Search Results (24)

After eight generations of laboratory selection with β-cypermethrin, a P. okadai strain was cultivated that displayed a 10.04-fold increase in resistance (RS) relative to the susceptible strain (SS), with an estimation of heritability (h²) of 0.34. Compared with the SS, the developmental duration of the eggs was significantly prolonged (p < 0.05); however, the pupal stage duration was shorter, with no statistically significant difference. Moreover, the levels of GSTs, CarEs, and CYP450 activity were notably higher in the RS than in the SS. In addition, the level of CarE and CYP450 activity in the RS was significantly higher in the midgut (MG), fat body (FB), and Malpighian tubules (MTs) compared to the SS; however, the GSTs showed no statistically significant difference in the MTs. These results suggest that P. okadai‘s resistance to β-cypermethrin could be selected rapidly and the decreases in the intrinsic rate of increase (r) observed in the RS are likely due to mutations in the detoxification enzyme genes under the strong selection pressure exerted by β-cypermethrin. The increased activity of GSTs, CarEs, and CYP450 was associated with β-cypermethrin resistance in the RS of P. okadai. The data reported herein provide a foundation for future studies on the mechanisms responsible for β-cypermethrin resistance in P. okadai. Full article

β-cypermethrin (BCP) is a broad-spectrum insecticide known for its rapid efficacy. However, it is highly toxic to non-target organisms such as bees and fish, and its effectiveness is limited by a short duration of action. Improving the release profile of BCP is essential for reducing its environmental toxicity while preserving its effectiveness. In this study, hollow mesoporous silica nanoparticles (HMSNs) were synthesized using a self-templating method, and BCP-loaded HMSNs were prepared through physical adsorption. The structural and physicochemical properties of the nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption analysis, Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), and thermogravimetric analysis (TGA). The BCP release profile was assessed using the dialysis bag method. The results showed that the synthesized nanoparticles exhibited uniform morphology, thin shells, and large internal cavities. The HMSNs had a pore size of 3.09 nm, a specific surface area of 1318 m²·g⁻¹, a pore volume of 1.52 cm³·g⁻¹, and an average particle size of 183 nm. TEM, FT-IR, and TGA analyses confirmed the successful incorporation of BCP into the HMSNs, achieving a drug loading efficiency of 32.53%. The BCP-loaded nanoparticles exhibited sustained-release properties, with an initial burst followed by gradual release, extending efficacy for 30 days. Safety evaluations revealed minimal toxicity to maize seedlings, confirming the biocompatibility of the nanoparticles. These findings indicate that BCP-loaded HMSNs can enhance the efficacy of BCP while reducing its environmental toxicity, providing a biocompatible and environmentally friendly solution for pest control. Full article

Aedes aegypti and Anopheles darlingi are the primary vectors of dengue and malaria in Brazil. Natural products are currently regarded as promising alternatives for their control, offering environmentally friendly solutions for larval management due to their low toxicity to non-target organisms. Thus, Piplartine, isolated for the first time from Piper purusanum, exhibited larvicidal activity against Ae. aegypti and An. darlingi (LC₅₀ of 14.56 and 26.44 μg/mL), occasioned by the overproduction of reactive oxygen and nitrogen species (66.67 ± 7% and 86.33 ± 6%). Furthermore, piplartine enhanced the activity of key detoxifying enzymes, including catalase (87.00 ± 9 and 94.67 ± 9 μmol of H₂O₂ consumed per minute per mg of protein), glutathione S-transferase (76.00 ± 1 and 134.00 ± 1 μmol/min/mg), mixed-function oxidase (26.67 ± 5 and 55.00 ± 1 nmol cti mg⁻¹ protein), α-esterase, and β-esterase (27.67 ± 7 to 46.33 ± 1 nmol cti mg⁻¹ protein). In contrast, piplartine inhibited acetylcholinesterase activity (43.33 ± 7 and 48.00 ± 2 μmol/min/mg) compared to the negative control DMSO (87.33 ± 1 and 146.30 ± 3 μmol/min/mg). It is important to highlight that piplartine showed no lethal effects on non-target aquatic insects, with 100% survival observed at a concentration of 264.4 μg/mL. In contrast, α-cypermethrin demonstrated acute and rapid toxicity to non-target organisms, with only 9.1% survival. These findings highlight piplartine as a promising larvicide with selective toxicity and low environmental impact, suitable for integrated larval management strategies. Full article

Pyrethroids are one of the most commonly used insecticides worldwide in agriculture, public health, and household products. To monitor the presence of pyrethroids in the environment and in food, a broad-spectrum monoclonal antibody (mAb), CL/CN-1D2, was prepared. This mAb demonstrates a 50% inhibitory concentration (IC50) for different pyrethroids: cypermethrin (129.1 µg/L), β-cypermethrin (199.6 µg/L), cyfluthrin (215.5 µg/L), fenpropathrin (220.3 µg/L), λ-cyhalothrin (226.9 µg/L), β-cyfluthrin (241.7 µg/L), deltamethrin (591.2 µg/L), and fenvalerate (763.1 µg/L). Using the mAb CL/CN-1D2, a highly sensitive heterologous indirect competitive ELISA (ic-ELISA) was developed for the rapid detection of these pyrethroids. The limit of detection (LOD) for the eight pyrethroids in water, milk, celery, and leek matrices ranged from 24.4 to 152.2 μg/kg. The recoveries ranged from 65.1% to 112.4%, with a coefficient of variation (CV) below 15%. A robust correlation (R² = 0.9945) between the ic-ELISA and GC indicated that the ic-ELISA is a reliable tool for the rapid and cost-effective screening of pyrethroids residues. Full article

Background: β-cypermethrin (β-CYP) exhibits high toxicity to aquatic organisms and poses significant risks to aquatic ecosystems. Tetrahymena thermophila, a protozoa widely distributed in aquatic environments, can tolerate high concentrations of β-cypermethrin. However, the comprehensive detoxification mechanisms remain poorly understood in Tetrahymena. Methods: Untargeted metabolomics was used to explore the detoxification mechanisms of T. thermophila under β-CYP stress. Results: Trehalose, maltose, glycerol, and D-myo-inositol were upregulated under β-CYP exposure in Tetrahymena. Furthermore, the expression level of CYP5011A1 was upregulated under β-CYP treatment. CYP5011A1 knockout mutants resulted in a decreasing proliferation rate of T. thermophila under β-CYP stress. The valine–leucine and isoleucine biosynthesis and glycine–serine and threonine metabolism were significantly affected, with significantly changed amino acids including serine, isoleucine, and valine. Conclusions: These findings confirmed that T. thermophila develops β-CYP tolerance by carbohydrate metabolism reprogramming and Cyp5011A1 improves cellular adaptations by influencing amino acid metabolisms. Understanding these mechanisms can inform practices aimed at reducing the adverse effects of agricultural chemicals on microbial and environmental health. Full article

Insecticides are used commonly in agricultural production to defend plants, including legumes, from insect pests. It is a known fact that insecticides can have a harmful effect on the legume–rhizobial symbiosis. In this study, the effects of systemic seed treatment insecticide Imidor Pro (imidacloprid) and foliar insecticide Faskord (alpha-cypermethrin) on the structural organization of pea (Pisum sativum L.) nodules and their transcriptomic activity were investigated. The plants were treated as recommended by the manufacturer (10 mg/mL for Imidor Pro and 50 µg/mL for Faskord) and twofold concentrations were used for both insecticides. Insecticides had no visible effect on the growth of pea plants. The nodules also showed no visible changes, except for the variant treated with twofold concentration of Imidor Pro. However, the dry weight of shoots and roots differed significantly in insecticide-treated plants compared to untreated plants in almost all treatments. The number of nodules decreased in variants with Imidor Pro treatment. At the ultrastructural level, both insecticides caused cell wall deformation, poly-β-hydroxybutyrate accumulation in bacteroids, expansion of the peribacteroid space in symbiosomes, and inclusions in vacuoles. Treatment with Faskord caused chromatin condensation in nucleus. Imidor Pro treatment caused hypertrophy of infection droplets by increasing the amount of matrix, as confirmed by immunofluorescence analysis of extensins. Transcriptome analysis revealed upregulation of expression of a number of extensin-like protein-coding genes in nodules after the Imidor Pro treatment. Overall, both insecticides caused some minor changes in the legume–rhizobial system when used at recommended doses, but Faskord, an enteric contact insecticide, has fewer negative effects on symbiotic nodules and legume plants; of these two insecticides, it is preferred in pea agricultural production. Full article

Insecticides are widely used to boost crop yields, but their effects on non-target insects like Vespa magnifica are still poorly understood. Despite its ecological and economic significance, Vespa magnifica has been largely neglected in risk assessments. This study employed physiological, biochemical, and transcriptomic analyses to investigate the impact of sublethal concentrations of thiamethoxam, avermectin, chlorfenapyr, and β-cypermethrin on Vespa magnifica. Although larval survival rates remained unchanged, both pupation and fledge rates were significantly reduced. Enzymatic assays indicated an upregulation of superoxide dismutase and catalase activity alongside a suppression of peroxidase under insecticide stress. Transcriptomic analysis revealed increased adenosine triphosphate-related processes and mitochondrial electron transport activity, suggesting elevated energy expenditure to counter insecticide exposure, potentially impairing essential functions like flight, hunting, and immune response. The enrichment of pathways such as glycolysis, hypoxia-inducible factor signaling, and cholinergic synaptic metabolism under insecticide stress highlights the complexity of the molecular response with notable effects on learning, memory, and detoxification processes. These findings underscore the broader ecological risks of insecticide exposure to non-target insects and highlight the need for further research into the long-term effects of newer insecticides along with the development of strategies to safeguard beneficial insect populations. Full article

In defining the research objective, consideration was given to the expanding range of applications of third-generation pyrethroids, including cypermethrin—the active substance in Arpon G preparation. The interest in cypermethrin is due to its high thermostability and photostability. This study verified the effect of Arpon G on both the soil condition and the growth and development of Zea mays. To this end, the alpha and beta diversity of bacterial and fungal communities were characterized using the NGS (Next Generation Sequencing) method, as was the response of soil enzymes. The positive response of Z. mays to the soil application of cypermethrin corresponded to higher soil microbial and biochemical activity. Sowing the soil with Z. mays moderated changes in the biodiversity of alpha- and beta-bacterial communities to a greater extent than cypermethrin. The influence of both parameters was less significant for fungi. Although bacteria belonging to the Actinobacteria phylum and fungi from the Ascomycota phylum dominated in the soil, the use of Arpon G reduced the abundance of unique nucleotide sequences in the mycobiome to a greater extent than in the bacteriobiome. The inhibitory potential of Arpon G was only evident for acid phosphatase (by 81.49%) and arylsulfatase (by 16.66%) in the soil sown with Z. mays. The activity of catalase, dehydrogenases, β-glucosidase, arylsulfatase, and alkaline phosphatase was most strongly associated with the abundance of bacteria, while dehydrogenases were correlated with the abundance of fungi at the genus level. Arpon G can, thus, be considered a safe insecticide for soil conditions and, consequently, for its productive function. Full article

Cypermethrin (CPM) is the most toxic synthetic pyrethroid that has established neurotoxicity through oxidative stress and neurochemical agitation in experimental rats. The toxic effects are supposed to be mediated by modifying the sodium channels, reducing Na-K ATPase, acetylcholine esterase (AchE), and monoamine oxidase (MAO). The use of curcumin nanoparticles (NC) that have potent antioxidant, anti-inflammatory and antiapoptotic properties with improved bioavailability attenuates neurotoxicity in rat brains. To test this hypothesis, animals were divided into five groups, each having six animals. Group-I control received vehicle only, while Group-II was treated with 50 mg/kg CPM. Group-III and Group-IV received both CPM and NC 2.5 mg/kg and 5 mg/kg, respectively. Group-V received 5 mg of NC alone. The CPM and NC were given by oral route. Afterwards, brain antioxidant status was measured by assessing lipid peroxidation (LPO), 4-HNE, glutathione reduced (GSH), antioxidant enzyme catalase, and superoxide dismutase (SOD) along with neurotoxicity markers Na-K ATPase, AchE, and MAO. Inflammation and apoptosis indices were estimated by ELISA, qRT-PCR, and immunohistochemistry, while morphologic changes were examined by histopathology. Observations from the study confirmed CPM-induced neurotoxicity by altering Na-K ATPase, AchE, and MAO, and by decreasing the activity of antioxidant enzymes and GSH. Oxidative stress marker LPO and the level of inflammatory interleukins IL-6, IL-1β, and TNF-α were notably high, and elevated expressions of Bax, NF-kB, and caspase-3 and -9 were reported in CPM group. However, NC treatment against CPM offers protection by improving antioxidant status and lowering LPO, inflammation, and apoptosis. The neurotoxicity marker’s enzyme successfully attenuated after NC treatment. Therefore, this study supports the administration of NC effectively ameliorated CPM-induced neurotoxicity in experimental rats. Full article

Background: Spodoptera littoralis (Boisd.) is a prominent agricultural insect pest that has developed resistance to a variety of insecticide classes. In this study, the resistance of three field strains of S. littoralis, collected over three consecutive seasons (2018 to 2020) from three Egyptian Governorates (El-Fayoum, Behera and Kafr El-Shiekh), to six insecticides was monitored. Methods: Laboratory bioassays were carried out using the leaf-dipping method to examine the susceptibility of the laboratory and field strains to the tested insecticides. Activities of detoxification enzymes were determined in an attempt to identify resistance mechanisms. Results: The results showed that LC₅₀ values of the field strains ranged from 0.0089 to 132.24 mg/L, and the corresponding resistance ratio (RR) ranged from 0.17 to 4.13-fold compared with the susceptible strain. Notably, low resistance developed to spinosad in all field strains, and very low resistance developed to alpha-cypermethrin and chlorpyrifos. On the other hand, no resistance developed to methomyl, hexaflumeron or Bacillus thuringiensis. The determination of detoxification enzymes, including carboxylesterases (α- and β-esterase), mixed function oxidase (MFO) and glutathione-S-transferase (GST), or the target site of acetylcholinesterase (AChE), revealed that the three field strains had significantly different activity levels compared with the susceptible strain. Conclusion: Our findings, along with other tactics, are expected to help with the resistance management of S. littoralis in Egypt. Full article

This study investigated the potential hepatoprotective activity of curcumin-incorporated nano-lipid carrier (Cur-NLC) against cypermethrin (Cyp) toxicity in adult Wistar male rats. All animals in groups III, IV, V, and VI were subjected to Cyp (50 mg/kg) toxicity for 15 days. Three different doses of Cur-NLC (1, 2.5, and 5 mg/kg/day) were administered orally for 10 days. The toxic effects were evaluated considering the increases in serum hepatic biomarkers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total protein and albumin, and lipid peroxidation (LPO), as well as a decrease in antioxidative activity (reduced glutathione (GSH), superoxide dismutase (SOD), and catalase) and the upregulation of inflammatory cytokines (IL-1β, IL-6, and TNF-α). Immunohistochemistry studies of proteins (NF-κB, Apaf-1, 4-HNE, and Bax) showed enhanced expression, and histopathological examination revealed architectural changes in liver cells, indicating liver toxicity in animals. Toxicity was determined by quantitative and qualitative determinations of DNA fragmentation, which show massive apoptosis with Cyp treatment. The administration of Cur-NLC significantly ameliorates all changes caused by Cyp, such as a decrease in the levels of serum liver markers, an increase in antioxidative parameters, a decrease in expression of inflammatory cytokines (IL-1β, IL-6, TNF-α, and NF-κB), and apoptosis (caspases-3, 9, Apaf-1, 4-HNE, and Bax), according to calorimetric and immunohistochemistry studies. The smear-like pattern of DNA is ameliorated similarly to the control at a high dose of Cur-NLC. Furthermore, all histopathological changes were reduced to a level close to the control. In conclusion, Cur-NLC could be a potent nutraceutical that exhibits a hepatoprotective effect against Cyp-induced hepatotoxicity in rats. Full article

Phortica okadai, a polyphagous pest, serves as a vector for Thelazia callipaeda in China. Currently, there are no effective control strategies for this vector. Agricultural pest control may cause P. okadai to become a threat due to the development of pesticide resistance. Cytochrome P450s (CYP450) plays a significant role in detoxifying xenobiotics in insects. In this study, we performed RNA sequencing of P. okadai exposed to β-cypermethrin for 0 and 1 h and then gene cloning of the five up-regulated CYP450 genes. Three CYP450 genes were successfully cloned, and their expression patterns in different developmental stages and in different tissues were analyzed by RT-qPCR. Pocyp4d2 was observed to have the highest expression in the midgut (fold change 2.82 for Pocyp4d2, 2.62 for Pocyp49a1, and 1.77 for Pocyp28d2). Functional analysis was carried out according to overexpression in S2 cells from the pfastbac1 vector and RNAi with siRNA. The results of the CCK8 assay indicated that the overexpression of the recombinant protein PoCYP4D2 suppressed the decrease in S2 cell viability due to β-cypermethrin. The expression levels of PoCYP4D2 decreased significantly, and the mortality rates increased from 6.25% to 15.0% at 3 h and from 15.0% to 27.5% at 6 h after Pocyp4d2-siRNA injection. These results suggest that Pocyp4d2 may be an essential key gene in the metabolism of β-cypermethrin in P. okadai. This study constitutes a foundation to explore further the functions of P. okadai CYP450 genes in insecticide metabolism. Full article

The long-term use of chemical insecticides has caused serious problems of insect resistance and environmental pollution; new insecticides are needed to solve this problem. Cyclosporin A (CsA) is a polypeptide produced by many fungi, which is used to prevent or treat immune rejection during organ transplantation. However, little is known about the utility of CsA as an insecticide. Therefore, this study evaluated the insecticidal activity of CsA using Ostrinia furnacalis as a model. The results demonstrated that CsA was toxic to O. furnacalis with LC₅₀ values of 113.02 μg/g and 198.70 μg/g for newly hatched neonates and newly molted third-instar larvae, respectively. Furthermore, CsA treatment had sublethal effects on the development of O. furnacalis, and significantly reduced the fecundity of adults; this suggests that CsA has great potential to suppress O. furnacalis populations. Further analysis revealed that CsA suppressed calcineurin activity in larvae. CsA had independent or synergistic toxic effects on O. furnacalis when combined with β-cypermethrin, indoxacarb, emamectin benzoate, azadirachtin, and the Bacillus thuringiensis toxin Cry1Ac, which suggests that CsA can help prevent or manage resistance. Our study provides detailed information on the potential of CsA as an insecticide for controlling lepidopterans. Full article

Globally, the quality of agricultural soils is in decline as a result of mismanagement and the overuse of agrichemicals, negatively impacting crop yields. Agaricus subrufescens Peck is widely cultivated as an edible and medicinal mushroom; however, its application in soil bioremediation and amendment remains insufficiently studied. In order to determine if A. subrufescens can positively impact agricultural soils, we designed two experiments: the first, a glasshouse experiment investigating the ways in which A. subrufescens production alters soil nutrients and soil health; the second, a laboratory experiment investigating if A. subrufescens can degrade beta-cypermethrin (β-CY) and glufosinate ammonium (Gla), two widely used agrichemicals. The glasshouse experiment results indicated that the use of compost and compost combined with A. subrufescens led to increases in soil organic matter, nitrogen, phosphorus, and potassium compared to the control treatments (sterilized soil). However, the incorporation of A. subrufescens with compost resulted in significantly greater levels of both available nitrogen and available phosphorus in the soils compared to all other treatments. Laboratory experiments determined that the mycelium of A. subrufescens were unable to grow at concentrations above 24.71 μg/mL and 63.15 μg/g for β-CY and Gla, respectively. Furthermore, results indicated that fungal mycelia were able to degrade 44.68% of β-CY within 15 days, whereas no significant changes were found in the concentration of Gla. This study highlights that cultivation of A. subrufescens may be a sustainable alternative for the rehabilitation of agricultural soils, whilst providing an additional source of income for farmers. Full article

The oriental fruit fly, Bactrocera dorsalis, is one of the most destructive fruit insect pests. β-cypermethrin has been widely used in the orchard to control this major insect. Based on the resistance monitoring in 2011, B. dorsalis developed significant resistance against β-cypermethrin in fields. This indicated that the B. dorsalis has been exposed to sublethal concentrations of β-cypermethrin in the field for a long time. Thus, it is urgent to understand the sublethal effects of β-cypermethrin on this fly to guide the rational use of an insecticide. According to the olfactory preference assays and electroantennogram (EAG) recording, the B. dorsalis after β-cypermethrin exposure (LD₃₀ = 10 ng/fly) severely decreased the ability to perceive the tested odorants. Moreover, we then performed quantitative real-time PCR and found the chemosensory genes including odorant receptor co-receptor (BdorORco) and ionotropic receptor co-receptors (BdorIRcos) were obviously suppressed. Our results demonstrated that the sublethal dose of β-cypermethrin impairs the olfaction of the pest insects by suppressing the expression of chemosensory genes (BdorORco and BdorIRcos), which expanded our knowledge of the sublethal effects of the pesticide on insects. Full article