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Objective: Standardize the use of phoxim to ensure the safety of aquatic products. Methods: Taking freshwater crucian carp as the research object, Selecting phoxim, an organic phosphorus pesticide often used in agriculture, as the representative of exogenous environmental pollutants. The changes in normal physiological metabolism of crucian carp exposed to phoxim were studied by using the 1H-NMR metabonomics method combined with PCA, PLS-DA, OPLS-DA and other multivariate statistical methods. Based on this, the toxic effects of phoxim on crucian carp and the toxicological mechanism of phoxim in the crucian carp were deduced. Results: Compared with the control group, the metabolites in the crucian carp serum sample of the phoxim group have a significant increase in concentration of 3-HB, glucose and phenylalanine, and a significant decrease of glutamic acid, alanine, asparagine, histidine, lactic acid, glycerol phosphate of choline, phosphoric acid, choline, choline and unsaturated fatty acids, lipids, guanine nucleoside, inosine(P＜0.05). Conclusion: The results showed that phoxim can change amino acid metabolism, energy metabolism, disturbance of neurotransmitter balance and oxidative stress in crucian carp.and the endogenous metabolites change may be related to Ⅱ metabolic reactions of phoxim in crucian carp.

Glutathione S‐transferases (GSTs) were reported to participate in insecticide resistance by metabolic and antioxidant activities. In our previous study, an ε class gene of GSTs, SlGSTe8 in Spodoptera litura, was screened out to be upregulated in a population resistant to pyrethroids and organophosphates. SlGSTe8 was highly expressed in the larvae stage, and the digestive tissue, foregut, midgut and hindgut, while the relative expression level was low in the pupae stage and other tissues. To further explore its role in the resistance to pyrethroids and organophosphates, the metabolic activity to insecticides by its recombinant protein was determined by Ultra Performance Liquid Chromatography, and its antioxidant enzyme activity was evaluated by disc diffusion assay. The recombinant protein showed significant metabolic activity to phoxim and chlorpyrifos, but not to fenvalerate, cyhalothrin or β‐cypermethrin. After incubation, the depletion rate of chlorpyrifos is 85.3%, higher than that of phoxim (17.5%). Also, the inhibition zone around filter discs decreased significantly after exposure to cumene hydroperoxide in recombinant plasmid than vector only, suggesting significant antioxidant activity of SlGSTE8. Further modelling and docking analysis indicated that the 3D structure of SlGSTE8 was well shaped for phoxim and chlorpyrifos, with the binding energy −5.58 and −5.15 kcal/mol, respectively. Our work provides evidence that SlGSTe8 in S. litura plays important roles in phoxim and chlorpyrifos resistance. [ABSTRACT FROM AUTHOR]

Exposure to phoxim at low levels caused bioaccumulation with neurotoxicity but also induced oxidative stress, tissue damage, and abnormal nutrient metabolism. This study described that vitamin E ameliorates phoxim-induced nephrotoxicity via inhibiting mitochondrial apoptosis. In vivo, 24 healthy piglets were treated with phoxim (0 mg/kg and 500 mg/kg) and vitamin E + phoxim (vitamin E + phoxim: 200 mg/kg + 500 mg/kg). In vitro, PK15 cells were treated with phoxim (0 mg/L and 1 mg/L) and vitamin E + phoxim (phoxim + vitamin E: 1 mg/L + 1 mg/L) for 12 h and 24 h. Our results indicated that accumulation of ROS, oxidative stress, and renal cell injury through stimulation of mitochondrial apoptosis resulted in phoxim-induced nephrotoxicity. Phoxim resulted in swollen mitochondria, blurred internal cristae, renal glomerular atrophy, and renal interstitial fibrosis. Vitamin E alleviated the adverse effects of phoxim by reducing ROS and improving antioxidant capacity in vivo and in vitro. Vitamin E significantly increased SDH in vitro (p < 0.01), while it decreased ROS, Bad, and cyto-c in vitro and SOD and CAT in vivo (p < 0.05). Vitamin E ameliorated phoxim-induced renal histopathologic changes, and mitochondria swelled. In addition, vitamin E regulates phoxim-induced apoptosis by alleviating oxidative damage to the mitochondria. [ABSTRACT FROM AUTHOR]

Infestations of brown dog ticks (Rhipicephalus sanguineus) are difficult to control. This study aimed to evaluate the efficacy of phoxim and deltamethrin against R. sanguineus In vitro and in vivo. In vitro studies, the evaluation involved the exposure of R. sanguineus adults, nymphs, and larvae to phoxim (1 ml/1000 ml) and deltamethrin (1 ml/1000 ml) observations were recorded for 24 hours, and the eggs were assessed and compared with a negative control tick group that had been exposed to water for 14 days, In vivo studies, twenty local dogs have been divided into four groups of five each: The 1st group was non-infested dogs; the 2nd group is infested untreated dogs; the 3rd group was infested dogs and treated with a therapeutic dose of phoxim; and 4th group was infested dogs and treated with a therapeutic dose of deltamethrin. Results revealed that phoxim was more effective than deltamethrin on adult of R. sanguineus, while deltamethrin appeared to be more effective than phoxim on nymphs and larvae of R. sanguineus. Both acaricides significantly inhibited egg hatchability of R. sanguineus with the same potency. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contamination with pesticides has inflicted substantial harm on human health; therefore, developing rapid, ultra-sensitive, and non-labelling simultaneous detection methods for multiple pesticides is necessary. In this study, we demonstrated that α-hemolysin (α-HL) nanopore sensor can detect and discriminate organophosphorus pesticides of phoxim and omethoate in a single nanopore without requiring labels of the probes or purification of the pesticides in real samples. Aptamers specifically recognise and bind pesticides to obtain pesticide-aptamer complexes that produce characteristic current signals while passing through the nanopore. Phoxim and omethoate were accurately distinguished by a portable instrument within minutes, and their detection sensitivity was up to the femtomole level, whether detected alone or simultaneously. The detection limits of phoxim and omethoate were 8.13 × 10−16 M and 4.16 × 10−15 M. The recoveries of phoxim and omethoate from pear, tomato, and cucumber samples were 82.0–107.0 % and 81.9–118.3 % respectively, with coefficient of variable below 8.0 %. • The α-hemolysin nanopore sensor can detect and discriminate phoxim and omethoate in real samples. • The sensor enables simultaneously detection of phoxim and omethoate within minutes. • The detection limit of the sensor is up to the femtomole level. • The sensor is as reliable and accurate as UHPLC-MS/MS. [ABSTRACT FROM AUTHOR]

Phoxim, extensively utilized in agriculture as an organothiophosphate insecticide, has the potential to cause neurotoxicity and pose human health hazards. In this study, an electrochemical enzyme biosensor based on Ti 3 C 2 MXene/MoS 2 @AuNPs/AChE was constructed for the sensitive detection of phoxim. The two-dimensional multilayer structure of Ti 3 C 2 MXene provides a robust framework for MoS 2 , leading to an expansion of the specific surface area and effectively preventing re-stacking of Ti 3 C 2 MXene. Additionally, the synergistic effect of self-reduced grown AuNPs with MoS 2 further improves the electrical conductivity of the composites, while the robust framework provides a favorable microenvironment for immobilization of enzyme molecules. Ti 3 C 2 MXene/MoS 2 @AuNPs electrochemical enzyme sensor showed a significant response to phoxim in the range of 1 × 10−13 M to 1 × 10−7 M with a detection limit of 5.29 × 10−15 M. Moreover, the sensor demonstrated excellent repeatability, reproducibility, and stability, thereby showing its promising potential for real sample detection. • AuNPs was assembled onto Ti 3 C 2 MXene/MoS 2 substrates by self-reduction for sensitive detection of phoxim in fruit. • The electrochemical biosensor had a wide linear range of phoxim detection with a LOD of 5.29 × 10−15 M. • The electrochemical biosensor has good stability, selectivity and reproducibility. [ABSTRACT FROM AUTHOR]

Carboxylesterase (CarE) was considered as important phase-I detoxifying enzymes which participated in detoxification of different types of insecticides. Up-regulation of CarE genes has been proved playing a major role in insecticide resistance in many pest insects, but its involvement in resistance to insecticides in Plutella xylostella has been rarely reported. In this study, a CarE cDNA named PxαE8 was identified in P. xylostella, which has an open reading frame of 1 599 nucleotides and putatively encodes 532 amino acids. The investigation of spatial expression profiles of PxαE8 revealed that it was expressed in all developmental stages, especially in larvae and adults. The body part/tissue-specific expression profiles showed that the PxαE8 mainly expressed in fat body, malpighian tubule and hemolymph of larvae. Further, the relative expression of PxαE8 in two multi-resistant field populations, Hainan (HN) and Guangdong (GD) populations, was found 24.4- and 15.5-fold higher than that in susceptible population, respectively. Knockdown of PxαE8 by RNA interference dramatically increased the mortalities of larvae of HN population treated with LC50 of beta-cypermethrin and phoxim by 25.3 and 18.3%, respectively. These results suggested that up-regulation of PxαE8 was involved in resistance to both beta-cypermethrin and phoxim in P. xylostella, which shed light on further understanding of molecular mechanisms of multi-insecticide-resistance in P. xylostella and other pest insects.

In order to develop a fluorometric aptamer-based biosensor for ultrasensitive and selective detection of phoxim, a modified magnetic beads-systematic evolution of ligands by exponential enrichment (MB-SELEX) method was used in this study to select phoxim aptamer. An aptamer (APT3) that bonded to phoxim with high affinity was obtained after 15 rounds of selection, which had dissociation constant (Kd) of 0.93 ​± ​0.25 ​μM. A fluorometric aptasensor was then developed and enhanced the sensitivity and selectivity of phoxim detection based on APT3, multi-complementary strands (CS) and gold nanoparticles (AuNPs). This method had a good linear range of 0.05–5 ​μM, and detection limit was as low as 29.69 ​nM for phoxim. In addition, the aptasensing specifically captured phoxim in a variety of pesticides and real samples. The herein results proved that the method can be applied in practical detection.

Exposure to phoxim at low levels caused bioaccumulation with neurotoxicity but also induced oxidative stress, tissue damage, and abnormal nutrient metabolism. This study described that vitamin E ameliorates phoxim-induced nephrotoxicity via inhibiting mitochondrial apoptosis. In vivo, 24 healthy piglets were treated with phoxim (0 mg/kg and 500 mg/kg) and vitamin E + phoxim (vitamin E + phoxim: 200 mg/kg + 500 mg/kg). In vitro, PK15 cells were treated with phoxim (0 mg/L and 1 mg/L) and vitamin E + phoxim (phoxim + vitamin E: 1 mg/L + 1 mg/L) for 12 h and 24 h. Our results indicated that accumulation of ROS, oxidative stress, and renal cell injury through stimulation of mitochondrial apoptosis resulted in phoxim-induced nephrotoxicity. Phoxim resulted in swollen mitochondria, blurred internal cristae, renal glomerular atrophy, and renal interstitial fibrosis. Vitamin E alleviated the adverse effects of phoxim by reducing ROS and improving antioxidant capacity in vivo and in vitro. Vitamin E significantly increased SDH in vitro (p < 0.01), while it decreased ROS, Bad, and cyto-c in vitro and SOD and CAT in vivo (p < 0.05). Vitamin E ameliorated phoxim-induced renal histopathologic changes, and mitochondria swelled. In addition, vitamin E regulates phoxim-induced apoptosis by alleviating oxidative damage to the mitochondria.

Malathion, phoxim, and thiram are organophosphates and organosulfur pesticides widely used in agricultural products. The residues of these pesticides present a direct threat to human health. Rapid and on-site detection is critical for minimizing such risks. In this work, a simple approach was introduced using a flexible surface-enhanced Raman spectroscopy (SERS) substrate. The prepared Ag nanoparticles-polydimethylsiloxane (AgNPs-PDMS) substrate showed high SERS activity, good precision (relative standard deviation = 5.33%), and stability (30 days) after optimization. For target pesticides, the linear relationship between characteristic SERS bands and concentrations were achieved in the range of 10~1000, 100~5000, and 50~5000 μg L−1 with LODs down to 3.62, 41.46, and 15.69 μg L−1 for thiram, malathion, and phoxim, respectively. Moreover, SERS spectra of mixed samples indicated that three pesticides can be identified simultaneously, with recovery rates between 96.5 ± 3.3% and 118.9 ± 2.4%, thus providing an ideal platform for detecting more than one target. Pesticide residues on orange surfaces can be simply determined through swabbing with the flexible substrate before acquiring the SERS signal. This study demonstrated that the prepared substrate can be used for the rapid detection of pesticides on real samples. Overall, this method greatly simplified the pre-treatment procedure, thus serving as a promising analytical tool for rapid and nondestructive screening of malathion, phoxim, and thiram on various agricultural products. [ABSTRACT FROM AUTHOR]

Phoxim is one of the main organophosphorus pesticides used in agricultural production. However, little information is known about how it affects the aquatic microbial community and the intestinal microbiota of fish. Herein, we utilized shotgun metagenomics and 16S rRNA gene sequencing to reveal the aquatic eco-risk of phoxim. Seven days of phoxim exposure significantly changed the composition of aquatic microbial community, obliterated the interactions between microorganisms, and thus reduced the complexity and stability of the microbial community. During long-time exposure (i.e., 14 days), most of the ecological functions were restored due to the redundancy of the microbial community. However, phoxim exposure promoted the dissemination of elfamycin resistance gene. The zebrafish gut microbial community also recovered from a temporary ecological disorder of aquatic microbiota, but phoxim continually affected zebrafish growth and swimming behavior. Overall, our results demonstrated that phoxim exposure significantly changed the structure and function of the microbial community and displayed a negative impact on freshwater ecosystems in a short exposure time. [ABSTRACT FROM AUTHOR]

Simple Summary: The poultry red mite Dermanyssus gallinae is a blood-sucking ectoparasite responsible for serious animal health and welfare concerns in egg-laying hen facilities, with impacts on productivity and public health. Traditionally, its control is based on the use of synthetic acaricides. Their extensive use has resulted in the development of acaricide resistance. While industrial farms are under strict legislative control, amateur breeders tend to use cheaper pesticides such as phoxim (licensed in poultry) but potentially also unauthorized pesticides, such as fipronil. The aim of this study was to evaluate the in vitro acaricidal activity of different concentration of these two molecules on field populations of D. gallinae, collected from ornamental chicken farms in Italy. Their effectiveness was significantly associated with the dose used, but a great variability of lethality rate was observed for fipronil with the increase in dilution. For phoxim, some outliers, with apparently lower sensitivity, were observed particularly in one farm, suggesting that a resistance phenomenon was triggered in this mite population. For this reason, it is necessary to underline the importance of the utilization of authorized products at correct dosages and times of treatment and the need for alternative molecules to avoid the onset of drug resistance phenomena. The poultry red mite Dermanyssus gallinae is the most important blood-sucking ectoparasite in egg-laying hen facilities. The aim of this study was to evaluate the in vitro acaricidal activity of different concentration of authorized (phoxim, ByeMite®, 500 mg/mL) and unauthorized (fipronil, Frontline® 250 mg/100 mL spray) molecules on 14 field isolates of D. gallinae collected from different ornamental poultry farms from different Italian regions. The sensitivity test was performed by contact exposure to four concentrations of each insecticide diluted at 1:5 (10,000-2000-400-80 ppm for phoxim, 500-100-20-4 ppm for fipronil) on a filter paper. The effectiveness of the treatment was significantly (p < 0.0001) associated with the dose of the pesticide used. Considering the mean lethality, phoxim has greater efficacy compared to fipronil (p < 0.001). A great variability of lethality rate was observed with the increase in fipronil dilution; conversely, for phoxim, some outliers were observed, particularly in one farm, suggesting the hypothesis that a certain degree of resistance in the mite population could occur possibly as a consequence of the continual contact with the molecule. This underlines the importance of the use of licensed products administered at correct dosages and the need for alternative molecules to avoid the onset of drug resistance phenomena. [ABSTRACT FROM AUTHOR]

BackgroundNorthern fowl mites (Ornithonyssus sylviarum) are obligate hematophagous ectoparasites of both feral birds and poultry, particularly chicken layers and breeders. They complete their entire life-cycle on infested birds while feeding on blood. Infestations of O. sylviarum are difficult to control and resistance to some chemical classes of acaricides is a growing concern. The contact susceptibility of O. sylviarum to a new active ingredient, fluralaner, was evaluated, as well as other compounds representative of the main chemical classes commonly used to control poultry mite infestations in Europe and the USA.MethodsSix acaricides (fluralaner, spinosad, phoxim, propoxur, permethrin, deltamethrin) were dissolved and serially diluted in butanol:olive oil (1:1) to obtain test solutions used for impregnation of filter paper packets. A carrier-only control was included. Thirty adult northern fowl mites, freshly collected from untreated host chickens, were inserted into each packet for continuous compound exposure. Mite mortality was assessed after incubation of the test packets for 48 h at 75% relative humidity and a temperature of 22 °C.ResultsAdult mite LC50 /LC99 values were 2.95/8.09 ppm for fluralaner, 1587/3123 ppm for spinosad, 420/750 ppm for phoxim and 86/181 ppm for propoxur. Permethrin and deltamethrin LC values could not be calculated due to lack of mortality observed even at 1000 ppm.ConclusionsNorthern fowl mites were highly sensitive to fluralaner after contact exposure. They were moderately sensitive to phoxim and propoxur, and less sensitive to spinosad. Furthermore, the tested mite population appeared to be resistant to the pyrethroids, permethrin and deltamethrin, despite not being exposed to acaricides for at least 10 years.

The black cutworm, Agrotis ipsilon (Lepidoptera: Noctuidae), is an important agricultural pest. Phoxim is an organophosphate insecticide that has been widely used to control A. ipsilon. The extensive application of phoxim has resulted in a reduction in phoxim susceptibility in A. ipsilon. However, the molecular mechanisms underlying phoxim tolerance in A. ipsilon remain unclear. In this work, we report the involvement of AiGSTz1, a zeta class glutathione S -transferase, in phoxim tolerance in A. ipsilon. Exposure to a sublethal concentration (LC 50) of phoxim dramatically upregulated the transcription level of the AiGSTz1 gene in A. ipsilon larvae, and this upregulation might be caused by phoxim-induced oxidative stress. The recombinant AiGSTz1 protein expressed in Escherichia coli was able to metabolize phoxim. Furthermore, AiGSTz1 displayed antioxidant activity to protect against oxidative stress. Knockdown of AiGSTz1 by RNA interference significantly increased the mortality rate of A. ipsilon larvae in response to phoxim. In addition, the transcription factor AiCncC can bind to the cap 'n' collar isoform C: muscle aponeurosis fibromatosis (CncC:Maf) binding site in the putative promoter of the AiGSTz1 gene. Silencing of AiCncC resulted in a dramatic downregulation of AiGSTz1. These results indicated that AiGSTz1 is involved in phoxim tolerance and is potentially regulated by AiCncC. These findings provide valuable insights into the defense mechanisms used by A. ipsilon against phoxim. [Display omitted] • A zeta class GST from black cutworms has been characterized. • The transcription of AiGSTz1 is induced by phoxim exposure. • AiGSTz1 can deplete phoxim and protect against oxidative stress. • Knockdown of AiGSTz1 increases the susceptibility of insects to phoxim. • AiGSTz1 is potentially regulated by the transcription factor AiCncC. [ABSTRACT FROM AUTHOR]

With continuous development of pesticide dosage forms, emulsifiable concentrates using large amounts of organic solvents are gradually obsoleted. Nanoemulsions with high water content have been developed and the preparation processes also evolved, but these processes still exist some problems, such as poor controllability and high energy consumption. Microfluidic is a controllable nanoemulsion preparation system which mainly applied to pharmaceutical synthesis. In this study, the pesticide phoxim nanoemulsion was prepared by microfluidic technology. The optimized formulation of phoxim nanoemulsion was composed of Tween 80 and pesticide emulsifier 500 as surfactant, hexyl acetate as oil, and n-propanol as co-surfactant. Moreover, when the flow rates of water and oil in the microfluidic system were adjusted to 5 μL/min and 20 μL/min, phoxim nanoemulsion was obtained with a cloud point/boiling point of 109 °C, a particle size of 21.5 ± 0.8 nm and a potential value of − 18.7 ± 0.6 mV. Furthermore, the nanoemulsion had a rapid release effect in vitro which could be fitted by the Ritger-Peppas model. The feeding toxicity of the phoxim nanoemulsion was higher than that of commercial formulation while the contact killing effect was higher than that of the active ingredient. Therefore, pesticide dosage was reduced and the insecticidal effect was enhanced by using phoxim nanoemulsions. These results also confirm the potential of microfluidics as a green process to produce pesticide nanoemulsions. [ABSTRACT FROM AUTHOR]

The histidine functionalized graphene quantum dots （His-GQDs） react with ruthenium trichloride to form a stable ruthenium complex. This complex is treated in a N2 atmosphere at 600 ℃ for 1 h to obtain a ruthenium-graphene quantum dot composite （Ru-His-GQD）. Studies have shown that Ru-His-GQD has a three-dimensional structure. The diameter of ruthenium nanoparticles is between 40 and 60 nm. Ru-His-GQD is rich in functional groups and has high oxidase-like activity. Based on Ru-His-GQD catalyzed oxidation of 3，3’，5，5’-tetramethylbenzidine （TMB） to produce blue compounds， a photometric method for the determination of phoxim in carrots is established. Phoxim can inhibit the activity of Ru-His-GQD oxidase， resulting in a decrease in the absorbance of the blue compound. When the concentration of phoxim is between 30～240 μg/L， the absorbance of the oxidation product of TMB at 652 nm decreases linearly with the increase of phoxim concentration. The detection limit of the method reaches 7.33 ng/mL （S/N=3）， and the sensitivity is higher than those in literature. It has been successfully applied to the detection of phoxim in carrots. [ABSTRACT FROM AUTHOR]

A new method to synthesize phoxim.

[Objectives] The paper was to verify the field efficacy of 1% bifenthrin • thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato. [Methods] A total of 4 field trials were conducted in Guangdong Province, including 1% bifenthrin • thiamethoxam GR applied at the doses of 3, 4 and 5 kg/667 m2, and 3% phoxim GR applied at the dose of 4 kg/667 m2. [Results] 1% Bifenthrin • thiamethoxam GR applied at the dose of 5 kg/667 m2 had excellent control effects on sweet potato weevil, with an average control effect of 77.60%, which was significantly higher than that of 3% phoxim GR applied at the dose of 4 kg/667 m2(48. 52%). And the average yield increase rate of sweet potato treated with 1% bifenthrin • thiamethoxam GR reached 24.79%, significantly higher than 12. 37% in the control group. [Conclusions] 1% Bifenthrin • thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5 - 7 d after planting, and the recommended dosage is 5 kg/667 m2, which will have good control effect on sweet potato weevil and increase the yield of sweet potato. [ABSTRACT FROM AUTHOR]

The efficacy of phoxim in treating bacterial sepsis in silver carp is significant, yet its underlying mechanism remains elusive. This study aimed to establish a model of Aeromonas veronii infection in silver carp and subsequently treat the infected fish with 10 μg/L phoxim. Kidney and intestine samples from silver carp were collected for transcriptome analysis and assessment of intestinal microbial composition, with the aim of elucidating the mechanism underlying the efficacy of phoxim in treating bacterial sepsis in silver carp. The results of transcriptome and intestinal microbial composition analysis of silver carp kidney indicated that A. veronii infection could up-regulate the expression of il1β , il6 , nos2 , ctsl , casp3 et al., which means, signifying that the kidney of silver carp would undergo inflammation, induce apoptosis, and alter the composition of intestinal microorganisms. Phoxim immersion might enhance the energy metabolism of silver carp and change its intestinal microbial composition, potentially elevating the antibacterial infection resistance of silver carp. These findings may contribute to an understanding of how phoxim can effectively treat bacterial sepsis in silver carp. • The phoxim exposure can induce alterations in the intestinal microorganism composition of silver carp. • Aeromonas veronii can induce renal inflammation in silver carp and alter the composition of intestinal microorganisms. • The ability of silver carp to resist Aeromonas veronii infection may be enhanced by phoxim. [ABSTRACT FROM AUTHOR]

Malathion, phoxim, and thiram are organophosphates and organosulfur pesticides widely used in agricultural products. The residues of these pesticides present a direct threat to human health. Rapid and on-site detection is critical for minimizing such risks. In this work, a simple approach was introduced using a flexible surface-enhanced Raman spectroscopy (SERS) substrate. The prepared Ag nanoparticles-polydimethylsiloxane (AgNPs-PDMS) substrate showed high SERS activity, good precision (relative standard deviation = 5.33%), and stability (30 days) after optimization. For target pesticides, the linear relationship between characteristic SERS bands and concentrations were achieved in the range of 10~1000, 100~5000, and 50~5000 μg L−1 with LODs down to 3.62, 41.46, and 15.69 μg L−1 for thiram, malathion, and phoxim, respectively. Moreover, SERS spectra of mixed samples indicated that three pesticides can be identified simultaneously, with recovery rates between 96.5 ± 3.3% and 118.9 ± 2.4%, thus providing an ideal platform for detecting more than one target. Pesticide residues on orange surfaces can be simply determined through swabbing with the flexible substrate before acquiring the SERS signal. This study demonstrated that the prepared substrate can be used for the rapid detection of pesticides on real samples. Overall, this method greatly simplified the pre-treatment procedure, thus serving as a promising analytical tool for rapid and nondestructive screening of malathion, phoxim, and thiram on various agricultural products.

The poultry red mite Dermanyssus gallinae is the most important blood-sucking ectoparasite in egg-laying hen facilities. The aim of this study was to evaluate the in vitro acaricidal activity of different concentration of authorized (phoxim, ByeMite®, 500 mg/mL) and unauthorized (fipronil, Frontline® 250 mg/100 mL spray) molecules on 14 field isolates of D. gallinae collected from different ornamental poultry farms from different Italian regions. The sensitivity test was performed by contact exposure to four concentrations of each insecticide diluted at 1:5 (10,000-2000-400-80 ppm for phoxim, 500-100-20-4 ppm for fipronil) on a filter paper. The effectiveness of the treatment was significantly (p < 0.0001) associated with the dose of the pesticide used. Considering the mean lethality, phoxim has greater efficacy compared to fipronil (p < 0.001). A great variability of lethality rate was observed with the increase in fipronil dilution; conversely, for phoxim, some outliers were observed, particularly in one farm, suggesting the hypothesis that a certain degree of resistance in the mite population could occur possibly as a consequence of the continual contact with the molecule. This underlines the importance of the use of licensed products administered at correct dosages and the need for alternative molecules to avoid the onset of drug resistance phenomena.

2 kinds of bacteria, named XLL-M04 and XLLM12, were isolated from the soil, which could degrade phoxim effectively. XLL-M04 and XLL-M12 were identified as Bacillus cohnii and Bacillus firmus. The degradation efficiency of 10mg/L of phoxim by XLL-M04 could reach about 99.0% in 7d, and the strain XLL-M12 could reach 98.0% under the same conditions. Both strain XLL-M04 and strain XLL-M12 could also effectively degrade chlorpyrifos, malathion, parathion and fenitrothion. In addition, strain XLL-M04 and strain XLL-M12 had been successfully developed into a live microbial agent that could be used to degrade phoxim residue. These results suggest that strain XLL-M04 and strain XLL-M12 can be used for the bioremediation of phoxim or other organophosphorus pesticides contamination. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Fleas (Ceratophyllus sciurorum) are common on farmed mink in Denmark. When present, the fleas have a negative impact on the health of the farmed mink and are of nuisance for farm staff. Severe infestations of fleas cause anemia, poor growth and may result in death of mink kits. Changed behavior of the dams is also observed. Further it has been demonstrated that the fleas are vectors of Aleutian disease virus. Flea control is based on use of a few insecticides and resistance has been reported against permethrin. There is thus a need for new flea control products. In this blinded, randomized clinical trial according to GCP standard, phoxim spray and bendiocarb powder for flea control on mink farms were investigated. Results Both the phoxim spray solution and bendiocarb powder were found to be efficient for the control of C. sciurorum fleas on farmed mink. Phoxim treatments reduced the number of fleas by 98.4% and the bendiocarb treatments reduced the number of fleas by 99.0% in the mink nest boxes when compared to counts in controls. No clinical signs were observed post treatment. Conclusions The study demonstrated that phoxim sprayed on the animals and the use of bendiocarb powder in the nest box material were highly efficient for the control of the C. sciurorum fleas on farmed mink. Both products were safe to use at the recommended dose rate. Both compounds are recommended to be integrated in a new farm management plan suggested here.

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to overuse and terrestrial input, there are large quantities of phoxim and prometryne residues in some aquatic environments. In the present study, the effects of these compounds on Penaeus vannamei hepatopancreas were analysed at the transcriptome level to investigate toxicity in this nontarget aquaculture organism. Twelve normalised cDNA libraries were constructed using RNA from phoxim and prometryne treatment groups, and an untreated control group. A total of 667,750,902 clean reads were obtained. Analysis of differentially expressed genes (DEGs) identified 449 in control vs phoxim groups, 185 in control vs prometryne groups, and 183 in prometryne vs phoxim groups. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, arachidonic acid metabolism, pancreatic secretion, linoleic acid metabolism, and beta-alanine metabolism pathways were significantly enriched in control vs phoxim groups. In control vs prometryne groups, lysosome, pentose and glucuronate interconversion, antigen processing and presentation, and glycosaminoglycan degradation pathways were significantly enriched. In prometryne vs phoxim groups, protein digestion and absorption, extracellular matrix (ECM)-receptor interaction, PI3K-Akt signalling, cell adhesion molecule (CAM), AGE-RAGE signalling related to diabetic complications, focal adhesion, and renin secretion pathways were significantly enriched. In further detailed analysis, glutathione S-transferase (GST), glutathione peroxidase and basic phospholipase A2 were downregulated in the phoxim treatment group, indicating that phoxim damaged hepatopancreas. Upregulation of phospholipase A2 (secretory phospholipase A2-like) indicates possible inflammatory pathological injury to hepatopancreas caused by phoxim. Meanwhile, downregulation of CD63 indicates that prometryne affect the immune system. • This study explored the toxicity mechanism of phoxim and prometryne on shrimp hepatopancreas. • Prometryne affect the immune system of shrimp. • After treatment of phoxim, GST, glutathione peroxidase, and basic phospholipase A2 were downregulated in shrimp. • The damage of phoxim was larger than prometryne on shrimp. [ABSTRACT FROM AUTHOR]

To investigate the residual behaviors of three organophosphorus pesticides in the cultivation of Agaricus bisporus, field trials were conducted by applying diazinon, chlorpyrifos and phoxim into the culture media (soil and substrates). By optimizing the pretreatment method and instrument conditions, determination method of three organophosphorus pesticide in mushroom, soil and substrates using liquid chromatography-tandem mass spectrometry was established. Samples were extracted with acetonitrile, purified by QuEChERS and detected with UPLC-MS/MS. In mushroom, soil and cultivation substrates, Recoveries of diazinon at the spiked levels of 0.000 3, 0.003, 0.1 mg/kg and the recoveries of chlorpyrifos and phoxim at the spiked levels of 0.000 6, 0.006, and 0.1 mg/kg, were 76%- 108%, and the relative standard deviation was 2.2%-13%. The limits of detection (LOD) of diazinon, chlorpyrifos and phoxim were 0.000 1, 0.000 2, 0.000 2 mg/kg, respectively, and the limits of quantitation (LOQ) were 0.000 3, 0.000 6, 0.000 6 mg/kg, respectively. At all application rates, three pesticides dissipated following the first-order degradation kinetics. The dissipation half-lives of diazinon, chlorpyrifos and phoxim in cultivation substrates were 5.2 d, 10.6 d, 13.6 d and 5.6 d, 11.4 d, 12.3 d and those in soil were 25.9 d, 41.7 d, 27.2 d and 41.7 d, 48.1 d, 36.8 d, respectively. The dissipation of three pesticides in soil was faster than that in the cultivation substrates. Chlorpyrifos residue in mushroom fruits was up to 0.014 mg/kg at the application rate of 10 mg/kg, which exceeded the European maximum residue limits standard (MRL). The others were lower than the Japanese, European and America MRL values. [ABSTRACT FROM AUTHOR]

Silkworm (Bombyx mori) is an important economic insect. Bombyx mori , which is exposed to sublethal doses of pesticides, has a low or no mortality rate, while it is susceptible to infections triggered by foreign pathogens. The immune regulatory mechanism of silkworms caused by trace pesticides still remains unclear. The midgut is the major organ of silkworm for digestion and nutrient absorption, and it plays a critical defensive role against pathogens. In the present study, the silkworm was susceptible to Enterobacter cloacae sp. (E. cloacae) after exposure to sublethal dose of phoxim. The body weight and survival rate of the phoxim- E. cloacae co-treatment group were significantly decreased after 120 h of treatment compared with the phoxim treatment group. The immune responses and expressions of immune-related genes were dysregulated in the midgut of silkworm following exposure to phoxim. Digital gene expression (DGE) analysis revealed that 44 immune response-related and immune defense-related genes were differentially expressed. qRT-PCR results indicated that the transcriptional levels of antimicrobial peptide genes Bmdefensin1 , BmcecA , Bmglv1 , Bmglv2 , Bmmoricin and BmmoricinB3 were down-regulated by 0.77-, 0.37-, 0.05-, 0.19-, 0.34- and 0.54-fold, respectively. The transcriptional levels of Toll signaling pathway genes Bmcactus , Bmspatzle and Bmrel were down-regulated by 0.4-, 0.37- and 0.96-fold, respectively. Peritrophic membrane (PM) protein-related genes BmCBP-02 , BmPM-41 , BmPM-43 and BmCDA7 were down-regulated by 0.18-, 0.02-, 0.66- and 0.16-fold, respectively. The expressions of Toll signaling pathway genes were down-regulated at 48 h and 72 h. Immune deficiency (IMD) and Janus kinase and signal transducer and activator of transcription (JAK/STAT) signaling pathway genes were dysregulated after phoxim exposure. These results indicated that phoxim might cause damage to the PM and reduce the immune response of the silkworm, leading to susceptibility of silkworm to disease and damage from foreign pathogens. Unlabelled Image • Phoxim and Enterobacter cloacae co-treatment enhanced toxic effects on silkworms. • Phoxim dysregulated the expression of Toll, IMD and JAK/STAT signaling pathway genes. • Phoxim damaged immune defense of midgut, inducing silkworm sensitivity to pathogens. [ABSTRACT FROM AUTHOR]

Abstract Background Northern fowl mites (Ornithonyssus sylviarum) are obligate hematophagous ectoparasites of both feral birds and poultry, particularly chicken layers and breeders. They complete their entire life-cycle on infested birds while feeding on blood. Infestations of O. sylviarum are difficult to control and resistance to some chemical classes of acaricides is a growing concern. The contact susceptibility of O. sylviarum to a new active ingredient, fluralaner, was evaluated, as well as other compounds representative of the main chemical classes commonly used to control poultry mite infestations in Europe and the USA. Methods Six acaricides (fluralaner, spinosad, phoxim, propoxur, permethrin, deltamethrin) were dissolved and serially diluted in butanol:olive oil (1:1) to obtain test solutions used for impregnation of filter paper packets. A carrier-only control was included. Thirty adult northern fowl mites, freshly collected from untreated host chickens, were inserted into each packet for continuous compound exposure. Mite mortality was assessed after incubation of the test packets for 48 h at 75% relative humidity and a temperature of 22 °C. Results Adult mite LC50 /LC99 values were 2.95/8.09 ppm for fluralaner, 1587/3123 ppm for spinosad, 420/750 ppm for phoxim and 86/181 ppm for propoxur. Permethrin and deltamethrin LC values could not be calculated due to lack of mortality observed even at 1000 ppm. Conclusions Northern fowl mites were highly sensitive to fluralaner after contact exposure. They were moderately sensitive to phoxim and propoxur, and less sensitive to spinosad. Furthermore, the tested mite population appeared to be resistant to the pyrethroids, permethrin and deltamethrin, despite not being exposed to acaricides for at least 10 years.

The existence of a temperature effect of insecticides frustrated the control of the green plant bug Apolygus lucorum (Meyer-Dür). Previous studies mostly focused on the application of insecticides, but the underlying mechanism remains incompletely understood. Here, we report a transcriptome profiling of A. lucorum treated by three kinds of temperature coefficient insecticides (TCIs) (positive TCI: imidacloprid, negative TCI: b-cypermethrin and non-effect TCI: phoxim) at 15 °C, 25 °C and 35 °C by using next- and third-generation RNA-Seq methods. A total of 34,739 transcripts were annotated from 277.74 Gb of clean data. There were more up-regulated transcripts than down-regulated transcripts in all three kinds of TCI treatments. Further Venn diagrams indicate the regulatory transcripts and regulatory modes were different at the three temperatures. The responses to imidacloprid involved more detox and stress response transcripts such as cytochrome P450 (CYP450), carboxylesterase (CarE) and catalase (CAT) at 35 °C, which was the case for beta-cypermethrin at 15 °C. UDP-glucuronyltransferase (UGT) and heat shock protein (HSP) transcripts were heavily involved, and thus deserve particular note in the temperature effect of insecticides. This high-confidence transcriptome atlas provides improved gene information for further study on the insecticide temperature effect related physiological and biochemical processes of A. lucorum. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• This work provides a novel plasma activated water strategy for reduction of pesticide. • The acidic environment and oxidation capacity are beneficial to the phoxim reduction. • Plasma activated water treatment will not significantly affect the quality of grapes. • One possible degradation pathway of phoxim is proposed. • The strategy provides a potential possibility for large-scale industrial production. In this study, we propose a novel strategy, plasma activated water (PAW) to reduce pesticide residues on agricultural products. To validate its feasibility and effectiveness, we employee high-performance liquid chromatography (HPLC) to detect phoxim on grapes. HPLC results suggest that the reduction of phoxim on grapes achieve 73.60% after treated 10 min by PAW prepared 30 min, and the concentration of phoxim decreased significantly (p < 0.05) with the preparation time of PAW. Furthermore, HPLC-MS analysis shows that the reduction effect of phoxim by PAW is dominated by the degradation of phoxim. Combined with analyzing the physicochemical properties of PAW, one possible degradation pathway is proposed under the present experimental conditions, mediated by reactive oxygen and nitrogen species. The acidic environment (pH < 3) and high oxidation capacity (ORP > 500 mV) are suggested to be a benefit to the reduction of phoxim. Besides, the experimental results regarding color, firmness, sugar, vitamin C, and superoxide dismutase of grapes demonstrate that the PAW treatment will not significantly affect the quality of grapes. In conclusion, phoxim pesticide residues on grapes could be effectively reduced by the PAW strategy and without a significant (p < 0.05) effect on grapes quality. [ABSTRACT FROM AUTHOR]

• A novel MIP/perovskite CsPbBr 3 QDs fluorescence sensor for phoxim detection. • A siloxane functional monomer with two kinds of functional groups has been synthesized. • The MIP/QDs were synthesized by slowly hydrolyzing the organosilicon monomers in situ. • The QDs were encapsulated in an imprinted silica matrix, which improved the stability of the QDs. In spite of the high-brightness of perovskite quantum dots (QDs), their instability and sensitive to oxygen and moisture are still major challenges that obstruct their analytical applications. This work demonstrates the fabrication and application of perovskite CsPbBr 3 QDs embedded in a molecularly imprinted polymer (MIP) for specific and sensitive detection of phoxim in real samples. CsPbBr3 QDs were obtained via a simple and convenient hot injection method. Based on the chemical structure of phoxim, we designed and synthesized a siloxane functional monomer with multiple functional groups to allow various types of interactions with phoxim. Next, the MIP/QDs composites were synthesized by slowly hydrolyzing the organosilicon monomers in situ. The obtained MIP/QDs composites possessed excellent selectivity for phoxim, and the imprinting factor of the optimized MIP/QDs was 3.27. Compared with previous studies regarding the detection of organophosphorus pesticides, the MIP/QDs fluorescence sensor exhibited high sensitivity and specificity. Under optimal conditions, the fluorescence quenching of the MIP/QDs had a good linear correlation for phoxim in the concentration range of 5–100 ng/mL, and with a limit of detection of 1.45 ng/mL. Finally, the method was used for the detection of phoxim in potato and soil samples, achieving recoveries of 86.8–98.2%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Recombinant protein SlGSTD3 and SlGSTD4 in S. litura could metabolize phoxim and chlorpyrifos. • Recombinant vector SlGSTD3 and SlGSTD4 in S. litura both showed antioxidant activity to CHP. • The 3D structure of SlGSTD3 and SlGSTD4 in S. litura could bind to phoxim and chlorpyrifos. Glutathione S -transferases (GSTs) is one of the main detoxification enzyme systems in insects and play important roles in insecticide resistance by direct metabolism, sequestration and antioxidant activity. Several GSTs genes in Spodoptera litura , a polyphagous agricultural pest, have been demonstrated to be overexpressed and involved in organophosphates and pyrethroids resistance. Previous studies have indicated the significant overexpression of two delta class GSTs genes (SlGSTd3 and SlGSTd4) in organophosphates and pyrethroids resistant populations. Here, they were heterologous expressed, and their metabolism activity and antioxidant activity were determined. Results indicated that the recombinant protein SlGSTD3 and SlGSTD4 both showed metabolism activity to phoxim and chlorpyrifos, but not to fenvalerate, cyhalothrin or beta cypermethrin. The metabolism activity of SlGSTD3 to phoxim and chlorpyrifos is higher than that of SlGSTD4. The recombinant vector of SlGSTD3 and SlGSTD4 both showed antioxidant activity after exposure to cumene hydroperoxide. Further modeling and docking analysis indicated that the 3D structure of SlGSTD3 and SlGSTD4 were well shaped for phoxim and chlorpyrifos, and the binding affinity for phoxim was stronger than that of chlorpyrifos. Our work provides evidence that SlGSTd3 and SlGSTd4 both play roles in phoxim and chlorpyrifos resistance in S. litura. [ABSTRACT FROM AUTHOR]

The black cutworm Agrotis ipsilon is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control A. ipsilon . When phoxim is extensively applied, the susceptibility of A. ipsilon to insecticide is reduced. However, the mechanisms of tolerance of A. ipsilon to phoxim remain unclear. Herein, we report that an epsilon class glutathione S -transferase, AiGSTE1, confers phoxim tolerance in A. ipsilon . Exposure to a sublethal concentration (LC 50 ) of phoxim caused oxidative stress and activated the transcription of AiGSTe1 genes in A. ipsilon larvae. Recombinant AiGSTE1 expressed in Escherichia coli could metabolize phoxim. Furthermore, E. coli cells overexpressing AiGSTE1 displayed significant tolerance to oxidative stress. Knockdown of AiGSTe1 by RNA interference significantly increased the mortality of A. ipsilon larvae to phoxim. These results demonstrate that AiGSTE1 confers phoxim tolerance in A. ipsilon by metabolizing the insecticide and preventing phoxim-induced oxidative stress.

Dermanyssus gallinae (De Geer, 1778) is a major problem for the poultry industry worldwide, as it negatively affects virtually all kinds of rearing systems. Therefore, the control of infestation has become a routine process, and its economic cost is constantly increasing. Until now, most of the control strategies have relied on the use of synthetic chemical drugs, but their efficacy is often questioned by the emergence and diffusion of resistant mite populations. With this in mind, the efficacy of λ-cyhalothrin, amitraz, and phoxim has been verified by testing them against 86 mite populations collected from the same number of poultry farms in Italy from 2008 to 2015. Assays were performed according to the filter paper method using the recommended, half, quarter, double and quadruple doses. The results showed that phoxim and amitraz were the most effective acaricides (median efficacies 80.35% and 80.83%, respectively), but amitraz exhibited a sharp fall in its efficacy during 2011 and 2012, while phoxim maintained its high effectiveness up to 2015, when it dropped. The overall median efficacy of λ-cyhalothrin was 58.33%. The data also highlighted the importance of the use of the right concentration, as an increase in dosage was not always useful against resistant populations, while its reduction also diminished efficacy, simultaneously increasing the risk for the development of resistance. [ABSTRACT FROM AUTHOR]

Abstract: Silk gland is a major organ of Bombyx mori for the synthesis and secretion of silk protein. Phoxim exposure can be toxic to B. mori and causes a decrease of fibroin synthesis, finally affecting the silk production in industry. To study the mechanism of metabolism and detoxification of silk gland under phoxim exposure, we measured the residual quantity of phoxim in silk gland and hemolymph after phoxim exposure, and the detoxifying enzymes-related genes and enzyme activity were also investigated. Results indicated that the residual amount of phoxim existed up to 24 h in silk gland compared with that in hemolymph, suggesting that phoxim can accumulate in the silk glands within a certain time course. The transcriptional levels of PI3K/Akt genes, including Akt, Tor1, p70s6k and 4e-bp , were up-regulated by 6.919, 1.358, 10.766 and 7.708-fold, respectively. The expression of two downstream genes ( CncC and Keap1 ) was up-regulated by 1.939 and 3.373-fold, respectively. In addition, the transcriptional levels of detoxification-related genes including CYP6AB, CYP3 06A , CarE2, GST1 and GSTd1 were up-regulated by 1.731, 1.221, 1.366, 1.376 and 6.591-fold, respectively. The enzymatic activity of CYP450, CarE and GST were increased over time. These results provided possible insights into the injury of silk gland and the transcriptional response to detoxifying enzymes-related genes in silkworm after phoxim exposure. [ABSTRACT FROM AUTHOR]

Phoxim is an organic phosphorus pesticide that remains easily in the environment, such as human food and animal feed. The objective of this study was to explore the effect of vitamin E on phoxim-induced oxidative stress in the intestinal tissues of Sprague-Dawley (SD) rats. Forty-eight Sprague-Dawley rats were randomly assigned to a control group and three treatment groups: treatment group 1 (phoxim: 20 mg/kg·BW), treatment group 2 (phoxim: 180 mg/kg·BW), and treatment 3 (vitamin E + phoxim: 200 mg/kg·BW + 180 mg/kg·BW). Phoxim was given by gavage administration once a day for 28 days. The results showed that phoxim significantly reduced jejunum villus height in rats (P < 0.05), and decreased the mRNA expression of junction protein genes of rats, including Occlidin and Claudin-4 (P < 0.05). Phoxim reduced GSH content and T-AOC level in the intestinal mucosa (P < 0.05). The mRNA expression levels of oxidative stress-related genes (Nrf2 and GPx2) were decreased. The mRNA expression of SOD was significantly increased. In addition, phoxim increased the level of interleukin-6 (IL-6) in jejunum mucosa and significantly reduced the level of IL-8 in ileum mucosas, while significantly increased TNF-α secretion. The mRNA expression levels of IL-1β, IL-6, and IL-8 were significantly decreased, and mRNA expression of TNF-α was significantly increased (P < 0.05). Phoxim also increased the DNA expression of total cecal bacteria and Escherichia coli, inhibited the DNA expression of Lactobacillus and destroyed the intestinal barrier. Two hundred milligrams per kilogram BW vitamin E reduced the effect of phoxim on intestinal structure, alleviated the oxidative stress in intestinal tissue, and decreased the level of TNF-α. The mRNA expressions of antioxidative stress genes (SOD and GPx2) were significantly increased. The DNA expression level of Lactobacillus was significantly increased. In conclusion, vitamin E helped reduce the toxicity of organophosphate pesticides, such as phoxim on rat intestinal tissue. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, Lycii Fructus as raw materials for green synthesis of fluorescent carbon dots (CDs) reduce AgNO 3 . The CDs-AgNPs were synthesized by one-step method. CDs were applied to stabilize AgNPs due to abundant functional groups on the surface of CDs. In presence of phoxim, the dispersed CDs-AgNPs get aggregated and the absorption peak with red shift from 400 nm to 525 nm, resulting in the color changed from yellow to red. Under optimized conditions, the absorbance ratio at A 525 nm /A 400 nm was related linearly to the concentrations of phoxim in the range of 0.1–100 μM. The detection limit was calculated to 0.04 μM, which is lower than maximum residue limits of phoxim in samples in China. The colorimetric sensor was successfully utilized to monitoring phoxim in environmental and fruit samples with good recoveries ranges from 87% to 110.0%. These results showed the sensor had a promising application prospect in real samples. [ABSTRACT FROM AUTHOR]

Folate metabolism pathway is mainly associated with syntheses of nucleic acids and proteins as well as DNA methylation and repair. Cytoplasmic C 1 tetrahydrofolate (C 1 -THF) synthase is a central enzyme in folate metabolism and plays an important role in C 1 -THF conversion. The full-length sequence of silkworm ( Bombyx mori ) cytoplasmic C 1 -THF synthase ( Bm C 1 -THF synthase) gene including an open reading frame (ORF) of 932 amino acid residues was cloned. Phylogenetic analysis indicated that Bm C 1 -THF synthase shares 84% and 81% identity with C 1 -THF synthase of Papilio Xuthus and Danaus plexippus , respectively. Conserved sequence analysis showed that the 330 to 710 amino acid residues of Bm C 1 -THF synthase were highly conserved among various organisms. Recombinant Bm C 1 -THF synthase protein with a molecular weight of about 105.5 kDa was expressed in E. coli cells and identified using SDS-PAGE and western blot analysis. The expression of Bm C 1 -THF synthase gene in eight silkworm tissues revealed that Bm C 1 -THF synthase gene is widely expressed in various tissues of silkworm and highly expressed in the fat body. The expression characteristics of Bm C 1 -THF synthase gene in response to oxidative stress were conducted under phoxim and high temperature (30 °C) exposure. The results showed that the transcriptional level of Bm C 1 -THF synthase gene was upregulated by 3.435-fold and 6.845-fold after phoxim and high temperature (30 °C) exposure, respectively, indicating that Bm C 1 -THF synthase gene may play a significant role in response of silkworm to oxidative stresses. [ABSTRACT FROM AUTHOR]