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Molecules, Volume 18, Issue 11 (November 2013), Pages 13124-14454

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Open AccessArticle Determination and Comparison of Seed Oil Triacylglycerol Composition of Various Soybeans (Glycine max (L.)) Using 1H-NMR Spectroscopy
Molecules 2013, 18(11), 14448-14454; https://doi.org/10.3390/molecules181114448
Received: 15 September 2013 / Revised: 2 November 2013 / Accepted: 12 November 2013 / Published: 21 November 2013
Cited by 4 | PDF Full-text (319 KB) | HTML Full-text | XML Full-text
Abstract
Seed oil triacylglycerol (TAG) composition of 32 soybean varieties were determined and compared using 1H-NMR. The contents of linolenic (Ln), linoleic (L), and oleic (O) ranged from 10.7% to 19.3%, 37.4%–50.1%, and 15.7%–34.1%, respectively. As is evident, linoleic acid was the major
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Seed oil triacylglycerol (TAG) composition of 32 soybean varieties were determined and compared using 1H-NMR. The contents of linolenic (Ln), linoleic (L), and oleic (O) ranged from 10.7% to 19.3%, 37.4%–50.1%, and 15.7%–34.1%, respectively. As is evident, linoleic acid was the major fatty acid of soybean oil. Compositional differences among the varieties were observed. Natural oils containing unsaturated groups have been regarded as important nutrient and cosmetic ingredients because of their various biological activities. The TAG profiles of the soy bean oils could be useful for distinguishing the origin of seeds and controlling the quality of soybean oils. To the best of our knowledge, this is the first study in which the TAG composition of various soybean oils has been analyzed using the 1H-NMR method. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA)
Molecules 2013, 18(11), 14430-14447; https://doi.org/10.3390/molecules181114430
Received: 15 October 2013 / Revised: 13 November 2013 / Accepted: 19 November 2013 / Published: 21 November 2013
Cited by 3 | PDF Full-text (1560 KB) | HTML Full-text | XML Full-text
Abstract
Dynamic atroposelective resolution of chiral salts derived from oily racemic nicotinamides and enantiopure dibenzoyltartaric acid (DBTA) was achieved by crystallization. The absolute structures of the axial chiral nicotinamides were determined by X-ray structural analysis. The chirality could be controlled by the selection of
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Dynamic atroposelective resolution of chiral salts derived from oily racemic nicotinamides and enantiopure dibenzoyltartaric acid (DBTA) was achieved by crystallization. The absolute structures of the axial chiral nicotinamides were determined by X-ray structural analysis. The chirality could be controlled by the selection of enantiopure DBTA as a chiral auxiliary. The axial chirality generated by dynamic salt formation was retained for a long period after dissolving the chiral salt in solution even after removal of the chiral acid. The rate of racemization of nicotinamides could be controlled based on the temperature and solvent properties, and that of the salts was prolonged compared to free nicotinamides, as the molecular structure of the pyridinium ion in the salts was different from that of acid-free nicotinamides. Full article
(This article belongs to the Special Issue Dynamic Stereochemistry)
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Open AccessArticle Solution Structure of the Circular γ-Domain Analog from the Wheat Metallothionein Ec-1
Molecules 2013, 18(11), 14414-14429; https://doi.org/10.3390/molecules181114414
Received: 16 October 2013 / Revised: 6 November 2013 / Accepted: 19 November 2013 / Published: 21 November 2013
Cited by 7 | PDF Full-text (3029 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The first cyclic analog of a metallothionein (MT) was prepared and analyzed by UV and (magnetic) circular dichroism spectroscopy, ESI-MS as well as NMR spectroscopy. Results reveal that the evaluated cyclic g-Ec-1 domain of the wheat MT Ec-1 retains
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The first cyclic analog of a metallothionein (MT) was prepared and analyzed by UV and (magnetic) circular dichroism spectroscopy, ESI-MS as well as NMR spectroscopy. Results reveal that the evaluated cyclic g-Ec-1 domain of the wheat MT Ec-1 retains its ability to coordinate two Zn(II) or Cd(II) ions and adopts a three-dimensional structure that is highly similar to the one of the linear wild-type form. However, the reduced flexibility of the protein backbone facilitates structure solution significantly and results in a certain stabilization of metal binding to the protein. Full article
(This article belongs to the Special Issue NMR of Proteins and Small Biomolecules)
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Open AccessArticle Biological Activity of Propolis-Honey Balm in the Treatment of Experimentally-Evoked Burn Wounds
Molecules 2013, 18(11), 14397-14413; https://doi.org/10.3390/molecules181114397
Received: 23 September 2013 / Revised: 11 November 2013 / Accepted: 12 November 2013 / Published: 21 November 2013
Cited by 11 | PDF Full-text (2782 KB) | HTML Full-text | XML Full-text
Abstract
Medicines of biogenic origin with micro-organic, regenerative and analgesic properties are becoming more and more significant in the treatment of burn wounds. These properties are found in apitherapeutics such as propolis and honey—products collected and processed by a honey bee. Their effect on
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Medicines of biogenic origin with micro-organic, regenerative and analgesic properties are becoming more and more significant in the treatment of burn wounds. These properties are found in apitherapeutics such as propolis and honey—products collected and processed by a honey bee. Their effect on the course of the healing processes is multidirectional. The aim of the study was a histopathological and biochemical analysis of the processes of scar formation in experimentally evoked burn wounds in white pigs treated with the 1% and 3% Sepropol balms containing standardized extracts of propolis and honey. The results were compared with the therapeutic effects obtained with dermazin cream (1% silver sulfadiazine). The level of collagen was determined in the wounds treated with 1% and 3% Sepropol and compared with the collagen level in healthy skin and wounds treated with dermazin. Granulation and regenerated epithelium formation times were compared, with the 3% Sepropol being by far the most effective. The 3% Sepropol also increased the collagen level to 116% with the control sub-groups scoring between 80% and 98%. The results show the healing process of burn wounds in pigs treated with the Sepropol balm starts earlier and has a faster course than the standard dermazin therapy. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle An In Vitro Study of the Antimicrobial Effects of Indigo Naturalis Prepared from Strobilanthes formosanus Moore
Molecules 2013, 18(11), 14381-14396; https://doi.org/10.3390/molecules181114381
Received: 10 September 2013 / Revised: 24 October 2013 / Accepted: 25 October 2013 / Published: 21 November 2013
Cited by 9 | PDF Full-text (517 KB) | HTML Full-text | XML Full-text
Abstract
Indigo naturalis is effective in treating nail psoriasis coexisting with microorganism infections. This study examines the antimicrobial effects of indigo naturalis prepared from Strobilanthes formosanus Moore. Eight bacterial and seven fungal strains were assayed using the agar diffusion method to examine the effects
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Indigo naturalis is effective in treating nail psoriasis coexisting with microorganism infections. This study examines the antimicrobial effects of indigo naturalis prepared from Strobilanthes formosanus Moore. Eight bacterial and seven fungal strains were assayed using the agar diffusion method to examine the effects of indigo naturalis and its bioactive compounds. The bioactive compounds of indigo naturalis were purified sequentially using GFC, TLC, and HPLC. Their structures were identified using mass spectrometry and NMR spectroscopy. UPLC-MS/MS was applied to compare the metabolome profiles of indigo naturalis ethyl-acetate (EA) extract and its source plant, Strobilanthes formosanus Moore. The results of in vitro antimicrobial assays showed that indigo naturalis EA-extract significantly (≥1 mg/disc) inhibits Gram-positive bacteria (Staphylococcus aureus, S. epidermis and methicillin-resistant S. aureus (MRSA)) and mildly inhibits non-dermatophytic onychomycosis pathogens (Aspergillus fumigates and Candida albicans), but has little effect on dermatophyes. Isatin and tryptanthrin were identified as the bioactive compounds of indigo naturalis using S. aureus and S. epidermis as the bioassay model. Both bioactive ingredients had no effect on all tested fungi. In summary, indigo naturalis prepared from Strobilanthes formosanus Moore exhibits antimicrobial effects on Staphylococcus and non-dermatophytic onychomycosis pathogens. Tryptanthrin and isatin may be its major bioactive ingredients against Staphylococcus and the inhibitory effect on MRSA may be due to other unidentified ingredients. Full article
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Open AccessArticle Optimization of Extraction of Novel Pectinase Enzyme Discovered in Red Pitaya (Hylocereus polyrhizus) Peel
Molecules 2013, 18(11), 14366-14380; https://doi.org/10.3390/molecules181114366
Received: 20 August 2013 / Revised: 20 October 2013 / Accepted: 1 November 2013 / Published: 20 November 2013
Cited by 10 | PDF Full-text (371 KB) | HTML Full-text | XML Full-text
Abstract
Plant peels could be a potential source of novel pectinases for use in various industrial applications due to their broad substrate specificity with high stability under extreme conditions. Therefore, the extraction conditions of a novel pectinase enzyme from pitaya peel was optimized in
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Plant peels could be a potential source of novel pectinases for use in various industrial applications due to their broad substrate specificity with high stability under extreme conditions. Therefore, the extraction conditions of a novel pectinase enzyme from pitaya peel was optimized in this study. The effect of extraction variables, namely buffer to sample ratio (2:1 to 8:1, X1), extraction temperature (−15 to +25 °C, X2) and buffer pH (4.0 to 12.0, X3) on specific activity, temperature stability, storage stability and surfactant agent stability of pectinase from pitaya peel was investigated. The study demonstrated that the optimum conditions for the extraction of pectinase from pitaya sources could improve the enzymatic characteristics of the enzyme and protect its activity and stability during the extraction procedure. The optimum extraction conditions cause the pectinase to achieve high specific activity (15.31 U/mg), temperature stability (78%), storage stability (88%) and surfactant agent stability (83%). The most desirable conditions to achieve the highest activity and stability of pectinase enzyme from pitaya peel were the use of 5:1 buffer to sample ratio at 5 °C and pH 8.0. Full article
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Open AccessArticle Modulation of the Microenvironment Surrounding the Active Site of Penicillin G Acylase Immobilized on Acrylic Carriers Improves the Enzymatic Synthesis of Cephalosporins
Molecules 2013, 18(11), 14349-14365; https://doi.org/10.3390/molecules181114349
Received: 9 September 2013 / Revised: 20 October 2013 / Accepted: 28 October 2013 / Published: 20 November 2013
Cited by 12 | PDF Full-text (648 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The catalytic properties of penicillin G acylase (PGA) from Escherichia coli in kinetically controlled synthesis of β-lactam antibiotics are negatively affected upon immobilization on hydrophobic acrylic carriers. Two strategies have been here pursued to improve the synthetic performance of PGA immobilized on epoxy-activated
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The catalytic properties of penicillin G acylase (PGA) from Escherichia coli in kinetically controlled synthesis of β-lactam antibiotics are negatively affected upon immobilization on hydrophobic acrylic carriers. Two strategies have been here pursued to improve the synthetic performance of PGA immobilized on epoxy-activated acrylic carriers. First, an aldehyde-based spacer was inserted on the carrier surface by glutaraldehyde activation (immobilization yield = 50%). The resulting 3-fold higher synthesis/hydrolysis ratio (vs/vh1 = 9.7 ± 0.7 and 10.9 ± 0.7 for Eupergit® C and Sepabeads® EC-EP, respectively) with respect to the unmodified support (vs/vh1 = 3.3 ± 0.4) was ascribed to a facilitated diffusion of substrates and products as a result of the increased distance between the enzyme and the carrier surface. A second series of catalysts was prepared by direct immobilization of PGA on epoxy-activated acrylic carriers (Eupergit® C), followed by quenching of oxiranes not involved in the binding with the protein with different nucleophiles (amino acids, amines, amino alcohols, thiols and amino thiols). In most cases, this derivatization increased the synthesis/hydrolysis ratio with respect to the non derivatized carrier. Particularly, post-immobilization treatment with cysteine resulted in about 2.5-fold higher vs/vh1 compared to the untreated biocatalyst, although the immobilization yield decreased from 70% (untreated Eupergit® C) to 20%. Glutaraldehyde- and cysteine-treated Eupergit® C catalyzed the synthesis of cefazolin in 88% (±0.9) and 87% (±1.6) conversion, respectively, whereas untreated Eupergit® C afforded this antibiotic in 79% (±1.2) conversion. Full article
(This article belongs to the Special Issue Enzyme Chemistry)
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Open AccessCommunication Antibacterial Activity of Glucomoringin Bioactivated with Myrosinase against Two Important Pathogens Affecting the Health of Long-Term Patients in Hospitals
Molecules 2013, 18(11), 14340-14348; https://doi.org/10.3390/molecules181114340
Received: 25 October 2013 / Revised: 8 November 2013 / Accepted: 11 November 2013 / Published: 20 November 2013
Cited by 23 | PDF Full-text (1071 KB) | HTML Full-text | XML Full-text
Abstract
Glucosinolates (GLs) are natural compounds present in species of the order Brassicales and precursors of bioactive isothiocyanates (ITCs). In the recent years, they have been studied mainly for their chemopreventive as well as novel chemotherapeutics properties. Among them 4-(α-L-rhamnosyloxy)benzyl glucosinolate (glucomoringin; GMG), purified
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Glucosinolates (GLs) are natural compounds present in species of the order Brassicales and precursors of bioactive isothiocyanates (ITCs). In the recent years, they have been studied mainly for their chemopreventive as well as novel chemotherapeutics properties. Among them 4-(α-L-rhamnosyloxy)benzyl glucosinolate (glucomoringin; GMG), purified from seeds of Moringa oleifera Lam., a plant belonging to the Moringaceae family, represents an uncommon member of the GL family with peculiar characteristics. This short communication reports new evidences about the properties of GMG and presents a new innovative utilization of the molecule. The bioactivation of GMG by myrosinase enzyme just before treatment, permits to maximize the power of the final product of the reaction, which is the 4-(α-L-rhamnosyloxy)benzyl isothiocyanate (GMG-ITC). We tested the antibiotic activity of this latter compound on two strains of pathogens affecting the health of patients in hospital, namely Staphylococcus aureus and Enterococcus casseliflavus, and on the yeast Candida albicans. Results show that the sensibility of S. aureus BAA-977 strain and E. casseliflavus to GMG-ITC treatment reveals an important possible application of this molecule in the clinical care of patients, more and more often resistant to traditional therapies. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Tuning a 96-Well Microtiter Plate Fluorescence-Based Assay to Identify AGE Inhibitors in Crude Plant Extracts
Molecules 2013, 18(11), 14320-14339; https://doi.org/10.3390/molecules181114320
Received: 12 October 2013 / Revised: 7 November 2013 / Accepted: 14 November 2013 / Published: 19 November 2013
Cited by 25 | PDF Full-text (619 KB) | HTML Full-text | XML Full-text
Abstract
Advanced glycation end-products (AGEs) are involved in the pathogenesis of numerous diseases. Among them, cellular accumulation of AGEs contributes to vascular complications in diabetes. Besides using drugs to lower blood sugar, a balanced diet and the intake of herbal products potentially limiting AGE
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Advanced glycation end-products (AGEs) are involved in the pathogenesis of numerous diseases. Among them, cellular accumulation of AGEs contributes to vascular complications in diabetes. Besides using drugs to lower blood sugar, a balanced diet and the intake of herbal products potentially limiting AGE formation could be considered beneficial for patients’ health. The current paper presents a simple and cheap high-throughput screening (HTS) assay based on AGE fluorescence and suitable for plant extract screening. We have already implemented an HTS assay based on vesperlysines-like fluorescing AGEs quickly (24 h) formed from BSA and ribose under physiological conditions. However, interference was noted when fluorescent compounds and/or complex mixtures were tested. To overcome these problems and apply this HTS assay to plant extracts, we developed a technique for systematic quantification of both vesperlysines (λexc 370 nm; λem 440 nm) and pentosidine-like (λexc 335 nm; λem 385 nm) AGEs. In a batch of medicinal and food plant extracts, hits were selected as soon as fluorescence decreased under a fixed threshold for at least one wavelength. Hits revealed during this study appeared to contain well-known and powerful anti-AGE substances, thus demonstrating the suitability of this assay for screening crude extracts (0.1 mg/mL). Finally, quercetin was found to be a more powerful reference compound than aminoguanidine in such assay. Full article
(This article belongs to the Section Natural Products Chemistry)
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Open AccessArticle Synthesis of Quaternary Heterocyclic Salts
Molecules 2013, 18(11), 14306-14319; https://doi.org/10.3390/molecules181114306
Received: 7 October 2013 / Revised: 28 October 2013 / Accepted: 28 October 2013 / Published: 19 November 2013
Cited by 9 | PDF Full-text (301 KB) | HTML Full-text | XML Full-text
Abstract
The microwave synthesis of twenty quaternary ammonium salts is described. The syntheses feature comparable yields to conventional synthetic methods reported in the current literature with reduced reaction times and the absence of solvent or minimal solvent. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessCommunication The Formation of 2,2,4-Trimethyl-2,3-dihydro-1H-1,5-Benzodiazepine from 1,2-Diaminobenzene in the Presence of Acetone
Molecules 2013, 18(11), 14293-14305; https://doi.org/10.3390/molecules181114293
Received: 11 September 2013 / Revised: 11 November 2013 / Accepted: 11 November 2013 / Published: 19 November 2013
Cited by 1 | PDF Full-text (376 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In an attempt to synthesize a 2-substituted benzimidazole from the reaction of o-phenylenediamine and isophthalic acid in the presence of acetone and ethanol under microwave irradiation, a salt of the isophthalate ion and 2,2,4-trimethyl-2,3-dihydro-1H-1,5-benzodiazepin-5-ium ion was obtained. The condensation of
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In an attempt to synthesize a 2-substituted benzimidazole from the reaction of o-phenylenediamine and isophthalic acid in the presence of acetone and ethanol under microwave irradiation, a salt of the isophthalate ion and 2,2,4-trimethyl-2,3-dihydro-1H-1,5-benzodiazepin-5-ium ion was obtained. The condensation of two moles of acetone with the amine groups resulted in the formation of the benzodiazepine which crystallized as an iminium cation forming a salt with the isophthalate anion. The formation of benzodiazepine was also confirmed by performing the reaction of o-phenylenediamine with excess acetone in ethanol under conventional heating conditions. The compounds were characterized by NMR, FTIR, HRMS and microanalysis as well as X-ray crystallography. The reaction mechanism leading to the formation of benzodiazepine is also discussed. Full article
(This article belongs to the Section Organic Chemistry)
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Open AccessArticle Triterpenoids and Steroids from Ganoderma mastoporum and Their Inhibitory Effects on Superoxide Anion Generation and Elastase Release
Molecules 2013, 18(11), 14285-14292; https://doi.org/10.3390/molecules181114285
Received: 27 September 2013 / Revised: 6 November 2013 / Accepted: 15 November 2013 / Published: 19 November 2013
Cited by 3 | PDF Full-text (212 KB) | HTML Full-text | XML Full-text
Abstract
The methanol extracts of the fruiting bodies of Ganoderma mastoporum collected in Vietnam was purified to afford eight compounds, including three triterpenoids and five steroids. The purified compounds were examined for their inhibitory effects against superoxide anion generation and elastase release. Among the
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The methanol extracts of the fruiting bodies of Ganoderma mastoporum collected in Vietnam was purified to afford eight compounds, including three triterpenoids and five steroids. The purified compounds were examined for their inhibitory effects against superoxide anion generation and elastase release. Among the tested compounds, ergosta-4,6,8(14),22-tetraen-3-one (3) exhibited the most significant inhibition towards superoxide anion generation and elastase release with IC50 values of 2.30 ± 0.38 and 1.94 ± 0.50 µg/mL, respectively. Full article
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Open AccessReview Synthesis of DNA/RNA and Their Analogs via Phosphoramidite and H-Phosphonate Chemistries
Molecules 2013, 18(11), 14268-14284; https://doi.org/10.3390/molecules181114268
Received: 8 October 2013 / Revised: 8 November 2013 / Accepted: 8 November 2013 / Published: 18 November 2013
Cited by 26 | PDF Full-text (680 KB) | HTML Full-text | XML Full-text
Abstract
The chemical synthesis of DNA and RNA is universally carried out using nucleoside phosphoramidites or H-phosphonates as synthons. This review focuses on the phosphorus chemistry behind these synthons and how it has been developed to generate procedures whereby yields per condensation approach 100%
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The chemical synthesis of DNA and RNA is universally carried out using nucleoside phosphoramidites or H-phosphonates as synthons. This review focuses on the phosphorus chemistry behind these synthons and how it has been developed to generate procedures whereby yields per condensation approach 100% with very few side products. Additionally the synthesis and properties of certain DNA and RNA analogs that are modified at phosphorus will also be discussed. These analogs include boranephosphonates, metallophosphonates, and alkylboranephosphines. Full article
(This article belongs to the Special Issue Organophosphorus Chemistry)
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Open AccessArticle Gold Nanoparticles on Mesoporous SiO2-Coated Magnetic Fe3O4 Spheres: A Magnetically Separatable Catalyst with Good Thermal Stability
Molecules 2013, 18(11), 14258-14267; https://doi.org/10.3390/molecules181114258
Received: 22 October 2013 / Revised: 11 November 2013 / Accepted: 12 November 2013 / Published: 18 November 2013
Cited by 8 | PDF Full-text (1299 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Fe3O4 spheres with an average size of 273 nm were prepared in the presence of CTAB by a solvothermal method. The spheres were modified by a thin layer of SiO2, and then coated by mesoporous SiO2 (m-SiO
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Fe3O4 spheres with an average size of 273 nm were prepared in the presence of CTAB by a solvothermal method. The spheres were modified by a thin layer of SiO2, and then coated by mesoporous SiO2 (m-SiO2) films, by using TEOS as a precursor and CTAB as a soft template. The resulting m-SiO2/Fe3O4 spheres, with an average particle size of 320 nm, a high surface area (656 m2/g), and ordered nanopores (average pore size 2.5 nm), were loaded with gold nanoparticles (average size 3.3 nm). The presence of m-SiO2 coating could stabilize gold nanoparticles against sintering at 500 °C. The material showed better performance than a conventional Au/SiO2 catalyst in catalytic reduction of p-nitrophenol with NaBH4. It can be separated from the reaction mixture by a magnet and be recycled without obvious loss of catalytic activity. Relevant characterization by XRD, TEM, N2 adsorption-desorption, and magnetic measurements were conducted. Full article
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Open AccessArticle Simultaneous Determination of 14 Phenolic Compounds in Grape Canes by HPLC-DAD-UV Using Wavelength Switching Detection
Molecules 2013, 18(11), 14241-14257; https://doi.org/10.3390/molecules181114241
Received: 18 September 2013 / Revised: 7 November 2013 / Accepted: 13 November 2013 / Published: 18 November 2013
Cited by 16 | PDF Full-text (594 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The paper described a novel chromatographic method for the simultaneous determination of phenolic compounds such as gallic, protocatechuic, vanillic, caffeic, syringic, p-coumaric and salicylic acid, (+)-catechin, (‒)-epicatechin, rutin, morin, quercetin, coumarin and trans-resveratrol at their maximum absorbance wavelengths (MAW) employing reverse-phase
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The paper described a novel chromatographic method for the simultaneous determination of phenolic compounds such as gallic, protocatechuic, vanillic, caffeic, syringic, p-coumaric and salicylic acid, (+)-catechin, (‒)-epicatechin, rutin, morin, quercetin, coumarin and trans-resveratrol at their maximum absorbance wavelengths (MAW) employing reverse-phase high performance liquid chromatography combined with DAD and UV detection via detection wavelength switching. The method was based on MAW acquisition by DAD and quantification by UV. The separation process was performed on a Shim-Pack VP-ODS C18 column (250 mm × 4.6 mm, 5 μm) held at 30 °C, utilizing 3.0% acetic acid and acetonitrile as mobile phase at a flow rate of 0.8 mL/min in the gradient elution mode. The method was fully validated in terms of linearity (r2 > 0.9990, 10‒350 mg/L), precision (both intra-day and inter-day RSD < 4.22%), accuracy (97.31%‒104.66%), specificity, robustness (0.59% < RSD < 2.86%), limit of detection and quantification. The switching method significantly improved the sensitivities of most phenolics studied in comparison with the standard constant wavelength detection (280 nm). The proposed method has been successfully applied to the determination of 14 phenolic compounds in 89 varieties of one-year-old Chinese grape one-year-canes. Grape canes contain many phenolics, especially trans-resveratrol, (‒)-epicatechin, and (+)-catechin. Full article
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