Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Microorganisms ; 12(7)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39065027

RESUMEN

Phytoremediation is recognized as an environmentally friendly technique. However, the low biomass production, high time consumption, and exposure to combined toxic stress from contaminated media weaken the potential of phytoremediation. As a class of plant-beneficial microorganisms, arbuscular mycorrhizal fungi (AMF) can promote plant nutrient uptake, improve plant habitats, and regulate abiotic stresses, and the utilization of AMF to enhance phytoremediation is considered to be an effective way to enhance the remediation efficiency. In this paper, we searched 520 papers published during the period 2000-2023 on the topic of AMF-assisted phytoremediation from the Web of Science core collection database. We analyzed the author co-authorship, country, and keyword co-occurrence clustering by VOSviewer. We summarized the advances in research and proposed prospective studies on AMF-assisted phytoremediation. The bibliometric analyses showed that heavy metal, soil, stress tolerance, and growth promotion were the research hotspots. AMF-plant symbiosis has been used in water and soil in different scenarios for the remediation of heavy metal pollution and organic pollution, among others. The potential mechanisms of pollutant removal in which AMF are directly involved through hyphal exudate binding and stabilization, accumulation in their structures, and nutrient exchange with the host plant are highlighted. In addition, the tolerance strategies of AMF through influencing the subcellular distribution of contaminants as well as chemical form shifts, activation of plant defenses, and induction of differential gene expression in plants are presented. We proposed that future research should screen anaerobic-tolerant AMF strains, examine bacterial interactions with AMF, and utilize AMF for combined pollutant removal to accelerate practical applications.

2.
Environ Sci Technol ; 58(26): 11568-11577, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889013

RESUMEN

Dinitrogen pentoxide (N2O5) plays an essential role in tropospheric chemistry, serving as a nocturnal reservoir of reactive nitrogen and significantly promoting nitrate formations. However, identifying key environmental drivers of N2O5 formation remains challenging using traditional statistical methods, impeding effective emission control measures to mitigate NOx-induced air pollution. Here, we adopted machine learning assisted by steady-state analysis to elucidate the driving factors of N2O5 before and during the 2022 Winter Olympics (WO) in Beijing. Higher N2O5 concentrations were observed during the WO period compared to the Pre-Winter-Olympics (Pre-WO) period. The machine learning model accurately reproduced ambient N2O5 concentrations and showed that ozone (O3), nitrogen dioxide (NO2), and relative humidity (RH) were the most important driving factors of N2O5. Compared to the Pre-WO period, the variation in trace gases (i.e., NO2 and O3) along with the reduced N2O5 uptake coefficient was the main reason for higher N2O5 levels during the WO period. By predicting N2O5 under various control scenarios of NOx and calculating the nitrate formation potential from N2O5 uptake, we found that the progressive reduction of nitrogen oxides initially increases the nitrate formation potential before further decreasing it. The threshold of NOx was approximately 13 ppbv, below which NOx reduction effectively reduced the level of night-time nitrate formations. These results demonstrate the capacity of machine learning to provide insights into understanding atmospheric nitrogen chemistry and highlight the necessity of more stringent emission control of NOx to mitigate haze pollution.


Asunto(s)
Contaminantes Atmosféricos , Atmósfera , Aprendizaje Automático , Contaminantes Atmosféricos/análisis , Atmósfera/química , Óxidos de Nitrógeno/análisis , Contaminación del Aire , Ozono/análisis , Monitoreo del Ambiente/métodos , Dióxido de Nitrógeno/análisis
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 309: 123806, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154307

RESUMEN

As one of the major reactive oxygen species (ROS), superoxide anion (O2•-) is engaged in maintaining redox homeostasis in the cell microenvironment. To identify the pathological roles in related disorders caused by abnormal expression of O2•-, it is of great significance to monitor and track the fluctuation of O2•- concentration in vivo. However, the low concentration of O2•- and the interference caused by tissue autofluorescence make the development of an ideal detection methodology full of challenges. Herein, a "Turn-On" chemical response near-infrared (NIR) fluorescence probe Dcm-Cu-OTf for O2•- detection in inflamed models, was constructed by conjugating the NIR fluorophore (dicyanisophorone derivative) with an O2•- sensing moiety (trifluoromethanesulfonate). Dcm-Cu-OTf exerted about 140-fold fluorescence enhancement after reacting 200 µM O2•- with an excellent limited of detection (LOD) as low as 149 nM. Additionally, Dcm-Cu-OTf exhibited a super large Stokes shift (260 nm) and high selectivity over other bio-analytes in stimulated conditions. Importantly, Dcm-Cu-OTf showed low toxicity and enabled imaging of the generation of O2•- in the Lipopolysaccharide (LPS)-stimulated HeLa cells, zebrafish, and LPS-induced inflamed mice. The present study provided a potential and reliable detection tool to inspect the physiological and pathological progress of O2•- in living biosystems.


Asunto(s)
Colorantes Fluorescentes , Superóxidos , Humanos , Ratones , Animales , Colorantes Fluorescentes/toxicidad , Superóxidos/metabolismo , Pez Cebra/metabolismo , Células HeLa , Lipopolisacáridos/toxicidad , Imagen Óptica
4.
Environ Sci Technol ; 57(39): 14638-14647, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37738177

RESUMEN

Chlorine (Cl) radicals from photolabile chlorine species are highly reactive and can affect the fate of air pollutants in the atmosphere. Although several campaigns have been conducted, typically in coastal environments, long-term observations of reactive chlorine species and their impacts on atmospheric oxidation capacities (AOCs) are lacking. Here, we report nearly full-year observations of Cl2 and ClNO2 levels in Beijing and evaluate their impacts on the AOC with a box model coupled with Cl chemistry. Cl radicals promote the circulation of OH-HO2-RO2 by accelerating the OH chain lengths by up to 12.6% on average, hence boosting the AOC, especially in the winter or spring. This promotion effect is nonlinearly dependent on the VOC and NOx concentrations, thus leading to a slight shift in ozone formation from a VOC-sensitive regime to a transition regime with seasonal differences. Given the ubiquitous reactive chlorines in polluted inland urban regions, the AOCs and the formation of secondary pollutants will be underestimated if the reactive chlorine species are neglected.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Cloro , Ozono/análisis , Atmósfera , Cloruros
5.
Molecules ; 28(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37375339

RESUMEN

In this study, we explorethe synthesis of binaphthyl-based chiral macrocyclic hosts for the first time. They exhibited the selective recognition abilities of iodide anions which can be favored over those of other anions (AcO-, NO3-, ClO4-, HSO4-, Br-, PF6-, H2PO4-, BF4-, and CO3F3S-), as confirmed by UV-vis, HRMS, and 1H NMR spectroscopy experiments, as well as DFT calculations. Neutral aryl C-H···anion interactions play an important role in the formation complexes. The recognition process can be observed by the naked eye.

6.
Langmuir ; 39(24): 8503-8515, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37284830

RESUMEN

Catalytic oxidation has been extensively studied as a promising technology for the removal of toluene from industrial waste gases and indoor air. However, the debate regarding the oxidation mechanism is far from resolved. CexMn1-xO2 catalysts with different mixing ratios are prepared by the sol-gel method and found to exhibit better catalytic activities for toluene oxidation than a single oxide. Characterizations and theoretical calculations reveal that the doped Mn increases the number of oxygen vacancies and the ability of oxygen vacancies to activate aromatic rings, which promotes the rate-determining step of toluene oxidation, i.e., ring-opening reactions. The oxidation products detected by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and Vocus proton transfer reaction mass spectrometry (Vocus-PTR-MS) show that the doped Mn significantly improves the ring-opening efficiency and subsequently yields more short-chain products, such as pyruvic acid and acetic acid. A comprehensive oxidation pathway of toluene is refined in this work.

7.
NPJ Clim Atmos Sci ; 6(1): 37, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214635

RESUMEN

Wintertime meteorological conditions are usually unfavorable for ozone (O3) formation due to weak solar irradiation and low temperature. Here, we observed a prominent wintertime O3 pollution event in Shijiazhuang (SJZ) during the Chinese New Year (CNY) in 2021. Meteorological results found that the sudden change in the air pressure field, leading to the wind changing from northwest before CNY to southwest during CNY, promotes the accumulation of air pollutants from southwest neighbor areas of SJZ and greatly inhibits the diffusion and dilution of local pollutants. The photochemical regime of O3 formation is limited by volatile organic compounds (VOCs), suggesting that VOCs play an important role in O3 formation. With the developed O3 formation path tracing (OFPT) approach for O3 source apportionment, it has been found that highly reactive species, such as ethene, propene, toluene, and xylene, are key contributors to O3 production, resulting in the mean O3 production rate (PO3) during CNY being 3.7 times higher than that before and after CNY. Industrial combustion has been identified as the largest source of the PO3 (2.6 ± 2.2 ppbv h-1), with the biggest increment (4.8 times) during CNY compared to the periods before and after CNY. Strict control measures in the industry should be implemented for O3 pollution control in SJZ. Our results also demonstrate that the OFPT approach, which accounts for the dynamic variations of atmospheric composition and meteorological conditions, is effective for O3 source apportionment and can also well capture the O3 production capacity of different sources compared with the maximum incremental reactivity (MIR) method.

8.
Molecules ; 28(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36838835

RESUMEN

A turn-on fluorescent probe, cage 1, was efficiently self-assembled by condensing 4,4'-(benzothiadiazole-4,7-diyl)dibenzaldehyde and TREN in chloroform. The formation of cage 1 was characterized and confirmed by NMR spectroscopy, mass spectrometry, and theoretical calculations. The yield of cage 1 could be controlled by tuning the reaction conditions, such as the precursor concentration. Interestingly, the addition of 10 equiv of Cd2+ relative to cage 1 could increase the fluorescence almost seven-fold. 1H NMR and fluorescence experiments indicating fluorescence enhancement may be caused by the decomposition of cage 1. Such a high selectivity toward Cd2+ implies that the cage could potentially be employed in cadmium detection.


Asunto(s)
Cadmio , Tiadiazoles , Cadmio/química , Microscopía Fluorescente/métodos , Cloroformo , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 293: 122428, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36773422

RESUMEN

Hydrogen sulfide (H2S) plays a substantial role as a messenger in the physiological and pathological processes of many diseases. Recently, the fluorescence probe of H2S based on organic dye has attracted great attention. However, the emission of many probes is in the UV-vis region (400-600 nm), so it has the disadvantages of shallow tissue penetration and more vulnerable to spontaneous fluorescence interference. Although several H2S probes have been developed that emit more than 650 nm, there is a complex structure difficult to synthesize or unstable in storage. Aimed at simply structural and easily synthesized H2S fluorescent probes with emission wavelength more than 650 nm, a novel near-infrared (NIR) probe (NIR-H2S) here was rationally designed with 4-(2-carboxyphenyl)-7-(diethylamino)-2-(4-hydroxystyryl)chromenylium (NIR-OH) as a fluorescent dye and 2,4-dinitrophenyl moiety as a recognition group. Addition of H2S, the "turn-on" NIR fluorescence response at 736 nm of NIR-H2S was displayed, accompanied by a visual colour change from purple to green when excited at 686 nm. As an easily acquisitive H2S probe, NIR-H2S has been successfully applied to cell imaging for H2S detection with the advantages such as long fluorescence emission, low toxicity, high sensitivity and strong selectivity.


Asunto(s)
Sulfuro de Hidrógeno , Humanos , Sulfuro de Hidrógeno/química , Colorantes Fluorescentes/química , Imagen Óptica , Microscopía Fluorescente/métodos , Espectrometría de Fluorescencia , Células HeLa
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 2): 120585, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34782266

RESUMEN

Detection of selenocysteine (Sec) content in cells by fluorescence probe is of great significance for the identification of human related diseases. To achieve fast and sensitive detection of Sec, two isomers A4 and B4 as turn-on fluorescent probes to detect Sec were designed and synthesized. Both A4 and B4 display fast turn-on response, high selectivity and sensitivity toward Sec, which can be applied for fluorescence imaging of Sec in living cells. Compared with B4, A4 has a larger Stokes shift (125 nm), wider pH range (5-10) and lower detection limit (65.4 nM) due to its ESIPT (excited state intramolecular proton transfer) effect. In view of the detection performance of these two probes, they can be used as effective tools for detecting Sec in biological systems.


Asunto(s)
Imagen Óptica , Selenocisteína , Colorantes Fluorescentes , Células HeLa , Humanos , Protones
11.
Eur J Med Chem ; 227: 113946, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34775332

RESUMEN

Epigentic enzymes histone deacetylases (HDACs) catalyze the removal of acetyl groups from the ε-N-acetylated lysine residues of various protein substrates including both histone and non-histone proteins. Different HDACs have distinct biological functions and are recruited to specific regions of the genome. Due to their important biological functions, HDACs have been validated in clinics for anticancer therapy, and are being explored for potential treatment of several other diseases such as Alzheimer disease (AD), metabolic disease, viral infection, and multiple sclerosis, etc. Besides five approved drugs, there are more than thirty HDACs inhibitors currently being investigated in clinical trials. Centering on the advances of drug discovery programs in this field since 2020, this review discusses HDACs inhibitors from the aspects of the structure-based rational design, isoform selectivity, pharmacology, and toxicology of the compounds of interest. The hope is to provide the medicinal chemistry community with up-to-date information and to accelerate the drug discovery programs in this area.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Química Farmacéutica , Inhibidores de Histona Desacetilasas/química , Humanos , Estructura Molecular
12.
J Basic Microbiol ; 61(10): 947-957, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34387369

RESUMEN

Worldwide marine compound contamination by petroleum products and heavy metals is a burgeoning environmental concern. Pseudoalteromonas, prevalently distributed in marine environment, has been proven to degrade petroleum and plays an essential role in the fate of oil pollution under the combined pollution. Nevertheless, the research on the reference genes is still incomplete. Therefore, this study aims to thoroughly investigate the reference genes represented by Pseudoalteromonas sp. JSTW via whole-genome sequencing. Next-generation sequencing technology unfolded a genome of 4,026,258 bp, database including Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were utilized to annotate the genes and metabolic pathways conferring to petroleum hydrocarbon degradation. The results show that common alkane and aromatic hydrocarbon degradation genes (alkB, ligB, yqhD, and ladA), chemotaxis gene (MCP, cheA, cheB, pcaY, and pcaR), heavy-metal resistance, and biofilm genes (σ54, merC, pcoA, copB, etc.) were observed in whole-genome sequence (WGS) of JSTW, which indicated that strain JSTW could potentially cope with combined pollution. The degradation efficiency of naphthalene in 60 h by JSTW was 99% without Cu2+ and 67% with 400 mg L-1 Cu2+ . Comparative genome analysis revealed that genomes of Pseudoalteromonas lipolytica strain LEMB 39 and Pseudoalteromonas donghaensis strain HJ51 shared similarity with strain JSTW, suggesting they are also the potential degradater of petroleum hydrocarbons under combined pollution. Therefore, this study provides a WGS annotation and reveals the mechanism of response to combined pollution of Pseudoalteromonas sp. JSTW.


Asunto(s)
Genómica , Metales Pesados/metabolismo , Petróleo/metabolismo , Petróleo/microbiología , Pseudoalteromonas/clasificación , Pseudoalteromonas/genética , Pseudoalteromonas/aislamiento & purificación , Alcanos , Biodegradación Ambiental , Biopelículas , Secuenciación de Nucleótidos de Alto Rendimiento , Hidrocarburos , Contaminación por Petróleo , Filogenia , Pseudoalteromonas/metabolismo , ARN Ribosómico 16S/genética
13.
Macromol Rapid Commun ; 42(17): e2100299, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34173296

RESUMEN

In this work, a naphthalene-based macrocycle prism[5]arene (NP5 OCH3 ) is developed as a novel kind of photoinitiator. When NP5 OCH3 is irradiated under light, the bond between methylene and naphthalene can be quickly broken owning to the existence of ring tension. The macrocycle is cleaved to linear oligomer biradicals, which can effectively initiate the free radical photopolymerization of acrylate monomers. Compared with conventional photoinitiators, NP5 OCH3 has strong light absorption in the wavelength range of 365-405 nm, so it can well match the environment-friendly light-emitting diodes (LEDs) light source to realize highly efficient initiation. In addition, there is no small molecule fragment generated during NP5 OCH3 fracture, and the resulted linear oligomer biradicals can be immobilized in the polymer after initiating polymerization, so NP5 OCH3 photoinitiators show much lower migration rate and cytotoxicity. Cleavable macrocycle prismarene may provide a new idea for the design of safe and efficient photoinitiators matching long wavelength light.


Asunto(s)
Luz , Polímeros , Radicales Libres , Polimerizacion
14.
Molecules ; 25(21)2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33126726

RESUMEN

Since the fluctuation of cellular selenocysteine (Sec) concentration plays an all-important role in the development of numerous human disorders, the real-time fluorescence detection of Sec in living systems has attracted plenty of interest during the past decade. In order to obtain a faster and more sensitive small organic molecule fluorescence sensor for the Sec detection, a new ratiometric fluorescence sensor Q7 was designed based on the fluorescence resonance energy transfer (FRET) strategy with coumarin fluorophore as energy donor and 4-hydroxy naphthalimide fluorophore (with 2,4-dinitrobenzene sulfonate as fluorescence signal quencher and Sec-selective recognition site) as an energy acceptor. The sensor Q7 exhibited only a blue fluorescence signal, and displayed two well distinguished emission bands (blue and green) in the presence of Sec with ∆λ of 68 nm. Moreover, concentrations ranging of quantitative detection of Sec of Q7 was from 0 to 45 µM (limit of detection = 6.9 nM), with rapid ratiometric response, high sensitivity and selectivity capability. Impressively, the results of the living cell imaging test demonstrated Q7 has the potentiality of being an ideal sensor for real-time Sec detection in biosystems.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia/instrumentación , Imagen Óptica/instrumentación , Selenocisteína/metabolismo , Células A549 , Humanos
15.
Sensors (Basel) ; 20(17)2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32846934

RESUMEN

The content of selenocysteine in cells has an important effect on a variety of human diseases, and the detection of selenocysteine by fluorescent sensors in vivo has shown many advantages. In order to further develop fast-reaction-time, good-selectivity, and high-sensitivity long-wavelength selenocysteine fluorescent sensors, we designed and synthesized the compound YZ-A4 as a turn-on fluorescent sensor to detect the content of selenocysteine. The quantitative detection range of the sensor YZ-A4 to selenocysteine was from 0 to 32 µM, and the detection limit was as low as 11.2 nM. The sensor displayed a rapid turn-on response, good selectivity, and high sensitivity to selenocysteine. Finally, we have demonstrated that YZ-A4 could be used for fluorescence imaging of selenocysteine in living cells.


Asunto(s)
Colorantes Fluorescentes , Selenocisteína , Humanos , Microscopía Fluorescente , Imagen Óptica , Espectrometría de Fluorescencia
16.
Appl Microbiol Biotechnol ; 104(11): 4757-4770, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32291487

RESUMEN

Ceaseless growth in human population led to high demand in everything. Currently, the world largely depends on petroleum-based "all material synthesis" scheme. On the other hand, depletion of fossil-based resources and their huge impact on environmental pollution have forced us to search for sustainable and eco-friendly alternative resources. In this context, the notion to utilize waste biomass could possibly provide environmental and economic benefits. This study was carefully designed to critically review state of the art in the transformation of waste biomass into value-added products. Even though extensive reviews on biomass utilization have been published in the past few years, the current study basically focused on new trends and prospective in this area. Here, global biomass potential, research developments and practices, novel biomass transformation approaches, and future perspectives were broadly discussed. More importantly, in addition to revising published researches, already implemented and ongoing large-scale projects on valorization of waste biomass have been assessed. Therefore, this study is believed to give crucial information on the current status and future direction of waste biomass utilization so as to accomplish the quest towards green economy.Key Points • Huge biomass potential and dramatically increase in R&D trends on waste biomass.• Selection of appropriate waste biomass valorization techniques. • Development of efficient and feasible waste biomass transformation technology. • Coproduction of low-value, high-volume and high-value, low volume products.


Asunto(s)
Biomasa , Biotecnología/métodos , Biotransformación , Residuos , Biocombustibles , Biotecnología/tendencias , Investigación/tendencias
17.
Med Sci Monit ; 21: 1408-13, 2015 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-25978873

RESUMEN

BACKGROUND: Although many studies have estimated the association between the butyrylcholinesterase (BCHE) K variant and Alzheimer's disease (AD) risk, the results are still controversial. We thus conducted this meta-analysis. MATERIAL/METHODS: We searched NCBI, Medline, Web of Science, and Embase databases to find all eligible studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association. RESULTS: We found a significant association between BCHE K variant and AD risk (OR=1.20; 95% CI 1.03-1.39; P=0.02). In the stratified analysis by ethnicity, we observed a significant association between BCHE K variant and AD risk in Asians (OR=1.32; 95% CI 1.02-1.72; P=0.04). However, no significant association between BCHE K variant and AD risk in Caucasians was found (OR=1.14; 95% CI 0.95-1.37; P=0.16). When stratified by the age of AD onset, we found that late-onset AD (LOAD) was significantly associated with BCHE K variant (OR=1.44; 95% CI 1.05-1.97; P=0.02). No significant association between BCHE K variant and early-onset AD (EOAD) risk was observed (OR=1.16; 95% CI 0.89-1.51; P=0.27). Compared with non-APOE ε4 and non-BCHE K carriers, no significant association between BCHE K variant and AD risk was found (OR=1.11; 95% CI 0.91-1.35; P=0.30). However, APOE ε4 carriers showed increased AD risk in both non-BCHE K carriers (OR=2.81; 95% CI 1.75-4.51; P=0.0001) and BCHE K carriers (OR=3.31; 95% CI 1.82-6.02; P=0.0001). CONCLUSIONS: The results of this meta-analysis indicate that BCHE K variant might be associated with AD risk.


Asunto(s)
Enfermedad de Alzheimer/genética , Butirilcolinesterasa/genética , Polimorfismo de Nucleótido Simple , Edad de Inicio , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/etnología , Apolipoproteína E4/genética , Pueblo Asiatico/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Oportunidad Relativa , Sesgo de Publicación , Riesgo , Sensibilidad y Especificidad , Población Blanca/genética
18.
Pest Manag Sci ; 69(10): 1121-30, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23436572

RESUMEN

BACKGROUND: In previous studies, scientists found that, when spirotetramat was introduced into plants or animals, it was mainly metabolised at positions C-4 and C-8. That is to say, these two functional positions potentially played an important role in spirotetramat's bioactivities. In order to develop novel insecticides or miticides, the present authors designed and synthesised 35 spirotetramat analogues based on metabolite structures. RESULTS: All of the analogues have been identified on the basis of (1)H NMR, ESI-MS and elemental analysis data. The activities of these analogues were evaluated against three organisms, and biological assays indicated that compounds 5f, 5h and 5u possessed better insecticidal activities against bean aphids (Aphis fabae) than the lead compound spirotetramat. The LC50 of 5f, 5h and 5u against bean aphids reached 0.42, 0.28 and 2.53 mg L(-1) respectively. Moreover, some compounds possessed comparable activities against carmine spider mite (Tetranychus cinnabarinus) and oriental armyworm (Mythimna sepatara) with spirotetramat. The structure-activity relationships (SARs) indicated that the flexible bridge at position C-4 of spirotetramat was important for its bioactivities, and the size of the group at position C-8 would have great influence on the activities. Furthermore, the log P values lower than 6.0 may be favourable for insecticidal activities. CONCLUSION: The present work demonstrates that some spirotetramat analogues can be used as potential lead compounds for developing novel insecticides, and preliminary SAR analysis would provide information for the utilisation of spirotetramat analogues as potential lipid biosynthesis inhibitors.


Asunto(s)
Compuestos Aza/química , Compuestos Aza/toxicidad , Insecticidas/química , Insecticidas/toxicidad , Lípidos/antagonistas & inhibidores , Compuestos de Espiro/química , Compuestos de Espiro/toxicidad , Animales , Áfidos/efectos de los fármacos , Áfidos/metabolismo , Bioensayo , Diseño de Fármacos , Lípidos/biosíntesis , Estructura Molecular , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/metabolismo , Relación Estructura-Actividad , Tetranychidae/efectos de los fármacos , Tetranychidae/metabolismo
19.
J Agric Food Chem ; 60(19): 4779-87, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22531003

RESUMEN

A series of 4-phenyl-acyl-substituted 3-(2,5-dimethylphenyl)-4-hydroxy-1-azaspiro[4.5]dec-3-ene-2,8-dione derivatives were designed and synthesized, and their structures were characterized using (1)H NMR (or (13)C NMR), mass spectrometry, and elemental analysis. The bioactivities of the new compounds were evaluated. These compounds exhibited good inhibition activities against bean aphids (Aphis fabae) and carmine spider mite (Tetranychus cinnabarinus), and 4-phenyl acyl esters showed stronger bioactivity than 4-arylesterases and alkyl esters. The results showed that compound 8-I-e, which contains a para-methoxy group on the phenyl acyl, and compound 8-I-m, which contains a para-trifluoromethyl group on the phenyl acyl, displayed potent insecticidal activity against A. fabae and T. cinnabarinus respectively. The insecticidal activity showed a clear structure-activity relationship, confirming the importance of the flexible bridge. The DFT/B3LYP/6-31(d) level method was used to calculate molecular geometries and electronic descriptors. These factors included total energy, charge distribution, and the linear orbital level of the title compounds. Quantitative structure-activity relationship studies were performed on these compounds using quantum-chemical and physicochemical parameters as independent variables and insecticidal activity as a dependent variable. Insecticidal activity was most closely correlated (r > 0.8) with quantum chemical and physicochemical parameters.


Asunto(s)
Acaricidas/química , Acaricidas/farmacología , Insecticidas/química , Insecticidas/farmacología , Acaricidas/síntesis química , Animales , Áfidos/efectos de los fármacos , Diseño de Fármacos , Insecticidas/síntesis química , Estructura Molecular , Relación Estructura-Actividad Cuantitativa , Tetranychidae/efectos de los fármacos
20.
Pest Manag Sci ; 68(1): 10-5, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21997953

RESUMEN

BACKGROUND: The development of environmentally friendly and novel structural pesticides is now an area of intense research in the agriculture field. Spirocyclic tetronic acids such as spiromesifen are typical compounds of this kind. In order to discover novel compounds with improved and broader-spectrum insecticidal activities, a series of spiromesifen derivatives were synthesised and bioassayed. RESULTS: The derivatives were identified by (1) H NMR and MS. Preliminary bioassays demonstrated that some bioactivities of compounds 5a to 5u were better and had a broader spectrum than the lead compound spiromesifen. Moreover, these compounds showed better insecticidal activities against Mythimna sepatara and Aphis fabae than acaricidal activities against Tetranychus cinnabari. Furthermore, LC(50) of 5s against Aphis fabae reached 1.09 mg L(-1) . At the same time, compounds 5g, 5i, 5k and 5r also warrant further study because of their superior bioactivities to spiromesifen. What is more, suitable carbon chain length in the 4-position ester and the log P value of these spiromesifen derivatives dramatically influenced their insecticidal activities. Butyric or pentanoic ester and a log P value of 4.0-6.0 may be preferred. CONCLUSION: The present work demonstrates that some spiromesifen derivatives can be used as potential lead compounds for developing novel insecticides and acaricides.


Asunto(s)
Áfidos/efectos de los fármacos , Insecticidas/síntesis química , Insecticidas/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Compuestos de Espiro/síntesis química , Compuestos de Espiro/toxicidad , Animales , Bioensayo , Insecticidas/química , Estructura Molecular , Compuestos de Espiro/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA