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Molecules, Volume 20, Issue 3 (March 2015), Pages 3496-5259

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Open AccessArticle Bacillus toyonensis Strain AEMREG6, a Bacterium Isolated from South African Marine Environment Sediment Samples Produces a Glycoprotein Bioflocculant
Molecules 2015, 20(3), 5239-5259; https://doi.org/10.3390/molecules20035239
Received: 26 February 2015 / Revised: 15 March 2015 / Accepted: 17 March 2015 / Published: 23 March 2015
Cited by 17 | PDF Full-text (1720 KB) | HTML Full-text | XML Full-text
Abstract
A bioflocculant-producing bacteria, isolated from sediment samples of a marine environment in the Eastern Cape Province of South Africa demonstrated a flocculating activity above 60% for kaolin clay suspension. Analysis of the 16S ribosomal deoxyribonucleic acid (rDNA) nucleotide sequence of the isolate in
[...] Read more.
A bioflocculant-producing bacteria, isolated from sediment samples of a marine environment in the Eastern Cape Province of South Africa demonstrated a flocculating activity above 60% for kaolin clay suspension. Analysis of the 16S ribosomal deoxyribonucleic acid (rDNA) nucleotide sequence of the isolate in the GenBank database showed 99% similarity to Bacillus toyonensis strain BCT-7112 and it was deposited in the GenBank as Bacillus toyonensis strain AEMREG6 with accession number KP406731. The bacteria produced a bioflocculant (REG-6) optimally in the presence of glucose and NH4NO3 as the sole carbon and nitrogen source, respectively, initial medium pH of 5 and Ca2+ as the cation of choice. Chemical analysis showed that purified REG-6 was a glycoprotein mainly composed of polysaccharide (77.8%) and protein (11.5%). It was thermally stable and had strong flocculating activity against kaolin suspension over a wide range of pH values (3–11) with a relatively low dosage requirement of 0.1 mg/mL in the presence of Mn2+. Fourier transform infrared spectroscopy (FTIR) revealed the presence of hydroxyl, carboxyl and amide groups preferred for flocculation. Scanning electron microscopy (SEM) revealed that bridging was the main flocculation mechanism of REG-6. The outstanding flocculating performance of REG-6 holds great potential to replace the hazardous chemical flocculants currently used in water treatment. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Effect of Pulsed Electric Fields on the Flavour Profile of Red-Fleshed Sweet Cherries (Prunus avium var. Stella)
Molecules 2015, 20(3), 5223-5238; https://doi.org/10.3390/molecules20035223
Received: 25 November 2014 / Revised: 25 February 2015 / Accepted: 10 March 2015 / Published: 23 March 2015
Cited by 4 | PDF Full-text (1000 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this research was to study the effect of pulsed electric fields (PEF) on the flavour profile of red-fleshed sweet cherries (Prunus avium variety Stella). The cherry samples were treated at a constant pulse frequency of 100 Hz, a constant
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The aim of this research was to study the effect of pulsed electric fields (PEF) on the flavour profile of red-fleshed sweet cherries (Prunus avium variety Stella). The cherry samples were treated at a constant pulse frequency of 100 Hz, a constant pulse width of 20 μs, different electric field strengths between 0.3 and 2.5 kV/cm and specific energy ranging from 31 to 55 kJ/kg. Volatile compounds of samples were analysed using an automated headspace solid phase microextraction (HS–SPME) method coupled with gas chromatography-mass spectrometry (GC–MS). A total of 33 volatile compounds were identified with benzaldehyde, hexanal, (E)-2-hexenal, (Z)-2-hexen-1-ol, and benzyl alcohol being the predominant volatiles in different PEF-treated samples. Aldehydes namely butanal, octanal, 2-octenal, and nonanal, and (Z)-2-hexen-1-ol increased significantly 24 h after PEF treatment at electric field strengths of more than 1.0 kV/cm. Samples incubated for 24 h after PEF treatment (S3) generated higher concentrations of volatiles than samples immediately after PEF treatments (S2). Quantitative results revealed that more flavour volatiles were released and associated with S3 samples after 24 h storage and S2 samples immediately after PEF both with the highest electric field intensities. Interestingly, this study found that the PEF treatments at the applied electric field strength and energy did not result in releasing/producing undesirable flavour compounds. Full article
(This article belongs to the Special Issue Aromas and Volatiles of Fruits)
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Open AccessArticle iso-Petromyroxols: Novel Dihydroxylated Tetrahydrofuran Enantiomers from Sea Lamprey (Petromyzon marinus)
Molecules 2015, 20(3), 5215-5222; https://doi.org/10.3390/molecules20035215
Received: 17 February 2015 / Revised: 17 March 2015 / Accepted: 18 March 2015 / Published: 23 March 2015
Cited by 4 | PDF Full-text (959 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
An enantiomeric pair of new fatty acid-derived hydroxylated tetrahydrofurans, here named iso-petromyroxols, were isolated from sea lamprey larvae-conditioned water. The relative configuration of iso-petromyroxol was elucidated with 1D and 2D NMR spectroscopic analyses. The ratio of enantiomers (er) in
[...] Read more.
An enantiomeric pair of new fatty acid-derived hydroxylated tetrahydrofurans, here named iso-petromyroxols, were isolated from sea lamprey larvae-conditioned water. The relative configuration of iso-petromyroxol was elucidated with 1D and 2D NMR spectroscopic analyses. The ratio of enantiomers (er) in the natural sample was measured by chiral-HPLC-MS/MS to be ca. 3:1 of (–)- to (+)-antipodes. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Selective C-Arylation of 2,5-Dibromo-3-hexylthiophene via Suzuki Cross Coupling Reaction and Their Pharmacological Aspects
Molecules 2015, 20(3), 5202-5214; https://doi.org/10.3390/molecules20035202
Received: 4 December 2014 / Revised: 6 February 2015 / Accepted: 16 February 2015 / Published: 23 March 2015
Cited by 5 | PDF Full-text (865 KB) | HTML Full-text | XML Full-text
Abstract
The present study reports the synthesis of various new derivatives based on 5-aryl-2-bromo-3-hexylthiophene with moderate-to-good yields via a palladium-catalyzed Suzuki cross-coupling reaction. This coupling method involved the reaction of 2,5-dibromo-3-hexylthiophene with several arylboronic acids in order to synthesize corresponding thiophene derivatives under controlled
[...] Read more.
The present study reports the synthesis of various new derivatives based on 5-aryl-2-bromo-3-hexylthiophene with moderate-to-good yields via a palladium-catalyzed Suzuki cross-coupling reaction. This coupling method involved the reaction of 2,5-dibromo-3-hexylthiophene with several arylboronic acids in order to synthesize corresponding thiophene derivatives under controlled and optimal reaction conditions. The different substituents (CH3, OCH3, Cl, F etc.) present on arylboronic acids are found to have significant electronic effects on the overall properties of new products. The synthesized thiophene molecules were studied for their haemolytic, biofilm inhibition and anti-thrombolytic activities, and almost all products showed potentially good properties. The compound 2-bromo-5-(3-chloro-4-fluorophenyl)-3-hexylthiophenein particular exhibited the highest values for haemolytic and bio-film inhibition activities among all newly synthesized derivatives. In addition, the compound 2-bromo-3-hexyl-5-(4-iodophenyl)thiophene also showed high anti-thrombolytic activity, suggesting the potential medicinal applications of these newly synthesized compounds. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Syntheses of Nickel (II) Complexes from Novel Semicarbazone Ligands with Chloroformylarylhydrazine, Benzimidazole and Salicylaldehyde Moieties
Molecules 2015, 20(3), 5184-5201; https://doi.org/10.3390/molecules20035184
Received: 30 January 2015 / Revised: 11 March 2015 / Accepted: 13 March 2015 / Published: 20 March 2015
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Abstract
This study addressed the design and syntheses of diverse ligands, which were then successfully treated with Ni (II) ion to afford a series of nickel complexes. α-Chloroformylarylhydrazine hydrochlorides 6 contain two different functional groups. One is a strong nucleophile, and the other is
[...] Read more.
This study addressed the design and syntheses of diverse ligands, which were then successfully treated with Ni (II) ion to afford a series of nickel complexes. α-Chloroformylarylhydrazine hydrochlorides 6 contain two different functional groups. One is a strong nucleophile, and the other is a good electrophile. Therefore, it can be designed to react with several reagents to obtain diverse derivatives which can be used as ligands for metal complexes. Furthermore, benzimidazole and salicylaldehyde can provide electron donor sites, N and O electron donors, separately. Hence, the starting materials α-chloroformylarylhydrazine hydrochlorides 6 were first treated with 2-(aminomethyl)-benzimidazole (7) to give the corresponding semicarbazides 8. Then, the semicarbazides 8 reacted with various substituted salicylaldehydes 911 to afford the desired substituted-salicylaldehyde 2-aryl-4-substituted semicarbazones 1214, which could coordinate with nickel (II) ion to give the corresponding nickel complexes 1517. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Influence of Pea Protein Aggregates on the Structure and Stability of Pea Protein/Soybean Polysaccharide Complex Emulsions
Molecules 2015, 20(3), 5165-5183; https://doi.org/10.3390/molecules20035165
Received: 28 November 2014 / Revised: 14 March 2015 / Accepted: 16 March 2015 / Published: 20 March 2015
Cited by 9 | PDF Full-text (2473 KB) | HTML Full-text | XML Full-text
Abstract
The applications of plant proteins in the food and beverage industry have been hampered by their precipitation in acidic solution. In this study, pea protein isolate (PPI) with poor dispersibility in acidic solution was used to form complexes with soybean soluble polysaccharide (SSPS),
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The applications of plant proteins in the food and beverage industry have been hampered by their precipitation in acidic solution. In this study, pea protein isolate (PPI) with poor dispersibility in acidic solution was used to form complexes with soybean soluble polysaccharide (SSPS), and the effects of PPI aggregates on the structure and stability of PPI/SSPS complex emulsions were investigated. Under acidic conditions, high pressure homogenization disrupts the PPI aggregates and the electrostatic attraction between PPI and SSPS facilitates the formation of dispersible PPI/SSPS complexes. The PPI/SSPS complex emulsions prepared from the PPI containing aggregates prove to possess similar droplet structure and similar stability compared with the PPI/SSPS emulsions produced from the PPI in which the aggregates have been previously removed by centrifugation. The oil droplets are protected by PPI/SSPS complex interfacial films and SSPS surfaces. The emulsions show long-term stability against pH and NaCl concentration changes. This study demonstrates that PPI aggregates can also be used to produce stable complex emulsions, which may promote the applications of plant proteins in the food and beverage industry. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Reduction of False Positives in Structure-Based Virtual Screening When Receptor Plasticity Is Considered
Molecules 2015, 20(3), 5152-5164; https://doi.org/10.3390/molecules20035152
Received: 5 February 2015 / Revised: 9 March 2015 / Accepted: 16 March 2015 / Published: 19 March 2015
Cited by 7 | PDF Full-text (2414 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Structure-based virtual screening for selecting potential drug candidates is usually challenged by how numerous false positives in a molecule library are excluded when receptor plasticity is considered. In this study, based on the binding energy landscape theory, a hypothesis that a true inhibitor
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Structure-based virtual screening for selecting potential drug candidates is usually challenged by how numerous false positives in a molecule library are excluded when receptor plasticity is considered. In this study, based on the binding energy landscape theory, a hypothesis that a true inhibitor can bind to different conformations of the binding site favorably was put forth, and related strategies to defeat this challenge were devised; reducing false positives when receptor plasticity is considered. The receptor in the study is the influenza A nucleoprotein, whose oligomerization is a requirement for RNA binding. The structural flexibility of influenza A nucleoprotein was explored by molecular dynamics simulations. The resultant distinctive structures and the crystal structure were used as receptor models in docking exercises in which two binding sites, the tail-loop binding pocket and the RNA binding site, were targeted with the Otava PrimScreen1 diversity-molecule library using the GOLD software. The intersection ligands that were listed in the top-ranked molecules from all receptor models were selected. Such selection strategy successfully distinguished high-affinity and low-affinity control molecules added to the molecule library. This work provides an applicable approach for reducing false positives and selecting true ligands from molecule libraries. Full article
(This article belongs to the Special Issue Molecular Docking in Drug Design)
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Open AccessArticle Antiviral Activity of a Nanoemulsion of Polyprenols from Ginkgo Leaves against Influenza A H3N2 and Hepatitis B Virus in Vitro
Molecules 2015, 20(3), 5137-5151; https://doi.org/10.3390/molecules20035137
Received: 4 December 2014 / Revised: 2 March 2015 / Accepted: 10 March 2015 / Published: 19 March 2015
Cited by 2 | PDF Full-text (2204 KB) | HTML Full-text | XML Full-text
Abstract
In order to improve the bioavailability levels of polyprenols (derived from ginkgo leaves (GBP)) in the human body, a GBP nanoemulsion was prepared, and its antiviral activity was evaluated against influenza A H3N2 and hepatitis B virus in vitro. Methods: A GBP
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In order to improve the bioavailability levels of polyprenols (derived from ginkgo leaves (GBP)) in the human body, a GBP nanoemulsion was prepared, and its antiviral activity was evaluated against influenza A H3N2 and hepatitis B virus in vitro. Methods: A GBP nanoemulsion was prepared by inversed-phase emulsification (IPE). Next, we investigated the antiviral activity of the GBP nanoemulsion on influenza A H3N2 and hepatitis B virus in vitro by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenlytetrezolium bromide) method. ELISA and the fluorescent quantitative PCR method were used to measure the content of HBsAg, HBeAg and DNA virus in human samples. Results: The GBP nanoemulsion exhibited uniformity at an average particle size 97 nm with a hydrophilic-lipophilic balance (HLB) of 9.5. GBP is non-toxic to normal cells, hepatitis B virus DNA, hepatitis B virus antigen and HepG2215. Furthermore, GBP could reach a 70% virucidal activity and a 74.9% protection rate (*** p < 0.001) on MDCK cells infected with H3N2 virus at a high concentration of 100 μg/mL. GBP had a good inhibition rate on HBsAg (52.11%, ** p < 0.01) at 50 μg/mL and Day 9 of incubation, and a 67.32% inhibition effect on HBeAg at a high concentration of 100 μg/mL and Day 9. GBP had good inhibition on HBV DNA with CT 18.6 and lower copies (** p < 0.01) at a middle concentration of 12.5 to 25 μg/mL. Conclusions: The GBP nanoemulsion was very stable and non-toxic and had very strong antiviral activity against influenza A H3N2 and hepatitis B virus in vitro. The inhibitory effects and reactive mechanisms were similar to the drug, 3TC; by lengthening the incubation time and increasing the drug concentration, GBP has promising potential as an antiviral drug. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Functional Characterization of Individual- and Mixed-Burgundian Saccharomyces cerevisiae Isolates for Fermentation of Pinot Noir
Molecules 2015, 20(3), 5112-5136; https://doi.org/10.3390/molecules20035112
Received: 8 January 2015 / Revised: 25 February 2015 / Accepted: 9 March 2015 / Published: 19 March 2015
Cited by 2 | PDF Full-text (1872 KB) | HTML Full-text | XML Full-text
Abstract
Pinot noir has traditionally been fermented by native flora of multiple yeasts producing a complex combination of aromas and flavors. With the use of industrial dry yeasts, winemakers gained enological reliability and consistency in their wines, but lost diversity and complexity. This research
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Pinot noir has traditionally been fermented by native flora of multiple yeasts producing a complex combination of aromas and flavors. With the use of industrial dry yeasts, winemakers gained enological reliability and consistency in their wines, but lost diversity and complexity. This research evaluated the use of co-culturing yeasts to fulfill this dual role. Fermentations of Burgundian Saccharomyces cerevisiae isolates and their mixtures were evaluated for their enological characteristics and production of volatile compounds, at 22 °C and 27 °C. The novel isolates were genetically unique and enologically equivalent to the industrial strains. Analysis of variance and principal component analysis of 25 headspace volatiles revealed differences among the yeasts and between the fermentation temperatures. Wines from the mixed-Burgundian isolates were most similar to one another and could be differentiated from the industrial strains at both 22 °C and 27 °C. Mixed-Burgundian wines at both temperatures had higher concentrations of ethyl esters and acetate esters, compared to the industrial strains which had higher concentrations of higher alcohols at 27 °C and higher concentration of other ethyl esters at 22 °C. Given the unique profiles of the co-cultured wines, this research offers winemakers a strategy for producing wines with unique and more complex characters without the risk of spontaneous fermentations. Full article
(This article belongs to the collection Wine Chemistry)
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Open AccessArticle Docking and Antiherpetic Activity of 2-Aminobenzo[de]-isoquinoline-1,3-diones
Molecules 2015, 20(3), 5099-5111; https://doi.org/10.3390/molecules20035099
Received: 27 January 2015 / Accepted: 9 March 2015 / Published: 19 March 2015
Cited by 4 | PDF Full-text (1044 KB) | HTML Full-text | XML Full-text
Abstract
As part of our search for new compounds having antiviral effects, the prepared 2-aminonaphthalimide series was examined for its activity against the herpes simplex viruses HSV-1 and HSV-2. This represents the first study of the antiviral effects of this class of compounds. The
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As part of our search for new compounds having antiviral effects, the prepared 2-aminonaphthalimide series was examined for its activity against the herpes simplex viruses HSV-1 and HSV-2. This represents the first study of the antiviral effects of this class of compounds. The new series of 2-amino-1H-benzo[de]isoquinoline-1,3-diones was examined against HSV-1 and HSV-2 using a cytopathic effect inhibition assay. In terms of effective concentration (EC50), furaldehyde, thiophene aldehyde and allyl isothiocyanide derivatives 1416 showed potent activity against HSV-1 (EC50 = 19.6, 16.2 and 17.8 μg/mL), compared to acyclovir as a reference drug (EC50 = 1.8 μg/mL). Moreover, 14 and 15 were found to exhibit valuable activity against HSV-2. Many of the tested compounds demonstrated weak to moderate EC50 values relative to their inactive parent compound (2-amino-1H-benzo[de]isoquinoline-1,3-dione), while compounds 7, 9, 13, 14, 15, 16, 21 and 22 were the most active set of antiviral compounds throughout this study. The cytotoxicity (CC50), EC50, and the selectivity index (SI) values were determined. In a molecular docking study, the ligand-receptor interactions of compounds 124 and their parent with the HSV-1 thymidine kinase active site were investigated using the Molegro Virtual Docker (MVD) software. Based on the potent anti-HSV properties of the previous naphthalimide condensate products, further exploration of this series of 2-amino-1H-benzo[de]isoquinoline-1,3-diones is warranted. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Determination of the Molecular Weight of Low-Molecular-Weight Heparins by Using High-Pressure Size Exclusion Chromatography on Line with a Triple Detector Array and Conventional Methods
Molecules 2015, 20(3), 5085-5098; https://doi.org/10.3390/molecules20035085
Received: 30 January 2015 / Revised: 6 March 2015 / Accepted: 12 March 2015 / Published: 19 March 2015
Cited by 7 | PDF Full-text (919 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The evaluation of weight average molecular weight (Mw) and molecular weight distribution represents one of the most controversial aspects concerning the characterization of low molecular weight heparins (LMWHs). As the most commonly used method for the measurement of such parameters is high performance
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The evaluation of weight average molecular weight (Mw) and molecular weight distribution represents one of the most controversial aspects concerning the characterization of low molecular weight heparins (LMWHs). As the most commonly used method for the measurement of such parameters is high performance size exclusion chromatography (HP-SEC), the soundness of results mainly depends on the appropriate calibration of the chromatographic columns used. With the aim of meeting the requirement of proper Mw standards for LMWHs, in the present work the determination of molecular weight parameters (Mw and Mn) by HP-SEC combined with a triple detector array (TDA) was performed. The HP-SEC/TDA technique permits the evaluation of polymeric samples by exploiting the combined and simultaneous action of three on-line detectors: light scattering detectors (LALLS/RALLS); refractometer and viscometer. Three commercial LMWH samples, enoxaparin, tinzaparin and dalteparin, a γ-ray depolymerized heparin (γ-Hep) and its chromatographic fractions, and a synthetic pentasaccharide were analysed by HP-SEC/TDA. The same samples were analysed also with a conventional HP-SEC method employing refractive index (RI) and UV detectors and two different chromatographic column set, silica gel and polymeric gel columns. In both chromatographic systems, two different calibration curves were built up by using (i) γ-Hep chromatographic fractions and the corresponding Mw parameters obtained via HP-SEC/TDA; (ii) the whole γ-Hep preparation with broad Mw dispersion and the corresponding cumulative distribution function calculated via HP-SEC/TDA. In addition, also a chromatographic column calibration according to European Pharmacopoeia indication was built up. By comparing all the obtained results, some important differences among Mw and size distribution values of the three LMWHs were found with the five different calibration methods and with HP-SEC/TDA method. In particular, the detection of the lower molecular weight components turned out to be the most critical aspect. Whereas HP-SEC/TDA may underestimate species under 2 KDa when present in low concentration, other methods appeared to emphasize their content. Full article
(This article belongs to the Special Issue Glycosaminoglycans and Their Mimetics)
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Open AccessArticle Synthesis of Novel Dihydropyridothienopyrimidin-4,9-dione Derivatives
Molecules 2015, 20(3), 5074-5084; https://doi.org/10.3390/molecules20035074
Received: 27 January 2015 / Revised: 12 March 2015 / Accepted: 13 March 2015 / Published: 19 March 2015
Cited by 2 | PDF Full-text (707 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A novel molecular scaffold, dihydropyridothienopyrimidin-4,9-dione, was synthesized from benzylamine or p-methoxybenzylamine in six steps involving successive ring closure to form a fused ring system composed of dihydropyridone, thiophene and pyrimidone. The pharmacological versatility of the dihydropyridothenopyrimidin-4,9-dione scaffold was demonstrated by inhibitory activity
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A novel molecular scaffold, dihydropyridothienopyrimidin-4,9-dione, was synthesized from benzylamine or p-methoxybenzylamine in six steps involving successive ring closure to form a fused ring system composed of dihydropyridone, thiophene and pyrimidone. The pharmacological versatility of the dihydropyridothenopyrimidin-4,9-dione scaffold was demonstrated by inhibitory activity against metabotropic glutamate receptor subtype 1 (mGluR1), which shows that the title compounds can serve as an interesting scaffold for the discovery of potential bioactive molecules for the treatment of human diseases. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Comparison of Two Species of Notopterygium by GC-MS and HPLC
Molecules 2015, 20(3), 5062-5073; https://doi.org/10.3390/molecules20035062
Received: 19 January 2015 / Revised: 2 March 2015 / Accepted: 4 March 2015 / Published: 19 March 2015
Cited by 9 | PDF Full-text (1579 KB) | HTML Full-text | XML Full-text
Abstract
Notopterygii Rhizoma et Radix (Qianghuo), including Notopterygium incisum Ting ex H. T. Chang (NI) and Notopterygium franchetii H. de Boiss (NF), is an important traditional Chinese medicine. Of these two plants, NI, is more commonly used and has a much higher price in
[...] Read more.
Notopterygii Rhizoma et Radix (Qianghuo), including Notopterygium incisum Ting ex H. T. Chang (NI) and Notopterygium franchetii H. de Boiss (NF), is an important traditional Chinese medicine. Of these two plants, NI, is more commonly used and has a much higher price in the marketplace. To compare these two plants, a combination of gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) was carried out, thus obtaining an overall characterization for both volatile and none-volatile compounds. Combined with hierarchical cluster analysis (HCA) and principal component analysis, GC-MS was successfully applied to distinguish NF and NI. The chemical constitutes of volatile oil in NI and NF were firstly compared in detail, and 1R-alpha-pinene, beta-pinene and 4-isopropyl-1-methyl-1,4-cyclohexadiene had great contribution to the discrimination. Fingerprints of 14 batches of Qinghuo samples were also established based on HPLC, and an obvious difference was found between the two species. The chromatographic fingerprints were further analyzed by similarity analysis and HCA. The present study is the first reported evaluation of two origins of Notopterygii Rhizoma et Radix by GC-MS and HPLC, which will facilitate quality control and its clinical application. Full article
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Open AccessArticle Design, Synthesis and Insecticidal Activity of Novel Phenylurea Derivatives
Molecules 2015, 20(3), 5050-5061; https://doi.org/10.3390/molecules20035050
Received: 28 February 2015 / Revised: 14 March 2015 / Accepted: 17 March 2015 / Published: 19 March 2015
Cited by 1 | PDF Full-text (692 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1
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A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessCommunication (−)-Tarchonanthuslactone Exerts a Blood Glucose-Increasing Effect in Experimental Type 2 Diabetes Mellitus
Molecules 2015, 20(3), 5038-5049; https://doi.org/10.3390/molecules20035038
Received: 8 December 2014 / Revised: 5 March 2015 / Accepted: 6 March 2015 / Published: 19 March 2015
Cited by 2 | PDF Full-text (995 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A number of studies have proposed an anti-diabetic effect for tarchonanthuslactone based on its structural similarity with caffeic acid, a compound known for its blood glucose-reducing properties. However, the actual effect of tarchonanthuslactone on blood glucose level has never been tested. Here, we
[...] Read more.
A number of studies have proposed an anti-diabetic effect for tarchonanthuslactone based on its structural similarity with caffeic acid, a compound known for its blood glucose-reducing properties. However, the actual effect of tarchonanthuslactone on blood glucose level has never been tested. Here, we report that, in opposition to the common sense, tarchonanthuslactone has a glucose-increasing effect in a mouse model of obesity and type 2 diabetes mellitus. The effect is acute and non-cumulative and is present only in diabetic mice. In lean, glucose-tolerant mice, despite a slight increase in blood glucose levels, the effect was not significant. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Secondary Metabolite Localization by Autofluorescence in Living Plant Cells
Molecules 2015, 20(3), 5024-5037; https://doi.org/10.3390/molecules20035024
Received: 3 June 2014 / Revised: 9 February 2015 / Accepted: 25 February 2015 / Published: 19 March 2015
Cited by 19 | PDF Full-text (3125 KB) | HTML Full-text | XML Full-text
Abstract
Autofluorescent molecules are abundant in plant cells and spectral images offer means for analyzing their spectra, yielding information on their accumulation and function. Based on their fluorescence characteristics, an imaging approach using multiphoton microscopy was designed to assess localization of the endogenous fluorophores
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Autofluorescent molecules are abundant in plant cells and spectral images offer means for analyzing their spectra, yielding information on their accumulation and function. Based on their fluorescence characteristics, an imaging approach using multiphoton microscopy was designed to assess localization of the endogenous fluorophores in living plant cells. This method, which requires no previous treatment, provides an effective experimental tool for discriminating between multiple naturally-occurring fluorophores in living-tissues. Combined with advanced Linear Unmixing, the spectral analysis extends the possibilities and enables the simultaneous detection of fluorescent molecules reliably separating overlapping emission spectra. However, as with any technology, the possibility for artifactual results does exist. This methodological article presents an overview of the applications of tissular and intra-cellular localization of these intrinsic fluorophores in leaves and fruits (here for coffee and vanilla). This method will provide new opportunities for studying cellular environments and the behavior of endogenous fluorophores in the intracellular environment. Full article
(This article belongs to the Special Issue Fluorescent Probes)
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Open AccessArticle Auto-Thermal Reforming Using Mixed Ion-Electronic Conducting Ceramic Membranes for a Small-Scale H2 Production Plant
Molecules 2015, 20(3), 4998-5023; https://doi.org/10.3390/molecules20034998
Received: 19 January 2015 / Accepted: 11 March 2015 / Published: 18 March 2015
Cited by 3 | PDF Full-text (1267 KB) | HTML Full-text | XML Full-text
Abstract
The integration of mixed ionic electronic conducting (MIEC) membranes for air separation in a small-to-medium scale unit for H2 production (in the range of 650–850 Nm3/h) via auto-thermal reforming of methane has been investigated in the present study. Membranes based
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The integration of mixed ionic electronic conducting (MIEC) membranes for air separation in a small-to-medium scale unit for H2 production (in the range of 650–850 Nm3/h) via auto-thermal reforming of methane has been investigated in the present study. Membranes based on mixed ionic electronic conducting oxides such as Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) give sufficiently high oxygen fluxes at temperatures above 800 °C with high purity (higher than 99%). Experimental results of membrane permeation tests are presented and used for the reactor design with a detailed reactor model. The assessment of the H2 plant has been carried out for different operating conditions and reactor geometry and an energy analysis has been carried out with the flowsheeting software Aspen Plus, including also the turbomachines required for a proper thermal integration. A micro-gas turbine is integrated in the system in order to supply part of the electricity required in the system. The analysis of the system shows that the reforming efficiency is in the range of 62%–70% in the case where the temperature at the auto-thermal reforming membrane reactor (ATR-MR) is equal to 900 °C. When the electric consumption and the thermal export are included the efficiency of the plant approaches 74%–78%. The design of the reactor has been carried out using a reactor model linked to the Aspen flowsheet and the results show that with a larger reactor volume the performance of the system can be improved, especially because of the reduced electric consumption. From this analysis it has been found that for a production of about 790 Nm3/h pure H2, a reactor with a diameter of 1 m and length of 1.8 m with about 1500 membranes of 2 cm diameter is required. Full article
(This article belongs to the Special Issue Methane Reforming)
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Open AccessReview Synthesis of C-Arylnucleoside Analogues
Molecules 2015, 20(3), 4967-4997; https://doi.org/10.3390/molecules20034967
Received: 24 January 2015 / Accepted: 10 March 2015 / Published: 18 March 2015
Cited by 4 | PDF Full-text (1086 KB) | HTML Full-text | XML Full-text
Abstract
Modified nucleoside analogues are of great biological importance as antiviral and antitumoral agents. There is special interest in the preparation of C-aryl nucleosides with an aromatic ring in different positions of the glycone for their biological activity. Different chemical synthesis strategies for
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Modified nucleoside analogues are of great biological importance as antiviral and antitumoral agents. There is special interest in the preparation of C-aryl nucleosides with an aromatic ring in different positions of the glycone for their biological activity. Different chemical synthesis strategies for these targets are described in this review. Full article
(This article belongs to the Special Issue 20th Anniversary of Molecules—Recent Advances in Organic Chemistry)
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Open AccessArticle Determination of Phenolic Compounds and Antioxidant Activity in Leaves from Wild Rubus L. Species
Molecules 2015, 20(3), 4951-4966; https://doi.org/10.3390/molecules20034951
Received: 1 December 2014 / Accepted: 10 March 2015 / Published: 18 March 2015
Cited by 9 | PDF Full-text (791 KB) | HTML Full-text | XML Full-text
Abstract
Twenty-six different wild blackberry leaf samples were harvested from various localities throughout southeastern Poland. Leaf samples were assessed regarding their phenolic compound profiles and contents by LC/MS QTOF, and their antioxidant activity by ABTS and FRAP. Thirty-three phenolic compounds were detected (15 flavonols,
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Twenty-six different wild blackberry leaf samples were harvested from various localities throughout southeastern Poland. Leaf samples were assessed regarding their phenolic compound profiles and contents by LC/MS QTOF, and their antioxidant activity by ABTS and FRAP. Thirty-three phenolic compounds were detected (15 flavonols, 13 hydroxycinnamic acids, three ellagic acid derivatives and two flavones). Ellagic acid derivatives were the predominant compounds in the analyzed leaves, especially sanguiin H-6, ellagitannins, lambertianin C, and casuarinin. The content of phenolic compounds was significantly correlated with the antioxidant activity of the analyzed samples. The highest level of phenolic compounds was measured for R. perrobustus, R. wimmerianus, R. pedemontanus and R. grabowskii. The study showed that wild blackberry leaves can be considered a good source of antioxidant compounds. There is clear potential for the utilization of blackberry leaves as a food additive, medicinal source or herbal tea. Full article
(This article belongs to the Section Metabolites)
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Open AccessArticle Cysteine Specific Targeting of the Functionally Distinct Peroxiredoxin and Glutaredoxin Proteins by the Investigational Disulfide BNP7787
Molecules 2015, 20(3), 4928-4950; https://doi.org/10.3390/molecules20034928
Received: 10 November 2014 / Accepted: 5 March 2015 / Published: 18 March 2015
Cited by 4 | PDF Full-text (2994 KB) | HTML Full-text | XML Full-text
Abstract
Glutaredoxin (Grx), peroxiredoxin (Prx), and thioredoxin (Trx) are redoxin family proteins that catalyze different types of chemical reactions that impact cell growth and survival through functionally distinct intracellular pathways. Much research is focused on understanding the roles of these redoxin proteins in the
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Glutaredoxin (Grx), peroxiredoxin (Prx), and thioredoxin (Trx) are redoxin family proteins that catalyze different types of chemical reactions that impact cell growth and survival through functionally distinct intracellular pathways. Much research is focused on understanding the roles of these redoxin proteins in the development and/or progression of human diseases. Grx and Prx are overexpressed in human cancers, including human lung cancers. BNP7787 is a novel investigational agent that has been evaluated in previous clinical studies, including non-small cell lung cancer (NSCLC) studies. Herein, data from activity assays, mass spectrometry analyses, and X-ray crystallographic studies indicate that BNP7787 forms mixed disulfides with select cysteine residues on Grx and Prx and modulates their function. Studies of interactions between BNP7787 and Trx have been conducted and reported separately. Despite the fact that Trx, Grx, and Prx are functionally distinct proteins that impact oxidative stress, cell proliferation and disease processes through different intracellular pathways, BNP7787 can modify each protein and appears to modulate function through mechanisms that are unique to each target protein. Tumor cells are often genomically heterogeneous containing subpopulations of cancer cells that often express different tumor-promoting proteins or that have multiple dysregulated signaling pathways modulating cell proliferation and drug resistance. A multi-targeted agent that simultaneously modulates activity of proteins important in mediating cell proliferation by functionally distinct intracellular pathways could have many potentially useful therapeutic applications. Full article
(This article belongs to the Special Issue Thioredoxin and Glutathione Systems)
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Open AccessArticle Understanding the Physicochemical Properties of Mitragynine, a Principal Alkaloid of Mitragyna speciosa, for Preclinical Evaluation
Molecules 2015, 20(3), 4915-4927; https://doi.org/10.3390/molecules20034915
Received: 12 January 2015 / Accepted: 27 February 2015 / Published: 18 March 2015
Cited by 7 | PDF Full-text (720 KB) | HTML Full-text | XML Full-text
Abstract
Varied pharmacological responses have been reported for mitragynine in the literature, but no supportive scientific explanations have been given for this. These studies have been undertaken without a sufficient understanding of the physicochemical properties of mitragynine. In this work a UV spectrophotometer approach
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Varied pharmacological responses have been reported for mitragynine in the literature, but no supportive scientific explanations have been given for this. These studies have been undertaken without a sufficient understanding of the physicochemical properties of mitragynine. In this work a UV spectrophotometer approach and HPLC-UV method were employed to ascertain the physicochemical properties of mitragynine. The pKa of mitragynine measured by conventional UV (8.11 ± 0.11) was in agreement with the microplate reader determination (8.08 ± 0.04). Mitragynine is a lipophilic alkaloid, as indicated by a logP value of 1.73. Mitragynine had poor solubility in water and basic media, and conversely in acidic environments, but it is acid labile. In an in vitro dissolution the total drug release was higher for the simulated gastric fluid but was prolonged and incomplete for the simulated intestinal fluid. The hydrophobicity, poor water solubility, high variability of drug release in simulated biological fluids and acid degradable characteristics of mitragynine probably explain the large variability of its pharmacological responses reported in the literature. The determined physicochemical properties of mitragynine will provide a basis for developing a suitable formulation to further improve its solubility, stability and oral absorption for better assessment of this compound in preclinical studies. Full article
(This article belongs to the Special Issue Alkaloids: Novel Therapeutic Perspectives)
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Open AccessArticle Preliminary Biological Evaluation of 18F-FBEM-Cys-Annexin V a Novel Apoptosis Imaging Agent
Molecules 2015, 20(3), 4902-4914; https://doi.org/10.3390/molecules20034902
Received: 22 December 2014 / Revised: 24 February 2015 / Accepted: 6 March 2015 / Published: 17 March 2015
Cited by 9 | PDF Full-text (1737 KB) | HTML Full-text | XML Full-text
Abstract
A novel annexin V derivative (Cys-Annexin V) with a single cysteine residue at its C-terminal has been developed and successfully labeled site-specifically with 18F-FBEM. 18F-FBEM was synthesized by coupling 18F-fluorobenzoic acid (18F-FBA) with N-(2-aminoethyl)maleimide using optimized reaction conditions.
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A novel annexin V derivative (Cys-Annexin V) with a single cysteine residue at its C-terminal has been developed and successfully labeled site-specifically with 18F-FBEM. 18F-FBEM was synthesized by coupling 18F-fluorobenzoic acid (18F-FBA) with N-(2-aminoethyl)maleimide using optimized reaction conditions. The yield of 18F-FBEM-Cys-Annexin V was 71.5% ± 2.0% (n = 4, based on the starting 18F-FBEM, non-decay corrected). The radiochemical purity of 18F-FBEM-Cys-Annexin V was >95%. The specific radioactivities of 18F-FBEM and 18F-FBEM-Cys-Annexin V were >150 and 3.17 GBq/µmol, respectively. Like the 1st generation 18F-SFB-Annexin V, the novel 18F-FBEM-Cys-Annexin V mainly shows renal and to a lesser extent, hepatobiliary excretion in normal mice. In rat hepatic apoptosis models a 3.88 ± 0.05 (n = 4, 1 h) and 10.35 ± 0.08 (n = 4, 2 h) increase in hepatic uptake of 18F-FBEM-Cys-Annexin V compared to normal rats was observed after injection via the tail vein. The liver uptake ratio (treated/control) at 2 h p.i. as measured via microPET correlated with the ratio of apoptotic nuclei in liver observed using TUNEL histochemistry, indicating that the novel 18F-FBEM-Cys-Annexin V is a potential apoptosis imaging agent. Full article
(This article belongs to the Special Issue Preparation of Radiopharmaceuticals and Their Use in Drug Development)
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Open AccessReview Modification of Purine and Pyrimidine Nucleosides by Direct C-H Bond Activation
Molecules 2015, 20(3), 4874-4901; https://doi.org/10.3390/molecules20034874
Received: 15 February 2015 / Revised: 11 March 2015 / Accepted: 13 March 2015 / Published: 17 March 2015
Cited by 18 | PDF Full-text (1785 KB) | HTML Full-text | XML Full-text
Abstract
Transition metal-catalyzed modifications of the activated heterocyclic bases of nucleosides as well as DNA or RNA fragments employing traditional cross-coupling methods have been well-established in nucleic acid chemistry. This review covers advances in the area of cross-coupling reactions in which nucleosides are functionalized
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Transition metal-catalyzed modifications of the activated heterocyclic bases of nucleosides as well as DNA or RNA fragments employing traditional cross-coupling methods have been well-established in nucleic acid chemistry. This review covers advances in the area of cross-coupling reactions in which nucleosides are functionalized via direct activation of the C8-H bond in purine and the C5-H or C6-H bond in uracil bases. The review focuses on Pd/Cu-catalyzed couplings between unactivated nucleoside bases with aryl halides. It also discusses cross-dehydrogenative arylations and alkenylations as well as other reactions used for modification of nucleoside bases that avoid the use of organometallic precursors and involve direct C-H bond activation in at least one substrate. The scope and efficiency of these coupling reactions along with some mechanistic considerations are discussed. Full article
(This article belongs to the Special Issue Nucleoside Modifications) Printed Edition available
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Open AccessArticle QSAR-Assisted Virtual Screening of Lead-Like Molecules from Marine and Microbial Natural Sources for Antitumor and Antibiotic Drug Discovery
Molecules 2015, 20(3), 4848-4873; https://doi.org/10.3390/molecules20034848
Received: 29 January 2015 / Revised: 27 February 2015 / Accepted: 4 March 2015 / Published: 17 March 2015
Cited by 5 | PDF Full-text (909 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A Quantitative Structure-Activity Relationship (QSAR) approach for classification was used for the prediction of compounds as active/inactive relatively to overall biological activity, antitumor and antibiotic activities using a data set of 1746 compounds from PubChem with empirical CDK descriptors and semi-empirical quantum-chemical descriptors.
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A Quantitative Structure-Activity Relationship (QSAR) approach for classification was used for the prediction of compounds as active/inactive relatively to overall biological activity, antitumor and antibiotic activities using a data set of 1746 compounds from PubChem with empirical CDK descriptors and semi-empirical quantum-chemical descriptors. A data set of 183 active pharmaceutical ingredients was additionally used for the external validation of the best models. The best classification models for antibiotic and antitumor activities were used to screen a data set of marine and microbial natural products from the AntiMarin database—25 and four lead compounds for antibiotic and antitumor drug design were proposed, respectively. The present work enables the presentation of a new set of possible lead like bioactive compounds and corroborates the results of our previous investigations. By other side it is shown the usefulness of quantum-chemical descriptors in the discrimination of biologically active and inactive compounds. None of the compounds suggested by our approach have assigned non-antibiotic and non-antitumor activities in the AntiMarin database and almost all were lately reported as being active in the literature. Full article
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Open AccessArticle Identification of the Valid Reference Genes for Quantitative RT-PCR in Annual Ryegrass (Lolium multiflorum) under Salt Stress
Molecules 2015, 20(3), 4833-4847; https://doi.org/10.3390/molecules20034833
Received: 5 January 2015 / Revised: 6 March 2015 / Accepted: 10 March 2015 / Published: 16 March 2015
Cited by 6 | PDF Full-text (2822 KB) | HTML Full-text | XML Full-text
Abstract
Annual ryegrass (Lolium multiflorum) is a cool-season annual grass cultivated worldwide for its high yield and quality. With the areas of saline soil increasing, investigation of the molecular mechanisms of annual ryegrass tolerance under salt stress has become a significant topic.
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Annual ryegrass (Lolium multiflorum) is a cool-season annual grass cultivated worldwide for its high yield and quality. With the areas of saline soil increasing, investigation of the molecular mechanisms of annual ryegrass tolerance under salt stress has become a significant topic. qRT-PCR has been a predominant assay for determination of the gene expression, in which selecting a valid internal reference gene is a crucial step. The objective of present study was to evaluate and identify suitable reference genes for qRT-PCR in annual ryegrass under salt stress. The results calculated by RefFinder indicated that eEF1A(s) was the most stable reference gene in leaves, whereas EF1-a was the least stable; meanwhile, TBP-1 was the most optimal in roots and in all samples, and the eIF-5A shouldn’t be utilized for normalization of the gene expression. eEF1A(s) is more suitable than TBP-1 as reference gene in leaves when verified with P5CS1 and Cyt-Cu/Zn SOD genes. We should choose optimal reference genes in specific tissues instead of the most stable one selected from different conditions and tissues. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle In Vitro Neuroprotective Activities of Compounds from Angelica shikokiana Makino
Molecules 2015, 20(3), 4813-4832; https://doi.org/10.3390/molecules20034813
Received: 5 February 2015 / Revised: 3 March 2015 / Accepted: 9 March 2015 / Published: 16 March 2015
Cited by 10 | PDF Full-text (2012 KB) | HTML Full-text | XML Full-text
Abstract
Angelica shikokiana is widely marketed in Japan as a dietary food supplement. With a focus on neurodegenerative conditions such as Alzheimer’s disease, the aerial part was extracted and through bio-guided fractionation, fifteen compounds [α-glutinol, β-amyrin, kaempferol, luteolin, quercetin, kaempferol-3-O-glucoside, kaempferol-3-O
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Angelica shikokiana is widely marketed in Japan as a dietary food supplement. With a focus on neurodegenerative conditions such as Alzheimer’s disease, the aerial part was extracted and through bio-guided fractionation, fifteen compounds [α-glutinol, β-amyrin, kaempferol, luteolin, quercetin, kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, methyl chlorogenate, chlorogenic acid, hyuganin E, 5-(hydroxymethyl)-2-furaldehyde, β-sitosterol-3-O-glucoside, adenosine (isolated for the first time from A. shikokiana), isoepoxypteryxin and isopteryxin] were isolated. Isolated compounds were evaluated for in vitro neuroprotection using acetylcholine esterase inhibitory, protection against hydrogen peroxide and amyloid β peptide (Aβ25-35)-induced neurotoxicity in neuro-2A cells, scavenging of hydroxyl radicals and intracellular reactive oxygen species and thioflavin T assays. Quercetin showed the strongest AChE inhibition (IC50 value = 35.5 µM) through binding to His-440 and Tyr-70 residues at the catalytic and anionic sites of acetylcholine esterase, respectively. Chlorogenic acid, its methyl ester, quercetin and luteolin could significantly protect neuro-2A cells against H2O2-induced neurotoxicity and scavenge hydroxyl radical and intracellular reactive oxygen species. Kaempferol-3-O-rutinoiside, hyuganin E and isoepoxypteryxin significantly decreased Aβ25-35-induced neurotoxicity and Th-T fluorescence. To the best of our knowledge, this is the first report about neuroprotection of hyuganin E and isoepoxypteryxin against Aβ25-35-induced neurotoxicity. Full article
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Open AccessReview QM/MM Calculations with deMon2k
Molecules 2015, 20(3), 4780-4812; https://doi.org/10.3390/molecules20034780
Received: 19 September 2014 / Revised: 25 February 2015 / Accepted: 2 March 2015 / Published: 16 March 2015
Cited by 7 | PDF Full-text (2130 KB) | HTML Full-text | XML Full-text
Abstract
The density functional code deMon2k employs a fitted density throughout (Auxiliary Density Functional Theory), which offers a great speed advantage without sacrificing necessary accuracy. Powerful Quantum Mechanical/Molecular Mechanical (QM/MM) approaches are reviewed. Following an overview of the basic features of deMon2k that make
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The density functional code deMon2k employs a fitted density throughout (Auxiliary Density Functional Theory), which offers a great speed advantage without sacrificing necessary accuracy. Powerful Quantum Mechanical/Molecular Mechanical (QM/MM) approaches are reviewed. Following an overview of the basic features of deMon2k that make it efficient while retaining accuracy, three QM/MM implementations are compared and contrasted. In the first, deMon2k is interfaced with the CHARMM MM code (CHARMM-deMon2k); in the second MM is coded directly within the deMon2k software; and in the third the Chemistry in Ruby (Cuby) wrapper is used to drive the calculations. Cuby is also used in the context of constrained-DFT/MM calculations. Each of these implementations is described briefly; pros and cons are discussed and a few recent applications are described briefly. Applications include solvated ions and biomolecules, polyglutamine peptides important in polyQ neurodegenerative diseases, copper monooxygenases and ultra-rapid electron transfer in cryptochromes. Full article
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Open AccessArticle Cyclic Comonomers for the Synthesis of Carboxylic Acid and Amine Functionalized Poly(l-Lactic Acid)
Molecules 2015, 20(3), 4764-4779; https://doi.org/10.3390/molecules20034764
Received: 15 January 2015 / Revised: 23 February 2015 / Accepted: 2 March 2015 / Published: 16 March 2015
Cited by 5 | PDF Full-text (694 KB) | HTML Full-text | XML Full-text
Abstract
Degradable aliphatic polyesters such as poly(lactic acid) are widely used in biomedical applications, however, they lack functional moieties along the polymer backbone that are amenable for functionalization reactions or could be the basis for interactions with biological systems. Here we present a straightforward
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Degradable aliphatic polyesters such as poly(lactic acid) are widely used in biomedical applications, however, they lack functional moieties along the polymer backbone that are amenable for functionalization reactions or could be the basis for interactions with biological systems. Here we present a straightforward route for the synthesis of functional α-ω epoxyesters as comonomers for lactide polymerization. Salient features of these highly functionalized epoxides are versatility in functionality and a short synthetic route of less than four steps. The α-ω epoxyesters presented serve as a means to introduce carboxylic acid and amine functional groups into poly(lactic acid) polymers via ring-opening copolymerization. Full article
(This article belongs to the Special Issue Ring-Opening Polymerization)
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Open AccessArticle Protective Effects of Labisia pumila var. alata on Biochemical and Histopathological Alterations of Cardiac Muscle Cells in Isoproterenol-Induced Myocardial Infarction Rats
Molecules 2015, 20(3), 4746-4763; https://doi.org/10.3390/molecules20034746
Received: 31 January 2015 / Revised: 20 February 2015 / Accepted: 4 March 2015 / Published: 16 March 2015
Cited by 12 | PDF Full-text (1655 KB) | HTML Full-text | XML Full-text
Abstract
The study was designed to evaluate the cardioprotective effects of the standardized aqueous and 80% ethanol extracts of Labisia pumila var. alata (LPva) in isoproterenol (ISO)-induced myocardial infarction (MI) in rats. The extracts were administered to Wistar rats orally for 28 days with
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The study was designed to evaluate the cardioprotective effects of the standardized aqueous and 80% ethanol extracts of Labisia pumila var. alata (LPva) in isoproterenol (ISO)-induced myocardial infarction (MI) in rats. The extracts were administered to Wistar rats orally for 28 days with three doses (100, 200 and 400 mg/kg of body weight) prior to ISO (85 mg/kg)-induced MI in two doses on day 29 and 30. The sera and hearts were collected for biochemical and histopathological analysis after the rats were sacrificed 48 h after the first induction. The main components of the extracts, gallic acid, alkylresorcinols and flavonoids were identified and quantitatively analyzed in the extracts by using a validated reversed phase HPLC method. The extracts showed significant protective effects as pretreated rats showed a significant dose-dependent decrease (p < 0.05) in cardiac enzyme activities, i.e., cardiac troponin I (cTnI), creatine kinase MB isoenzyme (CK-MB), lactate dehydrogenase (LDH), alanine transaminase (ALT) and aspartate transaminase (AST), when compared with ISO-control rats. There were significant rises (p < 0.05) in the activity of oxidase enzymes, i.e., glutathione peroxide (GPx), catalase (CAT) and superoxide dismutase (SOD) of the pretreated rats, when compared with ISO-control group. Histopathological examination showed an improvement in membrane cell integrity in pre-treated rats compared to untreated rats. The major components of LPva extracts can be used as their biomarkers and contributed to the cardioprotective effects against ISO-induced MI rats. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Chemical Composition and Biological Activities of the Essential Oil of Skimmia laureola Leaves
Molecules 2015, 20(3), 4735-4745; https://doi.org/10.3390/molecules20034735
Received: 22 January 2015 / Revised: 10 March 2015 / Accepted: 12 March 2015 / Published: 16 March 2015
Cited by 6 | PDF Full-text (768 KB) | HTML Full-text | XML Full-text
Abstract
The composition of the essential oil from leaves of Skimmia laureola was determined by GC and GC-MS. Twenty-eight components were identified, accounting for 93.9% of the total oil. The oil is mainly composed of monoterpenes (93.5%), of which monoterpene hydrocarbons and oxygenated monoterpenes
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The composition of the essential oil from leaves of Skimmia laureola was determined by GC and GC-MS. Twenty-eight components were identified, accounting for 93.9% of the total oil. The oil is mainly composed of monoterpenes (93.5%), of which monoterpene hydrocarbons and oxygenated monoterpenes represent 11.0% and 82.5%, respectively. Sesquiterpenes constitute only 0.3% of the total oil. Linalyl acetate is the main component (50.5%), with linalool (13.1%), geranyl acetate (8.5%) and cis-p-menth-2-en-1-ol (6.2%) as other principal constituents. The essential oil showed a significant antispasmodic activity, in a dose range of 0.03–10 mg/mL. The essential oil also possesses antibacterial and antifungal activities against some pathogenic strains. The phytotoxic and cytotoxic activities were also assessed. Full article
(This article belongs to the collection Recent Advances in Flavors and Fragrances)
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