JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2020
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IF 4.192
Qing Zhou,Xu Zhang,Zhong Wu
The effects of TiO2 and ZnO nanoparticles on soil bacteria and enantioselective transformation of racemic-metalaxyl (rac-metalaxyl) in agricultural soil with or without Lolium perenne were investigated in an outdoor greenhouse. After a 70-day exposure to 2‰ ZnO, microbial biomass carbon decreased by 66% and bacterial community composition significantly changed. Meanwhile, ZnO decreased chlorophyll cumulation in L. perenne by 34%. ZnO also inhibited the enantioselective transformation of metalaxyl enantiomers and changed the enantiomer fraction of metalaxyl. TiO2 showed similar effects but to a lesser extent. L. perenne promoted the transformation of rac-metalaxyl and ingested TiO2 and ZnO. L. perenne changed the bacterial co-occurrence networks and biomarkers in native soil and soil exposed to TiO2 and ZnO. L. perenne reduced the inhibition effects of TiO2 and ZnO on the transformation of rac-metalaxyl. The decrease in the relative abundance of soil keystone taxa such as Acidobacteria and Gemmatimonas might respond to the corresponding slow transformation of rac-metalaxyl in soils exposed to TiO2 and ZnO, regardless of L. perenne. Our results demonstrated the existence of mutual interactions among the impact of engineered nanoparticles on different components (microbes, plants, and coexisting pollutants) in the terrestrial ecosystem.
研究领域:
环境科学
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微生物学
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植物科学
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土壤科学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
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2022
·Vol. 46
·期 2
·171-181
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IF 3.434
Zhang Yin-Jun,Wei Li-Tian,Zhou Ming-Peng,Wei Chun,Yu Xin-Jun
( R )-N-(2,6-dimethylphenyl) aminopropionic acid methyl ester (( R )-DMPM) is an important chiral intermediate of the fungicide N-(2,6-Dimethylphenyl)-N-(methoxyacetyl)-alanine methyl ester (( R )-Metalaxyl). In this study, (1) D3520 (macroporous acrylic anion resin), selected from the ten resins, was used to immobilize the esterase from Pseudochrobactrum asaccharolyticum WZZ003 (PAE07) for resoluting the ( R,S )-DMPM to obtain ( R )-DMPM. (2) Up to 20 g/L PAE07 could be immobilized onto D3520 with a high enzymatic activity of 32.4 U/g. Moreover, the Km and Vmax values of 19.1 mM and 2.8 mM/min for D3520-immobilized PAE07 indicated its high activity and stereoselectivity. (3) The optimal temperature and pH for the immobilized PAE07 were 40 ℃ and 8.0, and substrate concentration was up to 0.35 M. After 15 h reaction, the conversion rate from ( R,S )-DMPM to ( R )-DMPM was 48.0% and the e.e.p and E values were 99.5% and 1393.0, respectively. In scale-up resolution, 200 g/L substrate and 12.5 g immobilized esterase PAE07 condition, a conversion rate from substrate to product of 48.1% and a product e.e.p of 98% were obtained within 12 h, with the activity of immobilized PAE07 retained 80.2% after 5 cycles of reactions. These results indicated that the D3520-immobilized esterase PAE07 had great potential for enzymatic resolution of ( R,S )-DMPM to prepare ( R )-Metalaxyl.
研究领域:
生物化学
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酶工程
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有机合成
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2016
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IF 2.857
Chuanzhou Liang,Junxing Huang,Xu Zhang
The adsorption coefficient of racemic metalaxyl onto an agriculture soil was small and nonenantioselective. Biotransformation was the predominant pathway for the elimination of R-metalaxyl, while abiotic and biotransformation made a comparable contribution to the degradation of S-metalaxyl. Metalaxyl acid was the main transformation intermediate. The enantiomer fraction of metalaxyl decreased with an increase in its initial spike concentration or the presence of the co-constituents in metalaxyl commercial products. Under simulated solar irradiation, the presence of TiO2 promoted the overall transformation kinetics through enhanced biotransformation and extra photoinduced chemical reactions. The promotion was enantioselective and thereafter changed the enantiomer fraction. The results obtained in this study showed that some achiral parameters, although they have no direct impact on enantioselective reactions with enantiomers, can significantly affect the enantioselective transformation of racemic metalaxyl. Thus, our results indicate that the contribution of chemical interactions on the enantioselective transformation of chiral pesticides may be underestimated.
研究领域:
环境科学
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农业科学
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DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2017
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IF 5.099
Junxing Huang,Chuanzhou Liang,Xu Zhang
The application of nanotechnology in agriculture, pesticide delivery and other related fields increases the occurrence of engineered nanoparticles (ENPs) in soil. Since ENPs have larger surface areas and normally a high adsorption capacity for organic pollutants, they are thought to influence the transport of pesticides in soils and thereafter influence the uptake and transformation of pesticides. The adsorption pattern of racemic-metalaxyl on agricultural soils including kinetics and isotherms changed in the presence of nano-SiO 2 . The adsorption of racemic-metalaxyl on agricultural soil was not enantioselective, in either the presence or the absence of SiO 2 . The adsorption of racemic-metalaxyl on SiO 2 decreased to some extent in soil-SiO 2 mixture, and the absolute decrease was dependent on soil properties. The decreased adsorption of metalaxyl on SiO 2 in soil-SiO 2 mixture arose from the competitive adsorption of soil-dissolved organic matter and the different dispersion and aggregation behaviors of SiO 2 in the presence of soil. Interactions between SiO 2 and soil particles also contributed to the decreased adsorption of metalaxyl on SiO 2 , and the interactions were analyzed by extended Derjaguin–Landau–Verwey–Overbeek theory. The results showed that the presence of nano-particles in soils could decrease the mobility of pesticides in soils and that this effect varied with different soil compositions.
研究领域:
环境科学
·
土壤学
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DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2017
·
IF 3.743
Wei Xie,Fangxing Yang
Although enantioselective accumulation of chiral pesticide has been reported in organisms, the mechanisms remain unclear. In this study, the effects of chiral pesticide metalaxyl on CYP1A1, CYP1A2, CYP2B1, CYP2B2, CYP2E1 and CYP3A were investigated in human hepatoma HepG2, rat hepatic H4IIE, chicken hepatic LMH and grass carp hepatic L8824 cells. Moreover, the residual concentrations and enantiomeric ratios (ERs) of metalaxyl were also detected in the medium. The results showed the responses of these CYP450s to metalaxyl were enzyme-dependent and species-dependent in the four cells. CYP1A1, CYP1A2, and CYP2B1 were induced in HepG2 cells, CYP2A1 and CYP2B1 were induced in H4IIE cells, CYP1A1 and CYP2B1 were induced in LMH cells, and CYP2B1 was induced in L8824 cells. The enantioselective residual of metalaxyl was detected in the medium and found to be species-specific. HepG2, H4IIE and LMH cells were inclined to attenuate S -metalaxyl and lead to decrease of ER of metalaxyl, while L8824 cells were inclined to remove R -metalaxyl and resulted in an inverse shift of ER. These findings suggest an enantioselective metabolism of metalaxyl in various species which is not only related with CYP450s and CYP450 enzyme-specific, but also species-specific.
研究领域:
环境科学
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毒理学
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药理学
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DOI
PubMed
高影响因子
ACS Omega
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2020
·
IF 2.87
Ping Ni,Liqiang Liu,Changlong Hao,Xinxin Xu,Shanshan Song,Hua Kuang,Chuanlai Xu
In this study, we prepared a monoclonal antibody (mAb) against metalaxyl (Met) with a half-maximum inhibitory concentration (IC50) of 0.54 ng/mL based on a new hapten, and a gold nanoparticle-based immunochromatographic assay (GICA) was developed for the rapid detection of Met residues in tobacco. Under optimal conditions, even with the naked eye, one can see the semiquantitative analysis results. The naked eye detection limit of Met in tobacco is 25 μg/kg, and the detection threshold is 100 μg/kg. In addition, the cross-reactivity test shows that the mAb has good specificity for Met, and the GICA results have a good correlation with the indirect competitive enzyme-linked immunosorbent assay and liquid chromatography with tandem mass spectrometry test results, which show that the method is feasible and reliable and are more convenient and quicker than the methods using instrumentation for detection. Therefore, GICA may provide a useful tool for the rapid screening and detection of Met residues in tobacco.
研究领域:
农业化学
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分析化学
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植物科学
✓ 已验证
DOI
PubMed
高影响因子
Frontiers in Nutrition
·
2026
·
IF 5.5
Wei Sun,Yu Wang,Xin Zhang,Yifan Yue,Xiaoxuan Sun,Jiyan Miao,Shihang Han,Zhiqiang Zhou,Xiuguo Wang,Wentao Zhu
IntroductionThe extensive production of environmental pollutants has heightened susceptibility to intestinal disorders, potentially through alterations in the gut microbiota. However, the precise role of the gut microbiota in environmental pollutant-induced inflammation remains incompletely understood.MethodsIn this study, wild-type and IL-10−/− mice were employed to simulate the responses of healthy individuals and those genetically predisposed to inflammatory bowel disease (IBD) to environmental toxicants. Mice were exposed to metalaxyl, and an integrated multi-omics approach combining microbiome and metabolome profiling with machine learning was conducted to investigate the underlying mechanisms. Additionally, dietary tryptophan supplementation was administered to evaluate its protective effects.ResultsMetalaxyl exposure induced low-grade colonic inflammation in wild-type mice and triggered severe colitis in IBD-susceptible mice. Multi-omics analysis revealed that metalaxyl significantly disrupted gut microbial composition, reduced the synthesis of endogenous tryptophan-derived metabolites, and inhibited aryl hydrocarbon receptor (AhR) signaling, ultimately initiating intestinal barrier dysfunction and inflammatory cascades. Notably, dietary tryptophan restored gut tryptophan metabolite levels, strengthened AhR signaling, mitigated intestinal inflammation, and repaired barrier defects.DiscussionThis study identifies the gut microbiota as a central mediator of environmental pollutant-induced IBD and demonstrates that a high-tryptophan diet exerts beneficial effects against environmental colitis via the AhR axis. Furthermore, the stable phenotypes and high reproducibility of this dual-genotype mouse model underscore its utility as an ideal platform for investigating the enterotoxic effects of environmental pollutants.
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
·
IF 12.2
Xingkun Tang,Yunlong Meng,Haining Li,Kangyu Liu,Xinyao Wang,Zilin Zhong,Junsong Ye,Jianjun Chen
Metalaxyl is an acylanilide systemic fungicide that is widely applied and can readily enter ecosystems through leaching and soil runoff. This research utilized zebrafish as a model organism to thoroughly investigate the detrimental impacts of environmentally relevant levels of metalaxyl on the development of the notochord in zebrafish embryos and to elucidate the underlying molecular mechanisms through transcriptomics, pharmacological intervention and molecular biological detection. The preliminary results demonstrated that metalaxyl induced significant modifications in the developmental parameters of zebrafish embryos. This study has also assessed the long-term consequences of metalaxyl exposure during the embryonic development of zebrafish. This study have demonstrated that zebrafish exposed to metalaxyl exhibit a range of abnormalities, including defects in notochord vacuole biogenesis, somite segmentation disorders, anomalous notochord curvatures, craniofacial cartilage deformities, and irregular chordacentra mineralisation. Through transcriptomic and bioinformatics analysis, it was found that most of the genes exhibiting differential expression were linked to oxidative stress. Furthermore, the evidence indicated that oxidative stress was present, as demonstrated by increased malondialdehyde (MDA) production and a decrease in antioxidant enzyme activity (CAT, SOD, GSH). Interestingly, the developmental dysfunction induced by metalaxyl was partially rescued by chlorogenic acid. Overall, metalaxyl disrupts notochord and skeletal formation in zebrafish embryos by modulating oxidative stress mediated by reactive oxygen species.
研究领域:
环境科学
·
毒理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子