Molecules

8 pages, 1326 KiB

Open AccessArticle

Synthesis and Anticancer Cytotoxicity of Azaaurones Overcoming Multidrug Resistance

by Szilárd Tóth, Áron Szepesi, Viet-Khoa Tran-Nguyen, Balázs Sarkadi, Katalin Német, Pierre Falson, Attilio Di Pietro, Gergely Szakács and Ahcène Boumendjel

Molecules 2020, 25(3), 764; https://doi.org/10.3390/molecules25030764 - 10 Feb 2020

Cited by 24 | Viewed by 4751

Abstract

The resistance of tumors against anticancer drugs is a major impediment for chemotherapy. Tumors often develop multidrug resistance as a result of the cellular efflux of chemotherapeutic agents by ABC transporters such as P-glycoprotein (ABCB1/P-gp), Multidrug Resistance Protein 1 (ABCC1/MRP1), or Breast Cancer [...] Read more.

The resistance of tumors against anticancer drugs is a major impediment for chemotherapy. Tumors often develop multidrug resistance as a result of the cellular efflux of chemotherapeutic agents by ABC transporters such as P-glycoprotein (ABCB1/P-gp), Multidrug Resistance Protein 1 (ABCC1/MRP1), or Breast Cancer Resistance Protein (ABCG2/BCRP). By screening a chemolibrary comprising 140 compounds, we identified a set of naturally occurring aurones inducing higher cytotoxicity against P-gp-overexpressing multidrug-resistant (MDR) cells versus sensitive (parental, non-P-gp-overexpressing) cells. Follow-up studies conducted with the P-gp inhibitor tariquidar indicated that the MDR-selective toxicity of azaaurones is not mediated by P-gp. Azaaurone analogs possessing pronounced effects were then designed and synthesized. The knowledge gained from structure–activity relationships will pave the way for the design of a new class of anticancer drugs selectively targeting multidrug-resistant cancer cells. Full article

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16 pages, 3030 KiB

Open AccessArticle

Discrimination of Cultivated Regions of Soybeans (Glycine max) Based on Multivariate Data Analysis of Volatile Metabolite Profiles

by So-Yeon Kim, So Young Kim, Sang Mi Lee, Do Yup Lee, Byeung Kon Shin, Dong Jin Kang, Hyung-Kyoon Choi and Young-Suk Kim

Molecules 2020, 25(3), 763; https://doi.org/10.3390/molecules25030763 - 10 Feb 2020

Cited by 20 | Viewed by 5149

Abstract

Soybean (Glycine max) is a major crop cultivated in various regions and consumed globally. The formation of volatile compounds in soybeans is influenced by the cultivar as well as environmental factors, such as the climate and soil in the cultivation areas. [...] Read more.

Soybean (Glycine max) is a major crop cultivated in various regions and consumed globally. The formation of volatile compounds in soybeans is influenced by the cultivar as well as environmental factors, such as the climate and soil in the cultivation areas. This study used gas chromatography-mass spectrometry (GC-MS) combined by headspace solid-phase microextraction (HS-SPME) to analyze the volatile compounds of soybeans cultivated in Korea, China, and North America. The multivariate data analysis of partial least square-discriminant analysis (PLS-DA), and hierarchical clustering analysis (HCA) were then applied to GC-MS data sets. The soybeans could be clearly discriminated according to their geographical origins on the PLS-DA score plot. In particular, 25 volatile compounds, including terpenes (limonene, myrcene), esters (ethyl hexanoate, butyl butanoate, butyl prop-2-enoate, butyl acetate, butyl propanoate), aldehydes (nonanal, heptanal, (E)-hex-2-enal, (E)-hept-2-enal, acetaldehyde) were main contributors to the discrimination of soybeans cultivated in China from those cultivated in other regions in the PLS-DA score plot. On the other hand, 15 volatile compounds, such as 2-ethylhexan-1-ol, 2,5-dimethylhexan-2-ol, octanal, and heptanal, were related to Korean soybeans located on the negative PLS 2 axis, whereas 12 volatile compounds, such as oct-1-en-3-ol, heptan-4-ol, butyl butanoate, and butyl acetate, were responsible for North American soybeans. However, the multivariate statistical analysis (PLS-DA) was not able to clearly distinguish soybeans cultivated in Korea, except for those from the Gyeonggi and Kyeongsangbuk provinces. Full article

(This article belongs to the Special Issue Progress in Volatile Organic Compounds Research)

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35 pages, 1953 KiB

Open AccessReview

Therapeutic Potential of Flavonoids in Pain and Inflammation: Mechanisms of Action, Pre-Clinical and Clinical Data, and Pharmaceutical Development

by Camila R. Ferraz, Thacyana T. Carvalho, Marília F. Manchope, Nayara A. Artero, Fernanda S. Rasquel-Oliveira, Victor Fattori, Rubia Casagrande and Waldiceu A. Verri, Jr.

Molecules 2020, 25(3), 762; https://doi.org/10.3390/molecules25030762 - 10 Feb 2020

Cited by 239 | Viewed by 21377

Abstract

Pathological pain can be initiated after inflammation and/or peripheral nerve injury. It is a consequence of the pathological functioning of the nervous system rather than only a symptom. In fact, pain is a significant social, health, and economic burden worldwide. Flavonoids are plant [...] Read more.

Pathological pain can be initiated after inflammation and/or peripheral nerve injury. It is a consequence of the pathological functioning of the nervous system rather than only a symptom. In fact, pain is a significant social, health, and economic burden worldwide. Flavonoids are plant derivative compounds easily found in several fruits and vegetables and consumed in the daily food intake. Flavonoids vary in terms of classes, and while structurally unique, they share a basic structure formed by three rings, known as the flavan nucleus. Structural differences can be found in the pattern of substitution in one of these rings. The hydroxyl group (–OH) position in one of the rings determines the mechanisms of action of the flavonoids and reveals a complex multifunctional activity. Flavonoids have been widely used for their antioxidant, analgesic, and anti-inflammatory effects along with safe preclinical and clinical profiles. In this review, we discuss the preclinical and clinical evidence on the analgesic and anti-inflammatory proprieties of flavonoids. We also focus on how the development of formulations containing flavonoids, along with the understanding of their structure-activity relationship, can be harnessed to identify novel flavonoid-based therapies to treat pathological pain and inflammation. Full article

(This article belongs to the Special Issue Flavonoids and Their Disease Prevention and Treatment Potential)

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12 pages, 3002 KiB

Open AccessArticle

Direct Recovery of the Rare Earth Elements Using a Silk Displaying a Metal-Recognizing Peptide

by Nobuhiro Ishida, Takaaki Hatanaka, Yoichi Hosokawa, Katsura Kojima, Tetsuya Iizuka, Hidetoshi Teramoto, Hideki Sezutsu and Tsunenori Kameda

Molecules 2020, 25(3), 761; https://doi.org/10.3390/molecules25030761 - 10 Feb 2020

Cited by 5 | Viewed by 4591

Abstract

Rare earth elements (RE) are indispensable metallic resources in the production of advanced materials; hence, a cost- and energy-effective recovery process is required to meet the rapidly increasing RE demand. Here, we propose an artificial RE recovery approach that uses a functional silk [...] Read more.

Rare earth elements (RE) are indispensable metallic resources in the production of advanced materials; hence, a cost- and energy-effective recovery process is required to meet the rapidly increasing RE demand. Here, we propose an artificial RE recovery approach that uses a functional silk displaying a RE-recognizing peptide. Using the piggyBac system, we constructed a transgenic silkworm in which one or two copies of the gene coding for the RE-recognizing peptide (Lamp1) was fused with that of the fibroin L (FibL) protein. The purified FibL-Lamp1 fusion protein from the transgenic silkworm was able to recognize dysprosium (Dy³⁺), a RE, under physiological conditions. This method can also be used with silk from which sericin has been removed. Furthermore, the Dy-recovery ability of this silk was significantly improved by crushing the silk. Our simple approach is expected to facilitate the direct recovery of RE from an actual mixed solution of metal ions, such as seawater and industrial wastewater, under mild conditions without additional energy input. Full article

(This article belongs to the Special Issue Silk Fibroin Materials)

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19 pages, 5817 KiB

Open AccessArticle

Anticancer Activities of the Quinone-Methide Triterpenes Maytenin and 22-β-hydroxymaytenin Obtained from Cultivated Maytenus ilicifolia Roots Associated with Down-Regulation of miRNA-27a and miR-20a/miR-17-5p

by Camila Hernandes, Lucyene Miguita, Romario Oliveira de Sales, Elisangela de Paula Silva, Pedro Omori Ribeiro de Mendonça, Bruna Lorencini da Silva, Maria de Fatima Guarizo Klingbeil, Monica Beatriz Mathor, Erika Bevilaqua Rangel, Luciana Cavalheiro Marti, Juliana da Silva Coppede, Fabio Daumas Nunes, Ana Maria Soares Pereira and Patricia Severino

Molecules 2020, 25(3), 760; https://doi.org/10.3390/molecules25030760 - 10 Feb 2020

Cited by 17 | Viewed by 4827

Abstract

Natural triterpenes exhibit a wide range of biological activities. Since this group of secondary metabolites is structurally diverse, effects may vary due to distinct biochemical interactions within biological systems. In this work, we investigated the anticancer-related activities of the quinone-methide triterpene maytenin and [...] Read more.

Natural triterpenes exhibit a wide range of biological activities. Since this group of secondary metabolites is structurally diverse, effects may vary due to distinct biochemical interactions within biological systems. In this work, we investigated the anticancer-related activities of the quinone-methide triterpene maytenin and its derivative compound 22-β-hydroxymaytenin, obtained from Maytenus ilicifolia roots cultivated in vitro. Their antiproliferative and pro-apoptotic activities were evaluated in monolayer and three-dimensional cultures of immortalized cell lines. Additionally, we investigated the toxicity of maytenin in SCID mice harboring tumors derived from a squamous cell carcinoma cell line. Both isolated molecules presented pronounced pro-apoptotic activities in four cell lines derived from head and neck squamous cell carcinomas, including a metastasis-derived cell line. The molecules also induced reactive oxygen species (ROS) and down-regulated microRNA-27a and microRNA-20a/miR-17-5p, corroborating with the literature data for triterpenoids. Intraperitoneal administration of maytenin to tumor-bearing mice did not lead to pronounced histopathological changes in kidney tissue, suggesting low nephrotoxicity. The wide-ranging activity of maytenin and 22-β-hydroxymaytenin in head and neck cancer cells indicates that these molecules should be further explored in plant biochemistry and biotechnology for therapeutic applications. Full article

(This article belongs to the Special Issue Natural Bioactive Molecules and Toxins from Marine and Terrestrial Origin)

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18 pages, 6292 KiB

Open AccessArticle

Stabilizing the Oil-in-Water Emulsions Using the Mixtures of Dendrobium Officinale Polysaccharides and Gum Arabic or Propylene Glycol Alginate

by Bo Wang, Haiyan Tian and Dong Xiang

Molecules 2020, 25(3), 759; https://doi.org/10.3390/molecules25030759 - 10 Feb 2020

Cited by 43 | Viewed by 8090

Abstract

Coconut oil-in-water emulsions were prepared using three polysaccharides: Dendrobium officinale polysaccharide (DOP), propylene glycol alginate (PGA), gum arabic (GA) and their polysaccharide complexes as emulsifiers. The effects of the ratio of the compounded polysaccharides on their apparent viscosity and interfacial activity were explored [...] Read more.

Coconut oil-in-water emulsions were prepared using three polysaccharides: Dendrobium officinale polysaccharide (DOP), propylene glycol alginate (PGA), gum arabic (GA) and their polysaccharide complexes as emulsifiers. The effects of the ratio of the compounded polysaccharides on their apparent viscosity and interfacial activity were explored in this study. The average particle size, zeta potential, microstructure, rheological properties, and physical stability of the emulsions prepared with different compound-polysaccharides were studied. The results showed that mainly DOP contributed to the apparent viscosity of the compound-polysaccharide, while the interfacial activity and zeta potential were mainly influenced by PGA or GA. Emulsions prepared with compound-polysaccharides exhibited smaller average particle sizes, and microscopic observations showed smaller droplets and less droplet aggregation. In addition, the stability analysis of emulsions by a dispersion analyzer LUMiSizer showed that the emulsion prepared by compounding polysaccharides had better physical stability. Finally, all of the above experimental results showed that the emulsions prepared by PGA:DOP = 2:8 (total concentration = 1.5 wt%) and 2.0% GA + 1.5% DOP were the most stable. Full article

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10 pages, 2605 KiB

Open AccessReview

Bone Mineral Affinity of Polyphosphodiesters

by Yasuhiko Iwasaki

Molecules 2020, 25(3), 758; https://doi.org/10.3390/molecules25030758 - 10 Feb 2020

Cited by 19 | Viewed by 4736

Abstract

Biomimetic molecular design is a promising approach for generating functional biomaterials such as cell membrane mimetic blood-compatible surfaces, mussel-inspired bioadhesives, and calcium phosphate cements for bone regeneration. Polyphosphoesters (PPEs) are candidate biomimetic polymer biomaterials that are of interest due to their biocompatibility, biodegradability, [...] Read more.

Biomimetic molecular design is a promising approach for generating functional biomaterials such as cell membrane mimetic blood-compatible surfaces, mussel-inspired bioadhesives, and calcium phosphate cements for bone regeneration. Polyphosphoesters (PPEs) are candidate biomimetic polymer biomaterials that are of interest due to their biocompatibility, biodegradability, and structural similarity to nucleic acids. While studies on the synthesis of PPEs began in the 1970s, the scope of their use as biomaterials has increased in the last 20 years. One advantageous property of PPEs is their molecular diversity due to the presence of multivalent phosphorus in their backbones, which allows their physicochemical and biointerfacial properties to be easily controlled to produce the desired molecular platforms for functional biomaterials. Polyphosphodiesters (PPDEs) are analogs of PPEs that have recently attracted interest due to their strong affinity for biominerals. This review describes the fundamental properties of PPDEs and recent research in the field of macromolecular bone therapeutics. Full article

(This article belongs to the Special Issue Phosphorus-Containing Materials and Polymers: How a Central Element of All Living Matter can be Used in the Synthetic World)

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15 pages, 5676 KiB

Open AccessArticle

Quercetin Inhibits Cell Survival and Metastatic Ability via the EMT-Mediated Pathway in Oral Squamous Cell Carcinoma

by So Ra Kim, Eun Young Lee, Da Jeong Kim, Hye Jung Kim and Hae Ryoun Park

Molecules 2020, 25(3), 757; https://doi.org/10.3390/molecules25030757 - 10 Feb 2020

Cited by 35 | Viewed by 5594

Abstract

This study aimed to investigate whether quercetin exerts anticancer effects on oral squamous cell carcinoma (OSCC) cell lines and to elucidate its mechanism of action. These anticancer effects in OSCC cells were assessed using an MTT assay, flow cytometry (to assess the cell [...] Read more.

This study aimed to investigate whether quercetin exerts anticancer effects on oral squamous cell carcinoma (OSCC) cell lines and to elucidate its mechanism of action. These anticancer effects in OSCC cells were assessed using an MTT assay, flow cytometry (to assess the cell cycle), wound-healing assay, invasion assay, Western blot analysis, gelatin zymography, and immunofluorescence. To investigate whether quercetin also inhibits transforming growth factor β1 (TGF-β1)-induced epithelial–mesenchymal transition (EMT) in human keratinocyte cells, HaCaT cells were treated with TGF-β1. Overall, our results strongly suggest that quercetin suppressed the viability of OSCC cells by inducing cell cycle arrest at the G2/M phase. However, quercetin did not affect cell viability of human keratinocytes such as HaCaT (immortal keratinocyte) and nHOK (primary normal human oral keratinocyte) cells. Additionally, quercetin suppresses cell migration through EMT and matrix metalloproteinase (MMP) in OSCC cells and decreases TGF-β1-induced EMT in HaCaT cells. In conclusion, this study is the first, to our knowledge, to demonstrate that quercetin can inhibit the survival and metastatic ability of OSCC cells via the EMT-mediated pathway, specifically Slug. Quercetin may thus provide a novel pharmacological approach for the treatment of OSCCs. Full article

(This article belongs to the Special Issue Antitumor and Anti-HIV Agents from Natural Products)

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20 pages, 14933 KiB

Open AccessArticle

An Interpenetrating Alginate/Gelatin Network for Three-Dimensional (3D) Cell Cultures and Organ Bioprinting

by Qiuhong Chen, Xiaohong Tian, Jun Fan, Hao Tong, Qiang Ao and Xiaohong Wang

Molecules 2020, 25(3), 756; https://doi.org/10.3390/molecules25030756 - 10 Feb 2020

Cited by 66 | Viewed by 7949

Abstract

Crosslinking is an effective way to improve the physiochemical and biochemical properties of hydrogels. In this study, we describe an interpenetrating polymer network (IPN) of alginate/gelatin hydrogels (i.e., A-G-IPN) in which cells can be encapsulated for in vitro three-dimensional (3D) cultures and organ [...] Read more.

Crosslinking is an effective way to improve the physiochemical and biochemical properties of hydrogels. In this study, we describe an interpenetrating polymer network (IPN) of alginate/gelatin hydrogels (i.e., A-G-IPN) in which cells can be encapsulated for in vitro three-dimensional (3D) cultures and organ bioprinting. A double crosslinking model, i.e., using Ca²⁺ to crosslink alginate molecules and transglutaminase (TG) to crosslink gelatin molecules, is exploited to improve the physiochemical, such as water holding capacity, hardness and structural integrity, and biochemical properties, such as cytocompatibility, of the alginate/gelatin hydrogels. For the sake of convenience, the individual ionic (i.e., only treatment with Ca²⁺) or enzymatic (i.e., only treatment with TG) crosslinked alginate/gelatin hydrogels are referred as alginate-semi-IPN (i.e., A-semi-IPN) or gelatin-semi-IPN (i.e., G-semi-IPN), respectively. Tunable physiochemical and biochemical properties of the hydrogels have been obtained by changing the crosslinking sequences and polymer concentrations. Cytocompatibilities of the obtained hydrogels are evaluated through in vitro 3D cell cultures and bioprinting. The double crosslinked A-G-IPN hydrogel is a promising candidate for a wide range of biomedical applications, including bioartificial organ manufacturing, high-throughput drug screening, and pathological mechanism analyses. Full article

(This article belongs to the Special Issue Biomedical Hydrogels: Synthesis and Applications)

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15 pages, 1084 KiB

Open AccessArticle

An Optimised Di-Boronate-ChemMatrix Affinity Chromatography to Trap Deoxyfructosylated Peptides as Biomarkers of Glycation

by Monika Kijewska, Francesca Nuti, Magdalena Wierzbicka, Mateusz Waliczek, Patrycja Ledwoń, Agnieszka Staśkiewicz, Feliciana Real-Fernandez, Giuseppina Sabatino, Paolo Rovero, Piotr Stefanowicz, Zbigniew Szewczuk and Anna Maria Papini

Molecules 2020, 25(3), 755; https://doi.org/10.3390/molecules25030755 - 10 Feb 2020

Cited by 12 | Viewed by 5519

Abstract

We report herein a novel ChemMatrix^® Rink resin functionalised with two phenylboronate (PhB) moieties linked on the N-α and N-ε amino functions of a lysine residue to specifically capture deoxyfructosylated peptides, compared to differently glycosylated peptides in complex mixtures. The [...] Read more.

We report herein a novel ChemMatrix^® Rink resin functionalised with two phenylboronate (PhB) moieties linked on the N-α and N-ε amino functions of a lysine residue to specifically capture deoxyfructosylated peptides, compared to differently glycosylated peptides in complex mixtures. The new PhB-Lys(PhB)-ChemMatrix^® Rink resin allows for exploitation of the previously demonstrated ability of cis diols to form phenylboronic esters. The optimised capturing and cleavage procedure from the novel functionalised resin showed that only the peptides containing deoxyfructosyl-lysine moieties can be efficiently and specifically detected by HR-MS and MS/MS experiments. We also investigated the high-selective affinity to deoxyfructosylated peptides in an ad hoc mixture containing unique synthetic non-modified peptides and in the hydrolysates of human and bovine serum albumin as complex peptide mixtures. We demonstrated that the deoxyfructopyranosyl moiety on lysine residues is crucial in the capturing reaction. Therefore, the novel specifically-designed PhB-Lys(PhB)-ChemMatrix^® Rink resin, which has the highest affinity to deoxyfructosylated peptides, is a candidate to quantitatively separate early glycation peptides from complex mixtures to investigate their role in diabetes complications in the clinics. Full article

(This article belongs to the Section Bioorganic Chemistry)

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10 pages, 1446 KiB

Open AccessArticle

Effect of Polyvinyl Alcohol on the Rheological Properties of Cement Mortar

by Fang Liu, Baomin Wang, Yunqing Xing, Kunkun Zhang and Wei Jiang

Molecules 2020, 25(3), 754; https://doi.org/10.3390/molecules25030754 - 10 Feb 2020

Cited by 32 | Viewed by 4693

Abstract

Polyvinyl alcohol (PVA) is a kind of water-soluble polymer, which has been widely used in different industries due to its excellent mechanical and chemical properties. In this paper, the effects of polyvinyl alcohol with different hydrolysis and polymerization degrees on the rheological properties [...] Read more.

Polyvinyl alcohol (PVA) is a kind of water-soluble polymer, which has been widely used in different industries due to its excellent mechanical and chemical properties. In this paper, the effects of polyvinyl alcohol with different hydrolysis and polymerization degrees on the rheological properties of cement mortar are studied. The results show that the rheological properties of PVA-modified cement mortar can be described by the modified Bingham model. The yield stress of modified cement mortar is less than that of unmodified mortar when the degree of polymerization and the content of PVA are small. With the increase of polyvinyl alcohol content and polymerization degree, the yield stress and plastic viscosity of modified cement mortar increase sharply, which are larger than those of the unmodified cement mortar. However, the effect of hydrolysis degree of PVA on yield stress and plastic viscosity of modified cement mortar is not obvious. Full article

(This article belongs to the Special Issue Structural Mechanics of Composite Materials and Structures)

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12 pages, 2502 KiB

Open AccessArticle

Melatonin Accumulation in Sweet Cherry and Its Influence on Fruit Quality and Antioxidant Properties

by Hui Xia, Yanqiu Shen, Tian Shen, Xin Wang, Xuefeng Zhang, Peng Hu, Dong Liang, Lijin Lin, Honghong Deng, Jin Wang, Qunxian Deng and Xiulan Lv

Molecules 2020, 25(3), 753; https://doi.org/10.3390/molecules25030753 - 10 Feb 2020

Cited by 69 | Viewed by 6260

Abstract

Although the effects of melatonin on plant abiotic and biotic stress resistance have been explored in recent decades, the accumulation of endogenous melatonin in plants and its influence on fruit quality remains unclear. In the present study, melatonin accumulation levels and the expression [...] Read more.

Although the effects of melatonin on plant abiotic and biotic stress resistance have been explored in recent decades, the accumulation of endogenous melatonin in plants and its influence on fruit quality remains unclear. In the present study, melatonin accumulation levels and the expression profiles of five synthesis genes were investigated during fruit and leaf development in sweet cherry (Prunus avium L.). Melatonin was strongly accumulated in young fruits and leaves, then decreased steadily with maturation. Transcript levels of PacTDC and PacSNAT were highly correlated with melatonin content in both fruit and leaves, indicating their importance in melatonin accumulation. Furthermore, application of 50 and 100 μmol·L⁻¹ of melatonin to leaves had a greater influence on fruit quality than treatments applied to fruits, by significantly improving fruit weight, soluble solids content, and phenolic content including total phenols, flavanols, total anthocyanins, and ascorbic acid. Meanwhile, melatonin application promoted the antioxidant capacity of fruit assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis (3-ethylben zothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP). These results provide insights into the physiological and molecular mechanisms underlying melatonin metabolism of sweet cherry. Full article

(This article belongs to the Section Chemical Biology)

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18 pages, 5347 KiB

Open AccessReview

Analytical Approaches for Analysis of Safety of Modern Food Packaging: A Review

by Magdalena Wrona and Cristina Nerín

Molecules 2020, 25(3), 752; https://doi.org/10.3390/molecules25030752 - 10 Feb 2020

Cited by 61 | Viewed by 9783

Abstract

Nowadays, food packaging is a crucial tool for preserving food quality and has become an inseparable part of our daily life. Strong consumer demand and market trends enforce more advanced and creative forms of food packaging. New packaging development requires safety evaluations that [...] Read more.

Nowadays, food packaging is a crucial tool for preserving food quality and has become an inseparable part of our daily life. Strong consumer demand and market trends enforce more advanced and creative forms of food packaging. New packaging development requires safety evaluations that always implicate the application of complex analytical methods. The present work reviews the development and application of new analytical methods for detection of possible food contaminants from the packaging origin on the quality and safety of fresh food. Among food contaminants migrants, set-off migrants from printing inks, polymer degradation products, and aromatic volatile compounds can be found that may compromise the safety and organoleptic properties of food. The list of possible chemical migrants is very wide and includes antioxidants, antimicrobials, intentionally added substances (IAS), non-intentionally added substances (NIAS), monomers, oligomers, and nanoparticles. All this information collected prior to the analysis will influence the type of analyzing samples and molecules (analytes) and therefore the selection of a convenient analytical method. Different analytical strategies will be discussed, including techniques for direct polymer analysis. Full article

(This article belongs to the Special Issue Food Packaging Materials)

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11 pages, 4907 KiB

Open AccessArticle

Organic Salts of p-Coumaric Acid and Trans-Ferulic Acid with Aminopicolines

by Sosthene Nyomba Kamanda and Ayesha Jacobs

Molecules 2020, 25(3), 751; https://doi.org/10.3390/molecules25030751 - 10 Feb 2020

Cited by 3 | Viewed by 3925

Abstract

p-Coumaric acid (pCA) and trans-ferulic acid (TFA) were co-crystallised with 2-amino-4-picoline (2A4MP) and 2-amino-6-picoline (2A6MP) producing organic salts of (pCA⁻)(2A4MP⁺) (1), (pCA^̶ )(2A6MP⁺) (2) [...] Read more.

p-Coumaric acid (pCA) and trans-ferulic acid (TFA) were co-crystallised with 2-amino-4-picoline (2A4MP) and 2-amino-6-picoline (2A6MP) producing organic salts of (pCA⁻)(2A4MP⁺) (1), (pCA^̶ )(2A6MP⁺) (2) and (TFA^̶ )(2A4MP⁺)·(

\frac{3}{2}

H₂O) (3). For salt 3, water was included in the crystal structure fulfilling a bridging role. pCA formed a 1:1 salt with 2A4MP (Z’ = 1) and a 4:4 salt with 2A6MP (Z’ = 4). The thermal stability of the salts was determined using differential scanning calorimetry (DSC). Salt 2 had the highest thermal stability followed by salt 1 and salt 3. The salts were also characterised using Fourier transform infrared (FTIR) spectroscopy. Hirshfeld surface analysis was used to study the different intermolecular interactions in the three salts. Solvent-assisted grinding was also investigated in attempts to reproduce the salts. Full article

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28 pages, 870 KiB

Open AccessFeature PaperArticle

Assessment of the Quality of Polluted Areas in Northwest Romania Based on the Content of Elements in Different Organs of Grapevine (Vitis vinifera L.)

by Florin Dumitru Bora, Claudiu Ioan Bunea, Romeo Chira and Andrea Bunea

Molecules 2020, 25(3), 750; https://doi.org/10.3390/molecules25030750 - 9 Feb 2020

Cited by 23 | Viewed by 3938

Abstract

The purpose of this study was to evaluate the environmental quality of polluted areas near the Baia Mare Mining and Smelting Complex for future improvements the quality of the environment in polluted areas, such as the city of Baia Mare and its surroundings. [...] Read more.

The purpose of this study was to evaluate the environmental quality of polluted areas near the Baia Mare Mining and Smelting Complex for future improvements the quality of the environment in polluted areas, such as the city of Baia Mare and its surroundings. Samples of soil and organs of grapevine (Vitis vinifera L.) were collected from Baia Mare, Baia Sprie and surrounding areas (Simleul Silvaniei) and their content of Cu, Zn, Pb, Cd, Ni, Co, As, Cr, Hg were analyzed. Most soil and plant samples showed higher metal concentrations in Baia Mare and Baia Sprie areas compared to Simleul Silvaniei, exceeding the normal values. The results obtained from the translocation factors, mobility ratio, as well as from Pearson correlation study confirmed that very useful information is recorded in plant organs: root, canes, leaves and fruit. Results also indicated that Vitis vinifera L. has some highly effective strategies to tolerate heavy metal-induced stress, may also be useful as a vegetation protection barrier from considerable atmospheric pollution. At the same time, berries are safe for consumption to a large degree, which is a great advantage of this species. Full article

(This article belongs to the Special Issue Analytical Methods for Toxics Determination)

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14 pages, 697 KiB

Open AccessReview

Health Properties and Composition of Honeysuckle Berry Lonicera caerulea L. An Update on Recent Studies

by Marta Gołba, Anna Sokół-Łętowska and Alicja Z. Kucharska

Molecules 2020, 25(3), 749; https://doi.org/10.3390/molecules25030749 - 9 Feb 2020

Cited by 82 | Viewed by 9090

Abstract

Lonicera caerulea L., also known as haskap or honeysuckle berry, is a fruit commonly planted in eastern Europe, Canada and Asia. The fruit was registered as a traditional food from a third country under European Union regulations only on December 2018. It is [...] Read more.

Lonicera caerulea L., also known as haskap or honeysuckle berry, is a fruit commonly planted in eastern Europe, Canada and Asia. The fruit was registered as a traditional food from a third country under European Union regulations only on December 2018. It is resistant to cold, pests, various soil acidities and diseases. However, its attractiveness is associated mostly with its health properties. The fruit shows anticancer, anti-inflammatory, and antioxidant activity—important factors in improving health. These features result from the diverse content of phytochemicals in honeysuckle berries with high concentrations of phytocompounds, mainly hydroxycinnamic acids, hydroxybenzoic acids, flavanols, flavones, isoflavones, flavonols, flavanones and anthocyanins but also iridoids, present in the fruit in exceptional amounts. The content and health properties of the fruit were identified to be dependent on cultivar, genotype and the place of harvesting. Great potential benefits of this nutritious food are its ability to minimize the negative effects of UV radiation, diabetes mellitus and neurodegenerative diseases, and to exert hepato- and cardioprotective activity. Full article

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15 pages, 2390 KiB

Open AccessReview

Recent Advances in Copper Catalyzed Alcohol Oxidation in Homogeneous Medium

by Telma F. S. Silva and Luísa M. D. R. S. Martins

Molecules 2020, 25(3), 748; https://doi.org/10.3390/molecules25030748 - 9 Feb 2020

Cited by 59 | Viewed by 8644

Abstract

The development of sustainable processes and products through innovative catalytic materials and procedures that allow a better use of resources is undoubtedly one of the most significant issues facing researchers nowadays. Environmental and economically advanced catalytic processes for selective oxidation of alcohols are [...] Read more.

The development of sustainable processes and products through innovative catalytic materials and procedures that allow a better use of resources is undoubtedly one of the most significant issues facing researchers nowadays. Environmental and economically advanced catalytic processes for selective oxidation of alcohols are currently focused on designing new catalysts able to activate green oxidants (dioxygen or peroxides) and applying unconventional conditions of sustainable significance, like the use of microwave irradiation as an alternative energy source. This short review aims to provide an overview of the recently (2015–2020) discovered homogeneous aerobic and peroxidative oxidations of primary and secondary alcohols catalyzed by copper complexes, highlighting new catalysts with potential application in sustainable organic synthesis, with significance in academia and industry. Full article

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13 pages, 5662 KiB

Open AccessArticle

Selection of Aptamers Specific for DEHP Based on ssDNA Library Immobilized SELEX and Development of Electrochemical Impedance Spectroscopy Aptasensor

by Qi Lu, Xixia Liu, Jianjun Hou, Qiuxue Yuan, Yani Li and Sirui Chen

Molecules 2020, 25(3), 747; https://doi.org/10.3390/molecules25030747 - 9 Feb 2020

Cited by 32 | Viewed by 5137

Abstract

A selection of aptamers specific for di(2-ethylhexyl) phthalate (DEHP) and development of electrochemical impedance spectroscopy (EIS) aptasensor are described in this paper. The aptamers were selected from an immobilized ssDNA library using the systematic evolution of ligands by exponential enrichment (SELEX). The enrichment [...] Read more.

A selection of aptamers specific for di(2-ethylhexyl) phthalate (DEHP) and development of electrochemical impedance spectroscopy (EIS) aptasensor are described in this paper. The aptamers were selected from an immobilized ssDNA library using the systematic evolution of ligands by exponential enrichment (SELEX). The enrichment was monitored using real-time quantitative PCR (Q-PCR), and the aptamers were identified by high-throughput sequencing (HTS), gold nanoparticles (AuNPs) colorimetric assay, and localized surface plasmon resonance (LSPR). The EIS aptasensor was developed to detect DEHP in water samples. After eight rounds of enrichment, HTS, AuNPs colorimetric assay, and LSPR analysis indicated that four aptamers had higher binding activity, and aptamer 31 had the highest affinity (Kd = 2.26 ± 0.06 nM). The EIS aptasensor had a limit of detection (LOD) of 0.103 pg/mL with no cross-reactivity to DEHP analogs and a mean recovery of 76.07% to 141.32% for detection of DEHP in water samples. This aptamer is novel with the highest affinity and sensitivity. Full article

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20 pages, 3764 KiB

Open AccessArticle

A Novel Dimeric Exoglucanase (GH5_38): Biochemical and Structural Characterisation towards its Application in Alkyl Cellobioside Synthesis

by Mpho S. Mafa, Heinrich W. Dirr, Samkelo Malgas, Rui W. M. Krause, Konanani Rashamuse and Brett I. Pletschke

Molecules 2020, 25(3), 746; https://doi.org/10.3390/molecules25030746 - 9 Feb 2020

Cited by 6 | Viewed by 4190

Abstract

An exoglucanase (Exg-D) from the glycoside hydrolase family 5 subfamily 38 (GH5_38) was heterologously expressed and structurally and biochemically characterised at a molecular level for its application in alkyl glycoside synthesis. The purified Exg-D existed in both dimeric and monomeric forms in solution, [...] Read more.

An exoglucanase (Exg-D) from the glycoside hydrolase family 5 subfamily 38 (GH5_38) was heterologously expressed and structurally and biochemically characterised at a molecular level for its application in alkyl glycoside synthesis. The purified Exg-D existed in both dimeric and monomeric forms in solution, which showed highest activity on mixed-linked β-glucan (88.0 and 86.7 U/mg protein, respectively) and lichenin (24.5 and 23.7 U/mg protein, respectively). They displayed a broad optimum pH range from 5.5 to 7 and a temperature optimum from 40 to 60 °C. Kinetic studies demonstrated that Exg-D had a higher affinity towards β-glucan, with a K_m of 7.9 mg/mL and a k_cat of 117.2 s⁻¹, compared to lichenin which had a K_m of 21.5 mg/mL and a k_cat of 70.0 s⁻¹. The circular dichroism profile of Exg-D showed that its secondary structure consisted of 11% α-helices, 36% β-strands and 53% coils. Exg-D performed transglycosylation using p-nitrophenyl cellobioside as a glycosyl donor and several primary alcohols as acceptors to produce methyl-, ethyl- and propyl-cellobiosides. These products were identified and quantified via thin-layer chromatography (TLC) and liquid chromatography–mass spectrometry (LC-MS). We concluded that Exg-D is a novel and promising oligomeric glycoside hydrolase for the one-step synthesis of alkyl glycosides with more than one monosaccharide unit. Full article

(This article belongs to the Special Issue Green Compounds from Bio-Sources: Characterizations, Innovative Productions and Advanced Technological Applications)

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13 pages, 3300 KiB

Open AccessFeature PaperReview

The Pharmaceutical Industry in 2019. An Analysis of FDA Drug Approvals from the Perspective of Molecules

by Beatriz G. de la Torre and Fernando Albericio

Molecules 2020, 25(3), 745; https://doi.org/10.3390/molecules25030745 - 9 Feb 2020

Cited by 140 | Viewed by 14933

Abstract

During 2019, the US Food and Drug Administration (FDA) approved 48 new drugs (38 New Chemical Entities and 10 Biologics). Although this figure is slightly lower than that registered in 2018 (59 divided between 42 New Chemical Entities and 17 Biologics), a year [...] Read more.

During 2019, the US Food and Drug Administration (FDA) approved 48 new drugs (38 New Chemical Entities and 10 Biologics). Although this figure is slightly lower than that registered in 2018 (59 divided between 42 New Chemical Entities and 17 Biologics), a year that broke a record with respect to new drugs approved by this agency, it builds on the trend initiated in 2017, when 46 drugs were approved. Of note, three antibody drug conjugates, three peptides, and two oligonucleotides were approved in 2019. This report analyzes the 48 new drugs of the class of 2019 from a strictly chemical perspective. The classification, which was carried out on the basis of chemical structure, includes the following: Biologics (antibody drug conjugates, antibodies, and proteins); TIDES (peptide and oligonucleotides); drug combinations; natural products; and small molecules. Full article

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14 pages, 2476 KiB

Open AccessArticle

Identification and Characterization of Nematicidal Volatile Organic Compounds from Deep-Sea Virgibacillus dokdonensis MCCC 1A00493

by Dian Huang, Chen Yu, Zongze Shao, Minmin Cai, Guangyu Li, Longyu Zheng, Ziniu Yu and Jibin Zhang

Molecules 2020, 25(3), 744; https://doi.org/10.3390/molecules25030744 - 9 Feb 2020

Cited by 40 | Viewed by 4664

Abstract

Root-knot nematode diseases cause severe yield and economic losses each year in global agricultural production. Virgibacillus dokdonensis MCCC 1A00493, a deep-sea bacterium, shows a significant nematicidal activity against Meloidogyne incognita in vitro. However, information about the active substances of V. dokdonensis MCCC 1A00493 [...] Read more.

Root-knot nematode diseases cause severe yield and economic losses each year in global agricultural production. Virgibacillus dokdonensis MCCC 1A00493, a deep-sea bacterium, shows a significant nematicidal activity against Meloidogyne incognita in vitro. However, information about the active substances of V. dokdonensis MCCC 1A00493 is limited. In this study, volatile organic compounds (VOCs) from V. dokdonensis MCCC 1A00493 were isolated and analyzed through solid-phase microextraction and gas chromatography–mass spectrometry. Four VOCs, namely, acetaldehyde, dimethyl disulfide, ethylbenzene, and 2-butanone, were identified, and their nematicidal activities were evaluated. The four VOCs had a variety of active modes on M. incognita juveniles. Acetaldehyde had direct contact killing, fumigation, and attraction activities; dimethyl disulfide had direct contact killing and attraction activities; ethylbenzene had an attraction activity; and 2-butanone had a repellent activity. Only acetaldehyde had a fumigant activity to inhibit egg hatching. Combining this fumigant activity against eggs and juveniles could be an effective strategy to control the different developmental stages of M. incognita. The combination of direct contact and attraction activities could also establish trapping and killing strategies against root-knot nematodes. Considering all nematicidal modes or strategies, we could use V. dokdonensis MCCC 1A00493 to set up an integrated strategy to control root-knot nematodes. Full article

(This article belongs to the Section Natural Products Chemistry)

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13 pages, 4297 KiB

Open AccessArticle

Temperature Effect on the Adsorption and Volumetric Properties of Aqueous Solutions of Kolliphor^®ELP

by Katarzyna Szymczyk, Magdalena Szaniawska and Joanna Krawczyk

Molecules 2020, 25(3), 743; https://doi.org/10.3390/molecules25030743 - 9 Feb 2020

Cited by 6 | Viewed by 4106

Abstract

Density, viscosity and surface tension of Kolliphor^® ELP, the nonionic surfactant aqueous solutions were measured at temperature T = 293–318 K and at 5K interval. Steady-state fluorescence measurements have been also made using pyrene as a probe. On the basis of the [...] Read more.

Density, viscosity and surface tension of Kolliphor^® ELP, the nonionic surfactant aqueous solutions were measured at temperature T = 293–318 K and at 5K interval. Steady-state fluorescence measurements have been also made using pyrene as a probe. On the basis of the obtained results, a number of thermodynamic, thermo-acoustic and anharmonic parameters of the studied surfactant have been evaluated and interpreted in terms of structural effects and solute–solvent interactions. The results suggest that the molecules of studied surfactant at concentrations higher than the critical micelle concentration act as structure makers of the water structure. Full article

(This article belongs to the Section Physical Chemistry)

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22 pages, 5337 KiB

Open AccessArticle

Sterically Stabilised Polymeric Mesoporous Silica Nanoparticles Improve Doxorubicin Efficiency: Tailored Cancer Therapy

by Thashini Moodley and Moganavelli Singh

Molecules 2020, 25(3), 742; https://doi.org/10.3390/molecules25030742 - 8 Feb 2020

Cited by 36 | Viewed by 5491

Abstract

The fruition, commercialisation and clinical application combining nano-engineering, nanomedicine and material science for utilisation in drug delivery is becoming a reality. The successful integration of nanomaterial in nanotherapeutics requires their critical development to ensure physiological and biological compatibility. Mesoporous silica nanoparticles (MSNs) are [...] Read more.

The fruition, commercialisation and clinical application combining nano-engineering, nanomedicine and material science for utilisation in drug delivery is becoming a reality. The successful integration of nanomaterial in nanotherapeutics requires their critical development to ensure physiological and biological compatibility. Mesoporous silica nanoparticles (MSNs) are attractive nanocarriers due to their biodegradable, biocompatible, and relative malleable porous frameworks that can be functionalized for enhanced targeting and delivery in a variety of disease models. The optimal formulation of an MSN with polyethylene glycol (2% and 5%) and chitosan was undertaken, to produce sterically stabilized, hydrophilic MSNs, capable of efficient loading and delivery of the hydrophobic anti-neoplastic drug, doxorubicin (DOX). The pH-sensitive release kinetics of DOX, together with the anticancer, apoptosis and cell-cycle activities of DOX-loaded MSNs in selected cancer cell lines were evaluated. MSNs of 36–60 nm in size, with a pore diameter of 9.8 nm, and a cumulative surface area of 710.36 m²/g were produced. The 2% pegylated MSN formulation (PCMSN) had the highest DOX loading capacity (0.98 mg_dox/mg_msn), and a sustained release profile over 72 h. Pegylated-drug nanoconjugates were effective at a concentration range between 20–50 μg/mL, inducing apoptosis in cancer cells, and affirming their potential as effective drug delivery vehicles. Full article

(This article belongs to the Special Issue Applications of Materials in Drug Delivery)

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20 pages, 2807 KiB

Open AccessArticle

Synthesis, Structural, and Cytotoxic Properties of New Water-Soluble Copper(II) Complexes Based on 2,9-Dimethyl-1,10-Phenanthroline and Their One Derivative Containing 1,3,5-Triaza-7-Phosphaadamantane-7-Oxide

by Ewelina I. Śliwa, Urszula Śliwińska-Hill, Barbara Bażanów, Miłosz Siczek, Julia Kłak and Piotr Smoleński

Molecules 2020, 25(3), 741; https://doi.org/10.3390/molecules25030741 - 8 Feb 2020

Cited by 15 | Viewed by 5386

Abstract

A series of water-soluble copper(II) complexes based on 2,9-dimethyl-1,10-phenanthroline (dmphen) and mixed-ligands, containing PTA=O (1,3,5-triaza-7-phosphaadamantane-7-oxide) have been synthesized and fully characterized. Two types of complexes have been obtained, monocationic [Cu(NO₃)(O-PTA=O)(dmphen)][PF₆] (1), [Cu(Cl)(dmphen)₂][PF₆] ( [...] Read more.

A series of water-soluble copper(II) complexes based on 2,9-dimethyl-1,10-phenanthroline (dmphen) and mixed-ligands, containing PTA=O (1,3,5-triaza-7-phosphaadamantane-7-oxide) have been synthesized and fully characterized. Two types of complexes have been obtained, monocationic [Cu(NO₃)(O-PTA=O)(dmphen)][PF₆] (1), [Cu(Cl)(dmphen)₂][PF₆] (2), and neutral [Cu(NO₃)₂(dmphen)] (3). The solid-state structures of all complexes have been determined by single-crystal X-ray diffraction. Magnetic studies for the complex 1–3 indicated a very weak antiferromagnetic interaction between copper(II) ions in crystal lattice. Complexes were successfully evaluated for their cytotoxic activities on the normal human dermal fibroblast (NHDF) cell line and the antitumor activity using the human lung carcinoma (A549), epithelioid cervix carcinoma (HeLa), colon (LoVo), and breast adenocarcinoma (MCF-7) cell lines. Complexes 1 and 3 revealed lower toxicity to NHDF than A549 and HeLa cells, meanwhile compound 2 appeared to be more toxic to NHDF cell line in comparison to all cancer lines. Additionally, interactions between the complexes and human apo-transferrin (apo-Tf) using fluorescence and circular dichroism (CD) spectroscopy were also investigated. All compounds interacted with apo-transferrin, causing same changes of the protein conformation. Electrostatic interactions dominate in the 1/2 – apo- Tf systems and hydrophobic and ionic interactions in the case of 3. Full article

(This article belongs to the Special Issue Bipyridines: Synthesis, Functionalization and Applications)

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15 pages, 7672 KiB

Open AccessArticle

Ultrasound and Radiation-Induced Catalytic Oxidation of 1-Phenylethanol to Acetophenone with Iron-Containing Particulate Catalysts

by Mohamed M. A. Soliman, Maximilian N. Kopylovich, Elisabete C. B. A. Alegria, Ana P. C. Ribeiro, Ana M. Ferraria, Ana M. Botelho do Rego, Luís M. M. Correia, Marta S. Saraiva and Armando J. L. Pombeiro

Molecules 2020, 25(3), 740; https://doi.org/10.3390/molecules25030740 - 8 Feb 2020

Cited by 7 | Viewed by 4588

Abstract

Iron-containing particulate catalysts of 0.1–1 µm size were prepared by wet and ball-milling procedures from common salts and characterized by FTIR, TGA, UV-Vis, PXRD, FEG-SEM, and XPS analyses. It was found that when the wet method was used, semi-spherical magnetic nanoparticles were formed, [...] Read more.

Iron-containing particulate catalysts of 0.1–1 µm size were prepared by wet and ball-milling procedures from common salts and characterized by FTIR, TGA, UV-Vis, PXRD, FEG-SEM, and XPS analyses. It was found that when the wet method was used, semi-spherical magnetic nanoparticles were formed, whereas the mechanochemical method resulted in the formation of nonmagnetic microscale needles and rectangles. Catalytic activity of the prepared materials in the oxidation of 1-phenylethanol to acetophenone was assessed under conventional heating, microwave (MW) irradiation, ultrasound (US), and oscillating magnetic field of high frequency (induction heating). In general, the catalysts obtained by wet methods exhibit lower activities, whereas the materials prepared by ball milling afford better acetophenone yields (up to 83%). A significant increase in yield (up to 4 times) was observed under the induction heating if compared to conventional heating. The study demonstrated that MW, US irradiations, and induction heating may have great potential as alternative ways to activate the catalytic system for alcohol oxidation. The possibility of the synthesized material to be magnetically recoverable has been also verified. Full article

(This article belongs to the Special Issue Mechanically Responsive Materials and Their Applications)

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20 pages, 3259 KiB

Open AccessArticle

Towards an Understanding of the Mode of Action of Human Aromatase Activity for Azoles through Quantum Chemical Descriptors-Based Regression and Structure Activity Relationship Modeling Analysis

by Chayawan Chayawan, Cosimo Toma, Emilio Benfenati and Ana Y. Caballero Alfonso

Molecules 2020, 25(3), 739; https://doi.org/10.3390/molecules25030739 - 8 Feb 2020

Cited by 9 | Viewed by 5868

Abstract

Aromatase is an enzyme member of the cytochrome P450 superfamily coded by the CYP19A1 gene. Its main action is the conversion of androgens into estrogens, transforming androstenedione into estrone and testosterone into estradiol. This enzyme is present in several tissues and it has [...] Read more.

Aromatase is an enzyme member of the cytochrome P450 superfamily coded by the CYP19A1 gene. Its main action is the conversion of androgens into estrogens, transforming androstenedione into estrone and testosterone into estradiol. This enzyme is present in several tissues and it has a key role in the maintenance of the balance of androgens and estrogens, and therefore in the regulation of the endocrine system. With regard to chemical safety and human health, azoles, which are used as agrochemicals and pharmaceuticals, are potential endocrine disruptors due to their agonist or antagonist interactions with the human aromatase enzyme. This theoretical study investigated the active agonist and antagonist properties of “chemical classes of azoles” to determine the relationships of azole interaction with CYP19A1, using stereochemical and electronic properties of the molecules through classification and multilinear regression (MLR) modeling. The antagonist activities for the same substituent on diazoles and triazoles vary with its chemical composition and its position and both heterocyclic systems require aromatic substituents. The triazoles require the spherical shape and diazoles have to be in proper proportion of the branching index and the number of ring systems for the inhibition. Considering the electronic aspects, triazole antagonist activity depends on the electrophilicity index that originates from interelectronic exchange interaction (ω_HF) and the LUMO energy (

E_{LUMO}^{PM 7}

), and the diazole antagonist activity originates from the penultimate orbital (

E_{HOMONL}^{PM 7}

) of diazoles. The regression models for agonist activity show that it is opposed by the static charges but favored by the delocalized charges on the diazoles and thiazoles. This study proposes that the electron penetration of azoles toward heme group decides the binding behavior and stereochemistry requirement for antagonist activity against CYP19A1 enzyme. Full article

(This article belongs to the Special Issue Integrated QSAR)

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16 pages, 1174 KiB

Open AccessReview

Current Approaches to and Future Perspectives on Methomyl Degradation in Contaminated Soil/Water Environments

by Ziqiu Lin, Wenping Zhang, Shimei Pang, Yaohua Huang, Sandhya Mishra, Pankaj Bhatt and Shaohua Chen

Molecules 2020, 25(3), 738; https://doi.org/10.3390/molecules25030738 - 8 Feb 2020

Cited by 66 | Viewed by 8174

Abstract

Methomyl is a broad-spectrum oxime carbamate commonly used to control arthropods, nematodes, flies, and crop pests. However, extensive use of this pesticide in agricultural practices has led to environmental toxicity and human health issues. Oxidation, incineration, adsorption, and microbial degradation methods have been [...] Read more.

Methomyl is a broad-spectrum oxime carbamate commonly used to control arthropods, nematodes, flies, and crop pests. However, extensive use of this pesticide in agricultural practices has led to environmental toxicity and human health issues. Oxidation, incineration, adsorption, and microbial degradation methods have been developed to remove insecticidal residues from soil/water environments. Compared with physicochemical methods, biodegradation is considered to be a cost-effective and ecofriendly approach to the removal of pesticide residues. Therefore, micro-organisms have become a key component of the degradation and detoxification of methomyl through catabolic pathways and genetic determinants. Several species of methomyl-degrading bacteria have been isolated and characterized, including Paracoccus, Pseudomonas, Aminobacter, Flavobacterium, Alcaligenes, Bacillus, Serratia, Novosphingobium, and Trametes. The degradation pathways of methomyl and the fate of several metabolites have been investigated. Further in-depth studies based on molecular biology and genetics are needed to elaborate their role in the evolution of novel catabolic pathways and the microbial degradation of methomyl. In this review, we highlight the mechanism of microbial degradation of methomyl along with metabolic pathways and genes/enzymes of different genera. Full article

(This article belongs to the Special Issue Biodegradation of Conventional and Emerging Pollutants)

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20 pages, 4197 KiB

Open AccessFeature PaperReview

Spider Silk for Tissue Engineering Applications

by Sahar Salehi, Kim Koeck and Thomas Scheibel

Molecules 2020, 25(3), 737; https://doi.org/10.3390/molecules25030737 - 8 Feb 2020

Cited by 168 | Viewed by 23000

Abstract

Due to its properties, such as biodegradability, low density, excellent biocompatibility and unique mechanics, spider silk has been used as a natural biomaterial for a myriad of applications. First clinical applications of spider silk as suture material go back to the 18th century. [...] Read more.

Due to its properties, such as biodegradability, low density, excellent biocompatibility and unique mechanics, spider silk has been used as a natural biomaterial for a myriad of applications. First clinical applications of spider silk as suture material go back to the 18th century. Nowadays, since natural production using spiders is limited due to problems with farming spiders, recombinant production of spider silk proteins seems to be the best way to produce material in sufficient quantities. The availability of recombinantly produced spider silk proteins, as well as their good processability has opened the path towards modern biomedical applications. Here, we highlight the research on spider silk-based materials in the field of tissue engineering and summarize various two-dimensional (2D) and three-dimensional (3D) scaffolds made of spider silk. Finally, different applications of spider silk-based materials are reviewed in the field of tissue engineering in vitro and in vivo. Full article

(This article belongs to the Special Issue Silk Fibroin Materials)

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18 pages, 4445 KiB

Open AccessArticle

Smart, Tunable CQDs with Antioxidant Properties for Biomedical Applications—Ecofriendly Synthesis and Characterization

by Łukasz Janus, Julia Radwan-Pragłowska, Marek Piątkowski and Dariusz Bogdał

Molecules 2020, 25(3), 736; https://doi.org/10.3390/molecules25030736 - 8 Feb 2020

Cited by 33 | Viewed by 4630

Abstract

Carbon quantum dots (CQDs) are nanoobjects of a size below 10 nm. Due to their favorable features, such as tunable luminescence, unique optical properties, water solubility, and lack of cytotoxicity, they are willingly applied in biomedicine. They can be obtained via bottom-up and [...] Read more.

Carbon quantum dots (CQDs) are nanoobjects of a size below 10 nm. Due to their favorable features, such as tunable luminescence, unique optical properties, water solubility, and lack of cytotoxicity, they are willingly applied in biomedicine. They can be obtained via bottom-up and top-down methods. However, to increase their quantum yield they must undergo post-processing. The aim of the following research was to obtain a new type of CQDs modified with a rhodamine b derivative to enhance their fluorescence performance without biocompability deterioration. For their preparation glucose was used as a precursor and four different carbonizing agents which affected semi- and final products luminescence properties. The ready nanomaterials were investigated over their chemical structure by FTIR and NMR, whereas morphology was investigated by the TEM method. Their optical properties were determined by UV–VIS spectroscopy. Fluorescence behavior, photo- and pH-stability, as well as solvatochromism showed their applicability in various biomedical applications due to the controlled properties. The samples exhibited excellent antioxidant activity and lack of cytotoxicity on L929 mouse fibroblasts. The results showed that proposed strategy enables preparation of the superior nanomaterials with outstanding luminescence properties such as quantum yield up to 17% which can be successfully applied in cell labelling, bioimaging, and theranostics. Full article

(This article belongs to the Special Issue Carbon Dots—Promising Nanomaterials)

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21 pages, 1115 KiB

Open AccessReview

Peptide Nucleic Acids and Gene Editing: Perspectives on Structure and Repair

by Nicholas G. Economos, Stanley Oyaghire, Elias Quijano, Adele S. Ricciardi, W. Mark Saltzman and Peter M. Glazer

Molecules 2020, 25(3), 735; https://doi.org/10.3390/molecules25030735 - 8 Feb 2020

Cited by 49 | Viewed by 9125

Abstract

Unusual nucleic acid structures are salient triggers of endogenous repair and can occur in sequence-specific contexts. Peptide nucleic acids (PNAs) rely on these principles to achieve non-enzymatic gene editing. By forming high-affinity heterotriplex structures within the genome, PNAs have been used to correct [...] Read more.

Unusual nucleic acid structures are salient triggers of endogenous repair and can occur in sequence-specific contexts. Peptide nucleic acids (PNAs) rely on these principles to achieve non-enzymatic gene editing. By forming high-affinity heterotriplex structures within the genome, PNAs have been used to correct multiple human disease-relevant mutations with low off-target effects. Advances in molecular design, chemical modification, and delivery have enabled systemic in vivo application of PNAs resulting in detectable editing in preclinical mouse models. In a model of β-thalassemia, treated animals demonstrated clinically relevant protein restoration and disease phenotype amelioration, suggesting a potential for curative therapeutic application of PNAs to monogenic disorders. This review discusses the rationale and advances of PNA technologies and their application to gene editing with an emphasis on structural biochemistry and repair. Full article

(This article belongs to the Special Issue Peptide Nucleic Acids: Applications in Biomedical Sciences)

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