Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Agric Food Chem ; 72(11): 5625-5635, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447070

RESUMO

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) catalyzes the oxidation of protoporphyrinogen IX to protoporphyrin IX, which is a key step in the synthesis of porphyrins in vivo. PPO inhibitors use protoporphyrinogen oxidase as the target and block the biosynthesis process of porphyrin by inhibiting the activity of the enzyme, eventually leading to plant death. In this paper, phenyl triazolinone was used as the parent structure, and the five-membered heterocycle with good herbicidal activity was introduced by using the principle of substructure splicing. According to the principle of bioisosterism, the sulfur atoms on the thiophene ring were replaced with oxygen atoms. Finally, 33 phenyl triazolinones and their derivatives were designed and synthesized, and their characterizations and biological activities were investigated. The in vitro PPO inhibitory activity and greenhouse herbicidal activity of 33 target compounds were determined, and compound D4 with better activity was screened out. The crop safety determination, field weeding effect determination, weeding spectrum determination, and crop metabolism study were carried out. The results showed that compound D4 showed good safety to corn, soybean, wheat, and peanut but poor selectivity to cotton. The field weeding effect of this compound is comparable to that of the commercial herbicide sulfentrazone. The herbicidal spectrum experiment showed that compound D4 had a wide herbicidal spectrum and a good growth inhibition effect on dicotyledonous weeds. Molecular docking results showed that compound D4 forms a hydrogen bond with amino acid residue Arg-98 in the tobacco mitochondria (mtPPO)-active pocket and forms two π-π stacking interactions with Phe-392. This indicates that compound D4 has stronger PPO inhibitory activity. This indicates that compound D4 has wide prospects for development.


Assuntos
Inibidores Enzimáticos , Herbicidas , Simulação de Acoplamento Molecular , Protoporfirinogênio Oxidase , Inibidores Enzimáticos/química , Herbicidas/química , Plantas Daninhas , Relação Estrutura-Atividade
2.
Water Res ; 250: 121032, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38157598

RESUMO

The MNBs-coagulation process as a novel and cleaning enhanced coagulation process has been demonstrated to enhance the removal efficiency of hydrophilic organics. In this study, while continuing the concept of cleaning production, the MNBs-coagulation process was first applied to the ultrafiltration process and was expected to alleviate the ultrafiltration membrane fouling. This study investigated the effect of the involvement of MNBs in coagulation-ultrafiltration process (the MC-UF process) on the fouling behaviour of ultrafiltration membrane based on the calculation of membrane resistance distribution and the fitting of membrane fouling model. In addition, the NOM removal efficiency, floc characteristics analysis and membrane hydrophilicity analysis were used to illustrate the mechanism of mitigating ultrafiltration mebrane fouling by the MC-UF process. The experimental results showed that the involvement of MNBs in the coagulation-ultrafiltration process was able to reduce the irreversible fouling and TMP by 43.1 % and 41.6 % respectively. This phenomenon could be attributed to the involvement of MNBs in the coagulation process to improve the removal efficiency of hydrophilic organics and to enhance the characteristics of flocs, thus reducing the possibility of hydrophilic organics and broken flocs entering and blocking the membrane pores. In addition, the FT-IR spectral changes before and after the floc breakage were analyzed by 2D-COS technique in this study, and it was found for the first time that the participation of MNBs in the coagulation process could change the sequence of functional group transformation within the floc, and promote the generation of hydrogen bonds between flocs by hindering the generation of hydroxyl groups (-OH), and improve the shear resistance and regrowth capacity of flocs while reducing the possibility of broken flocs entering and blocking membrane pores. In summary, the MC-UF process proposed in this study can significantly mitigate ultrafiltration membrane fouling while meeting cleaning production, providing theoretical support for the application of the process to practical engineering.


Assuntos
Ultrafiltração , Purificação da Água , Ultrafiltração/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Purificação da Água/métodos , Membranas Artificiais , Floculação , Substâncias Húmicas/análise
3.
Pestic Biochem Physiol ; 196: 105588, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945239

RESUMO

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is the last common enzyme in the biosynthetic pathway in the synthesis of heme and chlorophyll. The high-frequency use of PPO inhibitor herbicides has led to the gradual exposure of pesticide damage and resistance problems. In order to solve this kind of problem, there is an urgent need to develop new PPO inhibitor herbicides. In this paper, 16 phenylpyrazole derivatives were designed by the principle of active substructure splicing through the electron isosterism of five-membered heterocycles. Greenhouse herbicidal activity experiments and in vitro PPO activity experiments showed that the inhibitory effect of compound 9 on weed growth was comparable to that of pyraflufen-ethyl. Crop safety experiments and cumulative concentration experiments in crops showed that when the spraying concentration was 300 g ai/ha, wheat, corn, rice and other cereal crops were more tolerant to compound 9, among which wheat showed high tolerance, which was comparable to the crop safety of pyraflufen-ethyl. Herbicidal spectrum experiments showed that compound 9 had inhibitory activity against most weeds. Molecular docking results showed that compound 9 formed one hydrogen bond interaction with amino acid residue ARG-98 and two π-π stacking interactions with amino acid residue PHE-392, indicating that compound 9 had better herbicidal activity than pyraflufen-ethyl. It shows that compound 9 is expected to be a lead compound of phenylpyrazole PPO inhibitor herbicide and used as a herbicide in wheat field.


Assuntos
Herbicidas , Herbicidas/química , Protoporfirinogênio Oxidase , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Aminoácidos , Relação Estrutura-Atividade
4.
J Agric Food Chem ; 71(39): 14164-14178, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37732717

RESUMO

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) inhibitor herbicides have attracted widespread attention in recent years as ideal herbicides due to their high efficiency, low toxicity, and low pollution. In this article, 30 phenylpyrazole derivatives containing five-membered heterocycles were designed and synthesized according to the principle of bioelectronic isoarrangement and active substructure splicing. A series of structural characterizations were performed on the synthesized compounds. The herbicide activity in greenhouse was evaluated to determine their growth inhibition effect on weeds, their IC50 value through in vitro PPO enzyme activity measurement was calculated, and target compounds 2i and 3j that have herbicide effects comparable to pyraflufen-ethyl were selected. Crop safety experiments have shown that when the spraying concentration is 300 g of ai/ha, gramineous crops such as wheat, corn, and rice are more tolerant to compound 2i, with wheat exhibiting high tolerance, which is equivalent to the crop safety of pyraflufen-ethyl. Compound 2i can be used as a candidate herbicide for wheat, corn, and paddy fields, and the results are consistent with the cumulative concentration experiment. Molecular docking results showed that compound 2i interacted with the amino acid residue ARG-98 by forming two hydrogen bonds and interacted with the amino acid residue PHE-392 by forming two π-π stacking interactions, indicating that compound 2i has more excellent herbicidal activity than pyraflufen-ethyl and is expected to become a potential lead compound of phenylpyrazole PPO inhibitor herbicides.


Assuntos
Herbicidas , Herbicidas/química , Protoporfirinogênio Oxidase , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/química , Aminoácidos , Relação Estrutura-Atividade
5.
RSC Adv ; 13(7): 4729-4745, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36760302

RESUMO

Photocatalytic oxidation (PCO) based on semiconductors offers a sustainable and promising way for environmental remediation. However, the photocatalytic performance currently suffers from weak light-harvesting ability, rapid charge combination and a lack of accessible reactive sites. Ultrathin two-dimensional (2D) materials are ideal candidates to overcome these problems and become hotpots in the research fields. Herein, we demonstrate an ultrathin (<4 nm thick) Na-doped BiOCl nanosheets with {001} facets (Na-BOC-001) fabricated via a facile bottom-up approach. Because of the synergistic effect of highly exposed active facets and optimal Na doping on the electronic and crystal structure, the Na-BOC-001 showed an upshifted conduction band (CB) with stronger reduction potential for O2 activation, more defective surface for enhanced O2 adsorption, as well as the highest visible-light driven charge separation and transfer ability. Compared with the bulk counterparts (BOC-010 and BOC-001), the largest amount of active species and the best photocatalytic performance for the tetracycline hydrochloride (TC) degradation were achieved for the Na-BOC-001 under visible-light irradiation, even though it had slightly weaker visible-light absorption ability. Moreover, the effect of the Na doping and crystal facet on the possible pathways for TC degradation was investigated. This work offers a feasible and economic strategy for the construction of highly efficient ultrathin 2D materials.

6.
Water Res ; 226: 119245, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283233

RESUMO

MNBs (Micro-nano bubbles) are widely used in cleaning processes for environmental treatments, but few studies have examined the interaction of MNBs with coagulation. In this study, a novel process, i.e., MNBs-coagulation, was developed for enhanced drinking water treatment. The humic acid (HA) removal efficiency was used to evaluate the effectiveness of MNBs-coagulation for drinking water treatment. The hydrolysis component ratio of polymeric aluminum chloride (PACl) with and without MNBs, the complexation strength of HA and PACl, and flocculent functional group characterization were used to analyze the mechanism of the MNBs-coagulation process to enhance drinking water treatment. The results of a Jar test showed that the MNBs-coagulation process could improve the removal efficiency of HA (up to a 27.9% increase in DOC removal). In continuous-flow experiments to remove HA, MNBs-coagulation can increase the removal efficiency of UV254 by about 26.5% and with no significant change in turbidity. These results are attributed to the inherent hydroxyl radical generating properties of MNBs, the forced hydrolysis of PACl by MNBs to increase the Alc percentage, and the ability of MNBs to increase the complexation strength of HA with PACl. At the same time, the MNBs-coagulation process has a strong anti-interference ability, almost no interference from anions and cations such as Cl-, SO42- and Ca2+, and has a good performance in natural surface water. In summary, MNBs-coagulation has strong potential for practical applications to enhance the efficiency of drinking water treatment.


Assuntos
Água Potável , Purificação da Água , Floculação , Hidróxido de Alumínio , Purificação da Água/métodos , Substâncias Húmicas/análise , Cloreto de Alumínio
7.
J Colloid Interface Sci ; 625: 363-372, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35717850

RESUMO

Surface electronic structure of transition metal oxides plays a vital role in determining the catalytic performance. Herein, we present a selective etching strategy to tune the surface cation defect of the CuWO4 (CW) catalyst for improving the catalytic activity of volatile organic compounds (VOCs). HRTEM, SEM-EDS, EPR, and XPS show that the chelation of metal ions in acetic acid and ammonium hydroxide can help to remove a small number of surface cations in CW to form suitable W defects. Cu L-edge and O K-edge XAS, Raman, and O 1s XPS spectrum illustrate that cation defects can improve the hybrid orbits of metal-oxygen bonds, which increases the activity of surface lattice oxygen and metal sites. In-situ DRIFTS spectra reveal that CW with cation defects can easily adsorb toluene, cleave and oxidize benzene ring, and desorb CO2 because of more surface dangling bonds and active oxygen species. Therefore, the toluene conversion rates of CW-Aci and CW-Alk are much higher than CW in VOCs degradation and the catalytic performance improved 33 times and 22 times at 200 °C, respectively. This study offers a new pathway in engineering surface electronic structure and highlights the interplay between cation defects and active oxygen species.

8.
Colloids Surf B Biointerfaces ; 209(Pt 1): 112208, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34814092

RESUMO

Infection, oxidative stress, and inflammation are the major obstacles to cutaneous wound healing. Designing adhesive wound dressings with inherent antibacterial and antioxidant properties are highly desirable. Herein, a series of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-doped multifunctional hydrogels were facilely prepared by combining quaternized carboxymethyl chitosan (QCMCS) and oxidized hyaluronate (HA-CHO). Schiff base crosslinking between amino groups in QCMCS and aldehyde groups in HA-CHO not only constructed hydrogel networks but also endowed hydrogels with good self-healing property. The hydrogel exhibited adjustable tissue adhesiveness, degradability, and rheological properties by changing the content of TEMPO groups. Moreover, the hydrogels presented excellent inherent antibacterial and antioxidant properties, along with the porous structures, swelling ability, good cytocompatibility and low hemolysis ratio, which are beneficial to promoting wound healing process. Overall, the TEMPO hydrogel showed excellent therapeutic effect in mice skin defect model, giving the hydrogel with fitness as wound dressings for treating skin wounds.


Assuntos
Quitosana , Hidrogéis , Adesivos , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Camundongos , Cicatrização
9.
J Environ Manage ; 269: 110716, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32560981

RESUMO

Household consumption activities affect energy and water consumption directly and indirectly. Based on input-output modeling, this paper divided Chinese urban and rural residents into 12 groups, and investigated the impact of the consumption activities of residents with different levels of income on China's energy and water consumption from the perspective of consumers. Two main results were found. 1) In 2012, the energy consumption caused by the consumption activities of the highest-income urban residents accounted for 17.3% of the total energy consumption. For water resources, the per capita water withdrawal and consumption of the highest-income urban residents reached 481.21 m3 and 284.45 thousand m3, 6 times more than that of the low-income rural residents. 2) We identified medium and medium-high income urban residents as the key groups of residents. From the perspective of the industrial sectors, the key sectors for high energy consumption and water usage included the Electricity and Agricultural sectors, and we identified the Electricity sector as the key sector for the water and energy nexus of the residential sectors. The conclusions of this paper have pertinence for policymaking, and they provide an appropriate policy basis for guiding residents' energy and water consumption.


Assuntos
Ingestão de Líquidos , Características da Família , China , Humanos , Renda , Recursos Hídricos
10.
Langmuir ; 32(46): 12184-12189, 2016 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-27800686

RESUMO

Supramolecular gels with hierarchical order and complexity have been assembled. The gels contain well-defined Ag4L2 luminescent supramolecular cages as cores, which are cross-linked via Ag-P coordination bonding. The resulting gels are highly luminescent and exhibit rich stimuli-responsive behaviors toward mechanical and chemical (nitroexplosive and anions) stimuli. The gels could be transformed to highly luminescent crystal materials upon addition of halogen anions, in which only traces of lumiphor are accommodated in a host crystal matrix.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA