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Industrial fermentation applications typically require enzymes that exhibit high stability and activity at high temperatures. However, efforts to simultaneously improve these properties are usually limited by a trade‐off between stability and activity. This report describes a computational strategy to enhance both activity and thermal stability of the mesophilic organophosphate‐degrading enzyme, methyl parathion hydrolase (MPH). To predict hotspot mutation sites, we assembled a library of features associated with the target properties for each residue and then prioritized candidate sites by hierarchical clustering. Subsequent in silico screening with multiple algorithms to simulate selective pressures yielded a subset of 23 candidate mutations. Iterative parallel screening of mutations that improved thermal stability and activity yielded, MPHase‐m5b, which exhibited 13.3 °C higher Tm and 4.2 times higher catalytic activity than wild‐type (WT) MPH over a wide temperature range. Systematic analysis of crystal structures, molecular dynamics (MD) simulations, and quantum mechanics/molecular mechanics (QM/MM) calculations revealed a wider entrance to the active site that increased substrate access with an extensive network of interactions outside the active site that reinforced αβ/βα sandwich architecture to improve thermal stability. This study thus provides an advanced, rational design framework to improve efficiency in engineering highly active, thermostable biocatalysts for industrial applications. [ABSTRACT FROM AUTHOR]

Organophosphate pesticides are widely used; however, their use is limited due to neurotoxicity and, to a lesser extent, cardiotoxicity in humans. Given the high energy demands of cardiac muscle, which is characterized by a dense population of mitochondria, any damage to these organelles can exacerbate cardiotoxicity. This study aims to elucidate whether the cardiotoxic effects of organophosphate pesticides originate from mitochondrial dysfunction. To investigate this, in silico toxicogenomic analyses were performed using various tools, such as the Comparative Toxicogenomic Database, GeneMANIA, STRING, and Cytoscape. Results revealed that 11 out of the 13 WHO-recommended Class Ia organophosphate pesticides target genes associated with cardiotoxicity. Notably, three of these genes were mitochondrial, with catalase (CAT) being the common differentially expressed gene among parathion, methyl parathion, and phorate. Furthermore, protein-protein interaction analysis indicated a strong association between CAT and superoxide dismutase 2, mitochondrial (SOD2). Subsequently, isolated heart mitochondria were utilized to assess CAT and superoxide dismutase (SOD) activities in vitro. The findings demonstrated that at a concentration of 7.5 ng/µL, both methyl parathion and phorate significantly decreased CAT activity by approximately 35%. Moreover, phorate reduced total SOD and SOD2 activities by 17% and 19%, respectively, at the same concentration. In contrast, none of the three organophosphate pesticides induced the opening of the mitochondrial permeability transition pore. These results suggest that the reduction in CAT and SOD2 activities, critical antioxidant enzymes, leads to the accumulation of reactive oxygen species within mitochondria, ultimately resulting in mitochondrial damage. This mechanism likely underlies the observed cardiotoxicity induced by these organophosphate pesticides. [ABSTRACT FROM AUTHOR]

In this study, type-II heterojunction WO 3 /BaTiO 3 and Z-scheme WO 3 /SrTiO 3 or WO 3 /Ba 0.5 Sr 0.5 TiO 3 nanocomposite photocatalysts were constructed for photodegradation of organic pollutants in wastewater under visible light. The photocatalytic performance of three WO 3 /titanate systems were estimated. Some influencing factors such as molar ratio of WO 3 and titanates, light irradiation time, catalyst dose, and initial concentration of organic pollutants on the photocatalytic activity were investigated. The stability and reusability of three WO 3 /titanates systems were examined. Moreover, the production of some radicals in the three WO 3 /titanates photocatalytic systems was demonstrated, and the three WO 3 /titanates photocatalytic reaction mechanisms were compared. The results reveal that the configurations of WO 3 /titanates photocatalytic systems are transformed from type-II heterojunction WO 3 /BaTiO 3 with lower activity to Z-scheme WO 3 /SrTiO 3 and WO 3 /Ba 0.5 Sr 0.5 TiO 3 with higher activity via the change of titanates. The WO 3 /titanate nanocomposites show higher photocatalytic activity at 3.0:1.0 M ratio of WO 3 and titanates, and WO 3 /Ba 0.5 Sr 0.5 TiO 3 nanoparticles have superior photocatalytic activity. The order of photocatalytic activity is as follows: WO 3 /Ba 0.5 Sr 0.5 TiO 3 > WO 3 /SrTiO 3 > WO 3 /BaTiO 3. Several organic pollutants, such as rhodamine B, methyl parathion, direct brilliant yellow-4R, and methylene blue, can be efficiently degraded using WO 3 /Ba 0.5 Sr 0.5 TiO 3 under visible light, and the RhB has higher degradation rate. After four cycles, WO 3 /titanate nanocomposites still have relatively high stability and reusability. •OH plays a major role in three WO 3 /titanates photocatalytic degradation. It is expected that the Z-scheme WO 3 /Ba 0.5 Sr 0.5 TiO 3 photocatalytic technology creates a good foreground for disposing of dyes and pesticides in water and wastewater. [ABSTRACT FROM AUTHOR]

In this study, we tested the insectistatic and insecticidal effects of the ethanolic extract of stems and bark of Ficus petiolaris Kunth (Moraceae) in laboratory bioassays with an artificial diet against newly hatched larvae of the fall armyworm, Spodoptera frugiperda Smith (Lepidoptera: Noctuidae). The extract was evaluated at five different concentrations (500, 1000, 1500, 2000, and 2500 ppm). The 2500 ppm extract had the strongest inhibitory effects on larval (89%) and pupal (20%) weight as well as the highest mortality (80%). The positive control, methyl parathion (Methyl Parathion®) at 1%, eliminated 100% of the fall armyworm, and the negative control (artificial diet) had a mortality of only 5%. Chemical fractionation of F. petiolaris stem and bark extract produced five fractions of FpR1-5, each of which was evaluated at 250, 500, 750, 1000, and 1250 ppm. FpR4 presented the strongest inhibitory effect, reducing the weight of the larva and pupa by 35% and 18%, while FpR2 had the strongest insecticidal effect, with 90% mortality at 1250 ppm. The pure 8-Methoxypsoralen compound extracted from this fraction was even more effective, with 100% S. frugiperda mortality at 100 ppm. The 50% lethal concentration (LC50) of 8-Methoxypsoralen was 67.68 ppm. Our results indicate that the F. petiolaris extract showed toxic activity against the fall armyworm, and its compound 8-Methoxypsoralen showed strong insecticidal activity at low concentrations. [ABSTRACT FROM AUTHOR]

There is still much to learn with respect to the potential for microplastics (MPs) to interact with environmental toxins and biota. In the present study, we investigated the effect of MPs on the toxicity of copper (Cu) to rice seeds (Oryza sativa L.). The 7‐day median effective concentration (EC50) value of MPs on rice seed germination was 864 mg/L (95% confidence interval [CI] 839 to 897 mg/L). We found that MPs slightly reduced Cu toxicity to rice seeds. The 7‐day EC50 of Cu on rice seed germination increased from 7.29 mg/L (95% CI 7.10–7.52 mg/L) to 7.93 mg/L (95% CI 7.58–8.08 mg/L) in the presence of 20 mg/L MPs. We examined this toxicity reduction phenomenon by investigating the role of MPs in the process of Cu transport, Cu accumulation, and metabolic responses. Further investigation found that the MPs used in the present study hardly adsorbed Cu, but these MPs accumulated on the coats of rice seeds and significantly reduced Cu accumulation in rice seedlings. When Cu concentration was 10 mg/L, the presence of MPs reduced the accumulation of Cu in rice seedlings by 34%. We also found that, compared with only Cu present, the addition of MPs resulted in lower reactive oxygen species accumulation and higher catalase activity and glutathione levels in rice seedlings, which also contributed to Cu toxicity reduction. Collectively, the present study shows that polystyrene MPs have the potential to form associations with plant structures which can ultimately impact heavy metal bioaccessibility and therefore toxicity. Environ Toxicol Chem 2024;43:1870–1879. © 2024 SETAC [ABSTRACT FROM AUTHOR]

Sensors play a critical role in the detection and monitoring of various substances present in our environment, providing us with valuable information about the world around us. Within the field of sensor development, one area that holds particular importance is the detection of small molecules. Small molecules encompass a wide range of organic or inorganic compounds with low molecular weight, typically below 900 Daltons including gases, volatile organic compounds, solvents, pesticides, drugs, biomarkers, toxins, and pollutants. The accurate and efficient detection of these small molecules has attracted significant interest from the scientific community due to its relevance in diverse fields such as environmental pollutants monitoring, medical diagnostics, industrial optimization, healthcare remedies, food safety, ecosystems, and aquatic and terrestrial life preservation. To meet the demand for precise and efficient monitoring of small molecules, this summary aims to provide an overview of recent advancements in sensing and quantification strategies for various organic small molecules including Hydrazine, Glucose, Morpholine, Ethanol amine, Nitrosamine, Oxygen, Nitro-aromatics, Phospholipids, Carbohydrates, Antibiotics, Pesticides, Drugs, Adenosine Triphosphate, Aromatic Amine, Glutathione, Hydrogen Peroxide, Acetone, Methyl Parathion, and Thiophenol. The focus is on understanding the receptor sensing mechanism, along with the electrical, optical, and electrochemical response. Additionally, the variations in UV–visible spectral properties of the ligands upon treatment with the receptor, fluorescence and absorption titration analysis for limit of detection (LOD) determination, and bioimaging analysis are discussed wherever applicable. It is anticipated that the information gathered from this literature survey will be helpful for the perusal of innovation regarding sensing strategies. [ABSTRACT FROM AUTHOR]

One of the most pressing global environmental issues is the widespread abundance and distribution of microplastics (MPs). MPs can act as vectors for other contaminants in the environment making these small plastic particles hazardous for ecosystems. The presence of MPs in aquatic environments may pose threats to aquatic organisms that ingest them. This study examined effects of abamectin (ABM) and polyethylene terephthalate (PET) MP fragments on histopathological and enzymatic biomarkers in zebrafish (Danio rerio). Zebrafish were exposed for 96 h to pristine PET-MPs at concentrations of 5 mg/L and 10 mg/L, ABM alone at 0.006 mg/L, and the same concentration of ABM in the presence of PET-MPs in aquaria. Histopathological analysis revealed tissue content changes in liver and kidney in the presence of ABM individually and in combination with MPs. Results of enzymatic analysis showed that MPs increased the bioavailability and toxicity of pesticides due to inhibition of catalase (CAT) and acid phosphatase (ACP) enzymes. However, MPs did not affect the toxicity of ABM for glutathione s-transferase (GST) enzyme. Despite the inhibition of acetylcholinesterase (AChE) in MPs or ABM treatments, and some neurotoxicity, no change in activity of this enzyme and neurotoxicity was observed in the combined MPs and ABM treatments, although toxicity effects of MPs and ABM on zebrafish require more detailed studies. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to explore the effects of the variations in biodegradable and nonbiodegradable microplastic particles (MPs) on the absorption of lead (Pb) in maize. Materials and methods: Pot experiments were conducted using maize and two types of MPs, nonbiodegradable polyethylene (PE) and biodegradable polybutylene adipate/terephthalate (PBAT), at four different MP concentrations (0, 0.1, 1, and 10%). After one month of growth, the Pb content in aboveground and belowground parts of the maize seedlings, CaCl2-extracted Pb content, the proportion of different speciation of Pb within the soil, and soil properties were determined. We determined Pb uptake by maize seedlings, soil physicochemical properties, and Pb speciation in soil. Results: The addition of PE and PBAT particles led to the decrease in Pb content in maize root with the increase in concentration. The addition of 0.1% PBAT particles significantly increased the Pb content in the shoot of maize plants by 37.60% and Pb content in the root by 65.06% compared with 0.1% PE. The addition of PE and PBAT particles increased the proportion of residual Pb to 36.0% and 38.0%, respectively. The correlation analysis showed that the addition of MPs mainly affected the absorption of Pb by maize plants by affecting soil pH, dissolved organic carbon (DOC), cation exchange capacity (CEC), free crystalline Mn (MnDCB), and amorphous Fe (FeTamm). Conclusions: This study demonstrates that biodegradable and nonbiodegradable MPs in soil inhibited Pb accumulation in maize seedling roots. FeDCB, MnDCB, and FeTamm may be the main control factors affecting the inhibition of lead uptake by PE in maize seedling roots. Additionally, FeTamm may be the main controlling factor influencing PBAT to reduce lead accumulation in maize seedling roots. The results of the present study could provide novel insights into the toxicity and bioavailability effects of MPs and Pb on maize, as well as a valuable reference for ongoing research on the ecological risk assessment of MPs and other pollutants in the soil environment. [ABSTRACT FROM AUTHOR]

A simple, one-pot method was designed for preparing nanocomposite material and its potential applications for water remediation. X-ray diffraction, Fourier Transform infrared, scanning, and transmission electron microscopy, thermogravimetric analysis and derivative thermogravimetry, and N2 adsorption and desorption isotherm techniques were used to examine the chemical and physical characteristics of the prepared nanomaterials. The developed nano-sized sorbent has a good surface area of about 106.788 m2 g−1. The synthesized nanocomposite was employed as a sorbent to remove several heavy metals, such as Cd(II), Cu(II), Fe(III), Pb(II), Mn(II), and Cr(VI), and different pesticides (e.g., Diazinon, Parathion Methyl, Malathion, Parathion ethyl, Epoxide, DDE, Dieldrin, and Aldrin). The removal efficiencies were found to be in the range of 9.52–94.8%, 23.14–99.40%, and 8.91–85.50% for pesticides, heavy metals, and physical contaminants, respectively. In addition, the sorption capacities of the different metals ranged from 2.31 to 9.94 mg g−1, and from 2.67 to 28.00 mg g−1 for different pesticides. While it was 31.49–306.63 mg g−1 for physical contaminants. [ABSTRACT FROM AUTHOR]

The rapid and efficient identification and quantification of neurotoxic organophosphorus pesticides (OPs) are crucial for ensuring environmental safety and human health. However, the current acetylcholinesterase OP sensors are largely limited by the stability and cost of bio-enzymes, as well as the occurrence of false negatives in "signal-off" strategies. In this study, we present a pioneering approach that utilizes high-performance electrochemiluminescence (ECL) of tungsten disulfide quantum dots (WS2 QDs) to develop an alternative sustainable non-enzymatic ECL sensor for "signal-on" OP detection. The presence of phosphate esters in OPs efficiently mediates ECL enhancement of WS2 QDs using K2S2O8 as a coreactant. With this new strategy, we achieved highly sensitive and selective detection of common OPs, including methyl parathion, naled, dimethoate, and malathion, with detection limits of 1.48 pg mL−1, 4.30 pg mL−1, 0.35 pg mL−1, and 5.58 pg mL−1, respectively. When applied to river water and spinach samples, the sensor also demonstrated high reproducibility and good recovery. The electrochemical hydrolysis decomposition of OPs during the detection process in this study provides a "two birds with one stone" strategy, serving the dual objective of identifying and degrading OPs. This work paves a new avenue for direct ECL sensing in environmental and food screening, eliminating the reliance on common indirect biological identification elements. [ABSTRACT FROM AUTHOR]

A new catalyst, Sm2NdSbO7, was synthesized for the first time by solid-phase sintering. The study utilized X-ray diffraction, transmission electron microscope energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to examine the structural characteristics of monocrystal BiDyO3, monocrystal Sm2NdSbO7 and Sm2NdSbO7/BiDyO3 heterojunction photocatalysts (SBHP) prepared by solid-phase sintering. The Sm2NdSbO7 photocatalyst owned a pyrochlorite structure, belonged to the face-centered cubic crystal system, possessed a space group of Fd3m and a bandgap width of 2.750 eV. After 145 min of visible light irradiation (145-VLIRD), the removal rate (RMR) of methyl parathion (MP) or total organic carbon of SBHP was 100% or 97.58%, respectively. After 145-VLIRD, the photocatalytic degradation rates of SBHP to MP were 1.13 times, 1.20 times, and 2.43 times higher than those of the Sm2NdSbO7 photocatalyst, the BiDyO3 photocatalyst, and the nitrogen-doped TiO2 catalyst, respectively. The experimental results showed that SBHP had good photocatalytic activity. After four cycles of cyclic degradation experiments with SBHP, the elimination rates of MP were 98.76%, 97.44%, 96.32%, and 95.72%, respectively. The results showed that SBHP had good stability. Finally, the possible degradation pathways and degradation mechanisms of MP were speculated. In this study, we successfully developed a high-efficiency heterojunction catalyst which responded to visible light and possessed significant photocatalytic activity. The catalyst could be used in photocatalytic reaction system for eliminating the harmful organic pollutants from wastewater. [ABSTRACT FROM AUTHOR]

In the ratiometric fluorescent (RF) strategy, the selection of fluorophores and their respective ratios helps to create visual quantitative detection of target analytes. This study presents a framework for optimizing ratiometric probes, employing both two-component and three-component RF designs. For this purpose, in a two-component ratiometric nanoprobe designed for detecting methyl parathion (MP), an organophosphate pesticide, yellow-emissive thioglycolic acid-capped CdTe quantum dots (Y-QDs) (analyte-responsive), and blue-emissive carbon dots (CDs) (internal reference) were utilized. Mathematical polynomial equations modeled the emission profiles of CDs and Y-QDs in the absence of MP, as well as the emission colors of Y-QDs in the presence of MP separately. In other two-/three-component examples, the detection of dopamine hydrochloride (DA) was investigated using an RF design based on blue-emissive carbon dots (B-CDs) (internal reference) and N-acetyl L-cysteine functionalized CdTe quantum dots with red/green emission colors (R-QDs/G-QDs) (analyte-responsive). The colors of binary/ternary mixtures in the absence and presence of MP/DA were predicted using fitted equations and additive color theory. Finally, the Euclidean distance method in the normalized CIE XYZ color space calculated the distance between predicted colors, with the maximum distance defining the real-optimal concentration of fluorophores. This strategy offers a more efficient and precise method for determining optimal probe concentrations compared to a trial-and-error approach. The model's effectiveness was confirmed through experimental validation, affirming its efficacy. [ABSTRACT FROM AUTHOR]

Low-power and smart sensing systems for iron detection are necessary for in situ monitoring of water quality. Here, a potentiometric Fe2+-selective electrode (ISE) was fabricated based on cyanomethyl N-methyl-N-phenyl dithiocarbamate for the first time as an ionophore. Under optimal conditions, the ISE showed a Nernstian slope of 29.76 ± 0.6 mV per decade for Fe2+ ions over a wide concentration range from 1.0 × 10−1 to 1.0 × 10−5 M with a lower detection limit (LOD) of 1.0 × 10−6 M. The ISE interference of various cations on the potentiometric response was also investigated. The ISE had a response time less than 3 s and the lifetime was two months. Also, an automated, long-range (LoRa), wireless enabled sampling microfluidic device powered with a solar panel as an autonomous power source was developed for a continuous sampling and sensing process. The sensing platform was employed in the determination of Fe2+ in acid mine drainage and spiked water samples with an average recovery of 100.7%. This simple, inexpensive (below $350), portable sensing platform will allow for rapid real-time monitoring of ground-, drinking-, and industrial waters contaminated with iron. [ABSTRACT FROM AUTHOR]

Introduction: A new analytical method based on the coupling of microextraction and microfluidics was developed and investigated for the pre-concentration, separation, and electrochemical detection of fenitrothion (FT) and parathion (PA) at the sub-ppm concentrations. Methods: In the first step, the microchip capillary electrophoresis technique was used to serve as a separation and detection system. Analytes were injected in the 40 mm long microchannel with 10 mm sidearms. Then, they were separated by applying a direct electrical field (+1800 V) between the buffer and detection reservoirs. 2-(n-morpholino)ethanesulfonic acid (MES) buffer (20 mM, pH 5) was used as a running buffer. The electrochemical detection was performed using three Pt microelectrodes with the width of working, counter, and reference electrodes (50, 250, and 250 µm, respectively) in the out-channel approach. Results: The system was devised to have the optimum detection potential equal to -1.2 V vs. pseudo-reference electrode. The dimensions of the SU-8 channel have 20 µm depth and 50 µm width. In the second step, an air-assisted liquid-liquid microextraction technique was used to extract and preconcentration of analytes from human blood plasma. Then, 1, 2 di-bromoethan was used as extractant solvent, the analytes were preconcentrated, and the sedimented solvent (50 µL) was evaporated in a 60 °C water bath followed by substitution of running buffer containing 10% ethanol. The optimal extraction cycles were found to be 8 with adding 1% NaCl to the aqueous phase. Analyzing time of the mentioned analytes was less than 100s, the precision range was 3.3 - 8.2 with a linear range of 0.8-100 ppm and 1.2-100 ppm for FT and PA, respectively. The extraction recoveries were about 91% and 87% for FT and PA, respectively. The detection limits for FT and PA were 240 and 360 ppb, respectively. Finally, the reliability of the method was investigated by GC-FID. Conclusion: The proposed method and device were validated and can be used as in situ and portable detection systems for detecting fenitrothion and parathion insecticides. [ABSTRACT FROM AUTHOR]

Pesticides containing chlorine, which are released during agricultural activities, are chemical substances that mix with surface and underground waters and have toxic, carcinogenic, and mutagenic effects on the entire living ecosystem. Due to their chemically stable structure, conventional water and wastewater treatment techniques such as coagulation, flocculation, and biological oxidation do not entirely remove these chemical substances. Therefore, before releasing them into the environmental receptor, these chemical substances must be transformed into harmless products or mineralized through advanced oxidation processes. When we look at the literature, there are not many studies on methods of removing diclofop methyl from aquatic media. Our study on the removal of diclofop methyl herbicide from aquatic media using the peroxy electrocoagulation method will provide the first information on this subject in the literature. In addition, this treatment method will contribute significantly to filling an important gap in the literature as an innovative approach for diclofop methyl removal. Moreover, peroxy electrocoagulation, which produces less sludge, provides treatment in a short time, and is economical, has been determined to be an advantageous process. The effects of conductivity, pH, H2O2 concentration, current, and time parameters on the removal of diclofop methyl were investigated using a GC–MS instrument. Kinetics, energy consumption, and cost calculations were also made. Under the optimum conditions determined (pH = 5, H2O2 = 500 mg/L, NaCl = 0.75 g/L, current density = 2.66 mA/cm2), the peroxydic electrocoagulation process resulted in a diclofop methyl removal efficiency of 79.2% after a 25-min reaction. When the experimental results were analyzed, it was found that the results fitted the pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]

Herein, a novel electrochemical sensor was designed for the sensitive determination of methyl parathion (MP) using the Super P Li carbon black@β-cyclodextrin (SPLCB@β-CD) decorated glassy carbon electrode (GCE). SPLCB with high electroactive area exhibited exceptional conductivity and good dispersive property, which is beneficial for forming the interlinked conductive network structure. β-CD could not only promote the uniform dispersion of SPLCB but also effectively realise the enrichment of MP molecules. Moreover, the existence of SPLCB could make up for the defect of poor conductivity of β-CD. Under the optimal experimental condition (pH = 7.0, enrichment time: 60 s). The collaborative cooperation of SPLCB and β-CD achieved the excellent MP detection property (LOD: 8.6 nM; concentration range: 0.01–10 μM). The SPLCB@β-CD/GCE sensor exhibited acceptable repeatability and reproducibility. In addition, the proposed sensor was successfully employed to detect MP in apple juice (Recoveries: 98.0–98.6%, RSD values: 3.68–4.63%). [ABSTRACT FROM AUTHOR]

Herein, an efficient and sensitive methyl parathion (MP) electrochemical sensor was fabricated by using β-cyclodextrin (β-CD) decorated single-wall carbon nanotubes (SCN), which were used to modify the glassy carbon electrode (GCE). The β-CD@SCN/GCE sensor achieved the sensitive MP detection. For the obtained β-CD@SCN nanocomposite, SCN could form three-dimensional reinforced carbon conductive network with good conductivity property and efficient charge transport channels; β-CD could promote the dispersion of carbon materials and boost the accumulation capability of MP on the surface of β-CD@SCN/GCE. The combination of β-CD and SCN significantly optimized the electrochemical property of β-CD@SCN/GCE sensor for the detection of MP. The β-CD@SCN/GCE sensor exhibited good MP electrochemical detection performance with low limit of detection of 7.23 nM. When used for the detection of MP in grape juice, the β-CD@SCN/GCE sensor exhibited good MP electrochemical sensing analysis performance with satisfactory recovery rates (96.54–98.18%) and relative standard deviation values (1.60–2.07%). [ABSTRACT FROM AUTHOR]

Reformatsky reagent obtained from methyl 1-bromocyclopentanecarboxylate and zinc selectively added to the carbon–carbon double bond of the heterocyclic fragment of 3-(3-arylacryloyl)-2H-chromen-2-ones to give the corresponding addition products after hydrolysis of the reaction mixture. According to the X-ray diffraction data, the products exist in the enol form. Despite the use of excess Reformatsky reagent, elevated temperature, and prolonged reaction time, neither addition to the acryloyl fragment nor intramolecular cycliza-tion of the addition products was observed. [ABSTRACT FROM AUTHOR]

The samples of greenhouse cucumbers were collected from the Central Fruit and Vegetable Market of Tabriz between June and December 2017. In the twenty-four cucumber samples (unwashed, washed, peeled), the residue of 18 organophosphates pesticides (OPPs) was analyzed using gas chromatography-mass spectrometry (GC-MS) following the modified QuEChERS method (quick, easy, cheap, effective, rugged and safe). Chronic non-carcinogenic risk assessment from pesticide residues in the samples was also performed for age groups of adults (women and men) and children using the Monte Carlo Simulation (MCS). Amongst the eighteen studied pesticides, eight pesticides including dimethoate, diazinon, methyl parathion, fenitrothion, chlorpyrifos, profenofos, ethion, and azinphos-methyl were detected. Pesticide residues were detected in 100% of unwashed, washed and peeled samples in the range of 0.08 to 0.37 mg.kg-1, 0.03 to 0.17 mg.kg-1 and 0.01 to 0.08 mg.kg-1, respectively. The maximum and minimum values were found for diazinon pesticides with 0.37 mg.kg-1 and profenofos and fenitrothion with 0.01 mg.kg-1. 100 % of samples contained at least three pesticide residues (dimethoate, diazinon, and methyl parathion), while 87.5% of the samples contained more pesticides residues. The residues of dimethoate, diazinon, and methyl parathion were above Maximum Residue Limits (MRL) in 100%, 83.33%, and 66.66% of samples, respectively. The identified residues were more than the EU MRLs and the IR MRLs in 100% and 95.83% samples, respectively. The mean reduction of pesticide residues in the washed and peeled samples was in the range of 37.74 to 56.52% and 66.66 to 92.30%, respectively. According to the performed risk assessment, there is no significant non-carcinogenic health risk due to the consumption of cucumber for the age group of adults. Hence, there is a considerable non-carcinogenic health risk to children due to the consumption of unwashed (HI = 2.22) and water-washed (HI = 1.36) greenhouse cucumbers. [ABSTRACT FROM AUTHOR]

Objective: In order to achieve rapid detection of methyl parathion. Methods: An acetylcholinesterase sensor was prepared based on gold nanoparticles and reduced graphene oxide for quantitative detection of Methyl parathion. Reduced graphene oxide, gold nanoparticles and acetylcholinesterase were successively modified on the surface of the screen printing electrode by layer-by-layer assembly method. The catalytic activity and impedance characteristics of the sensor, the relationship between the sensor's inhibition rate and MP concentration, and the actual sample detection were evaluated. Results: The prepared acetylcholinesterase biosensors showed excellent affinity for acetylthiocholine chloride with the Michaelis-Menten constant of 2.76 mmol/L. Under the optimal conditions, Methylparathion could be effectively detected with a linear range of 5 ng/mL to 500 ng/mL and a detection limit of 0.692 ng/mL. Conclusion: The method is simple, practical and stable. It provides a reliable method for rapid detection of organophosphorus pesticides.

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. [ABSTRACT FROM AUTHOR]

Organophosphorous (OP) pesticides can cause many human diseases. In this study, the separation and determination of two organophosphorous pesticides (diazinon and methyl-parathion) in biological samples using solid-phase extraction method prior to their measurements by high‐performance liquid chromatography (HPLC) were investigated. Herein, a new functionalized cerium-based metal–organic framework (MOF) bearing oxime moiety, denoted here UiO-66(Ce)-MO, was synthesized through two-synthetic steps from the pristine UiO-66(Ce) and then applied as an efficient porous adsorbent for the extraction of pesticides from biological samples. Various techniques including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET) analysis were used for the description of adsorbent. The optimization of variables was performed by Box–Behnken design combined with response surface methodology. The factors' effects including pH, eluent volume (EV), sample flow rate (SF) and eluent flow rate (EF) were also examined. The optimum conditions for both compounds were pH 5.5, eluent volume 0.6 mL, SF 2 mL min−1, and EF 0.2 mL min−1, leading to 97.1% and 96.0% removal of diazinon and methyl-parathion, respectively. Under the optimum conditions, the maximum adsorption capacity was obtained 454.5 mg g−1 for methyl-parathion and 476.2 mg g−1 for diazinon. The limit of detection (LOD) was found to be 0.04 μgL−1 for diazinon and 0.06 μgL−1 for methyl-parathion. Sensitivity analysis showed that pH plays a significant role on the efficiency of both organic pollutants. Remarkably, the results showed that this adsorbent outperforms the other UiO-66(Ce) samples and is suitable for separation and determination of these organic materials from water and biological real samples (blood plasma and urine). A porous oxime-functionalized Ce-MOF, UiO-66(Ce)-MO, was synthesized and applied for efficient extraction and determination of trace amounts of methyl-parathion and diazinon from water and biological samples. [ABSTRACT FROM AUTHOR]

It is of great significance to develop an effective method for methyl parathion (MP) detection. Herein, a novel nitrogen‐doped titanium carbide quantum dots (N‐Ti3C2 QDs) was prepared and used to construct a simple and sensitive fluorescence sensing platform of MP by making use of inner filter effect (IFE). The prepared N‐Ti3C2 QDs can exhibit strong blue fluorescence at 434 nm. Meanwhile, MP could hydrolyze to produce p‐nitrophenol (p‐NP) under alkaline conditions, which showed a characteristic ultraviolet‐visible (UV‐visible) absorption peak at 405 nm, resulting in the fluorescence of N‐Ti3C2 QDs is effectively quenched by p‐NP. In addition, the investigation of time‐resolved fluorescence decays indicated that the corresponding quenching mechanism of p‐NP on N‐Ti3C2 QDs is due to the IFE. After optimizing the conditions, the as‐developed fluorescence sensing platform displayed wide detection range (0.1–30 μg mL−1) and low detection limit (0.036 μg mL−1) for MP, and it was also successfully applied for MP analysis in real water samples, thus it is expected that this simple, sensitive and enzyme‐free sensing platform shows great applications. [ABSTRACT FROM AUTHOR]

The hydrochloric acid (HCl 0.1 M) supporting electrolyte was used in the electrochemical estimation cyclic voltammetry for CaCl2 concentrations also using crystal violet dye or (hexamethyl pararosaniline) as ligand. For oxidation and reduction waves, the potential range is 0.5 V, -0.5 V. The interaction of calcium ions with crystal violet was examined using several analytical estimates, and kinetic and thermodynamic parameters. The analytical concentration for calcium ions in different samples especially in Nile River were estimated in the range from 1.6 to 14.3 mmol. The estimation of calcium ion concentrations was achieved up to 11.49 mmol in waste water in Mansoura University. Applications were made for calcium estimation of different water samples and molecular docking of the calcium-crystal violet complex against the Hepatitis C viral proteins (4i33, 4KTC), roving strong bonds of interaction were observed. And anti-bacterial effect on calcium complex with crystal violet and face mask N-95 tissue. [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.)

An unprecedented photocatalyst, Sm2EuSbO7, was successfully fabricated in this paper, through a high-temperature solid-state calcination method, which represented its first ever synthesis. Additionally, using the solvothermal method, the Sm2EuSbO7/ZnBiSbO5 heterojunction photocatalyst (SZHP) was fabricated, marking its debut in this study. XRD analysis confirmed that both Sm2EuSbO7 and ZnBiSbO5 exhibited pyrochlore-type crystal structures with a cubic lattice, belonging to the Fd3m space group. The crystal cell parameter was determined to be 10.5682 Å or 10.2943 Å for Sm2EuSbO7 or ZnBiSbO5, respectively. The band gap width measured for Sm2EuSbO7 or ZnBiSbO5 was 2.73 eV or 2.61 eV, respectively. Under visible light irradiation for 150 min (VLTI-150 min), SZHP exhibited remarkable photocatalytic activity, achieving 100% removal of parathion methyl (PM) concentration and 99.45% removal of total organic carbon (TOC) concentration. The kinetic constant (k) for PM degradation and visible light illumination treatment was determined to be 0.0206 min−1, with a similar constant k of 0.0202 min−1 observed for TOC degradation. Remarkably, SZHP exhibited superior PM removal rates compared with Sm2EuSbO7, ZnBiSbO5, or N-doped TiO2 photocatalyst, accompanied by removal rates 1.09 times, 1.20 times, or 2.38 times higher, respectively. Furthermore, the study investigated the oxidizing capability of free radicals through the use of trapping agents. The results showed that hydroxyl radicals had the strongest oxidative capability, followed by superoxide anions and holes. These findings provide a solid scientific foundation for future research and development of efficient heterojunction compound catalysts. [ABSTRACT FROM AUTHOR]

Summary: The effect of complex organic acids (COA) treatment at different concentrations (0%, 1%, 5%, 10% and 15%) on the myofibrillar protein (MP) structure and meat quality of crayfish (Procambarus clarkii) was investigated. The results showed that with increasing concentrations of COA treatment, the sulfhydryl content of MP decreased and dityrosine content increased. The MP secondary structure has a reduced α‐helix content and an increased β‐fold content. The MP tertiary structure unfolded, exposing hydrophobic and other amino acids to a polar environment. MP aggregation was induced in the 1% and 5% COA treatment groups and MP degradation was induced in the 10% and 15% COA treatment groups. Crayfish meat in the 5% COA treatment group showed improved textural properties due to protein aggregation. It also enhanced the colour, aroma and micromorphology of the crayfish meat. [ABSTRACT FROM AUTHOR]

Methyl parathion (MP), an organophosphorus insecticide, is commonly used in agricultural products for food preservation and pest control. Due to the severe threat it poses to food safety and the environment, monitoring MP residues has attracted much attention. Traditional spectroscopic and chromatographic methods have been used successfully to analyze MP in a wide range of samples; however, these approaches have several drawbacks, such as requiring specialized equipment, trained technicians, and extensive sample preparation time. Due to these restrictions, there is a growing demand for analysis methods that can reliably and quickly detect MP at trace quantities while also being quick, sensitive, and selective. Electrochemical sensors have emerged over the past few decades as a viable alternative to more time-consuming and laborious analysis methods for detecting MP. However, the performance of electrochemical sensors has been dramatically improved thanks to recent breakthroughs in nanoscience. This study offers an overview of the creation and operation of carbon nanomaterial-based electrochemical sensors (including carbon nanotubes (CNTs), graphene (Gr), and other carbon nanomaterials) to identify MP residues in waters, fruits, and vegetables. A brief discussion of the potential benefits, drawbacks, and future research prospects of MP electrochemical sensors based on carbon nanomaterials is also offered. [ABSTRACT FROM AUTHOR]

In this work, we proposed a template-free synthesis strategy for the preparation of morning glory-like porous carbon nanosheets (MGPCS) with three-dimensional (3D) interconnected porous carbon structure, which was applied to modify the glassy carbon electrode (GCE) for the fabrication of methyl parathion (MP) electrochemical sensor (MGPCS/GCE). MGPCS was successfully prepared by a template-free synthesis strategy with sodium citrate as carbon source. Benefitting from the high-temperature thermal decomposition and acid treatment process, the sodium citrate-derived MGPCS sample presented 3D interconnected morning glory-like porous carbon structure with good electrical conductivity, which provided more efficient charge transfer channels. In particular, the morning glory-like surface morphology significantly increased the specific surface area and adsorption capacity of sensing electrode. Under the optimal conditions, the fabricated MGPCS/GCE sensor showed highly sensitive MP detection property with low limit of detection of 10.7 nM (Linear MP concentration: 0.1–15 µM). Moreover, the fabricated sensor presented good reproducibility, repeatability, stability, and selectivity. The good practical performance of the MGPCS/GCE sensor was confirmed by detecting the MP amount in apple juice and peach juice samples. [ABSTRACT FROM AUTHOR]

The extensive use of methyl tert-butyl ether as a gasoline additive has produced environmental pollution globally due to its high solubility and recalcitrance. Due to the persistent pollution and potential toxicity, the development of technology for methyl tert-butyl ether removal has become a priority. Single technologies have limitations that can be addressed through the combination of various processes. Here, we provide a comprehensive overview of the mechanism and application of adsorption and oxidation combined process to remove methyl tert-butyl ether. The materials commonly used in combined process, such as zeolite and activated carbon, are compared. The physical and chemical properties and functions of different materials are explored. Moreover, the pretreatment mechanism and the effects of acid reagents are discussed. Furthermore, various conditions affecting the removal efficiency, such as temperature, pH, coexisting anions, are analyzed. Ultimately, the integration of adsorption and oxidation processes is promising for efficient degradation of methyl tert-butyl ether. [ABSTRACT FROM AUTHOR]

Modification of the adsorbent surfaces has been considered a fascinating strategy that enhances biomass-based adsorption properties for efficient removal of organic pollutants. This is based on the attempt to replace the cost-ineffectiveness of the commercial activated carbon. The present study discusses different modification strategies and a review on modified biomass materials for the sorption of organic contaminants. Unlike previous literatures in the field, wider range of these pollutants are discussed in this study under different categories including pesticides (such as insecticides, herbicides, fungicides), pharmaceutical (e.g. analgesic and antipyretic drugs, antibiotic drugs, non-steroidal anti-inflammatory drugs and antimalaria drugs), and dyes (e.g. azo, xanthene, miscellaneous diagnostic, tri-aryl methane, and phenol-derived polymeric dyes). It was observed that the acid-activated Posidonia oceanica and HNO3-modified rice husk displayed the highest and lowest adsorption capacities of 2681.9 and 0.35 mg/g for removing Rhodamine B dye and methyl parathion pesticide, respectively. The mechanistic aspects of organic pollutants adsorption, their corresponding regeneration studies, and environmental challenges with chemical modifications are also discussed. The use of computational (optimization) models for modified biomass-based adsorbents to remove organic pollutants is devoid in previous reviews but discussed in the present study. To foster more advancement in this field, the concluding part presents various challenges and knowledge gaps for furthering research towards more realistic industrial implementations. [ABSTRACT FROM AUTHOR]

Pesticides are chemicals used to control a wide variety of animals and plants. Methyl parathion (MP) is an organic phosphorus insecticide used in agriculture against animal organisms that damage the crop. Pesticides can reach water resources in different ways. May affect non-target organisms such as fish to varying degrees. Since fish is a valuable nutrient in human nutrition, its sustainability is very important. For this reason, sublethal effects of MP on Alburnus tarichi, which is economically important for the Lake Van basin, were studied. This study was carried out to determine the pathological effects of MP on the gonad, gill and liver tissues of Alburnus tarichi. Fish weighing 3‒7 g were used in the study. The semistatic test method was applied. Fish were exposed to 4.28 mg L-1 MP. The bioassay was carried out at 17.9 °C for 30 days. At the end of the test, gonad, gill and liver tissues were removed from the dissected fish for pathological evaluations. In the examinations made, cells with eosinophilic and fat accumulation in the liver, local necrosis and enlarged vessels, and yellow colored structures were determined. Thickened primary lamella, folded secondary lamella and epithelial layer separations were observed in the gills. No pathology was found in ovarian cells. Degeneration in the germ cells in the mitotic phase, interstitial tissue containing eosinophilic cell groups, enlarged follicle lumen and bleeding were observed in the testes that were not in the mitotic phase. As a result, MP is a chronic toxic substance according to histological criteria for Alburnus tarichi. MP should be used in agriculture in a controlled and careful way. [ABSTRACT FROM AUTHOR]

Highly sensitive and uniform three‐dimensional (3D) hybrid heterogeneous structures for use in surface‐enhanced Raman scattering (SERS) experiments were fabricated by sequentially decorating high‐quality, ultra‐clean, graphene quantum dots (GQDs) and Ag nanoparticles (Ag‐NPs) onto 3D‐graphene. Finite‐difference time‐domain calculations and scanning Kelvin probe microscopy were used to verify that the Ag‐NPs/GQDs/3D‐graphene system facilitates substantial electromagnetic enhancement (due to the occurrence of two kinds of "gaps" between the Ag‐NPs that form 3D "hot spots") and additional chemical enhancement (in detecting some π‐conjugated molecules). The SERS mechanism was explored in further detail via experimental analysis and confirmed by performing theoretical calculations. The large surface area of the 3D substrate (due to the large specific surface areas of the GQDs and 3D‐graphene) results in a better enrichment effect which helps produce lower detection limits. In particular, the detection limits obtained using the Ag‐NPs/GQDs/3D‐graphene platform can reach 10−11 M for rhodamine 6G, 10−10 M for methylene blue and dopamine, and 10−7 M for tetramethylthiuram disulfide and methyl parathion in apple juice (these are superior to most of the results reported using graphene‐based SERS substrates). In summary, the 3D‐platform Ag‐NPs/GQDs/3D‐graphene/Si shows outstanding SERS performance. It therefore has excellent application prospects in biochemical molecular detection and food safety monitoring. [ABSTRACT FROM AUTHOR]

The recovery of organophosphate pesticides (OPPs) from aqueous solutions is imperative considering their agricultural and environmental implications. Among various mitigation approaches used for OPPs' removal, adsorption offers many advantageous features for OPPs abatement owing to its benign nature, cost-effective processing, and non-requirement of excessive equipment. This research describes the adsorptive removal of three organophosphate pesticides (OPPs) namely chlorpyrifos (CPF), methyl parathion (MP), and malathion (MAL) by HKUST–1 (HKUST = Hong Kong University of Science and Technology) metal–organic framework (MOF). The synthesis of HKUST–1 MOFs was confirmed by various spectroscopic and microscopic techniques. The adsorption kinetics was systematically investigated by varying three parameters to include solution pH, contact time, and initial pesticide concentration. Among all the three pesticides, HKUST–1 showed enhanced removal of CPF in terms of pH, resulting in an adsorption capacity of 1.82 mg·g−1. However, under the effect of contact time at 60 min, the adsorption capacity of HKUST-1 for PM, MAL, and CPF were computed to be 1.83, 1.79, and 0.44 mg·g−1, respectively. Besides, HKUST–1 showed a remarkable performance towards adsorptive removal of MAL (14.01 mg·g−1 at 10 mg·L−1 concentration) with linear increase in adsorption capacity as the function of initial pesticide concentration. The MOFs were also able to retain ca. 50% of their adsorption efficiency over the course of five cycles of adsorptive removal of CP. In the future, a comprehensive data table showing the performance of various MOFs against various OPPs can be constructed on the basis of parameters used in this study. [ABSTRACT FROM AUTHOR]

In this contribution, we describe the kinetics associated with the rac-Me2Si[2-Me-4-Ph-Ind]2ZrCl2 (Cat-1)/borate/TIBA catalyzed copolymerization of E/dienes (isoprene (IP), butadiene (BD), 5-ethylidene-2-norbornene (ENB), 4-vinylcyclohexene (VCH) and vinyl norbornene (VNB)), and E/diene/1-hexene (1H) terpolymerization by using thiophenecarbonyl chloride (TPCC) that was used in Ziegler-Natta (Z-N) and metallocene-catalyzed polyethylene (PE) and polypropylene (PP) and E/P polymerizations. In both types of polymerizations, a higher amount of dienes was incorporated when VNB (2.70 mole %) and VCH (1.56 mole %) were added as comonomer, but IP and BD were incorporated with the moderated rate (0.6-1.1 mole %) with higher activities (3.45x106gm/mmolMt·h). The active center [Zr]/[C*] fraction is higher (61%) than previously reported PE polymerizations, especially in the case of E/IP, E/BD and E/IP/1H but lower than E/P (87%) copolymerization. Significantly, IP and BD activated the inactive catalytic sites that were dormant in the PE. The propagation rate constant (kpE) with IP was higher (kp564 Lmol-1s-1), while kpE with VNB (kp379 Lmol-1s-1) and VCH (kp304 Lmol-1s-1), which were lower than PE. This difference is built because of the diffusion barrier in the system. Compared to E/diene copolymers, kpE values in E/diene/1H terpolymerizations for IP, VCH, and VNB are higher and stable except ENB and determine that 1H prevents the insertion of dienes and reduces the crystalline properties resultant moderate kpE. Even though the E/BD copolymers decreased butadiene content of over 2 mol% resulted in better crystalline characteristics, lower diffusion barriers, and a higher kpE value. In concept, IP and BD are linear and readily available for coordination. While VCH, ENB and VNB are cyclic and bulky, metallocene in contact ion pairs cannot accept ENB, VNB, and VCH for coordination and subsequently act as dormant in the polymerization. [ABSTRACT FROM AUTHOR]

In this study, a colorimetric sensor was developed for the detection of organophosphorus pesticides (OPs) using a heterogeneous nanozyme with phosphatase-like activity. Herein, this heterogeneous nanozyme (Au-pCeO2) was obtained by the modification of gold nanoparticles on porous cerium oxide nanorods, resulting in synergistic hydrolysis performance for OPs. Taking methyl parathion (MP) as the target pesticide, the catalytic performance and mechanism of Au-pCeO2 were investigated. Based on the phosphatase-like Au-pCeO2, a dual-mode colorimetric sensor for MP was put forward by the analysis of the hydrolysis product via a UV-visible spectrophotometer and a smartphone. Under optimum conditions, this dual-mode strategy can be used for the on-site analysis of MP with concentrations of 5 to 200 μM. Additionally, it can be applied for MP detection in pear and lettuce samples with recoveries ranging from 85.27% to 115.87% and relative standard deviations (RSDs) not exceeding 6.20%, which can provide a simple and convenient method for OP detection in agricultural products. [ABSTRACT FROM AUTHOR]

The study is aimed to investigate the influence of nano-Fe2O3 (NF) on various properties of cement mortar with marble powder (MP) as supplementary cementing material (SCM). The MP and NF were incorporated by partial replacement and weight of cement, respectively. The fresh and hardened properties of each mix were examined. The microstructure of hydrated blended cement mortars was evaluated by scanning electron microscopy and X-ray energy-dispersive techniques. The durability properties were assessed by water absorption and rapid chloride penetration test. The addition of an optimum amount of MP and NF in combination or individually enhanced the mechanical properties compared to control specimens (MP + NF > NF > MP > Control). However, exceeding the ideal concentration led the nanoparticles to cluster, which decreased the mechanical characteristics by increasing porosity. Our findings support the use of MP and NF in concrete technology to be used as SCMs to enhance the properties of concrete structures. [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.)

Pesticides are extremely hazardous to human health as well as various kinds of non-target organisms. The honey bee (Apis mellifera) is not only a dominant pollinator, but also a good indicator of pesticide residue and pollutants in the environment. At the time of sample collection in each village, the surrounding flora was Triticum aestivum and Brassica species. The area chosen for this study covered only 15% of the land in the state of Punjab, but pesticide consumption was approximately 75% of the state consumption. Pesticides in the collected samples (from six districts) were analyzed using RP-HPLC chromatography. The chemical methoxychlor (MC) was not found in any of the six villages' honey samples; however, spiromesifen (n = 5) and aldicarb (n = 5) were the most prevalent chemicals and were found in every honey sample. The pesticides carbendazim (n = 1) and parathion methyl (n = 1) were found only in Behman (longitude 29.9224° N and latitude 75.1137° E), and Malumazra (longitude 30.2468° N and latitude 75.8500° E). The carbofuran (n = 3) was discovered in Talwandi Sabo (longitude 29.984° N and latitude 75.8500° E), Himmatpura (longitude 30.5289° N and latitude 75.3616° E), and Malumazra, while atrazine (n = 4) was discovered in all except Malumazra. Three identical pesticides were observed in Chukrian (longitude 29.9759° N and latitude 75.4476° E) and Singo (longitude 29.9092° N and latitude 75.1589° E) indicating the same pesticides used in these villages. The given study gives a summary model to use A. mellifera as a quick monitoring bioindicator of the environment. This model helps to maintain a pesticide or pollutant database of selected areas for regular monitoring of the surrounding environment. [ABSTRACT FROM AUTHOR]

Electrochemical impedance spectroscopy (EIS) is a highly effective technique for studying the surface of electrodes in great detail. EIS-based electrochemical sensors have been widely reported, which measure the charge transfer resistance (Rct) of redox probes on electrode surfaces to monitor the binding of target molecules. One of the protective drugs against hemorrhagic cystitis caused by oxazaphosphorine chemotherapy drugs such as ifosfamide, cyclophosphamide and trophosphamide is Mesna (sodium salt of 2-mercaptoethanesulfonate). The increase in the use of Mesna due to the high consumption of anti-cancer drugs, the determination of this drug in biological samples is of particular importance. So far, no electrochemical method has been reported to measure Mesna. In this research, a novel impedimetric sensor based on a glassy carbon electrode (GCE) modified with oxidized multiwalled carbon nanotubes (MWCNTs)/gold nanoparticle (AuNPs) (denoted as Au NPs/MWCNTs/GCE) for impedimetric determination of Mesna anticancer drug was developed. The modified electrode materials were characterized by field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and EIS. The electrochemical behavior of Mesna at the surface of Au NPs/MWCNTs/GCE was studied by an impedimetric method. The detection mechanism of Mesna using the proposed impedimetric sensor relied on the increase in the Rct value of [Fe (CN)6]3−/4− as an electrochemical probe in the presence of Mesna compared to the absence of Mesna as the analyte. Under the optimum condition, which covered two linear dynamic ranges from 0.06 nmol L−1 to 1.0 nmol L−1 and 1.0 nmol L−1 to 130.0 µmol L−1, respectively. The detection limit was 0.02 nmol L−1. Finally, the performance of the proposed sensor was investigated for Mesna electrochemical detection in biological samples. [ABSTRACT FROM AUTHOR]

Metal–organic framework (UiO-66) derived nanoporous carbon/electrochemically reduced graphene oxide nanocomposite (UiO-66/NPC/ERGO) was developed to fabricate an electrochemical sensor for achieving efficient detection of methyl parathion (MP) residues in food. The carbonization derivative UiO-66/NPC was synthesized by one-step pyrolysis with only UiO-66 precursor. Based on the synergistic effect of enough active absorption sites and specific absorption of UiO-66/NPC for MP as well as the high conductivity of ERGO, the UiO-66/NPC/ERGO sensor exhibited excellent sensing performance. Under the optimal conditions, a linear determination range of 20–4000 ng/mL and low limit of detection (LOD) of 0.395 ng/mL for MP was obtained by direct electrochemical oxidation using SWV. Additionally, the sensor provided excellent stability and selectivity, as well as effective determination of real samples with satisfactory recoveries (98.5–104.0%), manifesting that the UiO-66/NPC/ERGO has great potential for organophosphorus pesticide detection. [ABSTRACT FROM AUTHOR]

Background: The issue of organophosphorus (OP) poisoning remains a significant global health concern, especially prevalent in developing nations. Aims and Objective: This current investigation endeavors to examine the clinic-demographic characteristics observed among patients exhibiting symptoms of OP poisoning. Methodology: A retrospective and prospective study spanning a duration of one and half year was carried out on patients with OP poisoning at a tertiary-level medical college. Results: Throughout the study duration, a total of 40 patients presented themselves. Instances of intentional self-poisoning (95%) outweighed those of accidental exposure (5%). The preponderance of patients were identified as housewives (32.5%), succeeded by individuals in occupations such as private job, farmers, studentship, sweepers and some were unemployed (5%). Among the toxins ingested by patients, Dichlorvas (42.5%) emerged as the predominant choice (35.74%), trailed by Chlorpyrifos, Dimethoate, Methyl parathion, Phorate, Thiomate and Monocrotophos. Manifestations of nausea and vomiting, observed in 85.02% of cases, while the predominant sign was miosis, noted in 91.94%. The mean duration of hospital stays varied among the different severity level. In terms of outcomes, 75% of patients survived without the need for mechanical ventilation and the mortality rate documented in our study stood at 10%. Conclusion: The current investigation revealed that a significant proportion of the patient cohort consisted of individuals in their youthful years, with males surpassing females in representation. Deliberate poisoning incidents exceeded accidental ones. [ABSTRACT FROM AUTHOR]

In recent years, Microplastics (MPs) have gained significant attention all over the world due to their propensity to pollute the environment and transfer toxins into the food chain, thereby endangering human health. Landfill leachate seems to be an obvious source of MPs and has the capacity to contaminate surface water, groundwater and soil. MP pollution in aquatic ecosystems has received significant research attention, whereas MP pollution in terrestrial ecosystems has received less focus. The main objective of this research is to presents the current level of knowledge about the origin, detection, occurrence, and effects of MPs in Indian landfill leachate. MP concentrations in landfill leachate was ranged between 9 and 21 items/L. The most common MP shape was fiber (83%), followed by fragment (11%), film (3%), and foam (2%). The MP colour found in leachate was yellow (35%), transparent (16%), purple (15%), blue (11%), pink (8%), white (6%), black (3%), green (2%), and orange (1%). From the chemical analysis the predominant polymers detected were LDPE, PP, PET, CA, and Nitrile. This study provides information on the properties and quantity of MPs in landfill leachate, launching additional investigation into the mechanisms through which MP s reach the environment. [ABSTRACT FROM AUTHOR]

Parabens are used as preservatives in sanitizers and cosmetic products causing environmental concern, because presented potential as endocrine disrupters. Among these compounds, the most used are methylparaben and propylparaben. Thus, a study was proposed to evaluate the interaction between different concentrations (mmol L-1) of the variables methylparaben [MP] and propylparaben [PP], against the acute toxicity of the microcrustacean Artemia salina (A. salina) and Allium cepa (A. cepa) applying the 2² factorial design with an added center point. Responses were used: percent A. salina mortality (% mortality), A. cepa root growth inhibition (% root inhibition) and mitotic index (%MI). For A. salina, after 72 hours of exposure with the combination of concentration ([MP] and [PP] = 0.8 mmol L-1) caused an 80% mortality. While, A. cepa a high cytotoxicity was observed with the mixture of Parabens, exhibiting 72.3% root growth inhibition at [MP] = 1.2 mmol L-1 with [PP] = 1.2 mmol L-1. In contrast, for response %MI at [MP] = 0.3 mmol L-1 with [PP] = 0.3 mmol L-1, 2.5 %MI with 36% inhibition. In this context, parabens demonstrated high toxicity for A. salina and cytotoxicity for A. cepa, based on the interaction with the effect of the concentrations. [ABSTRACT FROM AUTHOR]

Parathion methyl is a widely used organophosphorus pesticide (OPs). OPs in agroecosystems cause severe health and environmental effects. In this study, the Pilobolus inoculum's ability to remove parathion methyl in microsystems corn crop was evaluated at the laboratory level. Agricultural soils containing Pilobolus inoculum were exposed to 50 µg/dm3 of parathion methyl. The results showed that Pilobolus inoculum can eliminate parathion methyl in 80% of microsystems, and positively influences 20% of the physiological processes of corn plants. This research into the field of myco-remediation widens the use of little-studied fungal species such as Pilobolus to remove pesticides. [ABSTRACT FROM AUTHOR]

The threat of microplastics (MPs) in aquatic systems is almost a new challenge in environmental management. The municipal wastewater treatment plants (WWTPs) act both as collectors of MPs from anthropic use and as a source to natural environments. This study is aimed to determine the abundance, characteristics, and removal of MPs in a municipal WWTP with conventional activated sludge process. Particle size/type, influent loads, and removal rate of MPs in bar screen, grit chamber, primary sedimentation, returned activated sludge, and secondary clarification units of this WWTP were studied by collecting composite samples from wastewater and sludge over a 3-month sampling campaign. Suspected MP particles were counted by light microscopy and characterized using SEM, EDS, FTIR, and TGA–DSC techniques. The mean total MPs, fibers, and fragment concentration after the grit chamber were 6608, 3594, and 3014 which were reduced to 1855, 802, and 1053 particles/L in the effluent, respectively. The sludge retention of total MPs, fibers, and fragments were 8001, 3277, and 4719 particles/L, respectively. The overall efficiency of WWTP with an activated sludge process to remove MPs was 64% and it removed 66.6% and 60% of fibers and fragments, respectively. Fibers were the dominant shape for the collected samples after the grit chamber and fragments were prevalent in the effluent. Polyethylene polymer was detected in most wastewater samples. Existing treatment processes are effective in the removal of MP particles but still act as a potential source to the aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Omnipresent microplastics (MPs) in marine ecosystems are ingested at all trophic levels and may be a vector for the transfer of persistent organic pollutants (POPs) through the food web. We fed rotifers polyethylene MPs (1–4 µm) spiked with seven congeners of polychlorinated biphenyls (PCBs) and two congeners of polybrominated diphenyl ethers (PBDEs). In turn, these rotifers were fed to cod larvae from 2–30 days post-hatching (dph), while the control groups were fed rotifers without MPs. After 30 dph, all the groups were fed the same feed without MPs. Whole-body larvae were sampled at 30 and 60 dph, and four months later the skin of 10 g juveniles was sampled. The PCBs and PBDEs concentrations were significantly higher in MP larvae compared to the control larvae at 30 dph, but the significance dissipated at 60 dph. Expression of stress-related genes in cod larvae at 30 and 60 dph showed inconclusive minor random effects. The skin of MP juveniles showed disrupted epithelial integrity, fewer club cells and downregulation of a suite of genes involved in immunity, metabolism and the development of skin. Our study showed that POPs were transferred through the food web and accumulated in the larvae, but that the level of pollutants decreased once the exposure was ceased, possibly related to growth dilution. Considering the transcriptomic and histological findings, POPs spiked to MPs and/or MPs themselves may have long-term effects in the skin barrier defense system, immune response and epithelium integrity, which may potentially reduce the robustness and overall fitness of the fish. [ABSTRACT FROM AUTHOR]