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Molecules, Volume 17, Issue 4 (April 2012), Pages 3599-4769

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Open AccessReview Dynamic Action of Carotenoids in Cardioprotection and Maintenance of Cardiac Health
Molecules 2012, 17(4), 4755-4769; https://doi.org/10.3390/molecules17044755
Received: 6 February 2012 / Revised: 28 March 2012 / Accepted: 5 April 2012 / Published: 23 April 2012
Cited by 28 | PDF Full-text (339 KB) | HTML Full-text | XML Full-textRetraction
Abstract
Oxidative stress has been considered universally and undeniably implicated in the pathogenesis of all major diseases, including those of the cardiovascular system. Oxidative stress activate transcriptional messengers, such as nuclear factor—κB, tangibly contributing to endothelial dysfunction, the initiation and progression of atherosclerosis, irreversible
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Oxidative stress has been considered universally and undeniably implicated in the pathogenesis of all major diseases, including those of the cardiovascular system. Oxidative stress activate transcriptional messengers, such as nuclear factor—κB, tangibly contributing to endothelial dysfunction, the initiation and progression of atherosclerosis, irreversible damage after ischemic reperfusion, and even arrhythmia, such as atrial fibrillation. Evidence is rapidly accumulating to support the role of reactive oxygen species (ROS) and reactive nitrogen species (RNS) as intracellular signaling molecules. Despite this connection between oxidative stress and cardiovascular disease (CVD), there are currently no recognized therapeutic interventions to address this important unmet need. Antioxidants that provide a broad, “upstream” approach via ROS/RNS quenching or free radical chain breaking seem an appropriate therapeutic option based on epidemiologic, dietary, and in vivo animal model data. Short-term dietary intervention trials suggest that diets rich in fruit and vegetable intake lead to improvements in coronary risk factors and reduce cardiovascular mortality. Carotenoids are such abundant, plant-derived, fat-soluble pigments that functions as antioxidants. They are stored in the liver or adipose tissue, and are lipid soluble by becoming incorporated into plasma lipoprotein particles during transport. For these reasons, carotenoids may represent one plausible mechanism by which fruits and vegetables reduce the risk of chronic diseases as cardiovascular disease (CVD). This review paper outlines the role of carotenoids in maintaining cardiac health and cardioprotection mediated by several mechanisms including redox signaling. Full article
(This article belongs to the Special Issue Carotenoids)
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Open AccessArticle Simultaneous Determination of Salidroside and Its Aglycone Metabolite p-Tyrosol in Rat Plasma by Liquid Chromatography-Tandem Mass Spectrometry
Molecules 2012, 17(4), 4733-4754; https://doi.org/10.3390/molecules17044733
Received: 17 January 2012 / Revised: 3 April 2012 / Accepted: 13 April 2012 / Published: 23 April 2012
Cited by 19 | PDF Full-text (420 KB) | HTML Full-text | XML Full-text
Abstract
Salidroside and its aglycone p-tyrosol are two major phenols in the genus Rhodiola and have been confirmed to possess various pharmacological properties. In our present study, p-tyrosol was identified as the deglycosylation metabolite of salidroside after intravenous (i.v.) administration to rats
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Salidroside and its aglycone p-tyrosol are two major phenols in the genus Rhodiola and have been confirmed to possess various pharmacological properties. In our present study, p-tyrosol was identified as the deglycosylation metabolite of salidroside after intravenous (i.v.) administration to rats at a dose of 50 mg/kg, but was not detectable after intragastric gavage (i.g.) administration through HPLC-photodiode array detection (PDA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Next, an accurate and precise LC-MS/MS method was developed to quantitatively determine salidroside and p-tyrosol in rat plasma samples. Samples were analyzed by LC-MS/MS on a reverse-phase xTerra MS C18 column which was equilibrated and eluted with an isocratic mixture of acetonitrile-water (1:9, v/v) at a flow rate of 0.3 mL/min. The analytes were monitored by multiple reaction monitoring (MRM) under the negative electrospray ionization mode. The precursor/product transitions (m/z) were 299.0→118.8 for salidroside, 137.0→118.9 for p-tyrosol and 150.1→106.9 for the internal standard (IS), paracetamol, respectively. The calibration curve was linear over the concentration ranges of 50–2,000 ng/mL for salidroside and 20–200 ng/mL for p-tyrosol. The inter- and intra-day accuracy and precision were within ±15%. The method has been successfully applied to the pharmacokinetic study and the oral bioavailability was calculated. Full article
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Open AccessArticle Synthesis, Molecular Docking and Preliminary in-Vitro Cytotoxic Evaluation of Some Substituted Tetrahydro-naphthalene (2',3',4',6'-Tetra-O-Acetyl-β-D-Gluco/-Galactopyranosyl) Derivatives
Molecules 2012, 17(4), 4717-4732; https://doi.org/10.3390/molecules17044717
Received: 14 February 2012 / Revised: 9 April 2012 / Accepted: 13 April 2012 / Published: 23 April 2012
Cited by 6 | PDF Full-text (549 KB) | HTML Full-text | XML Full-text
Abstract
A facile, convenient and high yielding synthesis of novel S-glycosides and N-glycosides incorporating 1,2,3,4-tetrahydronaphthalene and or 1,2-dihydropyridines moieties has been described. The aglycons 2, 4, and 7 were coupled with different activated halosugars in the presence of basic and
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A facile, convenient and high yielding synthesis of novel S-glycosides and N-glycosides incorporating 1,2,3,4-tetrahydronaphthalene and or 1,2-dihydropyridines moieties has been described. The aglycons 2, 4, and 7 were coupled with different activated halosugars in the presence of basic and acidic medium. The preliminary in-vitro cytotoxic evaluation revealed that compounds 3c, 3f, 5c and 7b show promising activity. A molecular docking study was performed against tyrosine kinase (TK) (PDB code: 1t46) by Autodock Vina. The docking output was analyzed and some compounds have shown hydrogen bond (H-B) formation with reasonable distances ranged from 2.06 A° to 3.06 A° with Thr 670 and Cys 673 residues found in the specified pocket. No hydrogen bond was observed with either Glu 640 nor Asp 810 residues, as was expected from pdbsum. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Synthesis and Cytotoxic Activity of Some Novel N-Pyridinyl-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide Derivatives
Molecules 2012, 17(4), 4703-4716; https://doi.org/10.3390/molecules17044703
Received: 29 February 2012 / Revised: 1 April 2012 / Accepted: 13 April 2012 / Published: 23 April 2012
Cited by 17 | PDF Full-text (242 KB) | HTML Full-text | XML Full-text
Abstract
A series of novel compounds bearing imidazo[2,1-b]thiazole scaffolds were designed and synthesized based on the optimization of the virtual screening hit compound N-(6-morpholinopyridin-3-yl)-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide (5a), and tested for their cytotoxicity against human cancer cell lines, including HepG2 and MDA-MB-231.
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A series of novel compounds bearing imidazo[2,1-b]thiazole scaffolds were designed and synthesized based on the optimization of the virtual screening hit compound N-(6-morpholinopyridin-3-yl)-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide (5a), and tested for their cytotoxicity against human cancer cell lines, including HepG2 and MDA-MB-231. The results indicated that the compound 2-(6-(4-chlorophenyl)imidazo[2,1-b]thiazol-3-yl)-N-(6-(4-(4-methoxybenzyl)piperazin-1-yl)pyridin-3-yl)acetamide (5l), with slightly higher inhibition on VEGFR2 than 5a (5.72% and 3.76% inhibitory rate at 20 μM, respectively), was a potential inhibitor against MDA-MB-231 (IC50 = 1.4 μM) compared with sorafenib (IC50 = 5.2 μM), and showed more selectivity against MDA-MB-231 than HepG2 cell line (IC50 = 22.6 μM). Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Self-Organizing Maps of Molecular Descriptors for Sesquiterpene Lactones and Their Application to the Chemotaxonomy of the Asteraceae Family
Molecules 2012, 17(4), 4684-4702; https://doi.org/10.3390/molecules17044684
Received: 26 March 2012 / Revised: 11 April 2012 / Accepted: 12 April 2012 / Published: 20 April 2012
Cited by 21 | PDF Full-text (355 KB) | HTML Full-text | XML Full-text
Abstract
The Asteraceae, one of the largest families among angiosperms, is chemically characterised by the production of sesquiterpene lactones (SLs). A total of 1,111 SLs, which were extracted from 658 species, 161 genera, 63 subtribes and 15 tribes of Asteraceae, were represented and registered
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The Asteraceae, one of the largest families among angiosperms, is chemically characterised by the production of sesquiterpene lactones (SLs). A total of 1,111 SLs, which were extracted from 658 species, 161 genera, 63 subtribes and 15 tribes of Asteraceae, were represented and registered in two dimensions in the SISTEMATX, an in-house software system, and were associated with their botanical sources. The respective 11 block of descriptors: Constitutional, Functional groups, BCUT, Atom-centred, 2D autocorrelations, Topological, Geometrical, RDF, 3D-MoRSE, GETAWAY and WHIM were used as input data to separate the botanical occurrences through self-organising maps. Maps that were generated with each descriptor divided the Asteraceae tribes, with total index values between 66.7% and 83.6%. The analysis of the results shows evident similarities among the Heliantheae, Helenieae and Eupatorieae tribes as well as between the Anthemideae and Inuleae tribes. Those observations are in agreement with systematic classifications that were proposed by Bremer, which use mainly morphological and molecular data, therefore chemical markers partially corroborate with these classifications. The results demonstrate that the atom-centred and RDF descriptors can be used as a tool for taxonomic classification in low hierarchical levels, such as tribes. Descriptors obtained through fragments or by the two-dimensional representation of the SL structures were sufficient to obtain significant results, and better results were not achieved by using descriptors derived from three-dimensional representations of SLs. Such models based on physico-chemical properties can project new design SLs, similar structures from literature or even unreported structures in two-dimensional chemical space. Therefore, the generated SOMs can predict the most probable tribe where a biologically active molecule can be found according Bremer classification. Full article
(This article belongs to the Special Issue Terpenoids)
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Open AccessArticle Effect of Paeonol on Antioxidant and Immune Regulatory Activity in Hepatocellular Carcinoma Rats
Molecules 2012, 17(4), 4672-4683; https://doi.org/10.3390/molecules17044672
Received: 8 March 2012 / Revised: 27 March 2012 / Accepted: 5 April 2012 / Published: 20 April 2012
Cited by 44 | PDF Full-text (196 KB) | HTML Full-text | XML Full-text
Abstract
The study investigated the immunity and antioxidant potential of paeonol by employing a hepatocellular carcinoma (HCC) rat model. Three doses of paeonol (20, 40, 60 mg/kg b.w. orally) were administrated to diethylnitrosamine (DEN)-induced HCC rats. Results showed that paeonol significantly reduced the serum
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The study investigated the immunity and antioxidant potential of paeonol by employing a hepatocellular carcinoma (HCC) rat model. Three doses of paeonol (20, 40, 60 mg/kg b.w. orally) were administrated to diethylnitrosamine (DEN)-induced HCC rats. Results showed that paeonol significantly reduced the serum AST, ALT, ALP, GGT, AFU and liver MDA levels, increased serum WBC, TP, ALB, A/G, TNF-α and IFN-γ and liver antioxidant enzymes activities (SOD, CAT, GSH-Px, GR) in HCC rats. Altogether, these results suggest that the paeonol could effectively decrease oxidative injury and improve immunity function in HCC rats. Full article
Open AccessArticle The Rotational Barrier in Ethane: A Molecular Orbital Study
Molecules 2012, 17(4), 4661-4671; https://doi.org/10.3390/molecules17044661
Received: 27 March 2012 / Revised: 12 April 2012 / Accepted: 12 April 2012 / Published: 20 April 2012
Cited by 8 | PDF Full-text (296 KB) | HTML Full-text | XML Full-text
Abstract
The energy change on each Occupied Molecular Orbital as a function of rotation about the C-C bond in ethane was studied using the B3LYP, mPWB95 functional and MP2 methods with different basis sets.Also, the effect of the ZPE on rotational barrier was analyzed.
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The energy change on each Occupied Molecular Orbital as a function of rotation about the C-C bond in ethane was studied using the B3LYP, mPWB95 functional and MP2 methods with different basis sets.Also, the effect of the ZPE on rotational barrier was analyzed. We have found that σ and π energies contribution stabilize a staggered conformation. The σs molecular orbital stabilizes the staggered conformation while the stabilizes the eclipsed conformation and destabilize the staggered conformation. The πz and molecular orbitals stabilize both the eclipsed and staggered conformations, which are destabilized by the πv and molecular orbitals. The results show that the method of calculation has the effect of changing the behavior of the energy change in each Occupied Molecular Orbital energy as a function of the angle of rotation about the C–C bond in ethane. Finally, we found that if the molecular orbital energy contribution is deleted from the rotational energy, an inversion in conformational preference occurs. Full article
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Open AccessArticle Anti-Tumour Promoting Activity and Antioxidant Properties of Girinimbine Isolated from the Stem Bark of Murraya koenigii S.
Molecules 2012, 17(4), 4651-4660; https://doi.org/10.3390/molecules17044651
Received: 26 December 2011 / Revised: 5 April 2012 / Accepted: 11 April 2012 / Published: 20 April 2012
Cited by 18 | PDF Full-text (370 KB) | HTML Full-text | XML Full-text
Abstract
Girinimbine, a carbazole alkaloid isolated from the stem bark of Murraya koenigii was tested for the in vitro anti-tumour promoting and antioxidant activities. Anti-tumour promoting activity was determined by assaying the capability of this compound to inhibit the expression of early antigen of
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Girinimbine, a carbazole alkaloid isolated from the stem bark of Murraya koenigii was tested for the in vitro anti-tumour promoting and antioxidant activities. Anti-tumour promoting activity was determined by assaying the capability of this compound to inhibit the expression of early antigen of Epstein-Barr virus (EA-EBV) in Raji cells that was induced by the tumour promoter, phorbol 12-myristate 13-acetate. The concentration of this compound that gave an inhibition rate at fifty percent was 6.0 µg/mL and was not cytotoxic to the cells. Immunoblotting analysis of the expression of EA-EBV showed that girinimbine was able to suppress restricted early antigen (EA-R). However, diffused early antigen (EA-D) was partially suppressed when used at 32.0 µg/mL. Girinimbine exhibited a very strong antioxidant activity as compared to a-tocopherol and was able to inhibit superoxide generation in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced differentiated premyelocytic HL-60 cells more than 95%, when treated with the compound at 5.3 and 26.3 µg/mL, respectively. However girinimbine failed to scavenge the stable diphenyl picryl hydrazyl (DPPH)-free radical. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Synthesis and Antibacterial Evaluation of New N-acylhydrazone Derivatives from Dehydroabietic Acid
Molecules 2012, 17(4), 4634-4650; https://doi.org/10.3390/molecules17044634
Received: 26 March 2012 / Revised: 1 April 2012 / Accepted: 5 April 2012 / Published: 20 April 2012
Cited by 20 | PDF Full-text (313 KB) | HTML Full-text | XML Full-text
Abstract
A series of new N-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR, ESI-MS, elemental analysis
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A series of new N-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR, ESI-MS, elemental analysis and single crystal X-ray diffraction. From the crystal structure of compound 4l, the C=N double bonds of these N-acylhydrazones showed (E)-configuration, while the NMR data of compounds 4aq indicated the existence of two rotamers for each compound in solution. The target compounds were evaluated for their antibacterial activities against four microbial strains. The result suggested that several compounds exhibited pronounced antibacterial activities. Particularly, compound 4p exhibited good antibacterial activity against Staphylococcus aureus and Bacillus subtilis comparable to positive control. The possible antibacterial metabolism and the strategy for further optimization of this compound were also discussed. Full article
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Open AccessArticle An Improved Synthesis of Pentacene: Rapid Access to a Benchmark Organic Semiconductor
Molecules 2012, 17(4), 4625-4633; https://doi.org/10.3390/molecules17044625
Received: 20 March 2012 / Revised: 6 April 2012 / Accepted: 6 April 2012 / Published: 20 April 2012
Cited by 16 | PDF Full-text (285 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Pentacene is an organic semiconductor used in a variety of thin-film organic electronic devices. Although at least six separate syntheses of pentacene are known (two from dihydropentacenes, two from 6,13-pentacenedione and two from 6,13-dihydro-6,13-dihydroxypentacene), none is ideal and several utilize elevated temperatures that
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Pentacene is an organic semiconductor used in a variety of thin-film organic electronic devices. Although at least six separate syntheses of pentacene are known (two from dihydropentacenes, two from 6,13-pentacenedione and two from 6,13-dihydro-6,13-dihydroxypentacene), none is ideal and several utilize elevated temperatures that may facilitate the oxidation of pentacene as it is produced. Here, we present a fast (~2 min of reaction time), simple, high-yielding (≥90%), low temperature synthesis of pentacene from readily available 6,13-dihydro-6,13-dihydroxypentacene. Further, we discuss the mechanism of this highly efficient reaction. With this improved synthesis, researchers gain rapid, affordable access to high purity pentacene in excellent yield and without the need for a time consuming sublimation. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Hydrogel of Ketoconazole and PAMAM Dendrimers: Formulation and Antifungal Activity
Molecules 2012, 17(4), 4612-4624; https://doi.org/10.3390/molecules17044612
Received: 21 February 2012 / Revised: 30 March 2012 / Accepted: 9 April 2012 / Published: 18 April 2012
Cited by 24 | PDF Full-text (262 KB) | HTML Full-text | XML Full-text
Abstract
Ketoconazole (KET), an imidazole derivative with well-known antifungal properties, is lipophilic and practically insoluble in water, therefore its clinical use has some practical disadvantages. The aim of the present study was to investigate the influence of PAMAM-NH2 and PAMAM-OH dendrimers generation 2
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Ketoconazole (KET), an imidazole derivative with well-known antifungal properties, is lipophilic and practically insoluble in water, therefore its clinical use has some practical disadvantages. The aim of the present study was to investigate the influence of PAMAM-NH2 and PAMAM-OH dendrimers generation 2 and generation 3 on the solubility and antifungal activity of KET and to design and evaluate KET hydrogel with PAMAM dendrimers. It was shown that the surface charge of PAMAM dendrimers strongly affects their influence on the improvement of solubility and antifungal activity of KET. The MIC and MFC values obtained by broth dilution method indicate that PAMAM-NH2 dendrimers significantly (up to 16-fold) increased the antifungal activity of KET against Candida strains (e.g., in culture Candida albicans 1103059/11 MIC value was 0.008 μg/mL and 0.064 μg/mL, and MFC was 2 μg/mL and 32 μg/mL for KET in 10 mg/mL solution of PAMAM-NH2 G2 and pure KET, respectively). Antifungal activity of designed KET hydrogel with PAMAM-NH2 dendrimers measured by the plate diffusion method was definitely higher than pure KET hydrogel and than commercial available product. It was shown that the improvement of solubility and in the consequence the higher KET release from hydrogels seems to be a very significant factor affecting antifungal activity of KET in hydrogels containing PAMAM dendrimers. Full article
(This article belongs to the Special Issue Dendrimers - from Synthesis to Applications)
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Open AccessArticle Extraction and Characterization of Chitin from the Beetle Holotrichia parallela Motschulsky
Molecules 2012, 17(4), 4604-4611; https://doi.org/10.3390/molecules17044604
Received: 6 March 2012 / Revised: 31 March 2012 / Accepted: 11 April 2012 / Published: 17 April 2012
Cited by 85 | PDF Full-text (2239 KB) | HTML Full-text | XML Full-text
Abstract
Insect chitin was isolated from adult Holotrichia parallela by treatment with 1 M HCl and 1 M NaOH, following by 1% potassium permanganate solution for decolorization. The yield of chitin from this species is 15%. This insect chitin was compared with the commercial
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Insect chitin was isolated from adult Holotrichia parallela by treatment with 1 M HCl and 1 M NaOH, following by 1% potassium permanganate solution for decolorization. The yield of chitin from this species is 15%. This insect chitin was compared with the commercial a-chitin from shrimp, by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. Both chitins exhibited similar chemical structures and physicochemical properties. Adult H. parallela is thus a promising alternative source of chitin. Full article
(This article belongs to the Special Issue Natural Polysaccharides: Chemistry, Bioactivity and Analysis)
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Open AccessArticle A New Isorhamnetin Glycoside and Other Phenolic Compounds from Callianthemum taipaicum
Molecules 2012, 17(4), 4595-4603; https://doi.org/10.3390/molecules17044595
Received: 2 December 2011 / Revised: 3 April 2012 / Accepted: 6 April 2012 / Published: 17 April 2012
Cited by 25 | PDF Full-text (219 KB) | HTML Full-text | XML Full-text
Abstract
A new flavonol glycoside together with five known phenolic compounds were isolated from the whole herb of Callianthemum taipaicum. The compounds were identified as isorhamnetin-3-O-α-L-arabinoside-7-O-β-D-glucoside (1), isorhamnetin-3-O-β-D-glucoside (2), dibutyl phthalate (3
[...] Read more.
A new flavonol glycoside together with five known phenolic compounds were isolated from the whole herb of Callianthemum taipaicum. The compounds were identified as isorhamnetin-3-O-α-L-arabinoside-7-O-β-D-glucoside (1), isorhamnetin-3-O-β-D-glucoside (2), dibutyl phthalate (3), (+)-1-hydroxylpinoresinol-4'-β-D-glucoside (4), pinoresinol-4'-O-β-D-glucoside (5) and 2-phenylethyl-β-primeveroside (6). Compound 1 was identified as a new flavonol glycoside. The compound 6 was isolated for the first time as natural product. All compounds were isolated for the first time from the Callianthemum genus. Furthermore, the 2D-NMR data of the four known compounds 2–5 are given for the first time in this paper. All the structures were identified on the basis of detailed spectral analysis. The compounds 1 and 4 exhibited certain antifungal activity. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Isolation and Identification of Myo-Inositol Crystals from Dragon Fruit (Hylocereus polyrhizus)
Molecules 2012, 17(4), 4583-4594; https://doi.org/10.3390/molecules17044583
Received: 1 March 2012 / Revised: 5 April 2012 / Accepted: 6 April 2012 / Published: 17 April 2012
Cited by 7 | PDF Full-text (506 KB) | HTML Full-text | XML Full-text
Abstract
Crystals isolated from Hylocereus polyrhizus were analyzed using four different approaches—X-ray Crystallography, High Performance Liquid Chromatography (HPLC), Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Nuclear Magnetic Resonance (NMR) and identified as myo-inositol. The X-ray crystallography analysis showed that the unit-cell parameters were:
[...] Read more.
Crystals isolated from Hylocereus polyrhizus were analyzed using four different approaches—X-ray Crystallography, High Performance Liquid Chromatography (HPLC), Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and Nuclear Magnetic Resonance (NMR) and identified as myo-inositol. The X-ray crystallography analysis showed that the unit-cell parameters were: a = 6.6226 (3) Å, b = 12.0462 (5) Å, c = 18.8942 (8) Å, α = 90.00, β = 93.98, δ = 90.00. The purity of the crystals were checked using HPLC, whereupon a clean single peak was obtained at 4.8 min with a peak area of 41232 μV*s. The LC-MS/MS technique, which is highly sensitive and selective, was used to provide a comparison of the isolated crystals with a myo-inositol standard where the results gave an identical match for both precursor and product ions. NMR was employed to confirm the molecular structure and conformation of the crystals, and the results were in agreement with the earlier results in this study. The discovery of myo-inositol crystals in substantial amount in H. polyrhizus has thus far not been reported and this is an important finding which will increase the marketability and importance of H. polyrhizus as a crop with a wide array of health properties. Full article
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Open AccessArticle A Support Vector Machine Classification Model for Benzo[c]phenathridine Analogues with Topoisomerase-I Inhibitory Activity
Molecules 2012, 17(4), 4560-4582; https://doi.org/10.3390/molecules17044560
Received: 13 March 2012 / Revised: 8 April 2012 / Accepted: 10 April 2012 / Published: 17 April 2012
Cited by 4 | PDF Full-text (603 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Benzo[c]phenanthridine (BCP) derivatives were identified as topoisomerase I (TOP-I) targeting agents with pronounced antitumor activity. In this study, a support vector machine model was performed on a series of 73 analogues to classify BCP derivatives according to TOP-I inhibitory activity. The
[...] Read more.
Benzo[c]phenanthridine (BCP) derivatives were identified as topoisomerase I (TOP-I) targeting agents with pronounced antitumor activity. In this study, a support vector machine model was performed on a series of 73 analogues to classify BCP derivatives according to TOP-I inhibitory activity. The best SVM model with total accuracy of 93% for training set was achieved using a set of 7 descriptors identified from a large set via a random forest algorithm. Overall accuracy of up to 87% and a Matthews coefficient correlation (MCC) of 0.71 were obtained after this SVM classifier was validated internally by a test set of 15 compounds. For two external test sets, 89% and 80% BCP compounds, respectively, were correctly predicted. The results indicated that our SVM model could be used as the filter for designing new BCP compounds with higher TOP-I inhibitory activity. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Systematic Evaluation of Structure-Activity Relationships of the Riminophenazine Class and Discovery of a C2 Pyridylamino Series for the Treatment of Multidrug-Resistant Tuberculosis
Molecules 2012, 17(4), 4545-4559; https://doi.org/10.3390/molecules17044545
Received: 9 March 2012 / Revised: 9 April 2012 / Accepted: 10 April 2012 / Published: 17 April 2012
Cited by 9 | PDF Full-text (321 KB) | HTML Full-text | XML Full-text
Abstract
Clofazimine, a member of the riminophenazine class of drugs, is the cornerstone agent for the treatment of leprosy. This agent is currently being studied in clinical trials for the treatment of multidrug-resistant tuberculosis to address the urgent need for new drugs that can
[...] Read more.
Clofazimine, a member of the riminophenazine class of drugs, is the cornerstone agent for the treatment of leprosy. This agent is currently being studied in clinical trials for the treatment of multidrug-resistant tuberculosis to address the urgent need for new drugs that can overcome existing and emerging drug resistance. However, the use of clofazimine in tuberculosis treatment is hampered by its high lipophilicity and skin pigmentation side effects. To identify a new generation of riminophenazines that is less lipophilic and skin staining, while maintaining efficacy, we have performed a systematic structure-activity relationship (SAR) investigation by synthesizing a variety of analogs of clofazimine and evaluating their anti-tuberculosis activity. The study reveals that the central tricyclic phenazine system and the pendant aromatic rings are important for anti-tuberculosis activity. However, the phenyl groups attached to the C2 and N5 position of clofazimine can be replaced by a pyridyl group to provide analogs with improved physicochemical properties and pharmacokinetic characteristics. Replacement of the phenyl group attached to the C2 position by a pyridyl group has led to a promising new series of compounds with improved physicochemical properties, improved anti-tuberculosis potency, and reduced pigmentation potential. Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle Large-Scale Solvent-Free Chlorination of Hydroxy-Pyrimidines, -Pyridines, -Pyrazines and -Amides Using Equimolar POCl3
Molecules 2012, 17(4), 4533-4544; https://doi.org/10.3390/molecules17044533
Received: 7 March 2012 / Revised: 31 March 2012 / Accepted: 6 April 2012 / Published: 16 April 2012
Cited by 13 | PDF Full-text (232 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Chlorination with equimolar POCl3 can be efficiently achieved not only for hydroxypyrimidines, but also for many other substrates such as 2-hydroxy-pyridines, -quinoxalines, or even -amides. The procedure is solvent-free and involves heating in a sealed reactor at high temperatures using one equivalent
[...] Read more.
Chlorination with equimolar POCl3 can be efficiently achieved not only for hydroxypyrimidines, but also for many other substrates such as 2-hydroxy-pyridines, -quinoxalines, or even -amides. The procedure is solvent-free and involves heating in a sealed reactor at high temperatures using one equivalent of pyridine as base. It is suitable for large scale (multigram) batch preparations. Full article
(This article belongs to the Special Issue Solvent-Free Synthesis)
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Open AccessArticle Gene Cloning, Expression and Activity Analysis of Manganese Superoxide Dismutase from Two Strains of Gracilaria lemaneiformis (Gracilariaceae, Rhodophyta) under Heat Stress
Molecules 2012, 17(4), 4522-4532; https://doi.org/10.3390/molecules17044522
Received: 6 February 2012 / Revised: 22 March 2012 / Accepted: 4 April 2012 / Published: 16 April 2012
Cited by 10 | PDF Full-text (752 KB) | HTML Full-text | XML Full-text
Abstract
Manganese superoxide dismutase (Mn-SOD) plays a crucial role in antioxidant responses to environmental stress. To determine whether Mn-SOD affects heat resistance of Gracilaria lemaneiformis, we cloned Mn-SOD cDNA sequences of two strains of this red alga, wild type and cultivar 981. Both
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Manganese superoxide dismutase (Mn-SOD) plays a crucial role in antioxidant responses to environmental stress. To determine whether Mn-SOD affects heat resistance of Gracilaria lemaneiformis, we cloned Mn-SOD cDNA sequences of two strains of this red alga, wild type and cultivar 981. Both cDNA sequences contained an ORF of 675 bp encoding 224 amino acid residues. The cDNA sequences and the deduced amino acid sequences of the two strains shared relatively high identity (more than 99%). No intron existed in genomic DNA of Mn-SOD in G. lemaneiformis. Southern blotting indicated that there were multiple copies, possibly four, of Mn-SOD in both strains. Both in the wild type and cultivar 981, SOD mRNA transcription and SOD activity increased under high temperature stress, while cultivar 981 was more heat resistant based on its SOD activity. This research suggests that there may be a direct relationship between SOD activity and the heat resistance of G. lemaneiformis. Full article
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Open AccessArticle The Suzuki Reaction Applied to the Synthesis of Novel Pyrrolyl and Thiophenyl Indazoles
Molecules 2012, 17(4), 4508-4521; https://doi.org/10.3390/molecules17044508
Received: 20 February 2012 / Revised: 5 April 2012 / Accepted: 9 April 2012 / Published: 16 April 2012
Cited by 8 | PDF Full-text (267 KB) | HTML Full-text | XML Full-text
Abstract
The paper describes the Suzuki cross-coupling of a variety of N and C-3 substituted 5-bromoindazoles with N-Boc-2-pyrrole and 2-thiopheneboronic acids. The reactions, performed in the presence of K2CO3, dimethoxyethane and Pd(dppf)Cl2 as catalyst, gave the corresponding
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The paper describes the Suzuki cross-coupling of a variety of N and C-3 substituted 5-bromoindazoles with N-Boc-2-pyrrole and 2-thiopheneboronic acids. The reactions, performed in the presence of K2CO3, dimethoxyethane and Pd(dppf)Cl2 as catalyst, gave the corresponding adducts in good yields. The methodology allows the facile production of indazole-based heteroaryl compounds, a unique architectural motif that is ubiquitous in biologically active molecules. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Regioselectivity in the Ring Opening of Epoxides for the Synthesis of Aminocyclitols from D-(-)-Quinic Acid
Molecules 2012, 17(4), 4498-4507; https://doi.org/10.3390/molecules17044498
Received: 26 March 2012 / Revised: 9 April 2012 / Accepted: 10 April 2012 / Published: 16 April 2012
Cited by 7 | PDF Full-text (279 KB) | HTML Full-text | XML Full-text
Abstract
Efficient syntheses of four aminocyclitols are reported. Each synthesis is accomplished in eight steps starting from D-(-)-quinic acid. The key step involves a highly regioselective ring opening of epoxides by sodium azide. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Natural Chlorophyll-Related Porphyrins and Chlorins for Dye-Sensitized Solar Cells
Molecules 2012, 17(4), 4484-4497; https://doi.org/10.3390/molecules17044484
Received: 13 March 2012 / Revised: 5 April 2012 / Accepted: 6 April 2012 / Published: 13 April 2012
Cited by 32 | PDF Full-text (746 KB) | HTML Full-text | XML Full-text
Abstract
Natural-chlorophyll-related porphyrins, including (2H, Zn, Cu)-protoporphyrin IX (Por-1) and Zn-mesoporphyrin IX (Por-2), and chlorins, including chlorin e6 (Chl-1), chlorin e4 (Chl-2), and rhodin G7 (Chl-3), have been used in dye-sensitized solar cells (DSSCs). For porphyrin sensitizers that have vinyl groups
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Natural-chlorophyll-related porphyrins, including (2H, Zn, Cu)-protoporphyrin IX (Por-1) and Zn-mesoporphyrin IX (Por-2), and chlorins, including chlorin e6 (Chl-1), chlorin e4 (Chl-2), and rhodin G7 (Chl-3), have been used in dye-sensitized solar cells (DSSCs). For porphyrin sensitizers that have vinyl groups at the β-positions, zinc coordinated Por-1 gives the highest solar-energy-to-electricity conversion efficiency (h) of up to 2.9%. Replacing the vinyl groups of ZnPor-1 with ethyl groups increases the open-circuit voltage (Voc) from 0.61 V to 0.66 V, but decreases the short-circuit current (Jsc) from 7.0 mA·cm−2 to 6.1 mA·cm−2 and the value of h to 2.8%. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations suggest that the higher Jsc values of Zn-based porphyrin sensitizers result from the favorable electron injection from the LUMO at higher energy levels. In the case of the chlorin sensitizers, the number of carboxyl protons has a large effect on the photovoltaic performance. Chl-2 with two carboxyl protons gives much higher values of Jsc, Voc, and h than does Chl-1 with three carboxyl protons. Replacing the protons of Chl-1 with sodium ions can substantially improve the photovoltaic performance of Chl-1-based solar cells. Furthermore, the sodium salt of Chl-3 with an aldehyde group at the C7 position shows poorer photovoltaic performance than does the sodium salt of Chl-1 with methyl groups at the C7 position. This is due to the low light-harvesting capability of Chl-3. Full article
(This article belongs to the Special Issue Tetrapyrroles, Porphyrins and Phthalocyanines)
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Open AccessArticle Antiangiogenic Polyketides from Peperomia dindygulensis Miq.
Molecules 2012, 17(4), 4474-4483; https://doi.org/10.3390/molecules17044474
Received: 17 February 2012 / Revised: 5 April 2012 / Accepted: 6 April 2012 / Published: 13 April 2012
Cited by 13 | PDF Full-text (342 KB) | HTML Full-text | XML Full-text
Abstract
Two new polyketides: 2Z-(heptadec-12-enyl)-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (1) and 2-(heptadec-12-enyl)-5-hydroxy-5,6,7,8-tetrahydrochromen- 4-one (2), together with eleven known compounds: 4-hydroxy-2-[(3,4-methylenedioxy- phenyl)tridecanoyl] cyclohexane-1,3-dione (3), oleiferinone (4), 4-hydroxy-2-[(3,4- methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (5), 4-hydroxy-2-[(11-phenyl- undecanoyl)cyclohexane-1,3-dione (6
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Two new polyketides: 2Z-(heptadec-12-enyl)-4-hydroxy-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one (1) and 2-(heptadec-12-enyl)-5-hydroxy-5,6,7,8-tetrahydrochromen- 4-one (2), together with eleven known compounds: 4-hydroxy-2-[(3,4-methylenedioxy- phenyl)tridecanoyl] cyclohexane-1,3-dione (3), oleiferinone (4), 4-hydroxy-2-[(3,4- methylenedioxyphenyl)undecanoyl]cyclohexane-1,3-dione (5), 4-hydroxy-2-[(11-phenyl- undecanoyl)cyclohexane-1,3-dione (6), proctorione C (7), surinone C (8), 5-hydroxy- 7,8,4'-trimethoxyflavone (9), 5-hydroxy-7,8,3',4'-tetramethoxyflavone (10), 5-hydroxy- 7,3',4'-trimethoxyflavone (11), 5,8-dihydroxy-7,3',4'-trimethoxyflavone (12) and cepharanone B (13) were isolated from the whole plant of Peperomia dindygulensis Miq. Their structures were elucidated by spectroscopic methods, including 2D-NMR techniques. Compounds 2, 3, 5 and 8 inhibited human umbilical vein endothelial cell (HUVEC) proliferation and compounds 5 and 8 sharply suppressed HUVEC tube formation. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Synthesis of 2RS,4RS-1-[2-Phenyl-4-[2-(2-trifluromethoxy-phenoxy)-ethyl]-1,3-dioxolan-2-yl-methyl]-1H-1,2,4-triazole Derivatives as Potent Inhibitors of Brassinosteroid Biosynthesis
Molecules 2012, 17(4), 4460-4473; https://doi.org/10.3390/molecules17044460
Received: 21 February 2012 / Revised: 5 April 2012 / Accepted: 9 April 2012 / Published: 13 April 2012
Cited by 20 | PDF Full-text (571 KB) | HTML Full-text | XML Full-text
Abstract
Brassinosteroids are important phytohormones that affect many aspects of plant growth and development. In order to manipulate brassinosteroid levels in plant tissues by using specific biosynthesis inhibitors, we have carried out a systemic search for specific inhibitors of brassinosteroid biosynthesis. Synthesis of triazole
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Brassinosteroids are important phytohormones that affect many aspects of plant growth and development. In order to manipulate brassinosteroid levels in plant tissues by using specific biosynthesis inhibitors, we have carried out a systemic search for specific inhibitors of brassinosteroid biosynthesis. Synthesis of triazole derivatives based on the ketoconazole scaffold revealed a series of novel brassinosteroid biosynthesis inhibitors (the YCZ series). To explore the structure-activity relationships of this synthetic series, we now report the synthesis of new triazole derivatives with different aromatic structures at position 2 of 1,3-dioxolane skeleton. We found that the variation of aromatic substituent significantly affect the inhibitory potency. Structure-activity relationships studies indicated that 4-chlorophenyl analogue is the most potent inhibitor of BR biosynthesis with an IC50 value approximately 0.12 ± 0.04 µM, while a bulky biphenyl group exhibited a great negative effect on promoting the inhibitory potency with an IC50 larger than 10 µM. Full article
(This article belongs to the collection Bioactive Compounds)
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Open AccessCommunication Selective Formation of Twisted Intramolecular Charge Transfer and Excimer Emissions on 2,7-bis(4-Diethylaminophenyl)-fluorenone by Choice of Solvent
Molecules 2012, 17(4), 4452-4459; https://doi.org/10.3390/molecules17044452
Received: 1 March 2012 / Revised: 30 March 2012 / Accepted: 6 April 2012 / Published: 13 April 2012
Cited by 22 | PDF Full-text (284 KB) | Supplementary Files
Abstract
We designed and synthesized a donor-acceptor-donor dye consisting of a 2,7-disubstituted fluorenone with diethylaminophenyl moieties present as strong electron donating groups. Switching between twisted intramolecular charge transfer (TICT) emission and excimer emission was achieved, with no ground state changes, by simply changing the
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We designed and synthesized a donor-acceptor-donor dye consisting of a 2,7-disubstituted fluorenone with diethylaminophenyl moieties present as strong electron donating groups. Switching between twisted intramolecular charge transfer (TICT) emission and excimer emission was achieved, with no ground state changes, by simply changing the solvent used. In a nonpolar solvent, excimer emission was observed; with increasing polarity, the emission gradually disappeared, and the TICT emission appeared. Full article
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Open AccessArticle Investigation on the Protective Effects of Cranberry Against the DNA Damage Induced by Benzo[a]pyrene
Molecules 2012, 17(4), 4435-4451; https://doi.org/10.3390/molecules17044435
Received: 27 February 2012 / Revised: 19 March 2012 / Accepted: 20 March 2012 / Published: 12 April 2012
Cited by 7 | PDF Full-text (205 KB)
Abstract
There are few reports that demonstrate the antigenotoxic potential of cranberries. Although the types of berry fruits consumed worldwide are many, this paper focuses on cranberries that are commonly consumed in Mexico (Vaccinium macrocarpon species). The purpose of the present study is
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There are few reports that demonstrate the antigenotoxic potential of cranberries. Although the types of berry fruits consumed worldwide are many, this paper focuses on cranberries that are commonly consumed in Mexico (Vaccinium macrocarpon species). The purpose of the present study is to determine whether cranberry ethanolic extract (CEE) can prevent the DNA damage produced by benzo[a]pyrene (B[a]P) using an in vivo mouse peripheral blood micronucleus assay. The experimental groups were organized as follows: a negative control group (without treatment), a positive group treated with B[a]P (200 mg/kg), a group administered with 800 mg/kg of CEE, and three groups treated with B[a]P and CEE (200, 400, and 800 mg/kg) respectively. The CEE and benzo[a]pyrene were administered orally for a week, on a daily basis. During this period the body weight, the feed intake, and the determination of antigenotoxic potential were quantified. At the end of this period, we continued with the same determinations for one week more (recovery period) but anymore administration of the substances. The animals treated with B[a]P showed a weight increase after the first week of administration. The same phenomenon was observed in the lots combined with B[a]P and CEE (low and medium doses). The dose of 800 mg/kg of CEE showed similar values to the control group at the end of the treatment period. In the second part of the assay, when the substances were not administered, these experimental groups regained their normal weight. The dose of CEE (800 mg/kg) was not genotoxic nor cytotoxic. On the contrary, the B[a]P increases the frequency of micronucleated normochromatic erythrocytes (MNNE) and reduces the rate of polychromatic erythrocytes (PE) at the end of the treatment period. With respect to the combined lots, a significant decrease in the MN rate was observed from the sixth to the eighth day of treatment with the two high doses applied; the highest protection (60%) was obtained with 800 mg/kg of CEE. The same dose showed an anticytotoxic effect which corresponded to an improvement of 62.5% in relation to the animals administered with the B[a]P. In the second period, all groups reached values that have been seen in the control group animals. Our results suggest that the inhibition of clastogenicity of the cranberry ethanolic extract against B[a]P is related to the antioxidant capacity of the combination of phytochemicals present in its chemical composition. Full article
Open AccessArticle Assessment of Worldwide Genetic Diversity of Siberian Wild Rye (Elymus sibiricus L.) Germplasm Based on Gliadin Analysis
Molecules 2012, 17(4), 4424-4434; https://doi.org/10.3390/molecules17044424
Received: 6 February 2012 / Revised: 9 March 2012 / Accepted: 26 March 2012 / Published: 12 April 2012
Cited by 9 | PDF Full-text (531 KB) | HTML Full-text | XML Full-text
Abstract
E. sibiricus L., the type species of the genus Elymus, is a perennial, self-pollinating and allotetraploid grass indigenous to Northern Asia, which in some countries can be cultivated as an important forage grass. In the present study, eighty-six Elymus sibiricus accessions, mostly
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E. sibiricus L., the type species of the genus Elymus, is a perennial, self-pollinating and allotetraploid grass indigenous to Northern Asia, which in some countries can be cultivated as an important forage grass. In the present study, eighty-six Elymus sibiricus accessions, mostly from different parts of Asia, were assayed by gliadin markers based on Acid Polyacrylamide Gel Electrophoresis to differentiate and explore their genetic relationships. The genetic similarity matrix was calculated by 47 polymorphic bands, which ranged from 0.108 to 0.952 with an average of 0.373. The total Shannon diversity index (Ho) and the Simpson index (He) was 0.460 and 0.302, respectively. Cluster analysis showed a clear demarcation between accessions from Qinghai-Tibetan Plateau, China and the others as separate groups. The clustering pattern was probably dependent on geographic origin and ecological adaptability of the accessions. The population structure analysis based on Shannon indices showed that the proportion of variance within and among the five geographic regions of the Northern Hemisphere was 55.9 and 44.1%, respectively, or 63.4 and 36.6% within and among six Chinese provinces. This distinct geographical divergence was perhaps depended on ecogeographical conditions such as climate difference and mountain distribution. The results of gladin analysis in this study are useful for the collection and preservation of E. sibiricus germplasm resources. Full article
(This article belongs to the Section Molecular Diversity)
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Open AccessReview Honey: A Novel Antioxidant
Molecules 2012, 17(4), 4400-4423; https://doi.org/10.3390/molecules17044400
Received: 25 February 2012 / Revised: 30 March 2012 / Accepted: 1 April 2012 / Published: 12 April 2012
Cited by 100 | PDF Full-text (257 KB) | HTML Full-text | XML Full-text
Abstract
The global prevalence of chronic diseases such as diabetes mellitus, hypertension, atherosclerosis, cancer and Alzheimer's disease is on the rise. These diseases, which constitute the major causes of death globally, are associated with oxidative stress. Oxidative stress is defined as an “imbalance between
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The global prevalence of chronic diseases such as diabetes mellitus, hypertension, atherosclerosis, cancer and Alzheimer's disease is on the rise. These diseases, which constitute the major causes of death globally, are associated with oxidative stress. Oxidative stress is defined as an “imbalance between oxidants and antioxidants in favor of the oxidants, potentially leading to damage”. Individuals with chronic diseases are more susceptible to oxidative stress and damage because they have elevated levels of oxidants and/or reduced antioxidants. This, therefore, necessitates supplementation with antioxidants so as to delay, prevent or remove oxidative damage. Honey is a natural substance with many medicinal effects such as antibacterial, hepatoprotective, hypoglycemic, reproductive, antihypertensive and antioxidant effects. This review presents findings that indicate honey may ameliorate oxidative stress in the gastrointestinal tract (GIT), liver, pancreas, kidney, reproductive organs and plasma/serum. Besides, the review highlights data that demonstrate the synergistic antioxidant effect of honey and antidiabetic drugs in the pancreas, kidney and serum of diabetic rats. These data suggest that honey, administered alone or in combination with conventional therapy, might be a novel antioxidant in the management of chronic diseases commonly associated with oxidative stress. In view of the fact that the majority of these data emanate from animal studies, there is an urgent need to investigate this antioxidant effect of honey in human subjects with chronic or degenerative diseases. Full article
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Open AccessArticle Adsorption Behavior of Fe(II) and Fe(III) Ions on Thiourea Cross-Linked Chitosan with Fe(III) as Template
Molecules 2012, 17(4), 4388-4399; https://doi.org/10.3390/molecules17044388
Received: 27 February 2012 / Revised: 6 April 2012 / Accepted: 6 April 2012 / Published: 11 April 2012
Cited by 19 | PDF Full-text (486 KB) | HTML Full-text | XML Full-text
Abstract
A new type of thiourea cross-linked chitosan with Fe(III) as template (TCCTS template) was synthesized. The adsorption of Fe(II) and Fe(III) on this TCCTS template was studied. The factors affecting adsorption such as pH and contact time were considered. The results showed that
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A new type of thiourea cross-linked chitosan with Fe(III) as template (TCCTS template) was synthesized. The adsorption of Fe(II) and Fe(III) on this TCCTS template was studied. The factors affecting adsorption such as pH and contact time were considered. The results showed that the optimum pH value for adsorption was pH = 5.0 and the adsorption equilibrium time was about 60 min. The adsorption isotherms and kinetics were investigated, and the equilibrium data agreed very well with the Langmuir model and the pseudo second-order model could describe adsorption process better than the pseudo first-order model. Results also showed that TCCTS template was a favourable adsorbent for Fe(II) and Fe(III) in aqueous solution. Full article
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Open AccessArticle Chemical Characteristics and Antioxidant Properties of Crude Water Soluble Polysaccharides from Four Common Edible Mushrooms
Molecules 2012, 17(4), 4373-4387; https://doi.org/10.3390/molecules17044373
Received: 14 February 2012 / Revised: 6 April 2012 / Accepted: 6 April 2012 / Published: 11 April 2012
Cited by 35 | PDF Full-text (276 KB) | HTML Full-text | XML Full-text
Abstract
Four crude water soluble polysaccharides, CABP, CAAP, CFVP and CLDP, were isolated from common edible mushrooms, including Agaricus bisporus, Auricularia auricula, Flammulina velutipes and Lentinus edodes, and their chemical characteristics and antioxidant properties were determined. Fourier Transform-infrared analysis showed that
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Four crude water soluble polysaccharides, CABP, CAAP, CFVP and CLDP, were isolated from common edible mushrooms, including Agaricus bisporus, Auricularia auricula, Flammulina velutipes and Lentinus edodes, and their chemical characteristics and antioxidant properties were determined. Fourier Transform-infrared analysis showed that the four crude polysaccharides were all composed of β-glycoside linkages. The major monosaccharide compositions were D-galactose, D-glucose and D-mannose for CABP, CAAP and CLDP, while CFVP was found to consist of L-arabinose, D-galactose, D-glucose and D-mannose. The main molecular weight distributions of CABP and the other three polysaccharides were 66.0 × 104 Da, respectively. Antioxidant properties of the four polysaccharides were evaluated in in vitro systems and CABP showed the best antioxidant properties. The studied mushroom species could potentially be used in part of well-balanced diets and as a source of antioxidant compounds. Full article
(This article belongs to the Special Issue Natural Polysaccharides: Chemistry, Bioactivity and Analysis)
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Open AccessArticle Bio-Functional Constituents from the Stems of Liriodendron tulipifera
Molecules 2012, 17(4), 4357-4372; https://doi.org/10.3390/molecules17044357
Received: 7 March 2012 / Revised: 29 March 2012 / Accepted: 31 March 2012 / Published: 10 April 2012
Cited by 19 | PDF Full-text (532 KB) | HTML Full-text | XML Full-text
Abstract
Four known compounds have been isolated from the stems of Liriodendron tulipifera, and the structures of these pure constituents were determined using spectroscopic analysis. Isolated compounds were screened for free radical scavenging ability, metal chelating power assay and ferric reducing antioxidant power
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Four known compounds have been isolated from the stems of Liriodendron tulipifera, and the structures of these pure constituents were determined using spectroscopic analysis. Isolated compounds were screened for free radical scavenging ability, metal chelating power assay and ferric reducing antioxidant power assay (FRAP). The anti-tyrosinase effects of L. tulipifera compounds were calculated the inhibition of hydroxylation of L-tyrosine to L-dopa according to an in vitro mushroom tyrosinase assay. The study also examined the bio-effects of the four compounds on the human melanoma A375.S2, and showed that liriodenine (1) and (-)-norglaucine (4) significantly inhibited the proliferation of melanoma cells in the cell viability assay. Wound healing results indicated that liriodenine (1), (-)-glaucine (3) and (-)-norglaucine (4) exerted anti-migration potential. Interestingly, (-)-glaucine (3), neither liriodenine (1) nor (-)-norglaucine (4) showed promising anti-migration potential without inducing significant cytotoxicity. Furthermore, a dramatically increased level of intracellular reactive oxygen species (ROS) was detected from (-)-glaucine (3). The cell cycle assessment demonstrated a moderate G2/M accumulation by (-)-glaucine (3). The above results revealed the anti-cancer effects of L. tulipifera compounds, especially on the anti-migration ability indicating the promising chemopreventive agents to human skin melanoma cells. Full article
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