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Molecules, Volume 29, Issue 23 (December-1 2024) – 47 articles

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26 pages, 1059 KiB  
Review
Review of the Integrated Approaches for Monitoring and Treating Parabens in Water Matrices
by Denga Ramutshatsha-Makhwedzha and Tshimangadzo S. Munonde
Molecules 2024, 29(23), 5533; https://doi.org/10.3390/molecules29235533 - 22 Nov 2024
Abstract
Due to their antibacterial and antifungal properties, parabens are commonly used as biocides and preservatives in food, cosmetics, and pharmaceuticals. Parabens have been reported to exist in various water matrices at low concentrations, which renders the need for sample preparation before their quantification [...] Read more.
Due to their antibacterial and antifungal properties, parabens are commonly used as biocides and preservatives in food, cosmetics, and pharmaceuticals. Parabens have been reported to exist in various water matrices at low concentrations, which renders the need for sample preparation before their quantification using analytical techniques. Thus, sample preparation methods such as solid-phase extraction (SPE), rotating-disk sorptive extraction (RDSE), and vortex-assisted dispersive liquid–liquid extraction (VA-DLLE) that are commonly used for parabens extraction and preconcentration have been discussed. As a result of sample preparation methods, analytical techniques now detect parabens at trace levels ranging from µg/L to ng/L. These compounds have been detected in water, air, soil, and human tissues. While the full impact of parabens on human health and ecosystems is still being debated in the scientific community, it is widely recognized that parabens can act as endocrine disruptors. Furthermore, some studies have suggested that parabens may have carcinogenic effects. The presence of parabens in the environment is primarily due to wastewater discharges, which result in widespread contamination and their concentrations increased during the COVID-19 pandemic waves. Neglecting the presence of parabens in water exposes humans to these compounds through contaminated food and drinking water. Although there are reviews that focus on the occurrence, fate, and behavior of parabens in the environment, they frequently overlook critical aspects such as removal methods, policy development, and regulatory frameworks. Addressing this gap, the effective treatment of parabens in water relies on combined approaches that address both cost and operational challenges. Membrane filtration methods, such as nanofiltration (NF) and reverse osmosis (RO), demonstrate high efficacy but are hindered by maintenance and energy costs due to extensive fouling. Innovations in anti-fouling and energy efficiency, coupled with pre-treatment methods like adsorption, help mitigate these costs and enhance scalability. Furthermore, combining adsorption with advanced oxidation processes (AOPs) or biological treatments significantly improves economic and energy efficiency. Integrating systems like O₃/UV with activated carbon, along with byproduct recovery strategies, further advances circular economy goals by minimizing waste and resource use. This review provides a thorough overview of paraben monitoring in wastewater, current treatment techniques, and the regulatory policies that govern their presence. Furthermore, it provides perspectives that are critical for future scientific investigations and shaping policies aimed at mitigating the risks of parabens in drinking water. Full article
16 pages, 1271 KiB  
Article
The Biochar Derived from Pecan Shells for the Removal of Congo Red: The Effects of Temperature and Heating Rate
by Wanqiang Xu, Bo Cai, Xujie Zhang, Yating Zhang, Yongjian Zhang and Hehuan Peng
Molecules 2024, 29(23), 5532; https://doi.org/10.3390/molecules29235532 - 22 Nov 2024
Abstract
Organic pollutants, especially dyes, are seriously hazardous to the aquatic system and humans due to their toxicity, and carcinogenic or mutagenic properties. In this study, a biochar prepared from agricultural waste (pecan shells) via pyrolysis was applied to remove the dye pollutant Congo [...] Read more.
Organic pollutants, especially dyes, are seriously hazardous to the aquatic system and humans due to their toxicity, and carcinogenic or mutagenic properties. In this study, a biochar prepared from agricultural waste (pecan shells) via pyrolysis was applied to remove the dye pollutant Congo Red from wastewater to avoid a negative effect to the ecosystem. This study also investigated the effect of preparation conditions (temperature and heating rate) on the physicochemical properties and the adsorption performance of biochars. The physicochemical properties of the biochar were characterized using scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption performance of the biochar was evaluated for Congo Red removal. The results showed that biochar prepared at 800 °C with a heating rate of 20 °C/min (PSC-800-20) exhibited a higher specific surface area of 450.23 m2/g and a higher adsorption capacity for Congo Red (130.48 mg/g). Furthermore, adsorption experiments indicated that the pseudo-second-order and Langmuir models fitted well with the adsorption kinetics and isotherms of the biochar derived from pecan shells, respectively. Additionally, the PSC-800-20 biochar demonstrated a stable adsorption capacity over multiple cycles, suggesting its potential for regeneration and reuse in wastewater treatment applications. Therefore, the biochar derived from agricultural waste presents a promising and sustainable solution for the removal of toxic dye pollutants from wastewater. Full article
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26 pages, 822 KiB  
Review
Behavior of Silver Species in Soil: Ag Nanoparticles vs. Ionic Ag
by Joanna Kyziol-Komosinska, Agnieszka Dzieniszewska and Justyna Czupioł
Molecules 2024, 29(23), 5531; https://doi.org/10.3390/molecules29235531 - 22 Nov 2024
Abstract
Silver nanoparticles are one of the most commonly used forms of silver (Ag) in nanotechnology applications due to their antibacterial properties and electrical and thermal resistance. The increasing production and use of products containing nanoparticles has led to their release into and contamination [...] Read more.
Silver nanoparticles are one of the most commonly used forms of silver (Ag) in nanotechnology applications due to their antibacterial properties and electrical and thermal resistance. The increasing production and use of products containing nanoparticles has led to their release into and contamination of soil and water. This review summarizes the literature on the fate, behavior (adsorption/desorption, precipitation/oxidative dissolution, transformation), and transport/mobility of Ag forms in soils (Ag+ ions and Ag nanoparticles—AgNPs). The behavior of Ag+/AgNPs in soil is a complex process. It depends on many factors, including the characteristics of the Ag forms (ions, nanoparticle size, ligand type used for coating, surface charge, initial Ag concentration), the soil properties (organic matter and clay mineral content, textural properties, point of zero charge, cation exchange capacity, surface functional groups), and the solute properties (pH–Eh, ionic strength, cation type, oxygen content). The binding of Ag+ and AgNPs is significantly positively correlated with Al/Fe/Mn oxide and SOM content and depends on the surface charge of the minerals and CEC, which controls adsorption processes. Very important parameters to consider are the pH and Eh of the solution, which determine the durability of the ligands, the aggregation rate and the oxidation process of AgNPs, as well as the presence of sulfide and chloride and the Cl/Ag ratio, which determine the stability/mobility of Ag. Since AgNPs can be oxidized to Ag+ ions during their life cycle, it is necessary to consider the behavior of both forms of Ag in soils. Understanding the transport and behavior of Ag in soil is essential for the environmental risk assessment and management of wastes containing Ag. Full article
19 pages, 380 KiB  
Article
Extraction of Bioactive Compounds and Influence of Storage Conditions of Raw Material Chamaenerion angustifolium (L.) Holub Using Different Strategies
by Domantas Armonavičius, Mantas Stankevičius and Audrius Maruška
Molecules 2024, 29(23), 5530; https://doi.org/10.3390/molecules29235530 - 22 Nov 2024
Abstract
The study evaluates different preparation methods for identifying the best strategy for extracting biologically active compounds from raw Chamaenerion angustifolium (L.) Holub plant material. The methodologies include direct aqueous methanol extraction with a combination of natural aerobic and anaerobic fermentation for 24–72 h, [...] Read more.
The study evaluates different preparation methods for identifying the best strategy for extracting biologically active compounds from raw Chamaenerion angustifolium (L.) Holub plant material. The methodologies include direct aqueous methanol extraction with a combination of natural aerobic and anaerobic fermentation for 24–72 h, followed by 35 °C and 60 °C drying. Furthermore, the study also focuses on determining the different temperature storage conditions on the stability of biologically active compounds. UV-VIS spectroscopy was used to quantitatively evaluate the total content of phenolic compounds, flavonoids, and radical scavenging activity. For qualitative analysis, chromatographic separation with electrochemical detection (ED) of extracted compounds, a gradient high-performance liquid chromatography (HPLC) system was used. Study results indicate that 48 h natural aerobic fermentation followed by 35 °C drying and 75% (v/v) aqueous methanol extraction yielded the maximum amount of biologically active compounds in Chamaenerion angustifolium (L.) Holub leaves, blossom, and stem samples. Freezing samples in liquid nitrogen had the lowest impact on the total content of phenolic compounds, flavonoids, and radical scavenging activity. HPLC-ED system results identified chlorogenic acid, oenothein B, trans-p-Coumaric acid, ellagic acid, and rutin in Chamaenerion angustifolium (L.) Holub leave samples. Full article
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19 pages, 1678 KiB  
Article
Evaluation of Quinazolin-2,4-Dione Derivatives as Promising Antibacterial Agents: Synthesis, In Vitro, In Silico ADMET and Molecular Docking Approaches
by Aboubakr H. Abdelmonsef, Mohamed El-Naggar, Amal O. A. Ibrahim, Asmaa S. Abdelgeliel, Ihsan A. Shehadi, Ahmed M. Mosallam and Ahmed Khodairy
Molecules 2024, 29(23), 5529; https://doi.org/10.3390/molecules29235529 - 22 Nov 2024
Abstract
Abstract: A series of new quinazolin-2,4-dione derivatives incorporating amide/eight-membered nitrogen-heterocycles 2a–c, in addition, acylthiourea/amide/dithiolan-4-one and/or phenylthiazolidin-4-one 3a–d and 4a–d. The starting compound 1 was prepared by reaction of 4-(2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)-benzoyl chloride with ammonium [...] Read more.
Abstract: A series of new quinazolin-2,4-dione derivatives incorporating amide/eight-membered nitrogen-heterocycles 2a–c, in addition, acylthiourea/amide/dithiolan-4-one and/or phenylthiazolidin-4-one 3a–d and 4a–d. The starting compound 1 was prepared by reaction of 4-(2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)-benzoyl chloride with ammonium thiocyanate and cyanoacetic acid hydrazide. The reaction of 1 with strong electrophiles, namely, o-aminophenol, o-amino thiophenol, and/or o-phenylene diamine, resulted in corresponding quinazolin-2,4-dione derivatives incorporating eight-membered nitrogen-heterocycles 2a–d. Compounds 3a–d and 4a–d were synthesized in good-to-excellent yield through a one-pot multi-component reaction (MCR) of 1 with carbon disulfide and/or phenyl isocyanate under mild alkaline conditions, followed by ethyl chloroacetate, ethyl iodide, methyl iodide, and/or concentrated HCl, respectively. The obtained products were physicochemically characterized by melting points, elemental analysis, and spectroscopic techniques, such as FT-IR, 1H-NMR, 13C-NMR, and MS. The antibacterial efficacy of the obtained eleven molecules was examined in vitro against two Gram-positive bacterial strains (Staphylococcus aureus and Staphylococcus haemolyticus). Furthermore, Computer-Aided Drug Design (CADD) was performed on the synthesized derivatives, standard drug (Methotrexate), and reported antibacterial drug with the target enzymes of bacterial strains (S. aureus and S. haemolyticus) to explain their binding mode of actions. Notably, our findings highlight compounds 2b and 2c as showing both the best antibacterial activity and docking scores against the targets. Finally, according to ADMET predictions, compounds 2b and 2c possessed acceptable pharmacokinetics properties and drug-likeness properties. Full article
(This article belongs to the Section Organic Chemistry)
23 pages, 2873 KiB  
Article
Effect of Different Colours of Light on Chosen Aspects of Metabolism of Radish Sprouts with Phosphoromic Approach
by Anna Kafka, Jacek Lipok, Beata Żyszka-Haberecht and Dorota Wieczorek
Molecules 2024, 29(23), 5528; https://doi.org/10.3390/molecules29235528 - 22 Nov 2024
Abstract
Among various environmental factors, light is a crucial parameter necessary for the germination of some seeds. Seed germination is an important phase in the plant life cycle, when metabolic activity is resumed and reserves are mobilized to support initial plant development. Although all [...] Read more.
Among various environmental factors, light is a crucial parameter necessary for the germination of some seeds. Seed germination is an important phase in the plant life cycle, when metabolic activity is resumed and reserves are mobilized to support initial plant development. Although all nutrients are extremely important for proper physiological and biochemical development of plants, phosphorus (P) seems to play a special role, as it is an essential component of all important structural and functional substances which compose the cells of plants. We believe that transformations of the forms of phosphorus accompanying metabolic activity of germinating seeds determine the efficiency of this process, and thus the seedling’s metabolic status. Therefore, we decided to study the changes in the major phosphorus-containing substances in radish sprouts during the first phase of growth. The effect of different colours of light on the quality parameters in radish, as a model plant, during germination, was evaluated. Contents of Pi, adenylates, antioxidants, pigments, phytase activity, and 31P NMR phosphorus profile were investigated. Based on the results of our study, we may propose the phosphoromic approach as an important metabolic parameter determining the physiological status of the plant. Full article
(This article belongs to the Section Applied Chemistry)
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18 pages, 5118 KiB  
Article
Thermooxidation of Four Sartans: Kinetic Analysis Based on Thermo-Gravimetric Data
by Adriana Ledeţi, Bianca Baul, Amalia Ridichie, Denisa Ivan, Titus Vlase, Carmen Tomoroga, Anca Dragomirescu, Gabriela Vlase, Răzvan Adrian Bertici, Dana Emilia Man and Ionuţ Ledeţi
Molecules 2024, 29(23), 5527; https://doi.org/10.3390/molecules29235527 - 22 Nov 2024
Abstract
Angiotensin II receptor antagonists are tetrazole derivatives used in the treatment of high blood pressure, and are also indicated for the treatment of heart failure (NYHA class II-IV). They are used alone or in combination with other classes of antihypertensives or diuretics for [...] Read more.
Angiotensin II receptor antagonists are tetrazole derivatives used in the treatment of high blood pressure, and are also indicated for the treatment of heart failure (NYHA class II-IV). They are used alone or in combination with other classes of antihypertensives or diuretics for the effective management of high blood pressure. In this study, we aim to evaluate the thermal stability and degradation kinetics for the principal compounds used in therapy from this class, namely telmisartan, valsartan, olmesartan medoxomil, and losartan potassium. To obtain the thermoanalytical data for the kinetic investigations, the TG and DTG curves were registered at five different heating rates (β = 2, 4, 6, 8, and 10 °C min−1). The kinetic methods used were a preliminary ASTM E698 method and two isoconversional methods: Flynn–Wall–Ozawa and Friedman. For each molecule, the results showed complex decomposition processes consisting of complex reaction sequences. Full article
(This article belongs to the Special Issue Advances in Pharmaceutical Analytical Technologies)
29 pages, 2199 KiB  
Article
Development of Naphthalene-Derivative Bis-QACs as Potent Antimicrobials: Unraveling Structure–Activity Relationship and Microbiological Properties
by Nikita A. Frolov, Mary A. Seferyan, Elena V. Detusheva, Elizabeth Son, Ilya G. Kolmakov, Alena S. Kartseva, Victoria V. Firstova, Anatoly N. Vereshchagin and Michail N. Elinson
Molecules 2024, 29(23), 5526; https://doi.org/10.3390/molecules29235526 - 22 Nov 2024
Abstract
While the pandemic is behind us, the world community faces a global threat of bacterial resistance outbreak. One of the key ways to combat the spread of multi-resistant bacteria is infection prevention and control tactics using modern antiseptic and disinfectant compositions. Herein, we [...] Read more.
While the pandemic is behind us, the world community faces a global threat of bacterial resistance outbreak. One of the key ways to combat the spread of multi-resistant bacteria is infection prevention and control tactics using modern antiseptic and disinfectant compositions. Herein, we continue the path to unravel the structure–activity relationship (SAR) of potent pyridine-derived biocide class bis-quaternary ammonium compounds (QACs). In this study, twenty dihydroxynaphthalene-derivative bis-QACs were subjected to extensive microbiological analysis on planktonic cells and biofilms of the ESKAPE microorganisms. Among them, hit compounds were superior in their bacteriostatic and bactericidal action to commercial mono-QACs and were comparable to the best bis-QAC antiseptic on the market. SAR analysis indicated that the linker conformation does not significantly affect the activity, though structure symmetry and especially lipophilicity had an influence on antibacterial performance. Furthermore, we delve deeper in investigation of the antimicrobial potential of bis-QACs and conducted a variety of assays, including time–kill kinetics, bacterial resistance formation, cell morphology, and cytotoxicity. Studies showed promising results for compounds 5d and 6d, indicating 2 to 3-fold less cytotoxicity and hemotoxicity compared to commercial QACs. Moreover, SEM imaging revealed that bis-QACs can cause severe membrane damage to S. aureus and P. aeruginosa strains, confirming great potential of novel compounds as antiseptic and disinfectant. Full article
35 pages, 989 KiB  
Review
Diversity of Microglia-Derived Molecules with Neurotrophic Properties That Support Neurons in the Central Nervous System and Other Tissues
by Kennedy R. Wiens, Naved Wasti, Omar Orlando Ulloa and Andis Klegeris
Molecules 2024, 29(23), 5525; https://doi.org/10.3390/molecules29235525 - 22 Nov 2024
Abstract
Microglia, the brain immune cells, support neurons by producing several established neurotrophic molecules including glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Modern analytical techniques have identified numerous phenotypic states of microglia, each associated with the secretion of a diverse [...] Read more.
Microglia, the brain immune cells, support neurons by producing several established neurotrophic molecules including glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Modern analytical techniques have identified numerous phenotypic states of microglia, each associated with the secretion of a diverse set of substances, which likely include not only canonical neurotrophic factors but also other less-studied molecules that can interact with neurons and provide trophic support. In this review, we consider the following eight such candidate cytokines: oncostatin M (OSM), leukemia inhibitory factor (LIF), activin A, colony-stimulating factor (CSF)-1, interleukin (IL)-34, growth/differentiation factor (GDF)-15, fibroblast growth factor (FGF)-2, and insulin-like growth factor (IGF)-2. The available literature provides sufficient evidence demonstrating murine cells produce these cytokines and that they exhibit neurotrophic activity in at least one neuronal model. Several distinct types of neurotrophic activity are identified that only partially overlap among the cytokines considered, reflecting either their distinct intrinsic properties or lack of comprehensive studies covering the full spectrum of neurotrophic effects. The scarcity of human-specific studies is another significant knowledge gap revealed by this review. Further studies on these potential microglia-derived neurotrophic factors are warranted since they may be used as targeted treatments for diverse neurological disorders. Full article
(This article belongs to the Section Medicinal Chemistry)
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18 pages, 2202 KiB  
Article
Osmotic Dehydration of Japanese Quince (Chaenomeles japonica) Fruits in Erythritol Solutions: Impact of Processing Conditions on the Kinetic Parameters and on Physicochemical and Antioxidant Properties of the Fruits
by Angelika Wojtyś, Sławomir Pietrzyk, Sylwia Bogacz and Robert Witkowicz
Molecules 2024, 29(23), 5524; https://doi.org/10.3390/molecules29235524 - 22 Nov 2024
Abstract
The present work aimed to evaluate the effectiveness of erythritol as an osmotic agent in the osmotic dehydration (OD) process of Japanese quince fruits and to assess its effects on their physicochemical and antioxidant properties. The efficiency of the OD process was determined [...] Read more.
The present work aimed to evaluate the effectiveness of erythritol as an osmotic agent in the osmotic dehydration (OD) process of Japanese quince fruits and to assess its effects on their physicochemical and antioxidant properties. The efficiency of the OD process was determined by examining its kinetics and comparing the results to those from a sucrose solution. In selected osmotically dehydrated fruits, the following parameters were determined: dry matter content, total acidity, pH, sugar profile, color parameters, total phenolic and flavonoid content, antioxidant activity (DPPH and ABTS assays), and vitamin C content. Moreover, principal component analysis (PCA) was also performed. Generally, the OD process using a 40% erythritol solution demonstrated the most efficient kinetics among all osmotic agents tested; however, fruits dehydrated in this solution also showed the most significant changes in physicochemical and antioxidant properties compared to fresh fruits. Remarkably, Japanese quince fruits dehydrated in a 30% erythritol solution exhibited higher levels of total phenolic, flavonoid, vitamin C, and antioxidant activity than those treated with a 50% sucrose solution, despite displaying similar dehydration kinetics. The use of erythritol solutions also led to a decrease in sugar content. In turn, PCA analysis confirmed a correlation between pH values and the L* color parameter, with the highest L* value observed in fruits dehydrated with the sucrose solution. Thus, erythritol may be utilized as a low-calorie alternative to sucrose as an osmotic agent while simultaneously minimizing the loss of antioxidant compounds. Full article
(This article belongs to the Section Food Chemistry)
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3 pages, 179 KiB  
Editorial
Organosulfur and Organoselenium Chemistry
by Ming Wang
Molecules 2024, 29(23), 5523; https://doi.org/10.3390/molecules29235523 - 22 Nov 2024
Abstract
Organosulfur- and organoselenium-containing compounds play a crucial role in organic synthesis [...] Full article
(This article belongs to the Special Issue Organosulfur and Organoselenium Chemistry)
16 pages, 4694 KiB  
Article
Effects of Ethylene Propylene Diene Monomer (EPDM)-Based Polar Macromolecular Compatibilizers on the Low-Temperature Properties of Fluoroelastomer/EPDM Rubber Blends
by Gen Liu, Faxin Du, Zhangjun Yao, Guangzhao Li, Wen Kuang, Chongyu Zhu, Yi Liu, Honglin Chen, Fumei Wang, Ce Zhou, Xueli Wei, Wenyan Wang and Rui Han
Molecules 2024, 29(23), 5522; https://doi.org/10.3390/molecules29235522 - 22 Nov 2024
Abstract
Integrating rubber with superior low-temperature capabilities, such as ethylene propylene diene monomer (EPDM), is a strategic approach to bolster the low-temperature performance of fluoroelastomer (FKM). However, FKM and EPDM are thermodynamically incompatible. This work synthetized three EPDM-based polar macromolecular compatibilizers, epoxidized EPDM (EPDM-EP), [...] Read more.
Integrating rubber with superior low-temperature capabilities, such as ethylene propylene diene monomer (EPDM), is a strategic approach to bolster the low-temperature performance of fluoroelastomer (FKM). However, FKM and EPDM are thermodynamically incompatible. This work synthetized three EPDM-based polar macromolecular compatibilizers, epoxidized EPDM (EPDM-EP), 2,2-trifluoroethylamine-grafted epoxidized EPDM (EPDM-TF), and 2,4-difluorobenzylamine-grafted epoxidized EPDM (EPDM-DF), to enhance the compatibility between FKM and EPDM. These compatibilizers were subsequently incorporated into FKM/EPDM rubber blends. The results revealed that the glass transition temperature (Tg) of FKM/EPDM decreased by 1.3 °C, 2.68 °C, and 2.78 °C, respectively, upon the addition of 10 phr of EPDM-EP, EPDM-TF, or EPDM-DF. Moreover, the Tg of the two phases converged. The tensile strength, elongation at break, and tear strength of the FKM/EPDM rubber blends were also enhanced by the inclusion of these compatibilizers. Notably, EPDM-TF and EPDM-DF exhibited remarkable compatibilization effects due to an increase in polarity. This research not only sheds light on the potential for developing new compatibilizers but also paves the way for innovative applications of FKM and its derivatives. Full article
(This article belongs to the Section Macromolecular Chemistry)
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15 pages, 4411 KiB  
Article
Spectroscopic and Quantum Chemical Evidence of Amine–CO2 and Alcohol–CO2 Interactions: Confirming an Intriguing Affinity of CO2 to Monoethanolamine (MEA)
by Sahar Hafizi Yazdabadi, Dmytro Mihrin, Karen Louise Feilberg and René Wugt Larsen
Molecules 2024, 29(23), 5521; https://doi.org/10.3390/molecules29235521 - 22 Nov 2024
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Abstract
A recent broadband rotational spectroscopic investigation of the cross-association mechanisms of CO2 with monoethanolamine (MEA) in molecular beams [F. Xie et al., Angew. Chem. Int. Ed., 2023, 62, e202218539] revealed an intriguing affinity of CO2 to the hydroxy [...] Read more.
A recent broadband rotational spectroscopic investigation of the cross-association mechanisms of CO2 with monoethanolamine (MEA) in molecular beams [F. Xie et al., Angew. Chem. Int. Ed., 2023, 62, e202218539] revealed an intriguing affinity of CO2 to the hydroxy group. These findings have triggered the present systematic vibrational spectroscopic exploration of weakly bound amine··CO2 and alcohol··CO2 van der Waals cluster molecules embedded in inert “quantum” matrices of neon at 4.2 K complemented by high-level quantum chemical conformational analyses. The non-covalent interactions formed between the amino and hydroxy groups and the electron-deficient carbon atom of CO2 are demonstrated to lift the degeneracy of the doubly degenerate intramolecular CO2-bending fundamental significantly with characteristic observed spectral splittings for the amine··CO2 (≈35–45 cm−1) and alcohol··CO2 (≈20–25 cm−1) interactions, respectively, despite the almost identically predicted total association energies (≈12–14 kJ·mol−1) for these van der Waals contacts, as revealed by benchmark Domain-based Local Pair Natural Orbital Coupled Cluster DLPNO-CCSD(T) theory. These high-level theoretical predictions reveal significantly higher “geometry preparation energies” for the amine··CO2 systems leading to a more severe distortion of the CO2 linearity upon complexation in agreement with the infrared spectroscopic findings. The systematic combined spectroscopic and quantum chemical evidences for cross-association between CO2 and amines/alcohols in the present work unambiguously confirm an intriguing binding preference of CO2 to the hydroxy group of the important carbon capture agent MEA, with an accurate vibrational zero-point energy corrected association energy (D0) of 13.5 kJ·mol−1 at the benchmark DLPNO-CCSD(T)/aug-cc-pV5Z level of theory. Full article
(This article belongs to the Special Issue Molecular Spectroscopy in Applied Chemistry)
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16 pages, 1275 KiB  
Review
Silver Nanoparticles as a Potent Nanopesticide: Toxic Effects and Action Mechanisms on Pest Insects of Agricultural Importance—A Review
by Daniel Martínez-Cisterna, Olga Rubilar, Gonzalo Tortella, Lingyun Chen, Manuel Chacón-Fuentes, Marcelo Lizama, Pablo Parra and Leonardo Bardehle
Molecules 2024, 29(23), 5520; https://doi.org/10.3390/molecules29235520 - 22 Nov 2024
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Abstract
Nanotechnology has been a promising plant protection discipline in recent years, attributed to the unique physicochemical properties exhibited at the nanoscale. In this context, silver nanoparticles (AgNPs) have been effective in various applications, including medical, industrial, and agronomic, and during the last few [...] Read more.
Nanotechnology has been a promising plant protection discipline in recent years, attributed to the unique physicochemical properties exhibited at the nanoscale. In this context, silver nanoparticles (AgNPs) have been effective in various applications, including medical, industrial, and agronomic, and during the last few years, the control of insect pests has raised great interest. The present review mainly provides updated information about the use of AgNPs elaborated by different synthesis methods, such as biological (plants, microorganisms), physical, and chemical, and their effect against various insect species of agricultural importance belonging to the order Diptera, Coleoptera, Lepidoptera, and Hemiptera. The physiological and toxic effects of applying AgNPs are reported and characterized by developmental problems, mortality, weight reduction, interference with enzymatic activity, and anomalies in the life cycle. Moreover, in the final section, the action mechanisms through which AgNPs act on insects are also discussed, highlighting mechanisms such as alteration of transmembrane permeability, interruption of DNA replication, alteration of protein synthesis, and production of reactive oxygen species (ROS). Full article
(This article belongs to the Special Issue Natural Products as Insecticidal Agents)
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19 pages, 1632 KiB  
Article
New Conjugates of Vancomycin with Cell-Penetrating Peptides—Synthesis, Antimicrobial Activity, Cytotoxicity, and BBB Permeability Studies
by Jarosław Ruczyński, Katarzyna Prochera, Natalia Kaźmierczak, Katarzyna Kosznik-Kwaśnicka, Lidia Piechowicz, Piotr Mucha and Piotr Rekowski
Molecules 2024, 29(23), 5519; https://doi.org/10.3390/molecules29235519 - 22 Nov 2024
Viewed by 76
Abstract
Vancomycin (Van) is a glycopeptide antibiotic commonly used as a last resort for treating life-threatening infections caused by multidrug-resistant bacterial strains, such as Staphylococcus aureus and Enterococcus spp. However, its effectiveness is currently limited due to the rapidly increasing number of drug-resistant clinical [...] Read more.
Vancomycin (Van) is a glycopeptide antibiotic commonly used as a last resort for treating life-threatening infections caused by multidrug-resistant bacterial strains, such as Staphylococcus aureus and Enterococcus spp. However, its effectiveness is currently limited due to the rapidly increasing number of drug-resistant clinical strains and its inherent cytotoxicity and poor penetration into cells and specific regions of the body, such as the brain. One of the most promising strategies to enhance its efficacy appears to be the covalent attachment of cell-penetrating peptides (CPPs) to the Van structure. In this study, a series of vancomycin conjugates with CPPs—such as TP10, Tat (47–57), PTD4, and Arg9—were designed and synthesized. These conjugates were tested for antimicrobial activity against four reference strains (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and two clinical drug-resistant strains: methicillin-resistant S. aureus and vancomycin-resistant E. faecium. In addition, cytotoxicity tests (using a human fibroblast cell line) and blood–brain barrier (BBB) permeability tests (using a parallel artificial membrane permeability assay—PAMPA-BBB assay) were conducted for selected compounds. Our research demonstrated that conjugation of Van with CPPs, particularly with Tat (47–57), Arg9, or TP10, significantly enhances its antimicrobial activity against Gram-positive bacteria such as S. aureus and Enterococcus spp., reduces its cytotoxicity, and improves its access to brain tissues. We conclude that these findings provide a strong foundation for the design of novel antimicrobial agents effective in treating infections caused by drug-resistant staphylococcal and enterococcal strains, while also being capable of crossing the BBB. Full article
(This article belongs to the Special Issue Chemical Biology of Antimicrobial Resistance, 2nd Edition)
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13 pages, 3291 KiB  
Article
Using the Theozyme Model to Study the Dynamical Mechanism of the Post-Transition State Bifurcation Reaction by NgnD Enzyme
by Yaning Hou, Jingyun Chen, Weizhe Liu, Gaohua Zhu, Qianying Yang and Xin Wang
Molecules 2024, 29(23), 5518; https://doi.org/10.3390/molecules29235518 - 22 Nov 2024
Viewed by 134
Abstract
Post-transition state bifurcation (PTSB) is a fundamental process in which a single transition state leads to multiple products. This phenomenon is important in both biological and chemical contexts and offers valuable insights into reaction mechanisms and their applications. The theozyme model, which focuses [...] Read more.
Post-transition state bifurcation (PTSB) is a fundamental process in which a single transition state leads to multiple products. This phenomenon is important in both biological and chemical contexts and offers valuable insights into reaction mechanisms and their applications. The theozyme model, which focuses on key residues within enzymes, offers a computationally efficient method for studying these processes while preserving the enzyme’s catalytic properties. This approach enhances our understanding of how enzymes stabilize and direct the transition state, thereby influencing product distribution and selectivity. In this study, we investigate the dynamics and regulatory mechanisms of the PTSB reaction catalyzed by the enzyme NgnD. The enzyme NgnD facilitates a cycloaddition reaction that produces both [6 + 4] and [4 + 2] adducts, with a preference for the [6 + 4] adduct. By analyzing the potential energy surface, bond length distribution, and interactions between the theozyme and the ambimodal transition state, we elucidate the role of the enzyme’s active site residues in determining product selectivity. We illustrate how these key residues contribute to the formation of different adducts, providing insights from various perspectives. Using theozyme models, we propose how the four most influential active residues collectively might control the direction of adduct formation through their cumulative effects. Full article
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7 pages, 220 KiB  
Brief Report
An Environmentally Compatible and Less Costly (Greener) Microwave Digestion Method of Bone Samples Using Dilute Nitric Acid for Analysis by ICP-MS
by Derek D. Bussan, Forrest H. Nielsen, Chris Douvris, Brett Kelzenberg, Allison Grimestad and Jay J. Cao
Molecules 2024, 29(23), 5517; https://doi.org/10.3390/molecules29235517 - 22 Nov 2024
Viewed by 156
Abstract
An environmentally compatible and less costly (greener) analytical method for the digestion of bone meal samples using microwave-assisted dilute nitric acid (HNO3) was developed and optimized. The method, employing a mixture of 1 mL concentrated HNO3 and 4 mL of [...] Read more.
An environmentally compatible and less costly (greener) analytical method for the digestion of bone meal samples using microwave-assisted dilute nitric acid (HNO3) was developed and optimized. The method, employing a mixture of 1 mL concentrated HNO3 and 4 mL of deionized water, offered a comparable performance to the conventional method using 5 mL of concentrated HNO3. The accuracy of the method was validated by using certified reference material NIST 1486 (Bone Meal); percentage recoveries were within ±15% for all eight certified elements. Statistical analysis revealed no significant differences (p > 0.05) in percentage recoveries between the green and conventional methods for all elements except calcium. The greenness of the developed method was evaluated by using the analytical Eco-Scale, achieving a score of 87, categorizing it as an “excellent green analysis” method. This research highlights the potential for adopting greener practices in trace element analysis that reduce the environmental impact and safety risks associated with concentrated acids. Full article
17 pages, 3095 KiB  
Article
Toxicological Analysis of the Arylnaphthalene Lignan Justicidin B Using a Caenorhabditis elegans Model
by Barbara Sciandrone, Roméo Arago Dougué Kentsop, Roberta Pensotti, Gianluca Ottolina, Iride Mascheretti, Monica Mattana and Maria Elena Regonesi
Molecules 2024, 29(23), 5516; https://doi.org/10.3390/molecules29235516 - 22 Nov 2024
Viewed by 143
Abstract
The screening of plant-derived compounds with anti-cancer properties is a promising strategy to meet the growing need for new, safe and effective anti-cancer drugs. Justicidin B is a plants secondary metabolite that displays anti-cancer properties in several tumor cells. Therefore, it represents a [...] Read more.
The screening of plant-derived compounds with anti-cancer properties is a promising strategy to meet the growing need for new, safe and effective anti-cancer drugs. Justicidin B is a plants secondary metabolite that displays anti-cancer properties in several tumor cells. Therefore, it represents a good candidate. We used the 3R-compliant organism Caenorhabditis elegans to evaluate the safety of justicidin B produced by in vitro-grown adventitious roots of Linum lewisii. We showed that a dose of 100 µg/mL justicidin B does not affect worm vitality in either short-term or chronic administration; in contrast, the 200 µg/mL dose induces a lifespan reduction, but only in short-term daily treatment. We attributed this effect to its accumulation in lipofuscin granules in the pharynx as observed through confocal analysis. HPLC analysis confirmed the higher accumulation justicidin B with a 200 µg/mL dose but also revealed the presence of metabolic derivatives that could be responsible for the toxicity. We also demonstrated that the 100 µg/mL dose does not affect worm fertility or development. Our results highlight the safety of justicidin B, supporting its employment in cancer therapy, and encourage the use of a C. elegans model as an appropriate tool to assess compounds’ toxicity before moving to more complex organisms. Full article
(This article belongs to the Special Issue Research Progress and Application of Natural Compounds—2nd Edition)
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5 pages, 204 KiB  
Editorial
Nano-Functional Materials for Sensor Applications
by Aiwu Wang and Li Fu
Molecules 2024, 29(23), 5515; https://doi.org/10.3390/molecules29235515 - 22 Nov 2024
Viewed by 166
Abstract
The rapid development of nanotechnology and materials science has led to remarkable advances in sensor applications across various fields [...] Full article
(This article belongs to the Special Issue Nano-Functional Materials for Sensor Applications)
17 pages, 4157 KiB  
Article
Laccase Production Optimization from Recombinant E. coli BL21 Codon Plus Containing Novel Laccase Gene from Bacillus megaterium for Removal of Wastewater Textile Dye
by Zannara Mustafa, Ikram ul Haq, Ali Nawaz, Abdulrahman H. Alessa, Muhammad Nauman Aftab, Ahmad A. Alsaigh and Aziz ur Rehman
Molecules 2024, 29(23), 5514; https://doi.org/10.3390/molecules29235514 - 22 Nov 2024
Abstract
The aim of the present research was the efficient degradation of industrial textile wastewater dyes using a very active cloned laccase enzyme. For this purpose, potent laccase-producing bacteria were isolated from soil samples collected from wastewater-replenished textile sites in Punjab, Pakistan. The laccase [...] Read more.
The aim of the present research was the efficient degradation of industrial textile wastewater dyes using a very active cloned laccase enzyme. For this purpose, potent laccase-producing bacteria were isolated from soil samples collected from wastewater-replenished textile sites in Punjab, Pakistan. The laccase gene from locally isolated strain LI-81, identified as Bacillus megaterium, was cloned into vector pET21a, which was further transformed into E. coli BL21 codon plus. The optimized conditions for the increased production of laccase include fermentation in a 2% glucose, 5% yeast extract and 250 mg/L CuSO4 medium with pH 7.5; inoculation with 5% inoculum; induction with 0.1 mM IPTG at 0.5 O.D.; and incubation for 36 h at 37 °C. The crude enzyme produced was employed for the removal of commercially used textile dyes. The dyes were quickly precipitated under optimized reaction conditions. Rose bengal, brilliant green, brilliant blue G, Coomassie brilliant blue R and methylene blue were precipitated at rates of 10.69, 54.47, 84.04, 78.99 and 7.40%, respectively. The FTIR and UV–Vis spectroscopic analyses of dyes before and after confirmed the chemical changes brought about by the cloned laccase that led to the dye removal. Full article
(This article belongs to the Section Chemical Biology)
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11 pages, 1330 KiB  
Article
Simulation Studies of the Dynamics and the Connectivity Patterns of Hydrogen Bonds in Water from Ambient to Supercritical Conditions
by Dorota Swiatla-Wojcik
Molecules 2024, 29(23), 5513; https://doi.org/10.3390/molecules29235513 - 21 Nov 2024
Viewed by 201
Abstract
Pressurized high-temperature water attracts attention as a promising medium for chemical synthesis, biomass processing or destruction of hazardous waste. Adjustment to the desired solvent properties requires knowledge on the behavior of populations of hydrogen-bonded molecules. In this work, the interconnection between the hydrogen [...] Read more.
Pressurized high-temperature water attracts attention as a promising medium for chemical synthesis, biomass processing or destruction of hazardous waste. Adjustment to the desired solvent properties requires knowledge on the behavior of populations of hydrogen-bonded molecules. In this work, the interconnection between the hydrogen bond (HB) dynamics and the structural rearrangements of HB networks have been studied by molecular dynamics simulation using the modified central force flexible potential and the HB definition controlling pair interaction energy, HB length and HB angle. Time autocorrelation functions for molecular pairs bonded continuously and intermittently and the corresponding mean lifetimes have been calculated for conditions ranging from ambient to supercritical. A significant reduction in the continuous and intermittent lifetimes has been found between (293 K, 0.1 MPa) and (373 K, 25 MPa) and attributed to the decreasing size of patches embedded in the continuous HB network. The loss of global HB connectivity at ca. (573 K, 10 MPa) and the investigated supercritical conditions do not noticeably affect the HB dynamics. Over the whole temperature range studied, the reciprocal intermittent lifetime follows the transition state theory dependence on temperature with the activation energy of 10.4 kJ/mol. Calculations of the lifetime of molecules that do not form hydrogen bonds indicate that at supercritical temperatures, the role of reactions involving an unbound H2O molecule as a reactant can be enhanced by lowering system density. Full article
(This article belongs to the Special Issue Computational and Theoretical Insights on Molecular Structure, Solvation, Interactions and New Materials Design)
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19 pages, 1490 KiB  
Article
Generation of Acid Sites in Nanostructured KIT-6 Using Different Methods to Obtain Efficient Acidic Catalysts for Glycerol Acetalization to Solketal
by Ewa Janiszewska, Jolanta Kowalska-Kuś, Justyna Wiktorowska, Aldona Jankowska, Agata Tabero, Agnieszka Held and Stanisław Kowalak
Molecules 2024, 29(23), 5512; https://doi.org/10.3390/molecules29235512 - 21 Nov 2024
Viewed by 163
Abstract
This study explored the preparation of pure silica KIT-6, as well as KIT-6 materials with an enhanced concentration of surface OH groups through aluminum incorporation or NH4F treatment. These materials with various contents of surface OH groups were subsequently modified via [...] Read more.
This study explored the preparation of pure silica KIT-6, as well as KIT-6 materials with an enhanced concentration of surface OH groups through aluminum incorporation or NH4F treatment. These materials with various contents of surface OH groups were subsequently modified via the post-synthesis grafting of sulfonic groups using 3-mercaptopropyltrimethoxysilane as a precursor, followed by oxidation to introduce acidic sites. The catalysts were thoroughly characterized using XRD, nitrogen adsorption/desorption, SEM-EDS, TEM, and FT-IR techniques to confirm their structural and chemical properties. The catalytic activity of acid-functionalized mesoporous silicas of the KIT-6 structure was further evaluated in the acetalization of glycerol to produce solketal. The results demonstrated a significant influence of the surface OH group concentration and acidic site density on catalytic performance, with KIT-6_F_SO3H showing the highest efficiency in glycerol-to-solketal conversion. This study provides valuable insights into the design of efficient catalytic systems for the valorization of biodiesel-derived glycerol into high-value chemicals, offering a sustainable approach to waste glycerol utilization. Full article
(This article belongs to the Special Issue Heterogeneous Catalysts: Synthesis and Application)
17 pages, 4190 KiB  
Article
Oligo(ethylene glycol) Methacrylate Copolymer-Modified Liposomes for Temperature-Responsive Drug Delivery System
by Maria Isabel Martinez Espinoza, Sezen Gül, Luisa Mugnaini and Francesco Cellesi
Molecules 2024, 29(23), 5511; https://doi.org/10.3390/molecules29235511 - 21 Nov 2024
Viewed by 217
Abstract
A thermoresponsive copolymer based on oligo(ethylene glycol) methacrylate, Chol-P(MEO2MA-co-OEGMA), was synthesized using Atom Transfer Radical Polymerization (ATRP) and incorporated into thermosensitive liposomes (TSLs) for controlled drug release. The copolymer exhibited a lower critical solution temperature (LCST) of 37 °C, making it [...] Read more.
A thermoresponsive copolymer based on oligo(ethylene glycol) methacrylate, Chol-P(MEO2MA-co-OEGMA), was synthesized using Atom Transfer Radical Polymerization (ATRP) and incorporated into thermosensitive liposomes (TSLs) for controlled drug release. The copolymer exhibited a lower critical solution temperature (LCST) of 37 °C, making it suitable for biomedical applications requiring precise thermal triggers. The copolymer was incorporated into various TSL formulations alongside phospholipids such as DPPC, Lyso-PC, HSPC, and DSPC. Physicochemical characterization of the liposomes, including average size, polydispersity index, loading efficiency (LE), and encapsulation efficiency (EE), was performed using dynamic light scattering and fluorescence spectroscopy. The results showed that the incorporation of the copolymer slightly affected particle size and decreased LE and EE in most formulations. Lyso-PC-containing formulations exhibited lower LE and EE, likely due to instability during purification. Albumin encapsulation demonstrated lower LE compared to the smaller carboxyfluorescein drug model, highlighting the influence of molecular weight on loading. Although copolymer-modified liposomes showed reduced loading capacity, they enhanced thermoresponsiveness in HSPC-based formulations. These findings suggest that incorporating thermoresponsive polymers into TSLs can optimize drug delivery systems for targeted, thermally triggered release. Full article
(This article belongs to the Special Issue Nanotechnology Applications in Nanomedicine: Recent Advances and Prospects)
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22 pages, 8110 KiB  
Article
Synthesis and Physiochemical Properties of Sulphated Tamarind (Tamarindus indica L.) Seed Polysaccharide
by Sabrina Ziliani, Anna Alekseeva, Carlo Antonini, Emiliano Esposito, Fabio Neggiani, Marco Sansò, Marco Guerrini and Sabrina Bertini
Molecules 2024, 29(23), 5510; https://doi.org/10.3390/molecules29235510 - 21 Nov 2024
Viewed by 244
Abstract
Tamarind seed polysaccharide (TSP) is a neutral water-soluble galactoxyloglucan isolated from the seed kernel of Tamarindus indica with average molecular weight (Mw) 600–800 kDa. The high viscosity of TSP slows solubilisation, and the absence of charged substituent hinders the formation of electrostatic interactions [...] Read more.
Tamarind seed polysaccharide (TSP) is a neutral water-soluble galactoxyloglucan isolated from the seed kernel of Tamarindus indica with average molecular weight (Mw) 600–800 kDa. The high viscosity of TSP slows solubilisation, and the absence of charged substituent hinders the formation of electrostatic interactions with biomolecules. TSP was sulphated in a one-step process using dimethylformamide as a solvent, and sulphur trioxide-pyridine complex as a sulphating reagent. Studies of chemical structure, molecular weight distribution and viscosity were conducted to characterise the synthesised products. The sulphation degree was established by conductimetric titration; the sulphate group distribution was studied by NMR spectroscopy and liquid chromatography-mass spectrometry, and sulphated TSP oligomers were obtained by enzymatic degradation with cellulase and/or xyloglucanase. Sulphated products showed higher solubility than TSP, Mws in the range of 700–1000 kDa, a sulphation degree of two to four per subunit and pseudoplastic behaviour. A preliminary study of mucoadhesion revealed the unexpected interaction of S-TSP with mucin, providing a route by which sulphated TSP interactions with biomolecules may be influenced. Full article
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20 pages, 352 KiB  
Article
The Effect of Osmotic Dehydration Conditions on the Potassium Content in Beetroot (Beta vulgaris L.)
by Bartosz Kulczyński, Joanna Suliburska, Anna Gramza-Michałowska, Andrzej Sidor, Przemysław Łukasz Kowalczewski and Anna Brzozowska
Molecules 2024, 29(23), 5509; https://doi.org/10.3390/molecules29235509 - 21 Nov 2024
Viewed by 230
Abstract
Osmotic dehydration as a process of removing water from food by immersing the raw material in a hypertonic solution is used primarily to extend the shelf life of products and as a pretreatment before further processing steps, such as drying and freezing. However, [...] Read more.
Osmotic dehydration as a process of removing water from food by immersing the raw material in a hypertonic solution is used primarily to extend the shelf life of products and as a pretreatment before further processing steps, such as drying and freezing. However, due to the bi-directional mass transfer that occurs during osmotic dehydration, the process can also be used to shape sensory properties and enrich the plant matrix with nutrients. The purpose of this study was to evaluate the effect of osmotic dehydration on the absorption of potassium by beet pulp immersed in various hypertonic solutions (sucrose, inulin, erythritol, xylitol solutions) with the addition of three chemical forms of potassium (gluconate, citrate, chloride) using variable process conditions. The study proved that osmotic dehydration is an effective way to enrich food. The highest potassium content (5779.03 mg/100 g) was found in a sample osmotically dehydrated in a 50% erythritol solution with 5.0% potassium chloride addition with a process that lasted 180 min and took place at 30 °C. The results obtained indicate the high potential of osmotic dehydration in improving the health values of food products. In addition, the antioxidant activity and proximate composition of osmotically dehydrated samples were also characterized in this study. Full article
(This article belongs to the Special Issue Molecular Level Changes in Food Processing: Invisible Treasures)
18 pages, 9884 KiB  
Article
The Far-Infrared Absorption Spectrum of HD16O: Experimental Line Positions, Accurate Empirical Energy Levels, and a Recommended Line List
by Semen N. Mikhailenko, Ekaterina V. Karlovets, Aleksandra O. Koroleva and Alain Campargue
Molecules 2024, 29(23), 5508; https://doi.org/10.3390/molecules29235508 - 21 Nov 2024
Viewed by 307
Abstract
The far-infrared absorption spectrum of monodeuterated water vapor, HD16O, is analyzed using three high-sensitivity absorption spectra recorded by high-resolution Fourier transform spectroscopy at the SOLEIL synchrotron facility. The gas sample was obtained using a 1:1 mixture of H2O and [...] Read more.
The far-infrared absorption spectrum of monodeuterated water vapor, HD16O, is analyzed using three high-sensitivity absorption spectra recorded by high-resolution Fourier transform spectroscopy at the SOLEIL synchrotron facility. The gas sample was obtained using a 1:1 mixture of H2O and D2O leading to a HDO abundance close to 50%. The room temperature spectra recorded in the 50–720 cm−1 range cover most of the rotational band. The sensitivity of the recordings allows for lowering by three orders of magnitude the detectivity threshold of previous absorption studies in the region. Line centers are determined with a typical accuracy of 5 × 10−5 cm−1 for well-isolated lines. The combined line list of 8522 water lines is assigned to 9186 transitions of the nine stable water isotopologues (H2XO, HDXO, and D2XO with X = 16, 17, and 18). Regarding the HD16O isotopologue, a total of 2443 transitions are presently assigned while about 530 absorption transitions were available prior to our SOLEIL recordings. The comparison with the HITRAN list of HD16O transitions is discussed in detail. The obtained set of accurate HD16O transition frequencies is merged with literature sources to generate a set of 1121 accurate empirical rotation–vibration energies for the first five vibrational states (000), (010), (100), (020), and (001). The comparison to the previous dataset from an IUPAC task group illustrates a gain in the average energy accuracy by more than one order of magnitude. Based on these levels, a recommended list of transitions between the first five vibrational states is proposed for HD16O in the 0–4650 cm−1 frequency range. Full article
(This article belongs to the Special Issue Molecular Spectroscopy and Molecular Structure in Europe)
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16 pages, 1831 KiB  
Article
Expedient Synthesis of Substituted Thieno[3,2-b]thiophenes and Selenopheno[3,2-b]selenophenes Through Cascade Cyclization of Alkynyl Diol Derivatives
by Yingqi Feng, Xuelin Zhang, Ziqing He, Miaoshan Zhao, Lu Chen, Yibiao Li and Xiai Luo
Molecules 2024, 29(23), 5507; https://doi.org/10.3390/molecules29235507 - 21 Nov 2024
Viewed by 221
Abstract
Thieno[3,2-b]thiophenes are used as key components in optoelectronic materials, porous hydrogen-storage hosts, organic solar cells, and polymer semiconductors. A step-efficient synthetic protocol was proposed herein for obtaining multisubstituted thieno[3,2-b]thiophene and selenopheno[3,2-b]selenophenes in moderate to good yields via [...] Read more.
Thieno[3,2-b]thiophenes are used as key components in optoelectronic materials, porous hydrogen-storage hosts, organic solar cells, and polymer semiconductors. A step-efficient synthetic protocol was proposed herein for obtaining multisubstituted thieno[3,2-b]thiophene and selenopheno[3,2-b]selenophenes in moderate to good yields via the bisulfur/biselenium cyclization of alkynyl diols with I2/Na2S2O3 or selenium. Using this strategy, substitution patterns were obtained for backbone modification in functional materials. Full article
(This article belongs to the Special Issue Recent Advances in Domino Reactions)
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20 pages, 4008 KiB  
Article
Changes in Morphological, Physiological and Phytochemical Traits of Different Dill (Anethum graveolens L.) Cultivars as Affected by Light-Emitting Diodes
by Nafiseh Dehghani, Maryam Haghighi, Mehdi Rahimmalek, Mohammad R. Sabzalian and Antoni Szumny
Molecules 2024, 29(23), 5506; https://doi.org/10.3390/molecules29235506 - 21 Nov 2024
Viewed by 285
Abstract
Dill is a fragrant vegetable containing various beneficial compounds for health. This research aims to evaluate the impact of various spectra of LED light on essential oil composition and morphological and physiological characteristics of three dill cultivars. LED light treatments included greenhouse light [...] Read more.
Dill is a fragrant vegetable containing various beneficial compounds for health. This research aims to evaluate the impact of various spectra of LED light on essential oil composition and morphological and physiological characteristics of three dill cultivars. LED light treatments included greenhouse light as control (C), blue (B), red (R), red + blue (RB), and white (W). RB light enhanced most physiological indicators investigated in this study, including photosynthetic pigments, phenols, flavonoids, and antioxidant capacity. Furthermore, electrolyte leakage in the three cultivars of Khomein, Isfahan, and Varamin decreased when exposed to RB light compared with C light. Under RB light, the essential oil contained more dill ether and α-phellandrene than in other light conditions. In general, light treatment with 75% R light and 25% B light had a noticeable impact on enhancing physiological features compared with other light spectrums. α-phellandrene levels increased in the Isfahan and Varamin cultivars under RB and B light conditions. Finally, the RB light and Khomein cultivars improved physiological features, whereas RB and R light in the Varamin and Isfahan cultivars are recommended for more essential oil compositions in functional food production. Full article
(This article belongs to the Special Issue Plant-Based Food Science: Chemical Composition and Biological Activity)
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14 pages, 809 KiB  
Article
Genistein and Naringenin as Defense Molecules
by Sylwia Goławska, Iwona Łukasik and Paweł Czerniewicz
Molecules 2024, 29(23), 5505; https://doi.org/10.3390/molecules29235505 - 21 Nov 2024
Viewed by 196
Abstract
Genistein and naringenin, plant phenolic compounds, are recognized for their health benefits and role in plant defense against herbivores. However, little research exists on how these compounds affect aphid feeding, particularly that of the black bean aphid (Aphis fabae Scopoli) (Hemiptera: Aphididae), [...] Read more.
Genistein and naringenin, plant phenolic compounds, are recognized for their health benefits and role in plant defense against herbivores. However, little research exists on how these compounds affect aphid feeding, particularly that of the black bean aphid (Aphis fabae Scopoli) (Hemiptera: Aphididae), a major pest. This study aimed to evaluate the effects of genistein and naringenin, applied in vitro at different concentrations, on the feeding behavior of A. fabae. Statistical analysis indicated that both the type and concentration of flavonoids significantly influenced aphid stylet activity, salivation, and ingestion. Higher concentrations of both compounds hindered feeding behavior. A longer initial probe was observed on gels containing the studied flavonoids. Genistein at 0.1% completely inhibited salivation while at 0.01%, it reduced the duration of salivation activities. Both compounds also delayed the start and lengthened the duration of active ingestion, though A. fabae tolerated genistein better than naringenin. Naringenin’s effects on feeding behavior were more pronounced at higher concentrations. These findings suggest that genistein and naringenin could be valuable chemicals to protect plants from aphids in a sustainable and environmentally friendly way. Full article
(This article belongs to the Special Issue Extraction, Characterization, and Potential Applications of Compounds from Natural Sources)
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22 pages, 5400 KiB  
Article
Bioactive Properties of Microencapsulated Anthocyanins from Vaccinium floribundum and Rubus glaucus
by Carlos Barba-Ostria, Rebeca Gonzalez-Pastor, Fabián Castillo-Solís, Saskya E. Carrera-Pacheco, Orestes Lopez, Johana Zúñiga-Miranda, Alexis Debut and Linda P. Guamán
Molecules 2024, 29(23), 5504; https://doi.org/10.3390/molecules29235504 - 21 Nov 2024
Viewed by 216
Abstract
Anthocyanins, widely recognized for their antioxidant properties and potential health benefits, are highly susceptible to degradation due to environmental factors such as light, temperature, and pH leading to reduced bioavailability and efficacy. Microencapsulation, which involves entrapment in a matrix to enhance stability and [...] Read more.
Anthocyanins, widely recognized for their antioxidant properties and potential health benefits, are highly susceptible to degradation due to environmental factors such as light, temperature, and pH leading to reduced bioavailability and efficacy. Microencapsulation, which involves entrapment in a matrix to enhance stability and bioavailability. This study aims to investigate the bioactive properties of microencapsulated anthocyanins derived from Vaccinium floribundum (Andean blueberry) and Rubus glaucus (Andean blackberry). The extracts from V. floribundum and R. glaucus were microencapsulated using maltodextrin as the carrier agent due to its film-forming properties and effectiveness in stabilizing sensitive compounds through a spray-drying process. The microcapsules were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) to assess their chemical and morphological properties. The biological activities of these microencapsulated anthocyanins were evaluated using in vitro assays for their antibacterial, antioxidant, and anti-inflammatory effects. The results indicated enhanced bioactivity of the microencapsulated anthocyanins, suggesting their potential use in developing functional foods and pharmaceuticals. This study provides valuable insights into the effectiveness of microencapsulation in preserving anthocyanins’ functional properties and enhancing their health-promoting effects, highlighting the potential for application in the food and pharmaceutical industries. Full article
(This article belongs to the Special Issue Extraction, Characterization, and Potential Applications of Compounds from Natural Sources)
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