Molecules

21 pages, 44865 KiB

Open AccessArticle

Systematic Qualitative and Quantitative Analyses of Wenxin Granule via Ultra-High Performance Liquid Chromatography Coupled with Ion Mobility Quadrupole Time-of-Flight Mass Spectrometry and Triple Quadrupole–Linear Ion Trap Mass Spectrometry

by Yueguang Mi, Wandi Hu, Weiwei Li, Shiyu Wan, Xiaoyan Xu, Meiyu Liu, Hongda Wang, Quanxi Mei, Qinhua Chen, Yang Yang, Boxue Chen, Meiting Jiang, Xue Li, Wenzhi Yang and Dean Guo

Molecules 2022, 27(11), 3647; https://doi.org/10.3390/molecules27113647 - 6 Jun 2022

Cited by 7 | Viewed by 3079

Abstract

Wenxin granule (WXG) is a popular traditional Chinese medicine (TCM) preparation for the treatment of arrhythmia disease. Potent analytical technologies are needed to elucidate its chemical composition and assess the quality differences among multibatch samples. In this work, both a multicomponent characterization and [...] Read more.

Wenxin granule (WXG) is a popular traditional Chinese medicine (TCM) preparation for the treatment of arrhythmia disease. Potent analytical technologies are needed to elucidate its chemical composition and assess the quality differences among multibatch samples. In this work, both a multicomponent characterization and quantitative assay of WXG were conducted using two liquid chromatography–mass spectrometry (LC-MS) approaches. An ultra-high performance liquid chromatography–ion mobility quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS) approach combined with intelligent peak annotation workflows was developed to characterize the multicomponents of WXG. A hybrid scan approach enabling alternative data-independent and data-dependent acquisitions was established. We characterized 205 components, including 92 ginsenosides, 53 steroidal saponins, 14 alkaloids, and 46 others. Moreover, an optimized scheduled multiple reaction monitoring (sMRM) method was elaborated, targeting 24 compounds of WXG via ultra-high performance liquid chromatography–triple quadrupole linear ion trap mass spectrometry (UHPLC/QTrap-MS), which was validated based on its selectivity, precision, stability, repeatability, linearity, sensitivity, recovery, and matrix effect. By applying this method to 27 batches of WXG samples, the content variations of multiple markers from Notoginseng Radix et Rhizoma (21) and Codonopsis Radix (3) were depicted. Conclusively, we achieved the comprehensive multicomponent characterization and holistic quality assessment of WXG by targeting the non-volatile components. Full article

(This article belongs to the Special Issue State-of-the-Art Analytical Technologies for Natural Products)

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13 pages, 2489 KiB

Open AccessArticle

Effects of pH and Ionic Salts on the Emulsifying and Rheological Properties of Acorn Protein Isolate

by Nasir Mehmood Khan, Muhammad Saeed, Farman Ali Khan, Shujaat Ahmad, Muhammad Asif Nawaz, Zia Ullah Khan, Muhammad Shafique, Mazen Almehmadi, Osama Abdulaziz and Abid Ullah

Molecules 2022, 27(11), 3646; https://doi.org/10.3390/molecules27113646 - 6 Jun 2022

Cited by 1 | Viewed by 2279

Abstract

This study was designed to evaluate the emulsifying and rheological properties of acorn protein isolate (API) in different pH mediums (pH 3, 7 and 9) and in the presence of ionic salts (1 M NaCl and 1 M CaCl₂). API shows [...] Read more.

This study was designed to evaluate the emulsifying and rheological properties of acorn protein isolate (API) in different pH mediums (pH 3, 7 and 9) and in the presence of ionic salts (1 M NaCl and 1 M CaCl₂). API shows higher solubility in distilled water at pH 7, while at the same pH, a decrease in solubility was observed for API in the presence of CaCl₂ (61.30%). A lower emulsifying activity index (EAI), lower stability index (ESI), larger droplet sizes and slight flocculation were observed for API in the presence of salts at different pHs. Importantly, CaCl₂ treated samples showed relevantly higher EAI (252.67 m²/g) and ESI (152.67 min) values at all pH as compared to NaCl (221.76 m²/g), (111.82 min), respectively. A significant increase in interfacial protein concentration (4.61 mg/m²) was observed for emulsion at pH 9 with CaCl₂, while the major fractions of API were observed in an interfacial layer after SDS-PAGE analysis. All of the emulsion shows shear thinning behavior (τ_c > 0 and n < 1), while the highest viscosity was observed for emulsion prepared with CaCl₂ at pH 3 (11.03 ± 1.62). In conclusion, API, in the presence of ionic salts at acidic, neutral and basic pH, can produce natural emulsions, which could be substitutes for synthetic surfactants for such formulations. Full article

(This article belongs to the Special Issue Molecular Characteristics and Functional Properties in Agri-Food)

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13 pages, 9798 KiB

Open AccessArticle

Comparison of Widely Targeted Metabolomics and Untargeted Metabolomics of Wild Ophiocordyceps sinensis

by Jinna Zhou, Donghai Hou, Weiqiu Zou, Jinhu Wang, Run Luo, Mu Wang and Hong Yu

Molecules 2022, 27(11), 3645; https://doi.org/10.3390/molecules27113645 - 6 Jun 2022

Cited by 24 | Viewed by 4752

Abstract

The authors of this paper conducted a comparative metabolomic analysis of Ophiocordyceps sinensis (OS), providing the metabolic profiles of the stroma (OSBSz) and sclerotia (OSBSh) of OS by widely targeted metabolomics and untargeted metabolomics. The results showed that 778 and 1449 metabolites were [...] Read more.

The authors of this paper conducted a comparative metabolomic analysis of Ophiocordyceps sinensis (OS), providing the metabolic profiles of the stroma (OSBSz) and sclerotia (OSBSh) of OS by widely targeted metabolomics and untargeted metabolomics. The results showed that 778 and 1449 metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. The metabolites in OSBSz and OSBSh are significantly differentiated; 71 and 96 differentially expressed metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. This suggests that these 71 metabolites (riboflavine, tripdiolide, bromocriptine, lumichrome, tetrahymanol, citrostadienol, etc.) and 96 metabolites (sancycline, vignatic acid B, pirbuterol, rubrophen, epalrestat, etc.) are potential biomarkers. 4-Hydroxybenzaldehyde, arginine, and lumichrome were common differentially expressed metabolites. Using the widely targeted metabolomics approach, the key pathways identified that are involved in creating the differentiation between OSBSz and OSBSh may be nicotinate and nicotinamide metabolism, thiamine metabolism, riboflavin metabolism, glycine, serine, and threonine metabolism, and arginine biosynthesis. The differentially expressed metabolites identified using the untargeted metabolomics approach were mainly involved in arginine biosynthesis, terpenoid backbone biosynthesis, porphyrin and chlorophyll metabolism, and cysteine and methionine metabolism. The purpose of this research was to provide support for the assessment of the differences between the stroma and sclerotia, to furnish a material basis for the evaluation of the physical effects of OS, and to provide a reference for the selection of detection methods for the metabolomics of OS. Full article

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3 pages, 164 KiB

Open AccessEditorial

Editorial to the Special Issue: “Synthesis of Organic Ligands and Their Metal Complexes in Medicinal Chemistry”

by Irena Kostova

Molecules 2022, 27(11), 3644; https://doi.org/10.3390/molecules27113644 - 6 Jun 2022

Cited by 2 | Viewed by 1764

Abstract

The field of medicinal (organic, bioinorganic, and coordination) chemistry as well as the interdisciplinary studies related to medicine is a rapidly developing area of study [...] Full article

(This article belongs to the Special Issue Synthesis of Organic Ligands and Their Metal Complexes in Medicinal Chemistry)

15 pages, 2683 KiB

Open AccessArticle

Structural Characterization and In-Vitro Antioxidant and Immunomodulatory Activities of Polysaccharide Fractions Isolated from Artemisia annua L.

by Lin Zhang, Narsimha Reddy, Cheang Soo Khoo and Sundar Rao Koyyalamudi

Molecules 2022, 27(11), 3643; https://doi.org/10.3390/molecules27113643 - 6 Jun 2022

Cited by 10 | Viewed by 2547

Abstract

Arimisia annua L. is an important anticancer herb used in traditional Chinese medicine. The molecular basis underpinning the anticancer activity is complex and not fully understood, but the herbal polysaccharides, broadly recognised as having immunomodulatory, antioxidant and anticancer activities, are potential key active [...] Read more.

Arimisia annua L. is an important anticancer herb used in traditional Chinese medicine. The molecular basis underpinning the anticancer activity is complex and not fully understood, but the herbal polysaccharides, broadly recognised as having immunomodulatory, antioxidant and anticancer activities, are potential key active agents. To examine the functions of polysaccharides from A. annua, their immunomodulatory and antioxidant potentials were evaluated, as well as their structural characterization. The water-soluble polysaccharides (AAPs) were fractionated using size-exclusion chromatography to obtain three dominant fractions, AAP-1, AAP-2 and AAP-3, having molecular masses centered around 1684, 455 and 5.8kDa, respectively. The antioxidant potentials of the isolated polysaccharides were evaluated by measuring radical scavenging activities against DPPH^● (2,2-diphenyl-1-picrylhydrazyl radical), ABTS^●+ (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid radical ion), and the OH^● (hydroxyl radical). AAP-1 displayed high antioxidant activities against these radicals, which were 68%, 73% and 78%, respectively. AAP-2 displayed lower scavenging activities than the other two fractions. Immunostimulatory activities of AAPs were measured using mouse macrophages. The three polysaccharide fractions displayed significant antioxidant activities and stimulated the production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). AAP-1 showed significant immunostimulatory activity (16-fold increase in the production of IL-6 compared to the control and 13-fold increase in the production of TNF-α) with low toxicity (>60% cell viability at 125 μg/mL concentration). Preliminary structural characterization of the AAPs was carried out using gas chromatography (GC) and FTIR techniques. The results indicate that AAP-1 and AAP-2 are pyranose-containing polysaccharides with β-linkages, and AAP-3 is a β-fructofuranoside. The results suggest that these polysaccharides are potential candidates for immunotherapy and cancer treatment. Full article

(This article belongs to the Special Issue Extraction, Separation and Identification of Compounds from Natural Sources)

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16 pages, 2116 KiB

Open AccessArticle

Synthesis and Luminescent Properties of s-Tetrazine Derivatives Conjugated with the 4H-1,2,4-Triazole Ring

by Anna Maj, Agnieszka Kudelko and Marcin Świątkowski

Molecules 2022, 27(11), 3642; https://doi.org/10.3390/molecules27113642 - 6 Jun 2022

Cited by 3 | Viewed by 2392

Abstract

New derivatives obtained by the combination of unique 1,2,4,5-tetrazine and 4H-1,2,4-triazole rings have great application potential in many fields. Therefore, two synthetic few-step methodologies, which make use of commercially available 4-cyanobenzoic acid (method A) and ethyl diazoacetate (method B), were applied [...] Read more.

New derivatives obtained by the combination of unique 1,2,4,5-tetrazine and 4H-1,2,4-triazole rings have great application potential in many fields. Therefore, two synthetic few-step methodologies, which make use of commercially available 4-cyanobenzoic acid (method A) and ethyl diazoacetate (method B), were applied to produce two groups of the aforementioned heterocyclic conjugates. In both cases, the target compounds were obtained in various combinations, by introducing electron-donating or electron-withdrawing substituents into the terminal rings, together with aromatic or aliphatic substituents on the triazole nitrogen atom. Synthesis of such designed systems made it possible to analyze the influence of individual elements of the structure on the reaction course, as well as the absorption and emission properties. The structure of all products was confirmed by conventional spectroscopic methods, and their luminescent properties were also determined. Full article

(This article belongs to the Special Issue Synthesis of Heteroaromatic Compounds)

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13 pages, 3060 KiB

Open AccessArticle

Effects of Poncirin, a Citrus Flavonoid and Its Aglycone, Isosakuranetin, on the Gut Microbial Diversity and Metabolomics in Mice

by Xuedan Cao, Xiao Guo, Xiugui Fang, Shuijiang Ru and Erhu Li

Molecules 2022, 27(11), 3641; https://doi.org/10.3390/molecules27113641 - 6 Jun 2022

Cited by 4 | Viewed by 3357

Abstract

Poncirin (PC) and its aglycone, isosakuranetin (IR), occur naturally in citrus fruits. This study aimed to explore the pathways behind the different health benefits of PC and IR by evaluating the effect of these two bioactive flavonoids on the gut microbial diversity and [...] Read more.

Poncirin (PC) and its aglycone, isosakuranetin (IR), occur naturally in citrus fruits. This study aimed to explore the pathways behind the different health benefits of PC and IR by evaluating the effect of these two bioactive flavonoids on the gut microbial diversity and metabolomics of mice. The 16S rRNA gene sequencing was used to analyze the alteration of gut microbiota in mice after PC and IR intervention. The metabolic impact of PC and IR in mice were studied using a metabolomics approach based on LC-MS analysis. Results showed that, after 7 days intervention, PC and IR multiplied the abundance of Parabacteroides in mice’s intestinal tracts by 1.2 and 1.0 times, respectively. PC increased the abundance of Bacteroides by 2.4 times. IR reduced the Allobaculum abundance by 1.0 time and increased Alloprevotella abundance by 1.5 times. When mice were given PC, their fecal acetic acid level increased by 1.8 times, while their isobutyric and isovaleric acid content increased by 1.2 and 1.3 times, respectively. Supplementation with IR had no significant effect on the content of short-chain fatty acids (SCFAs) in the feces of mice. The potential urine biomarkers of mice in the PC group were involved in the digestion and absorption of protein and carbohydrate, as well as the metabolism of amino acids, such as glycine, serine, threonine, tryptophan, D-arginine, D-ornithine, etc. IR mainly affected the amino acid metabolic pathways in mice, including taurine and hypotaurine metabolism, glutathione metabolism, histidine metabolism, D-glutamate metabolism, etc. This study provided valuable clues for future research on the health promoting mechanisms of PC and IR. Full article

(This article belongs to the Topic The Effect of Phytochemicals and Food Bioactive Compounds on the Metabolic Syndrome and Diabetes including Ethnopharmacological Aspects)

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25 pages, 8252 KiB

Open AccessArticle

Biocompatibility Assessment of Polylactic Acid (PLA) and Nanobioglass (n-BG) Nanocomposites for Biomedical Applications

by Jorge Iván Castro, Carlos Humberto Valencia Llano, Diego López Tenorio, Marcela Saavedra, Paula Zapata, Diana Paola Navia-Porras, Johannes Delgado-Ospina, Manuel N. Chaur, José Hermínsul Mina Hernández and Carlos David Grande-Tovar

Molecules 2022, 27(11), 3640; https://doi.org/10.3390/molecules27113640 - 6 Jun 2022

Cited by 5 | Viewed by 2744

Abstract

Scaffolds based on biopolymers and nanomaterials with appropriate mechanical properties and high biocompatibility are desirable in tissue engineering. Therefore, polylactic acid (PLA) nanocomposites were prepared with ceramic nanobioglass (PLA/n-BGs) at 5 and 10 wt.%. Bioglass nanoparticles (n-BGs) were prepared using a sol–gel methodology [...] Read more.

Scaffolds based on biopolymers and nanomaterials with appropriate mechanical properties and high biocompatibility are desirable in tissue engineering. Therefore, polylactic acid (PLA) nanocomposites were prepared with ceramic nanobioglass (PLA/n-BGs) at 5 and 10 wt.%. Bioglass nanoparticles (n-BGs) were prepared using a sol–gel methodology with a size of ca. 24.87 ± 6.26 nm. In addition, they showed the ability to inhibit bacteria such as Escherichia coli (ATCC 11775), Vibrio parahaemolyticus (ATCC 17802), Staphylococcus aureus subsp. aureus (ATCC 55804), and Bacillus cereus (ATCC 13061) at concentrations of 20 w/v%. The analysis of the nanocomposite microstructures exhibited a heterogeneous sponge-like morphology. The mechanical properties showed that the addition of 5 wt.% n-BG increased the elastic modulus of PLA by ca. 91.3% (from 1.49 ± 0.44 to 2.85 ± 0.99 MPa) and influenced the resorption capacity, as shown by histological analyses in biomodels. The incorporation of n-BGs decreased the PLA crystallinity (from 7.1% to 4.98%) and increased the glass transition temperature (T_g) from 53 °C to 63 °C. In addition, the n-BGs increased the thermal stability due to the nanoparticle’s intercalation between the polymeric chains and the reduction in their movement. The histological implantation of the nanocomposites and the cell viability with HeLa cells higher than 80% demonstrated their biocompatibility character with a greater resorption capacity than PLA. These results show the potential of PLA/n-BGs nanocomposites for biomedical applications, especially for long healing processes such as bone tissue repair and avoiding microbial contamination. Full article

(This article belongs to the Special Issue Antimicrobial and Antibacterial Films for Tissue Regeneration)

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16 pages, 1820 KiB

Open AccessArticle

Nanoemulsions of Jasminum humile L. and Jasminum grandiflorum L. Essential Oils: An Approach to Enhance Their Cytotoxic and Antiviral Effects

by Khaled Ahmed Mansour, Mona El-Neketi, Mohamed-Farid Lahloub and Ahmed Elbermawi

Molecules 2022, 27(11), 3639; https://doi.org/10.3390/molecules27113639 - 6 Jun 2022

Cited by 14 | Viewed by 2965

Abstract

Unprecedented nanoemulsion formulations (NE) of Jasminum humile and Jasminum grandiflorum essential oils (EO) were prepared, and examined for their cytotoxic and antiviral activities. NE characterization and stability examination tests were performed to ensure formula stability. The antiviral activity was determined against hepatitis A [...] Read more.

Unprecedented nanoemulsion formulations (NE) of Jasminum humile and Jasminum grandiflorum essential oils (EO) were prepared, and examined for their cytotoxic and antiviral activities. NE characterization and stability examination tests were performed to ensure formula stability. The antiviral activity was determined against hepatitis A (HAV) and herpes simplex type-1 (HSV-1) viruses using MTT assay, while the cytotoxic potential was determined against liver (HepG-2), breast (MCF-7), leukemia (THP-1) cancer cell lines and normal Vero cells. Statistical significance was determined in comparison with doxorubicin as cytotoxic and acyclovir as antiviral standard drugs. GC-MS analysis indicated twenty four compounds in the EO of J. humile and seventeen compounds in the EO of J. grandiflorum. Biological investigations of pure EOs revealed weak cytotoxic and antiviral effects. Nevertheless, their NE formulations exhibited high biological value as cytotoxic and antiviral agents. NE formulations also showed feasible selectivity index for the viral-infected and cancer cells (especially HepG-2) than normal Vero cells. Both nanoemulsions showed lower IC₅₀ than standard doxorubicin against HepG-2 (26.65 and 22.58 vs. 33.96 μg/mL) and MCF-7 (36.09 and 36.19 vs. 52.73 μg/mL), respectively. The study results showed the dramatic effect of nanoemulsion preparation on the biological activity of EOs and other liposoluble phytopharmaceuticals. Full article

(This article belongs to the Special Issue Natural Products That Might Change Society)

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22 pages, 1434 KiB

Open AccessArticle

Mass Defect Filtering-Oriented Identification of Resin Glycosides from Root of Convolvulus scammonia Based on Quadrupole-Orbitrap Mass Spectrometer

by Qiang Yin, Rahima Abdulla, Gulmira Kahar, Haji Akber Aisa, Chunting Li and Xuelei Xin

Molecules 2022, 27(11), 3638; https://doi.org/10.3390/molecules27113638 - 6 Jun 2022

Cited by 5 | Viewed by 2177

Abstract

This work aimed to develop and evaluate a post-acquisition data processing strategy, referred to as a mass defect filter (MDF), for rapid target the resin glycosides in root of Convolvulus scammonia by setting mass rang and mass defect range from high-resolution MS data. [...] Read more.

This work aimed to develop and evaluate a post-acquisition data processing strategy, referred to as a mass defect filter (MDF), for rapid target the resin glycosides in root of Convolvulus scammonia by setting mass rang and mass defect range from high-resolution MS data. The full-scan mass data were acquired by high-performance liquid chromatography coupled with Q Exactive Plus hybrid quadrupole-orbitrap mass spectrometer that featured high resolution, mass accuracy, and sensitivity. To screen resin glycosides, three parent filter m/z 871, m/z 853, and m/z 869 combined with diagnostic fragment ions (DFIs) approach were applied to remove the interference from complex herbal extract. The targeted components were characterized based on detailed fragment ions. Using this approach, 80 targeted components, including 22 glycosidic acids and 58 resin glycosides were tentatively identified. The present results suggested that the proposed MDF strategy would be adaptable to the analysis of complex system in relevant filed. Full article

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

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18 pages, 2155 KiB

Open AccessReview

The Fight against Infection and Pain: Devil’s Claw (Harpagophytum procumbens) a Rich Source of Anti-Inflammatory Activity: 2011–2022

by Nomagugu Gxaba and Madira Coutlyne Manganyi

Molecules 2022, 27(11), 3637; https://doi.org/10.3390/molecules27113637 - 6 Jun 2022

Cited by 13 | Viewed by 10633

Abstract

Harpagophytum procumbens subsp. procumbens (Burch.) DC. ex Meisn. (Sesame seed Family—Pedaliaceae) is a popular medicinal plant known as Devil’s claw. It is predominantly distributed widely over southern Africa. Its impressive reputation is embedded in its traditional uses as an indigenous herbal plant for [...] Read more.

Harpagophytum procumbens subsp. procumbens (Burch.) DC. ex Meisn. (Sesame seed Family—Pedaliaceae) is a popular medicinal plant known as Devil’s claw. It is predominantly distributed widely over southern Africa. Its impressive reputation is embedded in its traditional uses as an indigenous herbal plant for the treatment of menstrual problems, bitter tonic, inflammation febrifuge, syphilis or even loss of appetite. A number of bioactive compounds such as terpenoids, iridoid glycosides, glycosides, and acetylated phenolic compounds have been isolated. Harpagoside and harpagide, iridoid glycosides bioactive compounds have been reported in countless phytochemical studies as potential anti-inflammatory agents as well as pain relievers. In-depth studies have associated chronic inflammation with various diseases, such as Alzheimer’s disease, obesity, rheumatoid arthritis, type 2 diabetes, cancer, and cardiovascular and pulmonary diseases. In addition, 60% of chronic disorder fatalities are due to chronic inflammatory diseases worldwide. Inflammation and pain-related disorders have attracted significant attention as leading causes of global health challenges. Articles published from 2011 to the present were obtained and reviewed in-depth to determine valuable data findings as well as knowledge gaps. Various globally recognized scientific search engines/databases including Scopus, PubMed, Google Scholar, Web of Science, and ScienceDirect were utilized to collect information and deliver evidence. Based on the literature results, there was a dramatic decrease in the number of studies conducted on the anti-inflammatory and analgesic activity of Devil’s claw, thereby presenting a potential research gap. It is also evident that currently in vivo clinical studies are needed to validate the prior massive in vitro studies, therefore delivering an ideal anti-inflammatory and analgesic agent in the form of H. procumbens products. Full article

(This article belongs to the Special Issue Bioactive Compounds from Natural Resources)

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12 pages, 4077 KiB

Open AccessArticle

Formation of GeO₂ under Graphene on Ge(001)/Si(001) Substrates Using Water Vapor

by Ewa Dumiszewska, Paweł Ciepielewski, Piotr A. Caban, Iwona Jóźwik, Jaroslaw Gaca and Jacek M. Baranowski

Molecules 2022, 27(11), 3636; https://doi.org/10.3390/molecules27113636 - 6 Jun 2022

Viewed by 2023

Abstract

The problem of graphene protection of Ge surfaces against oxidation is investigated. Raman, X-Ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements of graphene epitaxially grown on Ge(001)/Si(001) substrates are presented. It is shown that the penetration of water [...] Read more.

The problem of graphene protection of Ge surfaces against oxidation is investigated. Raman, X-Ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements of graphene epitaxially grown on Ge(001)/Si(001) substrates are presented. It is shown that the penetration of water vapor through graphene defects on Gr/Ge(001)/Si(001) samples leads to the oxidation of germanium, forming GeO₂. The presence of trigonal GeO₂ under graphene was identified by Raman and XRD measurements. The oxidation of Ge leads to the formation of blisters under the graphene layer. It is suggested that oxidation of Ge is connected with the dissociation of water molecules and penetration of OH molecules or O to the Ge surface. It has also been found that the formation of blisters of GeO₂ leads to a dramatic increase in the intensity of the graphene Raman spectrum. The increase in the Raman signal intensity is most likely due to the screening of graphene by GeO₂ from the Ge(001) surface. Full article

(This article belongs to the Special Issue Graphene-Based Nanocomposites for Advanced Applications)

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4 pages, 198 KiB

Open AccessEditorial

New Advances in Short Peptides: Looking Forward

by Vasso Apostolopoulos, Joanna Bojarska, Tsun-Thai Chai, Jack Feehan, Krzysztof Kaczmarek, John M. Matsoukas, Octavio Paredes Lopez, Michele Saviano, Mariusz Skwarczynski, Jillian Smith-Carpenter, Mariano Venanzi, Wojciech M. Wolf, Piotr Zielenkiewicz and Zyta M. Ziora

Molecules 2022, 27(11), 3635; https://doi.org/10.3390/molecules27113635 - 6 Jun 2022

Cited by 9 | Viewed by 2624

Abstract

It is beyond doubt that short peptides hold significant promise in bio-medicine, as the most versatile molecules, both structurally and functionally [...] Full article

(This article belongs to the Special Issue Advances in Research of Short Peptides II)

33 pages, 13806 KiB

Open AccessReview

3D Graphene Foam by Chemical Vapor Deposition: Synthesis, Properties, and Energy-Related Applications

by Cristina Antonela Banciu, Florin Nastase, Anca-Ionela Istrate and Lucia Monica Veca

Molecules 2022, 27(11), 3634; https://doi.org/10.3390/molecules27113634 - 6 Jun 2022

Cited by 17 | Viewed by 4717

Abstract

In this review, we highlight recent advancements in 3D graphene foam synthesis by template-assisted chemical vapor deposition, as well as their potential energy storage and conversion applications. This method offers good control of the number of graphene layers and porosity, as well as [...] Read more.

In this review, we highlight recent advancements in 3D graphene foam synthesis by template-assisted chemical vapor deposition, as well as their potential energy storage and conversion applications. This method offers good control of the number of graphene layers and porosity, as well as continuous connection of the graphene sheets. The review covers all the substrate types, catalysts, and precursors used to synthesize 3D graphene by the CVD method, as well as their most viable energy-related applications. Full article

(This article belongs to the Special Issue Recent Progress of Graphene-Based Composites in Europe)

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15 pages, 2496 KiB

Open AccessArticle

Influence of Open Chain and Cyclic Structure of Peptidomimetics on Antibacterial Activity in E. coli Strains

by Parul Sahrawat, Paweł Kowalczyk, Dominik Koszelewski, Mateusz Szymczak, Karol Kramkowski, Aleksandra Wypych and Ryszard Ostaszewski

Molecules 2022, 27(11), 3633; https://doi.org/10.3390/molecules27113633 - 6 Jun 2022

Cited by 10 | Viewed by 2186

Abstract

An efficient method for the synthesis of functionalized peptidomimetics via multicomponent Ugi reaction has been developed. The application of trifluoroethanol (TFE) as a reaction medium provided desired products with good yields. Further, using the developed cyclisation reaction, the obtained peptidomimetics were transformed into [...] Read more.

An efficient method for the synthesis of functionalized peptidomimetics via multicomponent Ugi reaction has been developed. The application of trifluoroethanol (TFE) as a reaction medium provided desired products with good yields. Further, using the developed cyclisation reaction, the obtained peptidomimetics were transformed into the cyclic analogues (diketopiperazines, DKPs). The goal of the performed studies was to revised and compare whether the structure of the obtained structurally flexible acyclic peptidomimetics and their rigid cycling analogue DKPs affect antimicrobial activity. We studied the potential of synthesized peptidomimetics, both cyclic and acyclic, as antimicrobial drugs on model E. coli bacteria strains (k12, R2–R4). The biological assays reveal that DKPs hold more potential as antimicrobial drugs compared to open chain Ugi peptidomimetics. We believe that it can be due to the rigid cyclic structure of DKPs which promotes the membrane penetration in the cell of studied pathogens. The obtained data clearly indicate the high antibiotic potential of synthesized diketopiperazine derivatives over tested antibiotics. Full article

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9 pages, 2296 KiB

Open AccessArticle

One-Step, Low-Cost, Operator-Friendly, and Scalable Procedure to Synthetize Highly Pure N-(4-ethoxyphenyl)-retinamide in Quantitative Yield without Purification Work-Up

by Silvana Alfei and Guendalina Zuccari

Molecules 2022, 27(11), 3632; https://doi.org/10.3390/molecules27113632 - 6 Jun 2022

Viewed by 1986

Abstract

It is widely reported that N-(4-hydroxyphenyl)-retinamide or fenretinide (4-HPR), which is a synthetic amide of all-trans-retinoic acid (ATRA), inhibits in vitro several types of tumors, including cancer cell lines resistant to ATRA, at 1–10 µM concentrations. Additionally, studies in rats and mice [...] Read more.

It is widely reported that N-(4-hydroxyphenyl)-retinamide or fenretinide (4-HPR), which is a synthetic amide of all-trans-retinoic acid (ATRA), inhibits in vitro several types of tumors, including cancer cell lines resistant to ATRA, at 1–10 µM concentrations. Additionally, studies in rats and mice have confirmed the potent anticancer effects of 4-HPR, without evidencing hemolytic toxicity, thus demonstrating its suitability for the development of a new chemo-preventive agent. To this end, the accurate determination of 4-HPR levels in tissues is essential for its pre-clinical training, and for the correct determination of 4-HPR and its metabolites by chromatography, N-(4-ethoxyphenyl)-retinamide (4-EPR) has been suggested as an indispensable internal standard. Unfortunately, only a consultable old patent reports the synthesis of 4-EPR, starting from dangerous and high-cost reagents and using long and tedious purification procedures. To the best of our knowledge, no article existed so far describing the specific synthesis of 4-EPR. Only two vendors worldwide supply 4-ERP, and its characterization was incomplete. Here, a scalable, operator-friendly, and one-step procedure to synthetize highly pure 4-EPR without purification work-up and in quantitative yield is reported. Additionally, a complete characterization of 4-EPR using all possible analytical techniques has been provided. Full article

(This article belongs to the Special Issue Research of Organic Chemicals for Biological Applications)

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16 pages, 3947 KiB

Open AccessArticle

Antifungal Volatilomes Mediated Defense Mechanism against Fusarium oxysporum f. sp. lycopersici, the Incitant of Tomato Wilt

by Praveen Thangaraj, Akshaya Subbaih Balamurali, Krishnamoorthy Akkanna Subbiah, Nakkeeran Sevugapperumal, Thiribhuvanamala Gurudevan, Sivakumar Uthandi and Haripriya Shanmugam

Molecules 2022, 27(11), 3631; https://doi.org/10.3390/molecules27113631 - 6 Jun 2022

Cited by 2 | Viewed by 2199

Abstract

In this study, the volatilomes of naturally growing plant leaves were immobilized in a suitable substrate to enhance vapors’ diffusion in the soil to eradicate the Fusarium wilt pathogens in Tomato. Volatilomes produced by Mentha spicata leaves immobilized in vermiculite ball was found [...] Read more.

In this study, the volatilomes of naturally growing plant leaves were immobilized in a suitable substrate to enhance vapors’ diffusion in the soil to eradicate the Fusarium wilt pathogens in Tomato. Volatilomes produced by Mentha spicata leaves immobilized in vermiculite ball was found to be effective and exhibit 92.35 percent inhibition on the mycelial growth of Fusarium oxysporum f. sp. lycopersici (FOL). Moreover, the volatilomes of M. spicata immobilized vermiculite balls were tested based on the distance traveled by the diffused volatilomes from the ball and revealed that the volatilomes of M. spicata traveled up to 20 cm distance from the center of PVC (Polyvinly chloride) chamber showed maximum reduction in colony growth of FOL at 12th day after inoculation. Tomato plants inoculated with FOL revealed increased expressions of defense gene, pathogenesis related protein (PR1) with 2.63-fold after 72 h and the gene, transcription factor (WRKY) increased with 2.5-fold after 48 h on exposure to the volatilomes of M. spicata vermiculite balls. To the best of our knowledge, this is the first report on development of volatilomes based vermiculite ball formulations. This result indicated that the volatilomes of M. spicata are promising phyto-fumigants for management of Tomato Fusarial wilt. Full article

(This article belongs to the Special Issue Antimicrobial Activity of Plant Volatiles in Vapor Phase)

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15 pages, 3267 KiB

Open AccessArticle

Antimicrobial Activity of Dihydroisocoumarin Isolated from Wadi Lajab Sediment-Derived Fungus Penicillium chrysogenum: In Vitro and In Silico Study

by Raha Orfali, Shagufta Perveen, Mohamed Fahad AlAjmI, Safina Ghaffar, Md Tabish Rehman, Abdullah R. AlanzI, Saja Bane Gamea and Mona Essa Khwayri

Molecules 2022, 27(11), 3630; https://doi.org/10.3390/molecules27113630 - 6 Jun 2022

Cited by 10 | Viewed by 2749

Abstract

Antibiotic resistance is considered a major health concern globally. It is a fact that the clinical need for new antibiotics was not achieved until now. One of the most commonly prescribed classes of antibiotics is β-Lactam antibiotics. However, most bacteria have developed resistance [...] Read more.

Antibiotic resistance is considered a major health concern globally. It is a fact that the clinical need for new antibiotics was not achieved until now. One of the most commonly prescribed classes of antibiotics is β-Lactam antibiotics. However, most bacteria have developed resistance against β-Lactams by producing enzymes β-Lactamase or penicillinase. The discovery of new β-Lactamase inhibitors as new antibiotics or antibiotic adjuvants is essential to avoid future catastrophic pandemics. In this study, five dihydroisocoumarin: 6-methoxy mellein (1); 5,6-dihydroxymellein (2); 6-hydroxymellein (3); 4-chloro-6-hydroxymellein (4) and 4-chloro-5,6-di-hydroxymellein (5) were isolated from Wadi Lajab sediment-derived fungus Penicillium chrysogenum, located 15 km northwest of Jazan, KSA. The elucidation of the chemical structures of the isolated compounds was performed by analysis of their NMR, MS. Compounds 1–5 were tested for antibacterial activities against Gram-positive and Gram-negative bacteria. All of the compounds exhibited selective antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Bacillus licheniformis except compound 3. The chloro-dihydroisocoumarin derivative, compound 4, showed potential antimicrobial activities against all of the tested strains with the MIC value between 0.8–5.3 μg/mL followed by compound 5, which exhibited a moderate inhibitory effect. Molecular docking data showed good affinity with the isolated compounds to β-Lactamase enzymes of bacteria; NDM-1, CTX-M, OXA-48. This work provides an effective strategy for compounds to inhibit bacterial growth or overcome bacterial resistance. Full article

(This article belongs to the Special Issue Natural Products: Isolation, Identification and Biological Activity)

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12 pages, 4691 KiB

Open AccessArticle

Poria Acid, Triterpenoids Extracted from Poria cocos, Inhibits the Invasion and Metastasis of Gastric Cancer Cells

by Haibo Wang, Yuanyuan Luo, Zewen Chu, Tengyang Ni, Shiya Ou, Xiaojun Dai, Xiaochun Zhang and Yanqing Liu

Molecules 2022, 27(11), 3629; https://doi.org/10.3390/molecules27113629 - 6 Jun 2022

Cited by 20 | Viewed by 2946

Abstract

Background: Poria cocos (P. cocos) is an important medicinal fungus in traditional Chinese medicine. Poria acid (PA), a triterpenoid compound, is an effective component of traditional Chinese medicine P. cocos. This experiment investigated the anti-gastric cancer biological activity of PA in vitro. [...] Read more.

Background: Poria cocos (P. cocos) is an important medicinal fungus in traditional Chinese medicine. Poria acid (PA), a triterpenoid compound, is an effective component of traditional Chinese medicine P. cocos. This experiment investigated the anti-gastric cancer biological activity of PA in vitro. Methods: The effect of PA on the viability of gastric cancer cells was detected by the thiazolyl blue (MTT) assay. Cell adhesion assays were used to detect changes in the adhesion of cells treated after PA (0, 20, 40, and 80 µmol/L). The ability of cell invasion and migration were detected by Transwell assays and wound healing assays. A high-content imaging system was used to dynamically record the motility of the gastric cancer cells after PA (0, 20, 40, and 80 µmol/L) treatment. Western blotting was used to detect the expression of epithelial–mesenchymal transformation (EMT), invasion and migration related proteins. Results: The MTT assay showed that the proliferation of gastric cancer cells was significantly inhibited after PA treatment. Cell adhesion experiments showed that the adhesion of gastric cancer cells was significantly decreased after PA treatment. Compared with the control group, the wound healing area of the gastric cancer cells treated with different concentrations of PA decreased. The Transwell assay showed that the number of gastric cancer cells passing through the cell membrane were significantly reduced after PA treatment. In addition, after PA treatment, the cells’ movement distance and average movement speed were significantly lower than those of the control group. Finally, PA can significantly alter the expression of EMT-related proteins E-cadherin, N-cadherin, and Vimentin and decreased the expressions of metastasis-related proteins matrix metalloproteinase (MMP) 2, MMP-9 and tissue inhibition of matrix metalloproteinase (TIMP)1 in the gastric cancer cells. Conclusions: Triterpenoids from P. cocos have significant biological activity against gastric cancer, and the mechanism may be involved in the process of epithelial–mesenchymal transformation. Full article

(This article belongs to the Special Issue Plant Bioactive Compounds: Extraction, Identification and Biological Activities)

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16 pages, 2412 KiB

Open AccessArticle

Risk Assessment in Monitoring of Water Analysis of a Brazilian River

by Luciene Pires Brandão, Vanilson Fragoso Silva, Marcelo Bassi and Elcio Cruz de Oliveira

Molecules 2022, 27(11), 3628; https://doi.org/10.3390/molecules27113628 - 6 Jun 2022

Cited by 8 | Viewed by 2357

Abstract

This study aimed to introduce non-parametric tests and guard bands to assess the compliance of some river water properties with Brazilian environmental regulations. Due to the heterogeneity of the measurands pH, Biochemical Oxygen Demand (BOD), manganese molar concentration, and Escherichia coli, which [...] Read more.

This study aimed to introduce non-parametric tests and guard bands to assess the compliance of some river water properties with Brazilian environmental regulations. Due to the heterogeneity of the measurands pH, Biochemical Oxygen Demand (BOD), manganese molar concentration, and Escherichia coli, which could be wrongly treated as outliers, as well as the non-Gaussian data, robust methods were used to calculate the measurement uncertainty. Next, based on guard bands, the compliance assessment was evaluated using this previous uncertainty information. For these four measurands, partial overlaps between their uncertainties and the specification limit could generate doubts about compliance. The non-parametric approach for calculating the uncertainty connected to the guard bands concept classified pH and BOD as “conform”, with a risk to the consumer of up to 4.0% and 4.9%, respectively; in contrast, manganese molar concentration and Escherichia coli were “not conform”, with a risk to the consumer of up to 25% and 7.4%, respectively. The methodology proposed was satisfactory because it considered the natural heterogeneity of data with non-Gaussian behavior instead of wrongly excluding outliers. In an unprecedented way, two connected statistical approaches shed light on the measurement uncertainty in compliance assessment of water analysis. Full article

(This article belongs to the Special Issue Frontiers in Analytical Methods for Water Analysis)

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14 pages, 2352 KiB

Open AccessArticle

Coadsorption Interfered CO Oxidation over Atomically Dispersed Au on h-BN

by Xin Liu, Xin Zhang and Changgong Meng

Molecules 2022, 27(11), 3627; https://doi.org/10.3390/molecules27113627 - 5 Jun 2022

Cited by 5 | Viewed by 1991

Abstract

Similar to the metal centers in biocatalysis and homogeneous catalysis, the metal species in single atom catalysts (SACs) are charged, atomically dispersed and stabilized by support and substrate. The reaction condition dependent catalytic performance of SACs has long been realized, but seldom investigated [...] Read more.

Similar to the metal centers in biocatalysis and homogeneous catalysis, the metal species in single atom catalysts (SACs) are charged, atomically dispersed and stabilized by support and substrate. The reaction condition dependent catalytic performance of SACs has long been realized, but seldom investigated before. We investigated CO oxidation pathways over SACs in reaction conditions using atomically dispersed Au on h-BN (AuBN) as a model with extensive first-principles-based calculations. We demonstrated that the adsorption of reactants, namely CO, O₂ and CO₂, and their coadsorption with reaction species on AuBN would be condition dependent, leading to various reaction species with different reactivity and impact the CO conversion. Specifically, the revised Langmuir–Hinshelwood pathway with the CO-mediated activation of O₂ and dissociation of cyclic peroxide intermediate followed by the Eley–Rideal type reduction is dominant at high temperatures, while the coadsorbed CO-mediated dissociation of peroxide intermediate becomes plausible at low temperatures and high CO partial pressures. Carbonate species would also form in existence of CO₂, react with coadsorbed CO and benefit the conversion. The findings highlight the origin of the condition-dependent CO oxidation performance of SACs in detailed conditions and may help to rationalize the current understanding of the superior catalytic performance of SACs. Full article

(This article belongs to the Section Physical Chemistry)

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14 pages, 1716 KiB

Open AccessArticle

Research on Very Volatile Organic Compounds and Odors from Veneered Medium Density Fiberboard Coated with Water-Based Lacquers

by Weidong Wang, Xiwei Shen, Siqi Zhang, Ruixue Lv, Ming Liu, Wang Xu, Yu Chen and Huiyu Wang

Molecules 2022, 27(11), 3626; https://doi.org/10.3390/molecules27113626 - 5 Jun 2022

Cited by 10 | Viewed by 2309

Abstract

Very volatile organic compounds (VVOCs) are a group of important odor pollutants affecting indoor air quality that have been shown to be harmful to human health. A 15 L environmental chamber, combined with multi-bed tube was used to collect gases. Fifteen very volatile [...] Read more.

Very volatile organic compounds (VVOCs) are a group of important odor pollutants affecting indoor air quality that have been shown to be harmful to human health. A 15 L environmental chamber, combined with multi-bed tube was used to collect gases. Fifteen very volatile organic compounds (VVOCs), including 12 odor compounds, were identified from veneered medium density fiberboard coated with water-based lacquer (WB-MDF) using gas chromatography–mass spectrometry/olfactometry (GC-MS/O). The total very volatile organic compound (TVVOC) and total odor intensity (TOI) showed a decreasing trend over time, reaching equilibrium on day 28. TVVOC showed an overall slow-fast-slow emission profile, from day 3 to day 7, with a maximum decay rate of 29.7%. TOI showed the greatest rate of decline from day 1 to day 3, at approximately 12%. Alkane and alcohol VVOCs were the more abundant compounds, accounting for at least 60% and even up to 80% of the total. The major odor impression was fruity, with a highest odor rating of 6.6, followed by sweet, with an odor rating of 6.1. Although the odor impression changed from sweet to fruity over time, it seemed pleasant overall. The odor contributors were mainly alkanes, alcohols, esters, and ethers, which had relatively high odor intensities. The main odor-contributing substances were dichloromethane, ethanol, ethyl acetate, 2-methylacrylic acid methyl ester, and tetrahydrofuran. When WB-MDF is used for furniture or other decorative materials, it is strongly recommended that it be stored under ventilation for at least 28 days and the adoption of substitute solvents of lacquers, modified adhesives, and low-odor wood raw materials is recommended. These possible initiatives would contribute to the aim of building an environmentally friendly indoor environment. Full article

(This article belongs to the Special Issue Recent Advances in Volatile Organic Compounds Analysis in Various Matrices)

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12 pages, 3271 KiB

Open AccessArticle

Synthesis, Structure and Biological Evaluations of Zn(II) Pincer Complexes Based on S-Triazine Type Chelator

by Heba M. Refaat, Atallh A. M. Alotaibi, Necmi Dege, Ayman El-Faham and Saied M. Soliman

Molecules 2022, 27(11), 3625; https://doi.org/10.3390/molecules27113625 - 5 Jun 2022

Cited by 10 | Viewed by 1904

Abstract

2,4-bis (3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPMT) pincer ligand was used to synthesize the new [Zn(BPMT)(NCS)₂] (1) and [Zn(BPMT)(Br)₂] (2) complexes by a reaction with Zn(NO₃)₂·6H₂O in the [...] Read more.

2,4-bis (3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPMT) pincer ligand was used to synthesize the new [Zn(BPMT)(NCS)₂] (1) and [Zn(BPMT)(Br)₂] (2) complexes by a reaction with Zn(NO₃)₂·6H₂O in the presence of either KSCN or KBr, respectively. The structure of complex 1 has been exclusively confirmed using single crystal X-ray diffraction. In this neutral heteroleptic complex, the BPMT is a pincer chelate coordinating the Zn(II) ion via three interactions with the two pyrazole moieties and the s-triazine core. Hence, BPMT is a tridentate NNN-chelate. The coordination environment of Zn(II) is completed by two strong interactions with two terminal SCN⁻ ions via the N-atom. Hence, the Zn(II) is penta-coordinated with a distorted square pyramidal coordination geometry. Hirshfeld analysis indicated the predominance of H…H, H…C and N…H intermolecular interactions. Additionally, the S…H, S…C and S…N contacts are the most significant. The free ligand has no or weak antimicrobial, antioxidant and anticancer activities while the studied Zn(II) complexes showed interesting biological activity. Complex 1 has excellent antibacterial activity against B. subtilis (2.4 μg/mL) and P. vulgaris (4.8 μg/mL) compared to Gentamycin (4.8 μg/mL). Additionally, complex 1 (78.09 ± 4.23 µg/mL) has better antioxidant activity than 2 (365.60 ± 20.89 µg/mL). In addition, complex 1 (43.86 ± 3.12 µg/mL) and 2 (30.23 ± 1.26 µg/mL) have 8 and 12 times the anticancer activity of the free BPMT ligand (372.79 ± 13.64 µg/mL). Full article

(This article belongs to the Special Issue Metal-Based Complex: Preparation and Medicinal Characteristics)

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25 pages, 3074 KiB

Open AccessArticle

Exploring the Synthetic Potential of γ-Lactam Derivatives Obtained from a Multicomponent Reaction—Applications as Antiproliferative Agents

by Adrián López-Francés, Xabier del Corte, Zuriñe Serna-Burgos, Edorta Martínez de Marigorta, Francisco Palacios and Javier Vicario

Molecules 2022, 27(11), 3624; https://doi.org/10.3390/molecules27113624 - 5 Jun 2022

Cited by 6 | Viewed by 2723

Abstract

A study on the reactivity of 3-amino α,β-unsaturated γ-lactam derivatives obtained from a multicomponent reaction is presented. Key features of the substrates are the presence of an endocyclic α,β-unsaturated amide moiety and an enamine functionality. Following different synthetic protocols, the functionalization at three [...] Read more.

A study on the reactivity of 3-amino α,β-unsaturated γ-lactam derivatives obtained from a multicomponent reaction is presented. Key features of the substrates are the presence of an endocyclic α,β-unsaturated amide moiety and an enamine functionality. Following different synthetic protocols, the functionalization at three different positions of the lactam core is achieved. In the presence of a soft base, under thermodynamic conditions, the functionalization at C-4 takes place where the substrates behave as enamines, while the use of a strong base, under kinetic conditions, leads to the formation of C-5-functionalized γ-lactams, in the presence of ethyl glyoxalate, through a highly diastereoselective vinylogous aldol reaction. Moreover, the nucleophilic addition of organometallic species allows the functionalization at C-3, through the imine tautomer, affording γ-lactams bearing tetrasubstituted stereocenters, where the substrates act as imine electrophiles. Taking into account the advantage of the presence of a chiral stereocenter in C-5 substituted γ-lactams, further diastereoselective transformations are also explored, leading to novel bicyclic substrates holding a fused γ and δ-lactam skeleton. Remarkably, an example of a highly stereoselective formal [3+3] cycloaddition reaction of chiral γ-lactam substrates is reported for the synthesis of 1,4-dihidropyridines, where a non-covalent attractive interaction of a carbonyl group with an electron-deficient arene seems to drive the stereoselectivity of the reaction to the exclusive formation of the cis isomer. In order to unambiguously determine the substitution pattern resulting from the diverse reactions, an extensive characterization of the substrates is detailed through 2D NMR and/or X-ray experiments. Likewise, applications of the substrates as antiproliferative agents against lung and ovarian cancer cells are also described. Full article

(This article belongs to the Special Issue Synthesis, Characterizations and Applications of Bioactive Heterocyclic Compounds)

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14 pages, 1309 KiB

Open AccessArticle

Synthesis and Antiproliferative Activity of Novel Dehydroabietic Acid-Chalcone Hybrids

by Sophia Grigoropoulou, Dimitra Manou, Antonia I. Antoniou, Artemis Tsirogianni, Carlo Siciliano, Achilleas D. Theocharis and Constantinos M. Athanassopoulos

Molecules 2022, 27(11), 3623; https://doi.org/10.3390/molecules27113623 - 5 Jun 2022

Cited by 9 | Viewed by 2747

Abstract

Dehydroabietic Acid (DHA, 1) derivatives are known for their antiproliferative properties, among others. In the context of this work, DHA was initially modified to two key intermediates bearing a C18 methyl ester, a phenol moiety at C12, and an acetyl or formyl [...] Read more.

Dehydroabietic Acid (DHA, 1) derivatives are known for their antiproliferative properties, among others. In the context of this work, DHA was initially modified to two key intermediates bearing a C18 methyl ester, a phenol moiety at C12, and an acetyl or formyl group at C13 position. These derivatives allowed us to synthesize a series of DHA-chalcone hybrids, suitable for structure–activity relationship studies (SARS), following their condensation with a variety of aryl-aldehydes and methyl ketones. The antiproliferative evaluation of the synthesized DHA-chalcone hybrids against three breast cancer cell lines (the estrogen-dependent MCF-7 and the estrogen-independent MDA-MB-231 and Hs578T) showed that eight derivatives (33, 35, 37, 38, 39, 41, 43, 44) exhibit low micromolar activity levels (IC₅₀ 2.21–11.5 μΜ/MCF-7). For instance, some of them showed better activity compared to the commercial anticancer drug 5-FU against MCF-7 cells (33, 41, 43, 44) and against MDA-MB231 (33 and 41). Hybrid 38 is a promising lead compound for the treatment of MCF-7 breast cancer, exhibiting comparable activity to 5-FU and being 12.9 times less toxic (SI = 22.7). Thus, our findings suggest that DHA-chalcone hybrids are drug candidates worth pursuing for further development in the search for novel breast cancer therapies. Full article

(This article belongs to the Special Issue Discovery, Synthesis and Evaluation of Bioactive Compounds)

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16 pages, 1889 KiB

Open AccessArticle

Interactive Effects of Molybdenum, Zinc and Iron on the Grain Yield, Quality, and Nodulation of Cowpea (Vignaunguiculata (L.) Walp.) in North-Western India

by Salwinder Singh Dhaliwal, Vivek Sharma, Arvind Kumar Shukla, Janpriya Kaur, Vibha Verma, Manmeet Kaur, Prabhjot Singh, Marian Brestic, Ahmed Gaber and Akbar Hossain

Molecules 2022, 27(11), 3622; https://doi.org/10.3390/molecules27113622 - 5 Jun 2022

Cited by 7 | Viewed by 2480

Abstract

Micronutrient deficiency is a major constraint for the growth, yield and nutritional quality of cowpea which results in nutritional disorders in humans. Micronutrients including molybdenum (Mo), iron (Fe) and zinc (Zn) play a pivotal role in crop nutrition, and their role in different [...] Read more.

Micronutrient deficiency is a major constraint for the growth, yield and nutritional quality of cowpea which results in nutritional disorders in humans. Micronutrients including molybdenum (Mo), iron (Fe) and zinc (Zn) play a pivotal role in crop nutrition, and their role in different metabolic processes in crops has been highlighted. In order to increase the nutritional quality of cowpea, a field experiment was conducted for two years in which the effect of Mo along with iron (Fe) and zinc (Zn) on productivity, nitrogen and micronutrient uptake, root length and the number of nodules in cowpea cultivation was investigated. It was found that the foliar application of Fe and Zn and their interaction with Mo application through seed priming as well as soil application displayed increased yield, nutrient concentration, uptake and growth parameters which helped to enhance the nutritional quality of cowpea for consumption by the human population. The results of the above experiments revealed that among all the treatments, the soil application of Mo combined with the foliar application of 0.5% each of FeSO₄·7H₂O and ZnSO₄·7H₂O (M₂F₃ treatment) enhanced the grain and stover yield of cowpea, exhibiting maximum values of 1402 and 6104.7 kg ha⁻¹, respectively. Again, the M₂F₃ treatment resulted in higher Zn, Fe and Mo concentrations in the grain (17.07, 109.3 and 30.26 mg kg⁻¹, respectively) and stover (17.99, 132.7 and 31.22 mg kg⁻¹, respectively) of cowpea. Uptake of Zn, Fe and Mo by the grain (25.23, 153.3 and 42.46 g ha⁻¹, respectively) as well as the stover (104.2, 809.9 and 190.6 g ha⁻¹, respectively) was found to be maximum for the M₂F₃ treatment. The root length (30.5 cm), number of nodules per plant (73.0) and N uptake in grain and stover (55.39 and 46.15 kg ha⁻¹) were also higher for this treatment. Overall, soil application of Mo along with the foliar application of FeSO₄·7H₂O (0.5%) and ZnSO₄·7H₂O (0.5%) significantly improved yield outcomes, concentration, uptake, root length, nodules plant⁻¹ and N uptake of cowpea to alleviate the micronutrient deficiency. Full article

(This article belongs to the Special Issue Food Bioactive Compounds: Chemical Challenges and Opportunities)

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21 pages, 6314 KiB

Open AccessReview

Methods of Betulin Extraction from Birch Bark

by Olga V. Demets, Altynaray T. Takibayeva, Rymchan Z. Kassenov and Madina R. Aliyeva

Molecules 2022, 27(11), 3621; https://doi.org/10.3390/molecules27113621 - 5 Jun 2022

Cited by 26 | Viewed by 4816

Abstract

Betulin is the most popular of the known triterpenoids of the lupan series. It has valuable pharmacological properties. It exhibits antibacterial, antiviral, antitumor, hypolipidemic and other types of activity. The prospects of using betulin in medicine, pharmacology, and veterinary medicine require the development [...] Read more.

Betulin is the most popular of the known triterpenoids of the lupan series. It has valuable pharmacological properties. It exhibits antibacterial, antiviral, antitumor, hypolipidemic and other types of activity. The prospects of using betulin in medicine, pharmacology, and veterinary medicine require the development of effective methods for obtaining it from waste from the woodworking industry. Therefore, the question arises of the need to develop a technology for isolating and purifying triterpenoids from birch bark in large quantities. This review contains a variety of methods for the isolation of betulin. The advantages and disadvantages of the proposed methods are described. The following methods are considered: vacuum sublimation after preliminary alkaline; vacuum pyrolysis; supercritical extraction with carbon dioxide or mixtures of carbon dioxide with various solvents; extraction with organic solvents. Also, the method of microwave is described, it is activation on the example of the Kyrgyz birch (Betula kirghisorum), this is an endemic species that has not been studied before, growing on the territory of the Republic of Kazakhstan. Full article

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18 pages, 1026 KiB

Open AccessArticle

nor 3′-Demethoxyisoguaiacin from Larrea tridentata Is a Potential Alternative against Multidrug-Resistant Bacteria Associated with Bovine Mastitis

by Ana Lizet Morales-Ubaldo, Manases Gonzalez-Cortazar, Adrian Zaragoza-Bastida, Martín A. Meza-Nieto, Benjamín Valladares-Carranza, Abdulrahman A. Alsayegh, Gaber El-Saber Batiha and Nallely Rivero-Perez

Molecules 2022, 27(11), 3620; https://doi.org/10.3390/molecules27113620 - 5 Jun 2022

Cited by 6 | Viewed by 2527

Abstract

Bovine mastitis is one of the most common diseases in dairy cows, and it causes significant economic losses in dairy industries worldwide. Gram-positive and Gram-negative bacteria can cause bovine mastitis, and many of them have developed antimicrobial resistance. There is an urgent need [...] Read more.

Bovine mastitis is one of the most common diseases in dairy cows, and it causes significant economic losses in dairy industries worldwide. Gram-positive and Gram-negative bacteria can cause bovine mastitis, and many of them have developed antimicrobial resistance. There is an urgent need for novel therapeutic options to treat the disease. Larrea tridentata-derived compounds represent an important potential alternative treatment. The aim of the present study was to isolate and characterize antibacterial compounds from Larrea tridentata against multidrug-resistant bacteria associated with bovine mastitis. The L. tridentata hydroalcoholic extract (LTHE) exhibited antibacterial activity. The extract was subjected to a bipartition, giving an aqueous fraction (moderate antibacterial activity) and an organic fraction (higher antibacterial activity). Chromatographic separation of the organic fraction enabled us to obtain four active sub-fractions. Chemical analyses through HPLC techniques were conducted for the LTHE, fractions, and sub-fraction Ltc1-F3, from which we isolated two compounds, characterized by ¹H and ¹³C NMR analyses. Compound nor-3 demethoxyisoguaiacin exhibited the best antibacterial activity against the evaluated bacteria (MIC: 0.01–3.12 mg/mL; MBC: 0.02–3.12 mg/mL). The results indicated that nor-3 demethoxyisoguaiacin can be used as an alternative treatment for multidrug-resistant bacteria associated with mastitis. Full article

(This article belongs to the Special Issue Bioactive Compounds from Natural Resources)

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19 pages, 9568 KiB

Open AccessArticle

Molecular Dynamic Study of Mechanism Underlying Nature of Molecular Recognition and the Role of Crosslinker in the Synthesis of Salmeterol-Targeting Molecularly Imprinted Polymer for Analysis of Salmeterol Xinafoate in Biological Fluid

by Shendi Suryana, Mutakin Mutakin, Yudi Rosandi and Aliya Nur Hasanah

Molecules 2022, 27(11), 3619; https://doi.org/10.3390/molecules27113619 - 5 Jun 2022

Cited by 8 | Viewed by 2543

Abstract

The rational preparation of molecularly imprinted polymers (MIPs) in order to have selective extraction of salmeterol xinafoate (SLX) from serum was studied. SLX is an acting β-adrenergic receptor agonist used in the treatment of asthma and has an athletic performance-enhancing effect. Molecular dynamics [...] Read more.

The rational preparation of molecularly imprinted polymers (MIPs) in order to have selective extraction of salmeterol xinafoate (SLX) from serum was studied. SLX is an acting β-adrenergic receptor agonist used in the treatment of asthma and has an athletic performance-enhancing effect. Molecular dynamics were used for the simulation of the SLX-imprinted pre-polymerization system, to determine the stability of the system. The computational simulation showed that SLX as a template, 4-hydroxyethyl methacrylate (HEMA) as a monomer, and trimethylolpropane trimethacrylate (TRIM) as a crosslinker in mol ratio of 1:6:20 had the strongest interaction in terms of the radial distribution functional. To validate the computational result, four polymers were synthesized using the precipitation polymerization method, and MIP with composition and ratio corresponding with the system with the strongest interaction as an MD simulation result showed the best performance, with a recovery of 96.59 ± 2.24% of SLX in spiked serum and 92.25 ± 1.12% when SLX was spiked with another analogue structure. Compared with the standard solid phase extraction sorbent C-18, which had a recovery of 79.11 ± 2.96%, the MIP showed better performance. The harmony between the simulation and experimental results illustrates that the molecular dynamic simulations had a significant role in the study and development of the MIPs for analysis of SLX in biological fluid. Full article

(This article belongs to the Special Issue Advances in Analytical Sample Preparation Using Sorbent/Solid Phase Materials as Extraction Media)

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11 pages, 5354 KiB

Open AccessArticle

Effect of Wearing Surgical Face Masks on Gas Detection from Respiration Using Photoacoustic Spectroscopy

by Cristina Popa, Mioara Petrus and Ana Maria Bratu

Molecules 2022, 27(11), 3618; https://doi.org/10.3390/molecules27113618 - 4 Jun 2022

Cited by 9 | Viewed by 2349

Abstract

Wearing surgical face masks is among the measures taken to mitigate coronavirus disease (COVID-19) transmission and deaths. Lately, concern was expressed about the possibility that gases from respiration could build up in the mask over time, causing medical issues related to the respiratory [...] Read more.

Wearing surgical face masks is among the measures taken to mitigate coronavirus disease (COVID-19) transmission and deaths. Lately, concern was expressed about the possibility that gases from respiration could build up in the mask over time, causing medical issues related to the respiratory system. In this research study, the carbon dioxide concentration and ethylene in the breathing zone were measured before and immediately after wearing surgical face masks using the photoacoustic spectroscopy method. From the determinations of this study, the C₂H₄ was established to be increased by 1.5% after one hour of wearing the surgical face mask, while CO₂ was established to be at a higher concentration of 1.2% after one hour of wearing the surgical face mask, when the values were correlated with the baseline (control). Full article

(This article belongs to the Special Issue Spectroscopic Investigations of Novel Pharmaceuticals)

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