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Molecules, Volume 22, Issue 11 (November 2017)

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Cover Story (view full-size image) The strained dispiro hydrocarbon was endowed with high electron donating ability, which undergo [...] Read more.
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Open AccessArticle Solid Lipid Nanoparticles of Albendazole for Enhancing Cellular Uptake and Cytotoxicity against U-87 MG Glioma Cell Lines
Molecules 2017, 22(11), 2040; https://doi.org/10.3390/molecules22112040
Received: 27 October 2017 / Revised: 14 November 2017 / Accepted: 21 November 2017 / Published: 22 November 2017
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Abstract
Albendazole (ABZ) is an antihelminthic drug used for the treatment of several parasitic infestations. In addition to this, there are reports on the anticancer activity of ABZ against a wide range of cancer types. However, its effect on glioma has not yet been
[...] Read more.
Albendazole (ABZ) is an antihelminthic drug used for the treatment of several parasitic infestations. In addition to this, there are reports on the anticancer activity of ABZ against a wide range of cancer types. However, its effect on glioma has not yet been reported. In the present study, cytotoxicity of ABZ and ABZ loaded solid lipid nanoparticles (ASLNs) was tested in human glioma/astrocytoma cell line (U-87 MG). Using glyceryl trimyristate as lipid carrier and tween 80 as surfactant spherical ASLNs with an average size of 218.4 ± 5.1 nm were prepared by a combination of high shear homogenization and probe sonication methods. A biphasic in vitro release pattern of ABZ from ASLNs was observed, where 82% of ABZ was released in 24 h. In vitro cell line studies have shown that ABZ in the form of ASLNs was more cytotoxic (IC50 = 4.90 µg/mL) to U-87 MG cells compared to ABZ in the free form (IC50 = 13.30 µg/mL) due to the efficient uptake of the former by these cells. Full article
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Open AccessArticle Direct Modification of Microcrystalline Cellulose with Ethylenediamine for Use as Adsorbent for Removal Amitriptyline Drug from Environment
Molecules 2017, 22(11), 2039; https://doi.org/10.3390/molecules22112039
Received: 4 October 2017 / Revised: 2 November 2017 / Accepted: 17 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (4556 KB) | HTML Full-text | XML Full-text
Abstract
Cellulose derivatives have been widely used as adsorbents for the removal of micropollutants such as drugs, dyes, and metals, due to their abundance, low cost and non-contaminating nature. In this context, several studies have been performed searching for new adsorbents (cellulose derivatives) efficient
[...] Read more.
Cellulose derivatives have been widely used as adsorbents for the removal of micropollutants such as drugs, dyes, and metals, due to their abundance, low cost and non-contaminating nature. In this context, several studies have been performed searching for new adsorbents (cellulose derivatives) efficient at contaminant removal from aqueous solutions. Thus, a new adsorbent was synthesized by chemical modification of cellulose with ethylenediamine in the absence of solvent and applied to the adsorption of amitriptyline (AMI) in aqueous solution. The modification reaction was confirmed by X-ray Diffraction (XRD), elemental analysis, Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry/Differential Scanning Calorimeter (TG/DSC), solid state Nuclear Magnetic Resonance of 1H and 13C (1H-NMR and 13C-NMR). Moreover, the effectiveness of reaction was confirmed by computational calculations using Density Functional Theory (DFT) at level B3LYP/6-31G(d). This adsorption process was influenced by pH, time, concentration, temperature and did not show significant changes due to the ionic strength variation. Through these experiments, it was observed that the maximum adsorption capacity of AMI by CN polymer at 298 K, 300 min, and pH 7 was 87.66 ± 0.60 mg·g−1. Full article
(This article belongs to the Special Issue Cellulose Chemical Modifications—Towards Sustainable Materials)
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Open AccessArticle Preparation of Vitexin Nanoparticles by Combining the Antisolvent Precipitation and High Pressure Homogenization Approaches Followed by Lyophilization for Dissolution Rate Enhancement
Molecules 2017, 22(11), 2038; https://doi.org/10.3390/molecules22112038
Received: 23 October 2017 / Revised: 16 November 2017 / Accepted: 18 November 2017 / Published: 22 November 2017
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Abstract
Vitexin, a natural flavonoid found in many medicinal plants, is well known for its rich pharmacological activities. However, the poor water solubility of vitexin has limited its therapeutic application. The aim of this study was to prepare the nanoparticles of vitexin by combining
[...] Read more.
Vitexin, a natural flavonoid found in many medicinal plants, is well known for its rich pharmacological activities. However, the poor water solubility of vitexin has limited its therapeutic application. The aim of this study was to prepare the nanoparticles of vitexin by combining the antisolvent precipitation (ASP) and high pressure homogenization (HPH) approaches followed by lyophilization for improving the dissolution rate of this poorly water-soluble drug. The effects of main factors influencing the mean particle size (MPS) of vitexin were investigated and optimized. Under optimum conditions, vitexin nanosuspensions with an MPS of 80.5 nm were obtained and then lyophilized to form nanoparticles. The obtained vitexin nanoparticles were further characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), mass spectrometry (MS), X-ray powder diffraction (XRPD), gas chromatography (GC) and dissolution testing. The results showed that the nanoparticles of vitexin were converted into an amorphous form, with its chemical structure unchanged. Additionally, the residual dimethyl sulfoxide (DMSO) is lower than the International Conference on Harmonization (ICH) limit for class 3 solvents. The dissolution rate of processed vitexin was significantly higher (5.58-fold) than that of raw drug. Overall, the combinative process we developed is an effective way to produce vitexin nanoparticles with markedly enhanced dissolution rate. Full article
(This article belongs to the Section Nanochemistry)
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Open AccessArticle Large-Scale Analysis of Antimicrobial Activities in Relation to Amphipathicity and Charge Reveals Novel Characterization of Antimicrobial Peptides
Molecules 2017, 22(11), 2037; https://doi.org/10.3390/molecules22112037
Received: 16 October 2017 / Revised: 13 November 2017 / Accepted: 20 November 2017 / Published: 22 November 2017
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Abstract
It has been unclear to which antimicrobial activities (e.g., anti-gram-positive bacterial, anti-gram-negative bacterial, antifungal, antiparasitic, and antiviral activities) of antimicrobial peptides (AMPs) a given physiochemical property matters most. This is the first computational study using large-scale AMPs to examine the relationships between antimicrobial
[...] Read more.
It has been unclear to which antimicrobial activities (e.g., anti-gram-positive bacterial, anti-gram-negative bacterial, antifungal, antiparasitic, and antiviral activities) of antimicrobial peptides (AMPs) a given physiochemical property matters most. This is the first computational study using large-scale AMPs to examine the relationships between antimicrobial activities and two major physiochemical properties of AMPs—amphipathicity and net charge. The results showed that among all kinds of antimicrobial activities, amphipathicity and net charge best differentiated between AMPs with and without anti-gram-negative bacterial activities. In terms of amphipathicity and charge, all the AMPs whose activities were significantly associated with amphipathicity and net charge were alike except those with anti-gram-positive bacterial activities. Furthermore, the higher the amphipathic value, the greater the proportion of AMPs possessing both antibacterial and antifungal activities. This dose–response-like pattern suggests a possible causal relationship—dual antibacterial and antifungal activities of AMPs may be attributable to amphipathicity. These novel findings could be useful for identifying potent AMPs computationally. Full article
(This article belongs to the Special Issue Bioactive Natural Peptides As A Pipeline For Therapeutics)
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Open AccessArticle Action of Monomeric/Gemini Surfactants on Free Cells and Biofilm of Asaia lannensis
Molecules 2017, 22(11), 2036; https://doi.org/10.3390/molecules22112036
Received: 25 October 2017 / Revised: 19 November 2017 / Accepted: 21 November 2017 / Published: 22 November 2017
Cited by 2 | PDF Full-text (1617 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
We investigated the biological activity of surfactants based on quaternary ammonium compounds: gemini surfactant hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide) (C6), synthesized by the reaction of N,N-dimethyl-N-dodecylamine with 1,6-dibromohexane, and its monomeric analogue dodecyltrimethylammonium bromide (DTAB). The experiments were performed
[...] Read more.
We investigated the biological activity of surfactants based on quaternary ammonium compounds: gemini surfactant hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide) (C6), synthesized by the reaction of N,N-dimethyl-N-dodecylamine with 1,6-dibromohexane, and its monomeric analogue dodecyltrimethylammonium bromide (DTAB). The experiments were performed with bacteria Asaia lannensis, a common spoilage in the beverage industry. The minimal inhibitory concentration (MIC) values were determined using the tube standard two-fold dilution method. The growth and adhesive properties of bacterial cells were studied in different culture media, and the cell viability was evaluated using plate count method. Both of the surfactants were effective against the bacterial strain, but the MIC of gemini compound was significantly lower. Both C6 and DTAB exhibited anti-adhesive abilities. Treatment with surfactants at or below MIC value decreased the number of bacterial cells that were able to form biofilm, however, the gemini surfactant was more effective. The used surfactants were also found to be able to eradicate mature biofilms. After 4 h of treatment with C6 surfactant at concentration 10 MIC, the number of bacterial cells was reduced by 91.8%. The results of this study suggest that the antibacterial activity of the gemini compound could make it an effective microbiocide against the spoilage bacteria Asaia sp. in both planktonic and biofilm stages. Full article
(This article belongs to the Section Chemical Biology)
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Open AccessArticle A New Synthetic Route to Polyhydrogenated Pyrrolo[3,4-b]pyrroles by the Domino Reaction of 3-Bromopyrrole-2,5-Diones with Aminocrotonic Acid Esters
Molecules 2017, 22(11), 2035; https://doi.org/10.3390/molecules22112035
Received: 4 November 2017 / Revised: 16 November 2017 / Accepted: 20 November 2017 / Published: 22 November 2017
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Abstract
A new synthetic approach to polyfunctional hexahydropyrrolo[3,4-b]pyrroles was developed based on cyclization of N-arylbromomaleimides with aminocrotonic acid esters. A highly chemo- and stereoselective reaction is a Hantzsch-type domino process, involving the steps of initial nucleophilic C-addition or substitution and subsequent intramolecular
[...] Read more.
A new synthetic approach to polyfunctional hexahydropyrrolo[3,4-b]pyrroles was developed based on cyclization of N-arylbromomaleimides with aminocrotonic acid esters. A highly chemo- and stereoselective reaction is a Hantzsch-type domino process, involving the steps of initial nucleophilic C-addition or substitution and subsequent intramolecular nucleophilic addition without recyclyzation of imide cycle. Full article
(This article belongs to the collection Heterocyclic Compounds)
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Open AccessArticle Multicenter (FX)n/NH3 Halogen Bonds (X = Cl, Br and n = 1–5). QTAIM Descriptors of the Strength of the X∙∙∙N Interaction
Molecules 2017, 22(11), 2034; https://doi.org/10.3390/molecules22112034
Received: 10 October 2017 / Revised: 14 November 2017 / Accepted: 14 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (1615 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In the present work an in depth deep electronic study of multicenter XBs (FX)n/NH3 (X = Cl, Br and n = 1–5) is conducted. The ways in which X∙∙∙X lateral contacts affect the electrostatic or covalent nature of the X∙∙∙N
[...] Read more.
In the present work an in depth deep electronic study of multicenter XBs (FX)n/NH3 (X = Cl, Br and n = 1–5) is conducted. The ways in which X∙∙∙X lateral contacts affect the electrostatic or covalent nature of the X∙∙∙N interactions are explored at the CCSD(T)/aug-cc-pVTZ level and in the framework of the quantum theory of atoms in molecules (QTAIM). Calculations show that relatively strong XBs have been found with interaction energies lying between −41 and −90 kJ mol−1 for chlorine complexes, and between −56 and −113 kJ mol−1 for bromine complexes. QTAIM parameters reveal that in these complexes: (i) local (kinetics and potential) energy densities measure the ability that the system has to concentrate electron charge density at the intermolecular X∙∙∙N region; (ii) the delocalization indices [δ(A,B)] and the exchange contribution [VEX(X,N)] of the interacting quantum atoms (IQA) scheme, could constitute a quantitative measure of the covalence of these molecular interactions; (iii) both classical electrostatic and quantum exchange show high values, indicating that strong ionic and covalent contributions are not mutually exclusive. Full article
(This article belongs to the Special Issue Halogen Bonds and Beyond)
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Open AccessArticle WxC-β-SiC Nanocomposite Catalysts Used in Aqueous Phase Hydrogenation of Furfural
Molecules 2017, 22(11), 2033; https://doi.org/10.3390/molecules22112033
Received: 5 October 2017 / Revised: 17 November 2017 / Accepted: 19 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (8430 KB) | HTML Full-text | XML Full-text
Abstract
This study investigates the effects of the addition of tungsten on the structure, phase composition, textural properties and activities of β-SiC-based catalysts in the aqueous phase hydrogenation of furfural. Carbothermal reduction of SiO2 in the presence of WO3 at 1550 °C
[...] Read more.
This study investigates the effects of the addition of tungsten on the structure, phase composition, textural properties and activities of β-SiC-based catalysts in the aqueous phase hydrogenation of furfural. Carbothermal reduction of SiO2 in the presence of WO3 at 1550 °C in argon resulted in the formation of WxC-β-SiC nanocomposite powders with significant variations in particle morphology and content of WxC-tipped β-SiC nano-whiskers, as revealed by TEM and SEM-EDS. The specific surface area (SSA) of the nanocomposite strongly depended on the amount of tungsten and had a notable impact on its catalytic properties for the production of furfuryl alcohol (FA) and tetrahydrofurfuryl alcohol (THFA). Nanocomposite WxC-β-SiC catalysts with 10 wt % W in the starting mixture had the highest SSA and the smallest WxC crystallites. Some 10 wt % W nanocomposite catalysts demonstrated up to 90% yield of THFA, in particular in the reduction of furfural derived from biomass, although the reproducible performance of such catalysts has yet to be achieved. Full article
(This article belongs to the Section Green Chemistry)
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Open AccessArticle New Metabolites of Coumarin Detected in Human Urine Using Ultra Performance Liquid Chromatography/Quadrupole-Time-of-Flight Tandem Mass Spectrometry
Molecules 2017, 22(11), 2031; https://doi.org/10.3390/molecules22112031
Received: 12 October 2017 / Revised: 12 November 2017 / Accepted: 17 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (2865 KB) | HTML Full-text | XML Full-text
Abstract
Coumarin (1,2-benzopyrone) is a natural compound whose metabolism in humans was established in the 1970s. However, a new metabolite was recently identified in human plasma, indicating that the metabolism of coumarin has not been completely elucidated. To complement the knowledge of its metabolism,
[...] Read more.
Coumarin (1,2-benzopyrone) is a natural compound whose metabolism in humans was established in the 1970s. However, a new metabolite was recently identified in human plasma, indicating that the metabolism of coumarin has not been completely elucidated. To complement the knowledge of its metabolism, a rapid and sensitive method using UPLC-QTOF-MS was developed. A total of 12 metabolites was identified using MetaboLynxTM software, including eight metabolites not previously reported in human urine. The identified biotransformation included hydroxylation, glucuronidation, sulfation, methylation, and conjugation with N-acetylcysteine. The present work demonstrates that the metabolism study of coumarin was incomplete, possibly due to limitations of old techniques. The identification of eight inedited metabolites of such a simple molecule suggests that the information regarding the metabolism of other drugs may also be incomplete, and therefore, new investigations are necessary. Full article
(This article belongs to the Special Issue Versatile Coumarins)
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Open AccessArticle The Rosiglitazone-Like Effects of Vitexilactone, a Constituent from Vitex trifolia L. in 3T3-L1 Preadipocytes
Molecules 2017, 22(11), 2030; https://doi.org/10.3390/molecules22112030
Received: 18 October 2017 / Revised: 8 November 2017 / Accepted: 17 November 2017 / Published: 22 November 2017
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Abstract
The increased number of patients with type 2 diabetes (T2D) has become a worldwide problem, and insulin sensitizers such as thiazolidinediones (TZDs) are used as therapeutic agents. We found that extracts of Vitex trifolia L. (V. trifolia), a medicinal plant from
[...] Read more.
The increased number of patients with type 2 diabetes (T2D) has become a worldwide problem, and insulin sensitizers such as thiazolidinediones (TZDs) are used as therapeutic agents. We found that extracts of Vitex trifolia L. (V. trifolia), a medicinal plant from Myanmar, induced adipogenesis similar to rosiglitazone (ROS), which is a TZD, in 3T3-L1 preadipocytes. In the present study, we attempted to isolate from V. trifolia those compounds that showed ROS-like effects. Among the extracts of hexane, ethyl acetate, and methanol obtained from V. trifolia, the ethyl acetate extract with the strongest ROS-like effects was purified by various chromatographic methods to obtain three known compounds: vitexilactone (1), vitexicarpin (2) and oleanolic acid (3). Among the isolated compounds, the ROS-like action of 1 was the strongest. The effects of 1 on 3T3-L1 cells during adipogenesis were compared with those of ROS. Both 1 and ROS increased lipid accumulation, the expression of adiponectin and GLUT4 in the cell membrane and decreased both the size of adipocytes and the phosphorylation of IRS-1, ERK1/2 and JNK in 3T3-L1 cells. In contrast, unlike ROS, the induction of proteins involved in lipogenesis was partial. ROS-like effects of 1 in 3T3-L1 cells were suppressed by the addition of bisphenol A diglycidyl ether (BADGE), one of a peroxisome proliferator-activated receptor γ (PPARγ) antagonists, suggesting that the action of 1 on adipocytes is mediated by PPARγ. From the results of the present study, it can be concluded that 1 is a novel insulin sensitizer candidate. Full article
(This article belongs to the collection Bioactive Compounds)
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Open AccessReview Dynamic Docking: A Paradigm Shift in Computational Drug Discovery
Molecules 2017, 22(11), 2029; https://doi.org/10.3390/molecules22112029
Received: 27 October 2017 / Revised: 18 November 2017 / Accepted: 19 November 2017 / Published: 22 November 2017
Cited by 2 | PDF Full-text (1630 KB) | HTML Full-text | XML Full-text
Abstract
Molecular docking is the methodology of choice for studying in silico protein-ligand binding and for prioritizing compounds to discover new lead candidates. Traditional docking simulations suffer from major limitations, mostly related to the static or semi-flexible treatment of ligands and targets. They also
[...] Read more.
Molecular docking is the methodology of choice for studying in silico protein-ligand binding and for prioritizing compounds to discover new lead candidates. Traditional docking simulations suffer from major limitations, mostly related to the static or semi-flexible treatment of ligands and targets. They also neglect solvation and entropic effects, which strongly limits their predictive power. During the last decade, methods based on full atomistic molecular dynamics (MD) have emerged as a valid alternative for simulating macromolecular complexes. In principle, compared to traditional docking, MD allows the full exploration of drug-target recognition and binding from both the mechanistic and energetic points of view (dynamic docking). Binding and unbinding kinetic constants can also be determined. While dynamic docking is still too computationally expensive to be routinely used in fast-paced drug discovery programs, the advent of faster computing architectures and advanced simulation methodologies are changing this scenario. It is feasible that dynamic docking will replace static docking approaches in the near future, leading to a major paradigm shift in in silico drug discovery. Against this background, we review the key achievements that have paved the way for this progress. Full article
(This article belongs to the Special Issue Frontiers in Computational Chemistry for Drug Discovery)
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Open AccessFeature PaperReview Synthesis of Spironucleosides: Past and Future Perspectives
Molecules 2017, 22(11), 2028; https://doi.org/10.3390/molecules22112028
Received: 16 October 2017 / Revised: 17 November 2017 / Accepted: 19 November 2017 / Published: 22 November 2017
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Abstract
Spironucleosides are a type of conformationally restricted nucleoside analogs in which the anomeric carbon belongs simultaneously to the sugar moiety and to the base unit. This locks the nucleic base in a specific orientation around the N-glycosidic bond, imposing restrictions on the
[...] Read more.
Spironucleosides are a type of conformationally restricted nucleoside analogs in which the anomeric carbon belongs simultaneously to the sugar moiety and to the base unit. This locks the nucleic base in a specific orientation around the N-glycosidic bond, imposing restrictions on the flexibility of the sugar moiety. Anomeric spiro-functionalized nucleosides have gained considerable importance with the discovery of hydantocidin, a natural spironucleoside isolated from fermentation broths of Streptomyces hygroscopicus which exhibits potent herbicidal activity. The biological activity of hydantocidin has prompted considerable synthetic interest in this nucleoside and also in a variety of analogues, since important pharmaceutical leads can be found among modified nucleoside analogues. We present here an overview of the most important advances in the synthesis of spironucleosides. Full article
(This article belongs to the Special Issue Advances in Spiro Compounds)
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Open AccessArticle Transformation of a Thermostable G-Quadruplex Structure into DNA Duplex Driven by Reverse Gyrase
Molecules 2017, 22(11), 2021; https://doi.org/10.3390/molecules22112021
Received: 8 November 2017 / Revised: 14 November 2017 / Accepted: 17 November 2017 / Published: 22 November 2017
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Abstract
Reverse gyrase is a topoisomerase that can introduce positive supercoils to its substrate DNA. It is demonstrated in our studies that a highly thermal stable G-quadruplex structure in a mini-plasmid DNA was transformed into its duplex conformation after a treatment with reverse gyrase.
[...] Read more.
Reverse gyrase is a topoisomerase that can introduce positive supercoils to its substrate DNA. It is demonstrated in our studies that a highly thermal stable G-quadruplex structure in a mini-plasmid DNA was transformed into its duplex conformation after a treatment with reverse gyrase. The structural difference of the topoisomers were verified and analyzed by gel electrophoresis, atomic force microscopy examination, and endonuclease digestion assays. All evidence suggested that the overwinding structure of positive supercoil could provide a driven force to disintegrate G-quadruplex and reform duplex. The results of our studies could suggest that hyperthermophiles might use reverse gyrase to manipulate the disintegration of non-B DNA structures and safekeep their genomic information. Full article
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Open AccessArticle Four New Glycosides from the Rhizoma of Anemarrhena asphodeloides
Molecules 2017, 22(11), 1995; https://doi.org/10.3390/molecules22111995
Received: 28 October 2017 / Accepted: 15 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (585 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Four new compounds, aneglycoside A–C (13) and timosaponin U (4), were isolated from the rhizomes of Anemarrhena asphodeloides. Their structures were determined through extensive spectroscopic analysis, chemical characteristics, and high-resolution mass spectrometry (HRMS). All the isolations
[...] Read more.
Four new compounds, aneglycoside A–C (13) and timosaponin U (4), were isolated from the rhizomes of Anemarrhena asphodeloides. Their structures were determined through extensive spectroscopic analysis, chemical characteristics, and high-resolution mass spectrometry (HRMS). All the isolations were evaluated for cytotoxicity against HepG2, Hela, and SGC7901 human cancer lines. Compounds 1, 2, and 4 showed weak antiproliferative activities on HepG2, Hela, and SGC7901 cells. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Application of Enzymatic Extracts from a CALB Standard Strain as Biocatalyst within the Context of Conventional Biodiesel Production Optimization
Molecules 2017, 22(11), 2025; https://doi.org/10.3390/molecules22112025
Received: 30 October 2017 / Revised: 16 November 2017 / Accepted: 18 November 2017 / Published: 21 November 2017
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Abstract
The application of biocatalysts in the transesterification process of triglycerides (TG) allows integrating the glycerol in the form of monoglyceride (MG), sharply increasing the yield and the environmental sustainability of the conventional biodiesel production process. This is known as Ecodiesel. To overcome the
[...] Read more.
The application of biocatalysts in the transesterification process of triglycerides (TG) allows integrating the glycerol in the form of monoglyceride (MG), sharply increasing the yield and the environmental sustainability of the conventional biodiesel production process. This is known as Ecodiesel. To overcome the inconvenient of the high cost of the currently employed highly purified commercial enzymes, the use of scarcely purified extracts obtained from standard strains of the same species of commercial lipases currently applied in this process is being investigated. Thus, Candida antarctica type B (CALB) was chosen to determine the optimal conditions of culture of this yeast. The standard strain was obtained from the Spanish Type Microbial Cultures Collection (CECT) and has been used to carry out several studies to elucidate its optimum growth conditions. Through a process of lyophilization with prior dialysis of the liquid cultures, the enzymatic extracts were obtained. The different obtained cultures have been applied as biocatalysts in the 1,3-selective transesterification reaction of sunflower oil with ethanol to obtain Ecodiesel (FAEE + MG). Selectivity and reaction yields were obtained by gas chromatography. Acceptable yields are obtained during the reaction time as well as in successive reactions, demonstrating the feasibility of using these CALB enzymatic extracts as biocatalysts. Full article
(This article belongs to the Special Issue Meeting of the Spanish Catalysis Society (SECAT’17))
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