Molecules

13 pages, 5709 KiB

Open AccessArticle

DFT Surface Infers Ten-Vertex Cationic Carboranes from the Corresponding Neutral closo Ten-Vertex Family: The Computed Background Confirming Their Experimental Availability

by Michael L. McKee, Jan Vrána, Josef Holub, Jindřich Fanfrlík and Drahomír Hnyk

Molecules 2023, 28(8), 3645; https://doi.org/10.3390/molecules28083645 - 21 Apr 2023

Viewed by 1343

Abstract

Modern computational protocols based on the density functional theory (DFT) infer that polyhedral closo ten-vertex carboranes are key starting stationary states in obtaining ten-vertex cationic carboranes. The rearrangement of the bicapped square polyhedra into decaborane-like shapes with open hexagons in boat conformations is [...] Read more.

Modern computational protocols based on the density functional theory (DFT) infer that polyhedral closo ten-vertex carboranes are key starting stationary states in obtaining ten-vertex cationic carboranes. The rearrangement of the bicapped square polyhedra into decaborane-like shapes with open hexagons in boat conformations is caused by attacks of N-heterocyclic carbenes (NHCs) on the closo motifs. Single-point computations on the stationary points found during computational examinations of the reaction pathways have clearly shown that taking the “experimental” NHCs into account requires the use of dispersion correction. Further examination has revealed that for the purposes of the description of reaction pathways in their entirety, i.e., together with all transition states and intermediates, a simplified model of NHCs is sufficient. Many of such transition states resemble in their shapes those that dictate Z-rearrangement among various isomers of closo ten-vertex carboranes. Computational results are in very good agreement with the experimental findings obtained earlier. Full article

(This article belongs to the Special Issue New Developments in Boron Chemistry: From Oxidoborates to Hydrido(hetero)borane Derivatives – in Celebration of Professor John D. Kennedy’s 80th Birthday)

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13 pages, 1986 KiB

Open AccessArticle

Studies Relevant to the Functional Model of Mo-Cu CODH: In Situ Reactions of Cu(I)-L Complexes with Mo(VI) and Synthesis of Stable Structurally Characterized Heterotetranuclear Mo^VI₂Cu^I₂ Complex

by Umesh I. Kaluarachchige Don, Ahmad S. Almaat, Cassandra L. Ward and Stanislav Groysman

Molecules 2023, 28(8), 3644; https://doi.org/10.3390/molecules28083644 - 21 Apr 2023

Cited by 2 | Viewed by 2375

Abstract

In this study, we report the synthesis, characterization, and reactions of Cu(I) complexes of the general form Cu(L)(LigH₂) (LigH₂ = xanthene-based heterodinucleating ligand (E)-3-(((5-(bis(pyridin-2-ylmethyl)amino)-2,7-di-tert-butyl-9,9-dimethyl-9H-xanthen-4-yl)imino)methyl)benzene-1,2-diol); L = PMe₃, PPh₃, CN(2,6-Me₂C₆H₃)). New [...] Read more.

In this study, we report the synthesis, characterization, and reactions of Cu(I) complexes of the general form Cu(L)(LigH₂) (LigH₂ = xanthene-based heterodinucleating ligand (E)-3-(((5-(bis(pyridin-2-ylmethyl)amino)-2,7-di-tert-butyl-9,9-dimethyl-9H-xanthen-4-yl)imino)methyl)benzene-1,2-diol); L = PMe₃, PPh₃, CN(2,6-Me₂C₆H₃)). New complexes [Cu(PMe₃)(LigH₂)] and [CuCN(2,6-Me₂C₆H₃)(LigH₂)] were synthesized by treating [Cu(LigH₂)](PF₆) with trimethylphosphine and 2,6-dimethylphenyl isocyanide, respectively. These complexes were characterized by multinuclear NMR spectroscopy, IR spectroscopy, high-resolution mass spectrometry (HRMS), and X-ray crystallography. In contrast, attempted reactions of [Cu(LigH₂)](PF₆) with cyanide or styrene failed to produce isolable crystalline products. Next, the reactivity of these and previously synthesized Cu(I) phosphine and isocyanide complexes with molybdate was interrogated. IR (for isocyanide) and ³¹P NMR (for PPh₃/PMe₃) spectroscopy demonstrates the lack of oxidation reactivity. We also describe herein the first example of a structurally characterized multinuclear complex combining both Mo(VI) and Cu(I) metal ions within the same system. The heterobimetallic tetranuclear complex [Cu₂Mo₂O₄(μ₂-O)(Lig)₂]·HOSiPh₃ was obtained by the reaction of the silylated Mo(VI) precursor (Et₄N)(MoO₃(OSiPh₃)) with LigH₂, followed by the addition of [Cu(NCMe)₄](PF₆). This complex was characterized by NMR spectroscopy, high-resolution mass spectrometry, and X-ray crystallography. Full article

(This article belongs to the Special Issue Molybdenum and Tungsten Enzymes—State of the Art in Research)

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12 pages, 490 KiB

Open AccessArticle

Trametes hirsuta as an Attractive Biocatalyst for the Preparative Scale Biotransformation of Isosafrole into Piperonal

by Dawid Hernik, Ewa Szczepańska, Elisabetta Brenna, Katarzyna Patejuk, Teresa Olejniczak, Tomasz Strzała and Filip Boratyński

Molecules 2023, 28(8), 3643; https://doi.org/10.3390/molecules28083643 - 21 Apr 2023

Cited by 2 | Viewed by 1650

Abstract

Piperonal is a compound of key industrial importance due to its attractive olfactory and biological properties. It has been shown that among the fifty-six various fungal strains tested, the ability to cleave the toxic isosafrole into piperonal through alkene cleavage is mainly found [...] Read more.

Piperonal is a compound of key industrial importance due to its attractive olfactory and biological properties. It has been shown that among the fifty-six various fungal strains tested, the ability to cleave the toxic isosafrole into piperonal through alkene cleavage is mainly found in strains of the genus Trametes. Further studies involving strains isolated directly from different environments (decaying wood, fungal fruiting bodies, and healthy plant tissues) allowed the selection of two Trametes strains, T. hirsuta Th2_2 and T. hirsuta d28, as the most effective biocatalysts for the oxidation of isosafrole. The preparative scale of biotransformation with these strains provided 124 mg (conv. 82%, isolated yield 62%) and 101 mg (conv. 69%, isolated yield 50.5%) of piperonal, respectively. Due to the toxic impact of isosafrole on cells, preparative scale processes with Trametes strains have not yet been successfully performed and described in the literature. Full article

(This article belongs to the Special Issue Bioelements and Bioactive Metabolites of Natural Origin—Health-Promoting Applications)

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25 pages, 3395 KiB

Open AccessArticle

Potentiating Biosynthesis of Alkaloids and Polyphenolic Substances in Catharanthus roseus Plant Using ĸ-Carrageenan

by Hossam S. El-Beltagi, Salwa M. El-Sayed, Ahmed. N. Abdelhamid, Karim. M. Hassan, Walaa. A. Elshalakany, Mona Ibrahim Nossier, Nadiyah M. Alabdallah, Nadi Awad Al-Harbi, Salem Mesfir Al-Qahtani, Doaa Bahaa Eldin Darwish, Zahid Khorshid Abbas and Hemmat A. Ibrahim

Molecules 2023, 28(8), 3642; https://doi.org/10.3390/molecules28083642 - 21 Apr 2023

Cited by 7 | Viewed by 2332

Abstract

Catharanthus roseus is a medicinal plant that produces indole alkaloids, which are utilized in anticancer therapy. Vinblastine and vincristine, two commercially important antineoplastic alkaloids, are mostly found in the leaves of Catharanthus roseus. ĸ-carrageenan has been proven as plant growth promoting substance [...] Read more.

Catharanthus roseus is a medicinal plant that produces indole alkaloids, which are utilized in anticancer therapy. Vinblastine and vincristine, two commercially important antineoplastic alkaloids, are mostly found in the leaves of Catharanthus roseus. ĸ-carrageenan has been proven as plant growth promoting substance for a number of medicinal and agricultural plants. Considering the importance of ĸ-carrageenan as a promoter of plant growth and phytochemical constituents, especially alkaloids production in Catharanthus roseus, an experiment was carried out to explore the effect of ĸ-carrageenan on the plant growth, phytochemicals content, pigments content, and production of antitumor alkaloids in Catharanthus roseus after planting. Foliar application of ĸ-carrageenan (at 0, 400, 600 and 800 ppm) significantly improved the performance of Catharanthus roseus. Phytochemical analysis involved determining the amount of total phenolics (TP), flavonoids (F), free amino acids (FAA), alkaloids (TAC) and pigments contents by spectrophotometer, minerals by ICP, amino acids, phenolic compounds and alkaloids (Vincamine, Catharanthine, Vincracine (Vincristine), and vinblastine) analysis uses HPLC. The results indicated that all examined ĸ-carrageenan treatments led to a significant (p ≤ 0.05) increase in growth parameters compared to the untreated plants. Phytochemical examination indicates that the spray of ĸ-carrageenan at 800 mg L⁻¹ increased the yield of alkaloids (Vincamine, Catharanthine and Vincracine (Vincristine)) by 41.85 μg/g DW, total phenolic compounds by 3948.6 μg gallic/g FW, the content of flavonoids 951.3 μg quercetin /g FW and carotenoids content 32.97 mg/g FW as compared to the control. An amount of 400 ppm ĸ-carrageenan treatment gave the best contents of FAA, Chl a, Chl b and anthocyanin. The element content of K, Ca, Cu, Zn and Se increased by treatments. Amino acids constituents and phenolics compounds contents were altered by ĸ-carrageenan. Full article

(This article belongs to the Special Issue Identification of Bioactive Compounds from Natural Products)

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16 pages, 1498 KiB

Open AccessReview

The Buzz on Insecticides: A Review of Uses, Molecular Structures, Targets, Adverse Effects, and Alternatives

by Maria F. Araújo, Elisabete M. S. Castanheira and Sérgio F. Sousa

Molecules 2023, 28(8), 3641; https://doi.org/10.3390/molecules28083641 - 21 Apr 2023

Cited by 36 | Viewed by 10313

Abstract

Insecticides play a critical role in controlling the spread of insect-borne diseases and preserving crop health. These chemical substances are specifically formulated to kill or manage insect populations. Over the years, various types of insecticides have been developed, including organophosphates, carbamates, pyrethroids, and [...] Read more.

Insecticides play a critical role in controlling the spread of insect-borne diseases and preserving crop health. These chemical substances are specifically formulated to kill or manage insect populations. Over the years, various types of insecticides have been developed, including organophosphates, carbamates, pyrethroids, and neonicotinoids, each with unique modes of action, physiological targets, and efficacy. Despite the advantages that insecticides offer, it is imperative to recognize the potential consequences on non-target species, the environment, and human health. It is therefore crucial to follow recommended label instructions and employ integrated pest management practices for the judicious use of insecticides. This review article provides an in-depth examination of the various types of insecticides, including their modes of action, physiological targets, environmental and human health impacts, and alternatives. The aim is to furnish a comprehensive overview of insecticides and to emphasize the significance of responsible and sustainable utilization. Full article

(This article belongs to the Special Issue Novel Targets in Pest Control: Molecular Characterization, Structural and Biochemical Properties, Physiological Functions, and Evolution)

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17 pages, 4609 KiB

Open AccessArticle

Preparation of Multifunctional Surfactants Derived from Sodium Dodecylbenzene Sulfonate and Their Use in Oil-Field Chemistry

by Yongfei Li, Quanzheng Bai, Qiang Li, Hai Huang, Weijun Ni, Qian Wang, Xin Xin, Bin Zhao and Gang Chen

Molecules 2023, 28(8), 3640; https://doi.org/10.3390/molecules28083640 - 21 Apr 2023

Cited by 16 | Viewed by 2547

Abstract

Four products were obtained from sodium dodecylbenzene sulfonate (SDBS) and formaldehyde (40% solution) using a simple reaction. The products were characterized by TGA, IR, UV and MS to confirm the major chemicals in each sample. The new products could reduce the interfacial tension [...] Read more.

Four products were obtained from sodium dodecylbenzene sulfonate (SDBS) and formaldehyde (40% solution) using a simple reaction. The products were characterized by TGA, IR, UV and MS to confirm the major chemicals in each sample. The new products could reduce the interfacial tension between oil and water in the experimental temperature range further compared to SDBS. The emulsion ability was also enhanced by SDBS-1 to SDBS-4. The oil-displacement efficiencies of SDBS-1 to SDBS-4 were obviously higher than that of SDBS, and the oil-displacement efficiency of SDBS-2 was the best, with an efficiency of 25%. The experimental results all indicate that these products have an excellent ability to reduce oil–water interfacial tension and that they can be used in the oil and petrochemical industry for oil production and have certain practical uses. Full article

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30 pages, 2203 KiB

Open AccessFeature PaperReview

Biological Potential of Carnivorous Plants from Nepenthales

by Magdalena Wójciak, Marcin Feldo, Piotr Stolarczyk and Bartosz J. Płachno

Molecules 2023, 28(8), 3639; https://doi.org/10.3390/molecules28083639 - 21 Apr 2023

Cited by 4 | Viewed by 4906

Abstract

Since Charles Darwin and his book carnivorous plants have aroused interest and heated debate. In addition, there is growing interest in this group of plants as a source of secondary metabolites and in the application of their biological activity. The aim of this [...] Read more.

Since Charles Darwin and his book carnivorous plants have aroused interest and heated debate. In addition, there is growing interest in this group of plants as a source of secondary metabolites and in the application of their biological activity. The aim of this study was to trace the recent literature in search of the application of extracts obtained from families Droseraceae, Nepenthaceae, and Drosophyllaceae to show their biological potential. The data collected in the review clearly indicate that the studied Nepenthales species have great biological potential in terms of antibacterial, antifungal, antioxidant, anti-inflammatory, and anticancer use. We proposed that further investigations should include: (i) bioactivity-guided investigations of crude plant extract to connect a particular type of action with a specific compound or a group of metabolites; (ii) a search for new bioactive properties of carnivorous plants; (iii) establishment of molecular mechanisms associated with specific activity. Furthermore, further research should be extended to include less explored species, i.e., Drosophyllum lusitanicum and especially Aldrovanda vesiculosa. Full article

(This article belongs to the Special Issue Medicinal Value of Natural Bioactive Compounds and Plant Extracts)

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17 pages, 1311 KiB

Open AccessArticle

Rapid Assembly of Pyrrole-Ligated 1,3,4-Oxadiazoles and Excellent Antibacterial Activity of Iodophenol Substituents

by Hyein Kim, Lina Gu, Huisu Yeo, Umji Choi, Chang-Ro Lee, Haiyang Yu and Sangho Koo

Molecules 2023, 28(8), 3638; https://doi.org/10.3390/molecules28083638 - 21 Apr 2023

Cited by 2 | Viewed by 1991

Abstract

Pyrrole-ligated 1,3,4-oxadiazole is a very important pharmacophore which exhibits broad therapeutic effects such as anti-tuberculosis, anti-epileptic, anti-HIV, anti-cancer, anti-inflammatory, antioxidant, and antibacterial activities. A one-pot Maillard reaction between D-Ribose and an L-amino methyl ester in DMSO with oxalic acid at 2.5 atm and [...] Read more.

Pyrrole-ligated 1,3,4-oxadiazole is a very important pharmacophore which exhibits broad therapeutic effects such as anti-tuberculosis, anti-epileptic, anti-HIV, anti-cancer, anti-inflammatory, antioxidant, and antibacterial activities. A one-pot Maillard reaction between D-Ribose and an L-amino methyl ester in DMSO with oxalic acid at 2.5 atm and 80 °C expeditiously produced pyrrole-2-carbaldehyde platform chemicals in reasonable yields, which were utilized for the synthesis of pyrrole-ligated 1,3,4-oxadiazoles. Benzohydrazide reacted with the formyl group of the pyrrole platforms to provide the corresponding imine intermediates, which underwent I₂-mediated oxidative cyclization to the pyrrole-ligated 1,3,4-oxadiazole skeleton. The structure and activity relationship (SAR) of the target compounds with varying alkyl or aryl substituents of the amino acids and electron-withdrawing or electron-donating substituents on the phenyl ring of benzohydrazide were evaluated for antibacterial activity against Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii as representative Gram(–) and Gram(+) bacteria. Branched alkyl groups from the amino acid showed better antibacterial activities. Absolutely superior activities were observed for 5f-1 with an iodophenol substituent against A. baumannii (MIC < 2 μg/mL), a bacterial pathogen that displays a high resistance to commonly used antibiotics. Full article

(This article belongs to the Special Issue Recent Developments in the Synthesis and Functionalization of Nitrogen Heterocycles)

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12 pages, 5009 KiB

Open AccessArticle

A Novel Non-Metallic Photocatalyst: Phosphorus-Doped Sulfur Quantum Dots

by Ziyi Liu, Chuanfu Shan, Guiyu Wei, Jianfeng Wen, Li Jiang, Guanghui Hu, Zhijie Fang, Tao Tang and Ming Li

Molecules 2023, 28(8), 3637; https://doi.org/10.3390/molecules28083637 - 21 Apr 2023

Cited by 3 | Viewed by 2100

Abstract

In this paper, a novel phosphorus-doped sulfur quantum dots (P-SQDs) material was prepared using a simple hydrothermal method. P-SQDs have a narrow particle size distribution as well as an excellent electron transfer rate and optical properties. Compositing P-SQDs with graphitic carbon nitride (g-C [...] Read more.

In this paper, a novel phosphorus-doped sulfur quantum dots (P-SQDs) material was prepared using a simple hydrothermal method. P-SQDs have a narrow particle size distribution as well as an excellent electron transfer rate and optical properties. Compositing P-SQDs with graphitic carbon nitride (g-C₃N₄) can be used for photocatalytic degradation of organic dyes under visible light. More active sites, a narrower band gap, and stronger photocurrent are obtained after introducing P-SQDs into g-C₃N₄, thus promoting its photocatalytic efficiency by as much as 3.9 times. The excellent photocatalytic activity and reusability of P-SQDs/g-C₃N₄ are prospective signs of its photocatalytic application under visible light. Full article

(This article belongs to the Special Issue Wastewater Treatment: Functional Materials and Advanced Technology)

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20 pages, 3662 KiB

Open AccessReview

Senkyunolide I: A Review of Its Phytochemistry, Pharmacology, Pharmacokinetics, and Drug-Likeness

by Yan Huang, Yan Wu, Hongxiang Yin, Leilei Du and Chu Chen

Molecules 2023, 28(8), 3636; https://doi.org/10.3390/molecules28083636 - 21 Apr 2023

Cited by 8 | Viewed by 2403

Abstract

Senkyunolide I (SI) is a natural phthalide that has drawn increasing interest for its potential as a cardio-cerebral vascular drug candidate. In this paper, the botanical sources, phytochemical characteristics, chemical and biological transformations, pharmacological and pharmacokinetic properties, and drug-likeness of SI are reviewed [...] Read more.

Senkyunolide I (SI) is a natural phthalide that has drawn increasing interest for its potential as a cardio-cerebral vascular drug candidate. In this paper, the botanical sources, phytochemical characteristics, chemical and biological transformations, pharmacological and pharmacokinetic properties, and drug-likeness of SI are reviewed through a comprehensive literature survey, in order to provide support for its further research and applications. In general, SI is mainly distributed in Umbelliferae plants, and it is relatively stable to heat, acid, and oxygen, with good blood–brain barrier (BBB) permeability. Substantial studies have established reliable methods for the isolation, purification, and content determination of SI. Its pharmacological effects include analgesic, anti-inflammatory, antioxidant, anti-thrombotic, anti-tumor effects, alleviating ischemia–reperfusion injury, etc. Pharmacokinetic parameters indicate that its metabolic pathway is mainly phase Ⅱ metabolism, and it is rapidly absorbed in vivo and widely distributed in the kidneys, liver, and lungs. Full article

(This article belongs to the Special Issue Chemical, Nutraceutical Composition and Potential Bio Pharmacological Properties of the Medicinal Plants)

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15 pages, 2818 KiB

Open AccessArticle

Rapid Detection of Cd²⁺ Ions in the Aqueous Medium Using a Highly Sensitive and Selective Turn-On Fluorescent Chemosensor

by Maria Sadia, Jehangir Khan, Rizwan Khan, Abdul Waheed Kamran, Muhammad Zahoor, Riaz Ullah, Ahmed Bari and Essam A. Ali

Molecules 2023, 28(8), 3635; https://doi.org/10.3390/molecules28083635 - 21 Apr 2023

Cited by 4 | Viewed by 1853

Abstract

Herein, a novel optical chemosensor, (CM1 = 2, 6-di((E)-benzylidene)-4-methylcyclohexan-1-one), was designed/synthesized and characterized by ¹H-NMR and FT-IR spectroscopy. The experimental observations indicated that CM1 is an efficient and selective chemosensor towards Cd²⁺, even in the presence of other metal [...] Read more.

Herein, a novel optical chemosensor, (CM1 = 2, 6-di((E)-benzylidene)-4-methylcyclohexan-1-one), was designed/synthesized and characterized by ¹H-NMR and FT-IR spectroscopy. The experimental observations indicated that CM1 is an efficient and selective chemosensor towards Cd²⁺, even in the presence of other metal ions, such as Mn²⁺, Cu²⁺, Co^2+, Ce³⁺, K⁺, Hg²⁺,^, and Zn²⁺ in the aqueous medium. The newly synthesized chemosensor, CM1, showed a significant change in the fluorescence emission spectrum upon coordination with Cd²⁺. The formation of the Cd²⁺ complex with CM1 was confirmed from the fluorometric response. The 1:2 combination of Cd²⁺ with CM1 was found optimum for the desired optical properties, which was confirmed through fluorescent titration, Job’s plot, and DFT calculation. Moreover, CM1 showed high sensitivity towards Cd²⁺ with a very low detection limit (19.25 nM). Additionally, the CM1 was recovered and recycled by the addition of EDTA solution that combines with Cd²⁺ ion and, hence, frees up the chemosensor. Full article

(This article belongs to the Section Analytical Chemistry)

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20 pages, 8496 KiB

Open AccessArticle

Dihydropyrimidone Derivatives as Thymidine Phosphorylase Inhibitors: Inhibition Kinetics, Cytotoxicity, and Molecular Docking

by Tian-Meng Cui, Muhammad Altaf, Abdu Aldarhami, Abdulrahman S. Bazaid, Nizar H. Saeedi, Almohanad A. Alkayyal, Fahad M. Alshabrmi, Farman Ali, Mohammed Aladhadh, Muhammad Yasir Khan, Ahad Amer Alsaiari and Yue-Rong Ma

Molecules 2023, 28(8), 3634; https://doi.org/10.3390/molecules28083634 - 21 Apr 2023

Cited by 3 | Viewed by 2199

Abstract

Overexpression of the thymidine phosphorylase (TP) enzyme induces angiogenesis, which eventually leads to metastasis and tumor growth. The crucial role of TP in cancer development makes it an important target for anticancer drug discovery. Currently, there is only one US-FDA-approved drug, i.e., Lonsurf, [...] Read more.

Overexpression of the thymidine phosphorylase (TP) enzyme induces angiogenesis, which eventually leads to metastasis and tumor growth. The crucial role of TP in cancer development makes it an important target for anticancer drug discovery. Currently, there is only one US-FDA-approved drug, i.e., Lonsurf, a combination of trifluridine and tipiracil, for the treatment of metastatic colorectal cancer. Unfortunately, numerous adverse effects are associated with its use, such as myelosuppression, anemia, and neutropenia. Since the last few decades, the discovery of new, safe, and effective TP inhibitory agents has been rigorously pursued. In the present study, we evaluated a series of previously synthesized dihydropyrimidone derivatives 1–40 for their TP inhibitory potential. Compounds 1, 12, and 33 showed a good activity with IC₅₀ = 314.0 ± 0.90, 303.5 ± 0.40, and 322.6 ± 1.60 µM, respectively. The results of mechanistic studies revealed that compounds 1, 12, and 33 were the non-competitive inhibitors. These compounds were also evaluated for cytotoxicity against 3T3 (mouse fibroblast) cells and were found to be non-cytotoxic. Finally, the molecular docking suggested the plausible mechanism of non-competitive inhibition of TP. The current study thus identifies some dihydropyrimidone derivatives as potential inhibitors of TP, which can be further optimized as leads for cancer treatment. Full article

(This article belongs to the Special Issue Five and Six-Membered Heterocyclic Compounds and Their Therapeutic Potential)

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22 pages, 2623 KiB

Open AccessReview

Microbial Synthesis of Heme b: Biosynthetic Pathways, Current Strategies, Detection, and Future Prospects

by Qiuyu Yang, Juntao Zhao, Yangyang Zheng, Tao Chen and Zhiwen Wang

Molecules 2023, 28(8), 3633; https://doi.org/10.3390/molecules28083633 - 21 Apr 2023

Cited by 5 | Viewed by 3601

Abstract

Heme b, which is characterized by a ferrous ion and a porphyrin macrocycle, acts as a prosthetic group for many enzymes and contributes to various physiological processes. Consequently, it has wide applications in medicine, food, chemical production, and other burgeoning fields. Due [...] Read more.

Heme b, which is characterized by a ferrous ion and a porphyrin macrocycle, acts as a prosthetic group for many enzymes and contributes to various physiological processes. Consequently, it has wide applications in medicine, food, chemical production, and other burgeoning fields. Due to the shortcomings of chemical syntheses and bio-extraction techniques, alternative biotechnological methods have drawn increasing attention. In this review, we provide the first systematic summary of the progress in the microbial synthesis of heme b. Three different pathways are described in detail, and the metabolic engineering strategies for the biosynthesis of heme b via the protoporphyrin-dependent and coproporphyrin-dependent pathways are highlighted. The UV spectrophotometric detection of heme b is gradually being replaced by newly developed detection methods, such as HPLC and biosensors, and for the first time, this review summarizes the methods used in recent years. Finally, we discuss the future prospects, with an emphasis on the potential strategies for improving the biosynthesis of heme b and understanding the regulatory mechanisms for building efficient microbial cell factories. Full article

(This article belongs to the Special Issue Microbial Synthesis of Polymers and Polymer Precursors)

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16 pages, 1306 KiB

Open AccessArticle

Multidimensional Chromatographic Fingerprinting Combined with Chemometrics for the Identification of Regulated Plants in Suspicious Plant Food Supplements

by Surbhi Ranjan, Erwin Adams and Eric Deconinck

Molecules 2023, 28(8), 3632; https://doi.org/10.3390/molecules28083632 - 21 Apr 2023

Viewed by 1556

Abstract

The popularity of plant food supplements has seen explosive growth all over the world, making them susceptible to adulteration and fraud. This necessitates a screening approach for the detection of regulated plants in plant food supplements, which are usually composed of complex plant [...] Read more.

The popularity of plant food supplements has seen explosive growth all over the world, making them susceptible to adulteration and fraud. This necessitates a screening approach for the detection of regulated plants in plant food supplements, which are usually composed of complex plant mixtures, thus making the approach not so straightforward. This paper aims to tackle this problem by developing a multidimensional chromatographic fingerprinting method aided by chemometrics. To render more specificity to the chromatogram, a multidimensional fingerprint (absorbance × wavelength × retention time) was considered. This was achieved by selecting several wavelengths through a correlation analysis. The data were recorded using ultra-high-performance liquid chromatography (UHPLC) coupled with diode array detection (DAD). Chemometric modelling was performed by partial least squares–discriminant analysis (PLS-DA) through (a) binary modelling and (b) multiclass modelling. The correct classification rates (ccr%) by cross-validation, modelling, and external test set validation were satisfactory for both approaches, but upon further comparison, binary models were preferred. As a proof of concept, the models were applied to twelve samples for the detection of four regulated plants. Overall, it was revealed that the combination of multidimensional fingerprinting data with chemometrics was feasible for the identification of regulated plants in complex botanical matrices. Full article

(This article belongs to the Special Issue Development of Chemometrics: Now and Future)

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15 pages, 4936 KiB

Open AccessArticle

Design and Synthesis of a Novel ICT Bichromophoric pH Sensing System Based on 1,8-Naphthalimide Fluorophores as a Two-Input Logic Gate and Its Antibacterial Evaluation

by Alaa R. Sakr, Nikolai I. Georgiev and Vladimir B. Bojinov

Molecules 2023, 28(8), 3631; https://doi.org/10.3390/molecules28083631 - 21 Apr 2023

Cited by 4 | Viewed by 1871

Abstract

The synthesis, sensor activity, and logic behavior of a novel 4-iminoamido-1,8-naphthalimide bichromophoric system based on a “fluorophore-receptor” architecture with ICT chemosensing properties is reported. The synthesized compound showed good colorimetric and fluorescence signaling properties as a function of pH and proved [...] Read more.

The synthesis, sensor activity, and logic behavior of a novel 4-iminoamido-1,8-naphthalimide bichromophoric system based on a “fluorophore-receptor” architecture with ICT chemosensing properties is reported. The synthesized compound showed good colorimetric and fluorescence signaling properties as a function of pH and proved itself as a promising probe for the rapid detection of pH in an aqueous solution and base vapors in a solid state. The novel dyad is able to work as a two-input logic gate with chemical inputs H⁺ (Input 1) and HO⁻ (Input 2) executing INHIBIT logic gate. The synthesized bichromophoric system and the corresponding intermediates demonstrated good antibacterial activity toward Gram (+) and Gram (−) bacteria when compared with the Gentamycin standard. Full article

(This article belongs to the Special Issue Exclusive Feature Papers in Physical Chemistry)

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14 pages, 3601 KiB

Open AccessArticle

Salvianolic Acid A Improves Rat Kidney Injury by Regulating MAPKs and TGF-β1/Smads Signaling Pathways

by Hai-Yang Diao, Wei Zhu, Jie Liu, Sheng Yin, Jin-Hui Wang and Chun-Li Li

Molecules 2023, 28(8), 3630; https://doi.org/10.3390/molecules28083630 - 21 Apr 2023

Cited by 8 | Viewed by 2037

Abstract

Salvianolic acid A (SAA) is one of the major components in Salvia miltiorrhiza Bge., with various pharmacological activities, and is likely to be a promising agent for the treatment of kidney diseases. The purpose of this study was to explore the protective [...] Read more.

Salvianolic acid A (SAA) is one of the major components in Salvia miltiorrhiza Bge., with various pharmacological activities, and is likely to be a promising agent for the treatment of kidney diseases. The purpose of this study was to explore the protective effect and mechanisms of SAA on kidney disease. In this study, the improvement effects of SAA (10, 20, 40 mg/kg, i.g.) on kidney injury rats were investigated by detecting the levels of KIM-1, NGAL in serum and UP in the urine of AKI model rats established with gentamicin, as well as the levels of SCr and UREA in serum and IL-6, IL-12, MDA and T-SOD in the kidneys of CKD model rats established with 5/6 nephrectomy. HE and Masson staining were used to observe the histopathological changes in the kidney. Network pharmacology and Western blotting were used to explore the mechanism of SAA in improving kidney injury. The results showed that SAA improved kidney function in kidney injury rats by reducing the kidney index and pathological injury by HE and Masson staining, reducing the levels of KIM-1, NGAL and UP in AKI rats and UREA, SCr and UP in CKD rats, as well as exerting anti-inflammatory and anti-oxidative stress effects by inhibiting the release of IL-6 and IL-12, reducing MDA and increasing T-SOD. Western blotting results showed that SAA significantly reduced the phosphorylation levels of ERK1/2, p38, JNK and smad2/3, and the expression of TLR-4 and smad7. In conclusion, SAA plays a significant role in improving kidney injury in rats and the mechanism may be achieved by regulating the MAPKs and TGF-β1/smads signaling pathways. Full article

(This article belongs to the Special Issue Study on Chemical Constituents and Pharmacological Action of Natural Medicines)

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12 pages, 2634 KiB

Open AccessArticle

Experimental and Simulation Studies on Hematite Interaction with Na-Metasilicate Pentahydrate

by Gonzalo R. Quezada, Norman Toro, R. S. Krishna, Subhabrata Mishra, Pedro Robles, Ivan Salazar, Enoque Mathe and Ricardo I. Jeldres

Molecules 2023, 28(8), 3629; https://doi.org/10.3390/molecules28083629 - 21 Apr 2023

Cited by 1 | Viewed by 1754

Abstract

Iron ore is a fundamental pillar in construction globally, however, its process is highly polluting and deposits are becoming less concentrated, making reusing or reprocessing its sources a sustainable solution to the current industry. A rheological analysis was performed to understand the effect [...] Read more.

Iron ore is a fundamental pillar in construction globally, however, its process is highly polluting and deposits are becoming less concentrated, making reusing or reprocessing its sources a sustainable solution to the current industry. A rheological analysis was performed to understand the effect of sodium metasilicate on the flow curves of concentrated pulps. The study was carried out in an Anton Paar MCR 102 rheometer, showing that, in a wide range of dosages, the reagent can reduce the yield stress of the slurries, which would result in lower energy costs for transporting the pulps by pumping. To understand the behavior observed experimentally, computational simulation has been used by means of quantum calculations to represent the metasilicate molecule and the molecular dynamics to study the adsorption of metasilicate on the hematite surface. It has been possible to obtain that the adsorption is stable on the surface of hematite, where increasing the concentration of metasilicate increases its adsorption on the surface. The adsorption could be modeled by the Slips model where there is a delay in adsorption at low concentrations and then a saturated value is reached. It was found that metasilicate requires the presence of sodium ions to be adsorbed on the surface by means of a cation bridge-type interaction. It is also possible to identify that it is absorbed by means of hydrogen bridges, but to a lesser extent than the cation bridge. Finally, it is observed that the presence of metasilicate adsorbed on the surface modifies the net surface charge, increasing it and, thus, generating the effect of dispersion of hematite particles which experimentally is observed as a decrease in rheology. Full article

(This article belongs to the Special Issue Computational and Theoretical Chemistry for Material Research)

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19 pages, 10590 KiB

Open AccessFeature PaperArticle

Identification of Protein Quality Markers in Toad Venom from Bufo gargarizans

by Meiyun Yang, Weiwei Huan, Guobing Zhang, Jie Li, Fengyan Xia, Rabia Durrani, Wei Zhao, Jidong Lu, Xinmeng Peng and Fei Gao

Molecules 2023, 28(8), 3628; https://doi.org/10.3390/molecules28083628 - 21 Apr 2023

Cited by 4 | Viewed by 2256

Abstract

Toad venom is a traditional Chinese medicine with high medicinal value. The existing quality evaluation standards of toad venom have obvious limitations because of the lack of research on proteins. Thus, it is necessary to screen suitable quality markers and establish appropriate quality [...] Read more.

Toad venom is a traditional Chinese medicine with high medicinal value. The existing quality evaluation standards of toad venom have obvious limitations because of the lack of research on proteins. Thus, it is necessary to screen suitable quality markers and establish appropriate quality evaluation methods for toad venom proteins to guarantee their safety and efficacy in clinical applications. SDS-PAGE, HPLC, and cytotoxicity assays were used to analyze differences in protein components of toad venom from different areas. Functional proteins were screened as potential quality markers by proteomic and bioinformatic analyses. The protein components and small molecular components of toad venom were not correlated in content. Additionally, the protein component had strong cytotoxicity. Proteomics analysis showed that 13 antimicrobial proteins, four anti-inflammatory and analgesic proteins, and 20 antitumor proteins were differentially expressed extracellular proteins. A candidate list of functional proteins was coded as potential quality markers. Moreover, Lysozyme C-1, which has antimicrobial activity, and Neuropeptide B (NPB), which has anti-inflammatory and analgesic activity, were identified as potential quality markers for toad venom proteins. Quality markers can be used as the basis of quality studies of toad venom proteins and help to construct and improve safe, scientific, and comprehensive quality evaluation methods. Full article

(This article belongs to the Special Issue Mass Spectrometry in Biomarkers Discovery)

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12 pages, 3498 KiB

Open AccessArticle

Morphology and Properties of Polylactic Acid Composites with Butenediol Vinyl Alcohol Copolymer Formed by Melt Blending

by Jian Xing, Rongrong Wang, Shaoyang Sun, Ying Shen, Botao Liang and Zhenzhen Xu

Molecules 2023, 28(8), 3627; https://doi.org/10.3390/molecules28083627 - 21 Apr 2023

Cited by 2 | Viewed by 2106

Abstract

Due to its poor toughness and hydrophilicity, the application of polylactic acid (PLA) in the field of absorbent sanitary materials is restricted. A butenediol vinyl alcohol copolymer (BVOH) was used to improve PLA via melt blending. The morphology, molecular structure, crystallization, thermal stability, [...] Read more.

Due to its poor toughness and hydrophilicity, the application of polylactic acid (PLA) in the field of absorbent sanitary materials is restricted. A butenediol vinyl alcohol copolymer (BVOH) was used to improve PLA via melt blending. The morphology, molecular structure, crystallization, thermal stability, tensile property, and hydrophilicity of PLA/BVOH composites with different mass ratios were investigated. The results show that the PLA/BVOH composites possessed a two-phase structure with good interfacial adhesion. The BVOH could effectively blend into PLA without a chemical reaction. The addition of the BVOH promoted the crystallization of PLA, improved the perfection of the crystalline region, and increased the glass transition temperature and melting temperature of PLA in the heating process. Moreover, the thermal stability of PLA was markedly improved by adding the BVOH. The addition of the BVOH also had a significant effect on the tensile property of the PLA/BVOH composites. When the content of the BVOH was 5 wt.%, the elongation at the break of the PLA/BVOH composites could reach 9.06% (increased by 76.3%). In addition, the hydrophilicity of PLA was also significantly improved, and the water contact angles decreased with the increase in the BVOH content and time. When the content of the BVOH was 10 wt.%, the water contact angle could reach 37.3° at 60 s, suggesting good hydrophilicity. Full article

(This article belongs to the Section Macromolecular Chemistry)

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12 pages, 3034 KiB

Open AccessArticle

Study of the Properties of CdS:Al (R = [Al³⁺]/[Cd²⁺] = 0.30, 0.40, 0.50) Thin Films Grown by the CBD Method in an Ammonia-Free System

by Raju Prasanna-Kumari, Daniela Herrera-Molina, Arturo Fernández-Pérez, Jesús E. Diosa and Edgar Mosquera-Vargas

Molecules 2023, 28(8), 3626; https://doi.org/10.3390/molecules28083626 - 21 Apr 2023

Cited by 3 | Viewed by 2342

Abstract

CdS:Al thin films were fabricated on a glass substrate using the CBD method. The effect of aluminum incorporation on the structural, morphological, vibrational, and optical properties of CdS thin layers was investigated by X-ray diffraction (XRD), Raman spectroscopy (RS), atomic force microscopy (AFM), [...] Read more.

CdS:Al thin films were fabricated on a glass substrate using the CBD method. The effect of aluminum incorporation on the structural, morphological, vibrational, and optical properties of CdS thin layers was investigated by X-ray diffraction (XRD), Raman spectroscopy (RS), atomic force microscopy (AFM), scanning electron microscopy (SEM), and UV-visible (UV-vis) and photoluminescence (PL) spectroscopies. XRD analysis of deposited thin films confirmed a hexagonal structure with a preferred (002) orientation in all samples. The crystallite size and surface morphology of the films are modified with aluminum content. Raman spectra exhibit fundamental longitudinal optical (LO) vibrational modes and their overtones. Optical properties were studied for each thin film. Here, it was observed that the optical properties of thin films are affected by the incorporation of aluminum into the CdS structure. Full article

(This article belongs to the Special Issue 2D Nanomaterials and Composites for Energy and Environmental Sustainability)

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24 pages, 6428 KiB

Open AccessArticle

Designing Electron-Deficient Diketone Unit Based Non-Fused Ring Acceptors with Amplified Optoelectronic Features for Highly Efficient Organic Solar Cells: A DFT Study

by Muhammad Usman Khan, Faiza Shafiq, Sanaa S. Al Abbad, Junaid Yaqoob, Riaz Hussain, Zainab H. A. Alsunaidi, Ghulam Mustafa and Shabbir Hussain

Molecules 2023, 28(8), 3625; https://doi.org/10.3390/molecules28083625 - 21 Apr 2023

Cited by 17 | Viewed by 2232

Abstract

Organic solar cells (OSCs) made of electron-acceptor and electron-donor materials have significantly developed in the last decade, demonstrating their enormous potential in cutting-edge optoelectronic applications. Consequently, we designed seven novel non-fused ring electron acceptors (NFREAs) (BTIC-U1 to BTIC-U7) using synthesized electron-deficient diketone units [...] Read more.

Organic solar cells (OSCs) made of electron-acceptor and electron-donor materials have significantly developed in the last decade, demonstrating their enormous potential in cutting-edge optoelectronic applications. Consequently, we designed seven novel non-fused ring electron acceptors (NFREAs) (BTIC-U1 to BTIC-U7) using synthesized electron-deficient diketone units and reported end-capped acceptors, a viable route for augmented optoelectronic properties. The DFT and TDDFT approaches were used to measure the power conversion efficiency (PCE), open circuit voltage (Voc), reorganization energies (λ_h, λ_e), fill factor (FF), light harvesting efficiency (LHE) and to evaluate the potential usage of proposed compounds in solar cell applications. The findings confirmed that the photovoltaic, photophysical, and electronic properties of the designed molecules BTIC-U1 to BTIC-U7 are superior to those of reference BTIC-R. The TDM analysis demonstrates a smooth flow of charge from the core to the acceptor groups. Charge transfer analysis of the BTIC-U1:PTB7-Th blend revealed orbital superposition and successful charge transfer from HOMO (PTB7-Th) to LUMO (BTIC-U1). The BTIC-U5 and BTIC-U7 outperformed the reference BTIC-R and other developed molecules in terms of PCE (23.29% and 21.18%), FF (0.901 and 0.894), normalized Voc (48.674 and 44.597), and Voc (1.261 eV and 1.155 eV). The proposed compounds enclose high electron and hole transfer mobilities, making them the ideal candidate for use with PTB7-Th film. As a result, future SM-OSC design should prioritize using these constructed molecules, which exhibit excellent optoelectronic properties, as superior scaffolds. Full article

(This article belongs to the Special Issue Recent Advancements in Density Functional Theory (DFT) and beyond for Computational Chemistry)

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19 pages, 659 KiB

Open AccessReview

Perhexiline: Old Drug, New Tricks? A Summary of Its Anti-Cancer Effects

by Bimala Dhakal, Yoko Tomita, Paul Drew, Timothy Price, Guy Maddern, Eric Smith and Kevin Fenix

Molecules 2023, 28(8), 3624; https://doi.org/10.3390/molecules28083624 - 21 Apr 2023

Cited by 7 | Viewed by 2824

Abstract

Cancer metabolic plasticity, including changes in fatty acid metabolism utilisation, is now widely appreciated as a key driver for cancer cell growth, survival and malignancy. Hence, cancer metabolic pathways have been the focus of much recent drug development. Perhexiline is a prophylactic antianginal [...] Read more.

Cancer metabolic plasticity, including changes in fatty acid metabolism utilisation, is now widely appreciated as a key driver for cancer cell growth, survival and malignancy. Hence, cancer metabolic pathways have been the focus of much recent drug development. Perhexiline is a prophylactic antianginal drug known to act by inhibiting carnitine palmitoyltransferase 1 (CPT1) and 2 (CPT2), mitochondrial enzymes critical for fatty acid metabolism. In this review, we discuss the growing evidence that perhexiline has potent anti-cancer properties when tested as a monotherapy or in combination with traditional chemotherapeutics. We review the CPT1/2 dependent and independent mechanisms of its anti-cancer activities. Finally, we speculate on the clinical feasibility and utility of repurposing perhexiline as an anti-cancer agent, its limitations including known side effects and its potential added benefit of limiting cardiotoxicity induced by other chemotherapeutics. Full article

(This article belongs to the Collection Efficient Pharmaceutical and Chemical Approaches for Anticancer Therapy: Design, Preliminary Evaluations, and Further Developments)

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13 pages, 4804 KiB

Open AccessArticle

Phytoestrogens as Biomarkers of Plant Raw Materials Used for Fish Feed Production

by Dionysios T. Pavlopoulos, Eleni D. Myrtsi, Paschalitsa Tryfinopoulou, Vasilios Iliopoulos, Sofia D. Koulocheri and Serkos A. Haroutounian

Molecules 2023, 28(8), 3623; https://doi.org/10.3390/molecules28083623 - 21 Apr 2023

Cited by 1 | Viewed by 2328

Abstract

The intensive use of plant materials as a sustainable alternative for fish feed production, combined with their phytochemical content, which affects the growth and production characteristics of farmed fishes, necessitates their monitoring for the presence of raw materials of plant origin. This study [...] Read more.

The intensive use of plant materials as a sustainable alternative for fish feed production, combined with their phytochemical content, which affects the growth and production characteristics of farmed fishes, necessitates their monitoring for the presence of raw materials of plant origin. This study reported herein concerns the development, validation and application of a workflow using high-performance liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) for the quantification of 67 natural phytoestrogens in plant-derived raw materials that were used to produce fish feeds. Specifically, we verified the presence of 8 phytoestrogens in rapeseed meal samples, 20 in soybean meal samples, 12 in sunflower meal samples and only 1 in wheat meal samples in quantities enabling their efficient incorporation into clusters. Among the various constituents, the soybean phytoestrogens daidzein, genistein, daidzin, glycitin, apigenin, calycosin and coumestrol, as well as the sunflower neochlorogenic, caffeic and chlorogenic phenolic acids, displayed the highest correlations with their origin descriptions. A hierarchical cluster analysis of the studied samples, based on their phytoestrogen contents, led to the efficient clustering of raw materials. The accuracy and efficiency of this clustering were tested through the incorporation of additional samples of soybean meal, wheat meal and maize meal, which verified the utilization of the phytoestrogen content as a valuable biomarker for the discrimination of raw materials used for fish feed production. Full article

(This article belongs to the Section Natural Products Chemistry)

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22 pages, 7443 KiB

Open AccessReview

Synthesis and Peroxide Activation Mechanism of Bimetallic MOF for Water Contaminant Degradation: A Review

by Mengke Fan, Jingwei Yan, Quantao Cui, Run Shang, Qiting Zuo, Lin Gong and Wei Zhang

Molecules 2023, 28(8), 3622; https://doi.org/10.3390/molecules28083622 - 21 Apr 2023

Cited by 21 | Viewed by 4296

Abstract

Metal–organic framework (MOF) materials possess a large specific surface area, high porosity, and atomically dispersed metal active sites, which confer excellent catalytic performance as peroxide (peroxodisulfate (PDS), peroxomonosulfate (PMS), and hydrogen peroxide (H₂O₂)) activation catalysts. However, the limited electron [...] Read more.

Metal–organic framework (MOF) materials possess a large specific surface area, high porosity, and atomically dispersed metal active sites, which confer excellent catalytic performance as peroxide (peroxodisulfate (PDS), peroxomonosulfate (PMS), and hydrogen peroxide (H₂O₂)) activation catalysts. However, the limited electron transfer characteristics and chemical stability of traditional monometallic MOFs restrict their catalytic performance and large-scale application in advanced oxidation reactions. Furthermore, the single-metal active site and uniform charge density distribution of monometallic MOFs result in a fixed activation reaction path of peroxide in the Fenton-like reaction process. To address these limitations, bimetallic MOFs have been developed to improve catalytic activity, stability, and reaction controllability in peroxide activation reactions. Compared with monometallic MOFs, bimetallic MOFs enhance the active site of the material, promote internal electron transfer, and even alter the activation path through the synergistic effect of bimetals. In this review, we systematically summarize the preparation methods of bimetallic MOFs and the mechanism of activating different peroxide systems. Moreover, we discuss the reaction factors that affect the process of peroxide activation. This report aims to expand the understanding of bimetallic MOF synthesis and their catalytic mechanisms in advanced oxidation processes. Full article

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15 pages, 2392 KiB

Open AccessArticle

Isomers of the Tomato Glycoalkaloids α-Tomatine and Dehydrotomatine: Relationship to Health Benefits

by Nobuyuki Kozukue, Dong-Seok Kim, Suk-Hyun Choi, Masashi Mizuno and Mendel Friedman

Molecules 2023, 28(8), 3621; https://doi.org/10.3390/molecules28083621 - 21 Apr 2023

Cited by 4 | Viewed by 2712

Abstract

High-performance liquid chromatography (HPLC) analysis of three commercial tomatine samples and another isolated from green tomatoes revealed the presence of two small peaks in addition to those associated with the glycoalkaloids dehydrotomatine and α-tomatine. The present study investigated the possible structures of the [...] Read more.

High-performance liquid chromatography (HPLC) analysis of three commercial tomatine samples and another isolated from green tomatoes revealed the presence of two small peaks in addition to those associated with the glycoalkaloids dehydrotomatine and α-tomatine. The present study investigated the possible structures of the compounds associated with the two small peaks using HPLC–mass spectrophotometric (MS) methods. Although the two peaks elute much earlier on chromatographic columns than the elution times of the known tomato glycoalkaloids dehydrotomatine and α-tomatine, isolation of the two compounds by preparative chromatography and subsequent analysis by MS shows the two compounds have identical molecular weights, tetrasaccharide side chains, and MS and MS/MS fragmentation patterns to dehydrotomatine and α-tomatine. We suggest the two isolated compounds are isomeric forms of dehydrotomatine and α-tomatine. The analytical data indicate that widely used commercial tomatine preparations and those extracted from green tomatoes and tomato leaves consist of a mixture of α-tomatine, dehydrotomatine, an α-tomatine isomer, and a dehydrotomatine isomer in an approximate ratio of 81:15:4:1, respectively. The significance of the reported health benefits of tomatine and tomatidine is mentioned. Full article

(This article belongs to the Special Issue Application of Liquid Chromatography in Food and Natural Products Extracts Analysis)

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14 pages, 2493 KiB

Open AccessArticle

A Novel Strategy of Combined Pulsed Electro-Oxidation and Electrolysis for Degradation of Sulfadiazine

by Dong Ma, Bo Zhang and Xiaomin Hu

Molecules 2023, 28(8), 3620; https://doi.org/10.3390/molecules28083620 - 21 Apr 2023

Cited by 2 | Viewed by 1493

Abstract

A combination of the peroxymonosulfate (PMS) electro-activation process and the electro-oxidation process driven by a pulsed electric field (PEF) was used to degrade sulfadiazine (SND) wastewater. Mass transfer is the limiting step of electrochemical processes. The PEF could enhance mass transfer efficiency by [...] Read more.

A combination of the peroxymonosulfate (PMS) electro-activation process and the electro-oxidation process driven by a pulsed electric field (PEF) was used to degrade sulfadiazine (SND) wastewater. Mass transfer is the limiting step of electrochemical processes. The PEF could enhance mass transfer efficiency by reducing the polarization effect and increasing the instantaneous limiting current compared with the constant electric field (CEF), which could benefit the electro-generation of active radicals. The degradation rate of SND after 2 h was 73.08%. The experiments investigated the effects of operating parameters of pulsed power supply, PMS dosage, pH value and electrode inter distance on the degradation rate of SND. The predicted response value of single-factor performance experiments was obtained as 72.26% after 2 h, which was basically consistent with the experimental value. According to the quenching experiments and EPR tests, both SO₄^•− and •OH were present in the electrochemical processes. The generation of active species were significantly greater in the PEF system than that in the CEF system. Moreover, four kinds of intermediate products were detected during the degradation by LC-MS. This paper presents a new aspect for electrochemical degradation of sulfonamide antibiotics. Full article

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13 pages, 2878 KiB

Open AccessArticle

Suppressing Kaposi’s Sarcoma-Associated Herpesvirus Lytic Gene Expression and Replication by RNase P Ribozyme

by Yujun Liu, Yuan-Chuan Chen, Bin Yan and Fenyong Liu

Molecules 2023, 28(8), 3619; https://doi.org/10.3390/molecules28083619 - 21 Apr 2023

Cited by 3 | Viewed by 1499

Abstract

Kaposi’s sarcoma, an AIDS-defining illness, is caused by Kaposi’s sarcoma-associated herpesvirus (KSHV), an oncogenic virus. In this study, we engineered ribozymes derived from ribonuclease P (RNase P) catalytic RNA with targeting against the mRNA encoding KSHV immediate early replication and transcription activator (RTA), [...] Read more.

Kaposi’s sarcoma, an AIDS-defining illness, is caused by Kaposi’s sarcoma-associated herpesvirus (KSHV), an oncogenic virus. In this study, we engineered ribozymes derived from ribonuclease P (RNase P) catalytic RNA with targeting against the mRNA encoding KSHV immediate early replication and transcription activator (RTA), which is vital for KSHV gene expression. The functional ribozyme F-RTA efficiently sliced the RTA mRNA sequence in vitro. In cells, KSHV production was suppressed with ribozyme F-RTA expression by 250-fold, and RTA expression was suppressed by 92–94%. In contrast, expression of control ribozymes hardly affected RTA expression or viral production. Further studies revealed both overall KSHV early and late gene expression and viral growth decreased because of F-RTA-facilitated suppression of RTA expression. Our results indicate the first instance of RNase P ribozymes having potential for use in anti-KSHV therapy. Full article

(This article belongs to the Special Issue Progress and Perspective of Antiviral Agents)

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16 pages, 5366 KiB

Open AccessArticle

Solubility and Stability of Carotenoids in Ammonium- and Phosphonium-Based Ionic Liquids: Effect of Solvent Nature, Temperature and Water

by Wanting Cheng, Feng Xian, Zhanluo Zhou, Kun Hu and Jing Gao

Molecules 2023, 28(8), 3618; https://doi.org/10.3390/molecules28083618 - 21 Apr 2023

Cited by 5 | Viewed by 3012

Abstract

Ionic liquids (ILs) have arisen as alternatives to organic solvents and been used in natural pigment extraction in recent decades. However, the solubility and stability of carotenoids in phosphonium- and ammonium-based ILs are insufficiently explored. In this work, the physicochemical properties of the [...] Read more.

Ionic liquids (ILs) have arisen as alternatives to organic solvents and been used in natural pigment extraction in recent decades. However, the solubility and stability of carotenoids in phosphonium- and ammonium-based ILs are insufficiently explored. In this work, the physicochemical properties of the ILs, and the dissolution behavior and storage stability of three carotenoids (astaxanthin, β-carotene, and lutein) in the IL aqueous solution were investigated. The results showed that the solubility of the carotenoids in the acidic IL solution is higher than that in the alkaline IL solution, and the optimal pH is about 6. The solubility of astaxanthin (40 mg/100 g), β-carotene (105 mg/100 g), and lutein (5250 mg/100 g) was the highest in tributyloctylphosphonium chloride ([P₄₄₄₈]Cl) due to the van der Waals forces with [P₄₄₄₈]⁺ and hydrogen bonding with Cl⁻. A high temperature was beneficial to improve the solubility, but it can reduce the storage stability. Water has no significant effect on the carotenoid stability, but a high water content decreases the carotenoid solubility. A IL water content of 10–20%, an extraction temperature of 338.15 K, and a storage temperature of less than 298.15 K are beneficial for reducing the IL viscosity, improving carotenoid solubility, and maintaining good stability. Moreover, a linear correlation was found between the color parameters and carotenoid contents. This study provides some guidance for screening suitable solvents for carotenoid extraction and storage. Full article

(This article belongs to the Special Issue Greener Ionic Liquids)

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14 pages, 388 KiB

Open AccessArticle

Prediction of Proteins in Cerebrospinal Fluid and Application to Glioma Biomarker Identification

by Kai He, Yan Wang, Xuping Xie and Dan Shao

Molecules 2023, 28(8), 3617; https://doi.org/10.3390/molecules28083617 - 21 Apr 2023

Cited by 2 | Viewed by 1691

Abstract

Cerebrospinal fluid (CSF) proteins are very important because they can serve as biomarkers for central nervous system diseases. Although many CSF proteins have been identified with wet experiments, the identification of CSF proteins is still a challenge. In this paper, we propose a [...] Read more.

Cerebrospinal fluid (CSF) proteins are very important because they can serve as biomarkers for central nervous system diseases. Although many CSF proteins have been identified with wet experiments, the identification of CSF proteins is still a challenge. In this paper, we propose a novel method to predict proteins in CSF based on protein features. A two-stage feature-selection method is employed to remove irrelevant features and redundant features. The deep neural network and bagging method are used to construct the model for the prediction of CSF proteins. The experiment results on the independent testing dataset demonstrate that our method performs better than other methods in the prediction of CSF proteins. Furthermore, our method is also applied to the identification of glioma biomarkers. A differentially expressed gene analysis is performed on the glioma data. After combining the analysis results with the prediction results of our model, the biomarkers of glioma are identified successfully. Full article

(This article belongs to the Special Issue Mass Spectrometric Proteomics III)

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16 pages, 3614 KiB

Open AccessArticle

Optimization of Physical Refining Process of Camellia Oil for Reduction of 3-Monochloropropane-1,2-Diol (3-MCPD) Ester Formation Using Response Surface Methodology on a Laboratory Scale

by Liqun Zhang, Pinggu Wu, Xiaoling Xiang, Dajin Yang, Liyuan Wang and Zhengyan Hu

Molecules 2023, 28(8), 3616; https://doi.org/10.3390/molecules28083616 - 21 Apr 2023

Cited by 3 | Viewed by 1406

Abstract

Refined and deodorized camellia oil has been reported to contain a high amount of 3-monochloropropane-1,2-diol esters (3-MCPDE) due to the high-temperature deodorization step. To reduce 3-MCPDE in camellia oil, the physical refining process of camellia oil was simulated on a laboratory scale. Response [...] Read more.

Refined and deodorized camellia oil has been reported to contain a high amount of 3-monochloropropane-1,2-diol esters (3-MCPDE) due to the high-temperature deodorization step. To reduce 3-MCPDE in camellia oil, the physical refining process of camellia oil was simulated on a laboratory scale. Response surface methodology (RSM) was designed to modify and optimize the refining process with five processing parameters (water degumming dosage, degumming temperature, activated clay dosage, deodorization temperature and deodorization time). The optimized new refining approach achieved a 76.9% reduction in 3-MCPDE contents, in which the degumming moisture was 2.97%, the degumming temperature was 50.5 °C, the activated clay dosage was 2.69%, the deodorizing temperature was 230 °C, and the deodorizing time was 90 min. A significance test and analysis of variance results demonstrated that the deodorization temperature and deodorization time contributed significantly to the reduction of 3-MCPD ester. The joint interaction effects of activated clay dosage and deodorization temperature were significant for 3-MCPD ester formation. Full article

(This article belongs to the Section Food Chemistry)

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