/dehydration/S_N’ cascade reaction. Full article

(This article belongs to the Section Organic Chemistry)

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19 pages, 3522 KiB

Open AccessArticle

The Relationship Between Spin Crossover (SCO) Behaviors, Cation and Ligand Motions, and Intermolecular Interactions in a Series of Anionic SCO Fe(III) Complexes with Halogen-Substituted Azobisphenolate Ligands

by Mai Hirota, Suguru Murata, Takahiro Sakurai, Hitoshi Ohta and Kazuyuki Takahashi

Molecules 2024, 29(22), 5473; https://doi.org/10.3390/molecules29225473 - 20 Nov 2024

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Abstract

To investigate the halogen substitution effect on the anionic spin crossover (SCO) complexes, azobisphenolate ligands with 5,5′-dihalogen substituents from fluorine to iodine were synthesized, and their anionic Fe^III complexes 1F, 1Cl, 1Br, and 1I were isolated. The temperature dependence [...] Read more.

To investigate the halogen substitution effect on the anionic spin crossover (SCO) complexes, azobisphenolate ligands with 5,5′-dihalogen substituents from fluorine to iodine were synthesized, and their anionic Fe^III complexes 1F, 1Cl, 1Br, and 1I were isolated. The temperature dependence of magnetic susceptibility and crystal structure revealed that 1F, 1Cl, and 1Br are all isostructural and exhibit SCO with the rotational motion of the cation and ligands, whereas 1I shows incomplete SCO. Note that 1Cl and 1Br showed irreversible and reversible cooperative SCO transitions, respectively. Short intermolecular contacts between the Fe^III complex anions were found despite Coulomb repulsions for all the complexes. The topological analysis of the electron density distributions revealed the existence of X···X halogen bonds, C–H···X, C–H···N, and C–H···O hydrogen bonds, and C–H···π interactions are evident. The dimensionality of intermolecular interactions is suggested to be responsible for the cooperative SCO transitions in 1Cl and 1Br, whereas the disorder due to the freezing of ligand rotations in 1Cl is revealed to inhibit the SCO cooperativity. Full article

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

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10 pages, 1755 KiB

Open AccessArticle

Photochemical Hydroxyl Group Abstraction from N-Hydroxypyridine-2(1H)-thione Isolated in a Solid Hydrogen Matrix: Photogeneration of 2-Mercaptopyridine

by Hanna Rostkowska, Maciej J. Nowak, Igor Reva and Leszek Lapinski

Molecules 2024, 29(22), 5472; https://doi.org/10.3390/molecules29225472 - 20 Nov 2024

Viewed by 295

Abstract

Monomers of N-hydroxypyridine-2(1H)-thione were isolated in low-temperature matrices of solid normal hydrogen (n-H₂). The matrix-isolated compound was irradiated with UV-B (λ = 305 nm) or UV-A (λ > 360 nm) light. Upon such irradiation, the initial form of [...] Read more.

Monomers of N-hydroxypyridine-2(1H)-thione were isolated in low-temperature matrices of solid normal hydrogen (n-H₂). The matrix-isolated compound was irradiated with UV-B (λ = 305 nm) or UV-A (λ > 360 nm) light. Upon such irradiation, the initial form of N-hydroxypyridine-2(1H)-thione was completely consumed and converted into photoproducts. 2-Mercaptopyridine and water were identified as the main products of these photochemical transformations. Identification of photoproduced 2-mercaptopyridine is unquestionable. It is based on the identity of two sets of IR bands: (i) the bands observed in the IR spectrum recorded (in a separate experiment) for monomers of 2-mercaptopyridine trapped in an n-H₂ matrix and (ii) a set of IR bands observed in the spectrum recorded after UV irradiation of N-hydroxypyridine-2(1H)-thione. It should be emphasized that the UV-induced processes, occurring for N-hydroxypyridine-2(1H)-thione isolated in an n-H₂ matrix, lead to products that are significantly different from those generated from the compound trapped in solid Ar or in solid N₂. Full article

(This article belongs to the Special Issue Feature Papers in Photochemistry and Photocatalysis)

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17 pages, 1926 KiB

Open AccessReview

Cannabigerol (CBG): A Comprehensive Review of Its Molecular Mechanisms and Therapeutic Potential

by Shijia Li, Weini Li, Naseeb Kaur Malhi, Junwei Huang, Quanqi Li, Ziwei Zhou, Ruiheng Wang, Jiangling Peng, Tong Yin and Honggen Wang

Molecules 2024, 29(22), 5471; https://doi.org/10.3390/molecules29225471 - 20 Nov 2024

Viewed by 401

Abstract

Cannabigerol (CBG), a non-psychoactive cannabinoid found in cannabis, has emerged as a promising therapeutic agent with a diverse range of potential applications. Unlike its well-known counterpart tetrahydrocannabinol (THC), CBG does not induce intoxication, making it an attractive option in the clinic. Recent research [...] Read more.

Cannabigerol (CBG), a non-psychoactive cannabinoid found in cannabis, has emerged as a promising therapeutic agent with a diverse range of potential applications. Unlike its well-known counterpart tetrahydrocannabinol (THC), CBG does not induce intoxication, making it an attractive option in the clinic. Recent research has shed light on CBG’s intriguing molecular mechanisms, highlighting its potential to modulate multiple physiological processes. This review delves into the current understanding of CBG’s molecular interactions and explores its therapeutic power to alleviate various conditions, including cancer, metabolic, pain, and inflammatory disorders, amongst others. We discuss how CBG interacts with the endocannabinoid system and other key signaling pathways, such as CB1, CB2, TPR channels, and α2-adrenoceptor, potentially influencing inflammation, pain, neurodegeneration, and other ailments. Additionally, we highlight the ongoing research efforts aimed at elucidating the full spectrum of CBG’s therapeutic potential and its safety profile in clinical settings. Through this comprehensive analysis, we aim to provide a deeper understanding of CBG’s role in promoting human health and pave the way for future research endeavors. Full article

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4 pages, 180 KiB

Open AccessEditorial

Wastewater Treatments Based on Adsorption, Catalysis, Biodegradation, and Beyond

by Dimitrios A. Giannakoudakis and Yongchang Sun

Molecules 2024, 29(22), 5470; https://doi.org/10.3390/molecules29225470 - 20 Nov 2024

Viewed by 257

Abstract

The ongoing technological advancements and industrial growth over the past few decades have resulted in significant environmental challenges, with one of the most notable being water pollution caused by the improper disposal of organic and inorganic pollutants [...] Full article

(This article belongs to the Special Issue Wastewater Treatments Based on Adsorption, Catalysis, Biodegradation, and Beyond)

19 pages, 3701 KiB

Open AccessArticle

Enhancing Antileishmanial Activity of Amidoxime-Based Compounds Bearing a 4,5-Dihydrofuran Scaffold: In Vitro Screening Against Leishmania amazonensis

by Fabiana Maia Santos Urbancg Moncorvo, Oscar Leonardo Avendaño Leon, Christophe Curti, Youssef Kabri, Sébastien Redon, Eduardo Caio Torres-Santos and Patrice Vanelle

Molecules 2024, 29(22), 5469; https://doi.org/10.3390/molecules29225469 - 20 Nov 2024

Viewed by 292

Abstract

Leishmaniasis, a protozoan disease affecting humans, exposes significant shortcomings in current treatments. In continuation to our previous findings on amidoxime-based antileishmanial compounds bearing a 4,5-dihydrofuran scaffold, twelve new amidoxime derivatives substituted at position 3 with an amide bearing a nitrogen heterocycle were synthesized. [...] Read more.

Leishmaniasis, a protozoan disease affecting humans, exposes significant shortcomings in current treatments. In continuation to our previous findings on amidoxime-based antileishmanial compounds bearing a 4,5-dihydrofuran scaffold, twelve new amidoxime derivatives substituted at position 3 with an amide bearing a nitrogen heterocycle were synthesized. This series was designed to replace the sulfone and aryl group on a previously reported HIT. The synthesis of these compounds involved the following three-step pathway: manganese (III) acetate-based cyclization of a β-ketoester, followed by amidation with LiHMDS and a final reaction with hydroxylamine. Three of them, containing either bromine, chlorine, or methyl substitutions and featuring a pyridine moiety, showed an interesting toxicity–activity relationship in vitro. They exhibited IC₅₀ values of 15.0 µM, 16.0 µM, and 17.0 µM against the promastigote form of the parasite and IC₅₀ values of 0.5 µM, 0.6 µM, and 0.3 µM against the intracellular amastigote form, respectively. A selectivity index (SI) greater than 300 was established between the cytotoxic concentrations (in murine macrophages) and the effective concentrations (against the intracellular form of Leishmania amazonensis). This SI is at least seventy times higher than that observed for Pentamidine and twenty-five times higher than that observed for the reference HIT, as previously reported. Full article

(This article belongs to the Special Issue Organic Synthesis and Medicinal Chemistry, Two Inseparable Partners: Recent Advances in Heterocyclic Chemistry)

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15 pages, 4604 KiB

Open AccessArticle

Development of an Electrochemical Paper-Based Device Modified with Functionalized Biochar for the Screening of Paracetamol in Substandard Medicines

by Martin Kassio Leme da Silva, Francisco Contini Barreto, Guilherme dos Santos Sousa, Rafael Plana Simões, Gaurav Ahuja, Samriddha Dutta, Ashok Mulchandani and Ivana Cesarino

Molecules 2024, 29(22), 5468; https://doi.org/10.3390/molecules29225468 - 20 Nov 2024

Viewed by 372

Abstract

The global prevalence of counterfeit and low-quality pharmaceuticals poses significant health risks and challenges in medical treatments, creating a need for rapid and reliable drug screening technologies. This study introduces a cost-effective electrochemical paper-based device (ePAD) modified with functionalized bamboo-derived biochar (BCF) for [...] Read more.

The global prevalence of counterfeit and low-quality pharmaceuticals poses significant health risks and challenges in medical treatments, creating a need for rapid and reliable drug screening technologies. This study introduces a cost-effective electrochemical paper-based device (ePAD) modified with functionalized bamboo-derived biochar (BCF) for the detection of paracetamol in substandard medicines. The sensor was fabricated using a custom 3D-printed stencil in PLA, designed for efficient production, and a 60:40 (m/m) graphite (GR) and glass varnish (GV) conductive ink, resulting in a robust and sensitive platform. The electroactive area of the ePAD/BCF sensor was determined as 0.37 cm². Characterization via SEM and cyclic voltammetry (CV) verified its structural and electrochemical stability. The sensor demonstrated linear detection of paracetamol from 5.0 to 60.0 µmol L⁻¹ with a detection limit of 3.50 µmol L⁻¹. Interference studies showed high selectivity, with recoveries of over 90%, and the sensor successfully quantified paracetamol in commercial analgesic and anti-flu samples. This sustainable, bamboo-based ePAD offers a promising solution for rapid on-site pharmaceutical quality control, with significant potential to enhance drug screening accuracy. Full article

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20 pages, 4002 KiB

Open AccessArticle

Valsartan/2-Aminopyridine Co-Amorphous System: Preparation, Characterization, and Supramolecular Structure Simulation by Density Functional Theory Calculation

by Linjie Wang, Chunan Du, Yang Yang, Pengtu Zhang and Shiling Yuan

Molecules 2024, 29(22), 5467; https://doi.org/10.3390/molecules29225467 - 20 Nov 2024

Viewed by 280

Abstract

The objective of this work was to improve the solubility and discover a stable co-amorphous form of valsartan (VAL), a BCS class-II drug, by utilizing small molecule 2-Aminopyridine (2-AP) in varying molar ratios (2:1, 1:1, and 1:2), employing a solvent evaporation technique. Additionally, [...] Read more.

The objective of this work was to improve the solubility and discover a stable co-amorphous form of valsartan (VAL), a BCS class-II drug, by utilizing small molecule 2-Aminopyridine (2-AP) in varying molar ratios (2:1, 1:1, and 1:2), employing a solvent evaporation technique. Additionally, by way of a density functional theory (DFT)-based computational method with commercially available software, a new approach for determining the intermolecular connectivity of multi-molecular hydrogen bonding systems was proposed. The binary systems’ features were characterized by PXRD, DSC, FTIR, and Raman spectroscopy, while the equilibrium solubility and dissolution was determined in 0.1 N HCL and water conditions to investigate the dissolution advantage of the prepared co-amorphous systems. The results demonstrated that the co-amorphous system was successfully prepared in VAL/2-AP with a 1:2 molar ratio following solvent evaporation, whereby the hydrogen bonding sites of VAL were fully occupied. Physical stability studies were carried out under dry conditions at room temperature for 6 months. Furthermore, four possible ternary systems were constructed, and their vibrational modes were simulated by DFT calculations. The calculated infrared spectra of the four configurations varied widely, with trimer 1 showing the most resemblance to the experimental spectrum of the co-amorphous 1:2 system. Additionally, co-amorphous VAL/2-AP displayed significant improvement in the solubility and dissolution study. Notably, in the 1:2 ratio, there was almost a 4.5-fold and 15.6-fold increase in VAL’s solubility in 0.1 N HCL and water environments, respectively. In conclusion, our findings highlight the potential of co-amorphous systems as a feasible approach to improving the properties and bioavailabilities of insoluble drugs. The proposed simulation method provides valuable insights into determining the supramolecular structure of multi-molecular hydrogen bonding systems, offering a novel perspective for investigating such systems. Full article

(This article belongs to the Special Issue Molecular Simulation in Interface and Surfactant—2nd Edition)

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20 pages, 4448 KiB

Open AccessArticle

Precision Synthesis of Conjugated Polymer Films by Surface-Confined Stepwise Sonogashira Cross-Coupling

by Sang Gil Youm, Mitchell T. Howell, Chien-Hung Chiang, Lu Lu, Neepa M. K. Kuruppu Arachchige, John F. Ankner, Joseph Strzalka, Yaroslav Losovyj, Jayne C. Garno and Evgueni E. Nesterov

Molecules 2024, 29(22), 5466; https://doi.org/10.3390/molecules29225466 - 20 Nov 2024

Viewed by 324

Abstract

Thin films of poly(arylene ethynylene)-conjugated polymers, including low-energy-gap donor–acceptor polymers, can be prepared via stepwise polymerization utilizing surface-confined Sonogashira cross-coupling. This robust and efficient polymerization protocol yields conjugated polymers with a precise molecular structure and with nanometer-level control of the organization and the [...] Read more.

Thin films of poly(arylene ethynylene)-conjugated polymers, including low-energy-gap donor–acceptor polymers, can be prepared via stepwise polymerization utilizing surface-confined Sonogashira cross-coupling. This robust and efficient polymerization protocol yields conjugated polymers with a precise molecular structure and with nanometer-level control of the organization and the uniform alignment of the macromolecular chains in the densely packed film. In addition to high stability and predictable and well-defined molecular organization and morphology, the surface-confined conjugated polymer chains experience significant interchain electronic interactions, resulting in dominating intermolecular π-electron delocalization which is primarily responsible for the electronic and spectroscopic properties of polymer films. The fluorescent films demonstrate remarkable performance in chemosensing applications, showing a turn-off fluorescent response on the sub-ppt (part per trillion) level of nitroaromatic explosives in water. This unique sensitivity is likely related to the enhanced exciton mobility in the uniformly aligned and structurally monodisperse polymer films. Full article

(This article belongs to the Special Issue Recent Developments in Cross-Coupling Reactions)

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18 pages, 3259 KiB

Open AccessArticle

Comparative Metabolomic Analysis and Antinociceptive Effect of Methanolic Extracts from Salvia cinnabarina, Salvia lavanduloides and Salvia longispicata

by Nancy Ortiz-Mendoza, Juan L. Monribot-Villanueva, José A. Guerrero-Analco, Martha J. Martínez-Gordillo, Francisco A. Basurto-Peña, Eva Aguirre-Hernandez and Marcos Soto-Hernández

Molecules 2024, 29(22), 5465; https://doi.org/10.3390/molecules29225465 - 20 Nov 2024

Viewed by 503

Abstract

Mexico is considered one of the countries with the greatest diversity of the Salvia genus. A significant percentage of its species are known for their use in traditional medicine, highlighting their use as an analgesic. The objective of this work was to determine [...] Read more.

Mexico is considered one of the countries with the greatest diversity of the Salvia genus. A significant percentage of its species are known for their use in traditional medicine, highlighting their use as an analgesic. The objective of this work was to determine the chemical composition of the methanolic extracts of S. cinnabarina, S. lavanduloides and S. longispicata through untargeted metabolomics, as well as the in vivo evaluation of the antinociceptive effect and acute oral toxicity. The chemical profiling was performed using ultra-high performance liquid chromatography coupled with a high-resolution mass spectrometry (UPLC-ESI^+/−-MS-QTOF) system and tentative identifications were performed using a compendium of information on compounds previously isolated from Mexican species of the genus. Pharmacological evaluation was carried out using the formalin test and OECD guidelines. The analysis of the spectrometric features of the mass/charge ratios of the three salvias shows that a low percentage of similarity is shared between them. Likewise, the putative identification allowed the annotation of 46 compounds, mainly of diterpene and phenolic nature, with only four compounds shared between the three species. Additionally, the extracts of the three salvias produced a significant antinociceptive effect at a dose of 300 mg/kg administered orally and did not present an acute oral toxicity effect at the maximum dose tested, indicating a parameter of LD₅₀ > 2000 mg/kg. The exploration of the chemical profile of the three salvias by untargeted metabolomics shows that, despite being species with antinociceptive potential, they have different chemical profiles and therefore different active metabolites. Full article

(This article belongs to the Special Issue Chemical Profiling of Plant Extracts with Antioxidant Activity: Identification of Bioactive Compounds)

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14 pages, 433 KiB

Open AccessArticle

Effect of Various Thermal Processing Methods on the Sensory, Textural, and Physicochemical Characteristics of Foal Meat

by Renata Stanisławczyk, Jagoda Żurek, Mariusz Rudy, Marian Gil, Anna Krajewska and Dariusz Dziki

Molecules 2024, 29(22), 5464; https://doi.org/10.3390/molecules29225464 - 20 Nov 2024

Viewed by 321

Abstract

Previous research on the impact of various heat treatment methods on meat has primarily focused on conventional meats from common livestock animals, with limited studies on the effects of different heat treatments on foal meat. The aim of this study was to evaluate [...] Read more.

Previous research on the impact of various heat treatment methods on meat has primarily focused on conventional meats from common livestock animals, with limited studies on the effects of different heat treatments on foal meat. The aim of this study was to evaluate how different heat treatments, including sous-vide, affect the sensory, textural, and physicochemical characteristics of foal meat. This allowed for the identification of the most effective heat treatment method to preserve the optimal quality attributes of foal meat while enhancing sensory and textural qualities preferred by consumers. Samples of m. longissimus thoracis were subjected to traditional cooking in two variants: in water at 100 °C in a foil bag for 1.5 h, and cooked to a core temperature of 85 °C (16 half-carcasses × 2 traditional heat treatment methods = 32 samples). Additionally, m. longissimus thoracis was subjected to sous-vide at 55 °C and 65 °C for 4 and 24 h (16 half-carcasses × 2 temperature settings × 2 time settings = 64 samples). Chemical composition, physicochemical properties, color parameters, hem pigment levels, texture characteristics, and sensory properties were analyzed. Compared to sous-vide samples, traditionally cooked foal meat exhibited higher weight loss (p = 0.002), higher fat content (p = 0.003), and lower water content (p = 0.03). Significant improvements in tenderness were observed in sous-vide samples, with the lowest shear force values (52.86 N/cm² at 55 °C and 48.39 N/cm² at 65 °C; p = 0.001) and meat hardness (102.44 N and 101.27 N, respectively; p = 0.015) after 24 h of thermal processing. Moreover, sous-vide cooking significantly improved sensory properties of foal meat, particularly juiciness (p = 0.002), tenderness (p = 0.002), and flavor desirability (p = 0.03), which were highly rated by consumers. Full article

(This article belongs to the Special Issue Nutritional Properties, Sensory Profile and Bioactive Components of Food, 2nd Edition)

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18 pages, 5193 KiB

Open AccessArticle

Single-Component Starch-Based Hydrogels for Therapeutic Delivery

by Alfio Pulvirenti, Antonella Caterina Boccia, Carolina Constantin, Mihaela Surcel, Adriana Munteanu, Victor-Eduard Peteu and Monica Neagu

Molecules 2024, 29(22), 5463; https://doi.org/10.3390/molecules29225463 - 20 Nov 2024

Viewed by 690

Abstract

Hydrogels are interesting materials as delivery systems of various therapeutic agents, mainly due to the water-swollen network and the localized and sustained drug release. Herein, single-component starch-based hydrogels with enhanced degradation rates were produced by applying a facile synthesis and proposed for a [...] Read more.

Hydrogels are interesting materials as delivery systems of various therapeutic agents, mainly due to the water-swollen network and the localized and sustained drug release. Herein, single-component starch-based hydrogels with enhanced degradation rates were produced by applying a facile synthesis and proposed for a novel delivery system of therapeutic molecules. Starch was oxidized with sodium periodate in water and mild conditions to generate aldehyde derivatives that, after a freeze-thaw procedure, were allowed to compact and stable hydrogels. Oxidized starch was also cross-linked with asparagine through a Schiff base reaction to link the active molecule directly to the polysaccharide structure. The materials were structurally and morphologically characterized, and the ability to adsorb and release over time an active molecule was proven by qNMR spectroscopy. The cytotoxicity was evaluated on CAL-27 cell line (oral squamous cell carcinoma). Results indicated that synthesized hydrogels lead to a “frozen proliferative” state on cells due to the swelling capability in the cell medium. This behavior was confirmed by flow cytometry data indicating the hydrogels induced less “early apoptosis” and more “late apoptosis” in the cells, compared to the untreated control. Since the proposed materials are able to control the cell proliferation, they could open a new scenario within the field of precise therapeutic applications. Full article

(This article belongs to the Special Issue Biomedical Hydrogels: Synthesis, Design and Applications (2nd Edition))

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10 pages, 7988 KiB

Open AccessCommunication

Synthesis and Enhanced Electrocatalytic Activity of Platinum and Palladium-Based Nanoflowers Supported on Reduced Graphene Oxide

by Jiefa Shen, Ruigang Xie, Sai Zhang, Daixiang Chen, Shenghu Yan, Lingli Zhou and Jiayin Wang

Molecules 2024, 29(22), 5462; https://doi.org/10.3390/molecules29225462 - 20 Nov 2024

Viewed by 486

Abstract

Graphene-supported flower-shaped platinum and palladium nanomaterials assisted by hexadecyltrimethylammonium bromide have been successfully developed. Compared with the catalyst reduced by the redox reaction between metal precursors and graphene oxide, the flower-shaped catalyst obtained using reduction in active hydrogen atoms exhibits enhanced catalytic activity [...] Read more.

Graphene-supported flower-shaped platinum and palladium nanomaterials assisted by hexadecyltrimethylammonium bromide have been successfully developed. Compared with the catalyst reduced by the redox reaction between metal precursors and graphene oxide, the flower-shaped catalyst obtained using reduction in active hydrogen atoms exhibits enhanced catalytic activity in alcohol electrocatalytic oxidation reactions. Repeated cyclic voltammetry and chronoamperometry tests both indicate that the prepared catalyst has excellent stability. Full article

(This article belongs to the Section Electrochemistry)

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15 pages, 7696 KiB

Open AccessArticle

A Soothing Lavender-Scented Electrospun Fibrous Eye Mask

by Dandan Kang, Yichong Li, Xiaowen Dai, Zixiong Li, Kai Cheng, Wenliang Song and Deng-Guang Yu

Molecules 2024, 29(22), 5461; https://doi.org/10.3390/molecules29225461 - 19 Nov 2024

Viewed by 282

Abstract

Electrospinning technology has demonstrated extensive applications in biomedical engineering, energy storage, and environmental remediation. However, its utilization in the cosmetic industry remains relatively underexplored. To address the challenges associated with skin damage caused by preservatives and thickeners used for extending the shelf life [...] Read more.

Electrospinning technology has demonstrated extensive applications in biomedical engineering, energy storage, and environmental remediation. However, its utilization in the cosmetic industry remains relatively underexplored. To address the challenges associated with skin damage caused by preservatives and thickeners used for extending the shelf life of conventional products, a soothing lavender-scented electrospun fibrous eye mask with coaxial layers was developed using the electrospinning technique. Polyvinyl alcohol (PVA) served as the hydrophilic outer sheath, while polycaprolactone (PCL) constituted the hydrophobic core, with lavender oil (LO) encapsulated within. The structural and physicochemical properties of the samples were characterized using a scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and contact angle measurements. Upon hydration, the fibrous membrane exhibited strong adhesion properties, notable antioxidant activity, and a degree of antibacterial efficacy, demonstrating its potential for safe and effective use in skincare and eye mask applications. These findings suggest that the developed electrospun material offers promising functional properties and functional properties for integration into cosmetic formulations. Full article

(This article belongs to the Special Issue Preparation, Characterization, and Application of Electrospun Nanofibers)

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15 pages, 325 KiB

Open AccessReview

Oxidative Imbalance in Psoriasis with an Emphasis on Psoriatic Arthritis: Therapeutic Antioxidant Targets

by Rafał Bilski, Daria Kupczyk and Alina Woźniak

Molecules 2024, 29(22), 5460; https://doi.org/10.3390/molecules29225460 - 19 Nov 2024

Viewed by 305

Abstract

Psoriasis and psoriatic arthritis (PsA) are chronic autoimmune diseases characterized by persistent inflammation and oxidative imbalance. Oxidative stress, caused by excessive production of reactive oxygen species (ROS) and dysfunction in antioxidant mechanisms, plays a critical role in the pathogenesis of both conditions, leading [...] Read more.

Psoriasis and psoriatic arthritis (PsA) are chronic autoimmune diseases characterized by persistent inflammation and oxidative imbalance. Oxidative stress, caused by excessive production of reactive oxygen species (ROS) and dysfunction in antioxidant mechanisms, plays a critical role in the pathogenesis of both conditions, leading to increased inflammatory processes and tissue damage. This study aims to review current antioxidant-based therapeutic options and analyze oxidative stress biomarkers in the context of psoriasis and PsA. Based on available literature, key biomarkers, such as malondialdehyde (MDA), advanced glycation end-products (AGEs), and advanced oxidation protein products (AOPP), were identified as being elevated in patients with psoriasis and PsA. Conversely, antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), showed reduced activity, correlating with symptom severity. The study also examines the efficacy of various antioxidant therapies, including curcumin, resveratrol, coenzyme Q10, and vitamins C and E, which may aid in reducing oxidative stress and alleviating inflammation. The findings indicated that antioxidants can play a significant role in alleviating symptoms and slowing the progression of psoriasis and PsA through modulation of redox mechanisms and reduction of ROS levels. Antioxidant-based therapies offer a promising direction in treating autoimmune diseases, highlighting the need for further research on their efficacy and potential clinical application. Full article

11 pages, 2290 KiB

Open AccessArticle

Highly Efficient Reduction of Cr (VI) with C₄H₆O₆

by Hao Peng, Zonghui Qin, Guixuan Jin, Jingjing Wang, Jielin Qin, Lihua Ao and Bing Li

Molecules 2024, 29(22), 5459; https://doi.org/10.3390/molecules29225459 - 19 Nov 2024

Viewed by 209

Abstract

In this paper, tartaric acid (C₄H₆O₆) was used as a reductant to treat chromium (VI)-containing solution. Several independent experimental parameters, including reaction temperature, concentration of H₂SO₄, concentration of C₄H₆O [...] Read more.

In this paper, tartaric acid (C₄H₆O₆) was used as a reductant to treat chromium (VI)-containing solution. Several independent experimental parameters, including reaction temperature, concentration of H₂SO₄, concentration of C₄H₆O₆ and reaction time, on the reduction process were studied. The results showed that 100% of the Cr (VI) could be reduced by C₄H₆O₆ in a strong acidic environment under a high reaction temperature. All of the experimental parameters showed positive effects on the reduction process and followed the order [H₂SO₄] > [C₄H₆O₆] > reaction temperature > reaction time. A higher concentration of tartaric acid and higher reaction temperature could facilitate the reduction process and reduce reaction time. Full article

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16 pages, 6760 KiB

Open AccessReview

Recent Developments in the Metal-Catalyzed Synthesis of Nitrogenous Heterocyclic Compounds

by Xueguo Zhang, Wenxuan Bi, Zhenyu Cao, Jian Shen and Baohua Chen

Molecules 2024, 29(22), 5458; https://doi.org/10.3390/molecules29225458 - 19 Nov 2024

Viewed by 303

Abstract

Metal-catalyzed cyclization reactions have become a powerful and efficient approach for the stereoselective construction of both carbocyclic and heterocyclic ring systems. Transition metal complexes, with their ability to activate and selectively functionalize organic substrates, have revolutionized various areas of synthetic chemistry. This review [...] Read more.

Metal-catalyzed cyclization reactions have become a powerful and efficient approach for the stereoselective construction of both carbocyclic and heterocyclic ring systems. Transition metal complexes, with their ability to activate and selectively functionalize organic substrates, have revolutionized various areas of synthetic chemistry. This review highlights recent advancements in metal-catalyzed cyclization reactions, especially in the synthesis of nitrogen-containing heterocycles like imidazoles, pyridines, pyrimidines, and indoles. These advancements have significantly impacted fields such as natural product synthesis, pharmaceuticals, functional materials, and organic electronics. Novel catalytic systems, ligand designs, and reaction conditions continue to expand the capabilities of these reactions, driving further the progress made in synthetic organic chemistry. This review provides a comprehensive overview of recent research. Full article

(This article belongs to the Special Issue Featured Reviews in Organic Chemistry 2024)

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13 pages, 1232 KiB

Open AccessArticle

Towards a General Method for Using Cyclotron-Produced Ga68 to Manufacture Clinical and Research Ga68 Tracers

by Ivan E. Wang, Kevin Cheng, Allen F. Brooks, Peter J. H. Scott and Benjamin L. Viglianti

Molecules 2024, 29(22), 5457; https://doi.org/10.3390/molecules29225457 - 19 Nov 2024

Viewed by 438

Abstract

The success of multiple nuclear medicine radiotherapeutics in treating cancer requires an increased supply of companion diagnostic imaging agents radiolabeled with gallium-68. Cyclotron production addresses the need for access to gallium-68 and has been validated for use with commercially produced sterile kits. For [...] Read more.

The success of multiple nuclear medicine radiotherapeutics in treating cancer requires an increased supply of companion diagnostic imaging agents radiolabeled with gallium-68. Cyclotron production addresses the need for access to gallium-68 and has been validated for use with commercially produced sterile kits. For novel research tracers undergoing translational studies (IND or RDRC), developing and purchasing sterile kits is time- and cost-prohibitive. An on-cassette labeling method with terminal filtration allows non-sterile kits to be fabricated in-house, simplifying workflow and allowing multiple PET imaging agents to be evaluated using the same kit (i.e., parts, reagents, and timelist) with minimal variation. Using modified GE gallium chloride cassettes, four diverse clinically relevant tracers (DOTA-TOC, FAPI-04, pentixafor, and PSMA-11) were radiolabeled with gallium-68 to evaluate the approach using DOTA and HBED-CC chelator types. The tracers were all formulated according to established FDA-approved formulations and sterile-filtered using a PVDF membrane. The automated procedure is robust, tolerating DOTA and HBED-CC chelators, and can be used to screen numerous gallium-68 agents for rapid translation to clinical use. Full article

(This article belongs to the Special Issue Featured Papers in Medicinal Chemistry II)

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