查找使用阿拉丁产品的科研文献

Resistance Mechanism to Metsulfuron-Methyl in Polypogon fugax

Xiaoyue Yu,Hanwen Wu,Jianping Zhang,Yongjie Yang,Wei Tang,Yongliang Lu

Polypogon fugaxis a common winter weed in China and other Asia countries. We have previously found aP. fugaxbiotype (R) resistant to acetyl co-enzyme A carboxylase (ACCase) herbicides also cannot be effectively controlled by some acetolactate synthase (ALS) herbicides. This study evaluated the level of resistance to four ALS herbicides (metsulfuron-methyl, chlorsulfuron, monosulfuron, pyribambenz isopropyl) in the R biotype and the associated resistance mechanism. The R biotype exhibited moderate level of resistance to metsulfuron-methyl (6.0-fold) compared with the sensitive biotype (S). Sequence analysis ofALSgene revealed that twoALSgenes existed inP. fugax. However, no substitution associated with ALS resistance mechanism were found inALSgenes between the S and R biotypes. The activity of ALS enzyme isolated from the R biotype was inherently higher and less sensitive to metsulfuron-methyl than the S biotype. Glutathione S-transferases (GST) activity was also less sensitive to metsulfuron-methyl in the R than as the S biotypes. Malathion, a cytochrome P450 (CYP) monooxygenase inhibitor, had much greater synergistic effect with metsulfuron-methyl on the R than as the S plants, reducing the ED50value (herbicide dose to inhibit growth by 50%) of metsulfuron-methyl by 23- and 6-fold, respectively, suggesting that CYP mediated enhanced metabolism might contribute to the resistance to ALS herbicides. These results suggest that metsulfuron-methyl resistance in the R biotype was associated with the up-regulated ALS enzymatic activity and the GST and CYP-mediated enhanced herbicide metabolism.Keywords:metsulfuron-methyl;ALS enzyme activity;Polypogon fugax;glutathione S-transferases;cytochrome P450

Visual and Colorimetric Sensing of Metsulfuron-Methyl by Exploiting Hydrogen Bond-Induced Anti-Aggregation of Gold Nanoparticles in the Presence of Melamine

Guangyang Liu,Ruonan Zhang,Xiaodong Huang,Lingyun Li,Naixin Liu,Jing Wang,Donghui Xu

Various highly sensitive and selective analytical methods have been used to monitor metsulfuron-methyl residue in the environment. However, these methods involve costly instruments and complex, time-consuming operations performed in laboratories. Here, a rapid, convenient, and sensitive colorimetric sensor based on anti-aggregation of gold nanoparticles (AuNPs) is demonstrated for the rapid detection of metsulfuron-methyl in agricultural irrigation water. The AuNPs could be induced to aggregate in the presence of melamine and exhibited a distinct color change from wine-red to blue. The aggregation was suppressed by a strong hydrogen-bonding interaction between metsulfuron-methyl and melamine. The differences of the absorbance at 523 nm (ΔA523) and the color change was linearly related to metsulfuron-methyl concentration over the range 0.1–100 mg/L, as observed visually and by UV-vis (Ultraviolet-visible) spectrometry. The detection limit of the sensor was as low as 0.05 mg/L (signal/noise = 3), and was used to determine metsulfuron-methyl in spiked water and in agricultural irrigation water samples. Recoveries were in the range of 71.2–100.4%, suggesting that the colorimetric sensor was suitable for the determination of metsulfuron-methyl in agricultural water samples.Keywords:colorimetric sensor;gold nanoparticle;anti-aggregation;metsulfuron-methyl;melamine;agricultural irrigation water

Enhancing the efficiency of polypyrrole-dodecylbenzene sulfonic acid in-tube solid-phase microextraction coating for analysis of nitrogen-containing pesticides in water environments

Ma Rong,Yu Shuangshuang,Li Yafang,Lin Yan,Ma Xiaodong

Background: With the growing use of nitrogen-containing pesticides in agriculture, their residues in the environment have raised significant public health concerns.Objective: This study aimed to develop a novel PPy-DBSA/IT-SPME coating to enhance the detection efficiency of polar nitrogen-containing pesticides in water matrices.Methods: The preparation conditions were optimized, including pyrrole concentration at 7.0 mol/L, DBSA concentration at 0.014 mol/L, oxidant concentration at 0.35 mol/L, and a coating cycle repeated 10 times. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed for detection.Results: The novel coating effectively adsorbed 19 different categories of polar nitrogen-containing pesticides, including sulfonylureas, triazolopyrimidines, diphenyl ether herbicides, benzoylurea insecticides, and phenylurea herbicides, with unadsorbed rates below 10%. The analytical method achieved an average recovery rate of 61.92% to 115.21%, with an RSD below 5.0%. Detection and quantification limits ranged from 0.012 to 0.524 μg/L and 0.127 to 5.243 μg/L, respectively.Conclusion: The developed method is green, efficient, simple, and cost-effective. It offers an environmentally friendly and user-friendly approach for the detection of polar nitrogen-containing pesticide residues, demonstrating good recovery and precision. This method holds potential for wide application in environmental monitoring and food safety.

Spatiotemporal distribution and potential ecological risks of current-use pesticides (CUPs) in Laizhou Bay, China

Yufei Dai,Xianli Song,Jing Zhao,Limin Wang,Xiaoru Cui,Li Lu,Jingyu Zhang,Haoyu Zhang,Dahai Zhang,Keqiang Li

Pesticides occur widely in coastal waters and potentially pose a risk to marine ecosystems and human health. The spatiotemporal distribution of current-use pesticides (CUPs) was studied in Laizhou Bay (LZB) and the Xiaoqing River watershed in China during the summer of 2022 and spring of 2023. The pesticide composite index ( PCI ) and persistence index ( PI ) were established in association with the risk quotient ( RQ ) to assess the ecological risk in LZB. In this study, 17 and 12 kinds of CUP were detected in rivers and LZB seawater, respectively, with atrazine and neonicotinoid insecticides (NEOs) being the most frequently detected CUPs at higher concentrations. The average concentration of CUPs decreased from rivers to the coast and towards the center of the LZB, with higher levels in spring and lower levels in summer in rivers and a reversed pattern in seawater. The high-risk areas lie in the LZB coastal area and the estuary. Atrazine, chlorpyrifos, and imidacloprid might pose a high risk to aquatic organisms based on the RQ in the LZB, whereas the priority concern pesticides are atrazine and triazophos based on the PCI and PI . This study is of great significance for assessing the composite ecological risk of CUPs in aquatic environments.

Taxonomic structure and functional assembly of the broad-spectrum sulfonylurea herbicide-degrading microbial consortium L1 under different herbicide substrates

Xiang Li,Yumeng Dai,Xinyu Guan,Zhiyang Han,Xu Li,Xiujuan Wang,Zhencheng Su,Huiwen Zhang,Mingkai Xu

The overuse of sulfonylurea herbicides (SUHs) in agricultural environments has resulted in severe residues that damage ecosystems and harm human health. In this study, we described a microbial consortium L1, capable of broad-spectrum degradation of SUHs, which degraded 200   mg   L -1 of bensulfuron-methyl, chlorimuron-ethyl, metsulfuron-methyl, tribenuron-methyl and thifensulfuron-methyl by 81.27%, 97.59%, 62.34%, 72.06% and 100%, respectively, within 7 days. The 16S rDNA and metagenome sequencing results showed that the dominant genera in consortium L1 under different SUHs were concentrated in Methyloversatilis , Pseudoxanthomonas and Chitinophaga . However, the diversity and structure of consortium L1 varied significantly under different SUHs, reflecting differences in both abundant and rare taxa, which could also interconvert. KEGG annotations showed that consortium L1 had the same functional composition when degrading different SUHs, but the number of gene annotations was significantly different, with benzoate degradation (ko00362) being the most enriched of all treatments. Furthermore, the results showed that functional redundancy existed in degradation high contribution genera, with abundant taxa having a greater impact on the degradation of different SUHs. Additionally, network analysis revealed that both rare and abundant genera had more positive edges, suggesting that the strains engaged in more mutualistic or symbiotic cooperation during the degradation process. More importantly, rare taxa play an important role in connectivity between modules. Overall, the assembly of abundant and rare taxa communities and functional composition were closely related to broad-spectrum consortium degrading. These findings deepen the understanding of bacterial consortia and provide valuable insights to enhance their potential in environmental remediation.

Colloidal gold-based lateral flow immunoassay for detecting cyclosulfamuron residues in cereal samples

Lu Zeng,Huan Lv,Xiangrui Li,Wenjia Yang,Wencan Luo,Linghong Kong,Qiujin Zhu

Cyclosulfamuron (CS) is a widely used sulfonylurea herbicide in plant cultivation and food production, and poses significant threats to ecological balance and food safety. To address this concern, we designed a novel CS hapten using computer-simulated semi-antigens. A monoclonal antibody (mAb) exhibiting high specificity and affinity was generated, with an affinity constant of 1.049×10 9 L/mol and a semi-inhibitory concentration (IC 50 ) of 4.94 ng/mL. Leveraging this anti-CS mAb, we constructed a rapid, visually detectable, quantitative lateral flow immunoassay (LFIA) to detect CS in cereals. Under the optimal conditions, the cut-off values were determined to be 100 μg/kg for brown rice and corn samples and 50 μg/kg for rice samples. The corresponding limits of detection values (LODs) were found to be 1.93 μg/kg in brown rice, 2.18 μg/kg in corn and 1.93 μg/kg in rice, respectively. The recovery rates ranged from 96.2% to 104.8% with coefficients of variation ranging from 3.5% to 6.4%, showing good agreement with the results obtained by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The proposed assay demonstrated robust analytical performance, with significant application potential for rapid, on-site detection.

A multi-colloidal gold immunochromatography assay for rapid and simultaneous detection of 13 herbicides

Lu Qianqian,Xu Xinxin,Qu Aihua,Liu Liqiang,Li Yuzhe,Sun Maozhong,Xu Chuanlai,Kuang Hua

Herbicide residues in agricultural products can have adverse effects on the environment and human health, therefore, there is an urgent need to establish a sensitive, rapid, and wide-ranging detection method. In this study, haptens of phenylurea herbicides (PUs) and sulfonylurea herbicides (SUs) were analyzed and designed based on computational simulation techniques, and two high-performance broad-spectrum monoclonal antibodies against PUs and SUs were prepared. On this basis, a multi-colloidal gold immunochromatography assay (multi-CGIA) was developed to simultaneously detect 13 herbicides in wheat. The visual limit of detection (vLOD) for PUs including diuron, chlortoluron, neburon, chlorbromuron, and linuron was 1–2 µg/kg. The vLOD for SUs including metsulfuron methyl, ethametsulfuron-methyl, sulfometuron-methyl, tribenuron methyl, cinosulfuron, triasulfuron, chlorimuron-ethyl, and chlorsulfuron was 2–10 µg/kg. The results of real sample determination indicated that the multi-CGIA is accurate, stable, and reliable, and adaptable to on-site preliminary screening of actual samples.

A Magnetic Molecularly Imprinted Electrochemical Sensor with Selective and Sensitive Detection Ability towards Methotrexate in Serum Samples

Shukai Sun,Shun Li,Zhixiang Sun,Yue Zhai,Chao Xuan,Yusun Zhou,Xiaomin Yang,Qingwu Tian,Tingting Zhou

A highly selective and sensitive method for detecting methotrexate (MTX) in serum samples using a molecularly imprinted electrochemical sensor have been developed. The preparation of the magnetic molecularly imprinted polymers (MIPs) employed MTX as the template, which was synthesized via sol-gel technology. These polymers were then integrated with carbon paste to create the MMIPs/CPE (MMPE) sensor. Under optimized conditions, the MMPE sensor exhibited outstanding selectivity and sensitivity for MTX detection, with two linear ranges of 0.01-0.5 and 0.5-20.0 μM, and a detection limit of just 1.63 nM. Furthermore, the sensor's practical application in serum sample analysis demonstrated its efficacy, with recovery rates between 81.0% and 125.0%. This innovation holds promise for clinical diagnosis and therapeutic applications, facilitating accurate and specific MTX detection in serum samples.

Analysis of sulfonylurea herbicides in grain samples using molecularly imprinted polymers on the surface of magnetic carbon nanotubes by extraction coupled with HPLC

Xiaoxiao You,Ligang Chen

A new strategy for the isolation and enrichment of sulfonylurea herbicides in grain samples was obtained by using magnetic molecularly imprinted polymers (MMIPs) using carbon nanotubes as the matrix, nicosulfuron as the template molecule, 3-aminopropyltriethoxysilane as the functional monomer, tetraethyl orthosilicate as the cross-linker and cetyl trimethylammonium bromide as the dispersant. The characteristics of the MMIPs were assessed by transmission electron microscopy, vibrating sample magnetometry, X-ray diffractometry, elemental analysis, the Brunauer–Emmett–Teller method and Fourier transform infrared spectroscopy. The binding characteristics of the imprinted materials were researched using isothermal adsorption experiments, kinetics adsorption experiments and selectivity experiments. The recoveries of four sulfonylurea herbicides were more than 80.0% and the detection limits were 0.0107, 0.0151, 0.0147 and 0.0123 μg g−1, respectively. RSDs of intra-day and inter-day precisions in the range of 0.7–2.4% and 5.3–8.4% were obtained, respectively. The results demonstrate that MMIPs are promising for the preconcentration, purification and analysis of sulfonylurea herbicides in grain samples.

Ionic liquid-based dispersive liquid–liquid microextraction followed by dispersive solid phase extraction coupled with HPLC-DAD for the determination of sulfonylurea herbicides in soymilk samples

Jilong Li,Weili Xu,Xiujuan Wang,Fengze Wu,Lin Wang,Ji Feng,Zhibing Wang,Hanqi Zhang