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Sheng Wu Gong Cheng Xue Bao = Chinese... Mar 2023Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high...
Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.
Topics: Rhodococcus; Phylogeny; Extracellular Polymeric Substance Matrix; Sewage; Biodegradation, Environmental; Pyridines
PubMed: 36994582
DOI: 10.13345/j.cjb.220822 -
Molecules (Basel, Switzerland) Aug 2021Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown... (Review)
Review
Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure-activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.
Topics: Azo Compounds; Imaging, Three-Dimensional; Phenols; Pyridines
PubMed: 34443460
DOI: 10.3390/molecules26164872 -
Biometals : An International Journal on... Feb 2021The emergence of resistant bacterial strains mainly due to misuse of antibiotics has seriously affected our ability to treat bacterial illness, and the development of...
The emergence of resistant bacterial strains mainly due to misuse of antibiotics has seriously affected our ability to treat bacterial illness, and the development of new classes of potent antimicrobial agents is desperately needed. In this study, we report the efficient synthesis of a new pyrazoline-pyridine containing ligand L1 which acts as an NN-donor for the formation of a novel silver (I) complex 2. The free ligand did not show antibacterial activity. High potency was exhibited by the complex against three Gram-negative bacteria, namely Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumanii with the minimum inhibitory concentration (MIC) ranging between 4 and 16 μg/mL (4.2-16.7 μM), and excellent activity against the fungi Candida albicans and Cryptococcus neoformans (MIC ≤ 0.25 μg/mL = 0.26 μM). Moreover, no hemolytic activity within the tested concentration range was observed. In addition to the planktonic growth inhibition, the biofilm formation of both Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa was significantly reduced by the complex at MIC concentrations in a dose-dependent manner for Pseudomonas aeruginosa, whereas a biphasic response was obtained for MRSA showing that the sub-MIC doses enhanced biofilm formation before its reduction at higher concentration. Finally, complex 2 exhibited strong DNA binding with a large drop in DNA viscosity indicating the absence of classical intercalation and suggesting the participation of the silver ion in DNA binding which may be related to its antibacterial activity. Taken together, the current results reveal that the pyrazoline-pyridine silver complexes are of high interest as novel antibacterial agents, justifying further in vitro and in vivo investigation.
Topics: Acinetobacter baumannii; Anti-Bacterial Agents; Biofilms; Coordination Complexes; Escherichia coli; Microbial Sensitivity Tests; Molecular Structure; Pseudomonas aeruginosa; Pyrazoles; Pyridines; Silver
PubMed: 33156436
DOI: 10.1007/s10534-020-00263-z -
International Journal of Nanomedicine 2019Aiming to produce pyridine azo disperse dyes with good fastness properties and promising antimicrobial activity, a number of novel systems of polyfunctionalized pyridine...
AIM
Aiming to produce pyridine azo disperse dyes with good fastness properties and promising antimicrobial activity, a number of novel systems of polyfunctionalized pyridine azo dyes and their selenium nanoparticles (SeNPs) were synthesized.
MATERIALS AND METHODS
The synthesized products were formed by the reaction of diazotized aniline derivatives or diazotized amino antipyrene with any of dibenzoyl methane or benzoyl acetone and cyanoacetamide in boiling ethanolic sodium ethoxide. The structures of the newly synthesized compounds were elucidated by elemental analysis and spectral data. Moreover, (SeNPs) of the pyridine azo disperse dyes were characterized by Ultra-Violet -Visible spectrophotometry, dynamic light scattering , X-ray diffraction, and transmission electron microscope analysis. On the other hand, the synthesized dyes and its (SeNPs) were applied for disperse dyeing of nylon 66 and their fastness properties were measured, such as washing, rubbing, perspiration, and light fastness. In addition, the antimicrobial activities for all the synthesized compounds and for (SeNPs) prepared compounds () were evaluated.
RESULTS
Compounds , and were the most active compounds against all Gram-positive and Gram-negative bacterial species. While, compounds , and were the most active toward some of the bacterial strains (at least two from the selected four strains). Moreover, compounds showed higher activity toward the fungal strain. Also, the minimal inhibitory concentrations for all the most active compounds were determined.
CONCLUSION
Finally, all the (SeNPs) compounds revealed higher activity against bacterial and fungal strains than the other synthesized compounds.
Topics: Anti-Bacterial Agents; Azo Compounds; Bacteria; Fungi; Metal Nanoparticles; Microbial Sensitivity Tests; Pyridines; Selenium; X-Ray Diffraction
PubMed: 31632007
DOI: 10.2147/IJN.S216914 -
Journal of the American Chemical Society Feb 2021Supramolecular catalysts emulate the mechanism of enzymes to achieve large rate accelerations and precise selectivity under mild and aqueous conditions. While...
Supramolecular catalysts emulate the mechanism of enzymes to achieve large rate accelerations and precise selectivity under mild and aqueous conditions. While significant strides have been made in the supramolecular host-promoted synthesis of small molecules, applications of this reactivity to chemoselective and site-selective modification of complex biomolecules remain virtually unexplored. We report here a supramolecular system where coencapsulation of pyridine-borane with a variety of molecules including enones, ketones, aldehydes, oximes, hydrazones, and imines effects efficient reductions under basic aqueous conditions. Upon subjecting unprotected lysine to the host-mediated reductive amination conditions, we observed excellent ε-selectivity, indicating that differential guest binding within the same molecule is possible without sacrificing reactivity. Inspired by the post-translational modification of complex biomolecules by enzymatic systems, we then applied this supramolecular reaction to the site-selective labeling of a single lysine residue in an 11-amino acid peptide chain and human insulin.
Topics: Boranes; Catalysis; Oxidation-Reduction; Pyridines
PubMed: 33471541
DOI: 10.1021/jacs.0c12479 -
Archiv Der Pharmazie May 2021Nine novel hydrazone derivatives (4a-i) incorporating pyridine and isatin moieties were synthesized through one-pot, four-component heterocyclic condensation reactions....
Nine novel hydrazone derivatives (4a-i) incorporating pyridine and isatin moieties were synthesized through one-pot, four-component heterocyclic condensation reactions. The structures of all new compounds (2a-e, 3a, 3c-e, and 4a-e) were identified by H nuclear magnetic resonance (NMR), C NMR, and Fourier-transform infrared spectroscopic techniques and elemental analysis. Cell viability assays for the tested hydrazone derivatives were performed and the log IC values of the compounds were calculated after a 24-h treatment. All hydrazide derivatives tested showed a promising antitumor activity against A-2780 cells as compared with the standard drug docetaxel with a log IC value of 0.2200 μM (p < .05). Seven of the examined compounds (4b-e, 4g-i) showed high cytotoxic activity against A-2780 cells as compared with the standard drug docetaxel. Whereas the log IC of docetaxel was 0.2200 μM for A-2780 cells at 24 h, the IC values of these compounds were -0.4987, -0.4044, -0.8138, -0.3868, -0.6954, -0.4751, and 0.1809 μM, respectively. Three of the compounds, 4b, 4d, and 4i, showed high cytotoxic activity against MCF-7 cells as compared with docetaxel (p < .05). Whereas the log IC of docetaxel was 0.2400 μM for MCF-7 cells at 24 h, the log IC values of compounds 4b, 4d, and 4i were -0.1293, -0.1700, and 0.2459 μM, respectively.
Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Hydrazones; Isatin; Molecular Structure; Pyridines; Structure-Activity Relationship
PubMed: 33368627
DOI: 10.1002/ardp.202000377 -
Current Medicinal Chemistry 2024Imidazo[4,5-b]pyridines are amongst the oldest known heteroaromatic derivatives. Their structural similarity with purine basis has however aroused the curiosity of... (Review)
Review
Imidazo[4,5-b]pyridines are amongst the oldest known heteroaromatic derivatives. Their structural similarity with purine basis has however aroused the curiosity of biologists and resulted in the developments of innovative bioactive compounds. This review thus firstly describes the main synthetic ways currently used to produce imidazo[ 4,5-b]pyridine derivatives, and secondly gives examples of their potential, especially focusing on protein inhibition abilities, thus opening the way to applications as anti-cancer or antimicrobial agents.
Topics: Humans; Anti-Infective Agents; Pyridines; Structure-Activity Relationship
PubMed: 37170991
DOI: 10.2174/0929867330666230426111650 -
Water Science and Technology : a... Apr 2024The sp. BN6-4 capable of degrading high concentrations of pyridine was isolated from the coking sludge. The removal rate of BN6-4 to 1,000 mg/L pyridine during 48 h was...
The sp. BN6-4 capable of degrading high concentrations of pyridine was isolated from the coking sludge. The removal rate of BN6-4 to 1,000 mg/L pyridine during 48 h was 97.49 ±1.59%. The primary intermediate metabolites of pyridine degradation by strain BN6-4 were identified by gas chromatography-mass spectrometry (GC-MS), including N-Ethylurea, acetamidoacetaldehyde, and N-Hydroxymethylacetamide, etc Subsequently, two different biodegradation pathways of pyridine were proposed. First, the hydroxylation of pyridine to form the intermediates pyridin-2(1H)-one and 5,6-dihydropyridine-2,5-diol, the former undergoing oxidative ring opening and the latter oxidative ring opening via N-C2 and C2-C3 ring opening to ammonia and carbon dioxide. Furthermore, the organic matter was greatly degraded by the bioremediation of real coking wastewater using BN6-4. This study enriched the microbial resource for pyridine degradation and provided new insights about the biodegradation pathway of pyridine, which is of great significance for the pyridine pollution control and coking wastewater treatment.
Topics: Pyridines; Biodegradation, Environmental; Water Pollutants, Chemical; Sewage
PubMed: 38678405
DOI: 10.2166/wst.2024.108 -
Bioorganic & Medicinal Chemistry Letters Nov 2020A novel series of 5H-chromeno[3,4-c]pyridine, 6H-isochromeno[3,4-c]pyridine and 6H-isochromeno[4,3-d]pyrimidine derivatives as dual ROCK1 and ROCK2 inhibitors is...
A novel series of 5H-chromeno[3,4-c]pyridine, 6H-isochromeno[3,4-c]pyridine and 6H-isochromeno[4,3-d]pyrimidine derivatives as dual ROCK1 and ROCK2 inhibitors is described. Optimization led to compounds with sub-nanomolar inhibitory affinity for both kinases and excellent kinome selectivity. Compound 19 exhibited ROCK1 and ROCK2 IC of 0.67 nM and 0.18 nM respectively.
Topics: Crystallography, X-Ray; Dose-Response Relationship, Drug; Humans; Models, Molecular; Molecular Structure; Protein Kinase Inhibitors; Pyridines; Structure-Activity Relationship; rho-Associated Kinases
PubMed: 32805407
DOI: 10.1016/j.bmcl.2020.127474 -
Natural Product Research Jun 2024In the present study, three series of 35 pyridine-based stilbenes include 10 new compounds prepared by Horner-Wadsworth-Emmons (HWE) reaction were assayed for cytotoxic...
In the present study, three series of 35 pyridine-based stilbenes include 10 new compounds prepared by Horner-Wadsworth-Emmons (HWE) reaction were assayed for cytotoxic activities toward two tumoral cell lines (K562 and MDA-MB-231) and one non-tumoral cell line (L-02). The bioassay results indicated that hybrid stilbenes formed at the C-3 position of pyridine displayed stronger antiproliferative activities against K562 cells and C-4 pyridine-based stilbenes showed broad-spectrum cytotoxic effects. Among them, C-3 pyridine-based stilbene bearing 2,6-dimethoxy possessed extremely potent antiproliferative activity with IC values 1.46 µM against K562 cells, along with excellent selectivity towards normal L-02 cells. In summary, the present study contributes to the development of natural stilbene-based derivatives as antitumor agents and may serve as a promising lead for the treatment of chronic myeloid leukemia (CML) worthy further investigation.
Topics: Stilbenes; Humans; Pyridines; Antineoplastic Agents; K562 Cells; Cell Line, Tumor; Cell Proliferation; Drug Design; Drug Screening Assays, Antitumor; Molecular Structure; Structure-Activity Relationship
PubMed: 37384584
DOI: 10.1080/14786419.2023.2227991