Human erythrocytes are affected by the organochloride insecticide chlordane

Emerging technologies for the removal of pesticides from contaminated soils and their reuse in agriculture

Pesticides are becoming more prevalent in agriculture to protect crops and increase crop yields. However, nearly all pesticides used for this purpose reach non-target crops and remain as residues for extended periods. Contamination of soil by widespread pesticide use, as well as its toxicity to humans and other living organisms, is a global concern. This has prompted us to find solutions and develop alternative remediation technologies for sustainable management. This article reviews recent technological developments for remediating pesticides from contaminated soil, focusing on the following major points: (1) The application of various pesticide types and their properties, the sources of pesticides related to soil pollution, their transport and distribution, their fate, the impact on soil and human health, and the extrinsic and intrinsic factors that affect the remediation process are the main points of focus. (2) Sustainable pesticide degradation mechanisms and various emerging nano- and bioelectrochemical soil remediation technologies. (3) The feasible and long-term sustainable research and development approaches that are required for on-site pesticide removal from soils, as well as prospects for applying them directly in agricultural fields. In this critical analysis, we found that bioremediation technology has the potential for up to 90% pesticide removal from the soil. The complete removal of pesticides through a single biological treatment approach is still a challenging task; however, the combination of electrochemical oxidation and bioelectrochemical system approaches can achieve the complete removal of pesticides from soil. Further research is required to remove pesticides directly from soils in agricultural fields on a large-scale.

Hyperglycemia enhances the generation of ROS and RNS that impair antioxidant power and cause oxidative damage in human erythrocytes

Hyperglycemia is a state in which excess glucose circulates in blood. Erythrocytes are in direct contact with this high glucose concentration and are greatly affected by it. We have examined the effect of hyperglycemic condition on isolated human erythrocytes under in vitro conditions. Erythrocytes were incubated with different concentrations of glucose (5, 15, 30, 45 mmol/L) for 24 h, and several biochemical parameters were determined. Treatment with high glucose concentrations increased heme degradation and methemoglobin level, while methemoglobin reductase activity was decreased. A significant increase in protein oxidation and lipid hydroperoxides with a decrease in total sulfhydryl content was seen. This suggested the generation of oxidative stress, which was confirmed by an enhanced production of reactive oxygen and nitrogen species. Hyperglycemia led to a significant decline in the antioxidant power of erythrocytes, lowering their ability to quench free radicals and reduce metal ions to lower oxidation states. The plasma membrane redox system was upregulated, while ascorbate free radical reductase activity was lowered. Glucose exposure inhibited the enzymes of glycolysis and hexose monophosphate shunt. Electron microscopy showed morphological changes resulting in the formation of echinocytes. Thus, the hyperglycemic condition generates reactive species that oxidize proteins, hemoglobin, and lipids; impair the total antioxidant capacity; and alter morphology in human erythrocytes.

Cadmium chloride generates cytotoxic reactive species that cause oxidative damage and morphological changes in human erythrocytes

Cadmium chloride (CdCl₂₎ is a widely used industrial compound that exhibits multiple organ toxicity. Cadmium is transported through blood where erythrocytes are exposed to its action. Here the effect of CdCl₂ on human erythrocytes was examined under in vitro conditions. Human erythrocytes were treated with 0.01-0.5 mM CdCl₂ for 24 h at 37 °C. Lysates were made from CdCl₂ treated and untreated (control) cells and used for further analysis. CdCl₂ treatment resulted in marked hemolysis of erythrocytes and oxidation of hemoglobin to methemoglobin. This will result in anemia and also reduce the oxygen carrying ability of erythrocytes. Hemoglobin oxidation was accompanied by degradation of heme and release of free ferrous iron moiety. Further analysis showed elevated lipid hydroperoxides and formation of advanced oxidation protein products along with reduction in total sulfhydryl content, indicating the generation of oxidative stress condition in the cell. Incubation of erythrocytes with CdCl₂ enhanced generation of reactive oxygen and nitrogen species, decreased the antioxidant power and inhibited pathways of glucose metabolism. Plasma membrane was damaged as indicated by enhanced osmotic fragility and inhibition of membrane bound enzymes. This was confirmed by electron microscopy which showed formation of echinocytes. These results show that CdCl₂ generates reactive species which impair the antioxidant system resulting in oxidative damage to erythrocytes.

Fate of Residual Pesticides in Fruit and Vegetable Waste (FVW) Processing

Plants need to be protected against pests and diseases, so as to assure an adequate production, and therefore to contribute to food security. However, some of the used pesticides are harmful compounds, and thus the right balance between the need to increase food production with the need to ensure the safety of people, food and the environment must be struck. In particular, when dealing with fruit and vegetable wastes, their content in agrochemicals should be monitored, especially in peel and skins, and eventually minimized before or during further processing to separate or concentrate bioactive compounds from it. The general objective of this review is to investigate initial levels of pesticide residues and their potential reduction through further processing for some of the most contaminated fruit and vegetable wastes. Focus will be placed on extraction and drying processes being amid the main processing steps used in the recuperation of bioactive compounds from fruit and vegetable wastes.

Bioallethrin-induced generation of reactive species and oxidative damage in isolated human erythrocytes

Bioallethrin is an insecticide that is widely used to control mosquitoes, fleas and cockroaches. The widespread use of bioallethrin has resulted in both occupational and non-occupational human exposure. Bioallethrin enters blood, regardless of the route of exposure, where it can interact with erythrocytes. We have studied the effect of bioallethrin on isolated human erythrocytes under in vitro conditions. Erythrocytes were incubated with increasing concentrations of bioallethrin (10-200 μM) for 4 h at 37 °C. Several biochemical parameters were analyzed in bioallethrin treated and untreated (control) cells. Incubation of erythrocytes with bioallethrin increased protein oxidation, lipid peroxidation and depleted sulfhydryl group content. Membrane damage was evident from cell lysis, osmotic fragility, inhibition of bound enzymes and transmembrane electron transport system. Bioallethrin also increased hemoglobin oxidation, heme degradation and the release of free iron moiety. This will decrease the oxygen transporting ability of blood. Bioallethrin treatment altered the specific activities of antioxidant enzymes and diminished the antioxidant power of cells. Scanning electron microscopy showed that bioallethrin treatment also altered erythrocyte mophology. Almost all changes were in a bioallethrin concentration dependent manner. The cytotoxicity of bioallethrin is probably mediated by reactive oxygen and nitrogen species whose formation was significantly enhanced in treated erythrocytes. Thus bioallethrin enhances the generation of reactive species which cause oxidative damage of cell components in human erythrocytes.

Structural basis of pesticide detection by enzymatic biosensing: a molecular docking and MD simulation study

Designing of rapid, facile, selective, and cost-effective biosensor technology is a growing area for the detection of various classes of pesticides. The biosensor with these features can be achieved only through the various bio-components using different transducers. This study, therefore, focuses on the usage of molecular docking, specificity tendencies, and capabilities of proteins for the detection of pesticides. Accordingly, the four transducers, acetylcholinesterase (ACH), cytochromes P450 (CYP), glutathione S-transferase (GST), and protein kinase C (PKC) were selected based on their applications including neurotransmitter, metabolism, detoxification enzyme, and protein phosphorylation. Then after molecular docking of the pesticides, fenobucarb, dichlorodiphenyltrichloroethane (DDT), and parathion onto each enzyme, the conformational behavior of the most stable complexes was further analyzed using 50 ns Molecular Dynamics (MD) simulations carried out under explicit water conditions. In the case of protein kinase C (PKC) and cytochrome P450 3A4 enzyme (CYP), the fenobucarb complex showed the most suitable combination of free energy of binding and inhibition constant -4.42 kcal/mol (573.73 μM) and -5.1 kcal/mol (183.49 μM), respectively. Parathion dominated for acetylcholinesterase (ACH) with -4.57 kcal/mol (448.09 μM) and lastly dichlorodiphenyltrichloroethane for glutathione S-transferase (GST), -5.43 kcal/mol (103.88 μM). The RMSD variations were critical for understanding the impact of pesticides as they distinctively influence the energetic attributes of the proteins. Overall, the outcomes from the extensive analysis provide an insight into the structural features of the proteins studied, thereby highlighting their potential use as a substrate in biorecognition sensing of pesticide compounds.

Fabrication and evaluation of Au-Pd core-shell nanocomposites for dechlorination of diclofenac in water

Nanocomposites with core-shell structure usually exhibit excellent catalytic properties due to unique interfaces and synergistic effect among composites. In this study, Au-Pd bimetallic nanoparticles (NPs) with core-shell structure (Au-Pd cs) by using Au NPs as core and Pd as shell were successfully fabricated and, for the first time, were used to investigate the dechlorination of diclofenac (DCF) at H2 atmosphere in water at room temperature. The degradation products were studied as well by using HPLC/Q-ToF MS/MS. The operational factors such as pH and composition of the Au-Pd cs were also studied. The results showed that nearly 100% of DCF (30 mg L(-1), 50 mL, pH=7) was dechlorinated in 4.5 h by 10 mL of 56 mg L(-1) of Au-Pd cs. Ninety per cent of DCF was degraded in 6.5 h by the mixture of Au and Pd NPs. However, the individual Au NPs had no obvious effect in degrading DCF and the monometallic Pd NPs with comparable concentration only degraded less than 20% of DCF. Furthermore, the reaction mechanism of this catalytic process was studied in detail. It was found that the degradation was a second-order exponential reaction. The two main degradation products were obtained by cleaving the carbon-halogen bond of DCF and this made the degradation products more environmentally friendly.

The studies on the toxicity mechanism of environmentally hazardous natural (IAA) and synthetic (NAA) auxin--The experiments on model Arabidopsis thaliana and rat liver plasma membranes

This paper concerns the studies towards membrane-damage effect of two auxins: indole-3-acetic acid - IAA and 1-naphthaleneacetic acid - NAA on plant (Arabidopsis thaliana) and animal (rat liver) model membranes. The foregoing auxins are plant growth regulators widely used in agriculture to control the quality of the crop. However, their accumulation in the environment makes them hazardous for the living organisms. The aim of our investigations was to compare the effect of natural (IAA) vs. synthetic (NAA) auxin on the organization of plant and animal model membranes and find a possible correlation between membrane-disturbing effect of these compounds and their toxicity. The collected data evidenced that auxins cause destabilization of membranes, decrease their condensation and weakens interactions of molecules. The alterations in the morphology of model systems were also noticed. The foregoing effects of auxins are concentration-dependent and additionally NAA was found to act on animal vs. plant membranes more selectively than IAA. Interestingly, both IAA and NAA induce the strongest disordering in model lipid system at the concentration, which is frequently reported as toxic to animal and plants. Based on the above findings it was proposed that membrane-damage effect induced by IAA and NAA may be important from the point of view of the mechanism of toxicity of these compounds and cannot be ignored in further investigations in this area.

Biosensor technology for pesticides--a review

Pesticides, due to their lucrative outcomes, are majorly implicated in agricultural fields for crop production enhancement. Due to their pest removal properties, pesticides of various classes have been designed to persist in the environment over a longer duration after their application to achieve maximum effectiveness. Apart from their recalcitrant structure and agricultural benefits, pesticides also impose acute toxicological effects onto the other various life forms. Their accumulation in the living system may prove to be detrimental if established in higher concentrations. Thus, their prompt and accurate analysis is a crucial matter of concern. Conventional techniques like chromatographic techniques (HPLC, GC, etc.) used for pesticides detection are associated with various limitations like stumpy sensitivity and efficiency, time consumption, laboriousity, requirement of expensive equipments and highly trained technicians, and many more. So there is a need to recruit the methods which can detect these neurotoxic compounds sensitively, selectively, rapidly, and easily in the field. Present work is a brief review of the pesticide effects, their current usage scenario, permissible limits in various food stuffs and 21st century advancements of biosensor technology for pesticide detection. Due to their exceptional performance capabilities, easiness in operation and on-site working, numerous biosensors have been developed for bio-monitoring of various environmental samples for pesticide evaluation immensely throughout the globe. Till date, based on sensing element (enzyme based, antibody based, etc.) and type of detection method used (Electrochemical, optical, and piezoelectric, etc.), a number of biosensors have been developed for pesticide detection. In present communication, authors have summarized 21st century's approaches of biosensor technology for pesticide detection such as enzyme-based biosensors, immunosensors, aptamers, molecularly imprinted polymers, and biochips technology. Also, the major technological advancements of nanotechnology in the field of biosensor technology are discussed. Various biosensors mentioned in manuscript are found to exhibit storage stability of biocomponent ranging from 30-60 days, detection limit of 10(-6) - 10(-16) M, response time of 1-20 min and applications of developed biosensors in environmental samples (water, food, vegetables, milk, and juice samples, etc.) are also discussed. Researchers all over the globe are working towards the development of different biosensing techniques based on contrast approaches for the detection of pesticides in various environmental samples.

Determination of Insecticide Residues in Vegetal Fruits

Pesticides compounds represent an important class of pollutants for food, soil and surface water resources. Thus, a simplified method using gas chromatography was used for determining five insecticide residues in fruit samples produced in Ceará State (Brazil). The insecticides were simultaneously extracted from the fruit samples with a mixture of water-methanol (1 : 1% v/v) from lipid-containing crops and then reextracted with ethyl acetate. Cleanup by silica gel column chromatography was not necessary. The extracts were analyzed by GC-ECD. Analytical parameters, such as limit of detection (LOD), limit of quantification (LOQ), linearity, precision, and recovery were considered for the orange fruit. A sufficient recovery of 52.1, 57.0, 49.5, and 108.5% for parathion methyl, malathion, chlorpyrifos, and 2,4-dichlorophenol was found. The compounds 2,4-dichlorophenol, malathion, parathion methyl, and chlorpyrifos were found in all the fruit samples analyzed.

Phenoxyherbicides induce production of free radicals in human erythrocytes: Oxidation of dichlorodihydrofluorescine and dihydrorhodamine 123 by 2,4-D-Na and MCPA-Na

Although it is known that phenoxyacetic herbicides significantly affect the oxidative status of human erythrocytes, there is no direct evidence of their ability to induce free radical production. To demonstrate this phenomenon we investigated the effect of two commonly used phenoxyherbicides-sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D-Na) and sodium salt of 4-chloro-2-methylphenoxyacetic acid (MCPA-Na) on oxidation of dihydrorhodamine 123 and H(2)DCFDA as well as on carbonyl group content in cellular proteins. Moreover, haemoglobin denaturation was also measured. The rate of fluorescent probe oxidation was significantly higher for 2,4-D-Na, while both compounds exerted similar effects on protein carbonyl group (an increase in their content) and on denaturation of haemoglobin (no changes were observed). These results and the previous data led us to a conclusion that pro-oxidative action of phenoxyherbicides is strongly dependent on the localization of the substituent in the phenol ring. We also proposed a metabolic reaction chain that explains the mechanism of action of 2,4-D-Na in vivo.

Human erythrocytes are affected in vitro by extracts of Ugni molinae leaves

Ugni molinae Turcz, also known as "Murtilla", is a plant that grows in the south of Chile. Infusions of their leaves have long been used in traditional native herbal medicine. The chemical composition of the leaves indicates the presence of polyphenols, which have antioxidant properties. In order to evaluate the mechanisms of their antioxidant properties and the toxicity of the aqueous extracts of leaves, the extracts were induced to interact with human red cells, their isolated unsealed membranes (IUM) and large unilamellar vesicles (LUV) of dimyristoylphosphatidyltidylcholine (DMPC), representative of phospholipid classes located in the outer monolayer of the erythrocyte membrane. Scanning electron microscopy (SEM) observations indicated that the extracts achieved a significant alteration in the shape of the erythrocytes as they changed their discoid shape to echinocytes. According to the bilayer couple hypothesis, the shape change indicates that the polyphenols were located in the outer moiety of the red cell membrane. This conclusion was confirmed by the fluorescence experiments performed in IUM and DMPC LUV. In fact, the extracts produced slight initial increases followed by sharp decreases at higher concentrations in the anisotropy and general polarization parameters. These results imply that the extracts induced structural perturbations in the acyl chain and polar group packing arrangements of the erythrocyte IUM and DMPC LUV lipid bilayers: first ordering and afterwards disordering them as the extract concentration increased.