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Journal of Separation Science Mar 2024Herein, a deep eutectic solvent (DES)-based miniaturized pressurized liquid extraction in combination with DES-based dispersive liquid-liquid microextraction (DLLME) was...
Deep eutectic solvent-based pressurized liquid extraction combined with dispersive liquid-liquid microextraction of organophosphorus pesticide residues in egg powder prior to high-performance liquid chromatography analysis.
Herein, a deep eutectic solvent (DES)-based miniaturized pressurized liquid extraction in combination with DES-based dispersive liquid-liquid microextraction (DLLME) was developed for the extraction of organophosphorus pesticides (parathion-methyl, triazophos, parathion, diazinon, and phoxim) from egg powder samples prior to their analysis by a high-performance liquid chromatography-diode array detector. In this work, first, the analytes' extraction was done by a pressurized liquid phase extraction for effective extraction of the analytes from the solid matrix, and then they were concentrated on a DLLME for more concentration of the analytes to reach low limits of detections. The use of DESs was done in both steps to omit the use of toxic organic solvents. Satisfactory results including high extraction recoveries (74-90%), great repeatability (relative standard deviations equal or less than 4.3% and 5.3% for intra- and inter-day precisions), and low limits of detection (0.11-0.29 ng/g) and quantification (0.38-0.98 ng/g) were attained under the optimum conditions. Lastly, the suggested approach was utilized for the determination of the studied pesticides in various egg powder samples marketed in Tabriz, Iran.
Topics: Pesticide Residues; Liquid Phase Microextraction; Pesticides; Organophosphorus Compounds; Chromatography, High Pressure Liquid; Deep Eutectic Solvents; Powders; Parathion
PubMed: 38466171
DOI: 10.1002/jssc.202300070 -
Pesticide Biochemistry and Physiology Mar 2024Chemical sensing systems are vital in the growth and development of insects. Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important natural enemy of many...
Chemical sensing systems are vital in the growth and development of insects. Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important natural enemy of many pests. The molecular mechanism of odorant binding proteins (OBPs) binding with common insecticides is still unknow in O. sauteri. In this study, we expressed in vitro OsauOBP8 and conducted fluorescence competition binding assay to investigate the function of OsauOBP8 to insecticides. The results showed that OsauOBP8 could bind with four common insecticides (phoxim, fenitrothion, chlorpyrifos, deltamethrin). Subsequently, we used molecular docking to predict and obtained candidate six amino acid residues (K4, K6, K13, R31, K49, K55) and then mutated. The result showed that three key residues (K4, K6, R31) play important role in OsauOBP8 bound to insecticides. Our study identified the key binding sites of OsauOBP8 to insecticides and help to better understand the molecular mechanism of OBPs to insecticides in O. sauteri.
Topics: Animals; Insecticides; Molecular Docking Simulation; Heteroptera; Receptors, Odorant
PubMed: 38582604
DOI: 10.1016/j.pestbp.2024.105842 -
Bulletin of Entomological Research May 2024Carboxylesterases (CarEs) is an important detoxification enzyme system in phase Ⅰ participating in insecticides resistance. In our previous study, a CarEs gene from...
Carboxylesterases (CarEs) is an important detoxification enzyme system in phase Ⅰ participating in insecticides resistance. In our previous study, a CarEs gene from lepidoptera class, was screened out to be upregulated in a pyrethroids and organophosphates resistant population. Its overexpression was verified in two field-collected populations of (Lepidoptera: Noctuidae) resistant to pyrethroids and organophosphates by qRT-PCR. Spatiotemporal expression results showed that was highly expressed in the pupae stage and the digestive tissue midgut. To further explore its role in pyrethroids and organophosphates resistance, its metabolism activity to insecticides was determined by UPLC. Its recombinant protein showed significant metabolism activity to cyhalothrin and fenvalerate, but not to phoxim or chlorpyrifos. The metabolic activity of SlCarE054 to -cypermethrin showed stereoselectivity, with higher metabolic activity to -cypermethrin than the enantiomer -cypermethrin. The metabolite of -cypermethrin was identified as 3-phenoxybenzaldehyde. Further modelling and docking analysis indicated that -cypermethrin, cyhalothrin and fenvalerate could bind with the catalytic triad of the 3D structure of SlCarE054. The interaction of -cypermethrin with SlCarE054 also showed the lowest binding energy. Our work provides evidence that play roles in -cypermethrin resistance in .
PubMed: 38708572
DOI: 10.1017/S0007485324000282 -
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi =... May 2024Objective To establish a colloidal gold immunochromatography and develop the corresponding test strip for detecting organophosphorus compounds including omethoate,...
Objective To establish a colloidal gold immunochromatography and develop the corresponding test strip for detecting organophosphorus compounds including omethoate, phoxim, dipterex, and parathion in fruits, vegetables and drinking water. Methods Artificial antigen molecules of organophosphorus compounds were synthesized using N-hydroxysuccinimide esters. Acetylcholinesterase antigen was prepared and purified, and the serum containing the corresponding antibody was prepared, purified, and labeled. The working parameters of the test strip were optimized, and the performance evaluation of it was conducted. Results The titer of the antisera ranged from 1:32 to 1:64, with a protein content of approximately 2 mg/mL. The purified polyclonal antibodies displayed target bands at relative molecular masses (M) of 25 000 and 55 000, indicating satisfactory purity. The reaction time of the test strips was between 5 to 10 minutes, with a detection limit for samples at 200 ng/mL. Both specificity and accuracy were satisfactory, and the test strip remained valid for 6 months. Conclusion A simple and rapid colloidal gold immunochromatography is established successfully for detecting several organophosphorus compounds and may be useful for on-site preliminary screening of samples in large quantities.
Topics: Gold Colloid; Organophosphorus Compounds; Chromatography, Affinity; Pesticides; Animals; Vegetables; Fruit; Acetylcholinesterase
PubMed: 38790099
DOI: No ID Found -
International Journal of Biological... Mar 2024Glyphodes pyloalis (Lepidoptera: Pyralidae) is one of the major pests in mulberry production in China, which has developed resistance to various insecticides....
Glyphodes pyloalis (Lepidoptera: Pyralidae) is one of the major pests in mulberry production in China, which has developed resistance to various insecticides. Chemoreception is one of the most crucial physiological tactics in insects, playing a pivotal role in recognizing chemical stimuli in the environment, including noxious stimuli such as insecticides. Herein, we obtained recombinant pheromone-binding protein 1 (GpylPBP1) that exhibited antennae-biased expression in G. pyloalis. Ligand-binding assays indicated that GpylPBP1 had the binding affinities to two organophosphorus insecticides, with a higher binding affinity to chlorpyrifos than to phoxim. Computational simulations showed that a mass of nonpolar amino acid residues formed the binding pocket of GpylPBP1 and contributed to the hydrophobic interactions in the bindings of GpylPBP1 to both insecticides. Furthermore, the binding affinities of three GpylPBP1 mutants (F12A, I52A, and F118A) to both insecticides were all significantly reduced compared to those of the GpylPBP1-wild type, suggesting that Phe12, Ile52, and Phe118 residues were crucial binding sites and played crucial roles in the bindings of GpylPBP1 to both insecticides. Our findings can be instrumental in elucidating the effects of insecticides on olfactory recognition in moths and facilitating the development of novel pest management strategies using PBPs as targets based on insect olfaction.
Topics: Animals; Insecticides; Carrier Proteins; Pheromones; Organophosphorus Compounds; Moths; Recombinant Proteins; Insect Proteins
PubMed: 38218287
DOI: 10.1016/j.ijbiomac.2024.129339