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1.
Food Chem ; 450: 138961, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38640544

RESUMO

The detection of tetracycline antibiotics (TCs) in food holds great significance in minimizing their absorption within the human body. Hence, this study aims to develop a rapid, convenient, real-time, and accurate detection method for detecting antibiotics in an authentic market setting. A colorimetric fluorescence sensor was devised for tetracycline detection utilizing PVA aerogels as the substrate. Its operating principle is based on the IFE effect and antenna effect. A detection device is designed to capture fluorescence images while deep learning was employed to aid in the detection process. The sensor exhibits high responsiveness with a mere 60-s requirement for detection and demonstrates substantial color changes(blue to red), achieving 99% accuracy within the range of 10-100 µM with the assistance of deep learning (Resnet18). Real sample simulation tests yielded recovery rates between 95% and 130%. Overall, the proposed strategy proved to be a simple, portable, reliable, and responsive solution for rapid real-time TCs detection in food samples.

2.
J Colloid Interface Sci ; 664: 53-62, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458055

RESUMO

As a progressive electronic energy storage device, the flexible supercapacitor holds tremendous promise for powering wearable/portable electronic products. Of various pseudocapacitor materials, vanadium dioxide (VO2) has garnered extensive attention due to its impressive theoretical capacitance. However, the challenges of inferior cycling life and lower energy density to be addressed. Herein, we prepare VO2 nanorods with winding carbon nanotubes (CNT) via a facile solvothermal route, followed by in situ polymerization of polyaniline (PANI) shell. Taking full advantage of the synergistic effect, the VO2/CNT@PANI composite delivers a high specific capacitance of 354.2F/g at 0.5 A/g and a long cycling life of âˆ¼ 88.2 % over 5000 cycles resulting from the enhanced conductivity of CNT and stabilization of PANI shell. By screen printing the formulated inks with outstanding rheological behaviours, we manufacture an in-planar VO2/CNT@PANI symmetric supercapacitor (VO2/CNT@PANI SSC) device featuring an orderly arrangement structure. This device yields a remarkable areal energy density of 99.57 µWh/cm2 at a power density of 387.5 µW/cm2 while retaining approximately âˆ¼ 87.6 % of its initial capacitance after prolonged use. Furthermore, we successfully powered a portable game machine for more than 2 min using two SSCs connected in series with ease. Therefore, this work presents a universal strategy that utilises combination and coating to boost electrochemical performance for flexible high-performance supercapacitors.

3.
J Agric Food Chem ; 72(5): 2512-2525, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38286814

RESUMO

As part of a program to discover novel succinate dehydrogenase inhibitor fungicides, a series of new pyrazole acyl(thio)urea compounds containing a diphenyl motif were designed and synthesized. Their structures were confirmed by 1H NMR, HRMS, and single X-ray crystal diffraction analysis. Most of these compounds possessed excellent activity against 10 fungal plant pathogens at 50 µg mL-1, especially against Rhizoctonia solani, Alternaria solani, Sclerotinia sclerotiorum, Botrytis cinerea, and Cercospora arachidicola. Interestingly, compounds 3-(difluoromethyl)-1-methyl-N-((3',4',5'-trifluoro-[1,1'-biphenyl]-2-yl)carbamoyl)-1H-pyrazole-4-carboxamide (9b, EC50 = 0.97 ± 0.18 µg mL-1), 1,3-dimethyl-N-((3',4',5'-trifluoro-[1,1'-biphenyl]-2-yl)carbamoyl)-1H-pyrazole-4-carboxamide (9a, EC50 = 2.63 ± 0.41 µg mL-1), and N-((4'-chloro-[1,1'-biphenyl]-2-yl)carbamoyl)-1,3-dimethyl-1H-pyrazole-4-carboxamide (9g, EC50 = 1.31 ± 0.15 µg mL-1) exhibited activities against S. sclerotiorum that were better than the commercial fungicide bixafen (EC50 = 9.15 ± 0.05 µg mL-1) and similar to the positive control fluxapyroxad (EC50 = 0.71 ± 0.11 µg mL-1). These compounds were not significantly phytotoxic to monocotyledonous and dicotyledonous plants. Structure-activity relationships (SAR) are discussed by substituent effects/molecular docking, and density functional theory analysis indicated that these compounds are succinate dehydrogenase inhibitors.


Assuntos
Compostos de Bifenilo , Fungicidas Industriais , Succinato Desidrogenase , Ureia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Fungicidas Industriais/química , Pirazóis/química , Antifúngicos/farmacologia
4.
Environ Sci Pollut Res Int ; 31(6): 9764-9783, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38194177

RESUMO

The development of effective and practical adsorbents for eliminating pollutants still remains a significant challenge. Herein, we synthesized a novel magnetically separable composite, Co0.6Fe2.4O4/MIL-101-NH2, through the in-situ growth of MIL-101-NH2 on magnetic nanoparticles, designed specifically for the removal of Congo red (CR) from aqueous solutions. MIL-101-NH2 possessed high BET surface area (240.485 m2•g-1) and facile magnetic separation function and can be swiftly separated (within 30 s) through an external magnetic field post-adsorption. The investigation systematically explored the influence of crucial parameters, including adsorbent dosage, pH, adsorption duration, temperature, and the presence of interfering ions, on CR adsorption performance. Findings indicate that CR adsorption adheres to the pseudo-second-order (PSO) kinetic model and the Langmuir isotherm model. Thermodynamic analysis reveals the spontaneity, endothermic nature, and orderly progression of the adsorption process. Remarkably, the adsorbent with 0.1 g•L-1 boasts an impressive maximum adsorption capacity of 1756.19 mg•g-1 for CR at 298.15 K, establishing its competitive advantage. The reuse of the adsorbent over 5 cycles remains 78% of the initial adsorption. The CR adsorption mechanisms were elucidated, emphasizing the roles of π-π interactions, electrostatic forces, hydrogen bonding, and metal coordination. Comparison with other dyes, such as methylene blue (MB) and methyl orange (MO), and exploration of adsorption performance in binary dye systems, demonstrates the superior capacity and selectivity of this adsorbent for CR. In conclusion, our magnetically separable metal-organic framework (MOF)based composite presents a versatile and effective solution for CR removal, with promising applications in water treatment and environmental remediation.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Vermelho Congo , Poluentes Químicos da Água/análise , Corantes , Adsorção , Cinética , Concentração de Íons de Hidrogênio
5.
Mol Cell Endocrinol ; 580: 112105, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37952726

RESUMO

Echinoderms are a phylum of invertebrate deuterostomes, which contain echinoids, asteroids, holothuroids, crinoids, and ophiuroids. Echinoderms have special evolutionary position and unique characteristics, including pentamerous radial body structure, elaborate calcareous endoskeletons, and versatile water vascular system. Echinoderms exhibit extraordinarily diverse reproductive modes: asexual reproduction, sexual reproduction, sexual reversal, etc. Endocrine regulation plays important well-known roles in sex differentiation, gonadal development and maturation, gametogenesis, and reproductive behavior in vertebrates. However, the entire picture of reproductive endocrinology in echinoderms as an evolutionary model of the closest marine invertebrate relatives to chordates has not been revealed. Here, we reviewed previous and recent research progress on reproductive endocrinology in echinoderms, mainly including two sections: Sex steroids in echinoderms and neuropeptide regulation in echinoderm reproduction. This review introduces a variety of endocrine regulatory mechanisms in reproductive biology of echinoderms. It discusses the vertebrate-like sex steroids, putative steroidogenic pathway and metabolism, and reproduction-related neuropeptides. The review will provide a deeper understanding about endocrine regulatory mechanisms of gonadal development in lower deuterostomes and the application of endocrine control in economic echinoderm species in aquaculture.


Assuntos
Cordados , Neuropeptídeos , Animais , Equinodermos , Evolução Biológica , Esteroides , Biologia
6.
Molecules ; 28(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37959782

RESUMO

Natural products are a main source of new chemical entities for use in drug and pesticide discovery. In order to discover lead compounds with high herbicidal activity, a series of new pyrido[2,3-d] pyrimidine derivatives were designed and synthesized using 2-chloronicotinic acid as the starting material. Their structures were characterized with 1H NMR, 13C NMR and HRMS, and the herbicidal activities against dicotyledonous lettuce (Lactuca sativa), field mustard (Brassica campestris), monocotyledonous bentgrass (Agrostis stolonifera) and wheat (Triticum aestivum) were determined. The results indicated that most of the pyrido[2,3-d] pyrimidine derivatives had no marked inhibitory effect on lettuce at 1 mM. However, most of the pyrido[2,3-d] pyrimidine derivatives possessed good activity against bentgrass at 1 mM. Among them, the most active compound, 3-methyl-1-(2,3,4-trifluorophenyl)pyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione (2o), was as active as the positive controls, the commercial herbicides clomazone and flumioxazin. Molecular simulation was performed with molecular docking and DFT calculations. The docking studies provided strong evidence that 2o acts as an herbicide by inhibition of protoporphyrinogen oxidase. However, the physiological results indicate that it does not act on this target in vivo, implying that it could be metabolically converted to a compound with a different molecular target.


Assuntos
Brassica , Herbicidas , Herbicidas/química , Simulação de Acoplamento Molecular , Pirimidinas/farmacologia , Pirimidinas/química , Brassica/metabolismo , Protoporfirinogênio Oxidase , Relação Estrutura-Atividade
7.
J Agric Food Chem ; 71(49): 19312-19323, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38018356

RESUMO

Developing environmentally friendly fungicides is crucial to tackle the issue of rising pesticide resistance. In this study, a series of novel pyrazole-4-carboxamide derivatives containing N-phenyl substituted amide fragments were designed and synthesized. The structures of target compounds were confirmed by 1H NMR, 13C NMR, and HRMS, and the crystal structure of the most active compound N-(1-(4-(4-(tert-butyl)benzamido)phenyl)propan-2-yl)-3-(difluoromethyl)-N-methoxy-1-methyl-1H-pyrazole-4-carboxamide (U22) was further determined by X-ray single-crystal diffraction. The bioassay results indicated that the 26 target compounds possessed good in vitro antifungal activity against Sclerotinia sclerotiorum with EC50 values for compounds U12, U13, U15, U16, U18, U22, and U23 being 4.17 ± 0.46, 8.04 ± 0.71, 7.01 ± 0.71, 12.77 ± 1.00, 8.11 ± 0.70, 0.94 ± 0.11, and 9.48 ± 0.83 µg·mL-1, respectively, which were the similar to controls bixafen (6.70 ± 0.47 µg·mL-1), fluxapyroxad (0.71 ± 0.14 µg·mL-1), and pydiflumetofen (0.06 ± 0.01 µg·mL-1). Furthermore, in vivo antifungal activity results against S. sclerotiorum indicated that compounds U12 (80.6%) and U22 (89.9%) possessed excellent preventative efficacy at 200 µg·mL-1, which was the same as the control pydiflumetofen (82.4%). Scanning electron microscopy and transmission electron microscopy studies found that the compound U22 could destroy the hyphal morphology and damage mitochondria, cell membranes, and vacuoles. The results of molecular docking of compound U22 and pydiflumetofen with succinate dehydrogenase (SDH) indicated they interact well with the active site of SDH. This study validated our approach and design strategy to produce compounds with an enhanced biological activity as compared to the parent structure.


Assuntos
Antifúngicos , Fungicidas Industriais , Antifúngicos/farmacologia , Antifúngicos/química , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo , Simulação de Acoplamento Molecular , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Pirazóis/farmacologia , Pirazóis/química
8.
J Agric Food Chem ; 71(40): 14458-14470, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782011

RESUMO

It is important to develop new insecticides with a new mode of action because of increasing pesticide resistance. In this study, a series of novel aryl isoxazoline derivatives containing the pyrazole-5-carboxamide motif were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR, and HRMS. Bioassays indicated that the 24 compounds synthesized possessed excellent insecticidal activity against Mythimna separate and no activity against Aphis craccivora and Tetranychus cinnabarinus. Among these aryl isoxazoline derivatives, 3-(5-(3,5-dichlorophenyl)-5-(trifluoromethyl)-4,5-dihydrozol-3-yl)-N-(4-fluorophenyl)-1-methyl-1H-pyrazole-5-carboxamide (IA-8) had the best insecticidal activity against M. separate, which is comparable with the positive control fluralaner. The molecular docking results of compound IA-8 and fluralaner with the GABA model demonstrated the same docking mode between compound IA-8 and positive control fluralaner in the active site of GABA. Molecular structure comparisons and ADMET analysis can potentially be used to design more active compounds. The structure-activity relationships are also discussed. This work provided an excellent insecticide for further optimization.


Assuntos
Inseticidas , Animais , Inseticidas/química , Simulação de Acoplamento Molecular , Desenho de Fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Ácido gama-Aminobutírico
9.
Chem Commun (Camb) ; 59(70): 10540-10543, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37566103

RESUMO

A facile protocol for the preparation of indole-isoindole derivatives was developed and proceeds via a palladium-catalyzed [3+2] cyclization of isocyanides with alkynyl imines. In this transformation, the palladium catalyst has a triple role, serving simultaneously as a π acid, a transition-metal catalyst and a hydride ion donor, thus enabling the dual function of isocyanide both as a C1 synthon for cyanation and a C1N1 synthon for imidoylation. Significantly, the reaction is the sole successful example for accessing indole-isoindole derivatives, and will open up new avenues to assemble unique N-heterocycle frameworks. Furthermore, the synthetic value of this protocol is demonstrated in the late-stage modification of physiologically active molecules and in the construction of aggregation-induced emission compounds.

10.
Discov Med ; 35(176): 275-282, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37272094

RESUMO

BACKGROUND: Asiaticoside is one of the main components of triterpenoid saponins extracted from Centella asiatica. Asiaticoside has shown the effects of wound healing, osteoclastogenesis, anti-inflammatory, anti-cancer, and improving cognition in multiple human disease models. However, studies on the antifatigue effects of asiaticoside have not been explored. Therefore, the aim of this study was to investigate the potential antifatigue effect and underlying mechanism of asiaticoside administration on exhaustive exercise performance. METHODS: Male Kunming mice were divided into four groups randomly (n = 20/group). Saline (10 mL/kg) was administered to the model control group and the other three experimental groups were fed with low (10 mg/kg), medium (20 mg/kg) and high (40 mg/kg) asiaticoside once/daily for 14 days. The antifatigue effect of asiaticoside on mice was estimated by analyzing changes in body weight, weight-loaded swimming time, rotating time, lactic acid, urea nitrogen, liver/muscle glycogen, serumal superoxide dismutase, superoxide dismutase and the liver tissues of hematoxylin and eosin (H&E) staining. RESULTS: The results indicated that no significant differences were observed in the body weight of each group (p > 0.05). Compared with the model control group, supplementation of asiaticoside significantly prolonged the weight-loaded swimming time and rotating time; Decreased the blood lactic acid (LA), blood urea nitrogen (BUN), and serumal malonaldehyde (MDA); And increased the content of liver/muscle glycogen and serumal superoxide dismutase levels (SOD) (p < 0.05). Furthermore, the pathological results of the liver were improved greatly. The maximal effect was observed in the medium group of 20 mg/kg. CONCLUSIONS: Asiaticoside is capable of reducing the fatigue effect by regulating energy consumption, energy metabolism and improving antioxidant activity after exercise. While there are still some shortcomings in this study, our findings provide a scientific basis for developing an asiaticoside-based antifatigue supplement.


Assuntos
Estresse Oxidativo , Triterpenos , Animais , Masculino , Camundongos , Peso Corporal , Glicogênio/metabolismo , Ácido Láctico , Superóxido Dismutase/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico
11.
Molecules ; 28(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37110607

RESUMO

A series of new fluorinated quinoline analogs were synthesized using Tebufloquin as the lead compound, 2-fluoroaniline, ethyl 2-methylacetoacetate, and substituted benzoic acid as raw materials. Their structures were confirmed by 1H NMR, 13C NMR, and HRMS. The compound 8-fluoro-2,3-dimethylquinolin-4-yl 4-(tert-butyl)benzoate (2b) was further determined by X-ray single-crystal diffraction. The antifungal activity was tested at 50 µg/mL, and the bioassay results showed that these quinoline derivatives had good antifungal activity. Among them, compounds 2b, 2e, 2f, 2k, and 2n exhibited good activity (>80%) against S. sclerotiorum, and compound 2g displayed good activity (80.8%) against R. solani.


Assuntos
Antifúngicos , Quinolinas , Antifúngicos/química , Espectroscopia de Ressonância Magnética , Quinolinas/farmacologia , Relação Estrutura-Atividade
12.
Talanta ; 252: 123881, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055076

RESUMO

This work aims to develop the novel TVB-N sensitive film for monitoring food freshness. The film was fabricated based on carboxymethyl starch sodium (CMS)/agar (AG) complex and natural pigment, red radish anthocyanins (RRA). However, RRA is highly unstable under high humid conditions for their hydrophily. To immobilize RRA in AG film, we brought up CMS (negative charge) to immobilize RRA (positive charge) via electrostatic attractions and combined CMS and AG via hydrogen bond self-assembly. Zeta potential, Fourier transforms infrared (FT-IR) spectra, and X-ray diffraction analysis proved the electrostatic interaction and hydrogen bond self-assembly effect, indicating RRA immobilized effectively. Migration evaluation displayed that RRA remained stable in a high humidity environment (from RH 35%-95%). And its color difference is less than 5% in the low-temperature environment (4 °C). The prepared sensing film was found to be applied to detect the freshness of packaged grass carp and shrimp products. Its colors changed from initial orange-red to light red (3rd day) and then purple (4th day) with the increase of volatile amines inside the packaging. These findings suggested the film can be used as a sensing device for intelligent packaging of protein-rich food.


Assuntos
Antocianinas , Embalagem de Alimentos , Antocianinas/química , Ligação de Hidrogênio , Eletricidade Estática , Espectroscopia de Infravermelho com Transformada de Fourier , Sódio , Ágar , Concentração de Íons de Hidrogênio
13.
Pestic Biochem Physiol ; 188: 105228, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36464348

RESUMO

A new series of cyclopropane-1,1-dicarboxylic (CPD) acid analogues were designed and synthesized. CPD is an inhibitor of ketol-acid reductoisomerase (KARI), an enzyme of the branched chain amino acid pathway in plants. The structures of CPD analogues were characterized by 1H NMR and HRMS. The structure of N,N'-bis(4-(tert-butyl)phenyl)cyclopropane-1,1-dicarboxamide was further elucidated by X-ray diffraction. The herbicidal activities of these compounds were tested against lettuce (Lactuca sativa) and bentgrass (Agrostis stolonifera). Most of these compounds exhibited low herbicidal activity against both plant species. Among them, N,N'-bis(2-ethylphenyl)cyclopropane-1,1-dicarboxamide displayed moderate activity against bentgrass. Inhibition of KARI activity by the CPD analogues was also assessed experimentally and by molecular docking simulation with results supporting inhibition of KARI as their mode of action. These results provide the basis for design of more effective KARI inhibitors.


Assuntos
Herbicidas , Herbicidas/farmacologia , Simulação de Acoplamento Molecular , Ácidos Dicarboxílicos/farmacologia , Ciclopropanos/farmacologia
14.
Front Oncol ; 12: 965773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176388

RESUMO

Objective: To illustrate the knowledge hotspots and cutting-edge research trends of 18F-FDG PET/CT radiomics, the knowledge structure of was systematically explored and the visualization map was analyzed. Methods: Studies related to 18F-FDG PET/CT radiomics from 2013 to 2021 were identified and selected from the Web of Science Core Collection (WoSCC) using retrieval formula based on an interview. Bibliometric methods are mainly performed by CiteSpace 5.8.R3, which we use to build knowledge structures including publications, collaborative and co-cited studies, burst analysis, and so on. The performance and relevance of countries, institutions, authors, and journals were measured by knowledge maps. The research foci were analyzed through research of keywords, as well as literature co-citation analysis. Predicting trends of 18F-FDG PET/CT radiomics in this field utilizes a citation burst detection method. Results: Through a systematic literature search, 457 articles, which were mainly published in the United States (120 articles) and China (83 articles), were finally included in this study for analysis. Memorial Sloan-Kettering Cancer Center and Southern Medical University are the most productive institutions, both with a frequency of 17. 18F-FDG PET/CT radiomics-related literature was frequently published with high citation in European Journal of Nuclear Medicine and Molecular Imaging (IF9.236, 2020), Frontiers in Oncology (IF6.244, 2020), and Cancers (IF6.639, 2020). Further cluster profile of keywords and literature revealed that the research hotspots were primarily concentrated in the fields of image, textural feature, and positron emission tomography, and the hot research disease is a malignant tumor. Document co-citation analysis suggested that many scholars have a co-citation relationship in studies related to imaging biomarkers, texture analysis, and immunotherapy simultaneously. Burst detection suggests that adenocarcinoma studies are frontiers in 18F-FDG PET/CT radiomics, and the landmark literature put emphasis on the reproducibility of 18F-FDG PET/CT radiomics features. Conclusion: First, this bibliometric study provides a new perspective on 18F-FDG PET/CT radiomics research, especially for clinicians and researchers providing scientific quantitative analysis to measure the performance and correlation of countries, institutions, authors, and journals. Above all, there will be a continuing growth in the number of publications and citations in the field of 18F-FDG PET/CT. Second, the international research frontiers lie in applying 18F-FDG PET/CT radiomics to oncology research. Furthermore, new insights for researchers in future studies will be adenocarcinoma-related analyses. Moreover, our findings also offer suggestions for scholars to give attention to maintaining the reproducibility of 18F-FDG PET/CT radiomics features.

15.
Nanomaterials (Basel) ; 12(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35808052

RESUMO

Although it is one of the promising candidates for pseudocapacitance materials, Ni(OH)2 is confronted with poor specific capacitance and inferior cycling stability. The design and construction of three-dimensional (3D) nanosphere structures turns out to be a valid strategy to combat these disadvantages and has attracted tremendous attention. In this paper, a 3D α-Ni(OH)2 nanosphere is prepared via a facile and template-free dynamic refluxing approach. Significantly, the α-Ni(OH)2 nanosphere possesses a high specific surface area (119.4 m2/g) and an abundant porous structure. In addition, the as-obtained α-Ni(OH)2 electrodes are investigated by electrochemical measurements, which exhibit a high specific capacitance of 1243 F/g at 1 A/g in 6 M KOH electrolyte and an acceptable capacitive retention of 40.0% after 1500 charge/discharge cycles at 10 A/g, which can be attributed to the sphere's unique nanostructure. Furthermore, the as-assembled Ni(OH)2-36//AC asymmetric supercapacitor (ASC) yields a remarkable energy density of 26.50 Wh/kg, with a power density of 0.82 kW/kg. Notably, two ASCs in series can light a 2.5 V red lamp sustainably for more than 60 min, as well as power an LED band with a rated power of 25 W. Hence, this 3D α-Ni(OH)2 nanosphere may raise great potential applications for next-generation energy storage devices.

16.
J Agric Food Chem ; 70(14): 4303-4315, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35357135

RESUMO

Thirty novel dioxolane ring compounds were designed and synthesized. Their chemical structures were confirmed by 1H NMR, HRMS, and single crystal X-ray diffraction analysis. Bioassays indicated that these dioxolane ring derivatives exhibited excellent fungicidal activity against Rhizoctonia solani, Pyricularia oryae, Botrytis cinerea, Colletotrichum gloeosporioides, Fusarium oxysporum, Physalospora piricola, Cercospora arachidicola and herbicidal activity against lettuce (Lactuca sativa), bentgrass (Agrostis stolonifera), and duckweed (Lemna pausicostata). Among these compounds, 1-((2-(4-chlorophenyl)-5-methyl-1,3-dioxan-2-yl)methyl)-1H-1,2,4-triazole (D17), 1-(((4R)-2-(4-chlorophenyl)-4-methyl-1,3-dioxolan-2-yl)methyl)-1H-1,2,4-triazole (D20), 1-((5-methyl-2-(4-(trifluoromethyl)phenyl)-1,3-dioxan-2-yl)methyl)-1H-1,2,4-triazole (D22), and 1-((2-(4-fluorophenyl)-1,3-dioxolan-2-yl)methyl)-1H-1,2,4-triazole (D26) had broad spectrum fungicidal and herbicidal activity. The IC50 values against duckweed were 20.5 ± 9.0, 14.2 ± 6.7, 24.0 ± 11.0, 8.7 ± 3.5, and 8.0 ± 3.1 µM for D17, D20, D22, and D26 and the positive control difenoconazole, respectively. The EC50 values were 7.31 ± 0.67, 9.74 ± 0.83, 17.32 ± 1.23, 11.96 ± 0.98, and 8.93 ± 0.91 mg/L for D17, D20, D22, and D26 and the positive control difenoconazole against the plant pathogen R. solani, respectively. Germination experiments with Arabidopsis seeds indicated that the target of these dioxolane ring compounds in plants is brassinosteroid biosynthesis. Molecular simulation docking results of compound D26 and difenoconazole with fungal CYP51 P450 confirmed that they both inhibit this enzyme involved in ergosterol biosynthesis. The structure-activity relationships (SAR) are discussed by substituent effect, molecular docking, and density functional theory analysis, which provided useful information for designing more active compounds.


Assuntos
Ascomicetos , Fungicidas Industriais , Dioxolanos , Ergosterol , Fungicidas Industriais/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
17.
J Sci Food Agric ; 102(11): 4589-4598, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35170048

RESUMO

BACKGROUND: A shelf-life that is too short is the main problem with strawberries. Nano-TiO2 can catalyze and oxidize ethylene under ultraviolet (UV) light irradiation to eliminate its ripening effect on fruits and prolong the freshness period. RESULTS: In this work, nano-TiO2 modified by methacryloxy propyl trimethoxyl silane (KH570) was blended with low-density polyethylene (LDPE) to prepare modified atmosphere packaging (MAP), and the influence of TiO2 content on films was analyzed before and after UV treatment. The results show that the modified nano-TiO2 (M-TiO2 ) can be uniformly distributed in LDPE, improving its mechanical strength, hydrophobicity, oxygen barrier and UV shielding properties. A modified atmosphere with low ethylene, low O2 and high CO2 can be created to inhibit the ripening and spoilage of strawberries. The weight loss rate of fruit can be effectively reduced. The tendency of fruit firmness decline and nutrient loss can be slowed and stabilized, contributing to controllable shelf-life. Excellent freshness preservation function can be realized without special UV treatment. CONCLUSION: Since UV treatment is rare in actual storage and transportation, LDPE/M-TiO2 composite film has practical value as MAP for strawberry and similar non-climacteric fruits. © 2022 Society of Chemical Industry.


Assuntos
Fragaria , Atmosfera , Etilenos/análise , Fragaria/química , Frutas/química , Oxigênio/análise , Polietileno
18.
Dalton Trans ; 51(8): 3137-3145, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35112674

RESUMO

In the context of the ever-increasing energy crisis, electrocatalytic water splitting has attracted widespread attention as an effective means to provide clean energy. However, the oxygen evolution reaction (OER), which is an important anodic half reaction, shows very slow kinetics due to the multi-step electron transfer process, which severely restricts the efficiency of energy conversion. Herein, we used a simple solvothermal method to dope iron into the cobalt-containing hydroxide precursor, and successfully prepared the Fe-doped Co-oxide electrocatalyst Co3-xFexO4-0.01. It only needs an overpotential of 294 mV to perform the OER at a current density of 10 mA cm-2, and has a low Tafel slope of 47.3 mV dec-1. Moreover, Co3-xFexO4-0.01 has excellent stability. There is no significant increase in the overpotential for oxygen evolution at a current density of 10 mA cm-2 after nearly 20 h. BET surface area test and XPS spectroscopy results show that Fe doping provides more mesopores and oxygen bridges, which is conducive to the construction of active sites and electronic regulation during the OER. This work can help design more bimetallic based highly active OER materials.

19.
Molecules ; 28(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615249

RESUMO

Natural products are a source for pesticide or drug discovery. In order to discover lead compounds with high fungicidal or herbicidal activity, new niacinamide derivatives derived from the natural product niacinamide, containing chiral flexible chains, were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR and HRMS analysis. The fungicidal and herbicidal activities of these compounds were tested. The fungicidal activity results demonstrated that the compound (S)-2-(2-chloronicotinamido)propyl-2-methylbenzoate (3i) exhibited good fungicidal activity (92.3% inhibition) against the plant pathogen Botryosphaeria berengriana at 50 µg/mL and with an EC50 of 6.68 ± 0.72 µg/mL, which is the same as the positive control (fluxapyroxad). Compound 3i was not phytotoxic and could therefore be used as a fungicide on crops. Structure-activity relationships (SAR) were studied by molecular docking simulations with the succinate dehydrogenase of the fungal mitochondrial respiratory chain.


Assuntos
Fungicidas Industriais , Herbicidas , Praguicidas , Praguicidas/farmacologia , Niacinamida/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Fungicidas Industriais/química , Herbicidas/farmacologia , Estrutura Molecular
20.
Food Chem ; 373(Pt B): 131434, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34731803

RESUMO

Colorimetric sensing is a low-cost, intuitive method for monitoring the freshness of food. We prepared a colorimetric strip sensor array by mixing different amounts of bromophenol blue (BPB) and bromocresol green (BCG). As results of NH3 simulation, the array strip turned from yellow to blue, and the number of blue spots increased with the increasing NH3, like a progress bar. Although the actual color is quite different, the color-changing trend was consistent with the simulated model calculated by a computer. The progress bar results remained stable under three lighting conditions. Furthermore, in the Cod preservation experiment, the color-changing progress of the strip sensor array is consistent with the simulation and can indicate Cod freshness while providing more distinguish levels. Therefore, a "progress bar" indicator built by this strategy possess the potential of realizing nondestructive, more accurate, and commercially available food quality monitoring through the naked eye and smart equipment recognition.


Assuntos
Colorimetria , Qualidade dos Alimentos
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