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Molecules, Volume 18, Issue 9 (September 2013), Pages 10095-11657

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Open AccessArticle A Modular Approach to Triazole-Containing Chemical Inducers of Dimerisation for Yeast Three-Hybrid Screening
Molecules 2013, 18(9), 11639-11657; https://doi.org/10.3390/molecules180911639
Received: 1 August 2013 / Revised: 5 September 2013 / Accepted: 6 September 2013 / Published: 23 September 2013
Cited by 7 | PDF Full-text (1196 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The yeast three-hybrid (Y3H) approach shows considerable promise for the unbiased identification of novel small molecule-protein interactions. In recent years, it has been successfully used to link a number of bioactive molecules to novel protein binding partners. However despite its potential importance as
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The yeast three-hybrid (Y3H) approach shows considerable promise for the unbiased identification of novel small molecule-protein interactions. In recent years, it has been successfully used to link a number of bioactive molecules to novel protein binding partners. However despite its potential importance as a protein target identification method, the Y3H technique has not yet been widely adopted, in part due to the challenges associated with the synthesis of the complex chemical inducers of dimerisation (CIDs). The development of a modular approach using potentially “off the shelf” synthetic components was achieved and allowed the synthesis of a family of four triazole-containing CIDs, MTX-Cmpd2.2-2.5. These CIDs were then compared using the Y3H approach with three of them giving a strong positive interaction with a known target of compound 2, TgCDPK1. These results showed that the modular nature of our synthetic strategy may help to overcome the challenges currently encountered with CID synthesis and should contribute to the Y3H approach reaching its full potential as an unbiased target identification strategy. Full article
(This article belongs to the Special Issue Reagents and Methods for Protein Target Identification)
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Open AccessArticle Bioactivity-Guided Fractionation of Physical Fatigue-Attenuating Components from Rubus parvifolius L.
Molecules 2013, 18(9), 11624-11638; https://doi.org/10.3390/molecules180911624
Received: 19 July 2013 / Revised: 25 August 2013 / Accepted: 6 September 2013 / Published: 23 September 2013
Cited by 5 | PDF Full-text (278 KB) | HTML Full-text | XML Full-text
Abstract
Alleviation of fatigue has been emerging as a serious issue that requires urgent attention. Health professionals and sports physiologists have been looking for active natural products and synthetic compounds to overcome fatigue in humans. This study was designed to define the anti-fatigue property
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Alleviation of fatigue has been emerging as a serious issue that requires urgent attention. Health professionals and sports physiologists have been looking for active natural products and synthetic compounds to overcome fatigue in humans. This study was designed to define the anti-fatigue property of Rubus parvifolius L. (RPL) by characterization of active constituents using a mouse forced swimming test model. Four RPL fractions with different polarities containing anti-fatigue activity were sequentially isolated from the n-butanol RPL extract, followed by elution of 50% ethanol-water fraction from D101 macroporous resin chromatography to obtain nigaichigoside F1, suavissimoside R1 and coreanoside F1. Active constituents of the 50% ethanol-water eluate of RPL were total saponins. The fractions were examined based on the effect on weight-loaded swimming capacity of mice. Serum levels of urea nitrogen (SUN), triglyceride fatty acids (TG), lactate dehydrogenase (LDH), lactic acid (LA), ammonia and hepatic glycogen (HG) were also examined for potential mechanisms underlying the anti-fatigue effect of RPL extracts. During the experiment, two inflammatory markers, interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) in serum, were measured. We found that total saponins from RPL possess potent capabilities to alleviate mouse fatigue induced by forced swimming and that nigaichigoside F1 was responsible for the pharmacological effect. The underlying mechanisms include delays of SUN and LA accumulation, a decrease in TG level by increasing fat consumption, increases in HG and LDH so that lactic acid accumulation and ammonia in the muscle were reduced, and suppression of increased immune activation and inflammatory cytokine production. Our findings will be helpful for functional identification of novel anti-fatigue components from natural medicinal herbs. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Combined Effects of Green Tea Extracts, Green Tea Polyphenols or Epigallocatechin Gallate with Acarbose on Inhibition against α-Amylase and α-Glucosidase in Vitro
Molecules 2013, 18(9), 11614-11623; https://doi.org/10.3390/molecules180911614
Received: 7 August 2013 / Revised: 13 September 2013 / Accepted: 16 September 2013 / Published: 18 September 2013
Cited by 31 | PDF Full-text (526 KB) | HTML Full-text | XML Full-text
Abstract
Green tea, green tea polyphenols and epigallocatechin gallate (EGCG) are confirmed to have beneficial effects in the treatment of diabetes mellitus, and a possible mechanism can be ascribed to their inhibitory effect against α-amylase and α-glucosidase in the digestive tract. In this paper,
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Green tea, green tea polyphenols and epigallocatechin gallate (EGCG) are confirmed to have beneficial effects in the treatment of diabetes mellitus, and a possible mechanism can be ascribed to their inhibitory effect against α-amylase and α-glucosidase in the digestive tract. In this paper, we first investigated the combined inhibitory effect of green tea extracts, green tea polyphenols or EGCG with acarbose on α-amylase and α-glucosidase in vitro. Our results indicated that the interaction between green tea extracts (green tea polyphenols or EGCG) and acarbose was complicated. The combination of green tea extracts, green tea polyphenols or EGCG with acarbose had a synergistic effect on α-amylase and α-glucosidase at low concentrations and the combined effect turned out to be antagonistic at high concentrations according to the Combination Index (CI) values. These findings not only provided some significant quantitative values, but also provide some valuable implications for the combined use of acarbose and GTE (GTP or EGCG) in the treatment of diabetes mellitus. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Solution Properties and in Vitro Anti-Tumor Activities of Polysaccharides from Longan Pulp
Molecules 2013, 18(9), 11601-11613; https://doi.org/10.3390/molecules180911601
Received: 13 June 2013 / Revised: 28 August 2013 / Accepted: 11 September 2013 / Published: 18 September 2013
Cited by 13 | PDF Full-text (586 KB) | HTML Full-text | XML Full-text
Abstract
The solution properties of four fractions (LPI–IV) from crude longan pulp polysaccharides (LP3) were analyzed by size-exclusion chromatography combined with laser light scattering, viscometry, complex formation with Congo red, and atomic force microscopy. Their radii of gyration (<S2>z1/2)
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The solution properties of four fractions (LPI–IV) from crude longan pulp polysaccharides (LP3) were analyzed by size-exclusion chromatography combined with laser light scattering, viscometry, complex formation with Congo red, and atomic force microscopy. Their radii of gyration (<S2>z1/2) were 43.3, 62.6, 43.2 and 77.3 nm, exponents of <S2>z1/2 = k Mwv were 0.04, 0.50, 0.52 and 0.02, and intrinsic viscosities ([η]) were 9.945, 25.38, 308.2 and 452.1 mL/g, respectively. Moreover, the dependence of [η] on Mw was established to be [η] = 5.3 × 10−2Mw0.61 (mL/g). LPI had both a sphere-like conformation and a triple-helix structure, and LPII–IV existed as flexible chains. LP3, LPI, LPII and LPIII all exhibited direct inhibitory effects on A549, HeLa and HepG2 cells in a positive dose-dependent manner in the range of 50–400 µg/mL. The activities of LPIII, especially the inhibition of HepG2 cell proliferation, were stronger than those of others, which may be partly related to its flexible conformation. The present results support the cancer therapeutic potential of longan polysaccharides. Full article
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Open AccessReview Plasticity of the Human Olfactory System: The Olfactory Bulb
Molecules 2013, 18(9), 11586-11600; https://doi.org/10.3390/molecules180911586
Received: 15 August 2013 / Revised: 3 September 2013 / Accepted: 11 September 2013 / Published: 17 September 2013
Cited by 37 | PDF Full-text (1392 KB) | HTML Full-text | XML Full-text
Abstract
In the last years, an increasing interest has been paid to the olfactory system, particularly to its abilities of plasticity and its potential continuous neurogenesis throughout adult life. Although mechanisms underlying adult neurogenesis have been largely investigated in animals, to some degree they
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In the last years, an increasing interest has been paid to the olfactory system, particularly to its abilities of plasticity and its potential continuous neurogenesis throughout adult life. Although mechanisms underlying adult neurogenesis have been largely investigated in animals, to some degree they remain unclear in humans. Based on human research findings, the present review will focus on the olfactory bulb as an evidence of the astonishing plasticity of the human olfactory system. Full article
(This article belongs to the Special Issue Flavors and Fragrances)
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Open AccessArticle Synthesis of a Novel Carbocyclic Analog of Bredinin
Molecules 2013, 18(9), 11576-11585; https://doi.org/10.3390/molecules180911576
Received: 23 August 2013 / Revised: 5 September 2013 / Accepted: 10 September 2013 / Published: 17 September 2013
Cited by 1 | PDF Full-text (248 KB) | HTML Full-text | XML Full-text
Abstract
The natural nucleoside antibiotic, bredinin, exhibits antiviral and other biological activities. While various nucleosides related to bredinin have been synthesized, its carbocyclic analog has remained unknown. Synthesis of this heretofore unknown analog of bredinin is described. The key precursor, (3aS,4R
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The natural nucleoside antibiotic, bredinin, exhibits antiviral and other biological activities. While various nucleosides related to bredinin have been synthesized, its carbocyclic analog has remained unknown. Synthesis of this heretofore unknown analog of bredinin is described. The key precursor, (3aS,4R,6R,6aR)-6-((methoxy-methoxy)methyl)-2,2-dimethyltetrahydro-3aH-cyclopenta[d][1,3]dioxol-4-amine (5), was prepared from the commercially available compound, (1R,4S)-2-azabicyclo[2.2.1] hept-5-en-3-one (4). Our initial approach used intermediate 6, derived in three transformations from 5, for the key photolytic step to produce the desired ring-opened precursor to the target compound. This photochemical transformation was unsuccessful. However, an appropriately protected and related precursor was synthesized from 5 through the following side-chain functional group transformations: elaboration of the amino group through malonyl ester formation, oximation at the central carbon, conversion of ester to amide and catalytic reduction of the oxime group. This precursor, on treatment with triethylorthoformate and catalytic acetic acid in ethanol, underwent cyclization to produce the desired 4-carbamoyl-imidazolium-5-olate ring. Deprotection of the latter product proceeded smoothly to give the carbocyclic analog of bredinin. This target molecule exhibits antiviral activity, albeit low, against a number of RNA viruses. Further biological evaluations are in progress. Full article
(This article belongs to the Special Issue Synthesis of Nucleosides, Nucleotides and Their Derivatives)
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Open AccessArticle A pH-Sensitive Peptide-Containing Lasso Molecular Switch
Molecules 2013, 18(9), 11553-11575; https://doi.org/10.3390/molecules180911553
Received: 24 July 2013 / Revised: 9 September 2013 / Accepted: 11 September 2013 / Published: 17 September 2013
Cited by 19 | PDF Full-text (2753 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The synthesis of a peptide-containing lasso molecular switch by a self-entanglement strategy is described. The interlocked [1] rotaxane molecular machine consists of a benzometaphenylene[25]crown-8 (BMP25C8) macrocycle surrounding a molecular axle. This molecular axle contains a tripeptidic sequence and two molecular stations: a N
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The synthesis of a peptide-containing lasso molecular switch by a self-entanglement strategy is described. The interlocked [1] rotaxane molecular machine consists of a benzometaphenylene[25]crown-8 (BMP25C8) macrocycle surrounding a molecular axle. This molecular axle contains a tripeptidic sequence and two molecular stations: a N-benzyltriazolium and a pH-sensitive anilinium station. The tripeptide is located between the macrocycle and the triazolium station, so that its conformation can be tailored depending on the shuttling of the macrocycle from one station to the other. At acidic pH, the macrocycle resides around the anilinium moiety, whereas it shuttles around the triazolium station after deprotonation. This molecular machinery thus forces the lasso to adopt a tightened or a loosened conformation. Full article
(This article belongs to the Special Issue Rotaxanes)
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Open AccessArticle Analysis of Biotinylated Generation 4 Poly(amidoamine) (PAMAM) Dendrimer Distribution in the Rat Brain and Toxicity in a Cellular Model of the Blood-Brain Barrier
Molecules 2013, 18(9), 11537-11552; https://doi.org/10.3390/molecules180911537
Received: 23 July 2013 / Revised: 3 September 2013 / Accepted: 10 September 2013 / Published: 17 September 2013
Cited by 12 | PDF Full-text (3257 KB) | HTML Full-text | XML Full-text
Abstract
Dendrimers are highly customizable nanopolymers with qualities that make them ideal for drug delivery. The high binding affinity of biotin/avidin provides a useful approach to fluorescently label synthesized dendrimer-conjugates in cells and tissues. In addition, biotin may facilitate delivery of dendrimers through the
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Dendrimers are highly customizable nanopolymers with qualities that make them ideal for drug delivery. The high binding affinity of biotin/avidin provides a useful approach to fluorescently label synthesized dendrimer-conjugates in cells and tissues. In addition, biotin may facilitate delivery of dendrimers through the blood-brain barrier (BBB) via carrier-mediated endocytosis. The purpose of this research was to: (1) measure toxicity using lactate dehydrogenase (LDH) assays of generation (G)4 biotinylated and non-biotinylated poly(amidoamine) (PAMAM) dendrimers in a co-culture model of the BBB, (2) determine distribution of dendrimers in the rat brain, kidney, and liver following systemic administration of dendrimers, and (3) conduct atomic force microscopy (AFM) on rat brain sections following systemic administration of dendrimers. LDH measurements showed that biotinylated dendrimers were toxic to cell co-culture after 48 h of treatment. Distribution studies showed evidence of biotinylated and non-biotinylated PAMAM dendrimers in brain. AFM studies showed evidence of dendrimers only in brain tissue of treated rats. These results indicate that biotinylation does not decrease toxicity associated with PAMAM dendrimers and that biotinylated PAMAM dendrimers distribute in the brain. Furthermore, this article provides evidence of nanoparticles in brain tissue following systemic administration of nanoparticles supported by both fluorescence microscopy and AFM. Full article
(This article belongs to the Special Issue Dendrimers in Medicine and Biotechnology)
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Open AccessArticle Effect of Tomato Industrial Processing on Phenolic Profile and Antiplatelet Activity
Molecules 2013, 18(9), 11526-11536; https://doi.org/10.3390/molecules180911526
Received: 8 August 2013 / Revised: 12 September 2013 / Accepted: 12 September 2013 / Published: 17 September 2013
Cited by 16 | PDF Full-text (915 KB) | HTML Full-text | XML Full-text
Abstract
Background: Regular consumption of fruits and vegetables (e.g., tomatoes) has been shown to be beneficial in terms of reducing the incidence of cardiovascular diseases. The industrial processing of tomatoes into tomato-based products includes several thermal treatments. Very little is known on the
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Background: Regular consumption of fruits and vegetables (e.g., tomatoes) has been shown to be beneficial in terms of reducing the incidence of cardiovascular diseases. The industrial processing of tomatoes into tomato-based products includes several thermal treatments. Very little is known on the effect of tomato industrial processing on antiaggregatory activity and phenolic profile. Methods: It was assessed the effect of tomato and by-products extracts on platelet aggregation induced by ADP, collagen, TRAP-6 and arachidonic acid. These in vitro antithrombotic properties were further supported in an in vivo model of thrombosis. A set of antiplatelet compounds has been selected for HPLC analysis in the different extracts. Results: Some natural compounds such as chlorogenic, caffeic, ferulic and p-coumaric acids were identified by HPLC in tomatoes and its products may inhibit platelet activation. Red tomatoes, tomato products (sauce, ketchup and juice) and by-products extracts inhibited platelet aggregation induced adenosine 5'-diphosphate, collagen, thrombin receptor activator peptide-6 and arachidonic acid, but to a different extent. Also, pomace extract presents antithrombotic activity. Conclusions: Processed tomatoes may have a higher content of health-benefiting compounds than fresh ones. Pomace even presents the best antiplatelet activity. Finally, tomato products may be used as a functional ingredient adding antiplatelet activities to processed foods. Full article
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Open AccessArticle Click Reactions as a Key Step for an Efficient and Selective Synthesis of D-Xylose-Based ILs
Molecules 2013, 18(9), 11512-11525; https://doi.org/10.3390/molecules180911512
Received: 27 June 2013 / Revised: 7 August 2013 / Accepted: 10 September 2013 / Published: 17 September 2013
Cited by 7 | PDF Full-text (456 KB) | HTML Full-text | XML Full-text
Abstract
D-Xylose-based ionic liquids have been prepared from D-xylose following a five steps reaction sequence, the key step being a click cycloaddition. These ionic liquids (ILs) have been characterized through classical analytical methods (IR, NMR, mass spectroscopy, elemental analysis) and their stability constants, Tg
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D-Xylose-based ionic liquids have been prepared from D-xylose following a five steps reaction sequence, the key step being a click cycloaddition. These ionic liquids (ILs) have been characterized through classical analytical methods (IR, NMR, mass spectroscopy, elemental analysis) and their stability constants, Tg and Tdec, were also determined. Considering their properties and their hydrophilicity, these compounds could be alternative solvents for chemical applications under mild conditions. Full article
(This article belongs to the collection Advances in Click Chemistry)
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Open AccessArticle Synthesis and Biological Evaluation of Apigenin Derivatives as Antibacterial and Antiproliferative Agents
Molecules 2013, 18(9), 11496-11511; https://doi.org/10.3390/molecules180911496
Received: 8 July 2013 / Revised: 2 September 2013 / Accepted: 12 September 2013 / Published: 17 September 2013
Cited by 15 | PDF Full-text (266 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two series of apigenin [5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one] derivatives, 3a3j and 4a4j, were synthesized. The apigenin and alkyl amines moieties of these compounds were separated by C2 or C3 spacers, respectively. The chemical structures of the apigenin derivatives were
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Two series of apigenin [5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one] derivatives, 3a3j and 4a4j, were synthesized. The apigenin and alkyl amines moieties of these compounds were separated by C2 or C3 spacers, respectively. The chemical structures of the apigenin derivatives were confirmed using 1H-NMR, 13C-NMR, and electrospray ionization mass spectroscopy. The in vitro antibacterial and antiproliferative activities of all synthesized compounds were determined. Among the tested compounds, 4a4j displayed significant antibacterial activity against the tested strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa). Additionally, 4i showed the best inhibitory activity with minimum inhibitory concentrations of 1.95, 3.91, 3.91, and 3.91 μg/mL against S. aureus, B. subtilis, E. coli, and P. aeruginosa, respectively. The antiproliferative activity of the apigenin derivatives was evaluated by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. We determined that 4a4j displayed better growth inhibition activity against four human cancer cell lines, namely, human lung (A549), human cervical (HeLa), human hepatocellular liver (HepG2), and human breast (MCF-7) cancer cells, than the parent apigenin. Compound 4j was found to be the most active antiproliferative compound against the selected cancer cells. Structure-activity relationships were also discussed based on the obtained experimental data. Full article
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Open AccessArticle Fremy’s Salt-Mediated Oxidative Addition. A New Approach in the Total Synthesis of Naturally Dipetalolactone and Its Immunomodulatory Activity
Molecules 2013, 18(9), 11485-11495; https://doi.org/10.3390/molecules180911485
Received: 2 July 2013 / Revised: 30 July 2013 / Accepted: 26 August 2013 / Published: 16 September 2013
Cited by 1 | PDF Full-text (250 KB) | HTML Full-text | XML Full-text
Abstract
The structure of the natural dipyranocoumarin dipetalolactone has been confirmed by an unambiguous synthetic route from resorcinol. This sequence was initiated by a pyran ring formation step which introduced the 3-chloro-3-methylbut-1-yne moiety. Then, the expected product undergoes a Fremy’s salt-meditated oxidative addition followed
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The structure of the natural dipyranocoumarin dipetalolactone has been confirmed by an unambiguous synthetic route from resorcinol. This sequence was initiated by a pyran ring formation step which introduced the 3-chloro-3-methylbut-1-yne moiety. Then, the expected product undergoes a Fremy’s salt-meditated oxidative addition followed by ring closure to yield dipetalolactone. Dipetalolactone was also found to have immunological activity in a mouse carcinoma S180-bearing mice cell line. Full article
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Open AccessArticle Probing the Residual Structure in Avian Prion Hexarepeats by CD, NMR and MD Techniques
Molecules 2013, 18(9), 11467-11484; https://doi.org/10.3390/molecules180911467
Received: 5 August 2013 / Revised: 3 September 2013 / Accepted: 9 September 2013 / Published: 16 September 2013
Cited by 2 | PDF Full-text (907 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Many proteins perform essential biological functions by means of regions that lacking specific organized structure exist as an ensemble of interconverting transient conformers. The characterization of such regions, including the description of their structural propensities, number of conformations and relative populations can provide
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Many proteins perform essential biological functions by means of regions that lacking specific organized structure exist as an ensemble of interconverting transient conformers. The characterization of such regions, including the description of their structural propensities, number of conformations and relative populations can provide useful insights. Prion diseases result from the conversion of a normal glycoprotein into a misfolded pathogenic isoform. The structures of mammal and chicken prion proteins show a similar fold with a globular domain and a flexible N-terminal portion that contains different repeated regions: octarepeats (PHGGGWGQ) in mammals and hexarepeats (PHNPGY) in chickens. The higher number of prolines in the hexarepeat region suggests that this region may retain a significant amount of residual secondary structure. Here, we report the CD, NMR and MD characterization of a peptide (2-HexaPY) composed of two hexarepeats. We combine experimental NMR data and MD to investigate at atomic level its ensemble-averaged structural properties, demonstrating how each residue of both repeats has a different quantified PPII propensity that shows a periodicity along the sequence. This feature explains the absence of cooperativity to stabilize a PPII conformation. Nonetheless, such residual structure can play a role in nucleating local structural transitions as well as modulating intra-molecular or inter-molecular interactions. Full article
(This article belongs to the Special Issue NMR of Proteins and Small Biomolecules)
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Open AccessArticle Determination and Pharmacokinetics of Di-(2-ethylhexyl) Phthalate in Rats by Ultra Performance Liquid Chromatography with Tandem Mass Spectrometry
Molecules 2013, 18(9), 11452-11466; https://doi.org/10.3390/molecules180911452
Received: 22 July 2013 / Revised: 1 September 2013 / Accepted: 13 September 2013 / Published: 16 September 2013
Cited by 5 | PDF Full-text (1235 KB) | HTML Full-text | XML Full-text
Abstract
Di-(2-ethylhexyl) phthalate (DEHP) is used to increase the flexibility of plastics for industrial products. However, the illegal use of the plasticizer DEHP in food and drinks has been reported in Taiwan in 2011. In order to assess the exact extent of the absorption
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Di-(2-ethylhexyl) phthalate (DEHP) is used to increase the flexibility of plastics for industrial products. However, the illegal use of the plasticizer DEHP in food and drinks has been reported in Taiwan in 2011. In order to assess the exact extent of the absorption of DEHP via the oral route, the aim of this study is to develop a reliable and validated ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method to evaluate the oral bioavailability of DEHP in rats. The optimal chromatographic separation of DEHP and butyl benzyl phthalate (BBP; used as internal standard) were achieved on a C18 column. The mobile phase was consisted of 5 mM ammonium acetate-methanol (11:89, v/v) with a flow rate of 0.25 mL/min. The monitoring ion transitions were m/z 391.4 → 149.0 for DEHP and m/z 313.3 → 149.0 for BBP. The mean matrix effects of DEHP at low, medium and high concentrations were 94.5 ± 5.7% and 100.1 ± 2.3% in plasma and feces homogenate samples, respectively. In conclusion, the validated UPLC-MS/MS method is suitable for analyzing the rat plasma sample of DEHP and the oral bioavailability of DEHP was about 7% in rats. Full article
(This article belongs to the Section Metabolites)
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Open AccessArticle Harvestman Phenols and Benzoquinones: Characterisation and Biosynthetic Pathway
Molecules 2013, 18(9), 11429-11451; https://doi.org/10.3390/molecules180911429
Received: 19 July 2013 / Revised: 5 September 2013 / Accepted: 6 September 2013 / Published: 16 September 2013
Cited by 16 | PDF Full-text (1006 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Benzoquinones are usually present in arthropod defence exudates. Here, we describe the chemical profiles of 12 harvestman species belonging to the neotropical family Gonyleptidae. Nine of the studied species produced benzoquinones, while three produced alkyl phenols. Two benzoquinones and one phenol exhibited biological
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Benzoquinones are usually present in arthropod defence exudates. Here, we describe the chemical profiles of 12 harvestman species belonging to the neotropical family Gonyleptidae. Nine of the studied species produced benzoquinones, while three produced alkyl phenols. Two benzoquinones and one phenol exhibited biological activity against bacteria and fungi. We also studied the biosynthesis of 2-ethyl-1,4-benzoquinone by feeding Magnispina neptunus individuals with 13C-labelled precursors; the benzoquinones were biosynthesised through a polyketide pathway using acetate and propionate building blocks. Full article
(This article belongs to the Section Natural Products Chemistry)
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