Journal Description
Molecules
Molecules
is the leading international, peer-reviewed, open access journal of chemistry. Molecules is published semimonthly online by MDPI. The International Society of Nucleosides, Nucleotides & Nucleic Acids (IS3NA), the Spanish Society of Medicinal Chemistry (SEQT) and the International Society of Heterocyclic Chemistry (ISHC) are affiliated with Molecules and their members receive a discount on the article processing charges.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), PubMed, MEDLINE, PMC, Reaxys, CaPlus / SciFinder, MarinLit, AGRIS, and other databases.
- Journal Rank: JCR - Q2 (Chemistry, Multidisciplinary) / CiteScore - Q1 (Chemistry (miscellaneous))
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.6 days after submission; acceptance to publication is undertaken in 2.7 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
- Sections: published in 26 topical sections.
- Testimonials: See what our editors and authors say about Molecules.
- Companion journals for Molecules include: Foundations and Photochem.
Impact Factor:
4.6 (2022);
5-Year Impact Factor:
4.9 (2022)
Latest Articles
The Biological Activity of Ganoderma lucidum on Neurodegenerative Diseases: The Interplay between Different Active Compounds and the Pathological Hallmarks
Molecules 2024, 29(11), 2516; https://doi.org/10.3390/molecules29112516 (registering DOI) - 26 May 2024
Abstract
Neurodegenerative diseases represent a cluster of conditions characterized by the progressive degeneration of the structure and function of the nervous system. Despite significant advancements in understanding these diseases, therapeutic options remain limited. The medicinal mushroom Ganoderma lucidum has been recognized for its comprehensive
[...] Read more.
Neurodegenerative diseases represent a cluster of conditions characterized by the progressive degeneration of the structure and function of the nervous system. Despite significant advancements in understanding these diseases, therapeutic options remain limited. The medicinal mushroom Ganoderma lucidum has been recognized for its comprehensive array of bioactive compounds with anti-inflammatory and antioxidative effects, which possess potential neuroprotective properties. This literature review collates and examines the existing research on the bioactivity of active compounds and extracts from Ganoderma lucidum in modulating the pathological hallmarks of neurodegenerative diseases. The structural information and preparation processes of specific components, such as individual ganoderic acids and unique fractions of polysaccharides, are presented in detail to facilitate structure–activity relationship research and scale up the investigation of in vivo pharmacology. The mechanisms of these components against neurodegenerative diseases are discussed on multiple levels and elaborately categorized in different patterns. It is clearly presented from the patterns that most polysaccharides of Ganoderma lucidum possess neurotrophic effects, while ganoderic acids preferentially target specific pathogenic proteins as well as regulating autophagy. Further clinical trials are necessary to assess the translational potential of these components in the development of novel multi-target drugs for neurodegenerative diseases.
Full article
(This article belongs to the Special Issue Structural Analysis and Biological Evaluation of Compounds from Fungi—2nd Edition)
►
Show Figures
Open AccessFeature PaperReview
Encapsulation in Alginates Hydrogels and Controlled Release: An Overview
by
Camille Colin, Emma Akpo, Aurélie Perrin, David Cornu and Julien Cambedouzou
Molecules 2024, 29(11), 2515; https://doi.org/10.3390/molecules29112515 (registering DOI) - 26 May 2024
Abstract
This review aims to gather the current state of the art on the encapsulation methods using alginate as the main polymeric material in order to produce hydrogels ranging from the microscopic to macroscopic sizes. The use of alginates as an encapsulation material is
[...] Read more.
This review aims to gather the current state of the art on the encapsulation methods using alginate as the main polymeric material in order to produce hydrogels ranging from the microscopic to macroscopic sizes. The use of alginates as an encapsulation material is of growing interest, as it is fully bio-based, bio-compatible and bio-degradable. The field of application of alginate encapsulation is also extremely broad, and there is no doubt it will become even broader in the near future considering the societal demand for sustainable materials in technological applications. In this review, alginate’s main properties and gelification mechanisms, as well as some factors influencing this mechanism, such as the nature of the reticulation cations, are first investigated. Then, the capacity of alginate gels to release matter in a controlled way, from small molecules to micrometric compounds, is reported and discussed. The existing techniques used to produce alginates beads, from the laboratory scale to the industrial one, are further described, with a consideration of the pros and cons with each techniques. Finally, two examples of applications of alginate materials are highlighted as representative case studies.
Full article
(This article belongs to the Special Issue Recent Advances in Porous Materials)
Open AccessArticle
A Convenient In Situ Preparation of Cu2ZnSnS4–Anatase Hybrid Nanocomposite for Photocatalysis/Photoelectrochemical Water-Splitting Hydrogen Production
by
Ke-Xian Li, Cai-Hong Li, Hao-Yan Shi, Rui Chen, Ao-Sheng She, Yang Yang, Xia Jiang, Yan-Xin Chen and Can-Zhong Lu
Molecules 2024, 29(11), 2514; https://doi.org/10.3390/molecules29112514 (registering DOI) - 26 May 2024
Abstract
This study details the rational design and synthesis of Cu2ZnSnS4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS–A heterojunctions. As the
[...] Read more.
This study details the rational design and synthesis of Cu2ZnSnS4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS–A heterojunctions. As the concentration of titanium dioxide (TiO2) varied, the morphology of CZTS shifted from floral patterns to sheet-like structures. The resulting CZTS–A heterostructures underwent comprehensive characterization through photoelectrochemical response assessments, optical measurements, and electrochemical impedance spectroscopy analyses. Detailed photoelectrochemical (PEC) investigations demonstrated notable enhancements in photocurrent density and incident photon-to-electron conversion efficiency (IPCE). Compared to pure anatase electrodes, the optimized CZTS–A heterostructures exhibited a seven-fold increase in photocurrent density and reached a hydrogen production efficiency of 1.1%. Additionally, the maximum H2 production rate from these heterostructures was 11-times greater than that of pure anatase and 250-times higher than the original CZTS after 2 h of irradiation. These results underscore the enhanced PEC performance of CZTS–A heterostructures, highlighting their potential as highly efficient materials for solar water splitting. Integrating Cu2ZnSnS4 nanoparticles (NPs) within TiO2 (anatase) heterostructures implied new avenues for developing earth-abundant and cost-effective photocatalytic systems for renewable energy applications.
Full article
(This article belongs to the Section Inorganic Chemistry)
►▼
Show Figures
Graphical abstract
Open AccessArticle
Material Composition Characteristics of Aspergillus cristatus under High Salt Stress through LC–MS Metabolomics
by
Luyi Xie, Lihong Zhou, Rongrong Zhang, Hang Zhou and Yi Yang
Molecules 2024, 29(11), 2513; https://doi.org/10.3390/molecules29112513 (registering DOI) - 26 May 2024
Abstract
►▼
Show Figures
Aspergillus cristatus is a crucial edible fungus used in tea fermentation. In the industrial fermentation process, the fungus experiences a low to high osmotic pressure environment. To explore the law of material metabolism changes during osmotic pressure changes, NaCl was used here to
[...] Read more.
Aspergillus cristatus is a crucial edible fungus used in tea fermentation. In the industrial fermentation process, the fungus experiences a low to high osmotic pressure environment. To explore the law of material metabolism changes during osmotic pressure changes, NaCl was used here to construct different osmotic pressure environments. Liquid chromatography–mass spectrometry (LC–MS) combined with multivariate analysis was performed to analyze the distribution and composition of A. cristatus under different salt concentrations. At the same time, the in vitro antioxidant activity was evaluated. The LC–MS metabolomics analysis revealed significant differences between three A. cristatus mycelium samples grown on media with and without NaCl concentrations of 8% and 18%. The contents of gibberellin A3, A124, and prostaglandin A2 related to mycelial growth and those of arabitol and fructose-1,6-diphosphate related to osmotic pressure regulation were significantly reduced at high NaCl concentrations. The biosynthesis of energy-related pantothenol and pantothenic acid and antagonism-related fluvastatin, aflatoxin, and alternariol significantly increased at high NaCl concentrations. Several antioxidant capacities of A. cristatus mycelia were directly related to osmotic pressure and exhibited a significant downward trend with an increase in environmental osmotic pressure. The aforementioned results indicate that A. cristatus adapts to changes in salt concentration by adjusting their metabolite synthesis. At the same time, a unique set of strategies was developed to cope with high salt stress, including growth restriction, osmotic pressure balance, oxidative stress response, antioxidant defense, and survival competition.
Full article
Figure 1
Open AccessFeature PaperArticle
Improving Water-Based Drilling Mud Performance Using Biopolymer Gum: Integrating Experimental and Machine Learning Techniques
by
Mobeen Murtaza, Zeeshan Tariq, Muhammad Shahzad Kamal, Azeem Rana, Tawfik A. Saleh, Mohamed Mahmoud, Sulaiman A. Alarifi and Nadeem Ahmed Syed
Molecules 2024, 29(11), 2512; https://doi.org/10.3390/molecules29112512 (registering DOI) - 26 May 2024
Abstract
Drilling through shale formations can be expensive and time-consuming due to the instability of the wellbore. Further, there is a need to develop inhibitors that are environmentally friendly. Our study discovered a cost-effective solution to this problem using Gum Arabic (ArG). We evaluated
[...] Read more.
Drilling through shale formations can be expensive and time-consuming due to the instability of the wellbore. Further, there is a need to develop inhibitors that are environmentally friendly. Our study discovered a cost-effective solution to this problem using Gum Arabic (ArG). We evaluated the inhibition potential of an ArG clay swelling inhibitor and fluid loss controller in water-based mud (WBM) by conducting a linear swelling test, capillary suction timer test, and zeta potential, fluid loss, and rheology tests. Our results displayed a significant reduction in linear swelling of bentonite clay (Na-Ben) by up to 36.1% at a concentration of 1.0 wt. % ArG. The capillary suction timer (CST) showed that capillary suction time also increased with the increase in the concentration of ArG, which indicates the fluid-loss-controlling potential of ArG. Adding ArG to the drilling mud prominently decreased fluid loss by up to 50%. Further, ArG reduced the shear stresses of the base mud, showing its inhibition and friction-reducing effect. These findings suggest that ArG is a strong candidate for an alternate green swelling inhibitor and fluid loss controller in WBM. Introducing this new green additive could significantly reduce non-productive time and costs associated with wellbore instability while drilling. Further, a dynamic linear swelling model, based on machine learning (ML), was created to forecast the linear swelling capacity of clay samples treated with ArG. The ML model proposed demonstrates exceptional accuracy (R2 score = 0.998 on testing) in predicting the swelling properties of ArG in drilling mud.
Full article
(This article belongs to the Special Issue Recent Insights into Biopolymer Processing, from Preparation to Fundamental Properties and Industrial Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
Effect of Organic Acid-Aided Extraction on Characteristics and Functional Properties of Pectin from Cannabis sativa L.
by
Nopparat Prabsangob, Sasithorn Hangsalad and Thepkunya Harnsilawat
Molecules 2024, 29(11), 2511; https://doi.org/10.3390/molecules29112511 (registering DOI) - 26 May 2024
Abstract
The extraction of cannabinoids from the inflorescence and leaves of Cannabis sativa L. is gaining interest from researchers, in addition to addressing the under-utilization of the by-products in the stems and roots of the trees. The present study investigated the recovery of pectin
[...] Read more.
The extraction of cannabinoids from the inflorescence and leaves of Cannabis sativa L. is gaining interest from researchers, in addition to addressing the under-utilization of the by-products in the stems and roots of the trees. The present study investigated the recovery of pectin from the left-over parts of hemp tress using an eco-friendly method with the aid of organic acids. Different cannabis cultivars—Chalotte’s Angels (CHA) and Hang-Krarog (HKR)—were used as plant materials. The stems of both cannabis cultivars contained more pectin than the roots, and tartaric acid-aided extraction provided higher yields than from citric acid. Extracting the acid solution affected some characteristics, thereby differentiating the functional properties of the derived pectin. Extraction using tartaric acid provided pectin with a higher galacturonic acid content, whereas pectin with a higher methylation degree could be prepared using citric acid. The pectin samples extracted from the stems of CHA (P-CHA) and HKR (P-HKR) had low methoxyl pectin. P-CHA had better free radical scavenging capability, whereas P-HKR showed more potent reducibility. Considering the functional properties, P-CHA showed greater emulsion formability and foaming activity, whereas P-HKR possessed a better thickening effect. The present work suggests the feasible utilization of P-CHA and P-HKR as food additives with bioactivity.
Full article
(This article belongs to the Section Food Chemistry)
►▼
Show Figures
Figure 1
Open AccessArticle
New Triazole-Isoxazole Hybrids as Antibacterial Agents: Design, Synthesis, Characterization, In Vitro, and In Silico Studies
by
Rachid Bouzammit, Salim Belchkar, Mohamed El fadili, Youssra Kanzouai, Somdutt Mujwar, Mohammed M. Alanazi, Mohammed Chalkha, Asmae Nakkabi, Mohamed Bakhouch, Emese Gal, Luiza Ioana Gaina and Ghali al houari
Molecules 2024, 29(11), 2510; https://doi.org/10.3390/molecules29112510 (registering DOI) - 26 May 2024
Abstract
Novel isoxazole–triazole conjugates have been efficiently synthesized using 3-formylchromone as starting material according to a multi-step synthetic approach. The structures of the target conjugates and intermediate products were characterized by standard spectroscopic techniques (1H NMR and 13C NMR) and confirmed
[...] Read more.
Novel isoxazole–triazole conjugates have been efficiently synthesized using 3-formylchromone as starting material according to a multi-step synthetic approach. The structures of the target conjugates and intermediate products were characterized by standard spectroscopic techniques (1H NMR and 13C NMR) and confirmed by mass spectrometry (MS). The all-synthesized compounds were screened for their antibacterial activity against three ATCC reference strains, namely Staphylococcus aureus ATCC 25923, Staphylococcus aureus ATCC BAA-44, and Escherichia coli ATCC 25922 as well as one strain isolated from the hospital environment Pseudomonas aeruginosa. The findings indicate that conjugate 7b exhibits a stronger antibacterial response against the tested Escherichia coli ATCC 25922 and Pseudomonas aeruginosa pathogenic strains compared to the standard antibiotics. Furthermore, hybrid compound 7b proved to have a bactericidal action on the Escherichia coli ATCC 25922 strain, as evidenced by the results of the MBC determination. Moreover, the ADMET pharmacokinetic characteristics revealed a favorable profile for the examined compound, as well as a good level of oral bioavailability. Molecular docking and molecular dynamics simulations were performed to explore the inhibition mechanism and binding energies of conjugate 7b with the proteins of Escherichia coli and Pseudomonas aeruginosa bacterial strains. The in silico results corroborated the data observed in the in vitro evaluation for compound 7b.
Full article
(This article belongs to the Special Issue Design, Synthesis and Applications of Bioactive Compounds)
►▼
Show Figures
Figure 1
Open AccessArticle
Effect of Cap Management Frequency on the Phenolic, Chromatic, and Sensory Composition of Cabernet Sauvignon Wines from the Central Coast of California over Two Vintages
by
L. Federico Casassa, Isabelle LoMonaco, Marcel Velasco and Dimos D. Papageorgas
Molecules 2024, 29(11), 2509; https://doi.org/10.3390/molecules29112509 (registering DOI) - 26 May 2024
Abstract
Cabernet Sauvignon from the California Paso Robles AVA was processed with a contrasting array of cap management frequencies, consisting of punch-down (PD) frequencies (0, 1, 2, and 3 PD/day) over two vintages, one of which the fruit was harvested at two contrasting maturity
[...] Read more.
Cabernet Sauvignon from the California Paso Robles AVA was processed with a contrasting array of cap management frequencies, consisting of punch-down (PD) frequencies (0, 1, 2, and 3 PD/day) over two vintages, one of which the fruit was harvested at two contrasting maturity levels. Wines followed with up to 3 years of bottle aging for basic and phenolic chemistry, and the wines of the second harvest of 2020 were submitted to sensory analysis. There were almost non-existent effects due to the frequency of punch downs on parameters such as ethanol, pH, titratable acidity, lactic acid, and glucose + fructose. In 2019, the chromatic differences between different PD regimes were subtle, and minor effects of the punch-down frequency were observed for tannins and total phenolics. During the early stages of alcoholic fermentation, higher levels of all anthocyanin classes were observed in 1 PD wines and the lowest levels in 0 PD wines. The anthocyanin content of the wines of the first harvest (unripe) was 27% higher than that of the wines of the second harvest (ripe), but these differences disappeared after 3 years of bottle aging irrespective of the vintage and harvest date. Acylated anthocyanins were preferentially lost during aging, especially in 2019 wines and, to a lesser extent, in 2020 wines. In 2020, the polymeric pigment content of the wines of the second harvest was higher than in the wines of the first harvest, with 3 PD wines showing higher polymeric pigments and yellow hues than 0 and 2 PD wines after 3 years of bottle aging. Sensory analysis of the second harvest of the 2020 wines showed that the wines of all four PD regimes were perceived as drying, signifying they were perceived as equally astringent, which is consistent with comparable tannin levels on said wines. The perception of bitterness increased with the frequency of punch downs; thus, 3 PD wines showed the highest bitterness perception. It was concluded that in sufficiently warm fermentations and small volumes, phenolic extraction occurs regardless of fruit maturity and under conditions of minimum mixing.
Full article
(This article belongs to the Special Issue The Impact of Advances in Fermentation Processes on the Chemical Composition of the Final Product)
►▼
Show Figures
Figure 1
Open AccessArticle
Qualitative Analysis of Nitrogen and Sulfur Compounds in Vacuum Gas Oils via Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry
by
Morio Ueda, Jongbeom Lee, Hyeonseok Yi, Gang-Ho Lee, Yu-Jin Kim, Geon-Hee Kim, Kyeongseok Oh, Seong-Ho Yoon, Koji Nakabayashi and Joo-Il Park
Molecules 2024, 29(11), 2508; https://doi.org/10.3390/molecules29112508 (registering DOI) - 26 May 2024
Abstract
Analysis of the heavy fractions in crude oil has been important in petroleum industries. It is well known that heavy fractions such as vacuum gas oils (VGOs) include heteroatoms, of which sulfur and nitrogen are often characterized in many cases. We conducted research
[...] Read more.
Analysis of the heavy fractions in crude oil has been important in petroleum industries. It is well known that heavy fractions such as vacuum gas oils (VGOs) include heteroatoms, of which sulfur and nitrogen are often characterized in many cases. We conducted research regarding the molecular species analysis of VGOs. Further refine processes using VGOs are becoming important when considering carbon recycling. In this work, we attempted to classify compounds within VGOs provided by Kuwait Institute for Scientific Research. Two VGOs were priorly distillated from Kuwait Export crude and Lower Fars crude. Quantitative analysis was performed mainly using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOFMS). MALDI-TOF-MS has been developed for analyzing high-molecular-weight compounds such as polymer and biopolymers. As matrix selection is one of the most important aspects in MALDI-TOFMS, the careful selection of a matrix was firstly evaluated, followed by analysis using a Kendrick plot with nominal mass series (z*). The objective was to evaluate if this work could provide an effective classification of VGOs compounds. The Kendrick plot is a well-known method for processing mass data. The difference in the Kendrick mass defect (KMD) between CnH2n−14S and CnH2n−20O is only 0.0005 mass units, which makes it difficult in general to distinguish these compounds. However, since the z* value showed effective differences during the classification of these compounds, qualitative analysis could be possible. The analysis using nominal mass series showed the potential to be used as an effective method in analyzing heavy fractions.
Full article
(This article belongs to the Special Issue (Mass Spectrometric) Non Target Screening–Techniques and Strategies: Volume II)
►▼
Show Figures
Figure 1
Open AccessArticle
4-Vinyl Guaiacol: A Key Intermediate for Biobased Polymers
by
Elena Rigo, Cédric Totée, Vincent Ladmiral, Sylvain Caillol and Patrick Lacroix-Desmazes
Molecules 2024, 29(11), 2507; https://doi.org/10.3390/molecules29112507 (registering DOI) - 25 May 2024
Abstract
In order to contribute to the shift from petro-based chemistry to biobased chemistry, necessary to minimize the environmental impacts of the chemical industry, 2-methoxy-4-vinylphenol (4-vinyl guaiacol, 4VG) was used to synthesize a platform of biobased monomers. Thus, nine biobased monomers were successfully prepared.
[...] Read more.
In order to contribute to the shift from petro-based chemistry to biobased chemistry, necessary to minimize the environmental impacts of the chemical industry, 2-methoxy-4-vinylphenol (4-vinyl guaiacol, 4VG) was used to synthesize a platform of biobased monomers. Thus, nine biobased monomers were successfully prepared. The synthesis procedures were investigated through the green metrics calculations in order to quantify the sustainability of our approaches. Their radical homopolymerization in toluene solution initiated by 2,2′-azobis(2-methylpropionitrile) (AIBN) was studied and the effect of residual 4VG as a radical inhibitor on the kinetics of polymerization was also explored. The new homopolymers were characterized by proton nuclear magnetic resonance (1H-NMR) spectroscopy, size exclusion chromatography and thermal analyses (dynamical scanning calorimetry DSC, thermal gravimetric analysis TGA). By varying the length of the alkyl ester or ether group of the 4VG derivatives, homopolymers with Tg ranging from 117 °C down to 5 °C were obtained. These new biobased monomers could be implemented in radical copolymerization as substitutes to petro-based monomers to decrease the carbon footprint of the resulting copolymers for various applications.
Full article
(This article belongs to the Special Issue Sustainable Chemistry in France 2.0)
►▼
Show Figures
Figure 1
Open AccessArticle
Ferrocene Bis(Sulfonate) Salt as Redoxmer for Fast and Steady Redox Flow Desalination
by
Rongxuan Xie, Briana R. Schrage, Junhua Jiang, Christopher J. Ziegler and Zhenmeng Peng
Molecules 2024, 29(11), 2506; https://doi.org/10.3390/molecules29112506 (registering DOI) - 25 May 2024
Abstract
Desalination is considered a promising solution to alleviate water shortages, yet current methods are often restricted, due to challenges like high energy consumption, significant cost, or limited desalination capacity. In this study, we present a novel approach of redox flow desalination (RFD) utilizing
[...] Read more.
Desalination is considered a promising solution to alleviate water shortages, yet current methods are often restricted, due to challenges like high energy consumption, significant cost, or limited desalination capacity. In this study, we present a novel approach of redox flow desalination (RFD) utilizing the highly aqueous-soluble and reversible redox-active compound, potassium 1,1′-bis(sulfonate) ferrocene (1,1′-FcDS). This water-soluble organic compound yielded stable and rapid desalination, sustaining extended operation without notable decay and achieving an impressive desalination rate of up to 457.5 mmol·h−1·m−2 and energy consumption as low as 40.2 kJ·molNaCl−1. Specifically, the RFD device effectively desalinated a 50 mM NaCl solution to potable standards within 6000 s using 1,1′-FcDS. It maintained an average energy consumption of 178.16 kJ·molNaCl−1 and exhibited negligible deterioration in desalination rate, energy efficiency, and charge efficiency throughout a rigorous 12,000 s cycling test. Furthermore, the versatility of this method was demonstrated by effectively treating saline water with varying initial concentrations from 10 mM to 50 mM, showcasing its potential across a broad spectrum of applications.
Full article
(This article belongs to the Special Issue Exclusive Feature Papers in Electrochemistry)
►▼
Show Figures
Figure 1
Open AccessArticle
Preparation of UiO-66 MOF-Bonded Porous-Layer Open-Tubular Columns Using an In Situ Growth Approach for Gas Chromatography
by
Khadejah D. Otaif, Ahmed-Yacine Badjah-Hadj-Ahmed and Zeid Abdullah ALOthman
Molecules 2024, 29(11), 2505; https://doi.org/10.3390/molecules29112505 (registering DOI) - 25 May 2024
Abstract
The thermally stable zirconium-based MOF, UiO-66, was employed for the preparation of bonded porous‑layer open‑tubular (PLOT) GC columns. The synthesis included the in situ growth of the UiO-66 film on the inner wall of the capillary through a one-step solvothermal procedure. SEM–EDX analysis
[...] Read more.
The thermally stable zirconium-based MOF, UiO-66, was employed for the preparation of bonded porous‑layer open‑tubular (PLOT) GC columns. The synthesis included the in situ growth of the UiO-66 film on the inner wall of the capillary through a one-step solvothermal procedure. SEM–EDX analysis revealed the formation of a thin, continuous, uniform, and compact layer of UiO-66 polycrystals on the functionalized inner wall of the column. The average polarity (ΔIav = 700) and the McReynolds constants reflected the polar nature of the UiO-66 stationary phase. Several mixtures of small organic compounds and real samples were used to evaluate the separation performance of the fabricated columns. Linear alkanes from n-pentane to n-decane were baseline separated within 1.35 min. Also, a series of six n-alkylbenzenes (C3–C8) were separated within 3 min with a minimum resolution of 3.09, whereas monohalobenzene mixtures were separated at 220 °C within 14s. UiO-66 PLOT columns are ideally suited for the isothermal separation of chlorobenzene structural isomers at 210 °C within 45 s with Rs ≥ 1.37. The prepared column featured outstanding thermal stability (up to 450 °C) without any observed bleeding or significant impact on its performance. This feature enabled the analysis of various petroleum-based samples.
Full article
(This article belongs to the Topic Advances in Spectroscopic and Chromatographic Techniques)
►▼
Show Figures
Graphical abstract
Open AccessArticle
Upregulated Palmitoleate and Oleate Production in Escherichia coli Promotes Gentamicin Resistance
by
Guozhu Ye, Lvyuan Fan, Yuhong Zheng, Xu Liao, Qiansheng Huang and Yubin Su
Molecules 2024, 29(11), 2504; https://doi.org/10.3390/molecules29112504 (registering DOI) - 25 May 2024
Abstract
Metabolic reprogramming mediates antibiotic efficacy. However, metabolic adaptation of microbes evolving from antibiotic sensitivity to resistance remains undefined. Therefore, untargeted metabolomics was conducted to unveil relevant metabolic reprogramming and potential intervention targets involved in gentamicin resistance. In total, 61 metabolites and 52 metabolic
[...] Read more.
Metabolic reprogramming mediates antibiotic efficacy. However, metabolic adaptation of microbes evolving from antibiotic sensitivity to resistance remains undefined. Therefore, untargeted metabolomics was conducted to unveil relevant metabolic reprogramming and potential intervention targets involved in gentamicin resistance. In total, 61 metabolites and 52 metabolic pathways were significantly altered in gentamicin-resistant E. coli. Notably, the metabolic reprogramming was characterized by decreases in most metabolites involved in carbohydrate and amino acid metabolism, and accumulation of building blocks for nucleotide synthesis in gentamicin-resistant E. coli. Meanwhile, fatty acid metabolism and glycerolipid metabolism were also significantly altered in gentamicin-resistant E. coli. Additionally, glycerol, glycerol-3-phosphate, palmitoleate, and oleate were separately defined as the potential biomarkers for identifying gentamicin resistance in E. coli. Moreover, palmitoleate and oleate could attenuate or even abolished killing effects of gentamicin on E. coli, and separately increased the minimum inhibitory concentration of gentamicin against E. coli by 2 and 4 times. Furthermore, palmitoleate and oleate separately decreased intracellular gentamicin contents, and abolished gentamicin-induced accumulation of reactive oxygen species, indicating involvement of gentamicin metabolism and redox homeostasis in palmitoleate/oleate-promoted gentamicin resistance in E. coli. This study identifies the metabolic reprogramming, potential biomarkers and intervention targets related to gentamicin resistance in bacteria.
Full article
(This article belongs to the Section Analytical Chemistry)
►▼
Show Figures
Figure 1
Open AccessArticle
Baicalin and Baicalein Enhance Cytotoxicity, Proapoptotic Activity, and Genotoxicity of Doxorubicin and Docetaxel in MCF-7 Breast Cancer Cells
by
Joanna Bernasinska-Slomczewska, Pawel Hikisz, Anna Pieniazek and Aneta Koceva-Chyla
Molecules 2024, 29(11), 2503; https://doi.org/10.3390/molecules29112503 (registering DOI) - 25 May 2024
Abstract
Breast cancer is a major health concern and the leading cause of death among women worldwide. Standard treatment often involves surgery, radiotherapy, and chemotherapy, but these come with side effects and limitations. Researchers are exploring natural compounds like baicalin and baicalein, derived from
[...] Read more.
Breast cancer is a major health concern and the leading cause of death among women worldwide. Standard treatment often involves surgery, radiotherapy, and chemotherapy, but these come with side effects and limitations. Researchers are exploring natural compounds like baicalin and baicalein, derived from the Scutellaria baicalensis plant, as potential complementary therapies. This study investigated the effects of baicalin and baicalein on the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel, commonly used chemotherapeutic drugs for breast cancer. The analysis included breast cancer cells (MCF-7) and human endothelial cells (HUVEC-ST), to assess potential effects on healthy tissues. We have found that baicalin and baicalein demonstrated cytotoxicity towards both cell lines, with more potent effects observed in baicalein. Both flavonoids, baicalin (167 µmol/L) and baicalein (95 µmol/L), synergistically enhanced the cytotoxic, proapoptotic, and genotoxic activity of doxorubicin and docetaxel in breast cancer cells. In comparison, their effects on endothelial cells were mixed and depended on concentration and time. The results suggest that baicalin and baicalein might be promising complementary agents to improve the efficacy of doxorubicin and docetaxel anticancer activity. However, further research is needed to validate their safety and efficacy in clinical trials.
Full article
(This article belongs to the Special Issue Natural Products in Anticancer Activity)
►▼
Show Figures
Figure 1
Open AccessArticle
Transformation of Silicate Ions into Silica under the Influence of Acid on the Structure of Serpentinite
by
Abdrazak Auyeshov, Kazhymuhan Arynov, Chaizada Yeskibayeva, Aizhan Dikanbayeva, Darkhan Auyeshov and Yerkebulan Raiymbekov
Molecules 2024, 29(11), 2502; https://doi.org/10.3390/molecules29112502 (registering DOI) - 25 May 2024
Abstract
The process of transformation of the silicate components of the crystal lattice structure of chrysotile during its quantitative interaction with aqueous solutions containing various stoichiometrically required amounts of sulfuric acid (SRA H2SO4) calculated with respect to the magnesium content
[...] Read more.
The process of transformation of the silicate components of the crystal lattice structure of chrysotile during its quantitative interaction with aqueous solutions containing various stoichiometrically required amounts of sulfuric acid (SRA H2SO4) calculated with respect to the magnesium content in the composition of chrysotile is investigated. It has been shown by IR spectroscopic, X-ray phase, thermal and chemical methods of investigation and analysis that, with quantitative interactions of chrysotile and sulfuric acid, first of all, the “brucite layer” of the molecular structural structure of chrysotile is exposed to acid at SRA H2SO4 = 0.1–0.3. As a result of ion exchange processes, acidic silanol (≡Si–O–H) or disilanol (=Si=(O–H)2) bonds are formed. These acid groups form one-dimensional silicate chains with transverse bridges (≡Si–O–Si≡), where the angles (Si–O–Si = 180°C) straighten, which are recorded in the IR spectra in the region of characteristic absorption of 1220–1250 cm−1 silica. The association of the resulting acid groups into silicate chains, dimers, and trimers with transverse bridges, leads to the appearance of colloidal silica particles in the system, which cause some inhibition of the dissolution of layered magnesium hydrosilicate in sulfuric acid solutions containing H2SO4˃ 0.3 SRA.
Full article
Open AccessArticle
Design, Synthesis, Antifungal Activity, and 3D-QSAR Study of Novel Quinoxaline-2-Oxyacetate Hydrazide
by
Peng Teng, Yufei Li, Ruoyu Fang, Yuchuan Zhu, Peng Dai and Weihua Zhang
Molecules 2024, 29(11), 2501; https://doi.org/10.3390/molecules29112501 (registering DOI) - 25 May 2024
Abstract
Plant pathogenic fungi pose a major threat to global food security, ecosystem services, and human livelihoods. Effective and broad-spectrum fungicides are needed to combat these pathogens. In this study, a novel antifungal 2-oxyacetate hydrazide quinoxaline scaffold as a simple analogue was designed and
[...] Read more.
Plant pathogenic fungi pose a major threat to global food security, ecosystem services, and human livelihoods. Effective and broad-spectrum fungicides are needed to combat these pathogens. In this study, a novel antifungal 2-oxyacetate hydrazide quinoxaline scaffold as a simple analogue was designed and synthesized. Their antifungal activities were evaluated against Botrytis cinerea (B. cinerea), Altemaria solani (A. solani), Gibberella zeae (G. zeae), Rhizoctonia solani (R. solani), Colletotrichum orbiculare (C. orbiculare), and Alternaria alternata (A. alternata). These results demonstrated that most compounds exhibited remarkable inhibitory activities and possessed better efficacy than ridylbacterin, such as compound 15 (EC50 = 0.87 μg/mL against G. zeae, EC50 = 1.01 μg/mL against C. orbiculare) and compound 1 (EC50 = 1.54 μg/mL against A. alternata, EC50 = 0.20 μg/mL against R. solani). The 3D-QSAR analysis of quinoxaline-2-oxyacetate hydrazide derivatives has provided new insights into the design and optimization of novel antifungal drug molecules based on quinoxaline.
Full article
(This article belongs to the Special Issue Research and Development of Antibacterial and Antitumor Drugs)
►▼
Show Figures
Graphical abstract
Open AccessArticle
Synthesis of Boronate Affinity-Based Oriented Dummy Template-Imprinted Magnetic Nanomaterials for Rapid and Efficient Solid-Phase Extraction of Ellagic Acid from Food
by
Daojin Li, Na Tang and Xiping Tian
Molecules 2024, 29(11), 2500; https://doi.org/10.3390/molecules29112500 (registering DOI) - 25 May 2024
Abstract
Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of
[...] Read more.
Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of EA would determine its efficacy. Therefore, the accurate analysis of EA content can provide more information for the scientific consumption of EA-rich foods and cosmetics. Nevertheless, the analysis of EA in these samples is challenging due to the low concentration level and the presence of interfering components with high abundance. Molecularly imprinted polymers are highly efficient pretreatment materials in achieving specific recognition of target molecules. However, the traditional template molecule (EA) could not be absolutely removed. Hence, template leakage continues to occur during the sample preparation process, leading to a lack of accuracy in the quantification of EA in actual samples, particularly for trace analytes. In addition, another drawback of EA as an imprinting template is that EA possesses poor solubility and a high price. Gallic acid (GA), called dummy templates, was employed for the synthesis of MIPs as a solution to these challenges. The approach used in this study was boronate affinity-based oriented surface imprinting. The prepared dummy-imprinted nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((4.89 ± 0.46) × 10−5 M), high binding capacity (6.56 ± 0.35 mg/g), fast kinetics (6 min), and low binding pH (pH 5.0) toward EA. The reproducibility of the dummy-imprinted nanoparticles was satisfactory. The dummy-imprinted nanoparticles could still be reused even after six adsorption–desorption cycles. In addition, the recoveries of the proposed method for EA at three spiked levels of analysis in strawberry and pineapple were 91.0–106.8% and 93.8–104.0%, respectively, which indicated the successful application to real samples.
Full article
(This article belongs to the Section Analytical Chemistry)
►▼
Show Figures
Figure 1
Open AccessArticle
Long-Term Polyethylene (Bio)Degradation in Landfill: Environmental and Human Health Implications from Comprehensive Analysis
by
Vladyslav Redko, Lidia Wolska, Ewa Olkowska, Maciej Tankiewicz and Monika Cieszyńska-Semenowicz
Molecules 2024, 29(11), 2499; https://doi.org/10.3390/molecules29112499 (registering DOI) - 25 May 2024
Abstract
This study investigates the process of long-term (bio)degradation of polyethylene (PE) in an old municipal waste landfill (MWL) and its implications for environmental and human health. Advanced techniques, such as ICP–ES/MS and IC–LC, were used to analyze heavy metals and anions/cations, demonstrating significant
[...] Read more.
This study investigates the process of long-term (bio)degradation of polyethylene (PE) in an old municipal waste landfill (MWL) and its implications for environmental and human health. Advanced techniques, such as ICP–ES/MS and IC–LC, were used to analyze heavy metals and anions/cations, demonstrating significant concentration deviations from control samples. The soil’s chemical composition revealed numerous hazardous organic compounds, further indicating the migration of additives from PE to the soil. Toxicological assessments, including Phytotoxkit FTM, Microtox® bioassay, and Ostracodtoxkit®, demonstrated phytotoxicity, acute toxicity, and high mortality in living organisms (over 85% for Heterocypris Incongruens). An unusual concentration of contaminants in the MWL’s middle layers, linked to Poland’s economic changes during the 1980s and 1990s, suggests increased risks of pollutant migration, posing additional environmental and health threats. Moreover, the infiltration capability of microorganisms, including pathogens, into PE structures raises concerns about potential groundwater contamination through the landfill bottom. This research underscores the need for vigilant management and updated strategies to protect the environment and public health, particularly in older landfill sites.
Full article
(This article belongs to the Special Issue Residues of Organic Pollutants in Environmental Samples, 2nd Edition)
►▼
Show Figures
Graphical abstract
Open AccessArticle
Production of Agarose-Hydroxyapatite Composites via Supercritical Gel Drying, for Bone Tissue Engineering
by
Alessandra Zanotti, Lucia Baldino, Stefano Cardea and Ernesto Reverchon
Molecules 2024, 29(11), 2498; https://doi.org/10.3390/molecules29112498 (registering DOI) - 25 May 2024
Abstract
Bone tissue engineering (BTE) is the most promising strategy to repair bones injuries and defects. It relies on the utilization of a temporary support to host the cells and promote nutrient exchange (i.e., the scaffold). Supercritical CO2 assisted drying can preserve scaffold
[...] Read more.
Bone tissue engineering (BTE) is the most promising strategy to repair bones injuries and defects. It relies on the utilization of a temporary support to host the cells and promote nutrient exchange (i.e., the scaffold). Supercritical CO2 assisted drying can preserve scaffold nanostructure, crucial for cell attachment and proliferation. In this work, agarose aerogels, loaded with hydroxyapatite were produced in view of BTE applications. Different combinations of agarose concentration and hydroxyapatite loadings were tested. FESEM and EDX analyses showed that scaffold structure suffered from partial closure when increasing filler concentration; hydroxyapatite distribution was homogenous, and Young’s modulus improved. Looking at BTE applications, the optimal combination of agarose and hydroxyapatite resulted to be 1% w/w and 10% w/v, respectively. Mechanical properties showed that the produced composites could be eligible as starting scaffold for BTE, with a Young’s Modulus larger than 100 kPa for every blend.
Full article
(This article belongs to the Special Issue Processing of Materials by Supercritical Fluids—Part II)
►▼
Show Figures
Figure 1
Open AccessArticle
Design, Synthesis, and Photophysical Properties of 5-Aminobiphenyl Substituted [1,2,4]Triazolo[4,3-c]- and [1,2,4]Triazolo[1,5-c]quinazolines
by
Tatyana N. Moshkina, Alexandra E. Kopotilova, Marya A. Ivan’kina, Ekaterina S. Starnovskaya, Denis A. Gazizov, Emiliya V. Nosova, Dmitry S. Kopchuk, Oleg S. El’tsov, Pavel A. Slepukhin and Valery N. Charushin
Molecules 2024, 29(11), 2497; https://doi.org/10.3390/molecules29112497 - 24 May 2024
Abstract
Two series of novel [1,2,4]triazolo[4,3-c]- and [1,2,4]triazolo[1,5-c]quinazoline fluorophores with 4′-amino[1,1′]-biphenyl residue at position 5 have been prepared via Pd-catalyzed cross-coupling Suzuki–Miyaura reactions. The treatment of 2-(4-bromophenyl)-4-hydrazinoquinazoline
[...] Read more.
Two series of novel [1,2,4]triazolo[4,3-c]- and [1,2,4]triazolo[1,5-c]quinazoline fluorophores with 4′-amino[1,1′]-biphenyl residue at position 5 have been prepared via Pd-catalyzed cross-coupling Suzuki–Miyaura reactions. The treatment of 2-(4-bromophenyl)-4-hydrazinoquinazoline with orthoesters in solvent-free conditions or in absolute ethanol leads to the formation of [4,3-c]-annulated triazoloquinazolines, whereas [1,5-c] isomers are formed in acidic media as a result of Dimroth rearrangement. A 1D-NMR and 2D-NMR spectroscopy, as well as a single-crystal X-ray diffraction analysis, unambiguously confirmed the annelation type and determined the molecular structure of p-bromophenyl intermediates and target products. Photophysical properties of the target compounds were investigated in two solvents and in the solid state and compared with those of related 3-aryl-substituted [1,2,4]triazolo[4,3-c]quinazolines. The exclusion of the aryl fragment from the triazole ring has been revealed to improve fluorescence quantum yield in solution. Most of the synthesized structures show moderate to high quantum yields in solution. Additionally, the effect of solvent polarity on the absorption and emission spectra of fluorophores has been studied, and considerable fluorosolvatochromism has been stated. Moreover, electrochemical investigation and DFT calculations have been performed; their results are consistent with the experimental observation.
Full article
(This article belongs to the Special Issue Synthesis and Properties of Heterocyclic Compounds: Recent Advances)
Journal Menu
► ▼ Journal Menu-
- Molecules Home
- Aims & Scope
- Editorial Board
- Reviewer Board
- Topical Advisory Panel
- Instructions for Authors
- Special Issues
- Topics
- Sections & Collections
- Article Processing Charge
- Indexing & Archiving
- Editor’s Choice Articles
- Most Cited & Viewed
- Journal Statistics
- Journal History
- Journal Awards
- Society Collaborations
- Conferences
- Editorial Office
Journal Browser
► ▼ Journal Browser-
arrow_forward_ios
Forthcoming issue
arrow_forward_ios Current issue - Vol. 29 (2024)
- Vol. 28 (2023)
- Vol. 27 (2022)
- Vol. 26 (2021)
- Vol. 25 (2020)
- Vol. 24 (2019)
- Vol. 23 (2018)
- Vol. 22 (2017)
- Vol. 21 (2016)
- Vol. 20 (2015)
- Vol. 19 (2014)
- Vol. 18 (2013)
- Vol. 17 (2012)
- Vol. 16 (2011)
- Vol. 15 (2010)
- Vol. 14 (2009)
- Vol. 13 (2008)
- Vol. 12 (2007)
- Vol. 11 (2006)
- Vol. 10 (2005)
- Vol. 9 (2004)
- Vol. 8 (2003)
- Vol. 7 (2002)
- Vol. 6 (2001)
- Vol. 5 (2000)
- Vol. 4 (1999)
- Vol. 3 (1998)
- Vol. 2 (1997)
- Volumes not published by MDPI
Highly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Beverages, Fermentation, Foods, Molecules, Separations
Advances in Analysis of Flavors and Fragrances: Chemistry, Properties and Applications in Food Quality Improvement
Topic Editors: Ana Leahu, Marìa Soledad Prats Moya, Cristina GhineaDeadline: 31 May 2024
Topic in
BioChem, Biomedicines, Biomolecules, IJMS, Metabolites, Molecules
Natural Products in Prevention and Therapy of Metabolic Syndrome
Topic Editors: Jianbo Wan, Ligen LinDeadline: 30 June 2024
Topic in
Molecules, Separations, Sustainability, Water, Minerals
Analysis and Separations of Trace Elements in the Environment
Topic Editors: Gene Hall, Begoña GonzálezDeadline: 31 July 2024
Topic in
Analytica, Molecules, Nanomaterials, Polymers, Separations
Nanomaterials in Green Analytical Chemistry
Topic Editors: George Zachariadis, Rosa Peñalver, Natalia ManousiDeadline: 15 August 2024
Conferences
Special Issues
Special Issue in
Molecules
Plant Secondary Metabolites with Health Effects: Discovery and Engineering
Guest Editors: Giuseppe Dionisio, Vittorio CalabreseDeadline: 31 May 2024
Special Issue in
Molecules
Electrochemical Sensors and Cells for Environmental Applications
Guest Editors: Naoufel Haddour, Yamina Mounia AzriDeadline: 16 June 2024
Special Issue in
Molecules
Nanomaterials for Electrocatalytic Applications
Guest Editor: Paolo BertoncelloDeadline: 30 June 2024
Special Issue in
Molecules
Recent Advances in Food Analysis
Guest Editors: Jesus Marin Saez, Rosalia Lopez Ruiz, Francisco Javier ArrebolaDeadline: 15 July 2024
Topical Collections
Topical Collection in
Molecules
Ultrasound- and Microwave-Assisted Extraction of Bioactive Compounds
Collection Editors: Stela Jokić, Jelena Vladić
Topical Collection in
Molecules
Novel Approache of Anticancer Therapy
Collection Editor: Isabelle Mus-Veteau