Metal-organic framework nanoparticles (MOF NPs) have received much attention for their potential use in nanopesticides. However, little is known about the potential health and environmental risks associated with these materials. In this study, the toxicological responses of zebrafish exposed to five MOF NPs for short and long periods of time were evaluated.
View Article and Find Full Text PDFCarbohydr Polym
February 2023
In this study, pH-responsive LC@O-CMCS/PU nanoparticles were prepared by encapsulating λ-cyhalothrin (LC) with O-carboxymethyl chitosan (O-CMCS) to form LC/O-CMCS and then covering it with polyurethane (PU). Characterization and performance test results demonstrate that LC@O-CMCS/PU had good alkaline release properties and pesticide loading performance. Compared to commercial formulations containing large amounts of emulsifiers (e.
View Article and Find Full Text PDFIn this work, an enzyme-responsive nanovehicle for improving captan (CAP) contact fungicide bioactivity and translocation in plant tissues was synthesized (CAP-MSNs-β-glucan) by attaching β-glucan to the outer surface of mesoporous silica nanoparticles. CAP-MSNs-β-glucan properties were tested by FTIR, ζ-potential, DLS, XRD, TGA, FE-SEM, and HR-TEM. Cargo protection ability of CAP-MSNs-β-glucan from photolysis and hydrolysis was examined in comparison to CAP commercial formulation (CAP-CF).
View Article and Find Full Text PDFUnderstanding the lethal effects of pesticides nano formulations on the targeted organisms (pathogens) and the non-targeted organisms (fish, earthworms, etc) is essential in assessing the probable impact of new technologies on agriculture and environment. Here we evaluated the bioactivity and the biotoxicity of new type of fungicide smart-delivery formulation based on conjugating carboxymethylated-β-glucans on the mesoporous silica nanoparticles (MSNs) surface after loading chlorothalonil (CHT) fungicide in the MSNs pores. The obtained formulation has been characterized with FE-SEM, and HR-TEM.
View Article and Find Full Text PDFIn this study, a pesticide controlled release system with dual response characteristics of pH and enzyme triggering was developed. Indoxacarb (IDC) was loaded into hollow mesoporous silica (HMS) nanoparticles, carboxylated β-cyclodextrin (β-CD) acted as a capping molecule to couple with the amino-functionalized HMS, and their well-defined morphological structures were confirmed by scanning electron microscopy and transmission electron microscopy. The results showed that the prepared IDC loaded HMS-CD had high loading efficiency (26.
View Article and Find Full Text PDFBackground: Water hyacinth (Eichhornia crassipes) is considered the most damaging aquatic weed in many countries. Chemical methods are still the primary approach to control, although this directly exposes the natural enemy of water hyacinth (water hyacinth weevil) to herbicides. In addition, spray drift can easily damage non-target plants.
View Article and Find Full Text PDFIn previous articles, it was found that epoxiconazole enantiomers can persist for a long time in the environment, causing severe environmental damage. Herein, we investigated alterations in the soil microbial community and rat gut microbiota after six weeks of treatment with rac-epoxiconazole or one of its enantiomers. The selected concentrations were 1, 2, and 6 times greater than the maximum residue limits (MRLs).
View Article and Find Full Text PDFFosthiazate is a widely used chiral organophosphorous nematicide with four stereoisomers. The present study systemically assessed the stereoselectivity of fosthiazate for the first time, including absolute configuration confirmation, stereoselective bioactivity toward nematode and aphid, toxicity to honeybees, and stereoselective degradation in cucumber and pepper under field conditions. The absolute configurations of the four stereoisomers that eluted on the Superchiral IG-3 column were confirmed as (1,3)-(-)-fosthiazate, (1,3)-(-)-fosthiazate, (1,3)-(+)-fosthiazate, and (1,3)-(+)-fosthiazate.
View Article and Find Full Text PDFSci Total Environ
August 2020
Bitertanol is a widely used chiral triazole fungicide. The stereoselective environmental behavior and biological effects of bitertanol are not clear. The present study evaluated the stereoselectivity of bitertanol, including its degradation in five typical soils (under laboratory controlled aerobic, anaerobic and sterilization conditions), metabolism in rat liver microsomes (RLM; in vitro), and the endocrine disruption effects on the estrogen receptor (ER) and thyroid hormone receptor (TR) using reporter gene assays.
View Article and Find Full Text PDFTo clarify the environmental behaviour and bioactivity of epoxiconazole enantiomers, an integrated assessment has been done. The degradation in soil, water, and river-sediments were studied. The toxicity to Chlorella vulgaris and Daphnia magna was also examined.
View Article and Find Full Text PDFPestic Biochem Physiol
October 2019
Chiral triazole fungicides have played a significant role in plant pathogen control. Although their enantiomers often exhibit different bioactivity, the mechanism of the stereoselectivity has not been well studied. The stereoselective bioactivity and mechanisms of prothioconazole and its chiral metabolite against plant pathogenic fungi were investigated.
View Article and Find Full Text PDFCyproconazole, a chiral triazole fungicide, has been diffusely used and analyzed. The development of an effective analytical method for cyproconazole enantiomers can support their residual monitoring and risk assessment. In the present study, the absolute configuration of the cyproconazole enantiomers was confirmed by electronic circular dichroism and time-dependent density functional theory.
View Article and Find Full Text PDFPest Manag Sci
January 2020
Background: The chiral pesticide bitertanol has been widely used in the prevention and treatment of fungal diseases on many crops. However, research on bitertanol at the stereoisomer level has not been reported. Here, we study the stereoselective bioactivity, toxicity, and degradation of this pesticide under laboratory and field conditions.
View Article and Find Full Text PDFThe wide use of chiral fungicides has generated interest in the stereoselectivity of their ecotoxicological effects. However, there are few studies about the potential endocrine-disrupting effects (EDEs) of chiral fungicides. This study evaluated the hormone receptor activities of the chiral triazole fungicide prothioconazole and its metabolite using reporter gene assays.
View Article and Find Full Text PDFIsofenphos-methyl (IFP) is a very active and persistent chiral insecticide. However, IFP has lower activity against acetylcholinesterases (AChEs). Previously, it was confirmed that phosphorothioate organophosphorus pesticides with N-alkyl (POPN) require activation by oxidative desulfuration and N-dealkylation.
View Article and Find Full Text PDFThe enantiomeric environmental behaviors, bioactivities and toxicities of isofenphos‑methyl enantiomers were characterized systematically in this study. (R)‑Isofenphos‑methyl was degraded preferentially in Yangtze River water and different types of vegetables with an enantiomeric fraction (EF) of 0.6 to 0.
View Article and Find Full Text PDFα-Amylase-responsive carrier for controlled release of avermectin (AVM) was prepared based on α-cyclodextrin (α-CD) anchored hollow mesoporous silica (HMS) using α-CD as a capping molecule. The release of AVM was studied at different temperatures, pH values and in the presence or absence of α-amylase. The results revealed that the AVM-encapsulated controlled release formulation (AVM-CRF) has a drastic enzymatic dependence, an excellent encapsulation efficacy reaching 38%, and outstanding UV and thermal shielding ability.
View Article and Find Full Text PDFJ Agric Food Chem
September 2017
In the present study, enzymatic responsive controlled release formulations (CRFs) were fabricated. The CRFs were achieved by anchoring mechanically interlocked molecules using α-cyclodextrin onto the surface pore rims of hollow mesoporous silica (HMS). The CRFs were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis.
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