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1.
Physiol Plant ; 176(2): e14274, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566272

RESUMEN

AIMS: Phorbol esters (PE) are toxic diterpenoids accumulated in physic nut (Jatropha curcas L.) seed tissues. Their biosynthetic pathway remains unknown, and the participation of roots in this process may be possible. Thus, we set out to study the deposition pattern of PE and other terpenoids in roots and leaves of genotypes with detected (DPE) and not detected (NPE) phorbol esters based on previous studies. OUTLINE OF DATA RESOURCES: We analyzed physic nut leaf and root organic extracts using LC-HRMS. By an untargeted metabolomics approach, it was possible to annotate 496 and 146 metabolites in the positive and negative electrospray ionization modes, respectively. KEY RESULTS: PE were detected only in samples of the DPE genotype. Remarkably, PE were found in both leaves and roots, making this study the first report of PE in J. curcas roots. Furthermore, untargeted metabolomic analysis revealed that diterpenoids and apocarotenoids are preferentially accumulated in the DPE genotype in comparison with NPE, which may be linked to the divergence between the genotypes concerning PE biosynthesis, since sesquiterpenoids showed greater abundance in the NPE. UTILITY OF THE RESOURCE: The LC-HRMS files, publicly available in the MassIVE database (identifier MSV000092920), are valuable as they expand our understanding of PE biosynthesis, which can assist in the development of molecular strategies to reduce PE levels in toxic genotypes, making possible the food use of the seedcake, as well as its potential to contain high-quality spectral information about several other metabolites that may possess biological activity.


Asunto(s)
Jatropha , Jatropha/genética , Jatropha/metabolismo , Ésteres del Forbol/análisis , Ésteres del Forbol/metabolismo , Hojas de la Planta/metabolismo , Semillas/genética
2.
ACS Omega ; 9(7): 7424-7438, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38405509

RESUMEN

In this study, we report the synthesis of a new compound, N4,N4-dimethyl-2-(methylsulfanyl)-N6-(4-phenoxyphenyl)pyrimidine-4,6-diamine (DMS), and its comprehensive analysis through structural and spectroscopic characterizations, reactivity parameters, and nonlinear optical properties, utilizing a combination of experimental and computational techniques. The experimental aspect of the investigation encompassed structural characterization using X-ray diffraction and spectroscopic assessments employing Fourier-transform infrared, Raman, and nuclear magnetic resonance techniques, along with thermal analysis. Our computational approach involved density functional theory (DFT) calculations and molecular dynamics (MD) simulations to examine the local reactivity properties of DMS. We employed fundamental reactivity descriptors to evaluate DMS's local reactivity and utilized MD simulations to identify DMS atoms engaging in significant interactions with water molecules. We conducted periodic DFT calculations on DMS's crystal structure to investigate the contributions of specific atoms and groups to the compound's overall stability as well as to analyze noncovalent interactions between DMS molecules. We assessed the nonlinear optical properties through dynamic second hyperpolarizability and third-order nonlinear susceptibility calculations. Additionally, we conducted a comparative analysis of the static and dynamic second hyperpolarizability for the DMS molecule within the sum-over-states framework. The obtained value for the third-order nonlinear susceptibility, (λ = 1907 nm), exceeds those of other organic materials reported in previous studies, indicating that the DMS crystal holds promise as a nonlinear optical material for potential application in photonic device fabrication. Furthermore, molecular docking studies were performed with the 3E5A, 4EUT, and 4EUU proteins, yielding binding affinities of -8.1, -8.2, and -8.3 kcal/mol, respectively, in association with the ligand.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123093, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37418906

RESUMEN

In recent years, scientists have been very interested in single crystals of monoaromatic compounds with mechanical softness, but they are hard to find. The present work reports a comparative study of structural, spectroscopic, and quantum chemical investigations of three structurally similar mechanically bending monoaromatic compounds, namely, 2-amino-3-nitro-5-chloro pyridine (I), 2-amino-3-nitro-5-bromo pyridine (II), and 2-amino-3-nitro-5-iodo pyridine (III). The mechanical responses of the three organic crystals studied here are very intriguing due to the similarity of their chemical structures, which only differ in the presence of halogen atoms (Cl, Br, and I) at the fifth position of the pyridine ring and are explained through examining intermolecular interaction energies from energy frameworks analysis, slip layer topology, and Hirshfeld surface analysis. The crystals of all the three feature one dimensional ribbons comprising alternating NaminoH⋯Onitro and NaminoH⋯Npyridine hydrogen bonds that form R22(12) and R22(8) dimeric rings, respectively. In (III), weak I⋯I interactions link the adjacent ribbons forming a two dimensional sheet. Layer-like structures are observed in all three crystals, with no significant interactions between the adjacent architectures (ribbons or sheets). Energy framework calculations are used for estimating the bending ability of the three compounds, with the three following the order Cl ≪ Br < I. The iterative electrostatic scheme coupled with the supermolecule approach (SM) at the DFT/CAM-B3LYP/aug-cc-pVTZ level is used to calculate the third-order nonlinear susceptibility (χ3) values in a simulated crystalline environment for the static case as well as two typical electric field frequency values, (λ = 1064 nm) and (λ = 532 nm). In addition, estimates of the topological studies (localized orbital locator and electron localization function) and reactivity characteristics (global reactivity parameters, molecular electrostatic potential, and Fukui function) are made for the compounds under investigation. Docking studies done using AutoDock software with a protein target (PDB ID: 6CM4) revealed that three compounds could be used to treat Alzheimer's disease.

4.
Sci Rep ; 13(1): 8616, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37244899

RESUMEN

The linear polarizability, first and second hyperpolarizabilities of the asymmetric unit of DAPSH crystal are studied and compared with available experimental results. The polarization effects are included using an iterative polarization procedure, which ensures the convergence of the dipole moment of DAPSH embedded within a polarization field generated by the surrounding asymmetric units whose atomic sites are considered as point charges. We estimate macroscopic susceptibilities from the results of the polarized asymmetric units in the unit cell, considering the significant contribution of the electrostatic interactions in crystal packing. The results show that the influence of the polarization effects leads to a marked decrease of the first hyperpolarizability, compared with the respective isolated counterpart, which improves the concordance with the experiment. There is a minor influence of polarization effects on the second hyperpolarizability but our estimated result for the third-order susceptibility, related to the NLO process of the intensity dependent refractive index, is significant as compared with the results for other organic crystals, such as chalcone-derivatives. In addition, supermolecule calculations are conducted for explicit dimers in presence of the electrostatic embedding to illustrate the role played by the electrostatic interactions in the hyperpolarizabilities of the DAPSH crystal.

5.
Naunyn Schmiedebergs Arch Pharmacol ; 396(8): 1773-1786, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36843129

RESUMEN

Acrolein is the main toxic metabolite of ifosfamide (IFO) that causes urothelial damage by oxidative stress and inflammation. Here, we investigate the molecular mechanism of action of gingerols, Zingiber officinale bioactive molecules, as an alternative treatment for ifosfamide-induced hemorrhagic cystitis. Female Swiss mice were randomly divided into 5 groups: control; IFO; IFO + Mesna; and IFO + [8]- or [10]-gingerol. Mesna (80 mg/kg, i.p.) was given 5 min before, 4 and 8 h after IFO (400mg/kg, i.p.). Gingerols (25 mg/kg, p.o.) were given 1 h before and 4 and 8 h after IFO. Animals were euthanized 12 h after IFO injection. Bladders were submitted to macroscopic and histological evaluation. Oxidative stress and inflammation were assessed by malondialdehyde (MDA) or myeloperoxidase assays, respectively. mRNA gene expression was performed to evaluate mesna and gingerols mechanisms of action. Mesna was able to protect bladder tissue by activating NF-κB and NrF2 pathways. However, we demonstrated that gingerols acted as an antioxidant and anti-inflammatory agent stimulating the expression of IL-10, which intracellularly activates JAK/STAT/FOXO signaling pathway.


Asunto(s)
Cistitis , Ifosfamida , Ratones , Animales , Femenino , Ifosfamida/toxicidad , Mesna/efectos adversos , Interleucina-10 , Cistitis/inducido químicamente , Cistitis/tratamiento farmacológico , Cistitis/patología , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Inflamación , Transducción de Señal
6.
Proteomics ; 23(1): e2200251, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35861729

RESUMEN

Açaí palm (Euterpe oleracea Mart.) seeds are a rich source of mannans, which can be used to generate bioethanol or be converted to high-value D-mannose, in addition to being a source of polyphenols with beneficial health properties. Here, we present a quantitative proteome dataset of açaí seeds at four stages of development (S1, S2, S3, and S4 stages), in which 2465 high confidence proteins were identified and 524 of them show statistically different abundance profiles during development. Several enzymes involved in the biosynthesis of nucleotide-sugars were quantified, especially those dedicated to the formation of GDP-mannose, which showed an increase in abundance between stages S1 and S3. Our data suggest that linear mannans found abundantly in endosperm cell walls are initially deposited as galactomannans, and during development lose the galactosyl groups. Two isoforms of alpha-galactosidase enzymes showed significantly increased abundances in the S3 and S4 stages. Additionally, we quantified the enzymes participating in the central pathway of flavonoid biosynthesis responsible for the formation of catechin and epicatechin, which are subunits of procyanidins, the main class of polyphenols in the açaí seeds. These proteins showed the same pattern of deposition, in which higher abundances were seen in the S1 and S2 stages.


Asunto(s)
Euterpe , Mananos , Antioxidantes , Proteómica , Semillas/química , Polifenoles/análisis , Extractos Vegetales
7.
Molecules ; 27(8)2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35458577

RESUMEN

A novel 4(1H) quinolinone derivative (QBCP) was synthesized and characterized with single crystal X-ray diffraction. Hirshfeld surfaces (HS) analyses were employed as a complementary tool to evaluate the crystal intermolecular interactions. The molecular global reactivity parameters of QBCP were studied using HOMO and LUMO energies. In addition, the molecular electrostatic potential (MEP) and the UV-Vis absorption and emission spectra were obtained and analyzed. The supermolecule (SM) approach was employed to build a bulk with 474,552 atoms to simulate the crystalline environment polarization effect on the asymmetric unit of the compound. The nonlinear optical properties were investigated using the density functional method (DFT/CAM-B3LYP) with the Pople's 6-311++G(d,p) basis set. The quantum DFT results of the linear polarizability, the average second-order hyperpolarizability and the third-order nonlinear susceptibility values were computed and analyzed. The results showed that the organic compound (QBCP) has great potential for application as a third-order nonlinear optical material.


Asunto(s)
Teoría Cuántica , Cristalografía por Rayos X , Modelos Moleculares , Conformación Molecular , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática
8.
Front Plant Sci ; 13: 843764, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371174

RESUMEN

Jatropha curcas L. is a non-edible oilseed containing almost 40% of seed oil and is famous as the best source of raw material for biofuel production. J. curcas seeds contain three main tissues, such as inner integument, endosperm, and embryo. To best understand the physiological events related to specific tissues, it is important to perform the proteome analysis of these tissues. Previously we have explored the pattern of reserves deposition and tissue-specific biological pathways by analyzing the proteome of the inner integument and endosperm and organelles, such as plastids and gerontoplasts isolated from these tissues. The focus of the present study was to perform the proteomic analysis of embryo isolated from the mature seeds of J. curcas. This analysis resulted in the identification of 564 proteins of which 206 are not identified previously from any other tissue of this plant. The identified proteins were functionally classified using the MapMan classification system revealing various proteins involved in different functionalities. The proteins involved in transport functions and those with proteolytic activity were determined through the Transporter Classification Database (TCDB) and MEROPS database, respectively. In addition to identify a large number of proteins participating in various metabolic processes, we found several proteins involved in defense functions, such as the members of chaperones and the ubiquitin-proteasome system. Similarly, members of the legumin and vicilin family of seed storage proteins (SSPs) were identified which in addition to their storage function, are involved in defense. In addition, we have reported that proteases belonging to different mechanistic classes and are involved in diverse physiological functions. Last but not the least, several classes of transport-related proteins were identified that are discussed concerning their function in the transportation of different nutrients across the embryo. To the best of our knowledge, this study reported the highest number of proteins identified from the embryo of mature J. curcas seeds, most of which are essential for seed germination, reflecting the fact that many proteins required for germination are already present in the mature embryo.

10.
Int J Biol Macromol ; 198: 77-86, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34963626

RESUMEN

This study aimed to partially characterize the three main serine carboxypeptidases (SCP3, SCP20, and SCP47) from Nepenthes mirabilis. Furthermore, one peptidase (SCP3) was chosen for further heterologous expression in Escherichia coli Shuffle®T7. SCP3 also was characterized in terms of its allergenic potential using bioinformatics tools. SCP3, SCP20, and SCP47 showed very similar 3D structures and mechanistic features to other plant serine peptidases belonging to clan SC and family S10. Although SCP3 was obtained in its soluble form, using 1% ethanol during induction with 0.5 mM IPTG at 16 °C for 18 h, it did not show proteolytic activity by zymography or in vitro analysis. SCP3 presented a few allergenic peptides and several cleavage sites for digestive enzymes. This work describes additional features of these enzymes, opening new perspectives for further studies for characterization and analysis of heterologous expression, as well as their potential biotechnological applications.


Asunto(s)
Carboxipeptidasas
11.
Phys Chem Chem Phys ; 23(10): 6128-6140, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33684185

RESUMEN

In this study, a combined experimental and theoretical study of the nonlinear optical properties (NLO) of two chalcone derivatives, (E)-3-(2-methoxyphenyl)-1-(2-(phenylsulfonylamine)phenyl)prop-2-en-1-one (MPSP) and (E)-3-(3-nitrophenyl)-1-(2-(phenylsulfonylamine)phenyl)prop-2-en-1-one (NPSP), in DMSO is reported. The single crystal structures of the compounds, which differ only by the type and position of one substituent, were grown using the slow evaporation technique, and the main structural differences are discussed. The two-photon absorption and first-order hyperpolarizability measurements were performed via the Z-scan technique and hyper-Rayleigh scattering experiment in DMSO. The theoretical calculations were performed using the Density Functional Theory (DFT) at the CAM-B3LYP/6-311++G(d,p) level, and the sum-over-states (SOS) approach in both static and dynamic cases. Besides the electron conjugation achieved by the aromatic rings, olefins, and carbonyl groups, both compounds have a nearly flat chalcone backbone, which is believed to contribute to the nonlinear optical properties. MPSP and NPSP have different positions, even though they have roughly the same conformation and form C-HO interactions. For several studied frequencies, the HRS first hyperpolarizability values for MPSP are greater than those for NPSP, indicating that in most cases the NLO properties of MPSP are better. The comparison among the theoretical and experimental HRS first hyperpolarizability results showed a good agreement. In addition, the two-dimensional second order nonlinear optical spectra obtained from the sum-over-states model indicate good second-order NLO responses of the two chalcone derivatives under external fields. Our findings are important not only to show the potential nonlinear optical application of the two new compounds but also to gain an insight into how different chemical compositions might affect the crystal structures and physico-chemical properties.

12.
J Nutr ; 151(1): 170-178, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-32939530

RESUMEN

BACKGROUND: Few studies have focused on quantitatively analyzing nutrients from infant diets, compromising complementary feeding evaluation and health promotion worldwide. OBJECTIVES: This study aimed to describe dietary intake in infants from 9 to 24 mo of age, determining nutrient intakes associated with the risk of underweight, wasting, and stunting. METHODS: Usual nutrient intakes from complementary feeding were determined by 24-h recalls collected when infants were 9-24 mo of age in communities from 7 low- and middle-income countries: Brazil (n = 169), Peru (n = 199), South Africa (n = 221), Tanzania (n = 210), Bangladesh (n = 208), India (n = 227), and Nepal (n = 229), totaling 1463 children and 22,282 food recalls. Intakes were corrected for within- and between-person variance and energy intake. Multivariable regression models were constructed to determine nutrient intakes associated with the development of underweight, wasting, and stunting at 12, 18, and 24 mo of age. RESULTS: Children with malnutrition presented significantly lower intakes of energy and zinc at 12, 18, and 24 mo of age, ranging from -16.4% to -25.9% for energy and -2.3% to -48.8% for zinc. Higher energy intakes decreased the risk of underweight at 12 [adjusted odds ratio (AOR): 0.90; 95% CI: 0.84, 0.96] and 24 mo (AOR: 0.91; 95% CI: 0.86, 0.96), and wasting at 18 (AOR: 0.91; 95% CI: 0.83, 0.99) and 24 mo (AOR: 0.83; 95% CI: 0.74, 0.92). Higher zinc intakes decreased the risk of underweight (AOR: 0.12; 95% CI: 0.03, 0.55) and wasting (AOR: 0.19; 95% CI: 0.04, 0.92) at 12 mo, and wasting (AOR: 0.05; 95% CI: 0.00, 0.76) at 24 mo. CONCLUSIONS: Higher intakes of energy and zinc in complementary feeding were associated with decreased risk of undernutrition in the studied children. Data suggest these are characteristics to be improved in children's complementary feeding across countries.


Asunto(s)
Ingestión de Energía , Trastornos de la Nutrición del Lactante/prevención & control , Fenómenos Fisiológicos Nutricionales del Lactante , Desnutrición , Estado Nutricional , Zinc/administración & dosificación , África/epidemiología , Asia/epidemiología , Países en Desarrollo , Dieta , Femenino , Análisis de los Alimentos , Humanos , Lactante , Modelos Logísticos , Masculino , Necesidades Nutricionales , América del Sur/epidemiología , Delgadez
14.
Plant Sci ; 298: 110569, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32771170

RESUMEN

The role of the cotyledonary haustorium (CH) in the mobilization of nutrient reserves in the endosperm of species of the palm family Arecaceae is a moot question. To shed light on this matter, we present here an analysis of the quantitative proteome changes associated with four developmental stages of CH and three of endosperm during germination. Together, a total of 1965 proteins were identified, being 1538 in the CH and 960 in the endosperm. Both in the CH and endosperm proteomes, we observed an increase in the diversity of hydrolases as the CH and endosperm develops. Qualitative proteomics analysis of four CH developmental stages indicated that each stage is populated by a unique set of proteins and the quantitative analysis showed an increase in the relative abundance of hydrolases, particularly mannan degrading enzymes, as development progresses. These results add weight to the hypothesis that the CH in the seeds of E. oleraceaacts both as a conduit of carbon and nitrogen sources generated by the hydrolysis of the reserves in the endosperm and as a source of hydrolases that will contribute to the mobilization of these reserves.


Asunto(s)
Euterpe/fisiología , Germinación/genética , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Semillas/crecimiento & desarrollo , Cotiledón/metabolismo , Endospermo/metabolismo
15.
Proteomics ; 20(14): e1900273, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32419338

RESUMEN

The phorbol esters in the seeds of Jatropha curcas are a major hindrance to the full exploitation of the potential of this oil crop as a source of raw material for the production of biodiesel. Here, various quantitative proteomic strategies are used to establish the proteomes of roots, leaves, and endosperm of two genotypes of J. curcas with contrasting levels of phorbol esters in the seeds. In total 4532, 1775, and 503 proteins are identified respectively in roots, leaves, and endosperm, comprising 5068 unique proteins; of this total, 185 are differentially abundant in roots, 72 in leaves, and 20 in the endosperm. The biosynthetic pathways for flavonoids and terpenoids are well represented in roots, including the complete set of proteins for the mevalonate and non-mevalonate/Deoxyxylulose 5-Phosphate pathways, and proteins involved in the branches which lead to the synthesis tricyclic diterpenoids and gibberellins. Also, casbene synthase which catalyzes the first committed step in the biosynthesis of tigliane-type diterpenes is identified in roots of both genotypes, but not in leaves and endosperm. This dataset will be a valuable resource to explore the biochemical basis of the low toxicity of Jatropha genotypes with low concentration of phorbol esters in the seeds.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Jatropha/metabolismo , Ésteres del Forbol/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/análisis , Proteoma/metabolismo , Semillas/metabolismo , Genotipo , Jatropha/crecimiento & desarrollo , Semillas/crecimiento & desarrollo
16.
Rev. colomb. quím. (Bogotá) ; 49(1): 33-39, Jan.-Apr. 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1098957

RESUMEN

Abstract The use of organic as nonlinear optical materials has been intensively explored in the recent years due to the ease of manipulation of the molecular structure and the synthetic flexibility regarding the change of substituent groups. In the present work, the linear and nonlinear properties of two chalcones derivatives (E)-1-(4-methylphenyl)-3-phenylprop-2-en-1-one (4MP3P) and (E)-1-(4-Nitrophenyl)-3-phenylprop-2-en-1-one (4NP3P), that differ by the substituent position at the phenyl ring, were studied in the presence of protic and aprotic solvents simulated by the Polarizable Continuum Model (PCM) at DFT/B3LYP/6-311+G(d) level. The static and dynamic (1064 nm) molecular parameters as the dipole moment, linear polarizability, first and second hyperpolarizabilities were studied as function of the solvent dielectric constant value. The geometrical behavior as the chemical bond angles, torsion angles, and partial charges distribution of the compounds were studied, including calculations of gap energies in various solvents. The obtained results revealed that the substituent change of CH3 (4MP3P) to NO2 (4NP3P) benefits the nonlinear optical properties of the compounds in the presence of the solvent media, the absolute values of the parallel first hyperpolarizability were the ones that present the greater variation.


Resumen El uso de materiales orgánicos como materiales ópticos no lineales se ha explorado intensamente en los últimos años, debido a la facilidad de manipulación de estas estructuras moleculares y la flexibilidad de síntesis en relación con el cambio de grupos sustituyentes. En el presente trabajo, las propiedades lineales y no lineales de dos derivados de chalcona (E)-1-(4-metilfenil)-3-fenilprop-2-en-1-ona (4MP3P) y (E)-1-(4-nitrofenil)-3-fenilprop-2-en-1-ona (4NP3P), los cuales difieren en la posición del sustituyente en el anillo de fenilo, se estudiaron en presencia de disolventes próticos y apróticos simulados por el Modelo Continuo Polarizable a nivel DFT/B3LYP/6-311+G(d). Además, se estudiaron parámetros moleculares estáticos y dinámicos (1064 nm) como el momento dipolar, la polarización lineal y la primera y la segunda hiperpolarización en función del valor constante dieléctrico del disolvente. El comportamiento geométrico se estudió como ángulos de enlace químico, ángulos de torsión y distribución de carga parcial de compuestos, incluidos los cálculos de energía de huecos en varios solventes. Los resultados mostraron que el cambio del sustituyente CH3 (4MP3P) a NO2 (4NP3P) beneficia las propiedades ópticas no lineales de los compuestos en presencia del medio solvente, los valores absolutos de la primera hiperpolarizabilidad paralela fueron los que presentaron la mayor variación.


Resumo O uso de materiais orgânicos como materiais ópticos não lineares tem sido intensamente explorado nos últimos anos, devido à facilidade de manipulação dessas estruturas moleculares e à flexibilidade de síntese em relação à mudança de grupos substituintes. No presente trabalho, as propriedades lineares e não lineares de dois derivados de chalconas (E)-1-(4-metilfenil)-3-fenilprop-2-en-1-ona (4MP3P) e (E)-1-(4-nitrofenil)-3-fenilprop-2-en-1-ona (4NP3P), que diferem pela posição do substituinte no anel fenil, foram estudados na presença de solventes próticos e apróticos simulados pelo Modelo Continuo Polarizável (PCM) no nível DFT/B3LYP/6-311+G(d). Os parâmetros moleculares estáticos e dinâmicos (1064 nm) como momento dipolar, polarizabilidade linear, primeira e segunda hiperpolarizabilidades foram estudados em função do valor da constante dielétrica do solvente. Estudou-se o comportamento geométrico como ângulos de ligação química, ângulos de torção e distribuição parcial de cargas dos compostos, incluindo cálculos de energias de gap em vários solventes. Os resultados obtidos revelaram que a mudança do substituinte de CH3 (4MP3P) para NO2 (4NP3P) beneficia as propriedades ópticas não lineares dos compostos na presença do meio solvente, os valores absolutos da primeira hiperpolarizabilidade paralela foram os que apresentaram a maior variação.

17.
J Proteome Res ; 19(1): 437-445, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31814414

RESUMEN

Quantitative proteome analysis of four developmental stages of pericarp tissues of the açaí berry (Euterpe oleracea Mart.) was performed by the isobaric labeling of peptides with iTRAQ 4-plex, hydrophilic interaction liquid chromatography pre-fractionation of labeled peptides, and high-performance mass spectrometry analysis. This analysis resulted in the identification of 4286 proteins, of which 476 presented differential abundance between the stages. The differential abundance of these proteins was seen to be coordinated with the metabolic demands during cell division, lignification, and cell expansion at developmental stages 1 and 2 as well as phenolic acid accumulation and metabolic changes in the fruit maturation at developmental stages 3 and 4. The distinct accumulation of anthocyanins observed in the pericarp at developmental stage 4 was correlated with the increase in abundance of some key biosynthetic enzymes, such as leucoanthocyanidin dioxygenase, anthocyanidin O-3-glycosyltransferase, and UDP-glycosyltransferase. Here, evidence is also provided for the presence in the açaí berry of secondary metabolites not previously described in açaí, such as pterostilbene, matairesinol, and furaneol. Together, these results will pave the way for studies aimed at the genetic improvement of the nutritional properties of this important fruit crop.


Asunto(s)
Euterpe/crecimiento & desarrollo , Euterpe/metabolismo , Frutas/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Aminoácidos/biosíntesis , Aminoácidos/metabolismo , Antocianinas/análisis , Antocianinas/metabolismo , Metabolismo de los Hidratos de Carbono , Enzimas/metabolismo , Frutas/metabolismo , Espectrometría de Masas , Proteínas de Plantas/análisis , Proteómica/métodos , Metabolismo Secundario
18.
J Mol Model ; 25(11): 324, 2019 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-31654205

RESUMEN

In this work, the nonlinear optical (NLO) properties of two heterocyclic chalcones, (E)-1-(5-chlorothiophen-2-yl)-3-(thiophen-2yl)-2-propen-1-one (CLTT) and (E)-1-(5-methylfuran-2-yl)-3-(5-methylthiophen-2-yl)prop-2en-1-one (2MFT), are investigated. Using an iterative electrostatic embedding approach via the Møller-Plesset perturbation (MP2) theory, the chalcone crystals were simulated and the polarization effects on the isolated molecules are investigated. The electrical parameters of CLTT and 2MFT as dipole moment and linear polarizability were calculated via MP2/6-311++G(d) and the second hyperpolarizability was obtained via DFT/CAM-B3-LYP/6-311++G(d) level. A significant influence of the molecular packing on the chalcone electric parameters was observed. The static linear refractive index and the third-order electric susceptibility of the compounds were calculated and compared with experimental results available for other chalcone derivatives, indicating the CLTT crystal as a promising candidate for NLO applications in photonic and optoelectronic devices. The Hirshfeld surface analysis has been used to quantify the intermolecular interactions of the molecular crystals. Additionally, the solvent medium effects on the electrical properties of the heterocyclic chalcones were also studied.

19.
J Phys Chem A ; 123(40): 8632-8643, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31525043

RESUMEN

The application of organic crystals on nonlinear optical (NLO) materials has been increasing in recent years, and compounds like chalcones are interesting due to their significant third-order nonlinear properties. Hereof, we describe the synthesis, molecular structure, supramolecular arrangement, and theoretical calculations for a bromine-chalcone 3-(4-bromophenyl)-1-[3-(2-oxo-2-phenylethoxy)phenyl]-propenone (BC), which crystallized into noncentrosymmetric space group Pc. Also, a comprehensive topological analysis performed by QTAIM highlights the observed halogen bonds on solid state. In addition, the thermal stability was studied in temperatures smaller than 800 °C showing BC crystal as potential optical devices at temperatures up to 250 °C. Finally, the NLO properties indicate a photonic application based on strong third-order nonlinear response.

20.
PLoS Negl Trop Dis ; 13(2): e0007154, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30735493

RESUMEN

BACKGROUND: Diarrheal diseases are an important cause of morbidity and mortality among children in developing countries. We aimed to study the etiology and severity of diarrhea in children living in the low-income semiarid region of Brazil. METHODOLOGY: This is a cross-sectional, age-matched case-control study of diarrhea in children aged 2-36 months from six cities in Brazil's semiarid region. Clinical, epidemiological, and anthropometric data were matched with fecal samples collected for the identification of enteropathogens. RESULTS: We enrolled 1,200 children, 596 cases and 604 controls. By univariate analysis, eight enteropathogens were associated with diarrhea: Norovirus GII (OR 5.08, 95% CI 2.10, 12.30), Adenovirus (OR 3.79, 95% CI 1.41, 10.23), typical enteropathogenic Escherichia coli (tEPEC), (OR 3.28, 95% CI 1.39, 7.73), enterotoxigenic E. coli (ETEC LT and ST producing toxins), (OR 2.58, 95% CI 0.99, 6.69), rotavirus (OR 1.91, 95% CI 1.20, 3.02), shiga toxin-producing E. coli (STEC; OR 1.77, 95% CI 1.16, 2.69), enteroaggregative E. coli (EAEC), (OR 1.45, 95% CI 1.16, 1.83) and Giardia spp. (OR 1.39, 95% CI 1.05, 1.84). By logistic regression of all enteropathogens, the best predictors of diarrhea were norovirus, adenovirus, rotavirus, STEC, Giardia spp. and EAEC. A high diarrhea severity score was associated with EAEC. CONCLUSIONS: Six enteropathogens: Norovirus, Adenovirus, Rotavirus, STEC, Giardia spp., and EAEC were associated with diarrhea in children from Brazil's semiarid region. EAEC was associated with increased diarrhea severity.


Asunto(s)
Diarrea/epidemiología , Diarrea/etiología , Infecciones por Escherichia coli/epidemiología , Giardiasis/epidemiología , Virosis/epidemiología , Brasil/epidemiología , Estudios de Casos y Controles , Diarrea/patología , Infecciones por Escherichia coli/patología , Giardiasis/patología , Humanos , Lactante , Oportunidad Relativa , Virosis/patología
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