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BACKGROUND: The ginseng endophyte Paenibacillus polymyxa Pp-7250 (Pp-7250) has multifaceted roles such as preventing ginseng diseases, promoting growth, increasing ginsenoside accumulation, and degrading pesticide residues, however, these effects still have room for improvements. Composite fungicides are an effective means to improve the biocontrol effect of fungicides, but the effect of Pp-7250 in combination with its symbiotic bacteria on ginseng needs to be further investigated, and its mechanism of action has not been elucidated. In this study, a series of experiments was conducted to elucidate the effect of Paenibacillus polymyxa and Bacillus cereus co-bacterial agent on the yield and quality of understory ginseng, and to investigate their mechanism of action. RESULTS: The results indicated that P. polymyxa and B. cereus co-bacterial agent (PB) treatment improved ginseng yield, ginsenoside accumulation, disease prevention, and pesticide degradation. The mechanism is that PB treatment increased the abundance of beneficial microorganisms, including Rhodanobacter, Pseudolabrys, Gemmatimonas, Bacillus, Paenibacillus, Cortinarius, Russula, Paecilomyces, and Trechispora, and decreased the abundance of pathogenic microorganisms, including Ellin6067, Acidibacter, Fusarium, Tetracladium, Alternaria, and Ilyonectria in ginseng rhizosphere soil. PB co-bacterial agents enhanced the function of microbial metabolic pathways, biosynthesis of secondary metabolites, biosynthesis of antibiotics, biosynthesis of amino acids, carbon fixation pathways in prokaryotes, DNA replication, and terpenoid backbone biosynthesis, and decreased the function of microbial plant pathogens and animal pathogens. CONCLUSION: The combination of P. polymyxa and B. cereus may be a potential biocontrol agent to promote the resistance of ginseng to disease and improve the yield, quality, and pesticide degradation.

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Organophosphates constitute a major class of pesticides widely employed in agriculture to manage insect pests. Their toxicity is attributed to their ability to inhibit the functioning of acetylcholinesterase (AChE), an essential enzyme for normal nerve transmission. Organophosphates, especially chlorpyrifos, have been a key component of the integrated pest management (IPM) in onions, effectively controlling onion maggot Delia antiqua, a severe pest of onions. However, the growing concerns over the use of this insecticide on human health and the environment compelled the need for an alternative organophosphate and a potential microbial agent for bioremediation to mitigate organophosphate pesticide pollution. In the present study, chloropyrifos along with five other organophosphate insecticides, phosmet, primiphos-methyl, isofenphos, iodofenphos and tribuphos, were screened against the target protein AChE of D. antiqua using molecular modeling and docking techniques. The results revealed that iodofenphos showed the best interaction, while tribuphos had the lowest interaction with the AChE based on comparative binding energy values. Further, protein-protein interaction analysis conducted using the STRING database and Cytoscap software revealed that AChE is linked with a network of 10 different proteins, suggesting that the function of AChE is disrupted through interaction with insecticides, potentially leading to disruption within the network of associated proteins. Additionally, an in silico study was conducted to predict the binding efficiency of two organophosphate degrading enzymes, organophosphohydrolase (OpdA) from Agrobacterium radiobacter and Trichoderma harzianum paraoxonase 1 like (ThPON1-like) protein from Trichoderma harzianum, with the selected insecticides. The analysis revealed their potential to degrade the pesticides, offering a promising alternative before going for cumbersome onsite remediation.

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To explore the potential of probiotic candidates beneficial for honeybee health through the modulation of the gut microbiome, bee gut microbes were isolated from bumblebee (Bombus terrestris) and honeybee (Apis mellifera) using diverse media and cultural conditions. A total of 77 bee gut bacteria, classified under the phyla Proteobacteria, Firmicutes, and Actinobacteria, were identified. The antagonistic activity of the isolates against Ascosphaera apis, a fungal pathogen responsible for chalkbrood disease in honeybee larvae, was investigated. The highest growth inhibition percentage against A. apis was demonstrated by Bacillus subtilis strain I3 among the bacterial strains. The presence of antimicrobial peptide genes in the I3 strain was detected using PCR amplification of gene fragments encoding surfactin and fengycin utilizing specific primers. The export of antimicrobial peptides by the I3 strain into growth medium was verified using liquid chromatography coupled with mass spectroscopy. Furthermore, the strain's capabilities for degrading pesticides, used for controlling varroa mites, and its spent growth medium antioxidant activity were substantiated. The survival rate of honeybees infected with (A) apis was investigated after feeding larvae with only medium (fructose + glucose + yeast extract + royal jelly), (B) subtilis I3 strain, A. apis with medium and I3 strain + A. apis with medium. Honeybees receiving the I3 strain + A. apis exhibited a 50% reduction in mortality rate due to I3 strain supplementation under experimental conditions, compared to the control group. In silico molecular docking revealed that fengycin hydrolase from I3 strain effectively interacted with tau-fluvalinate, suggesting its potential in bee health and environmental protection. Further studies are needed to confirm the effects of the I3 strain in different populations of honey bees across several regions to account for genetic and environmental variations.

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Compared to monometallic nanoparticles, bimetallic nanoparticle synthesis and characterization have attracted more attention due to their superior environmental protection properties. In this study, we discuss the preparation and characterization of Cu-Zn bimetallic nanoparticles using Zinger extract, as well as their potential role in photocatalytic degradation of carbendazim, chlorpyrifos, monocrotophos, and cypermethrin. Surface properties were assessed with SEM and TEM, while UV-VIS, XRD, FTIR, and fluorescence spectroscopy were used to characterize the materials. It was observed that higher pH conditions were more conducive to the development of stable Cu-Zn BMNPs with diameters ranging from 60 to 100 nm. UV-VIS spectroscopy showed that the Cu-Zn bimetallic nanoparticles photodegraded 53-95% of the pesticides, monocrotophos, chlorpyrifos, and carbendazim during the 24-72-h incubation period. A number of pesticides may be photocatalytically degraded by primary reactive radicals produced by nanoparticles. We propose that the use of bimetallic nanoparticles could be one alternative strategy for pesticide mineralization.

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In this study, the non-edible part of oyster mushroom was utilized for quantitative removal of the most commonly used s-triazine herbicide; atrazine and its breakdown products including deethylatrazine (DEA), hydroxyatrazine (ATOH) and deisopropylatrazine (DIA) from aqueous samples. The functional groups available on the oyster mushroom were studied applying FTIR before and after adsorption. Experimental parameters influencing the uptake process including acidity, sorbent mass, sorption time, initial analyte quantities, and agitation speed were analysed and the maximum removal was found at 4, 0.3 g, 120 min, 0.5 mg L-1, and 150 rpm, respectively. Accordingly, the adsorption capacities of 0.994, 1.113, 0.991 and 1.016 mg g-1 were obtained for DIA, DEA, ATOH and atrazine, respectively. The adsorption characteristics were discussed utilizing Langmuir and Freundlich isotherm models. The fundamental characteristic of the Langmuir isotherm, which can be elaborated using separation factor or equilibrium parameter, RL, and coefficient of variation, R2, were (0.761, 0.996), (0.884, 0.975), (0.908, 0.983) and (0.799, 0.984) for DIA, DEA, ATOH and Atrazine, respectively. These findings showed that all analytes' adsorption processes were fitted well to the Langmuir adsorption isotherm, indicating that the adsorbent surface was covered in a monolayer. The kinetics was also evaluated using the pseudo-first and pseudo-second order models. The coefficient of determination, r2, were found to be 0.09703, 0.9989, 0.9967 and 0.9998 for DIA DEA, ATOH and atrazine, respectively, for pseudo-second order, signifying that, all analytes were found to follow the pseudo-second order rate model showing that the rate limiting step is chemisorption in the sorption process. Based on these findings, the non-edible and disposable part of the oyster mushrooms can be utilized as a preferred alternative biosorbent for the uptake of the target compounds analysed and other pollutants possessing comparable physicochemical characteristics occurring in various water bodies.

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Plant-wearable sensors provide real-time information that enables pesticide inputs to be finely tuned and play critical roles in precision agriculture. However, tracking pesticide information in living plants remains a formidable challenge owing to inadequate shape adaptabilities and low in-field sensor sensitivities. In this study, plant-wearable hydrogel discs are designed by embedding a dual-shelled upconversion-nanoparticles@zeolitic-imidazolate-framework@polydopamine (UCNPs@ZIF@PDA) composite in double-network hydrogels to deliver on-site pesticide-residue information. Benefiting from the enzyme-mimetic catalytic activity of ZIFs and enzyme triggered-responsive property of PDA shell, the hydrogel discs are endowed with high sensing sensitivity toward 2,4-dichlorophenoxyacetic acid pesticide at the nanogram per milliliter level via boosting fluorescence quenching efficiency. Notably, hydrogel discs mounted on tomato plants exhibit sufficient adaptability to profile dynamic pesticide degradation when used in conjunction with an ImageJ processing algorithm, which is practically applicable. Such hydrogel discs form a noninvasive and low-cost toolkit for the on-site acquisition of pesticide information, thereby contributing to the precise management of the health status of a plant and the judicious development of precision agriculture.

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Water, soil, and food products contain pesticide residues. These residues result from excessive pesticides use, motivated by the fact that agricultural productivity can be increased by the use of these pesticides. The accumulation of these residues in the body can cause health problems, leading to food safety concerns. Cold plasma technology has been successfully employed in various applications, such as seed germination, bacterial inactivation, wound disinfection, surface sterilization, and pesticide degradation. In recent years, researchers have increasingly explored the effectiveness of cold plasma technology in the degradation of pesticide residues. Most studies have shown promising outcomes, encouraging further research and scaling-up for commercialization. This review summarizes the use of cold plasma as an emerging technology for pesticide degradation in terms of the plasma system and configuration. It also outlines the key findings in this area. The most frequently adopted plasma systems for each application are identified, and the mechanisms underlying pesticide degradation using cold plasma technology are discussed. The possible factors influencing pesticide degradation efficiency, challenges in research, and future trends are also discussed. This review demonstrates that despite the nascent nature of the technology, the use of cold plasma shows considerable potential in regards to pesticide residue degradation, particularly in food applications.

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The fungicide iprodione (IPR) (3-(3,5-dichlorophenyl) N-isopropyl-2,4-dioxoimidazolidine-1-carboxamide) is a highly toxic compound. Although IPR has been restricted, it is still being applied in many places around the world, constituting an environmental risk. The biodegradation of IPR is an attractive option for reducing its residues. In this study, we isolated thirteen IPR-tolerant bacteria from a biopurification system designed to treat pesticides. A study of biodegradation using different strains was comparatively evaluated, and the best degradation rate of IPR was presented by Achromobacter sp. C1 with a half-life (T1/2) of 9 days. Based on a nano-LC-MS/MS analysis for the strains, proteins solely expressed in the IPR treatment were identified by highlighting the strain Achromobacter sp. C1, with 445 proteins primarily involved in the biosynthesis of secondary metabolites and microbial metabolism in diverse environments. Differentially expressed protein amidases were involved in six metabolic pathways. Interestingly, formamidase was inhibited while other cyclases, i.e., amidase and mandelamide hydrolase, were overexpressed, thereby minimizing the effect of IPR on the metabolism of strain C1. The dynamic changes in the protein profiles of bacteria that degrade IPR have been poorly studied; therefore, our results offer new insight into the metabolism of IPR-degrading microorganisms, with special attention paid to amidases.

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Herbicide mixtures are a new and effective agricultural strategy for managing suppress weed resistance and have been widely used in controlling weeding growth in maize fields. However, the potential ecotoxicological impact of these mixtures on the microbial community structure and function within various root-associated niches, remains inadequately understood. Here, the effects of nicosulfuron, mesotrione and atrazine on soil enzyme activity and microbial community structure and function were investigated when applied alone and in combination. The findings indicated that herbicide mixtures exhibit a prolonged half-life compared to single herbicides. Ecological niches are the major factor influencing the structure and functions of the microbial community, with the rhizosphere exhibiting a more intensive response to herbicide stress. Herbicides significantly inhibited the activities of soil functional enzymes, including dehydrogenase, urease and sucrose in the short-term. Single herbicide did not drastically influence the alpha or beta diversity of the soil bacterial community, but herbicide mixtures significantly increased the richness of the fungal community. Meanwhile, the key functional microbial populations, such as Pseudomonas and Enterobacteriaceae, were significantly altered by herbicide stress. Both individual and combined use of the three herbicides reduced the complexity and stability of the bacterial network but increased the interspecific cooperations of fungal community in the rhizosphere. Moreover, by quantification of residual herbicide concentrations in the soil, we showed that the degradation period of the herbicide mixture was longer than that of single herbicides. Herbicide mixtures increased the contents of NO3--N and NH4+-N in the soil in the short-term. Overall, our study provided a comprehensive insight into the response of maize root-associated microbial communities to herbicide mixtures and facilitated the assessment of the ecological risks posed by herbicide mixtures to the agricultural environment from an agricultural sustainability perspective.

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Cold plasma processing is a nonthermal approach that maintains food quality while minimizing the effects of heat on its nutritious qualities. Utilizing activated, highly reactive gaseous molecules, cold plasma processing technique inactivates contaminating microorganisms in food and packaging materials. Pesticides and enzymes that are linked to quality degradation are currently the most critical issues in the fresh produce industry. Using cold plasma causes pesticides and enzymes to degrade, which is associated with quality deterioration. The product surface characteristics and processing variables, such as environmental factors, processing parameters, and intrinsic factors, need to be optimized to obtain higher cold plasma efficiency. The purpose of this review is to analyse the impact of cold plasma processing on qualitative characteristics of food products and to demonstrate the effect of cold plasma on preventing microbiological concerns while also improving the quality of minimally processed products.

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Pesticides are the most cost-effective means of pest control; however, the serious concern is about the non-target effects due to their extensive and intensive use in both agricultural and non-agricultural settings. The degradation rate constant (k) and half-life (DT50) of four commonly used pesticides, glyphosate, 2,4-D, chlorothalonil and dimethoate were determined in five Australian urban landscape soils, with varying physicochemical characteristics, to assess their environmental and human health risks. The k values (day-1) for the selected pesticides were inversely proportional to those of organic carbon (OC), silt, clay and Fe and Al oxides, and directly proportional to pH and sand content in soils. In contrast, the calculated values of DT50 (days) of all the four pesticides in five soils positively correlated with OC, clay, silt and oxides of Fe and Al, whereas soil pH and sand content exhibited a negative correlation. The calculated values of environmental indices, GUS and LIX, for the selected pesticides indicate their potential portability into water bodies, affecting non-target organisms as well as food safety. The evaluation for human non-cancer risk of these pesticides, based on the calculated values of hazard quotient (HQ) and hazard index (HI), suggested that exposure of adults and children to soils, contaminated with 50% of initially applied concentrations, through ingestion, dermal and inhalation pathways might cause negligible to zero non-carcinogenic risks. The present data might help the stakeholders in applying recommended doses of pesticides in urban landscapes and regulatory bodies concerned in monitoring the overall environmental quality and implementing safeguard policies. Our study also clearly demonstrates the need for developing improved formulations and spraying technologies for pesticides to minimize human and environmental health risks.

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Thiram (tetramethylthiuramdisulfide) or thiram sulphide is a dithiocarbamate group of non-systemic group of fungicide which are applied for seed treatment, control of the crop pests, to repel animals, etc. Moreover, thiram has also been responsible to cause moderate skin sensitivity and eye irritation. Higher exposure to thiram might also lead to developmental damages to newborn and neurotoxic effects to non-target organisms. Advancing to prevent such toxic effects and prevention of soil fertility from thiram and thiram-like chemicals is indispensable. The analytical High-Performance Thin-Layer Chromatography (HPTLC) is a simple, quick and a reliable method was proposed and validated for the detection and quantification of various small molecules for many years. This manuscript represents the solution to use microbes to degrade the thiram present in the soil and for that, HPTLC based method to study thiram degradation by Pseudomonas has been designed. Herein, a HPTLC protocol formalised to reveal the detection and quantification of thiram within the range of 100 to 700 ng/spot on TLC plate. The same concentration was then used for calculating percent microbial degradation of thiram from the culture broth. To perform the microbial degradation of thiram, Pseudomonas otitidis strain TD-8 and Pseudomonas stutzeri strain TD-18 were taken as thiram degrader microbial strain. The efficacy of TD-8 to degrade thiram was identified to be 81 and 99% when grown in presence of thiram for 4 days and 8 days, respectively, while TD-18 strain's efficacy to degrade thiram was found to be 57% and 99% when grown in presence of thiram for 4 days and 8 days, respectively.

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Potassium (K) and phosphorus (P) are the important macronutrients needed for the plant development, but it is widely present in an insoluble form for the plant's uptake. In order to increase the productivity, biofertilisers play crucial role in plant growth enhancement. Our present work focused to isolate potassium-phosphate solubilizing bacteria from the agricultural soil of tomato cultivated soil. Potassium and phosphate solubilization and degradation of monocrotophos was estimated spectrophotometrically. Out of thirteen isolates, two isolates proved to be the best P and K solubilizers. The bacterial isolates (SDKVG02 and SDKVG04) were optimized to obtain maximum P and K solubilization of 57.5 mg L-1 and 15.07 mg L-1 by the isolates. Pot experiments were conducted using SDKVG 02 and 04, immobilized on carrier materials, peat proving the best carrier with the total average green gram and chick pea length of 11.66 ± 0.0666 22.22 ± 0.0577. The MCP degradation percentage was achieved at 80 ppm of MCP with 75.8% and 64.10% by SDKVG 02 and SDKVG 04. Furthermore, production of organic acids such as malic acid, phthalic acid, ascorbic acid, nicotinic acid, and tartaric acid paves solubilization of P and K. The isolates were recognized based on 16S rRNA gene sequencing as Enterobacter hormaechei- SDKVG-02, Enterobacter cloacae SDKVG- 04. The KSB-PSB isolates also express N-fixing activity which is proved through In-silico analysis. It is worth to highlight SDKVG 02 and 04 would be potent biofertiliser exploited in increasing the soil fertility and crop productivity as well in degradation of monocrotophos present in the soil.

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Long-term use of toxic pesticides in agricultural grounds has led to adverse effects on the environment and human health. Microbe-mediated biodegradation of pollutants is considered an effective strategy for the removal of contaminants in agricultural and environmental sustainability. Imidacloprid, a neonicotinoid class of pesticides, was widely applied insecticide in the control of pests in agricultural fields including the tea gardens of Assam. Here, native bacteria from imidacloprid contaminating tea garden soils were isolated and screened for imidacloprid degradation efficiency under laboratory conditions. Out of the 30 bacterial isolates, 4 were found to tolerate high concentrations of imidacloprid (25,000 ppm), one of which isolate MBSB-12 showed the highest efficiency for imidacloprid tolerance and utilization as the sole carbon source. Morphological, biochemical, and 16 S ribosomal RNA gene sequencing-based characterization revealed the isolate as Pseudomonas plecoglossicida MBSB-12. The isolate reduced 87% of extractable imidacloprid from the treated soil in 90 days compared to the control soil (without bacterial treatment). High-Resolution Mass Spectrometry (HRMS) analysis indicated imidacloprid breakdown to comparatively less harmful products viz., imidacloprid guanidine olefin [m/z = 209.0510 (M + H)+], imidacloprid urea [m/z = 212.0502 (M + H)+] and a dechlorinated degraded product of imidacloprid with m/z value 175.0900 (M + H)+. Further investigation on the molecular machinery of P. plecoglossicida MBSB-12 involved in the degradation of imidacloprid is expected to provide a better understanding of the degradation pathway.

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Benefiting from the stimuli-responsive property and powerful loading capacity, functionalized hydrogels are favorable for the fabrication of sensing devices. Herein, we design aggregation-induced emission (AIE)-active hydrogel discs by embedding gold nanoclusters@zeolite-like imidazole framework (AuNCs@ZIF) composites in double-network hydrogels to build a sensitive pesticide biosensor. The hydrogel discs integrate an AIE effect of AuNCs, a stimuli-responsive property of ZIF, and a porous network structure of the hydrogel, which enhances the sensing sensitivity via boosting the stable fluorescent signal and antifouling performance. In conjunction with a homemade device, the fluorescence images of hydrogel discs could be transduced into data information for accurate quantification of chlorpyrifos pesticide with a detection limit of 0.2 ng/mL. The dynamic degradation of chlorpyrifos in Chinese cabbage is demonstrated to confirm the practical application of hydrogel discs. Such AIE-active hydrogel discs could be a plant health sensor for the on-site quantification of pesticide residues on crops, holding great promise for precision agriculture.

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A new sensitive and selective methods was developed to quantify different types of pesticides and their degradation products in sediment. The method developed was optimized and modified based on the accelerated solvent extraction, followed by the solid-phase extraction clean-up technique. High-performance liquid chromatography coupled with mass spectrometry was used for analysis. The influence of various parameters on the extraction process was investigated, including the extraction temperature, extraction solvent, purification column and purification solvent, etc. Under the optimal conditions, the relative recoveries of the pesticides and their degradation products ranged from 80 to 106% for spiked blank sediment and environmental sediment samples with relative standard deviations of 1-9%. The method displayed low method detection limits for both sediment matrices and achieved good linearity over the tested range of concentrations. The physical and chemical properties of sediment showed that high content of sediment water content and humic acid would affect the extraction efficiency of sample pretreatment. The method was applied to environmental sediment to quantify pesticide residues in the samples. Based on the instrument and method performance validation results, the developed methods can be applied in environmental pesticide residue analysis, thus providing a scientific method for the detection of sediment samples.

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Microbes are crucial in removing various xenobiotics, including pesticides, from the environment, specifically by mineralizing these hazardous pollutants. However, the specific procedure of microbe-mediated pesticide degradation and its consequence on the environment remain elusive owing to limitations in culturing techniques. Therefore, in this study, we have investigated i) the physicochemical and elemental compositions of PCAS (pesticide-contaminated agricultural soils) and NS (natural soils); ii) the bacterial communities and degradation pathways, as well as some novel biodegradation genes (BDGs) and pesticide degradation genes (PDGs) across two different landscapes (PCAS and NS) by applying high-throughput sequencing. The chemical and elemental composition analyses showed that all nutrients (P, K, N, S, Mn, B, and Zn) were significantly higher in PCAS than in NS (p ≤ 0.05). The results of the 16S rRNA amplicon sequencing analysis of pesticide-contaminated (PCAS-1, PCAS-2, PCAS-3, PCAS-4) samples showed that the relative abundance of the phylum Proteobacteria (30-36%) > Actinobacteria (15-20%) > Firmicutes (13-14%) > Bacteroidetes (7-13%), were higher compared to the natural soil (NS-1, NS2). Consistent with this, a phylogenetic shift was observed with (alpha, beta, and gamma Proteobacteria) being abundant in PCAS, whereas delta and epsilon groups were more prevalent in NS. The functional characterization of the PCAS and NS by PICRUSt2 revealed that bacterial communities play a significant role in pesticide metabolism. Predictive metagenome analysis of contaminated soils showed the role of core degrading genes in membrane transport, stress response, regulatory genes, resource transport, and environmental sensing. Furthermore, 14 BDGs and 30 PDGs were examined, with a relative abundance of 0.081-1.029 % and 0.107-0.8903 % in each PCAS, respectively. The major BDGs and PDGs, with the compounds they hydrolyze, include ppo (polyphenol oxidase and laccase), CYP (cytochrome p450 protein), lip gene (lignin peroxidase), similarly, among the PDGs mhel (carbendazim), opd (organophosphate), mpd (methyl parathion), atzA, atzB, atzD, atzF and trzN (atrazine), chd (chlorothalonil), hdx (metamitron), hdl-1 (isoproturon) and fmo (nicosulfuron). Overall, our findings demonstrated the significance of utilizing metagenomic methods to predict microbial aided degradation in the ecology of contaminated environments.

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Oxygenases, which catalyze the reductive activation of O2 and incorporation of oxygen atoms into substrates, are widely distributed in aerobes. They function by switching the redox states of essential cofactors that include flavin, heme iron, Rieske non-heme iron, and Fe(II)/α-ketoglutarate. This review summarizes the catalytic features of flavin-dependent monooxygenases, heme iron-dependent cytochrome P450 monooxygenases, Rieske non-heme iron-dependent oxygenases, Fe(II)/α-ketoglutarate-dependent dioxygenases, and ring-cleavage dioxygenases, which are commonly involved in pesticide degradation. Heteroatom release (hydroxylation-coupled hetero group release), aromatic/heterocyclic ring hydroxylation to form ring-cleavage substrates, and ring cleavage are the main chemical fates of pesticides catalyzed by these oxygenases. The diversity of oxygenases, specificities for electron transport components, and potential applications of oxygenases are also discussed. This article summarizes our current understanding of the catalytic mechanisms of oxygenases and a framework for distinguishing the roles of oxygenases in pesticide degradation.

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MXenes are a quickly growing and extended group of two-dimensional (2D) substances that have earned unbelievable analysis credits for various application areas within different manufacturing areas. Due to novel essential architectural and physicochemical properties shows good properties, such as elevated exterior area, living adaptability, strong electrochemistry, and great hydrophilicity. Given the fast progress within the structure and synthesis of MBNs for water treatment, quick updates on this research field are required to remove toxic substances, such as production approaches and characterization methods for the advantages and constraints of MXenes for pollutant degradation. MXenes are determined as a proposed road toward atmosphere-clean-up machinery to identify and decrease a pattern of hazardous resistant pollutants from environmental forms. Here, in this review article, we have been focused on describing the overview, novel synthesis methods, and characteristics of the MXene-based nanomaterials (MBNs) in the field for removing hazardous contaminants from environmental conditions. In the last, the utilizations of MBNs in water sanitization, organic solvent filtration, antibiotics degradation, pesticide degradation, heavy metals degradation, ions removal, bacterial pathogens degradation, along with the conclusion, challenges, and prospects in this field, have been discussed.

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Diverse glutathione-S-transferases (GSTs) are produced by insect pests including Helicoverpa armigera (HaGSTs) for detoxification of insecticides or xenobiotic compounds that they encounter. In an earlier study, the HaGST-8 gene was isolated from H. armigera larvae exposed to pesticide mixtures and the recombinant protein was expressed in the yeast Pichia pastoris. In this investigation, HaGST-8 was successfully immobilized on glutaraldehyde-activated APTES functionalized silica nanoparticles to obtain SiAPT-HaGST-8 nano-conjugates. Although enzyme activity associated with these conjugates was comparable to that of free HaGST-8, the specific activity of the former was found to be 1.25 times higher than the latter. In comparison with the free enzyme (that demonstrated a pH optimum of 9.0), for the nano-conjugates, the pH range was extended between pH 8.0 to 9.0. The optimum temperature for activity of both forms of the enzyme was found to be 30 °C. Stability of the enzyme was improved from 20 d for free HaGST-8 to 30 d for SiAPT-HaGST-8 nano-conjugates. Some loss in GST activity was detected after every reuse cycle of nano-conjugates and in all, 63% reduction was observed after three cycles. When 3 kinds of pesticides (namely, chlorpyrifos, dichlorvos and cypermethrin) were reacted with SiAPT-HaGST-8, more than 80% reduction in levels were observed. On the basis of the results obtained, the use of such silica nanoparticle-based systems for stable enzyme conjugation followed by effective removal of pesticides from aqueous media is envisaged.

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