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1.
J Agric Food Chem ; 70(45): 14352-14366, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36326728

RESUMO

Diuron [DU; 3-(3,4-dichlorophenyl)-1,1-dimethylurea], a widely used herbicide for weed control, arouses ecological and health risks due to its environment persistence. Our findings revealed that DU at 0.125-2.0 mg L-1 caused oxidative damage to rice. RNA-sequencing profiles disclosed a globally genetic expression landscape of rice under DU treatment. DU mediated downregulated gene encoding photosynthesis and biosynthesis of protein, fatty acid, and carbohydrate. Conversely, it induced the upregulation of numerous genes involved in xenobiotic metabolism, detoxification, and anti-oxidation. Furthermore, 15 DU metabolites produced by metabolic genes were identified, 7 of which include two Phase I-based and 5 Phase II-based derivatives, were reported for the first time. The changes of resistance-related phytohormones, like JA, ABA, and SA, in terms of their contents and molecular-regulated signaling pathways positively responded to DU stress. Our work provides a molecular-scale perspective on the response of rice to DU toxicity and clarifies the biotransformation and degradation fate of DU in rice crops.


Assuntos
Herbicidas , Oryza , Diurona/metabolismo , Oryza/genética , Oryza/metabolismo , Herbicidas/farmacologia , Herbicidas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Estresse Oxidativo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Anal Bioanal Chem ; 413(2): 389-401, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33145646

RESUMO

Because of its widespread distribution in the environment, bisphenol A (BPA) has become a global concern as an endocrine disruptor and a threat to human health through the food chain. Thus an efficient determination method is urgently needed for monitoring the levels of BPA. Herein, a novel electrochemical technique for the detection of BPA was performed by synchronous extraction and pre-concentration of BPA onto magnetic molecularly imprinted polymer (BMMIP), with subsequent readout on a magneto-actuated glassy carbon electrode (MGCE) by differential pulse voltammetry. Compared to the current methods of BPA determination, this BMMIP-based electrochemical sensor (BMMIPs@MGCE) not only simplifies the sample handling procedures substantially, without filtration, centrifugation, or other complex operations, but also can be easily renewed by a controllable magnetic field. As a sensor component, the core-shell BMMIPs exhibited excellent binding capacity (Qe = 82.5 mg g-1), short adsorption equilibrium time (30 s), and outstanding selectivity (k' = 7.239) towards BPA, as well as stability and recyclability. Importantly, the BMMIPs@MGCE sensor was successfully applied for the on-site monitoring and rapid detection of BPA in complicated real-world specimens, with good recoveries (81.31-119.77%) and a low limit of detection (0.133 µmol L-1). Therefore, the stable and low-cost BMMIPs@MGCE sensor provides a new approach for the rapid determination of BPA in the field of environmental control and food safety. Graphical abstract.

3.
Environ Sci Pollut Res Int ; 27(10): 11246-11259, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31960244

RESUMO

Triclosan (TCS) is a broad-spectrum antimicrobial agent that is broadly used in personal care products. It has been shown to cause the contamination of a variety of aquatic environments. Since algae has been the primary producers of aquatic ecosystems, understanding the toxicological mechanisms and the metabolic fate of TCS is vital for assessing its risk in an aquatic environment. In our study, 0.5-4 mg L-1 TCS treatments for 72 h in a culture of Chlamydomonas reinhardtii (C. reinhardtii) showed progressive inhibition of cell growth and reduced the chlorophyll content. The EC50 value of C. reinhardtii after 72 h was 1.637 mg L-1, which showed its higher level of resistance to TCS in comparison with other algal species. The exposure to TCS led to oxidative injuries of algae in relation to the increment of malonaldehyde content, cell membrane permeability, and H2O2 levels. Furthermore, the oxidative stress from TCS stimulated a series of antioxidant enzyme activities and their gene expressions. Simultaneously, the accumulated TCS in C. reinhardtii arouses the detoxification/degradation-related enzymes and related gene transcriptions. In the medium, approximately 82% of TCS was removed by C. reinhardtii. Importantly, eight TCS metabolites were identified by ultra-performance liquid chromatography-high-resolution mass spectrometry and their relative abundances were measured in a time-course experiment. Six of these metabolites are reported here for the first time. The metabolic pathways of triclosan via C. reinhardtii including reductive dechlorination, hydroxylation, sulfhydrylation, and binding with thiol/cysteine/GSH/glycosyl were manifested to broaden our understanding of the environmental fate of TCS. Graphical Abstract.


Assuntos
Chlamydomonas reinhardtii , Triclosan/análise , Poluentes Químicos da Água/análise , Bioacumulação , Ecossistema , Peróxido de Hidrogênio
4.
Chemosphere ; 238: 124640, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524609

RESUMO

Triclosan (TCS) is a kind of chronic toxicity to aquatic organisms. Due to its highly effective antimicrobial, TCS has been widely applied in personal-care products, which naturally poses a potential risk to the ecological system and human health since its release into water-ecological environment. Therefore, it urgently demands a selective, easily separated, recyclable, and low-cost adsorbent to remove the residues of TCS from aquatic environments. In this study, a novel magnetic molecularly imprinted nano-polymers (TMIPs) were prepared for selective adsorption and convenient collection of TCS in aquatic samples, based on a core-shell technique using TCS as template molecule and SiO2-coated Fe3O4 nanoparticles as the support substrate. The functional groups, particle size, morphology and magnetic property of TMIPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy and vibrating sample magnetometer, respectively. The obtained TMIPs possessed excellent adsorption capacity (Qe = 53.12 mg g-1), speedy adsorption equilibrium time (2 min) and high selectivity (k' = 6.321) for TCS. Moreover, the pH-tolerance and stability tests manifested that the adsorption capacity of TMIPs for TCS was acid-resistance and could retain 94.2% of the maximum Qe after 5 times removal-regeneration cycles. The feature of magnetically susceptibility can simplify the procedures of sample handling in TCS determination, because the TMIPs of TCS are easy to be recycled from aquatic samples. As an application demonstration, the toxicity test in microalgae confirmed that a tiny amount of TMIPs could significantly eliminate the toxic effect of TCS on Chlamydomonas reinhardtii via the efficient binding with TCS.


Assuntos
Magnetismo/métodos , Impressão Molecular , Nanopartículas/química , Triclosan/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Antibacterianos/isolamento & purificação , Antibacterianos/toxicidade , Cosméticos/química , Cosméticos/toxicidade , Impressão Molecular/métodos , Tamanho da Partícula , Polímeros/química , Dióxido de Silício/química , Triclosan/toxicidade
5.
Ecotoxicol Environ Saf ; 177: 66-76, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30974245

RESUMO

A novel magnetic MIPs (DUMIPs) was prepared by surface molecular imprinting method using superparamagnetic core-shell nanoparticle (Fe3O4@SiO2) as the sacrificial support matrix, herbicide diuron as template, α-methacrylic acid as the functional monomer, trimethylolpropane trimethacrylate as the crosslinker, azobisisobutyronitrile as the initiator, and acetonitrile as the porogen. Highly cross-linked porous surface and excellent magnetic property were characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy, and vibrating sample magnetometer, respectively. The adsorption capacity of DUMIPs was 8.1 mg g-1, 2.6-fold over its corresponding non-imprinted polymers (DUNIPs). The adsorption in DUMIPs was considered as multilayer adsorption and posed high affinity to diuron, due to the better fitting to Freundilich isotherm. Competitive recognition study demonstrated DUMIPs had highly selective binding diuron. DUMIPs, as an influential sorbent has been used for selective extraction of diuron from environmental samples (paddy field water, paddy soil and grain seedlings) and the elution was determined by high efficiency liquid chromatography (HPLC). In this analytical method, various factors affecting the extraction efficiency such as pH, sorbent dosage, utilization efficiency and volumes of eluent were simultaneously investigated. Under the optimal conditions, the linearity of the method obtained is in the range of 0.02-10.0 mg L-1. The limit of detection is 0.012 mg L-1. In four spiked levels (0.04, 0.2, 1.0, and 4.0 mg kg-1), the recoveries of diuron in real samples are in the range of 83.56%-116.10% with relative standard deviations in the range of 1.21-6.81%. Importantly, compared to C18-SPE column, the MMIPs exhibited convenient separation by external magnetic field, strong clean-up capacity, and selective enrichment for diuron. Thus, the DUMIPs-based method is great potential for efficient sample preparation in the determination of trace amounts of diuron residues in complex matrices.


Assuntos
Diurona/análise , Herbicidas/análise , Impressão Molecular/métodos , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Diurona/química , Herbicidas/química , Magnetismo , Metacrilatos/química , Nanopartículas/química , Polímeros/química , Porosidade , Dióxido de Silício/química , Água/química
6.
PLoS One ; 9(3): e91361, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24625887

RESUMO

A series of novel 1,4-dihydro-2,6- dimethyl-3,5-pyridinedicarboxamides were synthesized and characterized by infrared absorption spectrum (IR), proton nuclear magnetic resonance (1H NMR), elemental analysis, ultraviolet spectrum (UV), and fluorescence techniques, together with X-ray single crystal diffraction. The results of density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations provided a reasonable explanation on the molecular structures, the molecular frontier orbital, and the spectra of electronic absorption and emission. The present work will be helpful to systematically understanding of the structures and the optical properties of 1,4-dihydropyridines for studying the structure-activity relationship and to develop new drugs and their analytical methods.


Assuntos
Amidas/química , Cristalografia por Raios X , Piridinas/química , Espectrofotometria Ultravioleta , Desenho de Fármacos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Piridinas/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 8): o2419, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22904870

RESUMO

The title compound, C(20)H(17)N(3)O(2)S(2), was synthesized by the reaction of 2-(1,5-diphenyl-1H-pyrazol-3-yl-oxy)acetic acid and thia-zolidine-2-thione. The C-linked benzene ring, N-linked benzene ring and thia-zolidine-2-thione ring are twisted 31.33 (2), 62.87 (1) and 82.71 (2)°, respectively, from the plane of the bridging 1H-pyrazole ring. The phenyl rings are oriented at a dihedral angle of 72.16 (2)°.

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