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1.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204367

RESUMEN

The constitutive expression or overactivation of cyclooxygenase (COX) and lipoxygenase (LOX) enzymes results in aberrant metabolism of arachidonic acid and poor prognosis in melanoma. Our aim is to compare the in vitro effects of selective COX-1 (acetylsalicylic acid), COX-2 (meloxicam), 5-LOX (MK-886 and AA-861), 12-LOX (baicalein) and 15-LOX (PD-146176) inhibition in terms of proliferation (SRB assay), mitochondrial viability (MTT assay), caspase 3-7 activity (chemiluminescent assay), 2D antimigratory (scratch assay) and synthesis of eicosanoids (EIA) in the B16F10 cell line (single treatments). We also explore their combinatorial pharmacological space with dacarbazine and temozolomide (median effect method). Overall, our results with single treatments show a superior cytotoxic efficacy of selective LOX inhibitors over selective COX inhibitors against B16F10 cells. PD-146176 caused the strongest antiproliferation effect which was accompanied by cell cycle arrest in G1 phase and an >50-fold increase in caspases 3/7 activity. When the selected inhibitors are combined with the antineoplastic drugs, only meloxicam provides clear synergy, with LOX inhibitors mostly antagonizing. These apparent contradictions between single and combination treatments, together with some paradoxical effects observed in the biosynthesis of eicosanoids after FLAP inhibition in short term incubations, warrant further mechanistical in vitro and in vivo scrutiny.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/farmacología , Animales , Antineoplásicos/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Inhibidores de la Ciclooxigenasa/química , Dacarbazina/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inhibidores de la Lipooxigenasa/química , Melanoma Experimental , Ratones , Estructura Molecular , Temozolomida/farmacología
2.
J Sci Food Agric ; 100(3): 1092-1098, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31667839

RESUMEN

BACKGROUND: Plant-growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi have the ability to enhance the growth, fitness, and quality of various agricultural crops, including cowpea. However, field trials confirming the benefits of microbes in large-scale applications using economically viable and efficient inoculation methods are still scarce. Microbial seed coating has a great potential for large-scale agriculture through the application of reduced amounts of PGPR and AM fungi inocula. Thus, in this study, the impact of seed coating with PGPR, Pseudomonas libanensis TR1 and AM fungus, Rhizophagus irregularis (single or multiple isolates) on grain yield and nutrient content of cowpea under low-input field conditions was evaluated. RESULTS: Seed coating with P. libanensis + multiple isolates of R. irregularis (coatPMR) resulted in significant increases in shoot dry weight (76%), and in the number of pods and seeds per plant (52% and 56%, respectively) and grain yield (56%), when compared with non-inoculated control plants. However, seed coating with P. libanensis + R. irregularis single-isolate (coatPR) did not influence cowpea grain yield. Grain lipid content was significantly higher (25%) in coatPMR plants in comparison with control. Higher soil organic matter and lower pH were observed in the coatPMR treatment. CONCLUSIONS: Our findings indicate that cowpea field productivity can be improved by seed coating with PGPR and multiple AM fungal isolates under low-input agricultural systems. © 2019 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos/métodos , Glomeromycota/fisiología , Pseudomonas/fisiología , Semillas/microbiología , Vigna/crecimiento & desarrollo , Micorrizas/fisiología , Semillas/crecimiento & desarrollo , Suelo/química , Vigna/microbiología
3.
J Sci Food Agric ; 97(13): 4379-4385, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28071807

RESUMEN

BACKGROUND: Chickpea (Cicer arietinum L.) is a widely cropped pulse and an important source of proteins for humans. In Mediterranean regions it is predicted that drought will reduce soil moisture and become a major issue in agricultural practice. Nitrogen (N)-fixing bacteria and arbuscular mycorrhizal (AM) fungi have the potential to improve plant growth and drought tolerance. The aim of the study was to assess the effects of N-fixing bacteria and AM fungi on the growth, grain yield and protein content of chickpea under water deficit. RESULTS: Plants inoculated with Mesorhizobium mediterraneum or Rhizophagus irregularis without water deficit and inoculated with M. mediterraneum under moderate water deficit had significant increases in biomass. Inoculation with microbial symbionts brought no benefits to chickpea under severe water deficit. However, under moderate water deficit grain crude protein was increased by 13%, 17% and 22% in plants inoculated with M. mediterraneum, R. irregularis and M. mediterraneum + R. irregularis, respectively. CONCLUSION: Inoculation with N-fixing bacteria and AM fungi has the potential to benefit agricultural production of chickpea under water deficit conditions and to contribute to increased grain protein content. © 2017 Society of Chemical Industry.


Asunto(s)
Inoculantes Agrícolas/fisiología , Fenómenos Fisiológicos Bacterianos , Cicer/microbiología , Hongos/fisiología , Micorrizas/fisiología , Proteínas de Plantas/análisis , Agua/metabolismo , Bacterias/crecimiento & desarrollo , Cicer/química , Cicer/crecimiento & desarrollo , Cicer/metabolismo , Hongos/crecimiento & desarrollo , Nitrógeno/metabolismo , Proteínas de Plantas/metabolismo , Simbiosis , Agua/análisis
4.
J Toxicol Environ Health A ; 79(7): 329-37, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27077274

RESUMEN

The exploitation of arbuscular mycorrhizal (AM) fungi has become of great interest in agriculture due to their potential roles in reducing the need for agrochemicals, while improving plant growth and nutrition. Nevertheless, the application of AM fungi by dispersing inocula in granular form to open agricultural fields is not feasible because nontargeted spreading of inocula over large surface areas results in high cost per plant. Seed coating has the potential to significantly reduce the amount of inoculum needed, resulting in cost reduction and increased efficiency. The aim of this study was to assess whether seed coating with AM fungal inoculum is a feasible delivery system for production of common wheat (Triticum aestivum L.). Wheat seeds were coated with inoculum of Rhizophagus irregularis BEG140 and grown under different fertilization conditions: (1) none, (2) partial, or (3) complete. Data indicated that mycorrhizal inoculation via seed coating significantly increased the dry weight of shoot and seed spikes of wheat associated with reduced fertilization. Assessment of nutritional status of wheat showed that plants inoculated with R. irregularis via seed coating displayed enhanced stem concentrations of potassium (K), sulfur (S), and zinc (Zn). There were no significant differences in root colonization between plants conventionally inoculated with R. irregularis in soil and those inoculated via seed coating. Seed coating with AM fungi may be as effective as conventional soil inoculation and may contribute to reduce the utilization of chemical fertilizers. The application of AM via seed coating is proposed as an ecotechnological approach for sustainable agricultural wheat production.


Asunto(s)
Agricultura/métodos , Fertilizantes/análisis , Glomeromycota/fisiología , Micorrizas/fisiología , Microbiología del Suelo , Triticum/crecimiento & desarrollo , Semillas/microbiología , Semillas/fisiología , Triticum/microbiología
5.
J Toxicol Environ Health A ; 79(7): 320-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27077563

RESUMEN

The widespread use of agrochemicals is detrimental to the environment and may exert harmful effects on human health. The consumer demand for organic food plants has been increasing. There is thus a rising need for alternatives to agrochemicals that can foster sustainable plant production. The aim of this study was to evaluate the potential use of an arbuscular mycorrhizal (AM) fungus as an alternative to application of chemical fertilizer for improving growth performance of the medicinal and aromatic plant Coriandrum sativum. Plants were inoculated with the AM fungus Rhizophagus irregularis BEG163 and/or supplemented with a commercial chemical fertilizer (Plant Marvel, Nutriculture Bent Special) in agricultural soil. Plant growth, nutrition, and development of AM fungus were assessed. Plants inoculated with R. irregularis and those supplemented with chemical fertilizer displayed significantly improved growth performances when compared with controls. There were no significant differences in total fresh weight between plants inoculated with R. irregularis or those supplemented with chemical fertilizer. Leaf chlorophyll a + b (82%), shoot nitrogen (44%), phosphorus (254%), and potassium (27%) concentrations increased in plants inoculated with R. irregularis compared to controls. Application of chemical fertilizer inhibited root mycorrhizal colonization and the length of the extraradical mycelium of R. irregularis. Inoculation with R. irregularis was equally or more efficient than application of chemical fertilizer in promoting growth and nutrition of C. sativum. AM fungi may thus contribute to improve biologically based production of food plants and reduce the dependence on agrochemicals in agriculture.


Asunto(s)
Coriandrum/microbiología , Coriandrum/fisiología , Fertilizantes/análisis , Micorrizas/fisiología , Microbiología del Suelo , Coriandrum/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Plantas Medicinales/crecimiento & desarrollo , Plantas Medicinales/microbiología , Plantas Medicinales/fisiología
6.
J Toxicol Environ Health A ; 78(13-14): 931-44, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26167758

RESUMEN

A plant growth-promoting bacterial (PGPB) strain SC2b was isolated from the rhizosphere of Sedum plumbizincicola grown in lead (Pb)/zinc (Zn) mine soils and characterized as Bacillus sp. based on (1) morphological and biochemical characteristics and (2) partial 16S ribosomal DNA sequencing analysis. Strain SC2b exhibited high levels of resistance to cadmium (Cd) (300 mg/L), Zn (730 mg/L), and Pb (1400 mg/L). This strain also showed various plant growth-promoting (PGP) features such as utilization of 1-aminocyclopropane-1-carboxylate, solubilization of phosphate, and production of indole-3-acetic acid and siderophore. The strain mobilized high concentration of heavy metals from soils and exhibited different biosorption capacity toward the tested metal ions. Strain SC2b was further assessed for PGP activity by phytagar assay with a model plant Brassica napus. Inoculation of SC2b increased the biomass and vigor index of B. napus. Considering such potential, a pot experiment was conducted to assess the effects of inoculating the metal-resistant PGPB SC2b on growth and uptake of Cd, Zn and Pb by S. plumbizincicola in metal-contaminated agricultural soils. Inoculation with SC2b elevated the shoot and root biomass and leaf chlorophyll content of S. plumbizincicola. Similarly, plants inoculated with SC2b demonstrated markedly higher Cd and Zn accumulation in the root and shoot system, indicating that SC2b enhanced Cd and Zn uptake by S. plumbizincicola through metal mobilization or plant-microbial mediated changes in chemical or biological soil properties. Data demonstrated that the PGPB Bacillus sp. SC2b might serve as a future biofertilizer and an effective metal mobilizing bioinoculant for rhizoremediation of metal polluted soils.


Asunto(s)
Bacillus/metabolismo , Restauración y Remediación Ambiental/métodos , Sedum/crecimiento & desarrollo , Sedum/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Bacillus/aislamiento & purificación , Biodegradación Ambiental , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Metales Pesados/metabolismo , Datos de Secuencia Molecular , Filogenia , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Rizosfera , Sedum/microbiología , Análisis de Secuencia de ADN
7.
J Environ Manage ; 156: 62-9, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25796039

RESUMEN

Endophyte-assisted phytoremediation has recently been suggested as a successful approach for ecological restoration of metal contaminated soils, however little information is available on the influence of endophytic bacteria on the phytoextraction capacity of metal hyperaccumulating plants in multi-metal polluted soils. The aims of our study were to isolate and characterize metal-resistant and 1-aminocyclopropane-1-carboxylate (ACC) utilizing endophytic bacteria from tissues of the newly discovered Zn/Cd hyperaccumulator Sedum plumbizincicola and to examine if these endophytic bacterial strains could improve the efficiency of phytoextraction of multi-metal contaminated soils. Among a collection of 42 metal resistant bacterial strains isolated from the tissues of S. plumbizincicola grown on Pb/Zn mine tailings, five plant growth promoting endophytic bacterial strains (PGPE) were selected due to their ability to promote plant growth and to utilize ACC as the sole nitrogen source. The five isolates were identified as Bacillus pumilus E2S2, Bacillus sp. E1S2, Bacillus sp. E4S1, Achromobacter sp. E4L5 and Stenotrophomonas sp. E1L and subsequent testing revealed that they all exhibited traits associated with plant growth promotion, such as production of indole-3-acetic acid and siderophores and solubilization of phosphorus. These five strains showed high resistance to heavy metals (Cd, Zn and Pb) and various antibiotics. Further, inoculation of these ACC utilizing strains significantly increased the concentrations of water extractable Cd and Zn in soil. Moreover, a pot experiment was conducted to elucidate the effects of inoculating metal-resistant ACC utilizing strains on the growth of S. plumbizincicola and its uptake of Cd, Zn and Pb in multi-metal contaminated soils. Out of the five strains, B. pumilus E2S2 significantly increased root (146%) and shoot (17%) length, fresh (37%) and dry biomass (32%) of S. plumbizincicola as well as plant Cd uptake (43%), whereas Bacillus sp. E1S2 significantly enhanced the accumulation of Zn (18%) in plants compared with non-inoculated controls. The inoculated strains also showed high levels of colonization in rhizosphere and plant tissues. Results demonstrate the potential to improve phytoextraction of soils contaminated with multiple heavy metals by inoculating metal hyperaccumulating plants with their own selected functional endophytic bacterial strains.


Asunto(s)
Metales Pesados/metabolismo , Sedum/microbiología , Contaminantes del Suelo/farmacocinética , Bacillus/aislamiento & purificación , Bacillus/metabolismo , Biodegradación Ambiental , Biomasa , Cadmio/farmacocinética , Endófitos/metabolismo , Ácidos Indolacéticos/metabolismo , Metales Pesados/análisis , Metales Pesados/farmacología , Raíces de Plantas/microbiología , Rizosfera , Sedum/efectos de los fármacos , Sedum/metabolismo , Suelo , Contaminantes del Suelo/análisis , Zinc/farmacocinética
8.
J Phys Chem A ; 118(8): 1502-10, 2014 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-24517221

RESUMEN

The relationships among structural and thermodynamic properties of 2-, 3-, and 4-chlorobenzonitrile were investigated, in the present work, using several experimental techniques (Knudsen effusion, differential scanning calorimetry, and combustion calorimetry) and computational studies. The CN···Cl intermolecular interactions are weaker in 2-chlorobenzonitrile, reflecting a lower enthalpy of sublimation. The two polymorphic forms of 4-chlorobenzonitrile were observed by differential scanning calorimetry and interpreted in terms of the strength of CN···Cl intermolecular interactions. The entropic differentiation due to the pseudosymmetry observed in the crystalline packing of 2-chlorobenzonitrile was evaluated. Using adequate working reactions and the respective standard molar enthalpies of formation, in the gaseous phase, the halogen-cyano intramolecular interaction was also evaluated. The theoretically estimated gas-phase enthalpies of formation were calculated using high-level ab initio molecular orbital calculations at the G3MP2B3 and MP2/cc-pVTZ levels of theory. The computed values support very well the experimental results obtained in this work.

9.
J Phys Chem A ; 118(18): 3360-6, 2014 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-24741997

RESUMEN

4(3H)-Pyrimidinone is observed in nature in equilibrium with other tautomeric forms, mimicking the tautomeric equilibrium in pyrimidine nucleobases. In this work, the enthalpy of formation in the gaseous phase of 4(3H)-pyrimidinone was derived from the combination of the enthalpy of formation in the crystalline phase, obtained by static bomb combustion calorimetry, and the enthalpy of sublimation, obtained by Knudsen effusion. The gaseous phase enthalpy of formation of 4(3H)-pyrimidinone was interpreted in terms of isodesmic reactions that consider the enthalpic effects of hydroxypyridines and pyrimidine. After comparison of the experimental and computational results, the same type of isodesmic reactions was used to study the substituent effects of the hydroxyl functional group of 2-, 4-, and 5-hydroxypyrimidines. The influence of aromaticity on the energetics of hydroxypyrimidines was evaluated using the variation of nucleus-independent chemical shifts for several reactions. The influence of intramolecular hydrogen bonds was investigated using the quantum theory of atoms in molecules and the geometric rule of Baker and Hubbard to identify hydrogen bonds. The energetic results obtained were also interpreted in terms of an in plane anomeric effect in the pyrimidine ring.


Asunto(s)
Piridinas/química , Pirimidinas/química , Pirimidinonas/química , Calorimetría , Enlace de Hidrógeno , Termodinámica
10.
Animals (Basel) ; 14(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38998015

RESUMEN

Good zoo animal welfare is commonly promoted with environmental enrichment; however, some species are less likely to be offered enrichment than others. This study tested the effect of enrichment on a group of scarlet ibises from Zoomarine Algarve, Portugal. The study consisted of a first baseline condition, followed by four types of enrichment displays with individual presentations, a post-enrichment condition, and a post-enrichment with all enrichment types presented simultaneously. The enrichment types chosen were physical, with a tidal simulation in the lakes of the enclosure; nutritional, presenting mussels in a plastic mesh tube; sensory, by playing scarlet ibises calls; and tactile, with brushes through the habitat. The data collection was performed for 21 days between January and March 2021, 3 times a day, using scan sampling and instantaneous time sampling every 2 min. The comparison between conditions revealed that most behaviors showed similarity between the baseline and post-enrichment conditions, suggesting that after removing the enrichment, the behaviors returned to their initial baseline. It was also found that each enrichment influenced different types of behaviors and these behaviors also changed depending on the time of day. Exploratory behavior was only associated with the presence of enrichment, and vocalizations were only heard after the sensory enrichment was performed. This study demonstrates that the use of physical and tactile enrichments increased activity and decreased stationary behaviors in this group of ibises and may be used to improve their lives in zoological contexts if included in the housing and husbandry protocols.

11.
ChemSusChem ; 17(12): e202301801, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38323919

RESUMEN

The economic advantages of H2SO4 make it the acid of choice for the hydrometallurgical treatment of waste lithium-ion batteries (LIBs). However, to facilitate the full dissolution of the higher valency metal oxides present in the cathode black mass, a suitable reducing agent is required. Herein, the application of industrial black liquor (BL) obtained from the Kraft pulping for papermaking is investigated as a renewable reducing agent for the enhanced leaching of transition metals from LIB powder with H2SO4. The addition of acidified BL to H2SO4 significantly improved the leaching efficiency for a range of LIB cathode chemistries, with the strongest effect observed for manganese-rich active material. Focusing on NMC111 (LiMnxCoyNizO2) material, a linear correlation between the BL concentration and the leaching yield of Mn was obtained, with the best overall leaching efficiencies being achieved for 2.0 mol L-1 H2SO4 and 50 vol % of BL at 353 K. A quasi-total degradation of oxygenated and aromatic groups from the BL during NMC111 dissolution was observed after leaching, suggesting that these chemical groups are essential for LIB reduction. Finally, the leached transition metals could be easily recovered by pH adjustment and oxalic acid addition, closing the resource loop and fostering resource efficiency.

12.
J Phys Chem A ; 117(47): 12668-74, 2013 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-24205994

RESUMEN

In this work is investigated why the entrance of a nitrogen atom in the ring of cis-2-hydroxypyridine and 2-pyridinone, resulting in cis-4-hydroxypyrimidine and 4(3H)-pyrimidinone, respectively, shifts the tautomeric equilibrium from the hydroxyl form, in the pyridine derivative, to the ketonic form, in the pyrimidine derivative. The conclusions obtained for these model systems allow us to understand how to control the gaseous-phase keto-enol tautomeric equilibrium in nitrogen heterocyclic rings and justify the tautomeric preference in pyrimidine nucleobases. The experimental and computational energetics of tautomeric equilibrium were interpreted in terms of the aromaticity, intramolecular hydrogen bonds, and electronic delocalization, evaluated using nucleus independent chemical shifts, quantum theory of atoms in molecules, natural bond orbital analysis, and the thermodynamic changes of appropriate reactions.


Asunto(s)
Piridonas/química , Pirimidinonas/química , Teoría Cuántica , Enlace de Hidrógeno , Estructura Molecular , Termodinámica
13.
J Phys Chem A ; 117(28): 5826-36, 2013 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-23796002

RESUMEN

The enthalpy of hydrogenation of uracil was derived from the experimental enthalpies of formation, in the gaseous phase, of uracil and 5,6-dihydrouracil, in order to analyze its aromaticity. The enthalpy of formation of 5,6-dihydrouracil was obtained from combustion calorimetry, Knudsen effusion technique and Calvet microcalorimetry results. High-level computational methods were tested for the enthalpy of hydrogenation of uracil, but only with G3 was possible to obtain results in agreement with the experimental ones. It was found that uracil possesses 30.0% of aromatic character in the gaseous phase. Using both implicit, explicit, and hybrid solvation methods, it was possible to obtain a reference value for the enthalpy of hydrogenation of uracil in the aqueous solution and the effect of polarity and hydrogen bonds on the aromaticity of uracil was analyzed. The value of the hydrogenation enthalpy of uracil in aqueous solution was compared with the experimental value in the crystal phase, also dominated by polarity and hydrogen bonds, derived from combustion calorimetry results. The supramolecular effects on the crystal lattice were explored by the computational simulation of π-π staking dimers and hydrogen bonded dimers.


Asunto(s)
Termodinámica , Uracilo/química , Cristalización , Gases/química , Enlace de Hidrógeno , Hidrogenación , Estructura Molecular , Teoría Cuántica , Soluciones , Uracilo/análogos & derivados , Uracilo/síntesis química , Agua/química
14.
J Chromatogr A ; 1691: 463812, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36738573

RESUMEN

A study on the formation of ternary biphasic systems composed of heptane, 1-butanol or ethyl acetate and type III or type V deep eutectic solvents based on levulinic acid and choline chloride or thymol was carried. Binodal curves and densities and phase compositions of phases in equilibrium for seven systems are reported. The partition coefficients of six natural compounds, namely quercetin, apigenin, coumarin, ß-ionone, retinol, and α-tocopherol, in these systems were measured. Results show that the influence of choline chloride on the partition coefficients is more significant in systems with 1-butanol or ethyl acetate than previously reported for ethanol, and that the separation of natural compounds is worst when using DES containing thymol instead of choline chloride. Based on these partition coefficients, one system composed of heptane, 1-butanol and the DES choline chloride:levulinic acid at molar ratio 1:3 was selected to be applied in centrifugal partition chromatography, and the results obtained confirmed that it allows a good separation of apigenin, coumarin, ß-ionone and α-tocopherol.


Asunto(s)
Timol , alfa-Tocoferol , Solventes/química , 1-Butanol , Apigenina , Cromatografía Liquida/métodos , Cumarinas
15.
J Org Chem ; 77(9): 4312-22, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22409504

RESUMEN

The present work reports an energetic and structural study of 2-fluoro-, 3-fluoro-, and 4-fluorobenzonitrile. The standard molar enthalpies of formation, in the condensed phase, of the three isomers were derived from the standard molar energies of combustion, in oxygen, at T = 298.15 K. The standard molar enthalpies of vaporization or sublimation (for 4-fluorobenzonitrile), at T = 298.15 K, were measured using high-temperature Calvet microcalorimetry. The combination of these two parameters yields the standard molar enthalpies of formation in the gaseous phase. The vapor-pressure study of the referred compounds was performed by a static method, and the enthalpies of phase transition derived from the application of the Clarke and Glew equation. Theoretically estimated gas-phase enthalpies of formation, basicities, proton and electron affinities, and adiabatic ionization enthalpies were calculated from the G3MP2B3 level of theory. In order to evaluate the electronic properties, the geometries were reoptimized at MP2/cc-pVTZ level, and the QTAIM and NICS were computed. On the basis of the donor-acceptor system, another approach for evaluating the electronic effect for these compounds, using the NBO is suggested. The UV-vis spectroscopy study for the three isomers was performed. The intensities and the band positions were correlated with the thermodynamic properties calculated computationally.

16.
Nurs Times ; 108(39): 24-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23155905

RESUMEN

Complementary and alternative medicine is increasingly popular, and encompasses a number of systems and therapies based on diverse theories and practices, such as homoeopathy, traditional herbalism, reiki, ayurvedic medicine and traditional Chinese medicine. While many are based on metaphysical concepts for which there is no sound evidence, for herbal medicines there is a rational, scientific basis and increasing clinical evidence. This article suggests herbal medicines should no longer be considered part of CAM, but instead sit alongside conventional medicines.


Asunto(s)
Suplementos Dietéticos/normas , Enfermería Holística/métodos , Fitoterapia/métodos , Fitoterapia/normas , Humanos , Reino Unido
17.
ACS Sustain Chem Eng ; 10(15): 4913-4921, 2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-36570780

RESUMEN

In this work, centrifugal partition chromatography (CPC) assisted by a polyethylene glycol (PEG)/sodium polyacrylate (NaPA) aqueous biphasic system (ABS) was applied in the separation of five lignin-derived monomers (vanillin, vanillic acid, syringaldehyde, acetovanillone, and p-hydroxybenzaldehyde). The influence of the system pH (unbuffered, pH 5, and pH 12) and added electrolytes (inorganic salts or ionic liquids (ILs)) on the compound partition was initially evaluated. The obtained data revealed that ILs induced more adequate partition coefficients (K < 5) than inorganic salts (K > 5) to enable separation performance in CPC, while alkaline conditions (pH 12) demonstrated a positive impact on the partition of vanillic acid. CPC runs, with buffered ABS at pH 12, enabled a selective separation of vanillic acid from other lignin monomers. Under these conditions, a distinct interaction between the top (PEG-rich) and bottom (NaPA-rich) phases of the ABS with the double deprotonated form of vanillic acid is expected when compared to the remaining lignin monomers (single deprotonated). This is an impactful result that shows the pH to be a crucial factor in the separation of lignin monomer compounds by CPC, while only unbuffered systems have been previously studied in the literature. Finally, the recovery of vanillic acid up to 96% purity and further recycling of ABS phase-forming components were approached as a proof of concept through the combination of ultrafiltration and solid-phase extraction steps.

18.
Food Chem ; 372: 131214, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34619523

RESUMEN

Currently, the ability to produce several kinds of water-soluble red natural colorants makes the genus Talaromyces particularly important to the dye industry, which can be an alternative to the use of harmful synthetic colorants. In this study, colored compounds produced by Talaromyces amestolkiae were extracted, characterized chemically and the color stability of the fermented broth without any extraction procedure was further evaluated over pH variation. Five azaphilones compounds were detected by Ultrahigh Performance Liquid Chromatography-Mass Spectrometry system, all being complexes of the fatty acid amino-hexanedioic acid and azaphilone Monascus colorants. The color of the fermented broth was stable at a wide range of pH (3-9). Furthermore, T. amestolkiae colorants precipitated through hydrolysis of key chemical groups at extremely acidic (pH 1) and lose red color in extremely basic (pH 13) medium, showing negative halochromism. Nevertheless, these findings enhance the industrial relevance of azaphilone colorants produced by biotechnological process.


Asunto(s)
Monascus , Talaromyces , Benzopiranos , Pigmentos Biológicos , Talaromyces/genética
19.
3 Biotech ; 11(6): 293, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34136330

RESUMEN

Conventional agricultural practices based on the application of synthetic fertilizers are increasingly considered as unsustainable. Under a forecasted scenario of drought for the next decades, there is a global demand for innovative and sustainable approaches to ameliorate plant performance. Here, encapsulating beneficial microbes (BMs) to promote plant growth is gaining attention. This study evaluates bacterial encapsulation using polymeric beads of alginate, testing the survival of Pseudomonas libanensis TR1 stored up to 90 days. Produced beads were subjected to different treatments (fresh, air-dried and pulverized), which resulted in a variable size range (1200-860 µm). After storage, bacterial viability was maintained, and air-dried beads displayed a higher number of colony-forming units (2 × 107). Then, a glasshouse experiment investigated the drought resistance (plant growth, biomass, and photosynthetic responses) of Vigna unguiculata plants inoculated with these alginate beads. After 10 days of complete water restriction, turgidity and relative water content of V. unguiculata were still high under drought stress (> 80%). Leaf and root growth and biomass did not evidence significant changes after water restriction even after P. libanensis inoculation. Plant photosynthetic parameters (stomatal conductance, net photosynthetic rate, leaf CO2 concentration, or F v'/F m') were slightly affected due to inoculation but the level of stress-induced minimal plant responses. In our experiment, water restriction might have been insufficient to downregulate photosynthetic efficiency and reduce plant growth, limiting our understanding of the role of P. libanensis inoculation in alleviating drought stress in V. unguiculata, but highlighting the important relationship between the stress level and agricultural benefits of using encapsulated BMs.

20.
Rev Bras Enferm ; 74(6): e20210125, 2021.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-34320147

RESUMEN

OBJECTIVE: To evaluate the impact of implementing the SafeCare clinical supervision model on nurses' job satisfaction and emotional competence profile. METHODS: This is a quasi-experimental study, with a sample of 28 nurses from a hospital in northern Portugal. A self-administered questionnaire was applied, used as pre and post-test, which included: sociodemographic and professional characterization; "Job Satisfaction Scale"; and "Veiga Emotional Competence Scale". We conducted descriptive statistical analysis and the Wilcoxon Test. RESULTS: A significant decrease in the nurses' satisfaction with hierarchical superior was observed in the post-test. No significant differences were found in the nurses' job satisfaction and emotional competence after the implementation of the SafeCare Model. CONCLUSION: The SafeCare Model needs improvement, suggesting increasing the amount of training time administered to nurses and strengthening the healthcare institution's link to the Model.


Asunto(s)
Enfermeras y Enfermeros , Personal de Enfermería en Hospital , Actitud del Personal de Salud , Estudios Transversales , Humanos , Satisfacción en el Trabajo , Portugal , Encuestas y Cuestionarios
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