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1.
J Hazard Mater ; 469: 134098, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38522198

RESUMEN

To investigate the efficacy of epigallocatechin gallate (EGCG) and its underlying mechanism in preventing bisphenol-A-induced metabolic disorders, in this study, a mice model of metabolic disorders induced by BPA was developed to investigate the efficacy and mechanism of EGCG using microbiomes and metabolomics. The results showed that EGCG reduced body weight, liver weight ratio, and triglyceride and total cholesterol levels in mice by decreasing the mRNA expression of genes related to fatty acid synthesis (Elov16) and cholesterol synthesis (CYP4A14) and increasing the mRNA expression of genes related to fatty acid oxidation (Lss) and cholesterol metabolism (Cyp7a1). In addition, EGCG normalized BPA-induced intestinal microbial dysbiosis. Metabolic pathway analysis showed that low-dose EGCG was more effective than high-dose EGCG at affecting the biosynthesis of L-cysteine, glycerophosphorylcholine, and palmitoleic acid. These results provide specific data and a theoretical basis for the risk assessment of BPA and the utilization of EGCG.


Asunto(s)
Compuestos de Bencidrilo , Catequina/análogos & derivados , Enfermedades Metabólicas , Fenoles , Ratones , Animales , Colesterol , ARN Mensajero , Ácidos Grasos
2.
Adv Mater ; : e2313267, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38346418

RESUMEN

The development of photostimulated-motion artificial reflex arcs - a neural circuit inspired by light-driven motion reflexes - holds significant promises for advancements in robotic perception, navigation, and motion control. However, the fabrication of such systems, especially those that accommodate multiple actions and exhibit gradient responses, remains challenging. Here, a gradient-responsive photostimulated-motion artificial reflex arc is developed by integrating a programmable and tunable photoreceptor based on folded MoS2 at different twist angles. The twisted folded bilayer MoS2 used as photoreceptors can be customized via the transfer technique using patternable paraffin, where the twist angle and fold-line could be controlled. The photoluminescence (PL) intensity is 3.7 times higher at a twist angle of 29° compared to that at 0°, showing a monotonically decreasing indirect bandgap. Through tunable interlayer carrier transport, photoreceptors fabricated using folded bilayer MoS2 at different twist angles demonstrate gradient response time, enabling the photostimulated-motion artificial reflex arc for multiaction responses. They are transformed to digital command flow and studied via machine learning to control the gestures of a robotic hand, showing a prototype of photostimulated gradient-responsive artificial reflex arcs for the first time. This work provides a unique idea for developing intelligent soft robots and next-generation human-computer interfaces.

3.
Free Radic Biol Med ; 213: 274-284, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38244729

RESUMEN

Prothioconazole (PTC), a novel broad-spectrum triazole fungicide, has attracted widespread concern due to its wide use and toxicological effects on non-target organisms. However, little is known about the impact of PTC on oocyte quality and female fertility, especially on oocyte maturation and fertilization. In the present study, we reported that PTC exposure affects the oocyte developmental competence and oocyte fertilization ability to weaken female fertility. Firstly, PTC compromises oocyte development ability by disrupting spindle morphology and chromosome alignment, as well as decreasing acetylation level of α-tubulin and disrupting kinetochore-microtubule attachments. In addition, PTC compromises oocyte fertilization ability by weakening the sperm binding ability and impairing the dynamics of Juno, Cortical granule and Ovastacin. Finally, single-cell transcriptome analysis revealed that PTC exposure has potentially toxic effects on oocyte development and fertilization, which is caused by the mitochondrial dysfunction and the occurrence of oxidative stress and apoptosis. In summary, our results indicated that PTC exposure had potentially toxic effects on female fertility and led to poor oocyte quality in female mice.


Asunto(s)
Enfermedades Mitocondriales , Semen , Masculino , Femenino , Ratones , Animales , Oocitos/metabolismo , Triazoles , Estrés Oxidativo , Fertilización , Apoptosis , Enfermedades Mitocondriales/metabolismo
4.
Foods ; 13(2)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38254506

RESUMEN

Chlorantraniliprole (CAP) is a new type of diamide insecticide that is mainly used to control lepidopteran pests. However, it has been proven to be hazardous to nontarget organisms, and the effects of its residues need to be monitored. In this study, five hybridoma cell lines were developed that produced anti-CAP monoclonal antibodies (mAbs), of which the mAb originating from the cell line 5C5B9 showed the highest sensitivity and was used to develop a gold nanoparticle-based lateral flow immunoassay (AuNP-LFIA) for CAP. The visible limit of detection of the AuNP-LFIA was 1.25 ng/mL, and the detection results were obtained in less than 10 min. The AuNP-LFIA showed no cross-reactivity for CAP analogs, except for tetraniliprole (50%) and cyclaniliprole (5%). In the detection of spiked and blind samples, the accuracy and reliability of the AuNP-LFIA were confirmed by a comparison with spiked concentrations and verified by ultra-performance liquid chromatography-tandem mass spectrometry. Thus, this study provides the core reagents for establishing CAP immunoassays and a AuNP-LFIA for the detection of residual CAP.

5.
J Agric Food Chem ; 72(1): 679-689, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38064576

RESUMEN

This study systematically investigates the stereoselective metabolism and residue behavior of chiral pesticide prothioconazole enantiomers during the steaming, baking, and frying of steamed buns, bread, and deep-fried dough sticks. The results show that steaming, baking, and frying can significantly promote the degradation of the prothioconazole enantiomers. In low- and high-concentration treatments, the degradation rates of prothioconazole enantiomers were over 96.0% and 45.4%, respectively, and the residual concentration of prothioconazole-desthio enantiomers was less than 32.7 µg/kg (excluding fried processing). During the processing of steamed buns, bread, and deep-fried dough sticks, the enantiomer fraction (EF) value of the prothioconazole enantiomer was close to 0.5, and the stereoselectivity was not significant. During the processing of steamed buns (low concentration), bread (low and high concentrations), and deep-fried dough sticks (low concentration), the stereoselectivity of prothioconazole-desthio was significant, and preferential enantiomer degradation occurred. Following the analysis of 120 flour product samples, the residual risk.


Asunto(s)
Fungicidas Industriales , Plaguicidas , Fungicidas Industriales/química , Harina , Estereoisomerismo
6.
J Agric Food Chem ; 71(48): 19045-19053, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37982559

RESUMEN

Pyrrolizidine alkaloids (PAs) have been detected in tea and can threaten human health. However, the specific source of PAs in tea is still unclear. Here, 88 dried tea products collected from six major tea-producing areas in Anhui Province, China, were analyzed. The detection frequency was 76%. The content of total PAs in dried tea was between 1.1 and 90.5 µg/kg, which was all below the MRL recommended by the European Union (150 µg/kg). In the Shexian tea garden, PAs in the weeds and weed rhizospheric soil around tea plants and the fresh tea leaves were analyzed. Intermedine (Im), intermedine-N-oxide (ImNO), and jacobine-N-oxide (JbNO) were transferred through the weed-to-soil-to-tea route into the fresh tea leaves; only Im and ImNO were detected in dried tea samples. Potential risk of the total PAs in the tea infusion was assessed according to the margin of exposure method, and it might be a low concern for public health.


Asunto(s)
Camellia sinensis , Alcaloides de Pirrolicidina , Humanos , Alcaloides de Pirrolicidina/análisis , Malezas , , Medición de Riesgo , Óxidos
7.
Comput Intell Neurosci ; 2022: 8633955, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36248935

RESUMEN

Anomaly detection in videos is a challenging computer vision problem. Existing state-of-the-art video anomaly detection methods mainly focus on the structural design of deep neural networks to obtain performance improvements. Different from the main research trend, this paper focuses on combining ensemble learning and deep neural networks and proposes an approach based on ensemble generative adversarial network (GAN). In the proposed method, a set of generators and a set of discriminators are trained together, so each generator gets feedback from multiple discriminators and vice versa. Compared with a single GAN, the proposed ensemble GAN can better model the distribution of normal data to better detect anomalies. In the experiments, the performance of the proposed method is tested on two public datasets. The results show that ensemble learning significantly improves the performance of a single detection model, which outperforms some existing state-of-the-art methods.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador/métodos
8.
J Hazard Mater ; 432: 128650, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35290892

RESUMEN

Toxification metabolism of the chiral triazole fungicide prothioconazole in the environment has attracted an increasing amount of attention. To better understand the fate of prothioconazole in aquatic ecosystems and develop a treatment strategy, the stereoselective toxicity, degradation and bioconcentration of prothioconazole were investigated in water with algae at the enantiomer level. There was remarkable enantioselectivity against Chlorella pyrenoidosa, and the highly toxic S-prothioconazole was preferentially degraded with enantiomer fraction values ranging from 0.5 to 0.74. Metabolism experiment results showed that the parent compound was quickly eliminated driven by biodegradation and abiotic degradation (hydrolysis, photolysis). Fourteen phase I and two phase II metabolites involved in the reactions of hydroxylation, methylation, dechlorinating, desulfuration, dehydration and conjugation were identified, where prothioconazole-desthio was the major metabolite. The highly toxic metabolite prothioconazole-desthio persisted in water and hardly degraded with or without C. pyrenoidosa. Furthermore, the reaction system including 1 mg of cobalt coated in nitrogen doped carbon nanotubes and 0.156 g of peroxymonosulfate was used to eliminate prothioconazole-desthio. Approximately 96% prothioconazole-desthio was eliminated and transformed to low toxicity metabolites. This work provides a strategy for the risk evaluation of prothioconazole in aquatic ecosystems and proposes a workable plan for the elimination of pesticide residues in water.


Asunto(s)
Chlorella , Fungicidas Industriales , Nanotubos de Carbono , Chlorella/metabolismo , Ecosistema , Fungicidas Industriales/química , Triazoles/química , Agua
9.
Sci Total Environ ; 806(Pt 4): 150863, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34626633

RESUMEN

Enantioselective metabolism of chiral pesticide in plants is very important. In vitro system has become an effective means to study the metabolism of pesticides in plants, but the study on the metabolism of chiral pesticides has not been reported. This work compared the enantiomer metabolic behavior of acephate and its metabolite methamidophos between tea cell suspensions and excised tea stem with leaves. (±)-Acephate could be absorbed and transferred well to top leaves by the cut end of excised stem after 24 h. (±)-Methamidophos was derived from the metabolism of (±)-acephate in tea plants at 3-5% in leaves and 2-3% in stems at 216 h. The content of (+)-methamidophos was 1.5 times higher than that of (-)-methamidophos in excised leaves. Though both (±)-acephate and (±)-methamidophos could be metabolized well by cell suspension, (±)-acephate and (±)-methamidophos was non-enantioselectively metabolized in cell suspension. It was shown that using the excised tea stem with leaves for chiral pesticide metabolism studies was much closer to intact plant than cell suspensions. This result also established an effective and easily available in vitro metabolic model for the study of enantioselective metabolism of chiral contaminants from environment.


Asunto(s)
Camellia sinensis , Insecticidas , Insecticidas/análisis , Compuestos Organotiofosforados , Fosforamidas , Hojas de la Planta/química , Estereoisomerismo , Suspensiones ,
10.
Pestic Biochem Physiol ; 176: 104861, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34119225

RESUMEN

The stereoselective difference of chiral pesticide enantiomers is an important factor of risk evaluation and the subject has received wide attention. In the present work, enantioselective metabolism of chiral phenylpyrazole insecticides including fipronil, ethiprole and flufiprole in rat liver microsomes was investigated in vitro. The result showed remarkable enantioselectivity for fipronil and ethiprole with the EF values of 0.11-0.58. The metabolite fipronil-sulfone was formed with the degradation of fipronil. R-Ethiprole to S-ethiprole transformation was observed, but not S-ethiprole to R-ethiprole. No enantioselective metabolism was observed for flufiprole with the EF values of 0.49-0.51. The enzymatic assays showed that the inhibition ratio of R-fipronil and S-ethiprole was 1.5-2.1times that of the corresponding enantiomers on CYP2E1 and CYP2D2 activity, leading to the enantioselective metabolism. The result of the homology modeling and molecular docking further revealed that S-fipronil (-7.56 kcal mol-1) and R-ethiprole (-6.45 kcal mol-1) performed better binding with CYP2E1 and CYP2D2, respectively. The results provided useful data for the risk evaluation of chiral phenylpyrazole insecticides on ecological safety and human health.


Asunto(s)
Insecticidas , Animales , Citocromo P-450 CYP2E1 , Insecticidas/toxicidad , Hígado , Simulación del Acoplamiento Molecular , Ratas , Estereoisomerismo
11.
Environ Int ; 143: 105940, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32663714

RESUMEN

Isofenphos-methyl (IFP), a chiral organophosphorus pesticide, is one of the main chemicals used to control underground insects and nematodes. Recently, the use of IFP on vegetables and fruits has been prohibited due to its high toxicity. In this study, we investigated the enantioselective distribution and metabolism of IFP and its metabolites, namely, isofenphos-methyl oxon (IFPO) and isocarbophos oxon (ICPO), in male Sprague Dawley (SD) rats. Forty eight hours (48 h) after exposure, ICPO was the main detectable compound in blood (up to 75%) and urine (up to 77%), and we found that (S)-ICPO was significantly more stable than (R)-ICPO (p < 0.05). Therefore, (S)-ICPO was proposed as a suitable candidate biomarker for the biomonitoring of IFP in human urine and blood. After 48 h exposure, 21.2-41.0%, 4.1-15.1%, and 8.6-18.7% of dosed IFP was detected in the liver of racemic, R and S enantiomer-exposed rats, respectively, and R-IFP and R-IFPO showed a faster degradation (p < 0.05). Our results showed that after one week of consecutive exposure to IFP, ICPO was accumulated in the liver of rats in both racemic and enantiopure groups (no difference between the groups, p > 0.05). We found that cytochrome P450 (CYP) (i.e. CYP2C11, CYP2D2 and CYP3A2 enzymes and carboxylesterases) is responsible for the enantioselective metabolism of IFP in liver. In addition, rats exposed to (S)-IFP exhibited hepatic lipid peroxidation, liver inflammation and hepatic fibrosis. This study provides useful information and a reference for the biomonitoring and risk assessment of IFP and organophosphorus pesticide exposure.


Asunto(s)
Compuestos Organotiofosforados , Plaguicidas , Animales , Compuestos Organotiofosforados/toxicidad , Ratas , Ratas Sprague-Dawley , Estereoisomerismo
12.
J Hazard Mater ; 396: 122756, 2020 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-32353726

RESUMEN

Prothioconazole (PTA) is a novel, broad-spectrum, chiral triazole fungicide that is mainly used to prevent and control the disease of cereal crops. However, the adverse effects of PTA and its major metabolite on nontarget organisms have aroused wide concern. In the present work, the acute toxic of the metabolite prothioconazole-desthio (PTA-desthio), with an LC50 of 1.31 mg L-1, was 3.5-fold more toxic than the parent compound, indicating that the metabolism of PTA in zebrafish was toxic. The stereoselective uptake and metabolism of PTA and PTA-desthio in zebrafish was firstly investigated using LC-MS/MS. Remarkable enantioselectivity was observed: S-PTA and S-PTA-desthio were preferentially uptake with the uptake rate constants of 8.22 and 8.15 d-1 at exposure concentration of 0.5 mg L-1, respectively, and the R-PTA-desthio were preferentially metabolized. PTA-desthio was rapidly formed during the uptake processes. The antioxidant enzyme activities in the zebrafish changed significantly, and these effects were reversible. A metabolic pathway including 13 phase I metabolites and 2 phase II metabolites was firstly proposed. A glucuronic acid conjugate and sulfate conjugate were observed in zebrafish. The results of this work provide information that highlights and can help mitigate the potential toxicity of PTA to the ecological environment and humans health.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Cromatografía Liquida , Humanos , Estrés Oxidativo , Espectrometría de Masas en Tándem , Triazoles/análisis , Triazoles/toxicidad , Contaminantes Químicos del Agua/análisis
13.
J Agric Food Chem ; 68(25): 6802-6810, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32323985

RESUMEN

Fluralaner, a veterinary drug, is a potential chiral isoxazoline insecticide possessing high insecticidal and acaricidal activity. However, there is little information regarding the enantioselective effect of fluralaner. In this work, a promising chiral detection method was established with liquid chromatography-mass spectrometry in agricultural products and animal organs to investigate enantioselective metabolism and bioactivity. The optical rotation and absolute configuration of fluralaner enantiomers were confirmed with S-(+)-fluralaner and R-(-)-fluralaner. The bioactivity assay indicated that S-fluralaner was 33-39 times more active than the R-enantiomer against Chilo suppressalis and Laodelphax striatellus. This finding suggests that the application of pure S-fluralaner instead of racemate in agricultural management could reduce risk. Homology modeling and molecular docking showed that S-fluralaner, with a lower energy of -6.90 kcal/mol, possessed better binding affinity to the γ-aminobutyric acid receptor. The stereoselective metabolism in rat liver microsomes was explored, and slight enantioselectivity was observed with R-fluralaner that was preferentially metabolized. The enantiomer fraction values ranged from 0.43 to 0.49. The results provide reference for residue detection, risk assessment, and the scientific use of fluralaner in agricultural applications.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Insecticidas/química , Insecticidas/farmacología , Isoxazoles/química , Isoxazoles/farmacología , Espectrometría de Masas/métodos , Animales , Insecticidas/metabolismo , Isoxazoles/metabolismo , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Simulación del Acoplamiento Molecular , Mariposas Nocturnas/efectos de los fármacos , Ratas , Estereoisomerismo
14.
J Hazard Mater ; 386: 121951, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-31895998

RESUMEN

To clarify the environmental behaviour and bioactivity of epoxiconazole enantiomers, an integrated assessment has been done. The degradation in soil, water, and river-sediments were studied. The toxicity to Chlorella vulgaris and Daphnia magna was also examined. The bioactivity to plant-pathogens and molecular docking to CYP51 were investigated. The obtained results showed that the half-lives of R,S-(+)- and S,R-(-)-epoxiconazole were 38.8 and 21.2 days in Jiangsu soil, 43.2 and 22.7 days in Jiangxi soil, 29.1 and 21.3 days in Jilin soil, 43.5 and 32.7 days in anaerobic Jilin soil, 12.3 and 10.1 days in river sediments, and 33.2 and 9.3 days in river water, respectively. Maximum EF was 0.36 in Yangzi-river water. No enantioselective degradation was found in sterilized conditions. The EC50 to C. vulgaris after 48 h was 27.78 mg L-1, and 18.93 mg L-1 for R,S-(+)-, and S,R-(-)-epoxiconazole, respectively. The LC50 to D. magna was 4.16 mg L-1, and 8.49 mg L-1 for R,S-(+)-, and S,R-(-)-epoxiconazole, respectively. R,S-(+)-epoxiconazole bioactivity was 1.3-7.25 times higher than S,R-(-)-epoxiconazole. In conclusion, R,S-(+)- has higher bioactivity and higher environmental toxicity. In opposite, S,R-(-)- has lower environmental toxicity and lower bioactivity. R,S-(+)-epoxiconazole use is recommended with lower concentrations, which is appropriate for environment safety.


Asunto(s)
Contaminantes Ambientales/toxicidad , Compuestos Epoxi/toxicidad , Fungicidas Industriales/toxicidad , Sedimentos Geológicos/química , Ríos/química , Suelo/química , Triazoles/toxicidad , Aerobiosis , Anaerobiosis , Animales , Biodegradación Ambiental , Chlorella vulgaris/efectos de los fármacos , Chlorella vulgaris/crecimiento & desarrollo , Sistema Enzimático del Citocromo P-450/química , Daphnia/efectos de los fármacos , Daphnia/crecimiento & desarrollo , Contaminantes Ambientales/análisis , Contaminantes Ambientales/química , Compuestos Epoxi/análisis , Compuestos Epoxi/química , Proteínas Fúngicas/química , Fungicidas Industriales/análisis , Fungicidas Industriales/química , Dosificación Letal Mediana , Simulación del Acoplamiento Molecular , Estereoisomerismo , Pruebas de Toxicidad Aguda , Triazoles/análisis , Triazoles/química
15.
Pest Manag Sci ; 76(1): 343-349, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31207141

RESUMEN

BACKGROUND: The chiral pesticide bitertanol has been widely used in the prevention and treatment of fungal diseases on many crops. However, research on bitertanol at the stereoisomer level has not been reported. Here, we study the stereoselective bioactivity, toxicity, and degradation of this pesticide under laboratory and field conditions. RESULT: (1S,2R)-Bitertanol was the most effective stereoisomer, showing 4.3-314.7 times more potent bioactivity than other stereoisomers against eight target pathogenic fungi. (1S,2R)-Bitertanol showed 10.2 times greater inhibition of Botrytis cinerea spore germination than (1R,2S)-bitertanol. According to the receptor-drug docking results, the distances from the nitrogen atom in the heterocycle of (1S,2R)-, (1R,2S)-, (1R,2R)-, and (1S,2S)-bitertanol to the central Fe + atoms in the ferriporphyrin were 2.5, 3.8, 2.6, and 3.8 Å, respectively. (1S,2S)-Bitertanol was 1.6-2.7 times more toxic than (1R,2R)-bitertanol to Chlorella pyrenoidosa. The half-lives of (1R,2S)-, (1S,2R)-, (1R,2R)-, and (1S,2S)-bitertanol were 3.7, 4.1, 4.1, and 4.8 d, respectively, in tomato. CONCLUSION: The stereoselective bioactivity, toxicity, and degradation for bitertanol were first studied here. (1S,2R)-Bitertanol was a high efficiency and low toxicity stereoisomer. Moreover, the stereoselective bioactivity among all stereoisomers correlated with the binding distances and calculated energy differences between stereoisomers and the target protein. This study also provides a foundation for a systematic evaluation of bitertanol at the stereoisomer level. © 2019 Society of Chemical Industry.


Asunto(s)
Fungicidas Industriales/química , Compuestos de Bifenilo , Chlorella , Estereoisomerismo , Triazoles
16.
J Agric Food Chem ; 67(42): 11591-11597, 2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-31557017

RESUMEN

A simple and eco-friendly dispersive solid-phase extraction method coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the determination of the chiral pesticide tefluthrin in food and environmental samples. The response surface methodology was applied to optimize separation conditions. The elution order of tefluthrin enantiomers was Z-cis-(1S,3S)-(-)-tefluthrin and Z-cis-(1R,3R)-(+)-tefluthrin on a Lux Cellulose-1 chiral column was identified via a polarimeter and vibrating circular dichroism. The average recoveries in five matrices ranged from 76.9 to 107.6%, with intraday relative standard deviations (RSDs) less than 15.6% and interday RSDs less than 12.5% for two enantiomers. The enantioselective degradation was investigated via laboratory incubation experiments. Slightly enantioselective degradation was observed under aerobic conditions; (1S,3S)-tefluthrin degraded preferentially with the enantiomer fraction value of 0.57 at 120 days of incubation. No remarkable enantioselective degradation was observed under anaerobic and sterile conditions. It was the first time that pyrethroid pesticides were determined at the enantiomer levels via UPLC-MS/MS. This novel method was successfully applied for the enantioselective analysis of tefluthrin enantiomers in authentic samples, indicating its efficacy in investigating the environmental stereochemistry of tefluthrin in the food web and environment. It is of crucial importance to improve risk assessment and regulation of chiral pesticides in an agricultural system.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ciclopropanos/química , Hidrocarburos Fluorados/química , Plaguicidas/química , Contaminantes del Suelo/química , Suelo/química , Espectrometría de Masas en Tándem/métodos , Estereoisomerismo
17.
Pestic Biochem Physiol ; 160: 112-118, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31519245

RESUMEN

Chiral triazole fungicides have played a significant role in plant pathogen control. Although their enantiomers often exhibit different bioactivity, the mechanism of the stereoselectivity has not been well studied. The stereoselective bioactivity and mechanisms of prothioconazole and its chiral metabolite against plant pathogenic fungi were investigated. The results indicated that the metabolite exerted more fungicidal activities than the activities of the parent compound. R-Prothioconazole and R-prothioconazole-desthio were 6-262 and 19-954 times more potent against pathogenic fungi than the S-enantiomers, respectively. The R-enantiomers were more effective than in inhibiting the biosynthesis of ergosterol and deoxynivalenol the S-enantiomer. Homology modeling and molecular docking suggested that the R-enantiomers of prothioconazole and prothioconazole-desthio possessed better binding modes than S-enantiomers to CYP51B. Moreover, exposure to prothioconazole and its metabolite enantiomers significantly changed the transcription levels of the CYP51 (CYP 51A, CYP51B, CYP 51C) and Tri (Tri5, Tri6, Tri12) genes. The results showed that application of the R-prothioconazole could require a smaller application amount to eliminate the carcinogenic mycotoxins and any environmental risks.


Asunto(s)
Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Triazoles/farmacología , Fungicidas Industriales/química , Simulación del Acoplamiento Molecular , Estereoisomerismo , Triazoles/química
18.
Environ Pollut ; 251: 30-36, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31071630

RESUMEN

The wide use of chiral fungicides has generated interest in the stereoselectivity of their ecotoxicological effects. However, there are few studies about the potential endocrine-disrupting effects (EDEs) of chiral fungicides. This study evaluated the hormone receptor activities of the chiral triazole fungicide prothioconazole and its metabolite using reporter gene assays. The results indicated that prothioconazole and its metabolite possessed EDEs, and the metabolite exerted more activities than the activities of the parent compound, suggesting that the metabolic process is toxification. Stereoselective EDEs were observed, and the S-enantiomers possessed greater hormonal effects than those possessed by the R-enantiomers; the REC20 values ranged from 7.9 × 10-10 to 6.4 × 10-7 M for the thyroid hormone effects and from 3.2 × 10-9 to 7.8 × 10-8 M for the estrogenic effects. The molecular docking results revealed that the stereoselective EDEs of prothioconazole and its metabolite were partially attributed to enantiospecific receptor binding affinities. Overall, our results reveal that prothioconazole and its metabolite might disrupt the balance of the endocrine system by affecting the function of multiple nuclear hormone receptors and that they have the potential to affect the developmental and reproductive systems in humans.


Asunto(s)
Disruptores Endocrinos/metabolismo , Disruptores Endocrinos/toxicidad , Fungicidas Industriales/metabolismo , Fungicidas Industriales/toxicidad , Triazoles/metabolismo , Triazoles/toxicidad , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Chlorocebus aethiops , Disruptores Endocrinos/química , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Fungicidas Industriales/química , Genes Reporteros , Humanos , Simulación del Acoplamiento Molecular , Estereoisomerismo , Receptores beta de Hormona Tiroidea/genética , Receptores beta de Hormona Tiroidea/metabolismo , Triazoles/química
19.
Environ Int ; 127: 694-703, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30991225

RESUMEN

Isofenphos-methyl (IFP) is a very active and persistent chiral insecticide. However, IFP has lower activity against acetylcholinesterases (AChEs). Previously, it was confirmed that phosphorothioate organophosphorus pesticides with N-alkyl (POPN) require activation by oxidative desulfuration and N-dealkylation. In this work, we demonstrated that IFP could be metabolized in human liver microsomes to isofenphos-methyl oxon (IFPO, 52.7%), isocarbophos (ICP, 14.2%) and isocarbophos oxon (ICPO, 11.2%). It was found that (R)-IFP was preferentially degraded compared to the (S)-enantiomer, and the enantiomeric fraction (EF) value reached 0.61 at 60 min. However, (S)-enantiomers of the three metabolites, were degraded preferentially, and the EF values ranged from 0.34 to 0.45. Cytochrome P450 (CYP) isoforms CYP3A4, CYP2E1, and CYP1A2 and carboxylesterase enzyme have an essential role in the enantioselective metabolism of IFP; but, the enzymes that participate in the degradation of IFP metabolites are different. The AChE inhibition bioassay indicated that ICPO is the only effective inhibitor of AChE. The covalent molecular docking has proposed that the metabolites of IFP and its analogs after N-dealkylation and oxidative desulfuration will possess the highest inhibitory activity against AChE. This study is the first to demonstrate that ICPO can be regarded as a potential biomarker for the biomonitoring of IFP and ICP exposure in humans.


Asunto(s)
Compuestos Organotiofosforados/metabolismo , Biomarcadores/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Citocromo P-450 CYP3A/metabolismo , Humanos , Malatión/análogos & derivados , Microsomas Hepáticos , Simulación del Acoplamiento Molecular , Compuestos Organotiofosforados/química , Estereoisomerismo
20.
Chemosphere ; 224: 77-84, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30818197

RESUMEN

Triazole fungicides with one or two chiral centers are widely used worldwide. The liver microsomes plays a major role in the metabolism and systemic elimination of chiral pesticides after exposure. In this present work, enantioselective metabolism of four representative chiral triazole fungicides (prothioconazole, flutriafol, triticonazole, and epoxiconazole) in rat liver microsomes (RLM) was investigated using LC-MS/MS. Baseline separation of the four chiral fungicides and prothioconazole-desthio was achieved on Lux-cellulose-1. The results demonstrated that the R-enantiomers of flutriafol and triticonazole were preferentially metabolized with half-life ranged from 17.33 min to 99.00 min. The R,S-epoxiconazole accumulated with a half-life of 173.25 min. There was no stereoselectivity for prothioconazole. However, remarkable stereoselective metabolism was observed for prothioconazole-desthio. The results of enzyme kinetic revealed different affinities between the enantiomers and metabolic enzymes. In addition, homologous modeling and molecular docking results indicated that enantioselectivity were partially to enantiospecific binding affinities with CYP enzymes. This study highlights a new quantitative approach for stereoselective metabolism of chiral agrochemicals and provides more accurate data on risk assessment of triazole fungicides.


Asunto(s)
Fungicidas Industriales/metabolismo , Microsomas Hepáticos/metabolismo , Triazoles/metabolismo , Animales , Cromatografía Líquida de Alta Presión/métodos , Ciclopentanos/metabolismo , Compuestos Epoxi/metabolismo , Simulación del Acoplamiento Molecular , Ratas , Estereoisomerismo , Espectrometría de Masas en Tándem/métodos
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