Molecules

18 pages, 2420 KiB

Open AccessReview

Mechanism and Progress of Natural Products in the Treatment of NAFLD-Related Fibrosis

by Jin-Zhong Li, Ning Chen, Nan Ma and Min-Ran Li

Molecules 2023, 28(23), 7936; https://doi.org/10.3390/molecules28237936 - 4 Dec 2023

Cited by 2 | Viewed by 2710

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most prevalent chronic liver disorder worldwide, with liver fibrosis (LF) serving as a pivotal juncture in NAFLD progression. Natural products have demonstrated substantial antifibrotic properties, ushering in novel avenues for NAFLD treatment. This study [...] Read more.

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most prevalent chronic liver disorder worldwide, with liver fibrosis (LF) serving as a pivotal juncture in NAFLD progression. Natural products have demonstrated substantial antifibrotic properties, ushering in novel avenues for NAFLD treatment. This study provides a comprehensive review of the potential of natural products as antifibrotic agents, including flavonoids, polyphenol compounds, and terpenoids, with specific emphasis on the role of Baicalin in NAFLD-associated fibrosis. Mechanistically, these natural products have exhibited the capacity to target a multitude of signaling pathways, including Hedgehog, Wnt/β-catenin, TGF-β1, and NF-κB. Moreover, they can augment the activities of antioxidant enzymes, inhibit pro-fibrotic factors, and diminish fibrosis markers. In conclusion, this review underscores the considerable potential of natural products in addressing NAFLD-related liver fibrosis through multifaceted mechanisms. Nonetheless, it underscores the imperative need for further clinical investigation to authenticate their effectiveness, offering invaluable insights for future therapeutic advancements in this domain. Full article

(This article belongs to the Special Issue Bioactive Compounds from Natural Materials: A New Perspective in Medicinal Chemistry)

► Show Figures

Figure 1

18 pages, 1714 KiB

Open AccessReview

Research Progress on Effects of Ginsenoside Rg2 and Rh1 on Nervous System and Related Mechanisms

by Silu Liu, Weijia Chen, Yan Zhao, Ying Zong, Jianming Li and Zhongmei He

Molecules 2023, 28(23), 7935; https://doi.org/10.3390/molecules28237935 - 4 Dec 2023

Cited by 7 | Viewed by 2637

Abstract

Neurological-related disorders are diseases that affect the body’s neurons or peripheral nerve tissue, such as Parkinson’s disease (PD) and Alzheimer’s disease (AD). The development of neurological disorders can cause serious harm to the quality of life and functioning of the patient. The use [...] Read more.

Neurological-related disorders are diseases that affect the body’s neurons or peripheral nerve tissue, such as Parkinson’s disease (PD) and Alzheimer’s disease (AD). The development of neurological disorders can cause serious harm to the quality of life and functioning of the patient. The use of traditional therapeutic agents such as dopamine-promoting drugs, anticholinergic drugs, cholinesterase inhibitors, and NMDA receptor antagonists is often accompanied by a series of side effects such as drug resistance, cardiac arrhythmia, liver function abnormalities, and blurred vision. Therefore, there is an urgent need to find a therapeutic drug with a high safety profile and few side effects. Herbal medicines are rich in active ingredients that are natural macromolecules. Ginsenoside is the main active ingredient of ginseng, which has a variety of pharmacological effects and is considered to have potential value in the treatment of human diseases. Modern pharmacological studies have shown that ginsenosides Rg2 and Rh1 have strong pharmacological activities in the nervous system, with protective effects on nerve cells, improved resistance to neuronal injury, modulation of neural activity, resistance to cerebral ischemia/reperfusion injury, improvement of brain damage after eclampsia hemorrhage, improvement of memory and cognitive deficits, treatment of AD and vascular dementia, alleviation of anxiety, pain, and inhibition of ionic-like behavior. In this article, we searched the pharmacological research literature of Rg2 and Rh1 in the field of neurological diseases, summarized the latest research progress of the two ginsenosides, and reviewed the pharmacological effects and mechanisms of Rg2 and Rh1, which provided a new way of thinking for the research of the active ingredients in ginseng anti-neurological diseases and the development of new drugs. Full article

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

► Show Figures

Graphical abstract

23 pages, 6413 KiB

Open AccessReview

Progress in the Research on Branched Polymers with Emphasis on the Chinese Petrochemical Industry

by Yi Pan, Jie Bai, Gang Yang and Zhaoxuan Li

Molecules 2023, 28(23), 7934; https://doi.org/10.3390/molecules28237934 - 4 Dec 2023

Cited by 7 | Viewed by 1911

Abstract

Polymer flooding, one of the main methods for improving crude oil recovery using chemical flooding technology in China, is widely used for actual oil displacement. Partially hydrolyzed polyacrylamide (HPAM) is a commonly used linear polymer in polymer flooding, but it exhibits poor temperature [...] Read more.

Polymer flooding, one of the main methods for improving crude oil recovery using chemical flooding technology in China, is widely used for actual oil displacement. Partially hydrolyzed polyacrylamide (HPAM) is a commonly used linear polymer in polymer flooding, but it exhibits poor temperature and salt resistance due to its molecular structure. Therefore, branched polymers have been studied. This article provides a review of the specific synthetic methods and current practical applications in the petrochemical field of dendritic polymers and hyperbranched macromolecules. The advantages and disadvantages of each synthetic method for branched polymers are also elaborated. Finally, the application prospects of branched polymers are discussed. The feasibility of branched polymers in large quantities should be further verified through additional field tests, which should address concerns such as synthesis costs and reaction efficiency. Full article

► Show Figures

Figure 1

15 pages, 1107 KiB

Open AccessReview

Nondestructive Metabolomic Fingerprinting: FTIR, NIR and Raman Spectroscopy in Food Screening

by Nur Cebi, Hatice Bekiroglu and Azime Erarslan

Molecules 2023, 28(23), 7933; https://doi.org/10.3390/molecules28237933 - 4 Dec 2023

Cited by 5 | Viewed by 2931

Abstract

In recent years, there has been renewed interest in the maintenance of food quality and food safety on the basis of metabolomic fingerprinting using vibrational spectroscopy combined with multivariate chemometrics. Nontargeted spectroscopy techniques such as FTIR, NIR and Raman can provide fingerprint information [...] Read more.

In recent years, there has been renewed interest in the maintenance of food quality and food safety on the basis of metabolomic fingerprinting using vibrational spectroscopy combined with multivariate chemometrics. Nontargeted spectroscopy techniques such as FTIR, NIR and Raman can provide fingerprint information for metabolomic constituents in agricultural products, natural products and foods in a high-throughput, cost-effective and rapid way. In the current review, we tried to explain the capabilities of FTIR, NIR and Raman spectroscopy techniques combined with multivariate analysis for metabolic fingerprinting and profiling. Previous contributions highlighted the considerable potential of these analytical techniques for the detection and quantification of key constituents, such as aromatic amino acids, peptides, aromatic acids, carotenoids, alcohols, terpenoids and flavonoids in the food matrices. Additionally, promising results were obtained for the identification and characterization of different microorganism species such as fungus, bacterial strains and yeasts using these techniques combined with supervised and unsupervised pattern recognition techniques. In conclusion, this review summarized the cutting-edge applications of FTIR, NIR and Raman spectroscopy techniques equipped with multivariate statistics for food analysis and foodomics in the context of metabolomic fingerprinting and profiling. Full article

(This article belongs to the Special Issue Application of Metabolomics for Food and Beverages Analysis)

► Show Figures

Figure 1

7 pages, 1532 KiB

Open AccessCommunication

Application of Sonotriboluminescence to Determine Arene Molecules in Hydrocarbons

by Adis A. Tukhbatullin, Nadezhda A. Panova, Dim I. Galimov, Bulat M. Gareev, Alina A. Tukhbatullina, Kristina S. Vasilyuk and Glyus L. Sharipov

Molecules 2023, 28(23), 7932; https://doi.org/10.3390/molecules28237932 - 4 Dec 2023

Viewed by 1121

Abstract

The sonotriboluminescence of suspensions of terbium(III) and europium(III) sulfates in decane without and in the presence of benzene, toluene and p-xylene was studied. The choice of crystals of these lanthanides is due to the fact that they have intense luminescence during mechanical [...] Read more.

The sonotriboluminescence of suspensions of terbium(III) and europium(III) sulfates in decane without and in the presence of benzene, toluene and p-xylene was studied. The choice of crystals of these lanthanides is due to the fact that they have intense luminescence during mechanical action, and also do not dissolve in hydrocarbon solvents. During ultrasonic exposure to suspensions in pure alkanes, bands of Ln³⁺ ions and N₂ in the UV region are recorded in the luminescence spectrum. When aromatic hydrocarbon molecules are added, bands of benzene, toluene and p-xylene molecules, coinciding with their photoluminescence spectra, are recorded in the sonotriboluminescence spectra in the UV region. The high sensitivity of the luminescence of suspensions to arene additives made it possible to obtain the dependence of the characteristic fluorescence of arene molecules in the sonotriboluminescence spectra on their concentration in suspensions. The limits of detection of benzene, toluene and p-xylene in the composition of this suspension were established. The lower limits of detection from the sonotriboluminescence spectra for xylene, toluene and benzene are 0.1, 3 and 50 ppmv, respectively. Fluorescence bands of these molecules were also recorded in the sonotriboluminescence spectra of suspensions in commercial dodecane and heptane with additives of commercial gasoline (up to 1%). The results obtained can be used for luminescent detection of aromatic compounds in saturated hydrocarbons. Full article

(This article belongs to the Section Ultrasound Chemistry)

► Show Figures

Graphical abstract

12 pages, 3900 KiB

Open AccessArticle

Indole Diterpene Derivatives from the Aspergillus flavus GZWMJZ-288, an Endophytic Fungus from Garcinia multiflora

by Dongyang Wang, Xiaohong Zhuang, Ying Yin, Dan Wu, Wenwen He, Weiming Zhu, Yanchao Xu, Mingxing Zuo and Liping Wang

Molecules 2023, 28(23), 7931; https://doi.org/10.3390/molecules28237931 - 4 Dec 2023

Cited by 1 | Viewed by 1455

Abstract

A new indole diterpene, 26-dihydroxyaflavininyl acetate (1), along with five known analogs (2–6) were isolated from the liquid fermentation of Aspergillus flavus GZWMJZ-288, an endophyte from Garcinia multiflora. The structures of these compounds were identified through [...] Read more.

A new indole diterpene, 26-dihydroxyaflavininyl acetate (1), along with five known analogs (2–6) were isolated from the liquid fermentation of Aspergillus flavus GZWMJZ-288, an endophyte from Garcinia multiflora. The structures of these compounds were identified through NMR, MS, chemical reaction, and X-ray diffraction experiments. Enzyme inhibition activity screening found that compounds 1, 4, and 6 have a good binding affinity with NPC1L1, among which compound 6 exhibited a stronger binding ability than ezetimibe at a concentration of 10 µM. Moreover, compound 5 showed inhibitory activity against α-glucosidase with an IC₅₀ value of 29.22 ± 0.83 µM, which is 13 times stronger than that of acarbose. The results suggest that these aflavinine analogs may serve as lead compounds for the development of drugs targeting NPC1L1 and α-glucosidase. The binding modes of the bioactive compounds with NPC1L1 and α-glucosidase were also performed through in silico docking studies. Full article

(This article belongs to the Section Natural Products Chemistry)

► Show Figures

Graphical abstract

11 pages, 1306 KiB

Open AccessArticle

Antifungal and Phytotoxic Activities of Isolated Compounds from Helietta parvifolia Stems

by Victor Pena Ribeiro, Joanna Bajsa-Hirschel, Prabin Tamang, Kumudini Meepagala and Stephen O. Duke

Molecules 2023, 28(23), 7930; https://doi.org/10.3390/molecules28237930 - 4 Dec 2023

Cited by 2 | Viewed by 1352

Abstract

The identification of natural and environmentally friendly pesticides is a key area of interest for the agrochemical industry, with many potentially active compounds being sourced from numerous plant species. In this study, we report the bioassay-guided isolation and identification of phytotoxic and antifungal [...] Read more.

The identification of natural and environmentally friendly pesticides is a key area of interest for the agrochemical industry, with many potentially active compounds being sourced from numerous plant species. In this study, we report the bioassay-guided isolation and identification of phytotoxic and antifungal compounds from the ethyl acetate extract of Helietta parvifolia stems. We identified eight compounds, consisting of two coumarins and six alkaloids. Among these, a new alkaloid, 2-hydroxy-3,6,7-trimethoxyquinoline-4-carbaldehyde (6), was elucidated, along with seven known compounds. The phytotoxicity of purified compounds was evaluated, and chalepin (4) was active against Agrostis stolonifera at 1 mM with 50% inhibition of seed germination and it reduced Lemna pausicotata (duckweed) growth by 50% (IC₅₀) at 168 μM. Additionally, we evaluated the antifungal activity against the fungal plant pathogen Colletotrichum fragariae using a thin-layer chromatography bioautography assay, which revealed that three isolated furoquinoline alkaloids (flindersiamine (3), kokusagenine (7), and maculine (8)) among the isolated compounds had the strongest inhibitory effects on the growth of C. fragariae at all tested concentrations. Our results indicate that these active natural compounds, i.e., (3), (4), (7), and (8), could be scaffolds for the production of more active pesticides with better physicochemical properties. Full article

(This article belongs to the Special Issue Analysis and Identification of Natural Product Extracts for Use in Medicine, Public Health and Agriculture)

► Show Figures

Figure 1

19 pages, 1066 KiB

Open AccessReview

Effects of Natural Products on Enzymes Involved in Ferroptosis: Regulation and Implications

by Hua-Li Zuo, Hsi-Yuan Huang, Yang-Chi-Dung Lin, Kun-Meng Liu, Ting-Syuan Lin, Yi-Bing Wang and Hsien-Da Huang

Molecules 2023, 28(23), 7929; https://doi.org/10.3390/molecules28237929 - 4 Dec 2023

Cited by 5 | Viewed by 2417

Abstract

Ferroptosis is a form of regulated cell death that is characterized by the accumulation of iron-dependent lipid peroxides. The regulation of ferroptosis involves both non-enzymatic reactions and enzymatic mechanisms. Natural products have demonstrated potential effects on various enzymes, including GPX4, HO-1, NQO1, NOX4, [...] Read more.

Ferroptosis is a form of regulated cell death that is characterized by the accumulation of iron-dependent lipid peroxides. The regulation of ferroptosis involves both non-enzymatic reactions and enzymatic mechanisms. Natural products have demonstrated potential effects on various enzymes, including GPX4, HO-1, NQO1, NOX4, GCLC, and GCLM, which are mainly involved in glutathione metabolic pathway or oxidative stress regulation, and ACSL3 and ACSL4, which mainly participate in lipid metabolism, thereby influencing the regulation of ferroptosis. In this review, we have provided a comprehensive overview of the existing literature pertaining to the effects of natural products on enzymes involved in ferroptosis and discussed their potential implications for the prevention and treatment of ferroptosis-related diseases. We also highlight the potential challenge that the majority of research has concentrated on investigating the impact of natural products on the expression of enzymes involving ferroptosis while limited attention is given to the regulation of enzyme activity. This observation underscores the considerable potential and scope for exploring the influence of natural products on enzyme activity. Full article

(This article belongs to the Special Issue Discovery of Enzyme Inhibitors from Natural Products II)

► Show Figures

Figure 1

12 pages, 8522 KiB

Open AccessArticle

Effect of Surface Pt Doping on the Reactivity of Au(111) Surfaces towards Methanol Dehydrogenation: A First-Principles Density Functional Theory Investigation

by Merve Demirtas, Hande Ustunel and Daniele Toffoli

Molecules 2023, 28(23), 7928; https://doi.org/10.3390/molecules28237928 - 4 Dec 2023

Viewed by 1421

Abstract

The surprisingly high catalytic activity of gold has been known to the heterogeneous catalysis community since the mid-1980s. Significant efforts have been directed towards improving the reactivity of these surfaces towards important industrial reactions. One such strategy is the introduction of small amounts [...] Read more.

The surprisingly high catalytic activity of gold has been known to the heterogeneous catalysis community since the mid-1980s. Significant efforts have been directed towards improving the reactivity of these surfaces towards important industrial reactions. One such strategy is the introduction of small amounts of other metals to create Au-based surface alloys. In this work, we investigated the synergistic effect of the Pt doping of a Au(111) surface on decreasing the activation barrier of the methanol dehydrogenation elementary step within first-principles density functional theory. To this end, we constructed several models of Pt-doped Au(111) surfaces, including a full Pt overlayer and monolayer. The effect of Pt surface doping was then investigated via the computation of the adsorption energies of the various chemical species involved in the catalytic step and the estimation of the activation barriers of methanol dehydrogenation. Both the electronic and strain effects induced by Pt surface doping substantially lowered the activation energy barrier of this important elementary reaction step. Moreover, in the presence of preadsorbed atomic oxygen, Pt surface doping could be used to reduce the activation energy for methanol dehydrogenation to as low as 0.1 eV. Full article

(This article belongs to the Special Issue Advances in Theoretical Understanding of Nanomaterial Systems through Computer Simulations)

► Show Figures

Figure 1

20 pages, 3979 KiB

Open AccessArticle

Oxidation Treatments Using Hydrogen Peroxide to Convert Paper-Grade Eucalyptus Kraft Pulp into Dissolving-Grade Pulp

by Andrea Vera-Loor, Panagiota Rigou, Gérard Mortha and Nathalie Marlin

Molecules 2023, 28(23), 7927; https://doi.org/10.3390/molecules28237927 - 4 Dec 2023

Cited by 1 | Viewed by 1964

Abstract

Converting paper-grade bleached Kraft pulp into dissolving pulp using eco-friendly chemicals on-site at the mill is a challenge for the pulp industry. In this study, two oxidation systems are evaluated: the first one is based on the use of hydrogen peroxide at various [...] Read more.

Converting paper-grade bleached Kraft pulp into dissolving pulp using eco-friendly chemicals on-site at the mill is a challenge for the pulp industry. In this study, two oxidation systems are evaluated: the first one is based on the use of hydrogen peroxide at various levels of alkalinity; the second one investigates the use of sodium periodate followed by hydrogen peroxide to convert aldehydes into carboxyls and enhance their hemicelluloses removal. Our results have shown that when using only peroxide, the removal of hemicelluloses was not sufficient to improve the pulp’s dissolving ability. Conversely, the periodate–peroxide system proved to be more efficient. Results regarding the pulp purity, solubility, degradation (pulp viscosity and cellulose molecular mass distribution), brightness, and its potential applications were discussed. Full article

(This article belongs to the Section Analytical Chemistry)

► Show Figures

Figure 1

14 pages, 4147 KiB

Open AccessArticle

Pharmacological Evidence That Dictyostelium Differentiation-Inducing Factor 1 Promotes Glucose Uptake Partly via an Increase in Intracellular cAMP Content in Mouse 3T3-L1 Cells

by Yuzuru Kubohara, Yuko Fukunaga, Haruhisa Kikuchi and Hidekazu Kuwayama

Molecules 2023, 28(23), 7926; https://doi.org/10.3390/molecules28237926 - 4 Dec 2023

Cited by 2 | Viewed by 1540

Abstract

Differentiation-inducing factor 1 (DIF-1) isolated from the cellular slime mold Dictyostelium discoideum can inhibit mammalian calmodulin-dependent cAMP/cGMP phosphodiesterase (PDE1) in vitro. DIF-1 also promotes glucose uptake, at least in part, via a mitochondria- and AMPK-dependent pathway in mouse 3T3-L1 fibroblast cells, but the [...] Read more.

Differentiation-inducing factor 1 (DIF-1) isolated from the cellular slime mold Dictyostelium discoideum can inhibit mammalian calmodulin-dependent cAMP/cGMP phosphodiesterase (PDE1) in vitro. DIF-1 also promotes glucose uptake, at least in part, via a mitochondria- and AMPK-dependent pathway in mouse 3T3-L1 fibroblast cells, but the mechanism underlying this effect has not been fully elucidated. In this study, we investigated the effects of DIF-1 on intracellular cAMP and cGMP levels, as well as the effects that DIF-1 and several compounds that increase cAMP and cGMP levels have on glucose uptake in confluent 3T3-L1 cells. DIF-1 at 20 μM (a concentration that promotes glucose uptake) increased the level of intracellular cAMP by about 20% but did not affect the level of intracellular cGMP. Neither the PDE1 inhibitor 8-methoxymethyl-3-isobutyl-1-methylxanthine at 10–200 μM nor the broad-range PDE inhibitor 3-isobutyl-1-methylxanthine at 40–400 μM had any marked effects on glucose uptake. The membrane-permeable cAMP analog 8-bromo-cAMP at 200–1000 μM significantly promoted glucose uptake (by 20–25%), whereas the membrane-permeable cGMP analog 8-bromo-cGMP at 3–100 μM did not affect glucose uptake. The adenylate cyclase activator forskolin at 1–10 μM promoted glucose uptake by 20–30%. Thus, DIF-1 may promote glucose uptake by 3T3-L1 cells, at least in part, via an increase in intracellular cAMP level. Full article

► Show Figures

Figure 1

10 pages, 912 KiB

Open AccessArticle

Application of Accelerated Predictive Stability Studies in Extemporaneously Compounded Formulations of Chlorhexidine to Assess the Shelf Life

by Olga González-González, M. Paloma Ballesteros, Juan J. Torrado and Dolores R. Serrano

Molecules 2023, 28(23), 7925; https://doi.org/10.3390/molecules28237925 - 4 Dec 2023

Cited by 2 | Viewed by 2636

Abstract

Industrially fabricated medicines have a well-defined shelf life supported by rigorous studies before their approval for commercialization. However, the shelf life of extemporaneous compounding topical formulations prepared at hospitals tends to be shorter, especially when no data are available to prove a longer [...] Read more.

Industrially fabricated medicines have a well-defined shelf life supported by rigorous studies before their approval for commercialization. However, the shelf life of extemporaneous compounding topical formulations prepared at hospitals tends to be shorter, especially when no data are available to prove a longer stability period. Also, the storage conditions are unknown in many circumstances. Accelerated Predictive Stability (APS) studies have been shown to be a useful tool to predict in a faster and more accurate manner the chemical stability of extemporaneously compounded formulations requiring a minimum amount of formulation, thereby reducing the chemical drug waste per study. Shelf life will be allocated based on scientific data without compromising drug efficacy or safety. In this work, the APS approach was applied to the commercially available Cristalmina^® (CR) and an extemporaneously compounded formulation of chlorhexidine (DCHX). A different degradation kinetic was found between DCHX and CR (Avrami vs. zero-order kinetics, respectively). This can explain the different shelf life described by the International Council for Harmonisation of Technical Requirements Registration Pharmaceuticals Human Use (ICH) conditions between both formulations. A predicted stability for the DCHX solution was obtained from the extrapolation of the degradation rate in long-term conditions from the Arrhenius equation. The estimated degradation from the Arrhenius equation for DCHX at 5 °C, 25 °C, and 30 °C at 365 days was 3.1%, 17.4%, and 25.9%, respectively. The predicted shelf life, in which the DCHX content was above 90%, was 26.67 months under refrigerated conditions and 5.75 and 2.24 months at 25 and 30 °C, respectively. Currently, the Spanish National Formulary recommends a shelf life of no longer than 3 months at room temperature for DCHX solution. Based on the predicted APS and confirmed by experimental long-term studies, we have demonstrated that the shelf life of DCHX extemporaneously compounded formulations could be prolonged by up to 6 months. Full article

(This article belongs to the Special Issue Advanced Analytical Tools for Characterization and Quality Control of Food, Drugs, and Natural Active Ingredients, 2nd Edition)

► Show Figures

Graphical abstract

17 pages, 7433 KiB

Open AccessArticle

Enhancing c-Si Solar Cell Efficiency in the UV Region: Photophysical Insights into the Use of Eu³⁺ Complexes for Down-Shifting Layer Applications

by Fabian Vargas, Ronald Nelson, Dario Espinoza, Ivan Brito, Laura Sánchez-Muñoz, Pere Alemany, Sergio Ortiz, Pablo Ferrada, Alifhers Mestra and Jaime Llanos

Molecules 2023, 28(23), 7924; https://doi.org/10.3390/molecules28237924 - 4 Dec 2023

Viewed by 1738

Abstract

[Eu(³DPIQC)₃] (where DPIQC = 3-(diphenyl phosphoryl)-1-isoquinolinecarboxylate), a luminescent europium complex with antenna ligands, has been carefully embedded within a polyvinyl butyral (PVB) matrix and the resulting material was used to prepare films used as luminescent down-shifting layers (LDSLs) for [...] Read more.

[Eu(³DPIQC)₃] (where DPIQC = 3-(diphenyl phosphoryl)-1-isoquinolinecarboxylate), a luminescent europium complex with antenna ligands, has been carefully embedded within a polyvinyl butyral (PVB) matrix and the resulting material was used to prepare films used as luminescent down-shifting layers (LDSLs) for crystalline Si-based solar cells. The films were characterized using photoluminescence spectroscopy, atomic force spectroscopy (AFM), UV-Vis spectroscopy, and fluorescence microscopy. The AFM analysis shows films with low surface roughness, while fluorescence microscopy revealed that the Eu complex embedded in PVB assumed a spheroidal configuration, a morphology especially beneficial for optical applications. The so-obtained LDSLs were utilized as energy converters in c-Si solar cells to enhance the utilization of high-energy photons, thereby improving their overall efficiency. The determination of photovoltaic parameters carried out before and after the deposition of the LDSLs on the c-Si cells confirms a positive effect on the efficiency of the cell. The J_sc increases from 121.6 mA/cm² to 124.9 mA/cm², and the open circuit voltage (V_oc) is found to be unrelated to the complex concentration in the films. The fill factor (FF) remains constant with the Eu concentration. The EQE curves indicate an enhancement in the performance of the photovoltaic cells within the UV region of the spectrum for all coated devices. Electrochemical impedance spectroscopy (EIS) was also carried out in order to analyze the effect of the Eu complex in the charge transfer process of the devices. Full article

(This article belongs to the Special Issue Advanced Optoelectronic Materials with Outstanding Chemical and Physical Properties: Design, Characterization and Applications)

► Show Figures

Graphical abstract

17 pages, 5989 KiB

Open AccessArticle

Effects of Different Flotation Agents on the Nucleation and Growth of Potassium Chloride

by Guangle Wang, Xiao Bian, Zeren Shang, Weibing Dong, Yi Zhang and Songgu Wu

Molecules 2023, 28(23), 7923; https://doi.org/10.3390/molecules28237923 - 4 Dec 2023

Cited by 1 | Viewed by 1479

Abstract

The flotation agent is an important collector in the production of potassium chloride and is brought into the crystallization stage with the reflux of the mother liquor. Octadecylamine Hydrochloride (ODA), 1-Dodecylamine Hydrochloride (DAH) and Sodium 1-dodecanesulfonate (SDS) were selected to study their effect [...] Read more.

The flotation agent is an important collector in the production of potassium chloride and is brought into the crystallization stage with the reflux of the mother liquor. Octadecylamine Hydrochloride (ODA), 1-Dodecylamine Hydrochloride (DAH) and Sodium 1-dodecanesulfonate (SDS) were selected to study their effect on the nucleation of potassium chloride. Focused Beam Reflectance Measurement was used to collect the nucleation-induced periods of KCl in the presence of flotation agents at different supersaturations. Then, empirical equations, classical nucleation theory and growth mechanism equations were employed for data analysis. It was found that the presence of flotation agents increased the nucleation sequence m, and m(ODA) > m(SDS) > m(DAH) > m(H₂O). In addition, the interfacial energy data obtained using classical nucleation theory suggest that the flotation agents used in our paper promoted the homogeneous nucleation of KCl (reduced from 5.3934 mJ·m⁻² to 5.1434 mJ·m⁻²) and inhibited the heterogeneous nucleation of KCl (increased from 2.8054 mJ·m⁻² to 3.6004 mJ·m⁻²). This investigation also revealed that the growth of potassium chloride was consistent with the 2D nucleation-mediated growth mechanism, and the addition of flotation agent did not change the growth mechanism of potassium chloride. Finally, the particle size distribution results were exactly consistent with the order of nucleation order m. The study of nucleation kinetics and growth mechanisms of different flotation agents on potassium chloride can provide guidance for optimizing the production process of potassium chloride and developing new flotation agents. Full article

(This article belongs to the Special Issue Thermodynamics, Structure, and Intermolecular Interactions in Solutions—Second Edition)

► Show Figures

Graphical abstract

15 pages, 2935 KiB

Open AccessReview

A Review of Synthesis and Applications of Al₂O₃ for Organic Dye Degradation/Adsorption

by Sundarakannan Rajendran, Geetha Palani, Vigneshwaran Shanmugam, Herri Trilaksanna, Karthik Kannan, Marek Nykiel, Kinga Korniejenko and Uthayakumar Marimuthu

Molecules 2023, 28(23), 7922; https://doi.org/10.3390/molecules28237922 - 4 Dec 2023

Cited by 4 | Viewed by 2430

Abstract

This comprehensive review investigates the potential of aluminum oxide (Al₂O₃) as a highly effective adsorbent for organic dye degradation. Al₂O₃ emerges as a promising solution to address environmental challenges associated with dye discharge due to its [...] Read more.

This comprehensive review investigates the potential of aluminum oxide (Al₂O₃) as a highly effective adsorbent for organic dye degradation. Al₂O₃ emerges as a promising solution to address environmental challenges associated with dye discharge due to its solid ceramic composition, robust mechanical properties, expansive surface area, and exceptional resistance to environmental degradation. The paper meticulously examines recent advancements in Al₂O₃-based materials, emphasizing their efficacy in both organic dye degradation and adsorption. Offering a nuanced understanding of Al₂O₃’s pivotal role in environmental remediation, this review provides a valuable synthesis of the latest research developments in the field of dye degradation. It serves as an insightful resource, emphasizing the significant potential of aluminum oxide in mitigating the pressing environmental concerns linked to organic dye discharge. The application of Al₂O₃-based catalysts in the photocatalytic treatment of multi-component organic dyes necessitates further exploration, particularly in addressing real-world wastewater complexities. Full article

(This article belongs to the Special Issue Advanced Materials for Energy Conversion and Water Sustainability)

► Show Figures

Figure 1

12 pages, 3984 KiB

Open AccessArticle

The Synergistic Effect of Biosynthesized Silver Nanoparticles and Phytocompound as a Novel Approach to the Elimination of Pathogens

by Natalia Wrońska, Sara Płaczkowska, Katarzyna Niedziałkowska and Katarzyna Lisowska

Molecules 2023, 28(23), 7921; https://doi.org/10.3390/molecules28237921 - 4 Dec 2023

Cited by 2 | Viewed by 1573

Abstract

Due to the wide applications of silver nanoparticles (AgNPs), research on their ecological synthesis has been extensive in recent years. In our study, biogenic silver nanoparticles were synthesized extracellularly using the white rot fungus Trametes versicolor via two cultivation methods: static and shaking. The [...] Read more.

Due to the wide applications of silver nanoparticles (AgNPs), research on their ecological synthesis has been extensive in recent years. In our study, biogenic silver nanoparticles were synthesized extracellularly using the white rot fungus Trametes versicolor via two cultivation methods: static and shaking. The cell filtrate of the fungus was used as a reducing agent in the process of nanoparticle synthesis. Characterization of the obtained nanoparticles was carried out using UV–VIS spectroscopy and scanning electron microscopy. The biosynthesized nanoparticles have antimicrobial potential against pathogenic bacteria, particularly in Gram-negative strains. The bactericidal effect was obtained for E. coli at a concentration of 7 µg/mL. The use of higher concentrations of compounds was necessary for Gram-positive bacteria. Taking into account the problem of the risk of cytotoxicity of AgNPs, combined therapy using a phytochemical was used for the first time, which was aimed at reducing the doses of nanoparticles. The most representative synergistic effect was observed in the treatment of 5 µg/mL silver nanoparticles in combination with 15 µg/mL ursolic acid against E. coli and P. aeruginosa with a bactericidal effect. Moreover, the coadministration of nanoparticles considerably reduced the growth of both Staphylococcus strains, with a bactericidal effect against S. aureus. The viability test confirmed the strong synergistic effect of both tested compounds. Silver nanoparticles synthesized using the T. versicolor showed excellent antibacterial potential, which opens perspectives for future investigations concerning the use of the nanoparticles as antimicrobials in the areas of health. Full article

► Show Figures

Figure 1

13 pages, 9296 KiB

Open AccessArticle

Mesoporous-Layered Double Oxide/MCM-41 Composite with Enhanced Catalytic Performance for Cyclopentanone Aldol Condensation

by Jinfan Yang, Ning Shang, Jiachen Wang and Huimin Liu

Molecules 2023, 28(23), 7920; https://doi.org/10.3390/molecules28237920 - 3 Dec 2023

Viewed by 1492

Abstract

Layered double oxides are widely employed in catalyzing the aldol condensation for producing biofuels, but its selectivity and stability need to be further improved. Herein, a novel MCM-41-supported Mg–Al-layered double oxide (LDO/MCM-41) was prepared via the in situ integration of a sol–gel process [...] Read more.

Layered double oxides are widely employed in catalyzing the aldol condensation for producing biofuels, but its selectivity and stability need to be further improved. Herein, a novel MCM-41-supported Mg–Al-layered double oxide (LDO/MCM-41) was prepared via the in situ integration of a sol–gel process and coprecipitation, followed by calcination. This composite was first employed to catalyze the self-condensation of cyclopentanone for producing high-density cycloalkane precursors. LDO/MCM-41 possessed large specific surface area, uniform pore size distribution, abundant medium basic sites and Bronsted acid sites. Compared with the bulk LDO, LDO/MCM-41 exhibited a higher selectivity for C10 and C15 oxygenates at 150 °C (93.4% vs. 84.6%). The selectivity for C15 was especially enhanced on LDO/MCM-41, which was three times greater than that on LDO. The stability test showed that naked LDO with stronger basic strength had a rapid initial activity, while it suffered an obvious deactivation due to its poor carbon balance. LDO/MCM-41 with lower basic strength had an enhanced stability even with a lower initial activity. Under the optimum conditions (50% LDO loading, 170 °C, 7 h), the cyclopentanone conversion on LDO/MCM-41 reached 77.8%, with a 60% yield of C10 and 15.2% yield of C15. Full article

(This article belongs to the Special Issue Porous Materials as Catalysts and Sorbents)

► Show Figures

Graphical abstract

15 pages, 3244 KiB

Open AccessArticle

Helium Cold Atmospheric Plasma Causes Morphological and Biochemical Alterations in Candida albicans Cells

by Sabrina de Moura Rovetta-Nogueira, Aline Chiodi Borges, Maurício de Oliveira Filho, Thalita Mayumi Castaldelli Nishime, Luis Rogerio de Oliveira Hein, Konstantin Georgiev Kostov and Cristiane Yumi Koga-Ito

Molecules 2023, 28(23), 7919; https://doi.org/10.3390/molecules28237919 - 3 Dec 2023

Cited by 2 | Viewed by 1441

Abstract

(1) Background: Previous studies reported the promising inhibitory effect of cold atmospheric plasma (CAP) on Candida albicans. However, the exact mechanisms of CAP’s action on the fungal cell are still poorly understood. This study aims to elucidate the CAP effect on C. [...] Read more.

(1) Background: Previous studies reported the promising inhibitory effect of cold atmospheric plasma (CAP) on Candida albicans. However, the exact mechanisms of CAP’s action on the fungal cell are still poorly understood. This study aims to elucidate the CAP effect on C. albicans cell wall, by evaluating the alterations on its structure and biochemical composition; (2) Methods: C. albicans cells treated with Helium-CAP were analyzed by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) in order to detect morphological, topographic and biochemical changes in the fungal cell wall. Cells treated with caspofungin were also analyzed for comparative purposes; (3) Results: Expressive morphological and topographic changes, such as increased roughness and shape modification, were observed in the cells after CAP exposure. The alterations detected were similar to those observed after the treatment with caspofungin. The main biochemical changes occurred in polysaccharides content, and an overall decrease in glucans and an increase in chitin synthesis were detected; (4) Conclusions: Helium-CAP caused morphological and topographic alterations in C. albicans cells and affected the cell wall polysaccharide content. Full article

(This article belongs to the Special Issue Plasma Technology and Biomedical Applications)

► Show Figures

Figure 1

10 pages, 4573 KiB

Open AccessArticle

Facile Synthesis of Nd₂Fe₁₄B Hard Magnetic Particles with Microwave-Assisted Hydrothermal Method

by Ling Wang and Xiaofen Xu

Molecules 2023, 28(23), 7918; https://doi.org/10.3390/molecules28237918 - 3 Dec 2023

Cited by 2 | Viewed by 1236

Abstract

The synthesis of Nd-Fe-B magnetic powders via chemical techniques presents significant promise, but poses challenges due to their inherent chemical instability. In this investigation, Nd-Fe-B hard magnetic particles were synthesized utilizing an eco-friendly and simple microwave-assisted hydrothermal synthetic method. The technique involves the [...] Read more.

The synthesis of Nd-Fe-B magnetic powders via chemical techniques presents significant promise, but poses challenges due to their inherent chemical instability. In this investigation, Nd-Fe-B hard magnetic particles were synthesized utilizing an eco-friendly and simple microwave-assisted hydrothermal synthetic method. The technique involves the synthesis of the Nd-Fe-B oxide precursor using the microwave-assisted hydrothermal method, followed by reduction–diffusion using CaH₂. The microwave-assisted hydrothermal technique presents a viable approach for preparing Nd-Fe-B precursor particles, offering advantages such as time and energy efficiency and environmental sustainability. The synthesized Nd-Fe-B particles demonstrated a coercivity of up to 2.3 kOe. These magnetic particles hold significant potential for use in high-performance permanent magnets, and can effectively contribute to developing high-energy density exchange-coupled nanocomposite magnets. This study also offers valuable insights into the design and synthesis of additional magnetic materials based on rare earth elements. Full article

(This article belongs to the Special Issue Analysis and Characterization of Materials in Chemistry)

► Show Figures

Figure 1

10 pages, 1252 KiB

Open AccessArticle

Comparative Analysis of Spray-Dried Porcine Plasma and Hydrolyzed Porcine Protein as Animal-Blood-Derived Protein Ingredients for Pet Nutrition

by Katarzyna Kazimierska and Wioletta Biel

Molecules 2023, 28(23), 7917; https://doi.org/10.3390/molecules28237917 - 3 Dec 2023

Cited by 2 | Viewed by 2448

Abstract

Spray-dried porcine plasma (SDPP) and hydrolyzed porcine protein (HPP) are promising animal protein ingredients sourced from healthy animal blood that are rich in biomolecules, including immunoglobulins, and can be an appropriate and valuable animal protein ingredient to supply the growing need for ingredients [...] Read more.

Spray-dried porcine plasma (SDPP) and hydrolyzed porcine protein (HPP) are promising animal protein ingredients sourced from healthy animal blood that are rich in biomolecules, including immunoglobulins, and can be an appropriate and valuable animal protein ingredient to supply the growing need for ingredients that meet the natural needs of carnivorous pets. The aim of this preliminary study was to analyze the chemical composition and mineral profile of a novel HPP compared with results for SDPP. The basic composition analysis followed AOAC guidelines, and the elemental analysis utilized atomic absorption spectrometry. Statistical comparisons employed an independent Student’s t-test (p < 0.05). Both SDPP and HPP are low in moisture (<4.3%) and rich in protein, with SDPP significantly exceeding HPP (75.4% vs. 71.4%). They boast mineral richness indicated by crude ash content (12.7% and 12.5%), featuring Na, K, P, and the trace elements Mo, Fe, and Zn. Notably, SDPP contains elevated molybdenum levels (51.39 mg/100 g vs. 10.93 mg/100 g in HPP), an essential element for diverse animal functions. Quantifying these elements in raw materials aids in achieving optimal nutrient levels in the final product. The study underscores SDPP as an excellent protein source, confirming that its nutritional value is similar to or better than other protein components in pet food. Full article

(This article belongs to the Special Issue Biomolecules of Natural Origin: Fundamentals and Applications)

► Show Figures

Figure 1

26 pages, 4639 KiB

Open AccessReview

Recent Advances on Electrochemical Sensors for Detection of Contaminants of Emerging Concern (CECs)

by Chinchu Gibi, Cheng-Hua Liu, Sambandam Anandan and Jerry J. Wu

Molecules 2023, 28(23), 7916; https://doi.org/10.3390/molecules28237916 - 3 Dec 2023

Cited by 2 | Viewed by 2555

Abstract

Contaminants of Emerging Concern (CECs), a new category of contaminants currently in the limelight, are a major issue of global concern. The pervasive nature of CECs and their harmful effects, such as cancer, reproductive disorders, neurotoxicity, etc., make the situation alarming. The perilous [...] Read more.

Contaminants of Emerging Concern (CECs), a new category of contaminants currently in the limelight, are a major issue of global concern. The pervasive nature of CECs and their harmful effects, such as cancer, reproductive disorders, neurotoxicity, etc., make the situation alarming. The perilous nature of CECs lies in the fact that even very small concentrations of CECs can cause great impacts on living beings. They also have a nature of bioaccumulation. Thus, there is a great need to have efficient sensors for the detection of CECs to ensure a safe living environment. Electrochemical sensors are an efficient platform for CEC detection as they are highly selective, sensitive, stable, reproducible, and prompt, and can detect very low concentrations of the analyte. Major classes of CECs are pharmaceuticals, illicit drugs, personal care products, endocrine disruptors, newly registered pesticides, and disinfection by-products. This review focusses on CECs, including their sources and pathways, health effects caused by them, and electrochemical sensors as reported in the literature under each category for the detection of major CECs. Full article

(This article belongs to the Section Materials Chemistry)

► Show Figures

Graphical abstract

11 pages, 1129 KiB

Open AccessArticle

A Facile and General Oxidative Hydroxylation of Organoboron Compounds: Citric Acid as an Efficient Catalyst in Water to Access Phenolic and Alcoholic Motifs

by Jia-Hui Zhou, Xia Chen, Dan Yang, Chun-Yan Liu and Xiao-Yu Zhou

Molecules 2023, 28(23), 7915; https://doi.org/10.3390/molecules28237915 - 3 Dec 2023

Cited by 2 | Viewed by 1391

Abstract

An efficient and convenient method for the synthesis of phenols and aliphatic alcohols is described in this paper. The oxidative hydroxylation reaction of various organoboron compounds proceeded smoothly by employing H₂O₂ as the oxidant and citric acid as the catalyst [...] Read more.

An efficient and convenient method for the synthesis of phenols and aliphatic alcohols is described in this paper. The oxidative hydroxylation reaction of various organoboron compounds proceeded smoothly by employing H₂O₂ as the oxidant and citric acid as the catalyst in water at room temperature to produce phenols and aliphatic alcohols in satisfactory to excellent yields (up to 99% yield). Various synthetically useful functional groups, such as halogen atom, cyano, and nitro groups, remain intact during the oxidative hydroxylation. The developed catalytic system also could accommodate phenylboronic pinacol ester and potassium phenyltrifluoroborate to give the target product good yields. Full article

(This article belongs to the Topic Green and Sustainable Chemistry)

► Show Figures

Graphical abstract

12 pages, 13023 KiB

Open AccessArticle

An AIE Metal Iridium Complex: Photophysical Properties and Singlet Oxygen Generation Capacity

by Weijin Zhu, Shengnan Liu, Ziwei Wang, Chunguang Shi, Qiaohua Zhang, Zihan Wu, Guangzhe Li and Dongxia Zhu

Molecules 2023, 28(23), 7914; https://doi.org/10.3390/molecules28237914 - 3 Dec 2023

Cited by 1 | Viewed by 1702

Abstract

Photodynamic therapy (PDT) has garnered significant attention in the fields of cancer treatment and drug-resistant bacteria eradication due to its non-invasive nature and spatiotemporal controllability. Iridium complexes have captivated researchers owing to their tunable structure, exceptional optical properties, and substantial Stokes displacement. However, [...] Read more.

Photodynamic therapy (PDT) has garnered significant attention in the fields of cancer treatment and drug-resistant bacteria eradication due to its non-invasive nature and spatiotemporal controllability. Iridium complexes have captivated researchers owing to their tunable structure, exceptional optical properties, and substantial Stokes displacement. However, most of these complexes suffer from aggregation-induced quenching, leading to diminished luminous efficiency. In contrast to conventional photosensitizers, photosensitizers exhibiting aggregation-induced luminescence (AIE) properties retain the ability to generate a large number of reactive oxygen species when aggregated. To overcome these limitations, we designed and synthesized a novel iridium complex named Ir-TPA in this study. It incorporates quinoline triphenylamine cyclomethylated ligands that confer AIE characteristics for Ir-TPA. We systematically investigated the photophysical properties, AIE behavior, spectral features, and reactive oxygen generation capacity of Ir-TPA. The results demonstrate that Ir-TPA exhibits excellent optical properties with pronounced AIE phenomenon and robust capability for producing singlet oxygen species. This work not only introduces a new class of metal iridium complex photosensitizer with AIE attributes but also holds promise for achieving remarkable photodynamic therapeutic effects in future cellular experiments and biological studies. Full article

(This article belongs to the Special Issue Synthesis and Applications of Transition Metal Complexes)

► Show Figures

Figure 1

16 pages, 1418 KiB

Open AccessArticle

A Green Bioactive By-Product Almond Skin Functional Extract for Developing Nutraceutical Formulations with Potential Antimetabolic Activity

by Patrizia Picerno, Lucia Crascì, Patrizia Iannece, Tiziana Esposito, Silvia Franceschelli, Michela Pecoraro, Virgilio Giannone, Anna Maria Panico, Rita Patrizia Aquino and Maria Rosaria Lauro

Molecules 2023, 28(23), 7913; https://doi.org/10.3390/molecules28237913 - 3 Dec 2023

Cited by 3 | Viewed by 2051

Abstract

(1) Background: almond peels are rich in polyphenols such as catechin and epicatechin, which are important anti-free-radical agents, anti-inflammatory compounds, and capable of breaking down cholesterol plaques. This work aims to evaluate the biological and technological activity of a “green” dry aqueous extract [...] Read more.

(1) Background: almond peels are rich in polyphenols such as catechin and epicatechin, which are important anti-free-radical agents, anti-inflammatory compounds, and capable of breaking down cholesterol plaques. This work aims to evaluate the biological and technological activity of a “green” dry aqueous extract from Sicilian almond peels, a waste product of the food industry, and to develop healthy nutraceuticals with natural ingredients. Eudraguard^® Natural is a natural coating polymer chosen to develop atomized formulations that improve the technological properties of the extract. (2) Methods: the antioxidant and free radical scavenger activity of the extract was rated using different methods (DPPH assay, ABTS, ORAC, NO). The metalloproteinases of the extracts (MMP-2 and MMP-9), the enhanced inhibition of the final glycation products, and the effects of the compounds on cell viability were also tested. All pure materials and formulations were characterized using UV, HPLC, FTIR, DSC, and SEM methods. (3) Results: almond peel extract showed appreciable antioxidant and free radical activity with a stronger NO inhibition effect, strong activity on MMP-2, and good antiglycative effects. In light of this, a food supplement with added health value was formulated. Eudraguard^® Natural acted as a swelling substrate by improving extract solubility and dissolution/release (4) Conclusions: almond peel extract has significant antioxidant activity and MMP/AGE inhibition effects, resulting in an optimal candidate to formulate safe microsystems with potential antimetabolic activity. Eudraguard^® Natural is capable of obtaining spray-dried microsystems with an improvement in the extract‘s biological and technological characteristics. It also protects the dry extract from degradation and oxidation, prolonging the shelf life of the final product. Full article

(This article belongs to the Special Issue Recent Advances in the Valorization of Food, Agricultural By-Products and Waste)

► Show Figures

Figure 1

16 pages, 2215 KiB

Open AccessArticle

Synthesis and Biological Evaluation of 2-Substituted Quinazolin-4(3H)-Ones with Antiproliferative Activities

by Maria Karelou, Dionysis Kampasis, Amalia D. Kalampaliki, Leentje Persoons, Andreas Krämer, Dominique Schols, Stefan Knapp, Steven De Jonghe and Ioannis K. Kostakis

Molecules 2023, 28(23), 7912; https://doi.org/10.3390/molecules28237912 - 2 Dec 2023

Cited by 2 | Viewed by 1691

Abstract

Sixteen new 2-substituted quinazolines were synthesized using a straightforward methodology starting from 2-methoxybezoic acid or 3-methoxy-2-naphthoic acid. The anti-proliferative activity of the target compounds was evaluated against nine cancer cell lines. Additionally, all the compounds were screened for their potency and selectivity against [...] Read more.

Sixteen new 2-substituted quinazolines were synthesized using a straightforward methodology starting from 2-methoxybezoic acid or 3-methoxy-2-naphthoic acid. The anti-proliferative activity of the target compounds was evaluated against nine cancer cell lines. Additionally, all the compounds were screened for their potency and selectivity against a panel of 109 kinases and four bromodomains, using Differential Scanning Fluorimetry (DSF). Compound 17 bearing a 2-methoxyphenyl substitution along with a basic side chain displayed a remarkable profile against the majority of the tested cell lines. Full article

(This article belongs to the Special Issue Design, Synthesis and Biological Evaluation of Heterocyclic Compounds)

► Show Figures

Figure 1

19 pages, 2403 KiB

Open AccessCommunication

Systematic Analysis of 2′-O-Alkyl Modified Analogs for Enzymatic Synthesis and Their Oligonucleotide Properties

by Kenta Ishida, Yuuya Kasahara, Hidekazu Hoshino, Takumi Okuda and Satoshi Obika

Molecules 2023, 28(23), 7911; https://doi.org/10.3390/molecules28237911 - 2 Dec 2023

Viewed by 1855

Abstract

Enzymatic oligonucleotide synthesis is used for the development of functional oligonucleotides selected by in vitro selection. Expanding available sugar modifications for in vitro selection helps the functional oligonucleotides to be used as therapeutics reagents. We previously developed a KOD DNA polymerase mutant, KOD [...] Read more.

Enzymatic oligonucleotide synthesis is used for the development of functional oligonucleotides selected by in vitro selection. Expanding available sugar modifications for in vitro selection helps the functional oligonucleotides to be used as therapeutics reagents. We previously developed a KOD DNA polymerase mutant, KOD DGLNK, that enzymatically synthesized fully-LNA- or 2′-O-methyl-modified oligonucleotides. Here, we report a further expansion of the available 2′-O-alkyl-modified nucleotide for enzymatic synthesis by KOD DGLNK. We chemically synthesized five 2′-O-alkyl-5-methyluridine triphosphates and incorporated them into the oligonucleotides. We also enzymatically synthesized a 2′-O-alkyl-modified oligonucleotide with a random region (oligonucleotide libraries). The 2′-O-alkyl-modified oligonucleotide libraries showed high nuclease resistance and a wide range of hydrophobicity. Our synthesized 2′-O-alkyl-modified oligonucleotide libraries provide novel possibilities that can promote the development of functional molecules for therapeutic use. Full article

(This article belongs to the Special Issue Aptamer Generation and Bioapplication)

► Show Figures

Figure 1

16 pages, 2515 KiB

Open AccessReview

Can We Improve Diosmetin Activity? The State-of-the-Art and Promising Research Directions

by Monika Wujec and Marcin Feldo

Molecules 2023, 28(23), 7910; https://doi.org/10.3390/molecules28237910 - 2 Dec 2023

Cited by 3 | Viewed by 2035

Abstract

Diosmetin is a natural substance widely distributed in nature, with documented multidirectional biological effects. The wide spectrum of biological activity of diosmetin gives hope that derivatives of this flavonoid may also be used as drugs or dietary supplements used in many diseases. Modification [...] Read more.

Diosmetin is a natural substance widely distributed in nature, with documented multidirectional biological effects. The wide spectrum of biological activity of diosmetin gives hope that derivatives of this flavonoid may also be used as drugs or dietary supplements used in many diseases. Modification of the structure may, on the one hand, lead to an increase in biological potency, new biological activity, or an increase in solubility and thus bioavailability. This is an important direction of research because the use of pure diosmetin is limited due to its low bioavailability. This work is an attempt to collect information on the possibility of modifying the structure of diosmetin and its impact on biological activity. Full article

(This article belongs to the Special Issue Heterocycles: Design, Synthesis and Biological Evaluation)

► Show Figures

Figure 1

34 pages, 3299 KiB

Open AccessReview

Are There Lipid Membrane-Domain Subtypes in Neurons with Different Roles in Calcium Signaling?

by Alejandro K. Samhan-Arias, Joana Poejo, Dorinda Marques-da-Silva, Oscar H. Martínez-Costa and Carlos Gutierrez-Merino

Molecules 2023, 28(23), 7909; https://doi.org/10.3390/molecules28237909 - 2 Dec 2023

Cited by 5 | Viewed by 3057

Abstract

Lipid membrane nanodomains or lipid rafts are 10–200 nm diameter size cholesterol- and sphingolipid-enriched domains of the plasma membrane, gathering many proteins with different roles. Isolation and characterization of plasma membrane proteins by differential centrifugation and proteomic studies have revealed a remarkable diversity [...] Read more.

Lipid membrane nanodomains or lipid rafts are 10–200 nm diameter size cholesterol- and sphingolipid-enriched domains of the plasma membrane, gathering many proteins with different roles. Isolation and characterization of plasma membrane proteins by differential centrifugation and proteomic studies have revealed a remarkable diversity of proteins in these domains. The limited size of the lipid membrane nanodomain challenges the simple possibility that all of them can coexist within the same lipid membrane domain. As caveolin-1, flotillin isoforms and gangliosides are currently used as neuronal lipid membrane nanodomain markers, we first analyzed the structural features of these components forming nanodomains at the plasma membrane since they are relevant for building supramolecular complexes constituted by these molecular signatures. Among the proteins associated with neuronal lipid membrane nanodomains, there are a large number of proteins that play major roles in calcium signaling, such as ionotropic and metabotropic receptors for neurotransmitters, calcium channels, and calcium pumps. This review highlights a large variation between the calcium signaling proteins that have been reported to be associated with isolated caveolin-1 and flotillin-lipid membrane nanodomains. Since these calcium signaling proteins are scattered in different locations of the neuronal plasma membrane, i.e., in presynapses, postsynapses, axonal or dendritic trees, or in the neuronal soma, our analysis suggests that different lipid membrane-domain subtypes should exist in neurons. Furthermore, we conclude that classification of lipid membrane domains by their content in calcium signaling proteins sheds light on the roles of these domains for neuronal activities that are dependent upon the intracellular calcium concentration. Some examples described in this review include the synaptic and metabolic activity, secretion of neurotransmitters and neuromodulators, neuronal excitability (long-term potentiation and long-term depression), axonal and dendritic growth but also neuronal cell survival and death. Full article

(This article belongs to the Special Issue Themed Issue in Honor of Carlos Gutiérrez Merino: Forty Years of Research Excellence in the Field of Membrane Proteins and Bioenergetics)

► Show Figures

Figure 1

15 pages, 10564 KiB

Open AccessArticle

Efficient Selective Capture of Carbon Dioxide from Nitrogen and Methane Using a Metal-Organic Framework-Based Nanotrap

by Junjie Peng, Chengmin Fu, Jiqin Zhong, Bin Ye, Jing Xiao, Chongxiong Duan and Daofei Lv

Molecules 2023, 28(23), 7908; https://doi.org/10.3390/molecules28237908 - 2 Dec 2023

Cited by 2 | Viewed by 1659

Abstract

Selective carbon capture from exhaust gas and biogas, which mainly involves the separation of CO₂/N₂ and CO₂/CH₄ mixtures, is of paramount importance for environmental and industrial requirements. Herein, we propose an interesting metal-organic framework-based nanotrap, namely ZnAtzCO [...] Read more.

Selective carbon capture from exhaust gas and biogas, which mainly involves the separation of CO₂/N₂ and CO₂/CH₄ mixtures, is of paramount importance for environmental and industrial requirements. Herein, we propose an interesting metal-organic framework-based nanotrap, namely ZnAtzCO₃ (Atz⁻ = 3-amino-1,2,4-triazolate, CO₃²⁻ = carbonate), with a favorable ultramicroporous structure and electrostatic interactions that facilitate efficient capture of CO₂. The structural composition and stability were verified by FTIR, TGA, and PXRD techniques. Particularly, ZnAtzCO₃ demonstrated high CO₂ capacity in a wide range of pressures, with values of 44.8 cm³/g at the typical CO₂ fraction of the flue gas (15 kPa) and 56.0 cm³/g at the CO₂ fraction of the biogas (50 kPa). Moreover, ultrahigh selectivities over CO₂/N₂ (15:85, v:v) and CO₂/CH₄ (50:50, v:v) of 3538 and 151 were achieved, respectively. Molecular simulations suggest that the carbon atom of CO₂ can form strong electrostatic C^δ+···^δ−O-C interactions with four oxygen atoms in the carbonate ligands, while the oxygen atom of CO₂ can interact with the hydrogen atoms in the triazolate ligands through O^δ−···^δ+H-C interactions, which makes ZnAtzCO₃ an optimal nanotrap for CO₂ fixation. Furthermore, breakthrough experiments confirmed excellent real-world separation toward CO₂/N₂ and CO₂/CH₄ mixtures on ZnAtzCO₃, demonstrating its great potential for selective CO₂ capture. Full article

(This article belongs to the Special Issue Zeolites and Porous Materials: Synthesis, Properties and Applications)

► Show Figures

Graphical abstract

22 pages, 4096 KiB

Open AccessArticle

Determination of the Concentration of Heavy Metals in Artisanal Cheeses Produced in the Mexican States of Tabasco and Chiapas

by Francisco Anguebes-Franseschi, Mohamed Abatal, Claudia Alejandra Ucán, Alejandro Ruiz Marín, Francisco Tamayo-Ordoñez, Yunuen Canedo-López, Luis Perez-Reda and Siprian Damás-Damas

Molecules 2023, 28(23), 7907; https://doi.org/10.3390/molecules28237907 - 2 Dec 2023

Viewed by 1501

Abstract

Cheese consumption provides humans with minerals, proteins, carbohydrates, and vitamins. In Mexico, several cheese varieties are produced, each with its texture, scent, and flavor. The artisanal cheeses made in the states of Tabasco and Chiapas—including, among others, the varieties named crema (cream), doble [...] Read more.

Cheese consumption provides humans with minerals, proteins, carbohydrates, and vitamins. In Mexico, several cheese varieties are produced, each with its texture, scent, and flavor. The artisanal cheeses made in the states of Tabasco and Chiapas—including, among others, the varieties named crema (cream), doble crema (double cream), oaxaca, panela, fresco, bola, poro, cotija, and asadero—have a high demand in the domestic and foreign markets. The intensification of anthropic activity in these states causes an increased emission to the environment of contaminants like heavy metals, which could reach human foodstuffs through the food chains. In particular, heavy metal contents in cheeses consumed daily by these states’ local populations might represent a public health risk. Because of that, our objectives in this work were to determine the concentrations of lead, cadmium, nickel, copper, zinc, and iron in artisanal cheeses produced in the states of Tabasco and Chiapas and to determine the values of the hazard quotient (HQ), total hazard quotient (THQ), and cancer risk total (CRT) for adult and young men and women. The results of our analyses of cheese samples from the states of Tabasco and Chiapas showed that the average concentrations (mg kg⁻¹) of cadmium (0.0023 ± 0.002, 0.0023 ± 0.002 mg kg⁻¹, respectively, for each state), lead (0.0047 ± 0.00, 0.0051 ± 0.002), nickel (0.0039 ± 0.0046, 0.0031 ± 0.0039), copper (0.0199 ± 0.021, 0.0202 ± 0.022), zinc (0.1611 ± 0.18, 0.194 ± 0.21), and iron (61.84 ± 4.23, 65.76 ± 6.61 mg kg⁻¹), the first three values lower than the limits established by the FAO/WHO and Codex Alimentarius. The value of THQ that we obtained was less than one, and that of CRT was within the limits established by the US-EPA, which means that the consumption of artisanal cheeses from Tabasco and Chiapas by humans does not imply a risk of disease or cancer. Full article

(This article belongs to the Special Issue Recent Advances and Future Challenges in Food Analysis II)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Molecules, Volume 28, Issue 23 (December-1 2023) – 257 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI