Engineering of Ultra-Thin Layer of MIL-125(Ti) Nanosheet\Zn-Tetracarboxy-Phthalocyanine S-Scheme Heterojunction as Photocatalytic CO2 Reduction Catalyst.

Metal-organic frameworks (MOFs) with ultrathin 2D structure have attracted remarkable attention in photocatalytic application owing to the accessibility of abundant active sites on the surface. But high charge recombination results in poor photocatalytic activity. Herein, the synthesis of ultrathin MIL-125(Ti) nanosheets is reported with a thickness of 1.3 nm through a simple chemical reaction route of precursor solution aging and subsequent solvothermal process for photocatalytic CO2 production. The maximal CO evolution rate achieves 200.8 µmol g-1 h-1, which is prominently higher than that (78.6 µmol g-1 h-1) of the bulk MIL-125(Ti) counterpart. Furthermore, the structurally stable Zn (II) tetracarboxy phthalocyanine (ZnTcPc) molecules assembly on ultrathin MIL-125(Ti) nanosheet (NS) to form MIL-125(Ti) NS\ZnTcPc S-scheme heterojunction through the strong interaction between the Ti3+ in MIL-125(Ti) and the COOH in ZnTcPc. The introduction of ZnTcPc greatly extends light absorption range and increases charge separation rate. The experimental and density functional theory calculation results validate that the MIL-125(Ti) NS\ZnTcPc S-scheme heterojunction can favor CO2 adsorption and effectively depress the formation energy of the intermediates, achieving a high CO evolution rate of 450.8 µmol g-1 h-1. This work provides a strategy of engineering 2D MOF-based heterostructure systems for photocatalytic application.

Targeting SARS-CoV-2 proteins: In Silico Investigation with Polypyridyl-based Zn(II)-Curcumin Complexes.

Herein, we have selected eight Zn(II)-based complexes viz., [Zn(bpy)(acac)Cl] (1), [Zn(phen)(acac)Cl] (2), [Zn(dppz)(acac)Cl] (3), [Zn(dppn)(acac)Cl] (4), [Zn(bpy)(cur)Cl] (5), [Zn(phen)(cur)Cl] (6), [Zn(dppz)(cur)Cl] (7), [Zn(dppn)(cur)Cl] (8), where bpy=2,2'-bipyridine, phen=1,10-phenanthroline, dppz=benzo[i]dipyrido[3,2-a:2',3'-c]phenazine, dppn=naphtho[2,3-i]dipyrido[3,2-a:2',3'-c]phenazine, acac=acetylacetonate, cur=curcumin and performed in silico molecular docking studies with the viral proteins, i.e., spike protein (S), Angiotensin-converting enzyme II Receptor protein (ACE2), nucleocapsid protein (N), main protease protein (Mpro), and RNA-dependent RNA polymerase protein (RdRp) of SARS-CoV-2. The binding energy calculations, visualization of the docking orientation, and analysis of the interactions revealed that these complexes could be potential inhibitors of the viral proteins. Among complexes 1-8, complex 6 showed the strongest binding affinity with S and ACE2 proteins. 4 exerted better binding affinity in the case of the N protein, whereas 8 presented the highest binding affinities with Mpro and RdRp among all the complexes. Overall, the study indicated that Zn(II) complexes have the potential as alternative and viable therapeutic solutions for COVID-19.

A trinuclear Zn (II) schiff base dicyanamide complex attenuates bacterial biofilm formation by ROS generation and membrane damage and exhibits anticancer activity.

A trinuclear Zn (II) complex, [(ZnL{N(CN)2})2Zn], termed complex 1 has been synthesized by the reaction of an aqueous solution of sodium dicyanamide to the methanolic solution of Zn (CH3COO)2, 2H2O and corresponding Schiff base (H2L) which is derived from 1:2 condensation of 1, 4 butane diamine with 3-ethoxy salicylaldehyde. Complex 1 is characterized by elemental analysis, IR, UV and Single X-ray diffraction study. Drug resistance is a growing global public health concern that has prompted researchers to look into advanced alternative treatment modalities. In this context, complex 1 has shown promising antibacterial and antibiofilm efficacy against gram-positive Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus strains. Complex 1 attenuated Staphylococcal biofilm formation by reducing several virulence factors including the formation of extracellular polysaccharide matrix, slime, haemolysin, staphyloxanthin, auto-aggregation, cell surface hydrophobicity, and motility. Notably, complex 1 mechanistically potentiated Reactive Oxygen Species (ROS) generation within the bacterial cells, leading to the damage of bacterial cell membrane followed by DNA leakage and thereby impeding the growth of Staphylococcus aureus. Furthermore, complex 1 significantly exhibited anticancer activity by reducing the growth of prostate adenocarcinoma cells. It obstructed the migration of cancer cells by potentiating apoptosis and arresting the cell cycle at the G2/M phase. In summary, complex 1 could act as a potent candidate for the generation of novel antibacterial, antibiofilm as well as anticancer treatment regimens for the management of drug-resistant biofilm-mediated Staphylococcus aureus infection and lethal prostate malignancy.

Label-Free Detection of Unbound Bilirubin and Nitrophenol Explosives in Water by a Mechanosynthesized Dual Functional Zinc Complex: Recognition of Picric Acid in Various Common Organic Media.

High levels of unconjugated bilirubin (UB) in serum lead to asymptomatic and neonatal jaundice and brain dysfunctions. Herein, we have reported the detection of UB at as low as 1 µM in an aqueous alkaline medium using a Zn(II) complex. The specificity of the complex has been validated by the HPLC in the concentration window 6-90 µM, which is rare. The sensory response of the probe at physiological pH against nitro explosives developed it as an instant-acting fluorosensor for picric acid (PA) and 2,4-dinitrophenol (2,4-DNP). Spectroscopic titration provided a binding constant of 4×105  M-1 with PA. The naked eye detection was found to be 15 µM. The solid-state photoluminescent nature of the complex enabled it for PA sensing in the solid phase. Interestingly, the probe remained fluorescent in various volatile and non-volatile organic solvents. As a result, it can also detect PA and 2,4-DNP in a wide range of common organic media. NMR studies revealed the coordination of PA, 2,4-DNP, and UB to the Zn(II) center of the probe, which is responsible for the observed quenching of the probe with the analytes.

Synthesis of Novel [{(2-Amino-5-Nitro-N-[(E)-Thiophen-2-yl-Methylidene]Aniline-κ3N1:N4:S)(Sulphato-κ2O1:O3)}Zinc(II)] Complex with Physico-Chemical and Biological Perspective Exploration: A Combined Experimental and Computational Studies.

A novel metal complex was synthesized using freshly prepared 2-Amino-5-nitro-N-[(E)-thiophen-2-yl-methylidene]aniline ligand with Zn (II) sulphate heptahydrate in a 1:1 molar ratio. The ligand and the complex were characterized using different spectroscopic techniques, and the complex was assigned a distorted square pyramidal geometry. Additionally, DNA binding assays and antibacterial activity were used to assess the biological perspectives for the synthesized complex, including the ligand and complex which was further confirmed by molecular docking. Fluorescence Spectroscopy, viscosity measurement, and adsorption measurement were used to investigate the interaction of the Zn (II) complex with CT-DNA. A comparative in vitro antibacterial activity study against Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, and Staphylococcus aureus strains were studied with free ligand and Zn (II) metal complex. The stable geometry of the complex was additionally established through computational simulation utilizing density functional theory, which was followed by the calculation of several electronic properties. The ADMET characteristics of the complex and ligand were also assessed using ADMET analysis. The in-silico ADMET properties pointed to a significant drug-likeness feature in the synthesized compounds, based on the Lipinski criteria.

Synthesis and Characterization of Zn(II) Complex of 4-chloro-2-(((2-phenoxyphenyl)imino)methyl)phenol and its Biological Efficacies: DNA Interaction, ADMET, DFT and Molecular Docking Study.

Condensing 2-phenoxyaniline with 5-chlorosalicyldehyde under reflux conditions, a 4-chloro-2-(((2-phenoxyphenyl)imino)methyl)phenol Schiff base has been Synthesized. A zinc complex was synthesized by combining the ligand in a 1:1 molar ratio with zinc sulphateheptahydrate. Mass spectroscopy, NMR, infrared, and elemental analysis were used to characterize the ligand and zinc complex. By measuring the molar conductance, the non-electrolytic character of the complex was confirmed. The zinc ion is coordinated in a pentadentate manner, according to an IR and NMR investigation. Viscosity measurements, absorption and fluorescence spectroscopy were utilized to examine the complex's interaction with CT (calf thymus) DNA. Furthermore, the ligand and complex's ADMET characteristics were ascertained through the use of ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) study. Calculation of the different electronic parameters of the optimized structure through Density Functional Theory (DFT) indicated the stability of the Zn(II) complex. Molecular docking study reflected the future opportunity for the consideration of Zn(II) complex to fight against Alzheimer and Glaucoma diseases.

Vitamin B6 Cofactor Pyridoxal 5'-phosphate Conjugated Papain-Stabilized Fluorescent Gold Nanoclusters for Switch-on Detection of Zinc(II).

In this study, fluorescent gold nanoclusters (AuNCs) conjugated with pyridoxal-5-phosphate (PLP) were synthesized, characterized, and used for Zn2+ fluorescence turn-on sensing. PLP was conjugated over the surface of papain-stabilized fluorescent gold nanoclusters (pap-AuNCs; λex = 380 nm, λem = 670 nm) by forming imine linkage. Due to this modification, the red color emitting pap-AuNCs changed to orange color emitting nanoclusters PLP_pap-AuNCs. The nano-assembly PLP_pap-AuNCs detect Zn2+ selectively by showing a notable fluorescence enhancement at 477 nm. Zn2+ detection with PLP_pap-AuNCs was quick and easy, with an estimated detection limit of 0.14 µM. Further, paper strips and cotton buds coated with PLP_pap-AuNCs were developed for affordable on-site visual detection of Zn2+. Finally, the detection of Zn2+ in actual environmental water samples served as validation of the usefulness of PLP_pap-AuNCs.

Highly Selective Ratiometric Sensors for Pb2+ Based on Luminescent Zn(II)-Coordination Polymers with Thiophenedicarboxylate. Crystal Structures and Spectroscopic Studies.

The development of luminescent coordination polymers for the selective sensing of Pb2+ in water constitutes an active area of research that impacts analytical, environmental, and inorganic chemistry. Herein, two novel water-stable 2D Zn-coordination polymers {[Zn2(H2O)2(tdc)2(bpy)]·(H2O)}n 1 and [Zn(tdc)(tmb)]n 2 (tdc = thiophenedicarboxylate; bpy = 4,4'-bipyridine and tmb = 4,4'-trimethylenebipyridine) were synthesized, structurally determined by single crystal X-ray diffraction, and studied in-depth as luminescent sensors for a series of cations (Ca2+, Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ Cd2+, Hg2+ and Pb2+) in 20% aqueous ethanol. These Zn-polymers possess photostability in 20% aqueous ethanol with a strong emission at 410 upon excitation at 330 nm and quantum yields of around Φ = 0.09. Under these conditions, Pb+2 can be efficiently sensed with polymer 2 through a fluorescent ratiometric response with selectivity over common interfering metal ions such as Cu2+, Cd2+ and Hg2+ in the micromolar concentration range (detection limit = 1.78 ± 10 µM). Such selectivity/affinity of Pb2+ over Hg2+ for luminescent chemosensors is still rare. On the basis of spectroscopic tools (1H NMR, far ATR-IR, PXRD), the X-ray crystal structure of 2, and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopic analysis, the ratiometric fluorescent response is proposed via an efficient metal-ion exchange driven through interactions between thiophenedicarboxylate rings and Pb2+ ions. The use of flexible luminescent Zn-coordination polymers as sensors for selective and direct detection of Pb2+ in aqueous media has been unexplored until now.

Highly efficient recovery of Zn (II) from zinc-containing wastewater by tourmaline tailings geopolymers to in-situ construct nanoscale ZnS for the photodegradation of tetracycline hydrochloride.

While treating zinc-containing wastewater, recovering zinc for reuse as a secondary resource has significant environmental and economic benefits. Herein, based on the alkali-activated tourmaline tailings geopolymers (TTG) after adsorption of zinc ions (Zn (II)), a series of new composites with in-situ construction ZnS nanoparticles on TTG (ZnS/TTG) were synthesized, and used as photocatalysts for the photodegradation of tetracycline hydrochloride (TCH) in solution. Specifically, ZnS nanoparticles were uniformly and stably distributed in the layered structure of TTG, interweaving with each other to generate an interfacial electric field, which could induce more photocarrier generation. Meanwhile, TTG acted as an electron acceptor to accelerate the electron transfer at the interface, thus enhancing the photodegradation activity for TCH. The active radical quenching experiments combined with the ESR indicated that the active species produced during the photocatalytic degradation of TCH by ZnS/TTG composites were •O2- and photogenerated h+. When the initial concentration of Zn (II) was 60 mg/L, the synthesized 60-ZnS/TTG composites (0.5 g/L) reached 91.53% degradation efficiency of TCH (10 mg/L) at pH = 6. Furthermore, the possible pathways and mechanism of 60-ZnS/TTG composites photodegraded TCH were revealed with the aid of degraded intermediates. This report not only proposed valuable references for reusing heavy metal ions and removing TCH from wastewater, but also provided promising ideas for realizing the conversion of used adsorbents into high-efficiency photocatalysts.

Characterization of Copper(II) and Zinc(II) Complexes of Peptides Mimicking the CuZnSOD Enzyme.

Antimicrobial peptides are short cationic peptides that are present on biological surfaces susceptible to infection, and they play an important role in innate immunity. These peptides, like other compounds with antimicrobial activity, often have significant superoxide dismutase (SOD) activity. One direction of our research is the characterization of peptides modeling the CuZnSOD enzyme and the determination of their biological activity, and these results may contribute to the development of novel antimicrobial peptides. In the framework of this research, we have synthesized 10, 15, and 16-membered model peptides containing the amino acid sequence corresponding to the Cu(II) and Zn(II) binding sites of the CuZnSOD enzyme, namely the Zn(II)-binding HVGD sequence (80-83. fragments), the Cu(II)-binding sequence HVH (fragments 46-48), and the histidine (His63), which links the two metal ions as an imidazolate bridge: Ac-FHVHEGPHFN-NH2 (L1(10)), Ac-FHVHAGPHFNGGHVG-NH2 (L2(15)), and Ac-FHVHEGPHFNGGHVGD-NH2 (L3(16)). pH-potentiometric, UV-Vis-, and CD-spectroscopy studies of the Cu(II), Zn(II), and Cu(II)-Zn(II) mixed complexes of these peptides were performed, and the SOD activity of the complexes was determined. The binding sites preferred by Cu(II) and Zn(II) were identified by means of CD-spectroscopy. From the results obtained for these systems, it can be concluded that in equimolar solution, the -(NGG)HVGD- sequence of the peptides is the preferred binding site for copper(II) ion. However, in the presence of both metal ions, according to the native enzyme, the -HVGD- sequence offers the main binding site for Zn(II), while the majority of Cu(II) binds to the -FHVH- sequence. Based on the SOD activity assays, complexes of the 15- and 16-membered peptide have a significant SOD activity. Although this activity is smaller than that of the native CuZnSOD enzyme, the complexes showed better performance in the degradation of superoxide anion than other SOD mimics. Thus, the incorporation of specific amino acid sequences mimicking the CuZnSOD enzyme increases the efficiency of model systems in the catalytic decomposition of superoxide anion.

Deciphering the evolution of metallo-ß-lactamases: A journey from the test tube to the bacterial periplasm.

Understanding the evolution of metallo-ß-lactamases (MBLs) is fundamental to deciphering the mechanistic basis of resistance to carbapenems in pathogenic and opportunistic bacteria. Presently, these MBL-producing pathogens are linked to high rates of morbidity and mortality worldwide. However, the study of the biochemical and biophysical features of MBLs in vitro provides an incomplete picture of their evolutionary potential, since this limited and artificial environment disregards the physiological context where evolution and selection take place. Herein, we describe recent efforts aimed to address the evolutionary traits acquired by different clinical variants of MBLs in conditions mimicking their native environment (the bacterial periplasm) and considering whether they are soluble or membrane-bound proteins. This includes addressing the metal content of MBLs within the cell under zinc starvation conditions and the context provided by different bacterial hosts that result in particular resistance phenotypes. Our analysis highlights recent progress bridging the gap between in vitro and in-cell studies.

Construction of RNA silencing system of Penicillium brevicompactum and genetic manipulation of the regulator pbpcz in mycophenolic acid production.

Penicillium brevicompactum is a critical industrial strain for the production of mycophenolic acid (MPA). However, the genetic background of Penicillium brevicompactum is unclear, and there are few tools available for genetic manipulation. To investigate its gene function, we first verified the feasibility of a pair of citrate synthase promoter (Pcit) and terminator (Tcit) from P. brevicompactum by constructing a fluorescent expression cassette. Based on this, an RNAi vector was designed and constructed with reverse promoters. This study focused on the functional investigation of the pbpcz gene in P. brevicompactum, a regulator belonging to the Zn(II)2Cys6 family. RNAi was used to silence the pbpcz gene, providing a valuable tool for genetic studies in P. brevicompactum. After seven days, we observed differences in the number of spores between different phenotypes strains of pbpcz gene. Compared to the wild-type strain (WT), the spore yield of the pbpcz gene silencing mutant (M2) was only 51.4 %, while that of the pbpcz gene overexpressed mutant (SE4) was increased by 50 %. Expression levels of the three genes (brlA, abaA, and wetA) comprising conidia's central regulatory pathway were significantly reduced in the pbpcz gene silencing mutant, while fluorescence localization showed that PbPCZ protein was mainly distributed in spores. The results indicated that the pbpcz gene is critical for conidia and asexual development of P. brevicompactum. In addition, overexpressing the pbpcz gene resulted in a 30.3 % increase in MPA production compared to the wild type, with a final yield of 3.57 g/L. These results provide evidence that PbPCZ acts as a positive regulator in P. brevicompactum, controlling MPA production and regulating conidia and asexual development.

Zinc binding of a Cys2His2-type zinc finger protein is enhanced by the interaction with DNA.

Zinc finger proteins specifically recognize DNA sequences and, therefore, play a crucial role in living organisms. In this study the Zn(II)-, and DNA-binding of 1MEY#, an artificial zinc finger protein consisting of three finger units was characterized by multiple methods. Fluorimetric, circular dichroism and isothermal calorimetric titrations were applied to determine the accurate stability constant of a zinc finger protein. Assuming that all three zinc finger subunits behave identically, the obtained thermodynamic data for the Zn(II) binding were ΔHbinding site = - (23.5 - 28.0) kcal/mol (depending on the applied protonation state of the cysteines) and logß'pH 7.4 = 12.2 ± 0.1, being similar to those of the CP1 consensus zinc finger peptide. The specific DNA binding of the protein can be characterized by logß'pH 7.4 = 8.20 ± 0.08, which is comparable to the affinity of the natural zinc finger proteins (Sp1, WT1, TFIIIA) toward DNA. This value is ~ 1.9 logß' unit higher than those determined for semi- or nonspecific DNA binding. Competitive circular dichroism and electrophoretic mobility shift measurements revealed that the conditional stability constant characteristic for Zn(II) binding of 1MEY# protein increased by 3.4 orders of magnitude in the presence of its target DNA sequence.

Zn(II) Coordination Polymer: Luminescence Sensing for Fe3+ Ion and Used as Metal Gel Particles Against Lung Cancer.

Presented here is a new Zn(II) coordination polymer, namely [Zn2(L)2(bpe)]n (1, H2L = 4-({2-[(4-carboxyphenoxy)methyl]phenyl}methoxy)benzoic acid, bpe = 1,2-bis(4-pyridinyl)ethane), which has been hydrothermally synthesized via the mixed-ligand strategy. Moreover, compound 1 emits intense luminescence at room temperature, and can be used as a luminescent sensor for the detection of Fe3+ in water solution with high selectivity and sensitivity. As representatives of natural polysaccharides, hyaluronic acid (HA) and carboxymethyl chitosan (CMCS) have good biocompatibility. A new type of HA/CMCS gel particles loaded with Paclitaxel drug metal-organic framework was prepared by chemical synthesis method and its micromorphology was studied. Finally, biological experiments were conducted to evaluate the new system's effect on the activity of human lung cancer cells.

Benzil Bis-Hydrazone Based Fluorescence 'Turn-on' Sensor for Highly Sensitive and Selective Detection of Zn(II) Ions.

In this study, a novel Benzil Bis-Hydrazone (BBH) sensor with two C = N-N = C moieties was designed and synthesized based on the condensation reaction between benzil-dihydrazone (b) and cinnamaldehyde. The BBH probe in dimethylsulfoxide showed extremely weak fluorescence. However, the same solution exhibited an intensive fluorescence enhancement (152-fold) with the introduction of Zn(II) ions. In contrast, no or negligible fluorescence changes were observed when other ions were added. The fluorogenic behavior of BBH towards the examined cations indicated an excellent selectivity of the BBH sensor for Zn(II) cations without any interference from other cations like Fe(II), Mg(II), Cu(II), Co(II), Mn(II), Cr(III), Hg(II), Sn(II), Al(I), La(III), Ca(II), Ba(II), Na(I), K(I), and especially Cd(II). Moreover, the UV-vis spectrophotometric titrations revealed that a 1:1 stoichiometric complex BBH-Zn(II) was formed during the Zn(II) sensing and the binding constant value for this complex was calculated to be equal to 106.8. Further, in order to show the affinity of the BBH sensor for Zn(II) cations, it was deemed necessary to determine the limit of detection (LOD) which was found to equal to 2.5 10-4 M.

A New Zn(II) Compound: Luminescent Property and Promoting Knee Cartilage Repair by Modulating Iron Death.

The hydrothermal reactions of bis{6-{5-methyl-1 H,7 H-[1,2,4]triazolo[1,5-a]pyrimidin-7-one}}methane (L) and Zn(NO3)2·6H2O at 180 ℃ afforded a novel Zn(II) coordination polymer (CP), that is, {[Zn2(L)(µ2-O)2]·3H2O}n (1), which further characterized via Single crystal X-ray diffraction (SCXRD), elemental analysis (EA), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA). Besides, this CP reveals strong luminescence that may be caused by the charge transfer within the ligand. In biological study, the new compound was evaluated for its protective effect on chondrocytes. This compound significantly up-regulated GPX4 and down-regulated HO-1 mRNA levels, thereby inhibiting iron death in chondrocytes.

Synthesis of Cu (II) and Zn (II) Complexes of a Quinoline Based Flexible Amide Receptor as Fluorescent Probe for Dihydrogen Phosphate and Hydrogen Sulphate and Their Antibacterial Activity.

A novel 8-hydroxy quinoline-derived amide receptor, in conjunction with its Cu (II) and Zn (II) complexes, has been strategically developed to function as remarkably efficient fluorescent receptors with a distinct capability for anion sensing. The comprehensive characterization of the synthesized compounds were achieved through UV-Vis, IR, NMR, and HRMS spectroscopic techniques. Among the Cu (II) and Zn (II) complexes, the latter exhibits superior selectivity for anions, specifically dihydrogen phosphate and hydrogen sulfate, as their tetrabutylammonium salts in a 9:1 acetonitrile-water (v/v) mixture. The Cu (II) complex demonstrates enhanced anion binding compared to the amide ligand, albeit with reduced selectivity. Furthermore, the affinity was evaluated using the Benesi-Hildebrand plot. The binding constants and Limit of Detection (LOD) for both complexes were precisely quantified. The Job plot illustrates a clear 1:1 binding interaction between the metal complexes and the guest anions. Significantly, both metal-complex receptors display a broad spectrum of antibacterial activity, against both gram-positive and gram-negative bacteria. It is worth highlighting that the Zn (II) complexed receptor outperforms the Cu (II) complexed receptor, as evidenced by its considerably lower Minimum Inhibitory Concentration (MIC) value against both bacterial strains.

Synergistic analysis of performance, functional genes, and microbial community assembly in SNDPR process under Zn(II) stress.

One of the most prevalent heavy metals found in rural sewage is Zn(II), while its effect on simultaneous nitrification, denitrification and phosphorus removal (SNDPR) remains unclear. In this work, the responses of SNDPR performance to long-term Zn(II) stress were investigated in a cross-flow honeycomb bionic carrier biofilm system. The results indicated that Zn(II) stress at 1 and 5 mg L-1 could increase nitrogen removal. Maximum ammonia nitrogen, total nitrogen, and phosphorus removal efficiencies of up to 88.54%, 83.19%, and 83.65% were obtained at Zn(II) concentration of 5 mg L-1. The functional genes, such as archaeal amoA, bacterial amoA, NarG, NirS, NapA, and NirK, also reached the highest value at 5 mg L-1 Zn(II), with the absolute abundances of 7.73 × 105, 1.57 × 106, 6.68 × 108, 1.05 × 109, 1.79 × 108, and 2.09 × 108 copies·g-1 dry weight, respectively. The neutral community model demonstrated that deterministic selection was responsible for the system's microbial community assembly. Additionally, response regimes with extracellular polymeric substances and cooperation among microorganisms facilitated the stability of the reactor effluent. Overall, the findings of this paper contribute to improving the efficiency of wastewater treatment.

Design anticancer potential of Zn(II)isoleucinedithiocarbamate complex on MCF-7 cell lines: synthesis, characterization, molecular docking, molecular dynamic, ADMET, and in-vitro studies.

Cisplatin is a cancer medication widely used today, but it still poses some problems due to its toxic properties in the body. To overcome this issue, a new complex has been developed as a potential anticancer drug prospect by minimizing its toxic consequences. A novel Zn(II)IleDTC complex containing isoleucine dithiocarbamate ligands has been produced and analyzed using a range of analytical and spectroscopic methods. The Zn(II) IleDTC complex were characterized using various methods, including UV-Vis spectroscopy, FT-IR, determination of melting point, conductivity, and HOMO-LUMO analysis. Furthermore, computational NMR spectrum analysis was conducted in this study. Molecular docking studies was conducted to evaluate the potential of Zn(II) isoleucine dithiocarbamate as an HIF1 inhibitor. The results showed that the Zn complex exhibited a good docking score of -6.6 and formed hydrogen bonds with ARG 17, VAL264, and GLU15, alkyl bonds with TRP27 and LEU32, and Pi-Alkyl bonds with PRO41 and ARG44. This suggests that the Zn(II) isoleucine dithiocarbamate complex could be a promising candidate for cancer treatment with potential HIF1 inhibition properties. To assess the dynamic stability and efficacy of protein-ligand interactions over time, molecular dynamics simulations was conducted for both individual proteins and protein complexes. The cytotoxicity evaluation of Zn(II) isoleucine dithiocarbamate against MCF-7 cells obtained an IC50 value of 362.70 µg/mL indicating moderate cytotoxicity and morphological changes of cancer cells causing cancer cells to undergo apoptosis. The Zn(II) isoleucine dithiocarbamate complex may have promising potential as an anticancer compound due to its significant inhibitory effect on the breast cancer cell line (MCF7). According to the ADMET study, the complex exhibits drug-like characteristics with low toxicity, further supporting its potential as a viable drug candidate.

A zinc (II) complex comprising an aminoethyl-nitropyridine-derived N,N,O-donor Schiff base ligand serves as an efficient ON-OFF probe for Cu(II).

A new fluorescent zinc (II) complex-based probe 1 encompassing a Schiff's base (E)-2-methoxy-6-((2-[5-nitropyridin-2-ylamino]ethylimino)methyl)phenol (HL) was designed, synthesized, and used for the highly selective detection of Cu2+ . Ligand HL and complex 1 were characterized using various spectroscopic techniques such as 1 H, 13 C-NMR, and FTIR spectroscopy, high-resolution mass spectronomy (HRMS), UV/visible light spectroscopy, and fluorescence studies. Ligand HL did not exhibit any considerable change in fluorescence in the presence of various cations. Notably, its Zn(II) complex 1 exhibited highly selective 'TURN-OFF' fluorescence signalling towards Cu2+ that remained uninterrupted with competing analytes. Probe 1 interacted with Cu2+ in 1:2 (1:Cu2+ ) stoichiometry as estimated through a Job's plot. Moreover, the selectivity of 1 was further confirmed through the interaction of the 1 + Cu2+ complex with some possible interfering metal ions inducing an insignificant response. Additionally, the association and quenching constant were determined to be 3.30 × 104 M-1 and 0.21 × 105 M-1 through the Benesi-Hildebrand method and Stern-Volmer plot, respectively.