Next Issue
Previous Issue

E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Table of Contents

Molecules, Volume 19, Issue 7 (July 2014), Pages 8707-10669

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
View options order results:
result details:
Displaying articles 1-121
Export citation of selected articles as:

Research

Jump to: Review, Other

Open AccessArticle Determination of Volatile Organic Compounds (VOCs) from Wrapping Films and Wrapped PDO Italian Cheeses by Using HS-SPME and GC/MS
Molecules 2014, 19(7), 8707-8724; https://doi.org/10.3390/molecules19078707
Received: 30 April 2014 / Revised: 18 June 2014 / Accepted: 19 June 2014 / Published: 25 June 2014
Cited by 7 | PDF Full-text (709 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Nowadays food wrapping assures attractive presentation and simplifies self-service shopping. Polyvinylchloride (PVC)- and polyethylene (PE)-based cling-films are widely used worldwide for wrapping cheeses. For this purpose, films used in retail possess suitable technical properties such as clinginess and unrolling capacity, that are achieved
[...] Read more.
Nowadays food wrapping assures attractive presentation and simplifies self-service shopping. Polyvinylchloride (PVC)- and polyethylene (PE)-based cling-films are widely used worldwide for wrapping cheeses. For this purpose, films used in retail possess suitable technical properties such as clinginess and unrolling capacity, that are achieved by using specific plasticizers during their manufacturing process. In the present study, the main VOCs of three cling-films (either PVC-based or PE-based) for retail use were characterized by means of Solid-Phase Micro-Extraction and GC/MS. In addition, the effects of cling film type and contact time on the migration of VOCs from the films to four different PDO Italian cheeses during cold storage under light or dark were also investigated. Among the VOCs isolated from cling-films, PVC released 2-ethylhexanol and triacetin. These compounds can likely be considered as a “non-intentionally added substance”. These same compounds were also detected in cheeses wrapped in PVC films with the highest concentration found after 20 days storage. The PE cling-film was shown to possess a simpler VOC profile, lacking some molecules peculiar to PVC films. The same conclusions can be drawn for cheeses wrapped in the PE cling-film. Other VOCs found in wrapped cheeses were likely to have been released either by direct transfer from the materials used for the manufacture of cling-films or from contamination of the films. Overall, HS-SPME is shown to be a rapid and solvent free technique to screen the VOCs profile of cling-films, and to detect VOCs migration from cling-films to cheese under real retail storage conditions. Full article
(This article belongs to the Special Issue Microextraction)
Figures

Figure 1

Open AccessArticle Synthesis, Anti-microbial and Molecular Docking Studies of Quinazolin-4(3H)-one Derivatives
Molecules 2014, 19(7), 8725-8739; https://doi.org/10.3390/molecules19078725
Received: 15 April 2014 / Revised: 6 June 2014 / Accepted: 9 June 2014 / Published: 25 June 2014
Cited by 11 | PDF Full-text (1029 KB) | HTML Full-text | XML Full-text
Abstract
In this work, synthesis, antimicrobial activities and molecular docking studies of some new series of substituted quinazolinone 2ah and 3ad were described. Starting form 2-aminobenzamide derivatives 1, a new series of quinazolinone derivatives has been synthesized, in high
[...] Read more.
In this work, synthesis, antimicrobial activities and molecular docking studies of some new series of substituted quinazolinone 2ah and 3ad were described. Starting form 2-aminobenzamide derivatives 1, a new series of quinazolinone derivatives has been synthesized, in high yields, assisted by microwave and classical methods. Some of these substituted quinazolinones were tested for their antimicrobial activity against Gram-negative bacteria (Pseudomonas aeruginosa and Esherichia coli) and Gram-positive bacteria (Staphylococcus aureus, and Bacillus subtilis), and anti-fungal activity against (Aspergillus fumigatus, Saccharomyces cervevisiae, and Candida albicans) using agar well diffusion method. Among the prepared products, 3-benzyl-2-(4-chlorophenyl)quinazolin-4(3H)-one (3a) was found to exhibits the most potent in vitro anti-microbial activity with MICs of 25.6 ± 0.5, 24.3 ± 0.4, 30.1 ± 0.6, and 25.1 ± 0.5 µg/mL against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Esherichia coli, respectively. Compound 3a was found to exhibits the most potent in vitro anti-fungal activity with MICs of 18.3 ± 0.6, 23.1 ± 0.4, and 26.1 ± 0. 5 µg/mL against Aspergillus fumigatus, Saccharomyces cervevisiae, and Candidaal bicans, respectively. Full article
(This article belongs to the Section Organic Chemistry)
Figures

Graphical abstract

Open AccessArticle In Vitro and in Vivo Antitumor Activity of Scutebarbatine A on Human Lung Carcinoma A549 Cell Lines
Molecules 2014, 19(7), 8740-8751; https://doi.org/10.3390/molecules19078740
Received: 10 May 2014 / Revised: 30 May 2014 / Accepted: 16 June 2014 / Published: 25 June 2014
Cited by 16 | PDF Full-text (366 KB) | HTML Full-text | XML Full-text
Abstract
During our systematic study on the anticancer activities of Scutellaria barbata, scutebarbatine A (SBT-A), one of the major alkaloids in S. barbata, was found to have antitumor effects on A549 cells. Thus, we designed the present study to investigate in detail
[...] Read more.
During our systematic study on the anticancer activities of Scutellaria barbata, scutebarbatine A (SBT-A), one of the major alkaloids in S. barbata, was found to have antitumor effects on A549 cells. Thus, we designed the present study to investigate in detail the antitumor effects of SBT-A. The cytotoxic effect of SBT-A on A549 in vitro were determined by an MTT assay and evaluated by IC50 values. Furthermore, results of Hoechst 33258 and Annexin V/PI staining assays demonstrated that SBT-A had significant antitumor effects on A549 cells via apoptosis, in a concentration-dependent manner. What’s more, the mechanism was explored by western blotting, and our study revealed that SBT-A can up-regulate the expressions of cytochrome c, caspase-3 and 9, and down-regulate the levels of Bcl-2 in A549 cells. Finally, the antitumor effects of SBT-A were evaluated in vivo by using transplanted tumor nude mice, and the results confirmed that SBT-A has a notable antitumor effect on A549 cancer via mitochondria-mediated apoptosis. Collectively, our results demonstrated that SBT-A showed significant antitumor effects on A549 cells in vivo and in vitro via mitochondria-mediated apoptosis by up-regulating expressions of caspase-3 and 9, and down-regulating Bcl-2. Full article
Figures

Figure 1

Open AccessArticle Preparative Separation of Alkaloids from Picrasma quassioides (D. Don) Benn. by Conventional and pH-Zone-Refining Countercurrent Chromatography
Molecules 2014, 19(7), 8752-8761; https://doi.org/10.3390/molecules19078752
Received: 22 May 2014 / Revised: 12 June 2014 / Accepted: 18 June 2014 / Published: 25 June 2014
Cited by 8 | PDF Full-text (425 KB) | HTML Full-text | XML Full-text
Abstract
Two high-speed countercurrent chromatography (HSCCC) modes were compared by separation of major alkaloids from crude extract of Picrasma quassioides. The conventional HSCCC separation was performed with a two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:4.5:5.5, v/v/v/v) with 200 mg loading. pH-Zone-refining
[...] Read more.
Two high-speed countercurrent chromatography (HSCCC) modes were compared by separation of major alkaloids from crude extract of Picrasma quassioides. The conventional HSCCC separation was performed with a two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:4.5:5.5, v/v/v/v) with 200 mg loading. pH-Zone-refining CCC was performed with two-phase solvent system composed of petroleum ether–ethyl acetate–n-butanol–water (3:2:7:9, v/v/v/v) where triethylamine (10 mM) was added to the upper organic stationary phase and hydrochloric acid (5 mM) was added to the lower aqueous phase with 2 g loading. From 2 g of crude extract, 87 mg of 5-methoxycanthin-6-one (a), 38 mg of 1-methoxy-β-carboline (b), 134 mg of 1-ethyl-4,8-dimethoxy-β-carboline (c), 74 mg of 1-ethoxycarbonyl-β-carboline (d), 56 mg of 1-vinyl-4,8-dimethoxy-β-carboline (e) and 26 mg of 1-vinyl-4-dimethoxy-β-carboline (f) were obtained with purities of over 97.0%. The results indicated that pH-zone-refining CCC is an excellent separations tool at the multigram level. Full article
Figures

Figure 1

Open AccessArticle Cytotoxic Aporphine Alkaloids from Leaves and Twigs of Pseuduvaria trimera (Craib)
Molecules 2014, 19(7), 8762-8772; https://doi.org/10.3390/molecules19078762
Received: 21 May 2014 / Revised: 17 June 2014 / Accepted: 19 June 2014 / Published: 25 June 2014
Cited by 3 | PDF Full-text (334 KB) | HTML Full-text | XML Full-text
Abstract
From ethyl acetate-methanol extracts of leaves and twigs of Pseuduvaria trimera a new aporphine alkaloid; 8-hydroxy-1,4,5-trimethoxy-7-oxoaporphine or 8-hydroxyartabonatine C (1) was isolated, together with the known 1,2,3-trimethoxy-4,5-dioxo-6a,7-dehydroaporphine (ouregidione, 2). Their structures were elucidated by a combination of spectral methods; mainly
[...] Read more.
From ethyl acetate-methanol extracts of leaves and twigs of Pseuduvaria trimera a new aporphine alkaloid; 8-hydroxy-1,4,5-trimethoxy-7-oxoaporphine or 8-hydroxyartabonatine C (1) was isolated, together with the known 1,2,3-trimethoxy-4,5-dioxo-6a,7-dehydroaporphine (ouregidione, 2). Their structures were elucidated by a combination of spectral methods; mainly 2D NMR; IR and MS. Compounds 1 and 2 exhibited cytotoxic activity with IC50 values of 26.36 ± 5.18 μM and 12.88 ± 2.49 μM, respectively, for human hepatocellular carcinoma HepG2 cells, and 64.75 ± 4.45 and 67.06 ± 3.5 μM, respectively, for human breast cancer MDA-MB231 cells. Both compounds displayed anti-cancer activity but less than that of doxorubicin; a conventional chemotherapeutic drug, the IC50 levels of which were 2.21 ± 1.72 and 1.83 ± 0.09 μM for HepG2 and MDA-MB231 cells, respectively. Full article
(This article belongs to the Special Issue Alkaloids: Novel Therapeutic Perspectives)
Figures

Figure 1

Open AccessArticle Two-Step Separation of Nostotrebin 6 from Cultivated Soil Cyanobacterium (Nostoc sp.) by High Performance Countercurrent Chromatography
Molecules 2014, 19(7), 8773-8787; https://doi.org/10.3390/molecules19078773
Received: 7 May 2014 / Revised: 17 June 2014 / Accepted: 18 June 2014 / Published: 25 June 2014
Cited by 4 | PDF Full-text (676 KB) | HTML Full-text | XML Full-text
Abstract
High performance countercurrent chromatography (HPCCC) was successfully applied for the separation of nostotrebin 6 from cultivated soil cyanobacteria in a two-step operation. A two-phase solvent system composed of n-hexane–ethyl acetate–methanol–water (4:5:4:5, v/v/v/v) was employed for the HPCCC separation. In the first-step operation,
[...] Read more.
High performance countercurrent chromatography (HPCCC) was successfully applied for the separation of nostotrebin 6 from cultivated soil cyanobacteria in a two-step operation. A two-phase solvent system composed of n-hexane–ethyl acetate–methanol–water (4:5:4:5, v/v/v/v) was employed for the HPCCC separation. In the first-step operation, its neutral upper phase was used as stationary phase and its basic lower phase (1% NH3 in lower phase) was employed as mobile phase at a flow rate of 1 mL/min. In the second operation step, its neutral upper phase was used as stationary phase, whereas both its neutral lower phase and basic lower phase were employed as mobile phase with a linear gradient elution at a flow rate of 0.8 mL/min. The revolution speed and temperature of the separation column were 1,000 rpm and 30 °C, respectively. Using HPCCC followed by clean-up on Sephadex LH-20 gel, 4 mg of nostotrebin 6 with a purity of 99% as determined by HPLC/DAD-ESI-HRMS was obtained from 100 mg of crude extract. The chemical identity of the isolated compound was confirmed by comparing its spectroscopic data (UV, ESI-HRMS, ESI-HRMS2) with those of an authentic standard and data available in the literature. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Graphical abstract

Open AccessArticle Phenoxyacetohydrazide Schiff Bases: β-Glucuronidase Inhibitors
Molecules 2014, 19(7), 8788-8802; https://doi.org/10.3390/molecules19078788
Received: 7 May 2014 / Revised: 6 June 2014 / Accepted: 11 June 2014 / Published: 25 June 2014
Cited by 22 | PDF Full-text (332 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Phenoxyacetohydrazide Schiff base analogs 128 have been synthesized and their in vitro β-glucouoronidase inhibition potential studied. Compounds 1 (IC50 = 9.20 ± 0.32 µM), 5 (IC50 = 9.47 ± 0.16 µM), 7 (IC50 = 14.7 ± 0.19
[...] Read more.
Phenoxyacetohydrazide Schiff base analogs 128 have been synthesized and their in vitro β-glucouoronidase inhibition potential studied. Compounds 1 (IC50 = 9.20 ± 0.32 µM), 5 (IC50 = 9.47 ± 0.16 µM), 7 (IC50 = 14.7 ± 0.19 µM), 8 (IC50 = 15.4 ± 1.56 µM), 11 (IC50 = 19.6 ± 0.62 µM), 12 (IC50 = 30.7 ± 1.49 µM), 15 (IC50 = 12.0 ± 0.16 µM), 21 (IC50 = 13.7 ± 0.40 µM) and 22 (IC50 = 22.0 ± 0.14 µM) showed promising β-glucuronidase inhibition activity, better than the standard (D-saccharic acid-1,4-lactone, IC50 = 48.4 ± 1.25 µM). Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Synthesis and Cytotoxicity Evaluation of Naphthalimide Derived N-Mustards
Molecules 2014, 19(7), 8803-8819; https://doi.org/10.3390/molecules19078803
Received: 21 May 2014 / Revised: 10 June 2014 / Accepted: 17 June 2014 / Published: 25 June 2014
Cited by 2 | PDF Full-text (1097 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A series of N-mustards, which was conjugated to mono- or bis-naphthalimides with a flexible amine link, were synthesized and evaluated for cytotoxicity against five cancer cell lines (HCT-116, PC-3, U87 MG, Hep G2 and SK-OV-3). Several compounds displayed better activities than the
[...] Read more.
A series of N-mustards, which was conjugated to mono- or bis-naphthalimides with a flexible amine link, were synthesized and evaluated for cytotoxicity against five cancer cell lines (HCT-116, PC-3, U87 MG, Hep G2 and SK-OV-3). Several compounds displayed better activities than the control compound amonafide. Further evaluations by fluorescence spectroscopy studies and DNA-interstrand cross-linking assays revealed that the derivatives showed both alkylating and intercalating properties. Among the derivatives, the bis-naphthalimide N-mustard derivative 11b was found to exhibit the highest cytotoxic activity and DNA cross-linking ability. Both 11b and 7b induce HCT-116 cell apoptosis by S phase arrest. Full article
Figures

Figure 1

Open AccessArticle Regulatory Effects of Fisetin on Microglial Activation
Molecules 2014, 19(7), 8820-8839; https://doi.org/10.3390/molecules19078820
Received: 30 April 2014 / Revised: 13 June 2014 / Accepted: 18 June 2014 / Published: 26 June 2014
Cited by 15 | PDF Full-text (2770 KB) | HTML Full-text | XML Full-text
Abstract
Increasing evidence suggests that inflammatory processes in the central nervous system that are mediated by microglial activation play a key role in neurodegeneration. Fisetin, a plant flavonol commonly found in fruits and vegetables, is frequently added to nutritional supplements due to its antioxidant
[...] Read more.
Increasing evidence suggests that inflammatory processes in the central nervous system that are mediated by microglial activation play a key role in neurodegeneration. Fisetin, a plant flavonol commonly found in fruits and vegetables, is frequently added to nutritional supplements due to its antioxidant properties. In the present study, treatment with fisetin inhibited microglial cell migration and ROS (reactive oxygen species) production. Treatment with fisetin also effectively inhibited LPS plus IFN-γ-induced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) expression in microglial cells. Furthermore, fisetin also reduced expressions of iNOS and NO by stimulation of peptidoglycan, the major component of the Gram-positive bacterium cell wall. Fisetin also inhibited the enhancement of LPS/IFN-γ- or peptidoglycan-induced inflammatory mediator IL (interlukin)-1 β expression. Besides the antioxidative and anti-inflammatory effects of fisetin, our study also elucidates the manner in fisetin-induced an endogenous anti-oxidative enzyme HO (heme oxygenase)-1 expression. Moreover, the regulatory molecular mechanism of fisetin-induced HO-1 expression operates through the PI-3 kinase/AKT and p38 signaling pathways in microglia. Notably, fisetin also significantly attenuated inflammation-related microglial activation and coordination deficit in mice in vivo. These findings suggest that fisetin may be a candidate agent for the development of therapies for inflammation-related neurodegenerative diseases. Full article
(This article belongs to the Special Issue Natural Antioxidants and Ageing)
Figures

Figure 1

Open AccessCommunication A New Xanthone from Moutabea guianensis Aubl
Molecules 2014, 19(7), 8885-8889; https://doi.org/10.3390/molecules19078885
Received: 22 May 2014 / Revised: 18 June 2014 / Accepted: 19 June 2014 / Published: 26 June 2014
Cited by 2 | PDF Full-text (192 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The ethyl acetate extract of the roots of Moutabea guianensis gave 1,6-dihydroxy-4,7,8-trimethoxy-9H-xanthen-9-one (1), a new xanthone. The isolation was accomplished by column chromatography on silica gel and the structural elucidation of this compound was established by spectroscopic analyses including
[...] Read more.
The ethyl acetate extract of the roots of Moutabea guianensis gave 1,6-dihydroxy-4,7,8-trimethoxy-9H-xanthen-9-one (1), a new xanthone. The isolation was accomplished by column chromatography on silica gel and the structural elucidation of this compound was established by spectroscopic analyses including 1D and 2D NMR and HRESIMS. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessCommunication Using MUSIC and CC(CO)NH for Backbone Assignment of Two Medium-Sized Proteins Not Fully Accessible to Standard 3D NMR
Molecules 2014, 19(7), 8890-8903; https://doi.org/10.3390/molecules19078890
Received: 5 May 2014 / Revised: 5 June 2014 / Accepted: 12 June 2014 / Published: 26 June 2014
Cited by 1 | PDF Full-text (306 KB) | HTML Full-text | XML Full-text
Abstract
The backbone assignment of medium-sized proteins is rarely as straightforward as that of small proteins, and thus often requires creative solutions. Here, we describe the application of a combination of standard 3D heteronuclear methods with CC(CO)NH and a variety of MUltiplicity Selective In-phase
[...] Read more.
The backbone assignment of medium-sized proteins is rarely as straightforward as that of small proteins, and thus often requires creative solutions. Here, we describe the application of a combination of standard 3D heteronuclear methods with CC(CO)NH and a variety of MUltiplicity Selective In-phase Coherence transfer (MUSIC) experiments. Both CC(CO)NH and MUSIC are, in theory, very powerful methods for the backbone assignment of proteins. Due to low sensitivity, their use has usually been linked to small proteins only. However, we found that combining CC(CO)NH and MUSIC experiments simplified the assignment of two challenging medium-sized proteins of 13 and 19.5 kDa, respectively. These methods are to some extent complementary to each other: CC(CO)NH acquired with a long isotropic mixing time can identify amino acids with large aliphatic side chains. Whereas the most sensitive MUSIC experiments identify amino acid types that cannot be detected by CC(CO)NH, comprising the residues with acid and amide groups, and aromatic rings in their side chains. Together these methods provide a means of identifying the majority of peaks in the 2D 15N HSQC spectrum which simplifies the backbone assignment work even for proteins, e.g., small kinases, whose standard spectra resulted in little spectral resolution and low signal intensities. Full article
(This article belongs to the Special Issue Design and Study of Kinase Inhibitors)
Figures

Figure 1

Open AccessArticle Mulberry Fruit Extract Protects Pancreatic β-Cells against Hydrogen Peroxide-Induced Apoptosis via Antioxidative Activity
Molecules 2014, 19(7), 8904-8915; https://doi.org/10.3390/molecules19078904
Received: 20 May 2014 / Revised: 7 June 2014 / Accepted: 18 June 2014 / Published: 26 June 2014
Cited by 9 | PDF Full-text (1193 KB) | HTML Full-text | XML Full-text
Abstract
Among the many environmental stresses, excessive production of reactive oxygen species (ROS) and the ensuring oxidative stress are known to cause significant cellular damage. This has clinical implications in the onset of type 1 diabetes, which is triggered by the destruction of pancreatic
[...] Read more.
Among the many environmental stresses, excessive production of reactive oxygen species (ROS) and the ensuring oxidative stress are known to cause significant cellular damage. This has clinical implications in the onset of type 1 diabetes, which is triggered by the destruction of pancreatic β-cells and is associated with oxidative stress. In this study, we investigated the protective and antioxidative effects of mulberry extract (ME) in insulin-producing pancreatic β-cells. We found that ME protects pancreatic β-cells against hydrogen peroxide (H2O2)-induced oxidative stress and the associated apoptotic cell death. ME treatment significantly reduced the levels of H2O2-induced 2-diphenyl-1-picrylhydrazyl (DPPH) radicals, and lipid peroxidation and intracellular ROS accumulation. In addition, ME inhibited DNA condensation and/or fragmentation induced by H2O2. These results suggest that ME protects pancreatic β-cells against hydrogen peroxide-induced oxidative stress. Full article
Figures

Figure 1

Open AccessArticle Synthesis and Evaluation of 2,4-Disubstituted Quinazoline Derivatives with Potent Anti-Angiogenesis Activities
Molecules 2014, 19(7), 8916-8932; https://doi.org/10.3390/molecules19078916
Received: 23 April 2014 / Revised: 15 June 2014 / Accepted: 18 June 2014 / Published: 26 June 2014
Cited by 6 | PDF Full-text (947 KB) | HTML Full-text | XML Full-text
Abstract
A series of 2,4-disubstituted quinazoline derivatives were designed and synthesized. The biological results showed that most of quinazoline derivatives exhibited potent antiproliferative activities against a panel of three tumor cell lines and a good inhibitory effect against the adhesion and migration of human
[...] Read more.
A series of 2,4-disubstituted quinazoline derivatives were designed and synthesized. The biological results showed that most of quinazoline derivatives exhibited potent antiproliferative activities against a panel of three tumor cell lines and a good inhibitory effect against the adhesion and migration of human umbilical vein endothelial cells (HUVECs). Among these compounds, 11d was the most potent agent, that also exhibited the highest anti-angiogenesis activities in the chick embryo chorioallantoic membrane (CAM) assay. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Flavonoids with M1 Muscarinic Acetylcholine Receptor Binding Activity
Molecules 2014, 19(7), 8933-8948; https://doi.org/10.3390/molecules19078933
Received: 27 February 2014 / Revised: 20 June 2014 / Accepted: 23 June 2014 / Published: 27 June 2014
Cited by 4 | PDF Full-text (4490 KB) | HTML Full-text | XML Full-text
Abstract
Muscarinic acetylcholine receptor-active compounds have potential for the treatment of Alzheimer’s disease. In this study, a series of natural and synthetic flavones and flavonols was assayed in vitro for their ability to inhibit radioligand binding at human cloned M1 muscarinic receptors. Several
[...] Read more.
Muscarinic acetylcholine receptor-active compounds have potential for the treatment of Alzheimer’s disease. In this study, a series of natural and synthetic flavones and flavonols was assayed in vitro for their ability to inhibit radioligand binding at human cloned M1 muscarinic receptors. Several compounds were found to possess competitive binding affinity (Ki = 40–110 µM), comparable to that of acetylcholine (Ki = 59 µM). Despite the fact that these compounds lack a positively-charged ammonium group under physiological conditions, molecular modelling studies suggested that they bind to the orthosteric site of the receptor, mainly through non-polar interactions. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Graphical abstract

Open AccessArticle Discovery of Gramine Derivatives That Inhibit the Early Stage of EV71 Replication in Vitro
Molecules 2014, 19(7), 8949-8964; https://doi.org/10.3390/molecules19078949
Received: 14 April 2014 / Revised: 19 June 2014 / Accepted: 20 June 2014 / Published: 27 June 2014
Cited by 8 | PDF Full-text (658 KB) | HTML Full-text | XML Full-text
Abstract
Enterovirus 71 (EV71) is a notable causative agent of hand, foot, and mouth disease in children, which is associated with an increased incidence of severe neurological disease and death, yet there is no specific treatment or vaccine for EV71 infections. In this study,
[...] Read more.
Enterovirus 71 (EV71) is a notable causative agent of hand, foot, and mouth disease in children, which is associated with an increased incidence of severe neurological disease and death, yet there is no specific treatment or vaccine for EV71 infections. In this study, the antiviral activity of gramine and 21 gramine derivatives against EV71 was investigated in cell-based assays. Eighteen derivatives displayed some degree of inhibitory effects against EV71, in that they could effectively inhibit virus-induced cytopathic effects (CPEs), but the anti-EV71 activity of the lead compound gramine was not observed. Studies on the preliminary modes of action showed that these compounds functioned by targeting the early stage of the EV71 lifecycle after viral entry, rather than inactivating the virus directly, inhibiting virus adsorption or affecting viral release from the cells. Among these derivatives, one (compound 4s) containing pyridine and benzothiazole units showed the most potency against EV71. Further studies demonstrated that derivative 4s could profoundly inhibit viral RNA replication, protein synthesis, and virus-induced apoptosis in RD cells. These results indicate that derivative 4s might be a feasible therapeutic agent against EV71 infection and that these gramine derivatives may provide promising lead scaffolds for the further design and synthesis of potential antiviral agents. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Volatile Organic Compound Emissions from Different Stages of Cananga odorata Flower Development
Molecules 2014, 19(7), 8965-8980; https://doi.org/10.3390/molecules19078965
Received: 14 April 2014 / Revised: 15 June 2014 / Accepted: 17 June 2014 / Published: 27 June 2014
Cited by 4 | PDF Full-text (696 KB) | HTML Full-text | XML Full-text
Abstract
Headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to identify the volatile organic compounds (VOCs) of the different flower development stages of Cananga odorata for the evaluation of floral volatile polymorphism as a basis to determine the best time of harvest. Electronic nose
[...] Read more.
Headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to identify the volatile organic compounds (VOCs) of the different flower development stages of Cananga odorata for the evaluation of floral volatile polymorphism as a basis to determine the best time of harvest. Electronic nose results, coupled with discriminant factor analysis, suggested that emitted odors varied in different C. odorata flower development stages, including the bud, display-petal, initial-flowering, full-flowering, end-flowering, wilted-flower, and dried flower stages. The first two discriminant factors explained 97.52% of total system variance. Ninety-two compounds were detected over the flower life, and the mean Bray–Curtis similarity value was 52.45% among different flower development stages. A high level of volatile polymorphism was observed during flower development. The VOCs were largely grouped as hydrocarbons, esters, alcohols, aldehydes, phenols, acids, ketones, and ethers, and the main compound was β-caryophyllene (15.05%–33.30%). Other identified compounds were β-cubebene, D-germacrene, benzyl benzoate, and α-cubebene. Moreover, large numbers of VOCs were detected at intermediate times of flower development, and more hydrocarbons, esters, and alcohols were identified in the full-flowering stage. The full-flowering stage may be the most suitable period for C. odorata flower harvest. Full article
Figures

Figure 1

Open AccessArticle MAPLE Fabricated Fe3O4@Cinnamomum verum Antimicrobial Surfaces for Improved Gastrostomy Tubes
Molecules 2014, 19(7), 8981-8994; https://doi.org/10.3390/molecules19078981
Received: 20 May 2014 / Revised: 14 June 2014 / Accepted: 23 June 2014 / Published: 27 June 2014
Cited by 13 | PDF Full-text (1996 KB) | HTML Full-text | XML Full-text
Abstract
Cinnamomum verum-functionalized Fe3O4 nanoparticles of 9.4 nm in size were laser transferred by matrix assisted pulsed laser evaporation (MAPLE) technique onto gastrostomy tubes (G-tubes) for antibacterial activity evaluation toward Gram positive and Gram negative microbial colonization. X-ray diffraction analysis
[...] Read more.
Cinnamomum verum-functionalized Fe3O4 nanoparticles of 9.4 nm in size were laser transferred by matrix assisted pulsed laser evaporation (MAPLE) technique onto gastrostomy tubes (G-tubes) for antibacterial activity evaluation toward Gram positive and Gram negative microbial colonization. X-ray diffraction analysis of the nanoparticle powder showed a polycrystalline magnetite structure, whereas infrared mapping confirmed the integrity of C. verum (CV) functional groups after the laser transfer. The specific topography of the deposited films involved a uniform thin coating together with several aggregates of bio-functionalized magnetite particles covering the G-tubes. Cytotoxicity assays showed an increase of the G-tube surface biocompatibility after Fe3O4@CV treatment, allowing a normal development of endothelial cells up to five days of incubation. Microbiological assays on nanoparticle-modified G-tube surfaces have proved an improvement of anti-adherent properties, significantly reducing both Gram negative and Gram positive bacteria colonization. Full article
(This article belongs to the Special Issue Bio and Nanomaterials Based on Fe3O4)
Figures

Graphical abstract

Open AccessArticle Ultrasonic Extraction of Antioxidants from Chinese Sumac (Rhus typhina L.) Fruit Using Response Surface Methodology and Their Characterization
Molecules 2014, 19(7), 9019-9032; https://doi.org/10.3390/molecules19079019
Received: 23 April 2014 / Revised: 9 June 2014 / Accepted: 23 June 2014 / Published: 27 June 2014
Cited by 13 | PDF Full-text (383 KB) | HTML Full-text | XML Full-text
Abstract
For the first time, response surface methodology (RSM) using a Box-Behnken Design (BBD) was employed to optimize the conditions for ultrasonic assisted extraction (UAE) of antioxidants from Chinese sumac (Rhus typhina L.) fruits. Initially, influencing factors such as liquid-solid ratio, duration of
[...] Read more.
For the first time, response surface methodology (RSM) using a Box-Behnken Design (BBD) was employed to optimize the conditions for ultrasonic assisted extraction (UAE) of antioxidants from Chinese sumac (Rhus typhina L.) fruits. Initially, influencing factors such as liquid-solid ratio, duration of ultrasonic assisted extraction, pH range, extraction temperature and ethanol concentration were identified using single-factor experiments. Then, with respect to the three most significant influencing factors, the extraction process focusing on the DPPH· scavenging capacity of antioxidants was optimized using RSM. Results showed that the optimal conditions for antioxidant extraction were 13.03:1 (mL/g) liquid-solid ratio, 16.86 min extraction time and 40.51% (v/v) ethanol, and the desirability was 0.681. The UPLC-ESI-MS analysis results revealed eleven kinds of phenolic compounds, including four major rare anthocyanins, among the antioxidants. All these results suggest that UAE is efficient at extracting antioxidants and has the potential to be used in industry for this purpose. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessArticle Comparison of the Apoptotic Effects of Supercritical Fluid Extracts of Antrodia cinnamomea Mycelia on Hepatocellular Carcinoma Cells
Molecules 2014, 19(7), 9033-9050; https://doi.org/10.3390/molecules19079033
Received: 30 April 2014 / Revised: 19 June 2014 / Accepted: 19 June 2014 / Published: 27 June 2014
Cited by 7 | PDF Full-text (1519 KB) | HTML Full-text | XML Full-text
Abstract
Antrodia cinnamomea (AC) has been widely used as a folk medicine in the prevention and treatment of liver diseases, such as hepatitis, hepatic fibrosis, and hepatocellular carcinoma. Previous studies have indicated that triterpenoids and benzenoids show selective cytotoxicity against human hepatoma cell lines.
[...] Read more.
Antrodia cinnamomea (AC) has been widely used as a folk medicine in the prevention and treatment of liver diseases, such as hepatitis, hepatic fibrosis, and hepatocellular carcinoma. Previous studies have indicated that triterpenoids and benzenoids show selective cytotoxicity against human hepatoma cell lines. The aim of the study was to compare the triterpenoid content of extract and the extract-induced cytotoxicity in HepG2 cells from mycelia extracts of solid state cultured AC obtained by supercritical fluid extraction (SFE) and the conventional solvent extraction method. SFE with CO2 mixed with a constant amount of ethanol co-solvent (10% of CO2 volume) applied at different temperatures and pressures (40, 60 and 80 °C and, 20.7, 27.6 and 34.5 Mpa) was also compared in the study. Although the extraction yield of triterpenoids (59.7 mg/g) under the optimal extraction conditions of 34.5 MPa (5000 psi)/60 °C (designated as sample S-5000-60) was equivalent to the extraction yield using conventional liquid solvent extraction with ethanol (ETOH-E) at room temperature (60.33 mg/g), the cytotoxicity of the former against the proliferation of HepG2 cell line measured as the inhibition of 50% of cell growth activity (IC50) at dosages of 116.15, 57.82 and 43.96 µg/mL was superior to that of EtOH-E at 131.09, 80.04 and 48.30 µg/mL at 24, 48 and 72 h, respectively. Additionally, we further proved that the apoptotic effect of S-5000-60 presented a higher apoptosis ratio (21.5%) than ETOH-E (10.5%) according to annexin V-FITC and propidium iodide double staining assay results. The high affinity and selectivity of SFE on bioactive components resulted in a higher extraction efficiency than conventional solvent extraction. The chemical profile of the obtained extracts from solid state cultivated mycelium of AC was also determined by high-performance liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS), whereby three benzenoids and four triterpenoids were found for the first time in SFE extracts with 4,7-dimethoxy-5-methyl-l,3-benzodioxole (5.78 mg/g) being the most abundant component, followed by 2,4-dimethoxy-6-methylbenzene-1,3-diol (3.03 mg/g) and dehydroeburicoic acid (0.40 mg/g). Full article
Figures

Graphical abstract

Open AccessArticle Targeted Lipid Analysis of Haemolytic Mycelial Extracts of Aspergillus niger
Molecules 2014, 19(7), 9051-9069; https://doi.org/10.3390/molecules19079051
Received: 28 February 2014 / Revised: 19 June 2014 / Accepted: 23 June 2014 / Published: 30 June 2014
Cited by 1 | PDF Full-text (1144 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Ethanolic extracts of mycelia from Aspergillus niger (strain N402) grown in liquid media were observed to have haemolytic activity on bovine erythrocytes. This haemolytic activity decreased significantly during the time of growth (1–3 days). Moreover, when A. niger was grown on carbon-deprived medium,
[...] Read more.
Ethanolic extracts of mycelia from Aspergillus niger (strain N402) grown in liquid media were observed to have haemolytic activity on bovine erythrocytes. This haemolytic activity decreased significantly during the time of growth (1–3 days). Moreover, when A. niger was grown on carbon-deprived medium, the efficiency of this haemolytic activity in the ethanolic extracts was much lower than when grown in carbon-enriched medium, and became almost undetectable after 3 days of growth in carbon-deprived medium. The lipid composition of these ethanolic extracts was analysed by liquid chromatography–electrospray ionisation tandem mass spectrometry. This haemolytic activity can be mainly linked to the relative levels of the molar ratios of the unsaturated fatty acids and lysophosphatidylcholines. Full article
(This article belongs to the Special Issue Fatty Acids)
Figures

Graphical abstract

Open AccessArticle Characterization of Intact Neo-Glycoproteins by Hydrophilic Interaction Liquid Chromatography
Molecules 2014, 19(7), 9070-9088; https://doi.org/10.3390/molecules19079070
Received: 12 May 2014 / Revised: 18 June 2014 / Accepted: 19 June 2014 / Published: 30 June 2014
Cited by 13 | PDF Full-text (2269 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In this study, an HPLC HILIC-UV method was developed for the analysis of intact neo-glycoproteins. During method development the experimental conditions evaluated involved different HILIC columns (TSKgel Amide-80 and ZIC-pHILIC), and water-acetonitrile mixtures containing various types of acids and salts.
[...] Read more.
In this study, an HPLC HILIC-UV method was developed for the analysis of intact neo-glycoproteins. During method development the experimental conditions evaluated involved different HILIC columns (TSKgel Amide-80 and ZIC-pHILIC), and water-acetonitrile mixtures containing various types of acids and salts. The final selected method was based on a TSKgel Amide-80 column and a mobile phase composed of acetonitrile and water both containing 10 mM HClO4. The influence of temperature and sample preparation on the chromatographic performances of the HILIC method was also investigated. The method was applied to the separation of neo-glycoproteins prepared starting from the model protein RNase A by chemical conjugation of different glycans. Using the method here reported it was possible to monitor by UV detection the glycosylation reaction and assess the distribution of neo-glycoprotein isoforms without laborious sample workup prior to analysis. Full article
(This article belongs to the Special Issue Oligosaccharides and Glyco-Conjugates)
Figures

Figure 1

Open AccessArticle Cholesteryl-Modification of a Glucomannan from Bletilla striata and Its Hydrogel Properties
Molecules 2014, 19(7), 9089-9100; https://doi.org/10.3390/molecules19079089
Received: 25 May 2014 / Revised: 21 June 2014 / Accepted: 24 June 2014 / Published: 30 June 2014
Cited by 8 | PDF Full-text (671 KB) | HTML Full-text | XML Full-text
Abstract
A glucomannan-type polysaccharide, named BSP, was obtained from the tubers of Bletilla striata by ultrasonic-assisted extraction, ethanol precipitation, deproteination and gel-permeation chromatography. HPLC analysis revealed that BSP contained mannose and glucose in the molar ratio of 3.5:1. Its molecular weight (Mw) was estimated
[...] Read more.
A glucomannan-type polysaccharide, named BSP, was obtained from the tubers of Bletilla striata by ultrasonic-assisted extraction, ethanol precipitation, deproteination and gel-permeation chromatography. HPLC analysis revealed that BSP contained mannose and glucose in the molar ratio of 3.5:1. Its molecular weight (Mw) was estimated to be 20 kDa. Methylation analysis, FT-IR and NMR analyses indicated that BSP consisted of (1→4)-linked β-D-glucopyranosyl residues and (1→4)-linked β-D-mannopyranosyl residues. Cholesteryl succinate was linked to BSP to make it more amphiphilic and the degree of substitution of cholesteryl succinate-BSP was 3.2%. The critical micelle concentration of modified BSP was 0.001 mg/mL, suggesting it could self-assemble into nanoparticles in aqueous solution. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Graphical abstract

Open AccessArticle Bioactive Profiles, Antioxidant Activities, Nitrite Scavenging Capacities and Protective Effects on H2O2-Injured PC12 Cells of Glycyrrhiza Glabra L. Leaf and Root Extracts
Molecules 2014, 19(7), 9101-9113; https://doi.org/10.3390/molecules19079101
Received: 15 May 2014 / Revised: 24 June 2014 / Accepted: 25 June 2014 / Published: 30 June 2014
Cited by 16 | PDF Full-text (572 KB) | HTML Full-text | XML Full-text
Abstract
This study compared the total flavonoid content of Glycyrrhiza glabra L. leaf and root extracts. Results suggested that the total flavonoid content in the leaf extract was obviously higher than that in the root extract. Pinocembrin, the main compound in the leaf extract
[...] Read more.
This study compared the total flavonoid content of Glycyrrhiza glabra L. leaf and root extracts. Results suggested that the total flavonoid content in the leaf extract was obviously higher than that in the root extract. Pinocembrin, the main compound in the leaf extract after purification by column chromatography, showed good antioxidant activity and nitrite scavenging capacity, but moderate inhibitory effect on mushroom tyrosinase. Liquiritin was the main compound in root extract and possessed strong inhibitory effect on mushroom tyrosinase. Both compounds exhibited significant protection effect on H2O2-injured PC12 cells at a low concentration. These results indicate that Glycyrrhiza glabra L. leaf is potential as an important raw material for functional food. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessArticle Investigation of the Flexibility of Protein Kinases Implicated in the Pathology of Alzheimer’s Disease
Molecules 2014, 19(7), 9134-9159; https://doi.org/10.3390/molecules19079134
Received: 4 May 2014 / Revised: 16 June 2014 / Accepted: 19 June 2014 / Published: 30 June 2014
Cited by 7 | PDF Full-text (7383 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The pathological characteristics of Alzheimer’s Disease (AD) have been linked to the activity of three particular kinases—Glycogen Synthase Kinase 3β (GSK3β), Cyclin-Dependent Kinase 5 (CDK5) and Extracellular-signal Regulated Kinase 2 (ERK2). As a consequence, the design of selective, potent and drug-like inhibitors of
[...] Read more.
The pathological characteristics of Alzheimer’s Disease (AD) have been linked to the activity of three particular kinases—Glycogen Synthase Kinase 3β (GSK3β), Cyclin-Dependent Kinase 5 (CDK5) and Extracellular-signal Regulated Kinase 2 (ERK2). As a consequence, the design of selective, potent and drug-like inhibitors of these kinases is of particular interest. Structure-based design methods are well-established in the development of kinase inhibitors. However, progress in this field is limited by the difficulty in obtaining X-ray crystal structures suitable for drug design and by the inability of this method to resolve highly flexible regions of the protein that are crucial for ligand binding. To address this issue, we have undertaken a study of human protein kinases CDK5/p25, CDK5, ERK2 and GSK3β using both conventional molecular dynamics (MD) and the new Active Site Pressurisation (ASP) methodology, to look for kinase-specific patterns of flexibility that could be leveraged for the design of selective inhibitors. ASP was used to examine the intrinsic flexibility of the ATP-binding pocket for CDK5/p25, CDK5 and GSK3β where it is shown to be capable of inducing significant conformational changes when compared with X-ray crystal structures. The results from these experiments were used to quantify the dynamics of each protein, which supported the observations made from the conventional MD simulations. Additional information was also derived from the ASP simulations, including the shape of the ATP-binding site and the rigidity of the ATP-binding pocket. These observations may be exploited in the design of selective inhibitors of GSK3β, CDK5 and ERK2. Full article
(This article belongs to the Special Issue In-Silico Drug Design and In-Silico Screening)
Figures

Graphical abstract

Open AccessArticle Adsorption Characteristics of Sol Gel-Derived Zirconia for Cesium Ions from Aqueous Solutions
Molecules 2014, 19(7), 9160-9172; https://doi.org/10.3390/molecules19079160
Received: 19 April 2014 / Revised: 1 June 2014 / Accepted: 9 June 2014 / Published: 1 July 2014
Cited by 10 | PDF Full-text (372 KB) | HTML Full-text | XML Full-text
Abstract
Zirconia powder was synthesized via a sol gel method and placed in a batch reactor for cesium removal investigation. X-ray analysis and Fourier transform infrared spectroscopy were utilized for the evaluation of the developed adsorbent. The adsorption process has been investigated as a
[...] Read more.
Zirconia powder was synthesized via a sol gel method and placed in a batch reactor for cesium removal investigation. X-ray analysis and Fourier transform infrared spectroscopy were utilized for the evaluation of the developed adsorbent. The adsorption process has been investigated as a function of pH, contact time and temperature. The adsorption is strongly dependent on the pH of the medium whereby the removal efficiency increases as the pH turns to the alkaline range. The process was initially very fast and the maximum adsorption was attained within 60 min of contact. A pseudo-second-order model and homogeneous particle diffusion model (HPDM) were found to be the best to correlate the diffusion of cesium into the zirconia particles. Furthermore, adsorption thermodynamic parameters, namely the standard enthalpy, entropy, and Gibbs free energy, were calculated. The results indicate that cesium adsorption by zirconia is an endothermic (ΔH > 0) process and good affinity of cesium ions towards the sorbent (ΔS > 0) was observed. Full article
Figures

Figure 1

Open AccessArticle Quantitative Analysis of Major Constituents in Green Tea with Different Plucking Periods and Their Antioxidant Activity
Molecules 2014, 19(7), 9173-9186; https://doi.org/10.3390/molecules19079173
Received: 27 April 2014 / Revised: 19 June 2014 / Accepted: 23 June 2014 / Published: 1 July 2014
Cited by 34 | PDF Full-text (750 KB) | HTML Full-text | XML Full-text
Abstract
The objective of this study was to determine the relationship between the plucking periods and the major constituents and the antioxidant activity in green tea. Green tea was prepared from leaves plucked from the end of April 2013 to the end of May
[...] Read more.
The objective of this study was to determine the relationship between the plucking periods and the major constituents and the antioxidant activity in green tea. Green tea was prepared from leaves plucked from the end of April 2013 to the end of May 2013 at intervals of one week or longer. The contents of theanine, theobromine, caffeine, catechin (C), and gallocatechin gallate (GCg) were significantly decreased, whereas those of epicatechin (EC), epigallocatechin gallate (EGCg) and epigallocatechin (EGC) were significantly increased along with the period of tea leaf plucking. In addition, antioxidant activity of green tea and standard catechins was investigated using ABTS, FRAP and DPPH assays. The highest antioxidant activity was observed in relatively the oldest leaf, regardless of the assay methods used. Additionally, the order of antioxidant activity of standard catechins was as follows: EGCg ³ GCg ³ ECg > EGC ³ GC ³ EC ³ C. Moreover, the cis-catechins contents were the key factor affecting the antioxidant activity of green tea in all assays employed (ABTS, r = 0.731, p < 0.01; FRAP, r = 0.886, p < 0.01; DPPH, r = 0.778, p < 0.01). Full article
Figures

Figure 1

Open AccessArticle A Comparative Study of the Physicochemical Properties of a Virgin Coconut Oil Emulsion and Commercial Food Supplement Emulsions
Molecules 2014, 19(7), 9187-9202; https://doi.org/10.3390/molecules19079187
Received: 14 April 2014 / Revised: 19 June 2014 / Accepted: 23 June 2014 / Published: 1 July 2014
Cited by 2 | PDF Full-text (820 KB) | HTML Full-text | XML Full-text
Abstract
Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO). In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water
[...] Read more.
Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO). In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water emulsion products (C1, C2, C3, and C4). C3 exhibited the smallest droplet size of 3.25 µm. The pH for the emulsion samples ranged from 2.52 to 4.38 and thus were categorised as acidic. In a texture analysis, C2 was described as the most firm, very adhesive and cohesive, as well as having high compressibility properties. From a rheological viewpoint, all the emulsion samples exhibited non-Newtonian behaviour, which manifested as a shear-thinning property. The G'G'' crossover illustrated by the VCO emulsion in the amplitude sweep graph but not the other commercial samples illustrated that the VCO emulsion had a better mouthfeel. In this context, the VCO emulsion yielded the highest zeta potential (64.86 mV), which was attributed to its strong repulsive forces, leading to a good dispersion system. C2 comprised the highest percentage of fat among all emulsion samples, followed by the VCO emulsion, with 18.44% and 6.59%, respectively. Full article
Figures

Graphical abstract

Open AccessArticle Microwave-Assisted Kinetic Resolution of Homochiral (Z)-Cyclooct-5-ene-1,2-diol and (Z)-2-Acetoxycyclooct-4-enyl Acetate Using Lipases
Molecules 2014, 19(7), 9215-9227; https://doi.org/10.3390/molecules19079215
Received: 30 May 2014 / Revised: 21 June 2014 / Accepted: 30 June 2014 / Published: 2 July 2014
Cited by 2 | PDF Full-text (333 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Over the last decade, the use of biocatalysts has become an attractive alternative to conventional chemical methods, especially for organic synthesis, due to their unusual properties. Among these enzymes, lipases are the most widely used, because they are cheap, easily available, cofactor-free, and
[...] Read more.
Over the last decade, the use of biocatalysts has become an attractive alternative to conventional chemical methods, especially for organic synthesis, due to their unusual properties. Among these enzymes, lipases are the most widely used, because they are cheap, easily available, cofactor-free, and have broad substrate specificity. Combined to microwave heating in non-aqueous medium, recent results suggest that irradiation may influence the enzyme activity. This Communication reports the benefits of lipases and the microwave irradiation on the kinetic resolution of racemic homochiral (Z)-cyclooct-5-ene-1,2-diol and (Z)-2-acetoxycyclooct-4-enyl acetate. In order to best achieve the kinetic resolution, different parameters were studied including the type of lipase, the temperature, the impact of microwave power compared to conventional heating. Optimization of the reaction parameters lead to the obtainment of highly enriched or enantiopure diols and diesters in a clean, efficient and safe way. Full article
(This article belongs to the Special Issue ECSOC-17)
Figures

Graphical abstract

Open AccessCommunication Mechanistic Insight into CM18-Tat11 Peptide Membrane-Perturbing Action by Whole-Cell Patch-Clamp Recording
Molecules 2014, 19(7), 9228-9239; https://doi.org/10.3390/molecules19079228
Received: 30 April 2014 / Revised: 25 June 2014 / Accepted: 30 June 2014 / Published: 2 July 2014
Cited by 3 | PDF Full-text (5317 KB) | HTML Full-text | XML Full-text
Abstract
The membrane-destabilization properties of the recently-introduced endosomolytic CM18-Tat11 hybrid peptide (KWKLFKKIGAVLKVLTTG-YGRKKRRQRRR, residues 1–7 of cecropin-A, 2–12 of melittin, and 47–57 of HIV-1 Tat protein) are investigated in CHO-K1 cells by using the whole-cell configuration of the patch-clamp technique. CM18
[...] Read more.
The membrane-destabilization properties of the recently-introduced endosomolytic CM18-Tat11 hybrid peptide (KWKLFKKIGAVLKVLTTG-YGRKKRRQRRR, residues 1–7 of cecropin-A, 2–12 of melittin, and 47–57 of HIV-1 Tat protein) are investigated in CHO-K1 cells by using the whole-cell configuration of the patch-clamp technique. CM18-Tat11, CM18, and Tat11 peptides are administered to the cell membrane with a computer-controlled micro-perfusion system. CM18-Tat11 induces irreversible cell-membrane permeabilization at concentrations (≥4 µM) at which CM18 triggers transient pore formation, and Tat11 does not affect membrane integrity. We argue that the addition of the Tat11 module to CM18 is able to trigger a shift in the mechanism of membrane destabilization from “toroidal” to “carpet”, promoting a detergent-like membrane disruption. Collectively, these results rationalize previous observations on CM18-Tat11 delivery properties that we believe can guide the engineering of new modular peptides tailored to specific cargo-delivery applications. Full article
(This article belongs to the Special Issue Peptide Chemistry)
Figures

Graphical abstract

Open AccessArticle The Effect of Some 4,2 and 5,2 Bisthiazole Derivatives on Nitro-Oxidative Stress and Phagocytosis in Acute Experimental Inflammation
Molecules 2014, 19(7), 9240-9256; https://doi.org/10.3390/molecules19079240
Received: 12 May 2014 / Revised: 24 June 2014 / Accepted: 27 June 2014 / Published: 2 July 2014
Cited by 7 | PDF Full-text (645 KB) | HTML Full-text | XML Full-text
Abstract
Nineteen bisthiazoles were tested in order to assess their anti-inflammatory and antioxidant properties. First, we evaluated the in vitro direct antioxidant capacity of the bisthiazoles using the DPPH radical scavenging method. Then, the anti-inflammatory effect was tested in acute rat experimental inflammation by
[...] Read more.
Nineteen bisthiazoles were tested in order to assess their anti-inflammatory and antioxidant properties. First, we evaluated the in vitro direct antioxidant capacity of the bisthiazoles using the DPPH radical scavenging method. Then, the anti-inflammatory effect was tested in acute rat experimental inflammation by measuring the acute phase bone marrow response, the phagocytic capacity and the serum nitro-oxidative stress status. Although none of the substances showed significant direct antioxidant potential in the DPPH assay, most of them improved serum oxidative status, when administered to rats with inflammation. Four of the bisthiazoles proved to have good anti-inflammatory properties, similar or superior to that of equal doses meloxicam. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Protective Effects of Baccharis dracunculifolia Leaves Extract against Carbon Tetrachloride- and Acetaminophen-Induced Hepatotoxicity in Experimental Animals
Molecules 2014, 19(7), 9257-9272; https://doi.org/10.3390/molecules19079257
Received: 14 May 2014 / Revised: 25 June 2014 / Accepted: 26 June 2014 / Published: 2 July 2014
Cited by 8 | PDF Full-text (576 KB) | HTML Full-text | XML Full-text
Abstract
In this work we investigated the in vivo protective effects of Baccharis dracunculifolia leaves extract (BdE) against carbon tetrachloride (CCl4)- and acetaminophen (APAP)-induced hepatotoxicity. Total phenolic content, total flavonoid content, antioxidant DPPH radical scavenging activity, and HPLC analysis were performed. Our
[...] Read more.
In this work we investigated the in vivo protective effects of Baccharis dracunculifolia leaves extract (BdE) against carbon tetrachloride (CCl4)- and acetaminophen (APAP)-induced hepatotoxicity. Total phenolic content, total flavonoid content, antioxidant DPPH radical scavenging activity, and HPLC analysis were performed. Our results showed that pretreatment with BdE significantly reduced the damage caused by CCl4 and APAP on the serum markers of hepatic injury, AST, ALT, and ALP. Results were confirmed by histopathological analysis. Phytochemical analysis, performed by HPLC, showed that BdE was rich in p-coumaric acid derivatives, caffeoylquinic acids and flavonoids. BdE also showed DPPH antioxidant activity (EC50 of 15.75 ± 0.43 μg/mL), and high total phenolic (142.90 ± 0.77 mg GAE/g) and flavonoid (51.47 ± 0.60 mg RE/g) contents. This study indicated that B. dracunculifolia leaves extract has relevant in vivo hepatoprotective properties. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Graphical abstract

Open AccessArticle Chitosan-Coated Magnetic Nanoparticles Prepared in One-Step by Precipitation in a High-Aqueous Phase Content Reverse Microemulsion
Molecules 2014, 19(7), 9273-9287; https://doi.org/10.3390/molecules19079273
Received: 27 May 2014 / Revised: 25 June 2014 / Accepted: 25 June 2014 / Published: 2 July 2014
Cited by 7 | PDF Full-text (849 KB) | HTML Full-text | XML Full-text
Abstract
Chitosan-coated magnetic nanoparticles (CMNP) were prepared in one-step by precipitation in a high-aqueous phase content reverse microemulsion in the presence of chitosan. The high-aqueous phase concentration led to productivities close to 0.49 g CMNP/100 g microemulsion; much higher than those characteristic of precipitation
[...] Read more.
Chitosan-coated magnetic nanoparticles (CMNP) were prepared in one-step by precipitation in a high-aqueous phase content reverse microemulsion in the presence of chitosan. The high-aqueous phase concentration led to productivities close to 0.49 g CMNP/100 g microemulsion; much higher than those characteristic of precipitation in reverse microemulsions for preparing magnetic nanoparticles. The obtained nanoparticles present a narrow particle size distribution with an average diameter of 4.5 nm; appearing to be formed of a single crystallite; furthermore they present superparamagnetism and high magnetization values; close to 49 emu/g. Characterization of CMNP suggests that chitosan is present as a non-homogeneous very thin layer; which explains the slight reduction in the magnetization value of CMNP in comparison with that of uncoated magnetic nanoparticles. The prepared nanoparticles show high heavy ion removal capability; as demonstrated by their use in the treatment of Pb2+ aqueous solutions; from which lead ions were completely removed within 10 min. Full article
(This article belongs to the Special Issue Bio and Nanomaterials Based on Fe3O4)
Figures

Figure 1

Open AccessArticle Ni-Catalyzed Homoallylation of Polyhydroxy N,O-Acetals with Conjugated Dienes Promoted by Triethylborane
Molecules 2014, 19(7), 9288-9306; https://doi.org/10.3390/molecules19079288
Received: 4 April 2014 / Revised: 13 June 2014 / Accepted: 23 June 2014 / Published: 2 July 2014
Cited by 2 | PDF Full-text (299 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In the presence of Ni-catalyst and triethylborane, N,O-acetals prepared from glycolaldehyde and glyceraldehyde with primary amines in situ underwent homoallylation with conjugated dienes to provide 2-amino-5-hexenols in high regio- and stereoselectivity. Under similar reaction conditions, N,O-acetals from
[...] Read more.
In the presence of Ni-catalyst and triethylborane, N,O-acetals prepared from glycolaldehyde and glyceraldehyde with primary amines in situ underwent homoallylation with conjugated dienes to provide 2-amino-5-hexenols in high regio- and stereoselectivity. Under similar reaction conditions, N,O-acetals from carbohydrates with primary amines provided the corresponding polyhydroxy-bishomoallylamines in good to reasonable yields. Full article
(This article belongs to the Special Issue Dynamic Stereochemistry)
Figures

Figure 1

Open AccessArticle N-Alkyl Carbazole Derivatives as New Tools for Alzheimer’s Disease: Preliminary Studies
Molecules 2014, 19(7), 9307-9317; https://doi.org/10.3390/molecules19079307
Received: 8 May 2014 / Revised: 12 June 2014 / Accepted: 24 June 2014 / Published: 2 July 2014
Cited by 14 | PDF Full-text (555 KB) | HTML Full-text | XML Full-text
Abstract
Alzheimer’s disease (AD) is a progressive and age-related neurodegenerative disorder affecting brain cells and is the most common form of “dementia”, because of the cognitive detriment which takes place. Neuronal disruption represents its major feature, due to the cytosolic accumulation of amyloid β-peptide
[...] Read more.
Alzheimer’s disease (AD) is a progressive and age-related neurodegenerative disorder affecting brain cells and is the most common form of “dementia”, because of the cognitive detriment which takes place. Neuronal disruption represents its major feature, due to the cytosolic accumulation of amyloid β-peptide (Aβ) which leads to senile plaques formation and intracellular neurofibrillary tangles. Many studies have focused on the design and therapeutic use of new molecules able to inhibit Aβ aggregation. In this context, we evaluated the ability of two recently synthesized series of N-alkyl carbazole derivatives to increase the Aβ soluble forms, through molecular docking simulations and in vitro experiments. Our data evidenced that two carbazole derivatives, the most active, adopt distinct binding modes involving key residues for Aβ fibrillization. They exhibit a good interfering activity on Aβ aggregation in mouse (N2a) cells, stably expressing wild-type human amyloid precursor protein (APP) 695. These preliminary results are promising and we are confident that the N-alkyl carbazole derivatives may encourage next future studies needed for enlarging the knowledge about the AD disease approach. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle New Potentially Active Pyrazinamide Derivatives Synthesized Under Microwave Conditions
Molecules 2014, 19(7), 9318-9338; https://doi.org/10.3390/molecules19079318
Received: 30 May 2014 / Revised: 17 June 2014 / Accepted: 26 June 2014 / Published: 3 July 2014
Cited by 4 | PDF Full-text (419 KB) | HTML Full-text | XML Full-text
Abstract
A series of 18 N-alkyl substituted 3-aminopyrazine-2-carboxamides was prepared in this work according to previously experimentally set and proven conditions using microwave assisted synthesis methodology. This approach for the aminodehalogenation reaction was chosen due to higher yields and shorter reaction times compared
[...] Read more.
A series of 18 N-alkyl substituted 3-aminopyrazine-2-carboxamides was prepared in this work according to previously experimentally set and proven conditions using microwave assisted synthesis methodology. This approach for the aminodehalogenation reaction was chosen due to higher yields and shorter reaction times compared to organic reactions with conventional heating. Antimycobacterial, antibacterial, antifungal and photosynthetic electron transport (PET) inhibiting in vitro activities of these compounds were investigated. Experiments for the determination of lipophilicity were also performed. Only a small number of substances with alicyclic side chain showed activity against fungi which was the same or higher than standards and the biological efficacy of the compounds increased with rising lipophilicity. Nine pyrazinamide derivatives also inhibited PET in spinach chloroplasts and the IC50 values of these compounds varied in the range from 14.3 to 1590.0 μmol/L. The inhibitory activity was connected not only with the lipophilicity, but also with the presence of secondary amine fragment bounded to the pyrazine ring. Structure-activity relationships are discussed as well. Full article
(This article belongs to the Special Issue ECSOC-17)
Figures

Figure 1

Open AccessArticle Synthesis and Pharmacological Evaluation of Modified Adenosines Joined to Mono-Functional Platinum Moieties
Molecules 2014, 19(7), 9339-9353; https://doi.org/10.3390/molecules19079339
Received: 26 March 2014 / Revised: 23 June 2014 / Accepted: 25 June 2014 / Published: 3 July 2014
Cited by 6 | PDF Full-text (392 KB) | HTML Full-text | XML Full-text
Abstract
The synthesis of four novel platinum complexes, bearing N6-(6-amino-hexyl)adenosine or a 1,6-di(adenosin-N6-yl)-hexane respectively, as ligands of mono-functional cisplatin or monochloro(ethylendiamine)platinum(II), is reported. The chemistry exploits the high affinity of the charged platinum centres towards the N7 position of
[...] Read more.
The synthesis of four novel platinum complexes, bearing N6-(6-amino-hexyl)adenosine or a 1,6-di(adenosin-N6-yl)-hexane respectively, as ligands of mono-functional cisplatin or monochloro(ethylendiamine)platinum(II), is reported. The chemistry exploits the high affinity of the charged platinum centres towards the N7 position of the adenosine base system and a primary amine of an alkyl chain installed on the C6 position of the purine. The cytotoxic behaviour of the synthesized complexes has been studied in A549 adenocarcinomic human alveolar basal epithelial and MCF7 human breast adenocarcinomic cancer cell lines, in order to investigate their effects on cell viability and proliferation. Full article
(This article belongs to the Special Issue Practical Applications of Metal Complexes)
Figures

Graphical abstract

Open AccessArticle Intramolecular Hydrogen Bond in Biologically Active o-Carbonyl Hydroquinones
Molecules 2014, 19(7), 9354-9368; https://doi.org/10.3390/molecules19079354
Received: 9 May 2014 / Revised: 18 June 2014 / Accepted: 27 June 2014 / Published: 3 July 2014
Cited by 14 | PDF Full-text (1081 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Intramolecular hydrogen bonds (IHBs) play a central role in the molecular structure, chemical reactivity and interactions of biologically active molecules. Here, we study the IHBs of seven related o-carbonyl hydroquinones and one structurally-related aromatic lactone, some of which have shown anticancer and
[...] Read more.
Intramolecular hydrogen bonds (IHBs) play a central role in the molecular structure, chemical reactivity and interactions of biologically active molecules. Here, we study the IHBs of seven related o-carbonyl hydroquinones and one structurally-related aromatic lactone, some of which have shown anticancer and antioxidant activity. Experimental NMR data were correlated with theoretical calculations at the DFT and ab initio levels. Natural bond orbital (NBO) and molecular electrostatic potential (MEP) calculations were used to study the electronic characteristics of these IHB. As expected, our results show that NBO calculations are better than MEP to describe the strength of the IHBs. NBO energies (∆Eij(2)) show that the main contributions to energy stabilization correspond to LPàσ* interactions for IHBs, O1O2-H2 and the delocalization LPàπ* for O2-C2 = Cα(β). For the O1O2-H2 interaction, the values of ∆Eij(2) can be attributed to the difference in the overlap ability between orbitals i and j (Fij), instead of the energy difference between them. The large energy for the LP O2àπ* C2 = Cα(β) interaction in the compounds 9-Hydroxy-5-oxo-4,8, 8-trimethyl-l,9(8H)-anthracenecarbolactone (VIII) and 9,10-dihydroxy-4,4-dimethylanthracen-1(4H)-one (VII) (55.49 and 60.70 kcal/mol, respectively) when compared with the remaining molecules (all less than 50 kcal/mol), suggests that the IHBs in VIII and VII are strongly resonance assisted. Full article
(This article belongs to the Special Issue Intramolecular Hydrogen Bonding)
Figures

Graphical abstract

Open AccessArticle Determination of Phenol Compounds In Surface Water Matrices by Bar Adsorptive Microextraction-High Performance Liquid Chromatography-Diode Array Detection
Molecules 2014, 19(7), 9369-9379; https://doi.org/10.3390/molecules19079369
Received: 13 March 2014 / Revised: 26 June 2014 / Accepted: 27 June 2014 / Published: 3 July 2014
Cited by 5 | PDF Full-text (277 KB) | HTML Full-text | XML Full-text
Abstract
Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of trace levels of five phenol compounds (3-nitrophenol, 4-nitrophenol, bisphenol-A, 4-n-octylphenol and 4-n-nonylphenol) in surface water
[...] Read more.
Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of trace levels of five phenol compounds (3-nitrophenol, 4-nitrophenol, bisphenol-A, 4-n-octylphenol and 4-n-nonylphenol) in surface water matrices. By using a polystyrene-divinylbenzene copolymer (PS-DVB) sorbent phase, high selectivity and efficiency is achieved even against polydimethylsiloxane through stir bar sorptive extraction. Assays performed by BAµE(PS-DVB)-LD/HPLC-DAD on 25 mL water samples spiked at the 10.0 µg/L levels yielded recoveries over 88.0% ± 5.7% for all five analytes, under optimized experimental conditions. The analytical performance showed good precision (RSD < 15%), detection limits of 0.25 µg/L and linear dynamic ranges (1.0–25.0 μg/L) with determination coefficient higher than 0.9904. By using the standard addition method, the application of the present method to surface water matrices allowed very good performances at the trace level. The proposed methodology proved to be a suitable alternative to monitor phenol compounds in surface water matrices, showing to be easy to implement, reliable, sensitive and requiring a low sample volume. Full article
(This article belongs to the Special Issue Microextraction)
Figures

Figure 1

Open AccessArticle Antioxidant Activity and Acetylcholinesterase Inhibition of Grape Skin Anthocyanin (GSA)
Molecules 2014, 19(7), 9403-9418; https://doi.org/10.3390/molecules19079403
Received: 25 April 2014 / Revised: 18 June 2014 / Accepted: 28 June 2014 / Published: 3 July 2014
Cited by 14 | PDF Full-text (421 KB) | HTML Full-text | XML Full-text
Abstract
We aimed to investigate the antioxidant and acetylcholinesterase inhibitory activities of the anthocyanin rich extract of grape skin. Grape skin anthocyanin (GSA) neutralized free radicals in different test systems, such as 2,-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, to form complexes with Fe
[...] Read more.
We aimed to investigate the antioxidant and acetylcholinesterase inhibitory activities of the anthocyanin rich extract of grape skin. Grape skin anthocyanin (GSA) neutralized free radicals in different test systems, such as 2,-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, to form complexes with Fe2+ preventing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis and oxidative DNA damage. Moreover, GSA decreased reactive oxygen species (ROS) generation in isolated mitochondria thus inhibiting 2',-7'-dichlorofluorescin (DCFH) oxidation. In an in vivo study, female BALB/c mice were administered GSA, at 12.5, 25, and 50 mg per kg per day orally for 30 consecutive days. Herein, we demonstrate that GSA administration significantly elevated the level of antioxidant enzymes in mice sera, livers, and brains. Furthermore, GSA inhibited acetylcholinesterase (AChE) in the in vitro assay with an IC50 value of 363.61 µg/mL. Therefore, GSA could be an excellent source of antioxidants and its inhibition of cholinesterase is of interest with regard to neurodegenerative disorders such as Alzheimer’s disease. Full article
(This article belongs to the Special Issue Anthocyanins) Printed Edition available
Figures

Figure 1

Open AccessArticle Synthesis, Spectroscopic and Theoretical Studies of New Dimeric Quaternary Alkylammonium Conjugates of Sterols
Molecules 2014, 19(7), 9419-9434; https://doi.org/10.3390/molecules19079419
Received: 10 June 2014 / Revised: 30 June 2014 / Accepted: 1 July 2014 / Published: 3 July 2014
Cited by 3 | PDF Full-text (704 KB) | HTML Full-text | XML Full-text
Abstract
New dimeric quaternary alkylammonium conjugates of sterols were obtained by two step reactions of ergosterol, cholesterol and cholestanol with bromoacetic acid bromide, followed by bimolecular nucleophilic substitution with N,N,N',N'-tetramethyl-1,3-propanediamine, N,N,N',N''
[...] Read more.
New dimeric quaternary alkylammonium conjugates of sterols were obtained by two step reactions of ergosterol, cholesterol and cholestanol with bromoacetic acid bromide, followed by bimolecular nucleophilic substitution with N,N,N',N'-tetramethyl-1,3-propanediamine, N,N,N',N'',N''-pentamethyldiethylenetriamine and 3,3'-iminobis- (N,N-dimethylpropylamine). The product structures were confirmed by spectral (1H-NMR, 13C-NMR, FT-IR) analysis, mass spectrometry (ESI-MS) and PM5 semiempirical methods. Additionally in silico studies have been conducted for the synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS). Full article
(This article belongs to the Section Organic Chemistry)
Figures

Figure 1

Open AccessArticle GSK3β Regulates Milk Synthesis in and Proliferation of Dairy Cow Mammary Epithelial Cells via the mTOR/S6K1 Signaling Pathway
Molecules 2014, 19(7), 9435-9452; https://doi.org/10.3390/molecules19079435
Received: 16 May 2014 / Revised: 22 June 2014 / Accepted: 27 June 2014 / Published: 3 July 2014
Cited by 20 | PDF Full-text (502 KB) | HTML Full-text | XML Full-text
Abstract
Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase, whose activity is inhibited by AKT phosphorylation. This inhibitory phosphorylation of GSK3β can in turn play a regulatory role through phosphorylation of several proteins (such as mTOR, elF2B) to promote protein synthesis. mTOR is
[...] Read more.
Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase, whose activity is inhibited by AKT phosphorylation. This inhibitory phosphorylation of GSK3β can in turn play a regulatory role through phosphorylation of several proteins (such as mTOR, elF2B) to promote protein synthesis. mTOR is a key regulator in protein synthesis and cell proliferation, and recent studies have shown that both GSK3β and mTORC1 can regulate SREBP1 to promote fat synthesis. Thus far, however, the cross talk between GSK3β and the mTOR pathway in the regulation of milk synthesis and associated cell proliferation is not well understood. In this study the interrelationship between GSK3β and the mTOR/S6K1 signaling pathway leading to milk synthesis and proliferation of dairy cow mammary epithelial cells (DCMECs) was analyzed using techniques including GSK3β overexpression by transfection, GSK3β inhibition, mTOR inhibition and methionine stimulation. The analyses revealed that GSK3β represses the mTOR/S6K1 pathway leading to milk synthesis and cell proliferation of DCMECs, whereas GSK3β phosphorylation enhances this pathway. Conversely, the activated mTOR/S6K1 signaling pathway downregulates GSK3β expression but enhances GSK3β phosphorylation to increase milk synthesis and cell proliferation, whereas inhibition of mTOR leads to upregulation of GSK3β and repression of GSK3β phosphorylation, which in turn decreases milk synthesis, and cell proliferation. These findings indicate that GSK3β and phosphorylated GSK3β regulate milk synthesis and proliferation of DCMECs via the mTOR/S6K1 signaling pathway. These findings provide new insight into the mechanisms of milk synthesis. Full article
Figures

Figure 1

Open AccessArticle Tanacetum polycephalum (L.) Schultz-Bip. Induces Mitochondrial-Mediated Apoptosis and Inhibits Migration and Invasion in MCF7 Cells
Molecules 2014, 19(7), 9478-9501; https://doi.org/10.3390/molecules19079478
Received: 13 May 2014 / Revised: 6 June 2014 / Accepted: 23 June 2014 / Published: 3 July 2014
Cited by 9 | PDF Full-text (4893 KB) | HTML Full-text | XML Full-text
Abstract
Tanacetum polycephalum (L.) Schultz-Bip (Mokhaleseh) has been traditionally used in the treatment of headaches, migraines, hyperlipidemia and diabetes. The present study aimed to evaluate its anticancer properties and possible mechanism of action using MCF7 as an in vitro model. T. polycephalum leaves were
[...] Read more.
Tanacetum polycephalum (L.) Schultz-Bip (Mokhaleseh) has been traditionally used in the treatment of headaches, migraines, hyperlipidemia and diabetes. The present study aimed to evaluate its anticancer properties and possible mechanism of action using MCF7 as an in vitro model. T. polycephalum leaves were extracted using hexane, chloroform and methanol solvents and the cytotoxicity was evaluated using the MTT assay. Detection of the early apoptotic cells was investigated using acridine orange/propidium iodide staining. An Annexin-V-FITC assay was carried out to observe the phosphatidylserine externalization as a marker for apoptotic cells. High content screening was applied to analyze the cell membrane permeability, nuclear condensation, mitochondrial membrane potential (MMP) and cytochrome c release. Apoptosis was confirmed by using caspase-8, caspase-9 and DNA laddering assays. In addition, Bax/Bcl-2 expressions and cell cycle arrest also have been investigated. MTT assay revealed significant cytotoxicity of T. Polycephalum hexane extract (TPHE) on MCF7 cells with the IC50 value of 6.42 ± 0.35 µg/mL. Significant increase in chromatin condensation was also observed via fluorescence analysis. Treatment of MCF7 cells with TPHE encouraged apoptosis through reduction of MMP by down-regulation of Bcl-2 and up-regulation of Bax, triggering the cytochrome c leakage from mitochondria to the cytosol. The treated MCF7 cells significantly arrested at G1 phase. The chromatographic analysis elicited that the major active compound in this extract is 8β-hydroxy-4β,15-dihydrozaluzanin C. Taken together, the results presented in this study demonstrated that the hexane extract of T. Polycephalum inhibits the proliferation of MCF7 cells, resulting in the cell cycle arrest and apoptosis, which was explained to be through the mitochondrial pathway. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Effects of Icariin on Reproductive Functions in Male Rats
Molecules 2014, 19(7), 9502-9514; https://doi.org/10.3390/molecules19079502
Received: 25 April 2014 / Revised: 18 June 2014 / Accepted: 24 June 2014 / Published: 3 July 2014
Cited by 12 | PDF Full-text (1728 KB) | HTML Full-text | XML Full-text
Abstract
The present study investigated the effects and potential mechanism(s) of action of icariin on the reproductive functions of male rats. Adult rats were treated orally with icariin at doses of 0 (control), 50, 100, or 200 mg/kg body weight for 35 consecutive days.
[...] Read more.
The present study investigated the effects and potential mechanism(s) of action of icariin on the reproductive functions of male rats. Adult rats were treated orally with icariin at doses of 0 (control), 50, 100, or 200 mg/kg body weight for 35 consecutive days. The results show that icariin had virtually no effect on the body weight or organ coefficients of the testes or epididymides. However, 100 mg/kg icariin significantly increased epididymal sperm counts. In addition, 50 and 100 mg/kg icariin significantly increased testosterone levels. Real-time PCR suggests icariin may be involved in testosterone production via mRNA expression regulation of genes such as peripheral type benzodiazepine receptor (PBR) and steroidogenic acute regulatory protein (StAR). Furthermore, 100 mg/kg icariin treatment also affected follicle stimulating hormone receptor (FSHR) and claudin-11 mRNA expression in Sertoli cells. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were measured in the testes; 50 and 100 mg/kg icariin treatment improved antioxidative capacity, while 200 mg/kg icariin treatment upregulated oxidative stress. These results collectively suggest that icariin within a certain dose range is beneficial to male reproductive functions; meanwhile, higher doses of icariin may damage reproductive functions by increasing oxidative stress in the testes. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessArticle Studies on Cytotoxic Constituents from the Leaves of Elaeagnus oldhamii Maxim. in Non-Small Cell Lung Cancer A549 Cells
Molecules 2014, 19(7), 9515-9534; https://doi.org/10.3390/molecules19079515
Received: 29 April 2014 / Revised: 15 June 2014 / Accepted: 25 June 2014 / Published: 4 July 2014
Cited by 28 | PDF Full-text (314 KB) | HTML Full-text | XML Full-text
Abstract
Elaeagnus oldhamii Maxim. is a commonly used traditional herbal medicine. In Taiwan the leaves of E. oldhamii Maxim. are mainly used for treating lung disorders. Twenty five compounds were isolated from the leaves of E. oldhamii Maxim. in the present study. These
[...] Read more.
Elaeagnus oldhamii Maxim. is a commonly used traditional herbal medicine. In Taiwan the leaves of E. oldhamii Maxim. are mainly used for treating lung disorders. Twenty five compounds were isolated from the leaves of E. oldhamii Maxim. in the present study. These included oleanolic acid (1), 3-O-(Z)-coumaroyl oleanolic acid (2), 3-O-(E)-coumaroyl oleanolic acid (3), 3-O-caffeoyl oleanolic acid (4), ursolic acid (5), 3-O-(Z)-coumaroyl ursolic acid (6), 3-O-(E)-coumaroyl ursolic acid (7), 3-O-caffeoyl ursolic acid (8), 3β, 13β-dihydroxyolean-11-en-28-oic acid (9), 3β, 13β-dihydroxyurs-11-en-28-oic acid (10), uvaol (11), betulin (12), lupeol (13), kaempferol (14), aromadendrin (15), epigallocatechin (16), cis-tiliroside (17), trans-tiliroside (18), isoamericanol B (19), trans-p-coumaric acid (20), protocatechuic acid (21), salicylic acid (22), trans-ferulic acid (23), syringic acid (24) and 3-O-methylgallic acid (25). Of the 25 isolated compounds, 21 compounds were identified for the first time in E. oldhamii Maxim. These included compounds 1, 4, 5 and 825. These 25 compounds were evaluated for their inhibitory activity against the growth of non-small cell lung cancer A549 cells by the MTT assay, and the corresponding structure-activity relationships were discussed. Among these 25 compounds, compound 6 displayed the best activity against the A549 cell line in vitro (CC50 = 8.56 ± 0.57 μg/mL, at 48 h of MTT asssay). Furthermore, compound 2, 4, 8 and 18 exhibited in vitro cytotoxicity against the A549 cell line with the CC50 values of less than 20 μg/mL at 48 h of MTT asssay. These five compounds 2, 4, 6, 8 and 18 exhibited better cytotoxic activity compared with cisplatin (positive control, CC50 value of 14.87 ± 1.94 μg/mL, at 48 h of MTT asssay). The result suggested that the five compounds might be responsible for its clinical anti-lung cancer effect. Full article
Figures

Figure 1

Open AccessArticle Secondary Metabolite Profiling of Curcuma Species Grown at Different Locations Using GC/TOF and UPLC/Q-TOF MS
Molecules 2014, 19(7), 9535-9551; https://doi.org/10.3390/molecules19079535
Received: 16 April 2014 / Revised: 26 June 2014 / Accepted: 30 June 2014 / Published: 4 July 2014
Cited by 19 | PDF Full-text (686 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Curcuma, a genus of rhizomatous herbaceous species, has been used as a spice, traditional medicine, and natural dye. In this study, the metabolite profile of Curcuma extracts was determined using gas chromatography-time of flight mass spectrometry (GC/TOF MS) and ultrahigh-performance liquid chromatography–quadrupole
[...] Read more.
Curcuma, a genus of rhizomatous herbaceous species, has been used as a spice, traditional medicine, and natural dye. In this study, the metabolite profile of Curcuma extracts was determined using gas chromatography-time of flight mass spectrometry (GC/TOF MS) and ultrahigh-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) to characterize differences between Curcuma aromatica and Curcuma longa grown on the Jeju-do or Jin-do islands, South Korea. Previous studies have performed primary metabolite profiling of Curcuma species grown in different regions using NMR-based metabolomics. This study focused on profiling of secondary metabolites from the hexane extract of Curcuma species. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) plots showed significant differences between the C. aromatica and C. longa metabolite profiles, whereas geographical location had little effect. A t-test was performed to identify statistically significant metabolites, such as terpenoids. Additionally, targeted profiling using UPLC/Q-TOF MS showed that the concentration of curcuminoids differed depending on the plant origin. Based on these results, a combination of GC- and LC-MS allowed us to analyze curcuminoids and terpenoids, the typical bioactive compounds of Curcuma, which can be used to discriminate Curcuma samples according to species or geographical origin. Full article
(This article belongs to the Section Metabolites)
Figures

Graphical abstract

Open AccessArticle Formation of a Flavin-Linked Peptide
Molecules 2014, 19(7), 9552-9561; https://doi.org/10.3390/molecules19079552
Received: 27 May 2014 / Revised: 2 July 2014 / Accepted: 2 July 2014 / Published: 4 July 2014
PDF Full-text (501 KB) | HTML Full-text | XML Full-text
Abstract
In a previous study, we showed that formylmethylflavin (FMF) can bind to cysteine. In this study, FMF was reacted with native peptides (CG and CKLVFF) containing an N-terminal cysteine. The formation of flavin-CG and flavin-CKLVFF was confirmed using HPLC and ESI-MS. Storage of
[...] Read more.
In a previous study, we showed that formylmethylflavin (FMF) can bind to cysteine. In this study, FMF was reacted with native peptides (CG and CKLVFF) containing an N-terminal cysteine. The formation of flavin-CG and flavin-CKLVFF was confirmed using HPLC and ESI-MS. Storage of flavin-CKLVFF in DMSO at −30 °C for 7 days resulted in no detectable deposition. In contrast, flavin-CKLVFF formed deposits when stored in water at −30 °C for 1 day, but no deposit was observed in the aqueous solution of flavin-CKLVFF after 7 days storage in the presence of 0.1% Triton X-100. Full article
(This article belongs to the Special Issue ECSOC-17)
Figures

Graphical abstract

Open AccessArticle Combined Effects of Ultrasound and Immobilization Protocol on Butyl Acetate Synthesis Catalyzed by CALB
Molecules 2014, 19(7), 9562-9576; https://doi.org/10.3390/molecules19079562
Received: 26 May 2014 / Revised: 30 June 2014 / Accepted: 1 July 2014 / Published: 7 July 2014
Cited by 21 | PDF Full-text (457 KB) | HTML Full-text | XML Full-text
Abstract
It is well established that the performance of lipase B from Candida antarctica (CALB) as catalyst for esterification reactions may be improved by the use of ultrasound technology or by its immobilization on styrene-divinylbenzene beads (MCI-CALB). The present research evaluated the synthesis of
[...] Read more.
It is well established that the performance of lipase B from Candida antarctica (CALB) as catalyst for esterification reactions may be improved by the use of ultrasound technology or by its immobilization on styrene-divinylbenzene beads (MCI-CALB). The present research evaluated the synthesis of butyl acetate using MCI-CALB under ultrasonic energy, comparing the results against those obtained using the commercial preparation, Novozym 435. The optimal conditions were determined using response surface methodology (RSM) evaluating the following parameters: reaction temperature, substrate molar ratio, amount of biocatalyst, and added water. The optimal conditions for butyl acetate synthesis catalyzed by MCI-CALB were: temperature, 48.8 °C; substrate molar ratio, 3.46:1 alcohol:acid; amount of biocatalyst, 7.5%; and added water 0.28%, both as substrate mass. Under these conditions, 90% of conversion was reached in 1.5 h. In terms of operational stability, MCI-CALB was reused in seven cycles while keeping 70% of its initial activity under ultrasonic energy. The support pore size and resistance are key points for the enzyme activity and stability under mechanical stirring. The use of ultrasound improved both activity and stability because of better homogeneity and reduced mechanical stress to the immobilized system. Full article
(This article belongs to the Special Issue Enzyme Immobilization)
Figures

Graphical abstract

Open AccessArticle Quantification of the Resveratrol Analogs trans-2,3-Dimethoxy-stilbene and trans-3,4-Dimethoxystilbene in Rat Plasma: Application to Pre-Clinical Pharmacokinetic Studies
Molecules 2014, 19(7), 9577-9590; https://doi.org/10.3390/molecules19079577
Received: 4 May 2014 / Revised: 26 June 2014 / Accepted: 28 June 2014 / Published: 7 July 2014
Cited by 2 | PDF Full-text (821 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
trans-2,3-Dimethoxystilbene (2,3-DMS) and trans-3,4-dimethoxystilbene (3,4-DMS) are two synthetic resveratrol (trans-3,5,4'-trihydroxystilbene) analogs. In this study, a simple HPLC method was developed and validated to determine 2,3-DMS and 3,4-DMS in rat plasma. Chromatographic separation was obtained with a reversed-phase HPLC column
[...] Read more.
trans-2,3-Dimethoxystilbene (2,3-DMS) and trans-3,4-dimethoxystilbene (3,4-DMS) are two synthetic resveratrol (trans-3,5,4'-trihydroxystilbene) analogs. In this study, a simple HPLC method was developed and validated to determine 2,3-DMS and 3,4-DMS in rat plasma. Chromatographic separation was obtained with a reversed-phase HPLC column through a 12.5-min gradient delivery of a mixture of acetonitrile and water at the flow rate of 1.5 mL/min at 50 °C. The lower limit of quantification was 10 ng/mL. After successful validation, the pharmacokinetic profiles of 2,3-DMS and 3,4-DMS were subsequently studied in Sprague-Dawley rats. Upon single intravenous administration (4 mg/kg), 2,3-DMS had a medium volume of distribution of the central compartment (Vc = 2.71 ± 0.51 L/kg), quite rapid clearance (Cl = 52.0 ± 7.0 mL/min/kg), moderate mean transit time (MTT0→last = 131.0 ± 4.5 min) but a fairly long terminal elimination half-life (t1/2 λZ = 288.9 ± 92.9 min). Interestingly, 3,4-DMS displayed a pharmacokinetic profile apparently distinct from 2,3-DMS and it had more extensive distribution (Vc = 5.58 ± 1.73 L/kg), faster clearance (Cl = 143.4 ± 40.5 mL/min/kg) and shorter residence (MTT0→last = 61.4 ± 27.1 min). Following single oral administration (10 mg/kg), 2,3-DMS had low and erratic plasma exposure (Cmax = 37.5 ± 23.7 ng/mL) and poor oral bioavailability (2.22% ± 2.13%) while the oral bioavailability of 3,4-DMS was even poorer than 2,3-DMS. Clearly, the location of the methoxy groups had a significant impact on the pharmacokinetics of resveratrol analogs. This study provided useful information for the design of resveratrol derivatives in future study. Full article
(This article belongs to the Special Issue Resveratrol)
Figures

Figure 1

Open AccessArticle Combined Kinetic Studies and Computational Analysis on Kojic Acid Analogs as Tyrosinase Inhibitors
Molecules 2014, 19(7), 9591-9605; https://doi.org/10.3390/molecules19079591
Received: 6 June 2014 / Revised: 1 July 2014 / Accepted: 2 July 2014 / Published: 7 July 2014
Cited by 8 | PDF Full-text (623 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Tyrosinase is a key enzyme in melanin synthesis and widely distributed in plants and animals tissues. In mammals, this enzyme is related to pigment production, involved in wound healing, primary immune response and it can also contribute to catecholamines synthesis in the brain.
[...] Read more.
Tyrosinase is a key enzyme in melanin synthesis and widely distributed in plants and animals tissues. In mammals, this enzyme is related to pigment production, involved in wound healing, primary immune response and it can also contribute to catecholamines synthesis in the brain. Consequently, tyrosinase enzyme represents an attractive and selective target in the field of the medicine, cosmetics and bio-insecticides. In this paper, experimental kinetics and computational analysis were used to study the inhibition of tyrosinase by analogous of Kojic acid. The main interactions occurring between inhibitors-tyrosinase complexes and the influence of divalent cation (Cu2+) in enzymatic inhibition were investigated by using molecular docking, molecular dynamic simulations and electrostatic binding free energy by using the Linear Interaction Energy (LIE) method. The results showed that the electrostatic binding free energy are correlated with values of constant inhibition (r2 = 0.97).Thus, the model obtained here could contribute to future studies of this important system and, therefore, eventually facilitate development of tyrosinase inhibitors. Full article
(This article belongs to the Section Molecular Diversity)
Figures

Figure 1

Open AccessArticle Cytotoxic and Antiproliferative Effect of Tepary Bean Lectins on C33-A, MCF-7, SKNSH, and SW480 Cell Lines
Molecules 2014, 19(7), 9610-9627; https://doi.org/10.3390/molecules19079610
Received: 4 May 2014 / Revised: 2 July 2014 / Accepted: 2 July 2014 / Published: 7 July 2014
Cited by 3 | PDF Full-text (630 KB) | HTML Full-text | XML Full-text
Abstract
For many years, several studies have been employing lectin from vegetables in order to prove its toxic effect on various cell lines. In this work, we analyzed the cytotoxic, antiproliferative, and post-incubatory effect of pure tepary bean lectins on four lines of malignant
[...] Read more.
For many years, several studies have been employing lectin from vegetables in order to prove its toxic effect on various cell lines. In this work, we analyzed the cytotoxic, antiproliferative, and post-incubatory effect of pure tepary bean lectins on four lines of malignant cells: C33-A; MCF-7; SKNSH, and SW480. The tests were carried out employing MTT and 3[H]-thymidine assays. The results showed that after 24 h of lectin exposure, the cells lines showed a dose-dependent cytotoxic effect, the effect being higher on MCF-7, while C33-A showed the highest resistance. Cell proliferation studies showed that the toxic effect induced by lectins is higher even when lectins are removed, and in fact, the inhibition of proliferation continues after 48 h. Due to the use of two techniques to analyze the cytotoxic and antiproliferative effect, differences were observed in the results, which can be explained by the fact that one technique is based on metabolic reactions, while the other is based on the 3[H]-thymidine incorporated in DNA by cells under division. These results allow concluding that lectins exert a cytotoxic effect after 24 h of exposure, exhibiting a dose-dependent effect. In some cases, the cytotoxic effect is higher even when the lectins are eliminated, however, in other cases, the cells showed a proliferative effect. Full article
Figures

Figure 1

Open AccessArticle Novel Cinnamic Acid Derivatives as Antioxidant and Anticancer Agents: Design, Synthesis and Modeling Studies
Molecules 2014, 19(7), 9655-9674; https://doi.org/10.3390/molecules19079655
Received: 5 May 2014 / Revised: 13 June 2014 / Accepted: 17 June 2014 / Published: 7 July 2014
Cited by 22 | PDF Full-text (507 KB) | HTML Full-text | XML Full-text
Abstract
Cinnamic acids have been identified as interesting compounds with antioxidant, anti-inflammatory and cytotoxic properties. In the present study, simple cinnamic acids were synthesized by Knoevenagel condensation reactions and evaluated for the above biological activities. Compound 4ii proved to be the most potent LOX
[...] Read more.
Cinnamic acids have been identified as interesting compounds with antioxidant, anti-inflammatory and cytotoxic properties. In the present study, simple cinnamic acids were synthesized by Knoevenagel condensation reactions and evaluated for the above biological activities. Compound 4ii proved to be the most potent LOX inhibitor. Phenyl- substituted acids showed better inhibitory activity against soybean LOX, and it must be noted that compounds 4i and 3i with higher lipophilicity values resulted less active than compounds 2i and 1i. The compounds have shown very good activity in different antioxidant assays. The antitumor properties of these derivatives have been assessed by their 1/IC50 inhibitory values in the proliferation of HT-29, A-549, OAW-42, MDA-MB-231, HeLa and MRC-5 normal cell lines. The compounds presented low antitumor activity considering the IC50 values attained for the cell lines, with the exception of compound 4ii. Molecular docking studies were carried out on cinnamic acid derivative 4ii and were found to be in accordance with our experimental biological results. Full article
(This article belongs to the Special Issue Natural Antioxidants and Ageing)
Figures

Graphical abstract

Open AccessArticle Characterization of Phytochemicals and Antioxidant Activities of Red Radish Brines during Lactic Acid Fermentation
Molecules 2014, 19(7), 9675-9688; https://doi.org/10.3390/molecules19079675
Received: 30 May 2014 / Revised: 24 June 2014 / Accepted: 27 June 2014 / Published: 7 July 2014
Cited by 5 | PDF Full-text (637 KB) | HTML Full-text | XML Full-text
Abstract
Red radish (Raphanus L.) pickles are popular appetizers or spices in Asian-style cuisine. However, tons of radish brines are generated as wastes from industrial radish pickle production. In this study, we evaluated the dynamic changes in colour properties, phenolics, anthocyanin profiles, phenolic
[...] Read more.
Red radish (Raphanus L.) pickles are popular appetizers or spices in Asian-style cuisine. However, tons of radish brines are generated as wastes from industrial radish pickle production. In this study, we evaluated the dynamic changes in colour properties, phenolics, anthocyanin profiles, phenolic acid composition, flavonoids, and antioxidant properties in radish brines during lactic acid fermentation. The results showed that five flavonoids detected were four anthocyanins and one kaempferol derivative, including pelargonidin-3-digluoside-5-glucoside derivatives acylated with p-coumaric acid, ferulic acid, p-coumaric and manolic acids, or ferulic and malonic acids. Amounts ranged from 15.5–19.3 µg/mL in total monomeric anthocyanins, and kaempferol-3,7-diglycoside (15–30 µg/mL). 4-Hydroxy-benzoic, gentisic, vanillic, syringic, p-coumaric, ferulic, sinapic and salicylic acids were detected in amounts that varied from 70.2–92.2 µg/mL, whereas the total phenolic content was 206–220 µg/mL. The change in colour of the brine was associated with the accumulation of lactic acid and anthocyanins. The ORAC and Fe2+ chelation capacity of radish brines generally decreased, whereas the reducing power measured as FRAP values was increased during the fermentation from day 5 to day 14. This study provided information on the phytochemicals and the antioxidative activities of red radish fermentation waste that might lead to further utilization as nutraceuticals or natural colorants. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessArticle Ionic Liquid-Based Vacuum Microwave-Assisted Extraction Followed by Macroporous Resin Enrichment for the Separation of the Three Glycosides Salicin, Hyperin and Rutin from Populus Bark
Molecules 2014, 19(7), 9689-9711; https://doi.org/10.3390/molecules19079689
Received: 16 May 2014 / Revised: 23 June 2014 / Accepted: 1 July 2014 / Published: 7 July 2014
Cited by 16 | PDF Full-text (2136 KB) | HTML Full-text | XML Full-text
Abstract
An effective ionic liquid vacuum microwave-assisted method was developed for extraction of the thermo- and oxygen-sensitive glycosides salicin, hyperin and rutin from Populus bark due to the strong solvating effects of ionic liquids on plant cell walls. In this study, [C4mim]BF
[...] Read more.
An effective ionic liquid vacuum microwave-assisted method was developed for extraction of the thermo- and oxygen-sensitive glycosides salicin, hyperin and rutin from Populus bark due to the strong solvating effects of ionic liquids on plant cell walls. In this study, [C4mim]BF4 solution was selected as the extracting solution for extraction of the target analytes. After optimization by single factor experiments and response surface methodology, the optimum condition parameters were achieved, which included 1.0 M [C4mim]BF4, 2 h soaking time, −0.08 MPa vacuum, 20 min microwave irradiation time, 400 W microwave irradiation power and 25 mL/g liquid/solid ratio. Under the optimum conditions, higher extraction yields of salicin (35.53 mg/g), hyperin (1.32 mg/g) and rutin (2.40 mg/g) were obtained. Compared with other extraction methods, the developed method provided higher yields of the three target components after a relatively shorter extraction time (20 min). No obvious degradation of the target analytes was observed under the optimum conditions in performed stability studies and the proposed method had a high reproducibility. Meanwhile, after adsorption and desorption on macroporous D101 resin, the target analytes can be effectively separated from the [C4mim]BF4 ionic liquid extraction solution and the yields of salicin, hyperin and rutin were 89%, 82% and 84%, respectively. The recovered [C4mim]BF4 ionic liquid presented a good extraction effect on the three analytes after recycling five times. Full article
(This article belongs to the Section Natural Products Chemistry)
Figures

Figure 1

Open AccessArticle Synthesis and Photophysical Properties of the 2-(3-(2-Alkyl-6,8-diaryl-4-oxo-1,2,3,4-tetrahydroquinazolin-2-yl)propyl)-6,8-diarylquinazolin-4(3H)-ones
Molecules 2014, 19(7), 9712-9735; https://doi.org/10.3390/molecules19079712
Received: 6 June 2014 / Revised: 30 June 2014 / Accepted: 1 July 2014 / Published: 8 July 2014
Cited by 3 | PDF Full-text (1587 KB) | HTML Full-text | XML Full-text
Abstract
Iodine-catalyzed condensation of 2-amino-3,5-dibromobenzamide with cyclohexane-1,3-dione derivatives in refluxing toluene afforded the corresponding bisquinazolinones. Suzuki-Miyaura cross-coupling of the latter with arylboronic acids afforded tetraarylbisquinazolinones. The electronic absorption and emission properties of these tetraarylbisquinazolinones were measured in dimethylsulfoxide (DMSO) and acetic acid by means
[...] Read more.
Iodine-catalyzed condensation of 2-amino-3,5-dibromobenzamide with cyclohexane-1,3-dione derivatives in refluxing toluene afforded the corresponding bisquinazolinones. Suzuki-Miyaura cross-coupling of the latter with arylboronic acids afforded tetraarylbisquinazolinones. The electronic absorption and emission properties of these tetraarylbisquinazolinones were measured in dimethylsulfoxide (DMSO) and acetic acid by means of UV-Vis and fluorescence spectroscopic techniques in conjunction with quantum chemical methods to understand the influence of substituents on intramolecular charge transfer (ICT). Full article
(This article belongs to the Section Organic Chemistry)
Figures

Graphical abstract

Open AccessArticle Synthesis of Riboflavines, Quinoxalinones and Benzodiazepines through Chemoselective Flow Based Hydrogenations
Molecules 2014, 19(7), 9736-9759; https://doi.org/10.3390/molecules19079736
Received: 4 June 2014 / Revised: 25 June 2014 / Accepted: 2 July 2014 / Published: 8 July 2014
Cited by 15 | PDF Full-text (708 KB) | HTML Full-text | XML Full-text
Abstract
Robust chemical routes towards valuable bioactive entities such as riboflavines, quinoxalinones and benzodiazepines are described. These make use of modern flow hydrogenation protocols enabling the chemoselective reduction of nitro group containing building blocks in order to rapidly generate the desired amine intermediates in
[...] Read more.
Robust chemical routes towards valuable bioactive entities such as riboflavines, quinoxalinones and benzodiazepines are described. These make use of modern flow hydrogenation protocols enabling the chemoselective reduction of nitro group containing building blocks in order to rapidly generate the desired amine intermediates in situ. In order to exploit the benefits of continuous processing the individual steps were transformed into a telescoped flow process delivering selected benzodiazepine products on scales of 50 mmol and 120 mmol respectively. Full article
(This article belongs to the Special Issue Heterocycles in Supramolecular Chemistry)
Figures

Graphical abstract

Open AccessArticle A Novel Fungal Metabolite with Beneficial Properties for Agricultural Applications
Molecules 2014, 19(7), 9760-9772; https://doi.org/10.3390/molecules19079760
Received: 5 March 2014 / Revised: 26 June 2014 / Accepted: 1 July 2014 / Published: 8 July 2014
Cited by 18 | PDF Full-text (1020 KB) | HTML Full-text | XML Full-text
Abstract
Trichoderma are ubiquitous soil fungi that include species widely used as biocontrol agents in agriculture. Many isolates are known to secrete several secondary metabolites with different biological activities towards plants and other microbes. Harzianic acid (HA) is a T. harzianum metabolite able to
[...] Read more.
Trichoderma are ubiquitous soil fungi that include species widely used as biocontrol agents in agriculture. Many isolates are known to secrete several secondary metabolites with different biological activities towards plants and other microbes. Harzianic acid (HA) is a T. harzianum metabolite able to promote plant growth and strongly bind iron. In this work, we isolated from the culture filtrate of a T. harzianum strain a new metabolite, named isoharzianic acid (iso-HA), a stereoisomer of HA. The structure and absolute configuration of this compound has been determined by spectroscopic methods, including UV-Vis, MS, 1D and 2D NMR analyses. In vitro applications of iso-HA inhibited the mycelium radial growth of Sclerotinia sclerotiorum and Rhizoctonia solani. Moreover, iso HA improved the germination of tomato seeds and induced disease resistance. HPLC-DAD experiments showed that the production of HA and iso HA was affected by the presence of plant tissue in the liquid medium. In particular, tomato tissue elicited the production of HA but negatively modulated the biosynthesis of its analogue iso-HA, suggesting that different forms of the same Trichoderma secondary metabolite have specific roles in the molecular mechanism regulating the Trichoderma plant interaction. Full article
(This article belongs to the Section Metabolites)
Figures

Figure 1

Open AccessArticle Vasorelaxation Induced by a New Naphthoquinone-Oxime is Mediated by NO-sGC-cGMP Pathway
Molecules 2014, 19(7), 9773-9785; https://doi.org/10.3390/molecules19079773
Received: 19 May 2014 / Revised: 21 June 2014 / Accepted: 23 June 2014 / Published: 8 July 2014
Cited by 6 | PDF Full-text (408 KB) | HTML Full-text | XML Full-text
Abstract
It has been established that oximes cause endothelium-independent relaxation in blood vessels. In the present study, the cardiovascular effects of the new oxime 3-hydroxy-4–(hydroxyimino)-2-(3-methylbut-2-enylnaphtalen-1(4H)-one (Oxime S1) derived from lapachol were evaluated. In normotensive rats, administration of Oxime S1 (10,
[...] Read more.
It has been established that oximes cause endothelium-independent relaxation in blood vessels. In the present study, the cardiovascular effects of the new oxime 3-hydroxy-4–(hydroxyimino)-2-(3-methylbut-2-enylnaphtalen-1(4H)-one (Oxime S1) derived from lapachol were evaluated. In normotensive rats, administration of Oxime S1 (10, 15, 20 and 30 mg/Kg, i.v.) produced dose-dependent reduction in blood pressure. In isolated aorta and superior mesenteric artery rings, Oxime S1 induced endothelium-independent and concentration-dependent relaxations (10−8 M to 10−4 M). In addition, Oxime S1-induced vasorelaxations were attenuated by hydroxocobalamin or methylene blue in aorta and by PTIO or ODQ in mesenteric artery rings, suggesting a role for the nitric oxide (NO) pathway. Additionally, Oxime S1 (30 and 100 µM) significantly increased NO concentrations (13.9 ± 1.6 nM and 17.9 ± 4.1 nM, respectively) measured by nitric oxide microsensors. Furthermore, pre-contraction with KCl (80 mM) prevented Oxime S1-derived vasorelaxation in endothelium-denuded aortic rings. Of note, combined treatment with potassium channel inhibitors also reduced Oxime S1-mediated vasorelaxation suggesting a role for potassium channels, more precisely Kir, Kv and KATP channels. We observed the involvement of BKCa channels in Oxime S1-induced relaxation in mesenteric artery rings. In conclusion, these data suggest that the Oxime S1 induces hypotension and vasorelaxation via NO pathway by activating soluble guanylate cyclase (sGC) and K+ channels. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Figure 1

Open AccessArticle Isolation, Structural Analyses and Biological Activity Assays against Chronic Lymphocytic Leukemia of Two Novel Cytochalasins — Sclerotionigrin A and B
Molecules 2014, 19(7), 9786-9797; https://doi.org/10.3390/molecules19079786
Received: 21 March 2014 / Revised: 24 June 2014 / Accepted: 2 July 2014 / Published: 8 July 2014
Cited by 4 | PDF Full-text (281 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Two new cytochalasins, sclerotionigrin A (1) and B (2) were isolated together with the known proxiphomin (3) from the filamentous fungus Aspergillus sclerotioniger. The structures and relative stereochemistry of 1 and 2 were determined based on
[...] Read more.
Two new cytochalasins, sclerotionigrin A (1) and B (2) were isolated together with the known proxiphomin (3) from the filamentous fungus Aspergillus sclerotioniger. The structures and relative stereochemistry of 1 and 2 were determined based on comparison with 3, and from extensive 1D and 2D NMR spectroscopic analysis, supported by high resolution mass spectrometry (HRMS). Compounds 2 and 3 displayed cytotoxic activity towards chronic lymphocytic leukemia cells in vitro, with 3 being the most active. Full article
(This article belongs to the Special Issue Bioassay-Guided Isolation of Natural Products)
Figures

Graphical abstract

Open AccessArticle The Hydractinia echinata Test-System. III: Structure-Toxicity Relationship Study of Some Azo-, Azo-Anilide, and Diazonium Salt Derivatives
Molecules 2014, 19(7), 9798-9817; https://doi.org/10.3390/molecules19079798
Received: 17 April 2014 / Revised: 29 June 2014 / Accepted: 3 July 2014 / Published: 8 July 2014
Cited by 2 | PDF Full-text (205 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental
[...] Read more.
Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental results showed that the measured effectiveness Mlog(1/MRC50) does not depend on the number of azo groups or the ones corresponding to metobolites, but it is influenced by the number of anilide groups, as well as by the substituents’ positions within molecules. The conformational analysis pointed out the intramolecular hydrogen bonds, especially the simple tautomerization of quinoidic (STOH) or aminoidic (STNH2) type. The effectiveness is strongly influenced by the “push-pull” electronic effect, specific to two hydroxy or amino groups separated by an azo moiety (double alternate tautomery, (DAT), to the –COOH or –SO3H groups which are located in ortho or para position with respect to the azo group. The levels of the lipophylic/hydrophilic, electronic and steric equilibriums, pointed out by the Mlog(1/MRC50) values, enabled the calculation of their average values Clog(1/MRC50) (“Köln model”), characteristic to one derivative class (class isotoxicity). The azo group reduction and the hydrolysis of the amido/peptidic group are two concurrent enzymatic reactions, which occur with different reaction rates and mechanisms. The products of the partial biodegradation are aromatic amines. No additive or synergic effects are noticed among them. Full article
Open AccessArticle Additives Enhancing the Catalytic Properties of Lipase from Burkholderia cepacia Immobilized on Mixed-Function-Grafted Mesoporous Silica Gel
Molecules 2014, 19(7), 9818-9837; https://doi.org/10.3390/molecules19079818
Received: 16 May 2014 / Revised: 23 June 2014 / Accepted: 2 July 2014 / Published: 8 July 2014
Cited by 19 | PDF Full-text (517 KB) | HTML Full-text | XML Full-text
Abstract
Effects of various additives on the lipase from Burkholderia cepacia (BcL) immobilized on mixed-function-grafted mesoporous silica gel support by hydrophobic adsorption and covalent attachment were investigated. Catalytic properties of the immobilized biocatalysts were characterized in kinetic resolution of racemic 1-phenylethanol (
[...] Read more.
Effects of various additives on the lipase from Burkholderia cepacia (BcL) immobilized on mixed-function-grafted mesoporous silica gel support by hydrophobic adsorption and covalent attachment were investigated. Catalytic properties of the immobilized biocatalysts were characterized in kinetic resolution of racemic 1-phenylethanol (rac-1a) and 1-(thiophen-2-yl)ethan-1-ol (rac-1b). Screening of more than 40 additives showed significantly enhanced productivity of immobilized BcL with several additives such as PEGs, oleic acid and polyvinyl alcohol. Effects of substrate concentration and temperature between 0–100 °C on kinetic resolution of rac-1a were studied with the best adsorbed BcLs containing PEG 20 k or PVA 18–88 additives in continuous-flow packed-bed reactor. The optimum temperature of lipase activity for BcL co-immobilized with PEG 20k found at around 30 °C determined in the continuous-flow system increased remarkably to around 80 °C for BcL co-immobilized with PVA 18–88. Full article
(This article belongs to the Special Issue Enzyme Immobilization)
Figures

Graphical abstract

Open AccessArticle Glutaraldehyde Cross-Linking of Immobilized Thermophilic Esterase on Hydrophobic Macroporous Resin for Application in Poly(ε-caprolactone) Synthesis
Molecules 2014, 19(7), 9838-9849; https://doi.org/10.3390/molecules19079838
Received: 21 May 2014 / Revised: 3 July 2014 / Accepted: 4 July 2014 / Published: 8 July 2014
Cited by 9 | PDF Full-text (330 KB) | HTML Full-text | XML Full-text
Abstract
The immobilized thermophilic esterase from Archaeoglobus fulgidus was successfully constructed through the glutaraldehyde-mediated covalent coupling after its physical adsorption on a hydrophobic macroporous resin, Sepabeads EC-OD. Through 0.05% glutaraldehyde treatment, the prevention of enzyme leaching and the maintenance of catalytic activity could be
[...] Read more.
The immobilized thermophilic esterase from Archaeoglobus fulgidus was successfully constructed through the glutaraldehyde-mediated covalent coupling after its physical adsorption on a hydrophobic macroporous resin, Sepabeads EC-OD. Through 0.05% glutaraldehyde treatment, the prevention of enzyme leaching and the maintenance of catalytic activity could be simultaneously realized. Using the enzymatic ring-opening polymerization of ε-caprolactone as a model, effects of organic solvents and reaction temperature on the monomer conversion and product molecular weight were systematically investigated. After the optimization of reaction conditions, products were obtained with 100% monomer conversion and Mn values lower than 1010 g/mol. Furthermore, the cross‑linked immobilized thermophilic esterase exhibited an excellent operational stability, with monomer conversion values exceeding 90% over the course of 12 batch reactions, still more than 80% after 16 batch reactions. Full article
(This article belongs to the Special Issue Enzyme Immobilization)
Figures

Figure 1

Open AccessArticle Preparation of Polyphosphazene Hydrogels for Enzyme Immobilization
Molecules 2014, 19(7), 9850-9863; https://doi.org/10.3390/molecules19079850
Received: 19 May 2014 / Revised: 23 June 2014 / Accepted: 24 June 2014 / Published: 8 July 2014
Cited by 8 | PDF Full-text (490 KB) | HTML Full-text | XML Full-text
Abstract
We report on the synthesis and application of a new hydrogel based on a methacrylate substituted polyphosphazene. Through ring-opening polymerization and nucleophilic substitution, poly[bis(methacrylate)phosphazene] (PBMAP) was successfully synthesized from hexachlorocyclotriphosphazene. By adding PBMAP to methacrylic acid solution and then treating with UV light,
[...] Read more.
We report on the synthesis and application of a new hydrogel based on a methacrylate substituted polyphosphazene. Through ring-opening polymerization and nucleophilic substitution, poly[bis(methacrylate)phosphazene] (PBMAP) was successfully synthesized from hexachlorocyclotriphosphazene. By adding PBMAP to methacrylic acid solution and then treating with UV light, we could obtain a cross-linked polyphosphazene network, which showed an ultra-high absorbency for distilled water. Lipase from Candida rugosa was used as the model lipase for entrapment immobilization in the hydrogel. The influence of methacrylic acid concentration on immobilization efficiency was studied. Results showed that enzyme loading reached a maximum of 24.02 mg/g with an activity retention of 67.25% when the methacrylic acid concentration was 20% (w/w). Full article
(This article belongs to the Special Issue Enzyme Immobilization)
Figures

Figure 1

Open AccessArticle T-Type Ca2+ Channel Blocker, KYS05090 Induces Autophagy and Apoptosis in A549 Cells through Inhibiting Glucose Uptake
Molecules 2014, 19(7), 9864-9875; https://doi.org/10.3390/molecules19079864
Received: 27 May 2014 / Revised: 27 June 2014 / Accepted: 3 July 2014 / Published: 8 July 2014
Cited by 10 | PDF Full-text (384 KB) | HTML Full-text | XML Full-text
Abstract
It has been reported that [3-(1,1'-biphenyl-4-yl)-2-(1-methyl-5-dimethylamino-pentylamino)-3,4-dihydroquinazolin-4-yl]-N-benzylacetamide 2hydrochloride (KYS05090), a selective T-type Ca2+ channel blocker, reduces tumor volume and weight in the A549 xenograft model, but the molecular mechanism of cell death has not yet been elucidated. In this study, KYS05090
[...] Read more.
It has been reported that [3-(1,1'-biphenyl-4-yl)-2-(1-methyl-5-dimethylamino-pentylamino)-3,4-dihydroquinazolin-4-yl]-N-benzylacetamide 2hydrochloride (KYS05090), a selective T-type Ca2+ channel blocker, reduces tumor volume and weight in the A549 xenograft model, but the molecular mechanism of cell death has not yet been elucidated. In this study, KYS05090 induced autophagy- and apoptosis-mediated cell death in human lung adenocarcinoma A549 cells. Although KYS05090 decreased intracellular Ca2+ levels, it was not directly related with KYS05090-induced cell death. In addition, KYS05090 generated intracellular reactive oxygen species (ROS) and reduced glucose uptake, and catalase and methyl pyruvate prevented KYS05090-induced cell death. These results indicate that KYS05090 can lead to autophagy and apoptosis in A549 cells through ROS generation by inhibiting glucose uptake. Our findings suggest that KYS05090 has potential chemotherapeutic value for the treatment of lung cancer. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Graphical abstract

Open AccessArticle Fluorescent Lectins for Local in Vivo Visualization of Peripheral Nerves
Molecules 2014, 19(7), 9876-9892; https://doi.org/10.3390/molecules19079876
Received: 7 May 2014 / Revised: 19 June 2014 / Accepted: 1 July 2014 / Published: 8 July 2014
Cited by 2 | PDF Full-text (1944 KB) | HTML Full-text | XML Full-text
Abstract
Damage to peripheral nerves caused during a surgical intervention often results in function loss. Fluorescence imaging has the potential to improve intraoperative identification and preservation of these structures. However, only very few nerve targeting agents are available. This study describes the in vivo
[...] Read more.
Damage to peripheral nerves caused during a surgical intervention often results in function loss. Fluorescence imaging has the potential to improve intraoperative identification and preservation of these structures. However, only very few nerve targeting agents are available. This study describes the in vivo nerve staining capabilities of locally administered fluorescent lectin-analogues. To this end WGA, PNA, PHA-L and LEL were functionalized with Cy5 (λex max 640 nm; λem max 680 nm). Transfer of these imaging agents along the sciatic nerve was evaluated in Thy1-YFP mice (n = 12) after intramuscular injection. Migration from the injection site was assessed in vivo using a laboratory fluorescence scanner and ex vivo via fluorescence confocal microscopy. All four lectins showed retrograde movement and staining of the epineurium with a signal-to-muscle ratio of around two. On average, the longest transfer distance was obtained with WGA-Cy5 (0.95 cm). Since WGA also gave minimal uptake in the lymphatic system, this lectin type revealed the highest potential as a migration imaging agent to visualize nerves. Full article
(This article belongs to the Special Issue Fluorescent Probes)
Figures

Figure 1

Open AccessArticle Homoconjugation vs. Exciton Coupling in Chiral α,β-Unsaturated Bicyclo[3.3.1]nonane Dinitrile and Carboxylic Acids
Molecules 2014, 19(7), 9893-9906; https://doi.org/10.3390/molecules19079893
Received: 4 May 2014 / Revised: 3 June 2014 / Accepted: 5 June 2014 / Published: 8 July 2014
Cited by 2 | PDF Full-text (606 KB) | HTML Full-text | XML Full-text
Abstract
The chiroptical properties of enantiomerically pure bicyclo[3.3.1]nona-2,6-diene-2,6-dicarbonitrile and related acids were studied by circular dichroism spectroscopy and theoretical computations. A consideration of the molecular structure of the synthesized difunctional compounds revealed that chromophores are predisposed to transannular through-space interaction due to a favourable
[...] Read more.
The chiroptical properties of enantiomerically pure bicyclo[3.3.1]nona-2,6-diene-2,6-dicarbonitrile and related acids were studied by circular dichroism spectroscopy and theoretical computations. A consideration of the molecular structure of the synthesized difunctional compounds revealed that chromophores are predisposed to transannular through-space interaction due to a favourable conformation of the bicyclic skeleton and a rather small interchromophoric distance. Evidence for non-exciton-type coupling between the two acrylonitrile and acrylate moieties in 3 and 4, respectively, was obtained by chiroptical spectroscopy and DFT calculations. Full article
(This article belongs to the Special Issue Dynamic Stereochemistry)
Figures

Figure 1

Open AccessArticle Stability of Sunscreens Containing CePO4: Proposal for a New Inorganic UV Filter
Molecules 2014, 19(7), 9907-9925; https://doi.org/10.3390/molecules19079907
Received: 1 May 2014 / Revised: 30 June 2014 / Accepted: 1 July 2014 / Published: 9 July 2014
Cited by 4 | PDF Full-text (932 KB) | HTML Full-text | XML Full-text
Abstract
Inorganic UV filters have become attractive because of their role in protecting the skin from the damage caused by continuous exposure to the sun. However, their large refractive index and high photocatalytic activity have led to the development of alternative inorganic materials such
[...] Read more.
Inorganic UV filters have become attractive because of their role in protecting the skin from the damage caused by continuous exposure to the sun. However, their large refractive index and high photocatalytic activity have led to the development of alternative inorganic materials such as CePO4 for application as UV filters. This compound leaves a low amount of white residue on the skin and is highly stable. The aim of this study was to evaluate the physical and chemical stability of a cosmetic formulation containing ordinary organic UV filters combined with 5% CePO4, and, to compare it with other formulations containing the same vehicle with 5% TiO2 or ZnO as inorganic materials. The rheological behavior and chemical stability of the formulations containing these different UV filters were investigated. Results showed that the formulation containing CePO4 is a promising innovative UV filter due to its low interaction with organic filters, which culminates in longer shelf life when compared with traditional formulations containing ZnO or TiO2 filters. Moreover, the recognized ability of CePO4 to leave a low amount of white residue on the skin combined with great stability, suggests that CePO4 can be used as inorganic filter in high concentrations, affording formulations with high SPF values. Full article
Figures

Figure 1

Open AccessArticle 1,4-Disubstituted Thiosemicarbazide Derivatives are Potent Inhibitors of Toxoplasma gondii Proliferation
Molecules 2014, 19(7), 9926-9943; https://doi.org/10.3390/molecules19079926
Received: 11 June 2014 / Revised: 27 June 2014 / Accepted: 27 June 2014 / Published: 9 July 2014
Cited by 14 | PDF Full-text (605 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A series of 4-arylthiosemicarbazides substituted at the N1 position with a 5-membered heteroaryl ring was synthesized and evaluated in vitro for T. gondii inhibition proliferation and host cell cytotoxicity. At non-toxic concentrations for the host cells all studied compounds displayed excellent
[...] Read more.
A series of 4-arylthiosemicarbazides substituted at the N1 position with a 5-membered heteroaryl ring was synthesized and evaluated in vitro for T. gondii inhibition proliferation and host cell cytotoxicity. At non-toxic concentrations for the host cells all studied compounds displayed excellent anti-parasitic effects when compared to sulfadiazine, indicating a high selectivity of their anti-T. gondii activity. The differences in bioactivity investigated by DFT calculations suggest that the inhibitory activity of 4-aryl-thiosemicarbazides towards T. gondii proliferation is connected with the electronic structure of the molecule. Further, these compounds were tested as potential antibacterial agents. No growth-inhibiting effect on any of the test microorganisms was observed for all the compounds, even at high concentrations. Full article
(This article belongs to the Section Medicinal Chemistry)
Figures

Graphical abstract

Open AccessArticle Relative Quantitation of Glycopeptides Based on Stable Isotope Labeling Using MALDI-TOF MS
Molecules 2014, 19(7), 9944-9961; https://doi.org/10.3390/molecules19079944
Received: 31 March 2014 / Revised: 1 July 2014 / Accepted: 7 July 2014 / Published: 9 July 2014
Cited by 7 | PDF Full-text (572 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We have developed an effective, sensitive method for quantitative glycopeptide profiling using stable isotope labeling and MALDI-TOF mass spectrometry (MS). In this study, we synthesized benzoic acid-d0 N-succinimidyl ester (BzOSu) and benzoic acid-d5 N-succinimidyl ester (d-BzOSu) as light and heavy isotope reagents for
[...] Read more.
We have developed an effective, sensitive method for quantitative glycopeptide profiling using stable isotope labeling and MALDI-TOF mass spectrometry (MS). In this study, we synthesized benzoic acid-d0 N-succinimidyl ester (BzOSu) and benzoic acid-d5 N-succinimidyl ester (d-BzOSu) as light and heavy isotope reagents for stable isotope quantification for the comparative analysis of glycopeptides. Using this approach provided enhanced ionization efficiency in both positive and negative modes by MALDI-TOF MS. These reagents were quantitatively reacted with glycopeptides from human serum IgG (hIgG) at a wide range of concentrations; the labeling efficiency of the glycopeptides showed high reproducibility and a good calibration curve was obtained. To demonstrate the practical utility of this approach, we characterized the structures of glycopeptides from hIgG and from IgG1 produced by myeloma plasma. The glycopeptides were quantitatively analyzed by mixing Bz-labeled IgG1 glycopeptides with d-Bz-labeled hIgG glycopeptides. Glycan structural identification of the hIgG glycopeptides was demonstrated by combining the highly specific recognition of endo-β-N-acetyl glucosaminidases from Streptococcus pyogenes (endoS) or from Streptococcus pneumoniae (endo-D) with MALDI-TOF MS analysis. The obtained data revealed the glycan profile and the ratio of glycan structural isomers containing a galactosylated extension on IgG1, IgG2 and IgG3 glycopetides. Full article
(This article belongs to the Special Issue Oligosaccharides and Glyco-Conjugates)
Figures

Graphical abstract

Open AccessArticle A Comparative Study on the Electrochemical Corrosion Behavior of Iron and X-65 Steel in 4.0 wt % Sodium Chloride Solution after Different Exposure Intervals
Molecules 2014, 19(7), 9962-9974; https://doi.org/10.3390/molecules19079962
Received: 13 May 2014 / Revised: 30 June 2014 / Accepted: 3 July 2014 / Published: 9 July 2014
Cited by 18 | PDF Full-text (295 KB) | HTML Full-text | XML Full-text
Abstract
In this work, the results obtained from studying the anodic dissolution of pure iron and API X-65 5L pipeline steel after 40 min and 12 h exposure period in 4.0 wt % NaCl solutions at room temperature were reported. Potential-time, electrochemical impedance spectroscopy,
[...] Read more.
In this work, the results obtained from studying the anodic dissolution of pure iron and API X-65 5L pipeline steel after 40 min and 12 h exposure period in 4.0 wt % NaCl solutions at room temperature were reported. Potential-time, electrochemical impedance spectroscopy, potentiodynamic polarization, and chronoamperometric current-time at constant potential techniques were employed. It has been found that the iron electrode corrodes in the chloride test solutions faster than the API X-65 5L steel does under the same conditions. Increasing the exposure period for the electrodes from 40 min to 12 h showed a significant reduction in the corrosion parameters for both iron and steel in the 4.0 wt % NaCl solution. Results together confirmed clearly that the X-65 steel is superior to iron against corrosion in sodium chloride solutions. Full article
Figures

Graphical abstract

Open AccessArticle Susceptibility of Opportunistic Burkholderia glumae to Copper Surfaces Following Wet or Dry Surface Contact
Molecules 2014, 19(7), 9975-9985; https://doi.org/10.3390/molecules19079975
Received: 21 March 2014 / Revised: 3 July 2014 / Accepted: 4 July 2014 / Published: 9 July 2014
Cited by 6 | PDF Full-text (929 KB) | HTML Full-text | XML Full-text
Abstract
Burkholderia glumae has been proposed to have a potential risk to vulnerable communities. In this work, we investigated the antibacterial activity and mechanism of copper surfaces against multi-drug resistant B. glumae from both patients and rice plants. The susceptibility of B
[...] Read more.
Burkholderia glumae has been proposed to have a potential risk to vulnerable communities. In this work, we investigated the antibacterial activity and mechanism of copper surfaces against multi-drug resistant B. glumae from both patients and rice plants. The susceptibility of B. glumae to copper surfaces was noted by a significant decline in viable bacterial counts, relative to the slight reduction of stainless steel and polyvinylchloride, both of which were used as control surfaces. The mode of action of bacterial killing was determined by examing the mutagenicity, DNA damage, copper ions accumulation, and membrane damage in bacterial cells. The results indicated that the cells exposed to copper surfaces did not cause severe DNA lesions or increase the mutation frequencies, but resulted in a loss of cell membrane integrity within minutes. Furthermore, bacterial cells exposed to copper surfaces accumulated significantly higher amounts of copper compared to control surfaces. Overall, this study showed that metallic copper had strong antibacterial effect against B. glumae by causing DNA and membrane damage, cellular accumulation of copper, and cell death following DNA degradation, which could be utilized to reduce the risk of bacterial contamination and infection. Full article
(This article belongs to the Special Issue Practical Applications of Metal Complexes)
Figures

Figure 1

Open AccessArticle Batch and Continuous Flow Preparation of Hantzsch 1,4-Dihydropyridines under Microwave Heating and Simultaneous Real-time Monitoring by Raman Spectroscopy. An Exploratory Study
Molecules 2014, 19(7), 9986-9998; https://doi.org/10.3390/molecules19079986
Received: 23 May 2014 / Revised: 19 June 2014 / Accepted: 26 June 2014 / Published: 9 July 2014
Cited by 7 | PDF Full-text (2294 KB) | HTML Full-text | XML Full-text
Abstract
Dialkyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylates have been prepared in a batch mode under conventional heating as well as under continuous flow conditions in the Miniflow 200SS, Sairem’s microwave-assisted batch and continuous flow equipment. Real-time monitoring of the reactions by Raman spectroscopy enabled to compare both heating
[...] Read more.
Dialkyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylates have been prepared in a batch mode under conventional heating as well as under continuous flow conditions in the Miniflow 200SS, Sairem’s microwave-assisted batch and continuous flow equipment. Real-time monitoring of the reactions by Raman spectroscopy enabled to compare both heating modes and to determine (optimized) reaction times. Full article
(This article belongs to the Special Issue ECSOC-17)
Figures

Graphical abstract

Open AccessArticle Lycodine-Type Alkaloids from Lycopodiastrum casuarinoides and Their Acetylcholinesterase Inhibitory Activity
Molecules 2014, 19(7), 9999-10010; https://doi.org/10.3390/molecules19079999
Received: 23 May 2014 / Revised: 18 June 2014 / Accepted: 27 June 2014 / Published: 10 July 2014
Cited by 7 | PDF Full-text (379 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Four new lycodine-type alkaloids, namely 16-hydroxyhuperzine B (1), N-methyl-11-acetoxyhuperzine B (2), 8,15-dihydrolycoparin A (3) and (7S,12S,13R)-huperzine D-16-O-β-d-glucopyranoside (4), along with ten known analogues 514
[...] Read more.
Four new lycodine-type alkaloids, namely 16-hydroxyhuperzine B (1), N-methyl-11-acetoxyhuperzine B (2), 8,15-dihydrolycoparin A (3) and (7S,12S,13R)-huperzine D-16-O-β-d-glucopyranoside (4), along with ten known analogues 514, were isolated from the whole plant of Lycopodiastrum casuarinoides. The structures of the new compounds were elucidated by means of spectroscopic techniques (IR, MS, NMR, and CD) and chemical methods. Compounds 1 and 2 possessed four connected six-membered rings, while compounds 3 and 4 were piperidine ring cleavage products. In particular, compound 4 was a lycopodium alkaloidal glycoside which is reported for the first time. Among the isolated compounds N-demethylhuperzinine (7), huperzine C (8), huperzine B (9) and lycoparin C (13) possessed significant inhibitory activity against acetylcholinesterase, and the new compound 1 showed moderate inhibitory activity. The structure activity relationships were discussed. Full article
(This article belongs to the Special Issue Alkaloids: Novel Therapeutic Perspectives)
Figures

Figure 1

Open AccessArticle Plumbagin Modulates Leukemia Cell Redox Status
Molecules 2014, 19(7), 10011-10032; https://doi.org/10.3390/molecules190710011
Received: 3 June 2014 / Revised: 20 June 2014 / Accepted: 25 June 2014 / Published: 10 July 2014
Cited by 12 | PDF Full-text (1235 KB) | HTML Full-text | XML Full-text
Abstract
Plumbagin is a plant naphtoquinone exerting anti-cancer properties including apoptotic cell death induction and generation of reactive oxygen species (ROS). The aim of this study was to elucidate parameters explaining the differential leukemia cell sensitivity towards this compound. Among several leukemia cell lines,
[...] Read more.
Plumbagin is a plant naphtoquinone exerting anti-cancer properties including apoptotic cell death induction and generation of reactive oxygen species (ROS). The aim of this study was to elucidate parameters explaining the differential leukemia cell sensitivity towards this compound. Among several leukemia cell lines, U937 monocytic leukemia cells appeared more sensitive to plumbagin treatment in terms of cytotoxicity and level of apoptotic cell death compared to more resistant Raji Burkitt lymphoma cells. Moreover, U937 cells exhibited a ten-fold higher ROS production compared to Raji. Neither differential incorporation, nor efflux of plumbagin was detected. Pre-treatment with thiol-containing antioxidants prevented ROS production and subsequent induction of cell death by apoptosis whereas non-thiol-containing antioxidants remained ineffective in both cellular models. We conclude that the anticancer potential of plumbagin is driven by pro-oxidant activities related to the cellular thiolstat. Full article
Figures

Graphical abstract