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1.
Int J Mol Sci ; 25(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542218

RESUMO

This study addresses the pressing issues of energy production and consumption, in line with global sustainable development goals. Focusing on the potential of alcohols as "green" alternatives to traditional fossil fuels, especially in biofuel applications, we investigate the thermochemical properties of three alcohols (n-propanol, n-butanol, n-pentanol) blended with sunflower oil. The calorimetric analysis allows for the experimental determination of excess enthalpies in pseudo-binary mixtures at 303.15 K, revealing similarities in the trends of the curves (dependence on concentrations) but with different values for the excess enthalpies for each mixture. Despite the structural differences of the alcohols studied, the molar excess enthalpy values exhibit uniformity, suggesting consistent mixing behavior. The peak values of excess enthalpies for systems with sunflower oil and n-propanol, n-butanol and n-pentanol are, respectively, 3255.2 J/mole, 3297.4 J/mole and 3150.1 J/mole. Both the NRTL and Redlich-Kister equations show satisfactory agreement with the obtained values.


Assuntos
Álcoois , Biocombustíveis , Pentanóis , Álcoois/química , Óleo de Girassol , 1-Propanol , 1-Butanol
2.
Biomacromolecules ; 25(3): 1709-1723, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38377481

RESUMO

Polysaccharide nanoporous structures are suitable for various applications, ranging from biomedical scaffolds to adsorption materials, owing to their biocompatibility and large surface areas. Pectin, in particular, can create 3D nanoporous structures in aqueous solutions by binding with calcium cations and creating nanopores by phase separation; this process involves forming hydrogen bonds between alcohols and pectin chains in water and alcohol mixtures and the resulting penetration of alcohols into calcium-bound pectin gels. However, owing to the dehydration and condensation of polysaccharide chains during drying, it has proven to be challenging to maintain the 3D nanoporous structure without using a freeze-drying process or supercritical fluid. Herein, we report a facile method for creating polysaccharide-based xerogels, involving the co-evaporation of water with a nonsolvent (e.g., a low-molecular-weight hydrophobic alcohol such as isopropyl or n-propyl alcohol) at ambient conditions. Experiments and coarse-grained molecular dynamics simulations confirmed that salt-induced phase separation and hydrogen bonding between hydrophobic alcohols and pectin chains were the dominant processes in mixtures of pectin, water, and hydrophobic alcohols. Furthermore, the azeotropic evaporation of water and alcohol mixed in approximately 1:1 molar ratios was maintained during the natural drying process under ambient conditions, preventing the hydration and aggregation of the hydrophilic pectin chains. These results introduce a simple and convenient process to produce 3D polysaccharide xerogels under ambient conditions.


Assuntos
Cálcio , Nanoporos , Cálcio/química , Pectinas/química , Separação de Fases , Água/química , Cloreto de Sódio , Álcoois/química
3.
Plant Physiol Biochem ; 198: 107679, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37121165

RESUMO

Plant cuticles cover aerial organs to limit non-stomatal water loss and protect against insects and pathogens. Cuticles contain complex mixtures of fatty acid-derived waxes, with various chain lengths and diverse functional groups. To further our understanding of the chemical diversity and biosynthesis of these compounds, this study investigated leaf cuticular waxes of Welsh onion (Allium fistulosum L.) wild type and a wax-deficient mutant. Leaf waxes were extracted with chloroform, separated using thin layer chromatography (TLC), and analyzed using gas chromatography-mass spectrometry (GC-MS). The extracts contained typical wax compound classes found in nearly all plant lineages but also two uncommon compound classes. Analyses of characteristic MS fragmentation patterns followed by comparisons with synthetic standards identified the latter as very-long-chain ketones and primary ketols. The ketols were minor compounds, with chain lengths ranging from C28 to C32 and carbonyls mainly on C-18 and C-20 in wild type wax, and a C28 chain with C-16 carbonyl in the mutant. The ketones made up 70% of total wax in the wild type, consisting mainly of C31 isomers with carbonyl group on C-14 or C-16. In contrast, the mutant wax comprised only 4% ketones, with chain lengths C27 and C29 and carbonyls predominantly on C-12 and C-14, respectively. A two-carbon homolog shift between wild type and mutant was also observed in the primary alcohols (a major wax compound class), whilst alkanes exhibited a four-carbon shift. Overall, the compositional data shed light on possible biosynthetic pathways to wax ketones that can be tested in future studies.


Assuntos
Allium , Ceras , Ceras/metabolismo , Cebolas/genética , Cebolas/metabolismo , Allium/metabolismo , Álcoois/análise , Álcoois/química , Álcoois/metabolismo , Folhas de Planta/metabolismo , Cetonas/análise , Cetonas/química , Cetonas/metabolismo , Carbono/metabolismo
4.
ChemistryOpen ; 11(11): e202100294, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35261188

RESUMO

The substitution reaction of phosphinates with a binaphthyloxy group at the phosphorus atom with lithium alkoxides proceeded with good to high efficiencies to give P-chirogenic phosphinates with a high enantiomeric ratio. As alcohols, primary, secondary, and tertiary alcohols could be used, and the use of tert-butyl alcohol yielded the products with a higher enantiomeric ratio. A substrate with two different alkyl groups on the phosphorus atom could also participate in the substitution reaction to give the corresponding products in good yields with excellent selectivity. The molecular structures of one of the substrates and the corresponding products, determined by X-ray analyses, proved that the substitution reaction at the phosphorus atom proceeded with inversion of the absolute configuration. The usefulness of the reaction was demonstrated by using it to prepare a drug candidate for Duchenne muscular dystrophy. Finally, thionation of the resulting phosphinates was carried out to form P-chirogenic phosphinothioates.


Assuntos
Álcoois , Fósforo , Estereoisomerismo , Estrutura Molecular , Álcoois/química , Fósforo/química , Esterificação
5.
J Oleo Sci ; 71(2): 201-213, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35034941

RESUMO

Baru (Dipteryx alata) almond is an emerging nut from the Brazilian savannah, that presents unique flavor and an interesting specialty oil. In this study, we aimed at investigating the effects of pressure, temperature, type (alcohol and/or water), and concentration of polar cosolvent on the extraction yield and tocopherol contents of baru oil obtained by supercritical-CO2 extraction (SC-CO2); and to investigate the effect of temperature and pressure on phytosterol, phenolic, and volatile compounds' profile in the oil when H2O was the cosolvent. Baru oil extracted with SC-CO2 using alcohol as a cosolvent showed a higher extraction yield (20.5-31.1%) than when using H2O (4.16-22.7%). However, when 0.3% H2O was used as cosolvent, baru oils presented the highest γ-tocopherol (107 and 43.7 mg/100 g) and total tocopherol (212 and 48.7 mg/100 g) contents, depending on the temperature and pressure used (50°C and 10 MPa or 70°C and 30 MPa, respectively). Consequently, the lowest pressure (10 MPa) and temperature (50°C) values resulted in baru oils with better γ/α-ratio, and the highest contents of ß-sitosterol (107 mg/100 g) and phenolic compounds (166 mg/100 g). However, the highest pressure (30 MPa) and temperature (70°C) values improved the volatile profile of oils. Therefore, although alcohol as a cosolvent improved oil yield, small amounts of H2O provided a value-added baru oil with either high content of bioactive compounds or with a distinctive volatile profile by tuning temperature and pressure used during SC-CO2 extraction.


Assuntos
Dióxido de Carbono/química , Dipteryx/química , Extração Líquido-Líquido/métodos , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Solventes/química , Tocoferóis/análise , Água/química , Álcoois/química , Hidroxibenzoatos/análise , Fitosteróis/análise , Pressão , Temperatura , Compostos Orgânicos Voláteis/análise
6.
Molecules ; 28(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36615417

RESUMO

Benzylic alcohols are among the most important intermediates in organic synthesis. Recently, the use of abundant metals has attracted significant attention due to the issues with the scarcity of platinum group metals. Herein, we report a sequential method for the synthesis of benzylic alcohols by a merger of iron catalyzed cross-coupling and highly chemoselective reduction of benzamides promoted by sodium dispersion in the presence of alcoholic donors. The method has been further extended to the synthesis of deuterated benzylic alcohols. The iron-catalyzed Kumada cross-coupling exploits the high stability of benzamide bonds, enabling challenging C(sp2)-C(sp3) cross-coupling with alkyl Grignard reagents that are prone to dimerization and ß-hydride elimination. The subsequent sodium dispersion promoted reduction of carboxamides proceeds with full chemoselectivity for the C-N bond cleavage of the carbinolamine intermediate. The method provides access to valuable benzylic alcohols, including deuterium-labelled benzylic alcohols, which are widely used as synthetic intermediates and pharmacokinetic probes in organic synthesis and medicinal chemistry. The combination of two benign metals by complementary reaction mechanisms enables to exploit underexplored avenues for organic synthesis.


Assuntos
Amidas , Ferro , Ferro/química , Catálise , Álcool Benzílico , Oxirredução , Álcoois/química
7.
Molecules ; 26(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34885667

RESUMO

Lilac aldehydes are considered as principal olfactory molecules of lilac flowers. We have designed, prepared, and evaluated a set of racemic seco-analogues of such natural products. The synthesis employs commercially available α-chloroketones as substrates that are transformed in four steps to target compounds. Their qualitative olfactory analysis revealed that the opening of the tetrahydrofuran ring leads to a vanishing of original flowery scent with the emergence of spicy aroma accompanied by green notes, and/or fruity aspects of novel seco-analogues. These results suggest the important osmophoric role of THF moiety for the generation of the typical flowery aroma associated with lilac aldehydes.


Assuntos
Aldeídos/química , Aldeídos/síntese química , Produtos Biológicos/química , Produtos Biológicos/síntese química , Flores/química , Odorantes/análise , Óleos de Plantas/química , Olfato , Syringa/química , Álcoois/química , Alcenos/química , Furanos/química , Ácidos Levulínicos/química , Monoterpenos/química
8.
Molecules ; 26(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34684840

RESUMO

Fresh roselle are high in moisture and deteriorate easily, which makes drying important for extending shelf-life and increasing availability. This study investigated the influence of different drying methods (oven-drying, freeze-drying, vacuum-drying, and sun-drying) on the quality of roselle calyx expressed as physicochemical properties (moisture content, water activity, soluble solids, color), volatile compounds, and microstructure. Oven-drying and freeze-drying reduced moisture content most while vacuum-drying and sun-drying were not as efficient. All drying methods except sun-drying resulted in water activities low enough to ensure safety and quality. Vacuum-drying had no impact on color of the dry calyx and only small impact on color of water extract of calyx. Drying reduced terpenes, aldehydes, and esters but increased furans. This is expected to reduce fruity, floral, spicy, and green odors and increase caramel-like aroma. Sun-drying produced more ketones, alcohols, and esters. Scanning electron microscopy revealed that freeze-drying preserved the cell structure better, and freeze-dried samples resembled fresh samples most compared to other drying techniques. The study concludes that freeze-drying should be considered as a suitable drying method, especially with respect to preservation of structure.


Assuntos
Flores/química , Hibiscus/química , Odorantes/análise , Compostos Orgânicos Voláteis/química , Álcoois/química , Aldeídos/química , Dessecação/métodos , Ésteres/química , Liofilização/métodos , Frutas/química , Cetonas/química , Extratos Vegetais/química , Terpenos/química
9.
Molecules ; 26(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34684892

RESUMO

Ulomoides dermestoides are used as a broad-spectrum medical insect in the alternative treatment of various diseases. Preliminary volatilome studies carried out to date have shown, as the main components, methyl-1,4-benzoquinone, ethyl-1,4-benzoquinone, 1-tridecene, 1-pentadecene, and limonene. This work focused on the production of metabolites and their metabolic variations in U. dermestoides under stress conditions to provide additional valuable information to help better understand the broad-spectrum medical uses. To this end, VOCs were characterized by HS-SPME with PEG and CAR/PDMS fibers, and the first reported insect essential oils were obtained. In HS-SMPE, we found 17 terpenes, six quinones, five alkenes, and four aromatic compounds; in the essential oils, 53 terpenes, 54 carboxylic acids and derivatives, three alkynes, 12 alkenes (1-Pentadecene, EOT1: 77.6% and EOT2: 57.9%), 28 alkanes, nine alkyl disulfides, three aromatic compounds, 19 alcohols, three quinones, and 12 aldehydes were identified. Between both study approaches, a total of 171 secondary metabolites were identified with no previous report for U. dermestoides. A considerable number of the identified metabolites showed previous studies of the activity of pharmacological interest. Therefore, considering the wide variety of activities reported for these metabolites, this work allows a broader vision of the therapeutic potential of U. dermestoides in traditional medicine.


Assuntos
Besouros/química , Insetos/química , Óleos Voláteis/química , Álcoois/química , Aldeídos/química , Animais , Benzoquinonas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Terpenos/química , Compostos Orgânicos Voláteis/química
10.
Int J Mol Sci ; 22(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34502432

RESUMO

In the search for optimized thrombin binding aptamers (TBAs), we herein describe the synthesis of a library of TBA analogues obtained by end-functionalization with the electron-rich 1,5-dialkoxy naphthalene (DAN) and the electron-deficient 1,8,4,5-naphthalenetetra-carboxylic diimide (NDI) moieties. Indeed, when these G-rich oligonucleotides were folded into the peculiar TBA G-quadruplex (G4) structure, effective donor-acceptor charge transfer interactions between the DAN and NDI residues attached to the extremities of the sequence were induced, providing pseudo-cyclic structures. Alternatively, insertion of NDI groups at both extremities produced TBA analogues stabilized by π-π stacking interactions. All the doubly-modified TBAs were characterized by different biophysical techniques and compared with the analogues carrying only the DAN or NDI residue and unmodified TBA. These modified TBAs exhibited higher nuclease resistance, and their G4 structures were markedly stabilized, as evidenced by increased Tm values compared to TBA. These favorable properties were also associated with improved anticoagulant activity for one DAN/NDI-modified TBA, and for one NDI/NDI-modified TBA. Our results indicated that TBA pseudo-cyclic structuring by ad hoc designed end-functionalization represents an efficient approach to improve the aptamer features, while pre-organizing and stabilizing the G4 structure but allowing sufficient flexibility to the aptamer folding, which is necessary for optimal thrombin recognition.


Assuntos
Anticoagulantes/química , Aptâmeros de Nucleotídeos/química , Quadruplex G , Álcoois/química , Anticoagulantes/farmacologia , Avaliação Pré-Clínica de Medicamentos , Imidas/química , Naftalenos/química
11.
Biomed Res Int ; 2021: 5536030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395619

RESUMO

Argania spinosa (L.) plays an important role in the Moroccan agroeconomy, providing both employment and export revenue. Argan oil production generates different by-products with functionalities that are not yet investigated, in particular, the shell fruit. The present study aims, for the first time, at evaluating the acute and subacute toxicity, anti-inflammatory, and antioxidant effects of argan fruit shell ethanol extract (AFSEE). The LD50 of AFSEE was determined to be greater than the 5000 mg/kg body weight of mice. No significant variation in the body and organ weights was observed after 28 days of AFSEE treatment compared to that of the control group. Biochemical parameters and histopathological examination revealed no toxic effects of AFSEE. The AFSEE produced a significant inhibition of xylene-induced ear edema in mice. AFSEE reduced significantly the paw edema in mice after carrageenan injection. The chemical characterization showed that AFSEE contains a high level of total phenol content, flavonoids, condensed tannins, and flavanols. The obtained IC50 of DPPH, ABTS, reducing power, and ß-carotene demonstrates that AFSEE has a potential antioxidant effect. The results indicate that AFSEE was safe and nontoxic to mice even at higher doses. Furthermore, the present findings demonstrate that AFSEE has potential anti-inflammatory and antioxidant activities.


Assuntos
Álcoois/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Edema/tratamento farmacológico , Sapotaceae/química , Xilenos/toxicidade , Álcoois/química , Álcoois/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Dose Letal Mediana , Masculino , Camundongos , Marrocos , Extratos Vegetais/química
12.
J Am Chem Soc ; 143(28): 10565-10570, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34232661

RESUMO

Aerobic alcohol oxidations catalyzed by transition metal salts and aminoxyls are prominent examples of cooperative catalysis. Cu/aminoxyl catalysts have been studied previously and feature "integrated cooperativity", in which CuII and the aminoxyl participate together to mediate alcohol oxidation. Here we investigate a complementary Fe/aminoxyl catalyst system and provide evidence for "serial cooperativity", involving a redox cascade wherein the alcohol is oxidized by an in situ-generated oxoammonium species, which is directly detected in the catalytic reaction mixture by cyclic step chronoamperometry. The mechanistic difference between the Cu- and Fe-based catalysts arises from the use iron(III) nitrate, which initiates a NOx-based redox cycle for oxidation of aminoxyl/hydroxylamine to oxoammonium. The different mechanisms for the Cu- and Fe-based catalyst systems are manifested in different alcohol oxidation chemoselectivity and functional group compatibility.


Assuntos
Álcoois/química , Óxidos N-Cíclicos/química , Compostos Férricos/química , Nitratos/química , Compostos de Amônio Quaternário/síntese química , Catálise , Estrutura Molecular , Oxirredução , Compostos de Amônio Quaternário/química
13.
Org Lett ; 23(15): 5703-5708, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34296877

RESUMO

Enantioselective catalytic Giese addition of photogenerated α-alkoxy radicals to acyl pyrazolidinones can be accomplished using a tandem Sc(III) Lewis acid/photoredox catalyst system. Surprisingly, the excited-state oxidation potential was not the only important variable, and the optimal photocatalyst was not the strongest oxidant screened. Our results show that both the oxidation and reduction potentials of the photocatalyst can be important for the reaction outcome, highlighting the importance of holistic considerations in designing photochemical reactions.


Assuntos
Álcoois/química , Catálise , Ácidos de Lewis , Estrutura Molecular , Oxirredução , Processos Fotoquímicos , Estereoisomerismo
14.
Biomed Res Int ; 2021: 5577594, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235220

RESUMO

OBJECTIVE: Alzheimer's disease is a progressive, age-related, and neurodegenerative disease characterized by mental decline. The exact cause of Alzheimer's disease is unclear, but cholinergic dysfunction, protein accumulation, and oxidative stress are among the most important hypotheses. The main purpose of our study was to investigate the effects of aqueous and hydroalcoholic extract combination of these two medicinal plants, black pepper and cumin (as a related formulation in traditional Persian medicine), on memory and learning of an immobilized stress animal model. METHODS: In this study, hydroalcoholic and aqueous extracts of cumin and black pepper fruits were prepared. Six groups of mice were treated orally for 2 weeks: control group, immobility stress, and stress-induced immobility mice received different doses of the hydroalcoholic extract (100 and 200 mg/kg) and aqueous extract (100 and 200 mg/kg). The shuttle box, novel object detection, and rotarod test were used to evaluate memory and learning. The activities of acetylcholinesterase, catalase (CAT), and superoxide dismutase (SOD) and the level of reduced glutathione (GSH) and malondialdehyde (MDA) were measured in the brain tissue. RESULTS: Immobility stress significantly reduced learning and motor coordination. Furthermore, MDA levels and acetylcholinesterase activity were significantly increased, while CAT and SOD activities were significantly reduced in the brain of immobility-induced stress mice. Other findings indicated that hydroalcoholic and aqueous extracts (100 and 200 mg/kg) of cumin and black pepper fruits have an improving effect on animal motor coordination and learning ability, GSH content, and CAT, SOD, and acetylcholinesterase enzyme function in comparison with stress groups (p < 0.05). CONCLUSION: The hydroalcoholic and aqueous extracts of cumin and black pepper fruits have protective effects against stress-induced memory deficit and oxidative stress and may have beneficial therapeutic effect in the treatment of neurodegenerative diseases.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Apiaceae/metabolismo , Transtornos da Memória/tratamento farmacológico , Piper nigrum/metabolismo , Acetilcolinesterase/metabolismo , Álcoois/química , Animais , Aprendizagem da Esquiva , Capsicum/química , Catalase/metabolismo , Cuminum/química , Modelos Animais de Doenças , Glutationa/metabolismo , Imobilização , Irã (Geográfico) , Peroxidação de Lipídeos , Medicina Tradicional , Camundongos , Estresse Oxidativo , Extratos Vegetais/farmacologia , Estresse Mecânico , Estresse Psicológico , Superóxido Dismutase/metabolismo
15.
Int J Biol Macromol ; 183: 2227-2237, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34087307

RESUMO

Commercial pectin production is based on vacuum evaporation and alcohol precipitation (VEAP) using large quantities of expensive and flammable alcohol. This process has high production costs that have greatly limited the commercial use of refined pectins. This study demonstrates a new technology using a diaultrafiltration (DUF) process in a pilot plant, which is a low-cost, green, and ecologically friendly way to produce pectin. In terms of the structure and quality of their products, a comparison of the two methods suggest that DUF provides significant (p < 0.05) flux enhancement, high pectin purity, and separation of the main pectin backbones, with higher molar mass (Mw) and less polydispersity (Mw/Mn) of pectin samples. An analysis of the 1D and 2D NMR spectra reveals that the DUF process removes most free impurities extracted along with the pectin macromolecules, making this method preferable to use. An analysis of power and chemical consumption demonstrates that the new process is preferable over existing methods due to lower energy consumption and higher product quality. It also possesses a flexible technical design that allows it to produce semi-products from various raw materials.


Assuntos
Flores/química , Frutas/química , Química Verde , Helianthus/química , Malus/química , Pectinas/isolamento & purificação , Álcoois/química , Precipitação Química , Química Verde/instrumentação , Estrutura Molecular , Peso Molecular , Controle de Qualidade , Ultrafiltração , Vácuo , Resíduos
16.
J Chromatogr A ; 1649: 462223, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34038781

RESUMO

This work presents the investigation of two aliphatic polycarbonate diols (CAPC and HAPC) as the stationary phases for capillary gas chromatography (GC). The CAPC and HAPC capillary columns showed moderate polarity and high column efficiency of 3704 - 4545 plates/m measured by n-octanol and naphthalene at 120 °C. It was found that despite their similar chemical compositions, CAPC and HAPC differ largely in their selectivity towards the isomers of alkanes, methylpyridines and xylenes. As demonstrated, the CAPC column exhibits advantageous comprehensive performance over the HAPC column and the commercial PEG column. Particularly, the CAPC column exhibits higher resolving performance towards the isomers indicated above and the Grob mixture than the HAPC column. Also, it shows distinct advantages over the PEG column in separating the Grob mixture, the isomers of diethylbenzenes and cymenes, and practical analysis of chemical products and the essential oil from the leaves of Rhododendron dauricum L. Additionally, the CAPC column has excellent repeatability and reproducibility on analyte retention times with the relative standard deviation (RSD) values in the range of 0.05% - 0.08% for run-to-run, 0.12% - 0.19% for day-to-day and 2.6% - 4.9% for column-to-column, respectively. Its applications to purity test of chemical products and GC-MS analysis of the essential oil demonstrate its promising future for practical GC analyses.


Assuntos
Cromatografia Gasosa/métodos , Cimento de Policarboxilato/química , Álcoois/química , Alcanos/análise , Alcanos/química , Cimenos/análise , Cimenos/química , Isomerismo , Óleos de Plantas/análise , Reprodutibilidade dos Testes , Rhododendron/química
17.
Arch Pharm Res ; 44(5): 514-524, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33929687

RESUMO

Ginkgo biloba (Ginkgoaceae), commonly known as "ginkgo", is called a living fossil, and it has been cultivated early in human history for various uses in traditional medicine and as a source of food. As part of ongoing research to explore the chemical diversity and biologically active compounds from natural resources, two new coumaric acid-aliphatic alcohol hybrids, ginkwanghols A (1) and B (2) were isolated from the leaves of G. biloba. The coumaric acid-aliphatic alcohol hybrids of natural products have rarely been reported. The structures of the new compounds were determined by extensive NMR spectroscopic analysis, HRESI-MS, and quantum chemical ECD calculations, and by comparing the experimental HRESI-MS/MS spectrum of chemically transformed compound 1a with the predicted HRESI-MS/MS spectra proposed from CFM-ID 3.0, a software tool for MS/MS spectral prediction and MS-based compound identification. Ginkwanghols A (1) and B (2) increased alkaline phosphatase (ALP) production in C3H10T1/2, a mouse mesenchymal stem cell line, in a dose-dependent manner. In addition, ginkwanghols A and B mediated the promotion of osteogenic differentiation as indicated by the induction of the mRNA expression of the osteogenic markers ALP and osteopontin (OPN).


Assuntos
Álcoois/farmacologia , Ácidos Cumáricos/farmacologia , Ginkgo biloba/química , Folhas de Planta/química , Álcoois/química , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Ácidos Cumáricos/química , Camundongos , Estrutura Molecular , Osteogênese/efeitos dos fármacos
18.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466379

RESUMO

We evaluated a hydroalcoholic extract of Sapindus saponaria L. pericarps (ETHOSS), as a candidate to a topical antifungal medicine for onychomycosis. ETHOSS was produced by extracting the crushed fruits in ethanol. The saponin contents were identified and characterized by electrospray ionization mass spectrometry. We measured the in vitro antifungal activity against three dermatophyte fungi, isolated from onychomycosis: Trichophyton rubrum, T. mentagrophytes, and T. interdigitale, using broth microdilution tests. The minimum fungicide concentration of ETHOSS ranged from 195.31 to 781.25 µg/mL. The cytotoxicity of the crude extract was tested on the HeLa cell line, and its ability to permeate into healthy human nails by photoacoustic spectroscopy and Fourier transformation infrared spectrometer (FTIR) spectroscopy by attenuated total reflection. Besides its strong antifungal activity, ETHOSS showed low cytotoxicity in human cells. It was able to permeate and reach the full thickness of the nail in one hour, without the aid of facilitating vehicles, and remained there for at least 24 h. These results suggest that ETHOSS has great potential for treating onychomycosis.


Assuntos
Álcoois/química , Antifúngicos/farmacologia , Unhas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saponaria/química , Saponinas/farmacologia , Adulto , Feminino , Humanos , Unhas/metabolismo
19.
Molecules ; 26(1)2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401727

RESUMO

The performance of the previously optimized magnetic cross-linked enzyme aggregate of Eversa (Eversa-mCLEA) in the enzymatic synthesis of biolubricants by transesterification of waste cooking oil (WCO) with different alcohols has been evaluated. Eversa-mCLEA showed good activities using these alcohols, reaching a transesterification activity with isoamyl alcohol around 10-fold higher than with methanol. Yields of isoamyl fatty acid ester synthesis were similar using WCO or refined oil, confirming that this biocatalyst could be utilized to transform this residue into a valuable product. The effects of WCO/isoamyl alcohol molar ratio and enzyme load on the synthesis of biolubricant were also investigated. A maximum yield of around 90 wt.% was reached after 72 h of reaction using an enzyme load of 12 esterification units/g oil and a WCO/alcohol molar ratio of 1:6 in a solvent-free system. At the same conditions, the liquid Eversa yielded a maximum ester yield of only 34%. This study demonstrated the great changes in the enzyme properties that can be derived from a proper immobilization system. Moreover, it also shows the potential of WCO as a feedstock for the production of isoamyl fatty acid esters, which are potential candidates as biolubricants.


Assuntos
Enzimas Imobilizadas/química , Lubrificantes/química , Óleos/química , Resíduos , Álcoois/química , Catálise , Culinária , Enzimas Imobilizadas/metabolismo , Esterificação , Ésteres/química , Lipase/química , Lipase/metabolismo , Metanol/química , Pentanóis/química , Solventes , Óleo de Soja/química , Espectroscopia de Infravermelho com Transformada de Fourier
20.
PLoS One ; 15(12): e0242972, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33270707

RESUMO

Cola nitida known as Kola serves as flavouring ingredient in the food industry and is also of great importance during traditional rites in Africa. Despite the well-known pharmaceutical values of the species, efforts to develop improved varieties with enhanced nutraceutical quality is limited due to unavailability of information on variation of genotypes in bioactive compounds in the nuts. The objectives of this research were to evaluate 25 genotypes of kola for bioactive contents, determine relationship between nutritional and phenolic traits and to identify kola genotypes with good nutraceutical quality for use in developing improved varieties. The kola genotypes were established in the field using a randomized complete block design with three replicates. Nuts harvested from the blocks, were bulked and used to quantify soluble and insoluble sugars, total protein, moisture, ash, fats, pH, polyphenols, tannins and flavonoids using completely randomized design with three replicates in the laboratory. Data were analysed by combining Analysis of Variance, Kruskal-Wallis test, correlation test and multivariate analysis. Significant variations (P < 0.05) were observed among the kola genotypes for the bioactive traits evaluated. Phenolic traits were more heritable than nutritional traits. Although not significant (P > 0.05), correlation between nutritional and phenolic traits was negative, whereas correlations among nutritional traits were weak. On the contrary, significant and positive correlations (P < 0.05) were observed among phenolic traits. The hierarchical clustering analysis based on the traits evaluated grouped the 25 genotypes of kola evaluated into four clusters. Genotypes A12, JB4, JB19, JB36, P2-1b, and P2-1c were identified as potential parental lines for phenolic traits selection in kola whereas genotypes A10, Club, Atta1 and JB10 can be considered for soluble and insoluble sugar-rich variety development. These findings represent an important step towards improving nutritional and nutraceutical quality of kola nuts.


Assuntos
Cola/química , Cola/genética , Suplementos Nutricionais/análise , Variação Genética , Álcoois/química , Fenóis/análise , Solubilidade , Açúcares/química
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