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1.
Food Chem ; 367: 130734, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34359003

RESUMEN

Isocycloseram is a new isoxazoline insecticide that can efficiently control the diamondback moth in cruciferous crops. The aim of this study was to establish a method for the determination of isocycloseram residues in/on cabbage and in the soil using HPLC-UV at 264 nm. A field test was conducted in December 2019 and 2020 to monitor isocycloseram dissipation in Jiangxi, China. Acetonitrile was used to extract isocycloseram from cabbage and soil. C18 and GCB were used to purify cabbage extracts, whereas soil extracts did not require purification. At the addition level of 0.01-1.0 mg/kg, the average recoveries in cabbage and soil were 91.81-109.95% and 89.89-104.08% respectively. After having applied 10% isocycloseram DC, isocycloseram dissipated faster in the cabbage matrix. Isocycloseram residues on cabbage leaves could be removed through simple cleaning methods, especially by soaking in 2% citric acid.


Asunto(s)
Brassica , Residuos de Plaguicidas , Contaminantes del Suelo , Cromatografía Líquida de Alta Presión , Semivida , Residuos de Plaguicidas/análisis , Suelo , Contaminantes del Suelo/análisis
2.
Food Chem ; 367: 130740, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34375891

RESUMEN

Traditional sample preparation methods for insecticide analysis are laborious and fatal to living organisms. In the work, an in vivo sampling rate calibrated-solid phase microextraction-gas chromatography-mass spectrometry method was established and successfully used for in vivo sampling and quantitative determination of three insecticides (hexachlorobenzene, fipronil and chlorfenapyr) by direct exposing micron-sized fiber in living garlic. Absorption, enrichment, migration and elimination behavior of insecticides in garlic were investigated. Bioaccumulative effects with obvious tissue differences were observed to all three insecticides, especially for chlorfenapyr. Bioconcentration factors (BCFs) ranging from 0.0342 to 1.0887 were obtained, and the closer to roots, the higher BCFs. The half-life of insecticides in garlic ranged from 0.43 to 0.96 d. In the first 24 h, 55.0% - 80.3% insecticides residues in garlic were eliminated with first-order elimination kinetics. The research provides in vivo insights into the environmental fates of insecticides in complex living system with minimized organism damage.


Asunto(s)
Ajo , Insecticidas , Residuos de Plaguicidas , Cromatografía de Gases y Espectrometría de Masas , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Microextracción en Fase Sólida
3.
Food Chem ; 367: 130714, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34388632

RESUMEN

The following qualitative screening and quantitative determination of 201 pesticides present a detailed optimization making use of design of experiments (DoE). The post-targeted screening took advantage of an upgradeable database to extend the survey further to perform a standard-free novel quantitation by liquid chromatography high resolution mass spectrometry (LC-HRMS). The fine tuning of instrumental parameters allowed the best method selectivity, sensitivity and reproducibility for the compounds under study. Among the factors considered, the heated electrospray source (HESI), the sample composition and the MS/MS acquisition modes were assessed, including the all-ion fragmentation (AIF) mode and different versions of the variable data independent acquisition (vDIA). The results of the optimization showed that selected HESI conditions, a methanol/water (1:1) sample composition and a vDIA acquisition method increased the signal for most compounds with a remarkable benefit on signal shape and intensity. The method showed adequate analytical performance when assessed in local produce.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Frutas/química , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Verduras
4.
Food Chem ; 367: 130774, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34390913

RESUMEN

Gas-liquid microextraction technique (GLME) has been integrated with dispersive solid phase extraction to establish a one-step sample pretreatment approach for rapid analysis of multi-class pesticides in different plant-derived foods. A 50 µL of organic solvent plus 40 mg of PSA were required throughout the 5-minute pretreatment procedure. Good trueness (recoveries of 67.2 - 105.4%) and precision (RSD ≤ 18.9%) were demonstrated by the one-step GLME method, with MLOQs ranged from 0.001 to 0.011 mg kg-1. As high as 93.6% pesticides experienced low matrix effect through this method, and the overall matrix effects (ME%) were generally better or comparable to QuEChERS. This method successfully quantified 2-phenylphenol, quintozene, bifenthrin and permethrin in the range of 0.001 - 0.008 mg kg-1 in real food samples. The multiresidue analysis feature of GLME has been validated, which displays further potential for on-site determination of organic pollutants in order to safeguard food safety and human health.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Humanos , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Extracción en Fase Sólida , Solventes
5.
Talanta ; 236: 122825, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34635215

RESUMEN

Relative matrix effects between an ambient mass spectrometric technique known as coated blade spray (CBS) and liquid chromatographic separation approach when applied to multiresidue pesticide analysis in strawberry samples are explored. Acceptable slope relative standard deviations (RSD <15 %) were observed for the 9 compounds under study for both CBS-MS/MS (2.2-12.6 %) and LC-MS/MS (2.8-12.9 %) approaches. The findings signify both the elimination of relative matrix effects with the sample preparation and matrix match calibration with internal standard correction methods employed along with no matrix effect compromise made when using the direct-to-MS approach. Similarly, slopes of pesticides spiked from commercially available formulations (containing one or two pesticides) were found to not differ significantly from slopes generated with multiresidue pesticide standards (containing 24 additional pesticides besides the target 9 analytes) with either technique, highlighting the resistance of the employed methods to the excipients present in pesticide formulations in large amounts.


Asunto(s)
Fragaria , Residuos de Plaguicidas , Plaguicidas , Cromatografía Liquida , Excipientes , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem
6.
Artículo en Chino | MEDLINE | ID: mdl-34624949

RESUMEN

Objective: To explore the value of soluble growth stimulation expression gene 2 protein (soluble suppression of tumorigenicity 2; sST2) and N terminal B type brain natriuretic peptide (N-terminal probrainnatriuretic peptide, NT-proBNP) in evaluating the short-term prognosis of acute organophosphorus pesticide poisoning. Methods: select 228 patients with acute organophosphorus pesticide poisoning in our hospital from October 2017 to March 2020. According to the grade of poisoning degree, it was divided into 82 cases in mild and moderate group and 146 cases in severe group. hs-cTnI、CK-MB、sST2、NT-proBNP、APACHE Ⅱ score and cholinesterase activity were detected 4 h、12 h、24 h after admission. ROC curve was used to evaluate sST2 and NT-proBNP to predict the prognosis of AOPP. Results: 4 hours after admission, there was no significant difference in the scores of hs-cTnI, APACHE Ⅱ, cholinesterase and CK-MB between the Severe Group and the mild and moderate Group (P<0.05) . At 12 and 24 hours after admission, the scores of hs-cTnI, CK-MB and APACHE Ⅱ in severe group were higher than those in mild and moderate group, and the changes of Cholinesterase were more significant than those in 12 hours after Admission (P<0.05) . 4 hours after admission, SST2 and NT-proBNP levels were significantly higher in severe group than those in mild and moderate Group (P<0.05) . The level of SST2 and NT-proBNP in the severe group was significantly higher than that in the mild and moderate group 12 and 24 hours after Admission (P<0.01) , and the level of SST2 and NT-proBNP was significantly higher than that in the mild group 12 hours after Admission (P<0.05) . Correlation analysis showed that 24 hours after admission, sST2, NT-proBNP were positively correlated with APACHE-Ⅱ scores (R=0.634, 0.723, P<0.01) . The area under sST2 combined with NT-proBNP was 0.891, higher than that under sST2 and NT-proBNP at 12 h after admission. The 24 h APACHE Ⅱ score after admission area under the curve was 0.838. Conclusion: sST2 and NT-proBNP combined detection can early predict the occurrence of recent complications in AOPP patients.


Asunto(s)
Proteína 1 Similar al Receptor de Interleucina-1 , Péptido Natriurético Encefálico , Plaguicidas , Biomarcadores , Humanos , Compuestos Organofosforados , Fragmentos de Péptidos , Plaguicidas/envenenamiento , Pronóstico
7.
Environ Monit Assess ; 193(10): 689, 2021 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-34601623

RESUMEN

The objective of this study was to evaluate the occurrence of pesticides in surface and groundwater of agricultural areas of the Pampas region of Argentina and to develop an ecological risk assessment (ERA) of pesticides in freshwater ecosystems. Eight agricultural sites from south Santa Fe province, in the north of the Pampas region, were sampled seven times between 2016 and 2018. Pesticides were analysed by gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (UPLC-LC/MS). Twenty compounds among herbicides, insecticides and fungicides in 84% and 79% of groundwater and surface water samples, respectively, were detected. Atrazine was the most ubiquitous pesticide, following by metolachlor, acetochlor and glyphosate, with maximum concentrations of 28, 24, 77 and 111 µg/L, respectively. An ERA was performed by employing the risk quotient (RQ) method. Atrazine, azoxystrobin, pirimiphos-methyl, acetochlor and epoxiconazole posed a high and very high risk for aquatic organisms (RQ > 1) and glyphosate, metolachlor and 2,4-D exhibited negligible to medium risk. The herbicides were the major contributors to risk. This study is the first contribution on the presence and concentration of pesticides in surface and groundwater from agricultural areas of south Santa Fe province, north Pampas region, Argentina, and a starting point for pesticide ecological risk assessment.


Asunto(s)
Agua Subterránea , Plaguicidas , Contaminantes Químicos del Agua , Argentina , Ecosistema , Monitoreo del Ambiente , Plaguicidas/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
8.
Anal Chim Acta ; 1184: 339026, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34625266

RESUMEN

In this work, boron carbon oxynitride quantum dots (BCNO QDs) were prepared by a one-step hydrothermal process of ethanolamine and boric acid. BCNO QDs exhibited blue fluorescence with the optimal excitation/emission fluorescence peak at 335 and 420 nm, respectively. As an efficient fluorescence quencher, manganese dioxide (MnO2) nanosheets can effectively quench the fluorescence of BCNO QDs via the inner filter effect (IFE). Acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylcholine (ATCh) to produce thiocholine (TCh). TCh can reductively degrade MnO2 nanosheets to generate Mn2+, thereby recovering the fluorescence of BCNO QDs. Organophosphorus pesticides (OPs) can inhibit the activity of AChE enzymes, thereby preventing the production of TCh and the decomposition of MnO2 nanosheets, resulting in the fluorescence "turn-off". Therefore, the concentration of OPs can be detected by measuring the fluorescence intensity change of AChE-ATCh-MnO2-BCNO-QDs system. Under optimal experimental conditions, the dynamic detection range of paraoxon is 0.1-250 ng mL-1, and the detection limit is 0.03 ng mL-1. Meanwhile, the reaction system also showed concentration-dependent visual color changes from colorless to brownish. Furthermore, we prepared a portable BCNO QDs test paper. By using a smartphone to identify the RGB values of the reaction solution and the corresponding test paper, we carried out the digital image chromaticity analysis, which can shorten the detection time and reduce the detection cost, and provide an effective solution for the rapid detection of OPs on site.


Asunto(s)
Técnicas Biosensibles , Plaguicidas , Puntos Cuánticos , Acetilcolinesterasa , Boro , Carbono , Colorimetría , Compuestos de Manganeso , Compuestos Organofosforados , Óxidos , Plaguicidas/análisis , Teléfono Inteligente
9.
Anal Chim Acta ; 1178: 338802, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34482881

RESUMEN

Dispersive micro solid-phase extraction procedure using a novel and selective sorbent prepared from four components was developed as a sample preparation strategy for extracting five organophosphorus pesticides, including fenitrothion, malathion, ethion, and chlorpyrifos, and diazinon in several vegetables, fruit juices, and cow's milk samples. Due to the high importance of the sorbent in the microextraction process, the percentages of sorbent components, including metal-organic framework (ZIF-67), chitosan, magnetic Fe3O4 nanoparticles, and silica nanoparticles, were optimized by a simplex lattice mixture design. After optimizing the sorbent composite, effective parameters on the extraction of organophosphorus pesticides were optimized using a definitive screening design and Box-Behnken design, respectively. A surfactant (Triton X100) as a dispersion agent with a low volume (10 µL) was utilized in the microextraction procedure to reduce the sorbent dispersion time and increase the sorbent dispersion efficiency. Under the optimal conditions, linearity for the determination of fenitrothion, malathion, ethion, chlorpyrifos, and diazinon was in the concentration ranges of 0.13-1100, 0.27-1000, 0.38-1000, 0.21-1200, and 0.11-1100 ng mL-1 with a determination coefficient higher than 0.9906, respectively. The quantitation limits, detection limits, and relative standard deviations (n = 5) were lower than 0.38 ng mL-1, 0.11 ng mL-1, and 4.59% for the determination of organophosphorus pesticides. The method application for measuring OPPs on cucumber, carrot, tomato, apple juice, orange juice, and cow's milk indicated the presence of residual amounts of malathion in a cucumber sample, diazinon in a carrot sample, and chlorpyrifos in a tomato sample.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Animales , Jugos de Frutas y Vegetales , Límite de Detección , Fenómenos Magnéticos , Leche/química , Compuestos Organofosforados/análisis , Plaguicidas/análisis , Extracción en Fase Sólida , Verduras , Agua/análisis
10.
Se Pu ; 39(9): 930-940, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34486832

RESUMEN

Polar pesticides can be primarily classified as fungicides, herbicides, and insecticides; their rich variety and low cost have led to their extensive utilization in agriculture. However, the overuse of polar pesticides can lead to environmental contamination, such as water or soil pollution, which can also increase the risk of pesticide exposure among human life directly, or indirectly through contact with animal and plant-derived food. There are considerable differences in the physical and chemical properties of polar pesticides, as well as their trace amounts in complex food and environmental samples, posing immense challenges to their accurate detection. As a kind of artificially prepared selective adsorbent, molecularly imprinted polymers (MIPs) possess specific recognition sites complementary to template molecules in terms of the spatial structure, size, and chemical functional groups. With many advantages such as easy preparation, low cost, as well as good chemical and mechanical stability, MIPs have been widely applied in sample pretreatment and the analysis of polar pesticide residues. MIPs are typically used as adsorption materials in solid phase extraction (SPE) methods, including magnetic solid phase extraction (MSPE), dispersed solid phase extraction (DSPE), and stir bar sorptive extraction (SBSE). To rapidly detect polar pesticide residues with high sensitivity, MIPs are also used in the preparation of fluorescent sensors and electrochemical sensors. Furthermore, MIPs can be employed as the substrate in surface-enhanced Raman spectroscopy and as the substrate for the ion source in mass spectrometry for polar pesticide residue analysis. Thus far, various molecularly imprinted materials have been reported for the efficient separation and analysis of polar pesticide residues in various complex matrices. However, there is no review that summarizes the recent advances in MIPs for the determination of polar pesticides. This review introduces imprinting strategies and polymerization methods for MIPs, and briefly summarizes some new molecular imprinting strategies and preparation technologies. The application of MIPs in recent years (particularly the last five years) to the detection of polar pesticide residues including neonicotinoids, organophosphorus, triazines, azoles, and urea is then systematically summarized. Finally, the future development direction and trends for MIPs are proposed considering existing challenges, with the aim of providing reference to guide future research on MIPs in the field of polar pesticide residue detection.


Asunto(s)
Impresión Molecular , Residuos de Plaguicidas , Plaguicidas , Adsorción , Humanos , Polímeros Impresos Molecularmente , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Extracción en Fase Sólida
11.
Se Pu ; 39(9): 958-967, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34486835

RESUMEN

Dried fruit foods, including nuts and preserved fruits, are favored by consumers and are rich in protein, lipids, minerals, vitamins, and other nutrients. However, these food products can be contaminated by pesticide residues, heavy metals, mycotoxins, and additives during growth, processing, storage, and transportation. The presence of such pollutants in excess of a certain limit will lead to food safety problems. Therefore, it is of great economic and social significance to strengthen the quality supervision of dried fruit foods. However, these foods have a complex matrix and low concentrations of various harmful substances, which necessitates efficient and appropriate sample preparation methods as well as rapid, accurate detection methods. In the present article, the sample preparation and analytical methods for harmful substances in dried fruit foods since 2010 are reviewed. The sample preparation methods are classified as field-assisted extraction, phase separation, and derivatization and extraction methods. The field-assisted extraction method is based on the action of an external field (synergistic) such as ultrasonic or microwave fields to increase the dissolution rate of hazardous substances in dried fruits and improve the extraction efficiency. Phase separation methods such as solid-phase extraction, dispersive solid-phase extraction and solid-phase microextraction are commonly used as sample preparation methods for dried fruit samples, because of the advantages of low solvent consumption and wide analysis range. Moreover, this paper discusses the progress of various analytical methods for these hazardous substances in dried fruits, including conventional laboratory methods such as chromatography, atomic spectroscopy, inorganic mass spectrometry, and electrochemical analysis, as well as rapid detection techniques suitable for field analysis. Laboratory testing has the advantages of high accuracy, high sensitivity, and low detection limits. However, it has the disadvantages of complicated preparation, long analysis time, and difficult operation. Rapid detection technology speeds up the analytical speed, has operational simplicity, and saves analysis time. The complexity of the food matrix, which easily interferes with the sample matrix, low selectivity, and difficulty in accurate quantification, it is necessary to minimize cases of incorrect or erroneous detection. Therefore, rapid detection of harmful substances in dried fruit foods is possible by optimizing the sample pretreatment methods and detection technologies, and by seeking new (especially, on-site) detection technologies. Prospects on the development of selective and non-destructive sample preparation methods and automated, high-throughput, rapid detection methods in dried fruit food analysis are presented. The development of new, green rapid sample pretreatment methods and technical products that integrate separation, enrichment, and detection as well as the construction of accurate and sensitive rapid detection methods are expected to become the development trend in the analysis of harmful substances in dried fruit foods.


Asunto(s)
Frutas , Residuos de Plaguicidas , Análisis de los Alimentos , Frutas/química , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida , Microextracción en Fase Sólida
12.
Braz J Biol ; 83: e248842, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34495166

RESUMEN

Acetylcholinesterase (AChE) activity levels can be used as an indicator for AChE inhibition due to pesticide poisoning in bird species. We assessed the comparative brain cholinesterase (AChE) activity level of five bird species inhabiting pesticide exposed croplands and Protected Area i.e. Deva Vatala National Park (DVNP), Bhimber by using a spectrophotometric method. AChE activity levels ranged from 56.3 to 85.9 µmol/min/g of brain tissue of birds representing DVNP. However, AChE activity levels ranged from 27.6 to 79.9 µmol/min/g of brain tissue of birds representing croplands. AChE activity levels observed in Jungle babbler, Common babbler, and Red-vented bulbul showed significant differences (P < 0.05) at two sites. However, White wagtail and Black drongo demonstrated non-significant differences (P > 0.05). Maximum inhibition was recorded in Jungle babbler (53%) followed by Common babbler (35%), Red-vented bulbul (18%), White wagtail (15%), and Black drongo (7%). The brain cholinesterase inhibition levels under-protected ecosystems (DVNP, Bhimber) and agricultural landscape suggest insecticidal contamination and its impact on avifauna diversity. The study also emphasizes on the importance of pesticide-free zones to protect the biodiversity of birds.


Asunto(s)
Plaguicidas , Acetilcolinesterasa , Animales , Aves , Inhibidores de la Colinesterasa/toxicidad , Productos Agrícolas , Ecosistema , Pakistán , Plaguicidas/toxicidad
13.
Chemosphere ; 283: 131447, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34467951

RESUMEN

Chlorpyrifos (CPF) falls under the category of organophosphorus pesticides which are in huge demand in the agricultural sector. Overuse of this pesticide has led to the degradation of the quality of terrestrial and aquatic life. The chemical is moderately persistent in the environment but its primary metabolite 3,5,6-trichloro-2-pyridinol (TCP) is comparatively highly persistent. Thus, it is important to degrade the chemical and there are many proposed techniques of degradation. Out of which bioremediation is considered to be highly cost-effective and efficient. Many previous studies have attempted to isolate appropriate microbial strains to degrade CPF which established the fact that chlorine atoms released while mineralising TCP inhibits further proliferation of microorganisms. Thus, it has been increasingly important to experiment with strains that can simultaneously degrade both CPF and TCP. In this review paper, the need for degrading CPF specifically the problems related to it has been discussed elaborately. Alongside these, the metabolism pathways undertaken by different kinds of microorganisms have been included. This paper also gives a detailed insight into the potential strains of microorganisms which has been confirmed through experiments conducted previously. It can be concluded that a wide range of microorganisms has to be studied to understand the possibility of applying bioremediation in wastewater treatment to remove pesticide residues. In addition to this, in the case of recalcitrant pesticides, options of treating it with hybrid techniques like bioremediation clubbed with photocatalytic biodegradation can be attempted.


Asunto(s)
Cloropirifos , Insecticidas , Plaguicidas , Compuestos Organofosforados , Piridonas
14.
Chemosphere ; 283: 131125, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34467953

RESUMEN

Persistent organic pollutants (POPs) are industrial chemicals with long half-lives. Early life exposure to POPs has been associated with adverse effects. Fetal exposure is typically estimated based on concentrations in maternal serum or placenta and little is known on the actual fetal exposure. We measured the concentrations of nine organochlorine pesticides (OCPs), ten polychlorinated biphenyl (PCB) congeners, and polybrominated diphenyl ether (PBDE) congeners by gas chromatography - tandem mass spectrometry in maternal serum, placenta, and fetal tissues (adipose tissue, liver, heart, lung and brain) in 20 pregnancies that ended in stillbirth (gestational weeks 36-41). The data were combined with our earlier data on perfluoroalkyl substances (PFASs) in the same cohort (Mamsen et al. 2019). HCB, p,p'-DDE, PCB 138 and PCB 153 were quantified in all samples of maternal serum, placenta and fetal tissues. All 22 POPs were detected in all fetal adipose tissue samples, even in cases where they could not be detected in maternal serum or placenta. Tissue:serum ratios were significantly higher in later gestations, male fetuses, and pregnancies with normal placental function. OCPs showed the highest tissue:serum ratios and PFAS the lowest. The highest chemical burden was found in adipose tissue and lowest in the brain. Overall, all studied human fetuses were intrinsically exposed to mixtures of POPs. Tissue:serum ratios were significantly modified by gestational age, fetal sex and placental function. Importantly, more chemicals were detected in fetal tissues compared to maternal serum and placenta, implying that these proxy samples may provide a misleading picture of actual fetal exposures.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Femenino , Feto , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Exposición Materna , Contaminantes Orgánicos Persistentes , Placenta , Embarazo
15.
BMC Genomics ; 22(1): 639, 2021 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-34479486

RESUMEN

BACKGROUND: Resistance of pest insect species to insecticides, including B. thuringiensis (Bt) pesticidal proteins expressed by transgenic plants, is a threat to global food security. Despite the western corn rootworm, Diabrotica virgifera virgifera, being a major pest of maize and having populations showing increasing levels of resistance to hybrids expressing Bt pesticidal proteins, the cell mechanisms leading to mortality are not fully understood. RESULTS: Twenty unique RNA-seq libraries from the Bt susceptible D. v. virgifera inbred line Ped12, representing all growth stages and a range of different adult and larval exposures, were assembled into a reference transcriptome. Ten-day exposures of Ped12 larvae to transgenic Bt Cry3Bb1 and Gpp34/Tpp35Ab1 maize roots showed significant differential expression of 1055 and 1374 transcripts, respectively, compared to cohorts on non-Bt maize. Among these, 696 were differentially expressed in both Cry3Bb1 and Gpp34/Tpp35Ab1 maize exposures. Differentially-expressed transcripts encoded protein domains putatively involved in detoxification, metabolism, binding, and transport, were, in part, shared among transcripts that changed significantly following exposures to the entomopathogens Heterorhabditis bacteriophora and Metarhizium anisopliae. Differentially expressed transcripts in common between Bt and entomopathogen treatments encode proteins in general stress response pathways, including putative Bt binding receptors from the ATP binding cassette transporter superfamily. Putative caspases, pro- and anti-apoptotic factors, as well as endoplasmic reticulum (ER) stress-response factors were identified among transcripts uniquely up-regulated following exposure to either Bt protein. CONCLUSIONS: Our study suggests that the up-regulation of genes involved in ER stress management and apoptotic progression may be important in determining cell fate following exposure of susceptible D. v. virgifera larvae to Bt maize roots. This study provides novel insights into insect response to Bt intoxication, and a possible framework for future investigations of resistance mechanisms.


Asunto(s)
Bacillus thuringiensis , Escarabajos , Plaguicidas , Animales , Bacillus thuringiensis/genética , Supervivencia Celular , Escarabajos/genética , Endotoxinas/toxicidad , Resistencia a los Insecticidas , Larva/genética , Control Biológico de Vectores , Plantas Modificadas Genéticamente/genética , Regulación hacia Arriba , Zea mays/genética
16.
J Hazard Mater ; 416: 125911, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492845

RESUMEN

Plant growth can be influenced by the application of triazole pesticides as these regulate physiological processes such as plant hormonal levels and enzyme activity. Homology modeling and molecular docking studies suggested that inhibition of ADP-glucose pyrophosphorylase activity in two trans-stereoisomers treatments hinders starch accumulation during the grain filling stage. A field experiment investigated the effects of metconazole racemate, cis-1R,5S-stereostereoisomer, and cis-1S,5R-stereoisomer application at the flowering stage on wheat grain ripening and yield. The concentrations of racemate and both cis-stereoisomers were detected in wheat plant and grain samples. Compared with the racemate, both cis-stereoisomers were more persistent in the matrices. Treatment with cis-1R,5S-stereoisomer decreased grain weight and yield of wheat by delaying chlorophyll degradation, increasing the ethylene content, and decreasing the level of abscisic acid. The germination of harvested seeds was adversely affected by racemate treatment as a result of gibberellin and abscisic acid metabolism regulation and the transcription of signaling-related genes. Therefore, cis-1S,5R-stereoisomer was recommended to be used as metconazole pesticide at the flowering stage.


Asunto(s)
Plaguicidas , Triticum , Germinación , Simulación del Acoplamiento Molecular , Semillas , Triazoles
17.
J Hazard Mater ; 416: 125912, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492846

RESUMEN

Emerging contaminants (ECs) in wastewater have recently attracted the attention of researchers as they pose significant risks to human health and wildlife. This paper presents the state-of-art technologies used to remove ECs from wastewater through a comprehensive review. It also highlights the challenges faced by existing EC removal technologies in wastewater treatment plants and provides future research directions. Many treatment technologies like biological, chemical, and physical approaches have been advanced for removing various ECs. However, currently, no individual technology can effectively remove ECs, whereas hybrid systems have often been found to be more efficient. A hybrid technique of ozonation accompanied by activated carbon was found significantly effective in removing some ECs, particularly pharmaceuticals and pesticides. Despite the lack of extensive research, nanotechnology may be a promising approach as nanomaterial incorporated technologies have shown potential in removing different contaminants from wastewater. Nevertheless, most existing technologies are highly energy and resource-intensive as well as costly to maintain and operate. Besides, most proposed advanced treatment technologies are yet to be evaluated for large-scale practicality. Complemented with techno-economic feasibility studies of the treatment techniques, comprehensive research and development are therefore necessary to achieve a full and effective removal of ECs by wastewater treatment plants.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Eliminación de Residuos Líquidos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
18.
J Hazard Mater ; 416: 125956, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492873

RESUMEN

Exposure to a single organochlorine pesticide (OCP) at high concentration and over a short period of exposure constrain our understanding of the contribution of chemical exposure to type 2 diabetes (T2D). A total of 450 male and female zebrafish was exposed to mixtures of five OCPs at 0, 0.05, 0.25, 2.5, and 25 µg/L for 12 weeks. T2D-related hematological parameters (i.e., glucose, insulin, free fatty acid, and triglycerides) and mitochondrial complex I to IV activities were assessed. Metabolomics, proteomics, and transcriptomics were analyzed in female livers, and their data-driven integration was performed. High fasting glucose and low insulin levels were observed only at 0.05 µg/L of the OCP mixture in females, indicating a nonlinear and sexually dependent response. We found that exposure to the OCP mixture inhibited the activities of mitochondrial complexes, especially III and IV. Combining individual and integrated omics analysis, T2D-linked metabolic pathways that regulate mitochondrial function, insulin signaling, and energy homeostasis were altered by the OCP mixture, which explains the observed phenotypic hematological effects. We demonstrated the cause-and-effect relationship between exposures to OCP mixture and T2D using zebrafish model. This study gives an insight into mechanistic research of metabolic diseases caused by chemical exposure using zebrafish.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hidrocarburos Clorados , Plaguicidas , Animales , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/genética , Femenino , Insulina , Masculino , Plaguicidas/análisis , Plaguicidas/toxicidad , Pez Cebra
19.
Sensors (Basel) ; 21(17)2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34502694

RESUMEN

This study presents the experimental testing of a gas-sensing array, for the detection of two commercially available pesticides (i.e., Chloract 48 EC and Nimrod), towards its eventual use along a commercial smart-farming system. The array is comprised of four distinctive sensing devices based on nanoparticles, each functionalized with a different gas-absorbing polymeric layer. As discussed herein, the sensing array is able to identify as well as quantify three gas-analytes, two pesticide solutions, and relative humidity, which acts as a reference analyte. All of the evaluation experiments were conducted in close to real-life conditions; specifically, the sensors response towards the three analytes was tested in three relative humidity backgrounds while the effect of temperature was also considered. The unique response patterns generated after the exposure of the sensing-array to the two gas-analytes were analyzed using the common statistical analysis tool Principal Component Analysis (PCA). The sensing array, being compact, low-cost, and highly sensitive, can be easily integrated with pre-existing crop-monitoring solutions. Given that there are limited reports for effective pesticide gas-sensing solutions, the proposed gas-sensing technology would significantly upgrade the added-value of the integrated system, providing it with unique advantages.


Asunto(s)
Nanopartículas , Plaguicidas , Polímeros , Temperatura
20.
Se Pu ; 39(10): 1111-1117, 2021 Oct.
Artículo en Chino | MEDLINE | ID: mdl-34505433

RESUMEN

Tea is one of the most popular beverages worldwide, and its quality is often affected by the excessive pesticide residues during production. During the detection of pesticide residues in tea by chromatography-mass spectrometry and other methods, a strong matrix effect attributed to tea polyphenols and pigments is observed, which seriously impacts the analysis results. In this study, Fe3O4 magnetic nanoparticles and boric acid-functionalized metal organic framework (BA-MOF) materials were combined to prepare a highly efficient adsorbent Fe3O4@BA-MOF for capturing tea polyphenols and pigments. An effective analysis method for pesticide residues in tea samples in combination with gas chromatography-mass spectrometry was established. The introduction of boronic acid ligands into the metal organic framework, as the recognition site of cis-diols, enhanced the polyphenol capture ability. Adsorption of the pigment in the matrix was achieved through π-π interactions between the MOF ligand and the pigment. This new material has significant advantages such as rapid magnetic separation, large surface area, and abundant functional sites. Fe3O4@BA-MOF was prepared by employing simple conditions and characterized by Fouriertransform infrared spectroscopy, scanning electron microscopy, and X-ray diffractometry to identify its functional groups and morphology. After investigating the adsorption effect of different doses of Fe3O4@BA-MOF adsorbents (5, 10, 30, 50, and 80 mg) on tea polyphenols, 50 mg of the adsorbent was added to the tea matrix and shaken thoroughly. The tea polyphenol content in the matrix solution was determined using an ultraviolet spectrophotometer. The polyphenols were reduced by 74.58% within 5 min. The effect of solution pH (2.0, 4.0, 6.0, and 7.0) on the adsorption efficiency was investigated, and pH 7.0 was chosen as the optimal condition. By adjusting the pH of the solution, Fe3O4@BA-MOF could be recycled, and it maintained the excellent adsorption performance after four cycles of use. The introduction of Fe3O4 magnetic nanoparticles led to rapid magnetic response characteristics during sample pretreatment and improved the pretreatment efficiency. In the actual application of tea pesticide detection, after Fe3O4@BA-MOF pretreatment, the average recovery rates of the ten pesticides were in the range of 75.8%-138.6%, and the RSD was in the range of 0.5%-18.7% (n=3). The Fe3O4@BA-MOF nanocomposite prepared by introducing the boric acid ligand into the MOF structure and incorporating Fe3O4 magnetic nanoparticles could specifically adsorb the tea polyphenol matrix. When applied to the detection of pesticide residues in tea, it purifies the matrix and improves the detection efficiency, thus being suitable for the detection and analysis of pesticides in tea.


Asunto(s)
Estructuras Metalorgánicas , Residuos de Plaguicidas , Adsorción , Ácidos Bóricos , Fenómenos Magnéticos , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida ,
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