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1.
Environ Pollut ; 276: 116716, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33592440

RESUMO

Production of minor crop varieties often requires intensive pesticide use, which raises serious concerns over food safety and human health. Chaenomeles speciosa (Sweet) Nakai as one of the representative of this kind of crops is therefore used for investigating the residue behavior of fenpropathrin and emamectin benzoate, a synthetic pyrethroid and macrocyclic lactone widely used as an insecticide, respectively, from cultivation to C. speciosa postharvest processing. Results showed that the degradation trends of those selected insecticides in C. speciosa followed first-order kinetics with an average half-life (t1/2) of 3.7-4.1 days and a dissipation rate of 97% over 14 days. The terminal residues of fenpropathrin and emamectin benzoate at 120 and 3 g a.i./ha were below the U.S Environmental Protection Agency (FAD, 1.00 mg/kg) and European Union (EU, 0.01 mg/kg) maximum residue limits (MRLs) in papaya species, respectively, when measured 14 days after the final application, which suggested that the use of these insecticides was safe for humans. Postharvest processing procedure resulted in a |90% reduction of the insecticides. Moreover, the hazard quotient (HQ) for C. speciosa decoction (with processing factors) indicated an acceptable risk for human consumption. These findings provide the scientific evidence of reasonable application and risk assessment of the selected pesticide residues in C. speciosa.

2.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Praguicidas/farmacologia , Rosaceae/química , Bactérias/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Compostos Organotiofosforados/metabolismo , Compostos Organotiofosforados/farmacologia , Praguicidas/química , Praguicidas/metabolismo , Rosaceae/metabolismo , Tiametoxam/metabolismo , Tiametoxam/farmacologia
3.
Chemosphere ; 231: 538-545, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31151014

RESUMO

Problems with pesticide residues in medicinal and edible plant have received great attention. The dietary exposure risk induced by presence of pesticide residues depends on its release from the food matrix, i.e., its bioaccessibility. The bioaccessibility of pesticide residues in human food is poorly understood and thus, we used in vitro digestive method to measure the bioaccessibility of six pesticides in Chaenomelis speciosa. Results showed that the lower and upper boundary bioaccessibility values of the six pesticides in C. speciosa was 4.26 and 86.52%, and the bioaccessibility varied for the pesticide types and digestion phase. The α-amylase and pancreatin play an important role in vitro bioaccessibility. Our findings suggest that risk assessment studies should be taken into account the pesticide metabolism, and that previous studies may have underestimated pesticide bioaccessibility.


Assuntos
Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Rosaceae/fisiologia , Disponibilidade Biológica , Humanos , Técnicas In Vitro , Resíduos de Praguicidas/química , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Medição de Risco
4.
Artigo em Inglês | MEDLINE | ID: mdl-31234355

RESUMO

Before being administered as medicinal products, Chinese herbal medicines (CHMs) must be processed and decocted for human consumption. While the presence of pesticide residues in CHMs is a major concern, pesticide dissipation behavior during CHM processing has rarely been reported. In this study, the dissipation of three pesticide residues in the CHM Paeoniae Radix Alba (PRA) was investigated during each step of industrial processing. The boiling process was found to significantly reduce pesticide residues (61-89%), and the peeling process also contributed to pesticide degradation (29-68%). The high temperature (60 °C) during the drying process led to further pesticide degradation. The processing factors of all three pesticides after each processing step were less than one, and the processing factors for the overall process were lower than 0.027, indicating that industrial processing clearly reduced the amount of pesticide residues (97.3-99.4%). The findings provide guidance for the safe use of fungicides in CHMs and can help establish maximum residue limits for PRA to reduce human exposure to pesticides.


Assuntos
Medicamentos de Ervas Chinesas/química , Fungicidas Industriais/química , Paeonia/química , Indústria Química , Temperatura Alta , Humanos , Resíduos de Praguicidas/análise
5.
Food Funct ; 10(1): 289-295, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30566153

RESUMO

Humans are frequently exposed to the residues of various neonicotinoids, highlighting the need to understand human exposure through oral ingestion of contaminated foods. In this study, the effects of different food matrices (tomato, cucumber, and carrot) and their interaction with dietary component additives, including proteins and dietary fiber, was investigated. The results showed that the presence of a food matrix had a significant effect on the bioaccessibility of neonicotinoids (imidacloprid, thiamethoxam, acetamiprid, and thiacloprid) in both the gastric and intestinal environments. Neonicotinoids in tomato presented relatively low bioaccessibility, indicating that the daily intake of the tomato can be regarded as being relatively safer. Moreover, the addition of protein or dietary fiber to fruit and vegetables had a marked influence on neonicotinoid bioaccessibility and the effects varied between the different matrices. In particular, the addition of 2.0% dietary fiber significantly reduced the bioaccessibility (18.38-67.91%). Therefore, we recommend that consuming an increased intake of dietary fiber could improve the safety of fruit and vegetables in daily life. The present results can support the identification of suitable food intake conditions for the significant reduction of pesticide residue levels.


Assuntos
Frutas/química , Resíduos de Praguicidas/química , Verduras/química , Cucumis sativus/química , Cucumis sativus/metabolismo , Daucus carota/química , Daucus carota/metabolismo , Digestão , Contaminação de Alimentos/análise , Frutas/metabolismo , Humanos , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Neonicotinoides/metabolismo , Resíduos de Praguicidas/metabolismo , Verduras/metabolismo
6.
PeerJ ; 6: e5693, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479882

RESUMO

Background: In our previous study, Melaleuca alternifolia essential oil (EO) was considered to have an insecticidal effect by acting on the mitochondrial respiratory chain in insects. However, the mode of action is not fully understood. Methods: In this study, we investigated the insecticidal efficacy of the M. alternifolia EO against another major stored-product pest, Tribolium confusum Jacquelin du Val. Rarefaction and vacuolization of the mitochondrial matrix were evident in oil-fumigated T. confusum adults. Results: Alterations to the mitochondria confirmed the insecticidal effect of the M. alternifolia EO. Furthermore, comparative transcriptome analysis of T. confusum using RNA-seq indicated that most of the differentially expressed genes were involved in insecticide detoxification and mitochondrial function. The biochemical analysis showed that the intracellular NAD+/NADH ratio is involved in the differential effect of the M. alternifolia EO. Discussion: These results led us to conclude that NAD+/NADH dehydrogenase may be the prime target site for the M. alternifolia EO in insects, leading to blocking of the mitochondrial respiratory chain.

7.
J Pharm Biomed Anal ; 161: 20-27, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30142493

RESUMO

In Traditional Chinese Medicine (TCM), crude herbs are processed to obtain the medicinal parts of the plant, from which extracts are prepared for people to take as medicine. However, there is no report on the pesticide residual behavior in Chinese medicines during processing at present, and thus, a systematic study of the effects of different processing factors (PF) on pesticide removal in Chinese medicines and the associated risk of dietary exposure is urgently needed. This study main investigated the dissipation and metabolism of pesticides in Chinese medicine Paeoniae Radix Alba during processing, and the calculated pesticide PFs were also used to assess the risk of dietary exposure. For analyze samples, a simple and high-throughput multiresidue pesticide analysis method was developed and validated for pesticides and their metabolites in P. Radix. based on QuEChERS procedure combined with HPLC-MS/MS. Recoveries at three concentration levels were within 61.37%-117.82% with an associated precision RSD < 15% indicating satisfactory accuracy. TCM processing could be useful for the partial removal of several pesticide residues, with removal rate reaching 98%. The polarity is the dominant variable, which with a high contribution was the effectiveness of the treatment and the concentration factors for pesticides. The hazard quotients of all pesticides were much lower than the safety level, indicating low risk of dietary exposure. Results are of great theoretical and practical value for the scientific evaluation of the safety of Chinese medicines, improvement of the quality and safety level of Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Paeonia/metabolismo , Praguicidas/farmacocinética , Cromatografia Líquida de Alta Pressão , Substâncias Perigosas/análise , Espectrometria de Massas em Tandem
8.
Artigo em Inglês | MEDLINE | ID: mdl-29762491

RESUMO

Estimating the influence of bioaccessibility of pesticide residues in fruits and vegetables on dietary exposure is a challenge for human health risk assessment. This study investigated the bioaccessibility of pesticide residues in cherry tomatoes and contributing factors (digestion time, pH, solid/liquid ratio, and dietary nutrition) using an in vitro test simulating the human gastrointestinal tract. pH had the largest effect on triazolone precipitation in the simulated gastric intestinal juice, which had a significant impact on the bioaccessibility. The bioaccessibility of triazolone in the intestinal stage was slightly higher than that in the stomach stage, owing to bile salts and pancreatic enzymes present in the intestinal juice. The bioaccessibility of triazolone did not change significantly with digestion time. In the gastric stage, there was a logarithmic relationship between the bioaccessibility and solid/liquid ratio (R² = 0.9941). The addition of oil significantly changed the bioaccessibility in the gastrointestinal stage. Protein and dietary fiber only affected bioaccessibility in the stomach stage. Dietary nutrition can reduce the release of pesticides from fruits and vegetables into the stomach, sharply reducing the bioaccessibility, and the dietary exposure of pesticide residues in fruits and vegetables can be properly evaluated.


Assuntos
Disponibilidade Biológica , Trato Gastrointestinal/metabolismo , Lycopersicon esculentum/química , Modelos Biológicos , Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Humanos , Estado Nutricional , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/isolamento & purificação , Medição de Risco
9.
Molecules ; 23(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596356

RESUMO

In order to ensure raw consumption safety the dissipation behavior, migration, postharvest processing, and dietary risk assessment of five pyrethroids in mushroom (Auricularia polytricha Mont.) cultivated under Chinese greenhouse-field conditions. Half-lives (t1/2) of pyrethroids in fruiting body and substrate samples were 3.10-5.26 and 17.46-40.06 d, respectively. Fenpropathrin dissipated rapidly in fruiting bodies (t1/2 3.10 d); bifenthrin had the longest t1/2. At harvest, pyrethroid residues in A. polytricha (except fenpropathrin) were above the respective maximum residue limits (MRLs). Some migration of lambda-cyhalothrin was observed in the substrate-fruit body system. In postharvest-processing, sun-drying and soaking reduced pyrethroid residues by 25-83%. We therefore recommend that consumers soak these mushrooms in 0.5% NaHCO3 at 50 °C for 90 min. Pyrethroids exhibit a particularly low PF value of 0.08-0.13%, resulting in a negligible exposure risk upon mushroom consumption. This study provides guidance for the safe application of pyrethroids to edible fungi, and for the establishment of MRLs in mushrooms to reduce pesticide exposure in humans.


Assuntos
Basidiomycota , Análise de Alimentos , Piretrinas , Basidiomycota/química , Basidiomycota/metabolismo , Piretrinas/análise , Piretrinas/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-28973970

RESUMO

The transfer of pesticide residues from herbal teas to their infusion is a subject of particular interest. In this study, a multi-residue analytical method for the determination of pyrethroids (fenpropathrin, beta-cypermethrin, lambda-cyhalothrin, and fenvalerate) in honeysuckle, chrysanthemum, wolfberry, and licorice and their infusion samples was validated. The transfer of pyrethroid residues from tea to infusion was investigated at different water temperatures, tea/water ratios, and infusion intervals/times. The results show that low amounts (0-6.70%) of pyrethroids were transferred under the different tea brewing conditions examined, indicating that the infusion process reduced the pyrethroid content in the extracted liquid by over 90%. Similar results were obtained for the different tea varieties, and pesticides with high water solubility and low octanol-water partition coefficients (log Kow) exhibited high transfer rates. Moreover, the estimated values of the exposure risk to the pyrethroids were in the range of 0.0022-0.33, indicating that the daily intake of the four pyrethroid residues from herbal tea can be regarded as safe. The present results can support the identification of suitable tea brewing conditions for significantly reducing the pesticide residue levels in the infusion.


Assuntos
Resíduos de Praguicidas/química , Praguicidas/química , Piretrinas/química , Chás de Ervas/análise , Solubilidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-28885583

RESUMO

The migration and accumulation of octachlorodipropyl ether (OCDPE) in soil-tea systems were investigated using a gas chromatography-electron capture detector (GC-ECD) method in young and old tea gardens. When the residual concentration of OCDPE was 100 g a.i. hm-2 in soils, the peak concentrations of OCDPE in fresh leaves of young and old tea plants were 0.365 mg/kg and 0.144 mg/kg, taking 45 days and 55 days, respectively. Equations for the accumulation curves of OCDPE in fresh leaves of young and old tea plants were Ct = 0.0227e0.0566t (R² = 0.9154) and Ct = 0.0298e-0.0306t (R² = 0.7156), and were Ct = 3.8435e0.055t (R² = 0.9698) and Ct = 1.5627e-0.048t (R² = 0.9634) for dissipation curves, with a half-life of 14.4 days and 12.6 days, respectively. These results have practical guiding significance for controlling tea food safety.


Assuntos
Camellia sinensis/metabolismo , Éteres/análise , Sinergistas de Praguicidas/análise , Folhas de Planta/metabolismo , Poluentes do Solo/análise , Cromatografia Gasosa , Monitoramento Ambiental , Éteres/metabolismo , Inocuidade dos Alimentos , Jardins , Meia-Vida , Sinergistas de Praguicidas/metabolismo , Poluentes do Solo/metabolismo
12.
J Agric Food Chem ; 65(41): 9139-9146, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28915046

RESUMO

This study examined how gastrointestinal conditions affect pesticide bioaccessibility and intestinal transepithelial transport of pesticides (difenoconazole, hexaconazole, and spirodiclofen) in humans. We used an in vitro model combining human gastric and intestinal digestion, followed with Caco-2 cell model for human intestinal absorption. Bioaccessibility of three tested pesticides ranged from 25.2 to 76.3% and 10.6 to 79.63% in the gastric and intestinal phases, respectively. A marked trend similar to the normal distribution was observed between bioaccessibility and pH, with highest values observed at pH 2.12 in gastric juice. No significant differences were observed with increasing digestion time; however, a significant negative correlation was observed with the solid-liquid (S/L) ratio, following a logarithmic equation. R2 ranged from 0.9198 to 0.9848 and 0.9526 to 0.9951 in the simulated gastric and intestinal juices, respectively, suggesting that the S/L ratio is also a major factor affecting bioaccessibility. Moreover, significant dose- and time-response effects were subsequently observed for intestinal membrane permeability of difenoconazole, but not for hexaconazole or spirodiclofen. This is the first study to demonstrate the uptake of pesticides by human intestinal cells, aiding quantification of the likely effects on human health and highlighting the importance of considering bioaccessibility in studies of dietary exposure to pesticide residues.


Assuntos
4-Butirolactona/análogos & derivados , Dioxolanos/metabolismo , Resíduos de Praguicidas/metabolismo , Compostos de Espiro/metabolismo , Triazóis/metabolismo , 4-Butirolactona/química , 4-Butirolactona/metabolismo , Transporte Biológico , Células CACO-2 , Permeabilidade da Membrana Celular , Digestão , Dioxolanos/química , Humanos , Mucosa Intestinal/metabolismo , Intestinos/química , Cinética , Resíduos de Praguicidas/química , Compostos de Espiro/química , Triazóis/química
13.
Chemosphere ; 182: 517-524, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28521167

RESUMO

Bioaccessibility is a crucial parameter in assessing the absorption of contaminants during the human digestive process, but few studies have involved the differences in the bioaccessibilities of pesticides. To investigate the mode of using the in vitro bioaccessibility to refine estimates of dietary exposure to pesticide residues, this study measured the bioaccessibilities of five pyrethroids in apples, and then, it modelled physicochemical predictors (gastrointestinal pH, digestive times, and the solid-liquid (S/L) ratio) of the bioaccessibilities of pyrethroids. Apple samples of gastric and intestinal phase digestive juices were obtained from an in vitro simulated digestion model. Our survey of in vitro digestion models found that the bioaccessibilities ranged from 4.42% to 31.22% and 10.58%-35.63% in the gastric and intestinal phases, respectively. A sharp trend similar to a normal distribution was observed between the bioaccessibilities and pH values. The bioaccessibility reached its highest value at a pH of 1.91 in the simulated gastric juice and did not significantly change with an increase of the digestive time. A significant negative correlation occurred between the bioaccessibility and S/L ratio, which followed a logarithmic equation. The correlation coefficients (R2) ranged from 0.9259 to 0.9831 and 0.9077 to 0.9960 in the simulated gastric and intestinal juice, respectively, suggested that both the pH value and S/L ratio were the main factors affecting the bioaccessibility. Furthermore, a combination of the acceptable daily intake (ADI) and bioaccessibility for human exposure assessments indicated the implication that traditional risk assessment using ADI may seriously overestimate the actual risk.


Assuntos
Trato Gastrointestinal/metabolismo , Modelos Biológicos , Praguicidas/farmacocinética , Piretrinas/farmacocinética , Disponibilidade Biológica , Exposição Ambiental , Humanos , Resíduos de Praguicidas , Praguicidas/metabolismo , Piretrinas/administração & dosagem , Piretrinas/metabolismo , Medição de Risco
14.
PLoS One ; 11(12): e0167748, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27936192

RESUMO

BACKGROUND: The cereal weevil, Sitophilus zeamais is one of the most destructive pests of stored cereals worldwide. Frequent use of fumigants for managing stored-product insects has led to the development of resistance in insects. Essential oils from aromatic plants including the tea oil plant, Melaleuca alternifolia may provide environmentally friendly alternatives to currently used pest control agents. However, little is known about molecular events involved in stored-product insects in response to plant essential oil fumigation. RESULTS: M. alternifolia essential oil was shown to possess the fumigant toxicity against S. zeamais. The constituent, terpinen-4-ol was the most effective compound for fumigant toxicity. M. alternifolia essential oil significantly inhibited the activity of three enzymes in S. zeamais, including two detoxifying enzymes, glutathione S-transferase (GST), and carboxylesterase (CarE), as well as a nerve conduction enzyme, acetylcholinesterase (AChE). Comparative transcriptome analysis of S. zeamais through RNA-Seq identified a total of 3,562 differentially expressed genes (DEGs), of which 2,836 and 726 were up-regulated and down-regulated in response to M. alternifolia essential oil fumigation, respectively. Based on gene ontology (GO) analysis, the majority of DEGs were involved in insecticide detoxification and mitochondrial function. Furthermore, an abundance of DEGs mapped into the metabolism pathway in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database were associated with respiration and metabolism of xenobiotics, including cytochrome P450s, CarEs, GSTs, and ATP-binding cassette transporters (ABC transporters). Some DEGs mapped into the proteasome and phagosome pathway were found to be significantly enriched. These results led us to propose a model of insecticide action that M. alternifolia essential oil likely directly affects the hydrogen carrier to block the electron flow and interfere energy synthesis in mitochondrial respiratory chain. CONCLUSION: This is the first study to perform a comparative transcriptome analysis of S. zeamais in response to M. alternifolia essential oil fumigation. Our results provide new insights into the insecticidal mechanism of M. alternifolia essential oil fumigation against S. zeamais and eventually contribute to the management of this important agricultural pest.


Assuntos
Fumigação/métodos , Melaleuca/química , Óleos Voláteis/toxicidade , Óleos Vegetais/toxicidade , Transcriptoma/efeitos dos fármacos , Gorgulhos/efeitos dos fármacos , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Óleos Voláteis/química , Óleos Vegetais/química , Gorgulhos/enzimologia , Gorgulhos/genética
15.
Molecules ; 20(1): 807-21, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25574822

RESUMO

A series of novel pyrazole amide derivatives 3a-3p which take TMV PC protein as the target has been designed and synthesized by the reactions of 5-chloro-1-aryl-3-methyl-1H-pyrazole-4-carboxylic acids with 5-amino-1-aryl-1H-pyrazole-4-carbonitriles. All the compounds were characterized by 1H-NMR, mass spectroscopy and elemental analysis. Preliminary bioassays indicated that all the compounds acted against the tobacco mosaic virus (TMV) with different in vivo and in vitro modes at 500 µg/mL and were found to possess promising activity. Especially, compound 3p showed the most potent biological activity against tobacco mosaic virus (TMV) compared to ningnanmycin, and a molecular docking study was performed and the binding model revealed that the pyrazole amide moiety was tightly embedded in the binding sites of TMV PC (PDB code: 2OM3).


Assuntos
Antivirais/química , Antivirais/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Antivirais/síntese química , Desenho de Fármacos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Pirazóis/síntese química , Relação Quantitativa Estrutura-Atividade , Espectrometria de Massas por Ionização por Electrospray
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