Antibacterial Studies Research Articles

Ag induced plasmonic TiO2 for photocatalytic degradation of pharmaceutical under visible light: Insights into mechanism, antimicrobial and cytotoxicity studies

Global concerns include water scarcity and shortage, which are escalated by organic pollutants such as naproxen (NPX) that deteriorate drinking water and taint access to safe drinking water by humans. Moreover, NPX may cause gastrointestinal difficulties, cardiovascular risks, kidney damage, allergic reactions, liver toxicity, bleeding issues and pregnancy risks, hence it is essential to remove it in water. Ag-TiO2 was synthesized by hydrothermal method for NPX degradation. Ag on TiO2 reduced the band gap and surface area of TiO2 and resulted in a plasmonic Ag-TiO2 composite of 0.2 % Ag. The photocatalytic degradation of 0.2 % Ag-TiO2 was 80 % in 180 minutes using a solar simulator during NPX degradation with a first order reaction rate that was 3.6 times faster than that of pure TiO2 and the catalyst showed good stability for four cycles. The dual activity of Ag0 surface plasmon resonance improved light absorption capability and enhanced charge transfer for increased photodegradation rate and stability. The antibacterial studies demonstrated that 0.2 % Ag-TiO2 posted strong antibacterial properties under light irradiation and less in the dark, with a greater effect on gram-negative than gram-positive bacteria. The minimum inhibitory concentration (MIC) values of 620, 1250, 2500, 2500 µg/mL were attained against B. subtilis, S. aureus, E. coli and S. typhimurium bacteria, respectively. The low cell toxicity of 0.2 % Ag-TiO2 was determined using human embryonic kidney (HEK293) cells with an inhibitory concentration (IC50) of 61.09 ± 0.24 µg/mL under light irradiation. Radical trapping experiments demonstrated that hydroxyl radicals (OH•) played a vital role during the degradation and bactericidal activity of NPX under light irradiation. This work advances new insights on the synthesis of less toxic nanoparticles with high photocatalytic and bactericidal activity for possible applications at industrial scale.

In vitro assessment of corrosion, antibacterial properties, and degradation behavior of zirconia-coated polyetheretherketone (PEEK)

The medical industry often uses ceramic and polymeric coatings to safeguard metal substrates. However, more investigation is required to explore the implementation of ceramic coatings on polymer substrates and to determine their degradation and in vitro characteristics. This work involves applying zirconia coating onto the 3D-printed PEEK polymer substrate using the RF magnetron sputtering technique. With varying layer thickness and printing speed parameters, PEEK samples (S1, S2, S3, and S4) were 3D printed and coated with zirconia. The coated and uncoated samples were immersed in Fusayama artificial saliva solution for 30 days. Following immersion in artificial saliva, this study examined the corrosion of 3D-printed PEEK samples with and without coatings. Elemental mapping, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy were employed to evaluate sample morphology and estimate the binding energy of possible compounds generated in the artificial saliva solution. In vitro assessments such as antibacterial studies were performed against E. coli and S. aureus, and cytotoxic analysis was performed using Human Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) to determine cell proliferation. The results indicated that sample S3, printed with 0.15 mm layer thickness and 20 mm/s print speed coated with zirconia showed a better degradation rate of 9.01% whereas the other three samples S1, S2, and S4 coated with zirconia showed deterioration rates of 36.4%, 33% and 16% respectively. Sample S3 showed a better antibacterial activity as biofilm formation was absent and also showed cell viability of about 79% and hence can be considered as a viable option for dental applications.

Exploring Structural and Optical Properties of Nanoparticles of Barium Titanate and Iron doped Barium Titanate and Their Potential Application in Antibacterial Activity

Background: Barium Titanate (BaTiO3) is a good candidate for a variety of applications due to its excellent dielectric, ferroelectric and piezoelectric properties. Methods: Pure and doped Barium Titanate (BTO) nanoparticles have been synthesized by the sol-gel method. Barium hydroxide octahydrate (Ba (OH)2.8H2O) and titanium (IV) iso-propoxide (Ti {OCH[CH3]2}4) were used as starting materials. Apart from pure Barium Titanate nanoparticles, Fe-doped BaTiO3 nanoparticles of three different concentrations: 0.1, 0.2 and 0.3 in mol% were prepared and characterized using X-ray diffraction (XRD), UV visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR). Results: From the X-ray diffraction pattern, the particle size was found to be varied in a range of 17-25nm. By using UV visible spectroscopy it was observed that the band gap energy of pure BaTiO3 NP is 3.2eV. As the pure BaTiO3 nanoparticles are doped with 0.1% Fe, the band gap reduces to 3.175eV. For BaTiO3 doped with 0.2% and 0.3% Fe, the band gap energy values are 2.709 and 2.652 respectively. FTIR spectra were used to analyze the vibrational modes of BaTiO3. From the result obtained from FTIR, we can see that the absorption spectrum ranges from 450cm-1-4000cm-1. The prominent peak of pure BaTiO3 is at 500cm-1 which is due to the vibration of the Ti-O band in crystal lattice. For BaTiO3 doped with Fe2O3, the wave number of the absorption peak is shifted from 500cm-1 in pure BaTiO3. The antibacterial studies were conducted on Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. Conclusion: Both pure and iron-doped Barium Titanate showed significant antibacterial properties, confirming the antibacterial property of Barium Titanate nanoparticles.

Phyto-mediated fabrication of cerium oxide nanoparticles using Mollugo oppositifolia L aqueous leaf extract: Antibacterial, antitonicity, and molecular docking studies

The use of bio-processes for synthesizing metal oxide nanoparticles represents a forefront area of research in nanotechnology. This study introduces a rapid and eco-friendly approach for producing cerium oxide nanoparticles (CeO2 NPs) utilizing the aqueous extract of Mollugo oppositifolia L leaves as a catalyst. The synthesized CeO2 NPs underwent comprehensive characterization through scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and Fourier transform infrared spectroscopy (FT-IR). Furthermore, the antimicrobial activity of the CeO2 NPs was assessed in vitro against various bacterial strains, demonstrating a concentration-dependent inhibition zone when exposed to concentrations ranging from 25 to 100 μg/mL. Antitonicity activity results of the synthesized CeO2 NPs revealed significant activity. Further molecular docking studies also revealed that the synthesized CeO2 NPs have better docking ability compared to control Streptomycin in E. coli topoisomerase II DNA gyrase B (PDB ID:1KZN).

Synthesis, spectroscopic characterization, DFT analysis, antibacterial, antifungal, antioxidant, molecular docking, and ADME study of 3,4-dihydro-2H-napthalen-1-one tagged chalcone derivatives

Chalcone derivatives were synthesized from 3,4-dihydro-2H-naphthalen-1-one using a base-catalyzed Claisen-Schmidt reaction and characterized by FT-IR, ¹H NMR, and ¹³C NMR spectroscopy. Density functional theory (DFT) with the B3LYP/6-311G(d,p) basis set was employed to explore the structural, electronic, and quantum properties of the compounds. Simulated electronic absorption spectra for compounds 3c and 3e in gas phase, DMSO, and DCM were generated using time-dependent DFT (TD-DFT). Compound 3c's first singlet excited state shifted from 376.10 nm in the gas phase to 390.08 nm in DMSO, while compound 3e shifted from 381.58 nm to 383.54 nm in DMSO. Experimental absorption values matched the theoretical predictions, with higher oscillator strengths in DMSO and DCM indicating solvent-enhanced transition probabilities. The antimicrobial activity of the chalcones was evaluated against four bacterial strains (E. coli, B. subtilis, S. aureus, and Streptococcus spp.) and four fungal strains (R. oryzae, P. chrysogenum, A. niger, and C. albicans). Compounds 3d and 3f showed strong antibacterial activity with MIC values of 3.9 µg/mL and moderate antifungal activity. Antioxidant properties were assessed using DPPH and hydroxyl radical assays, with compound 3d demonstrating 75.8 % and 76.4 % scavenging activity for OH and DPPH radicals, respectively. ADME studies were conducted to evaluate pharmacokinetics, and molecular docking studies revealed strong binding affinities. Compounds 3a and 3e had docking scores of -8.7 kcal/mol with the E. coli protein (PDB ID: 1KZN), while 3d and 3f performed best against B. subtilis (PDB ID: 1BAG) and S. aureus gyrase (PDB ID: 2XCT), with scores of -9.1 and -8.3 kcal/mol, respectively. Molecular dynamics simulation of compound 3d with 1BAG over 100 ns confirmed stable binding. These findings suggest chalcone derivatives have strong potential for pharmaceutical development.

Antifouling and antibacterial study of PSf/bio-ZnO nanoparticle (bio-ZnO NP) mixed matrix membrane for humic acid separation

Antifouling and antibacterial study of PSf/bio-ZnO nanoparticle (bio-ZnO NP) mixed matrix membrane for humic acid separation

Chitosan supported hetero-metallic bio-nanocomposites for paracetamol removal from homogeneous solutions and heterogeneous mixtures with focused antibacterial studies

Biopolymers infused with bimetallic nanoparticles exhibit a wide range of functionalities necessary for efficiently eliminating diverse water contaminants. However, the protracted production process requires further exploration. As such, present study seeks to optimize microwave-assisted technique for the facile synthesis of cross-linked chitosan (CTS) supported bimetallic-oxide nanoparticles, specifically zinc oxide (ZnO) and iron-oxide (Fe3O4), denoted as CTS-TTP/Zn-Fe. The primary objective is to investigate the efficacy of these beads in the removal of Paracetamol (PCM) from single and complex water matrices while also assessing their antibacterial properties. Characterization includes chemical composition, surface structures, thermal stability, and magnetic properties. The experimental results demonstrated that CTS-TPP/Zn-Fe beads achieved a remarkable PCM removal efficiency of ~99 % (qm = 4.98 mg g−1), with a Zn:Fe mole ratio of 1:1. The experimental data showed good applicability with Freundlich isotherm and chemisorption-supported rate models (R2 > 0.9). To evaluate the long-term viability and practicality of these beads, three crucial field applicability tests were conducted. These encompassed competition studies with other pharmaceuticals, desorption investigations for repeated use, and efficiency evaluations in an ionic solution. Collectively, this research provides a comprehensive understanding, spanning from material design to practical applications, with potential relevance for large-scale wastewater treatment when coupled with appropriate flux control measures.

EFFECT OF BORIC ACID ADDITION ON ANTIBACTERIAL DYE PRODUCTION

In this study, the use of interior dyes with antibacterial properties was examined. Boric acid (H3BO3), which is a cheap and easily obtainable boron compound from our country's resources, has an antibacterial effect. Within the scope of the study, firstly, boric acid mixtures were prepared in appropriate concentrations and antibacterial dye production studies were carried out by adding them to indoor dyes. The antibacterial properties of the obtained dye were investigated through the inhibition effect on E. coli bacteria and its antibacterial activity was tested, and then the brightness, density, film thickness, scorching, pencil hardness and drying time tests of the dyes and the suitability of their characteristics to TS 5808/2012 and the applicability of these dyes were evaluated. The results showed that the antibacterial effect of boric acid did not have a negative effect on the dye quality, but maintained the standard values of the dye.

High-frequency ultrasound modulation of Zn2+ release from nanoclay supported ZnO antibacterial composites

Bacterial infections pose considerable health risks, emphasising the critical need for effective and biocompatible antibacterial drugs. Considerably, we developed an efficient antimicrobial system incorporating the combined potential of high-frequency ultrasound and antimicrobial drugs against bacterial infections. A ZnO–kaolinite (Kaol) composite with antibacterial properties was synthesised by growing ZnO on the Kaol nano-clay surface using the co-precipitation method. High-frequency ultrasound efficiently promotes the release of Zn2+, which enhances the antibacterial properties. Furthermore, in-depth in vitro antibacterial studies and bacterial live/dead staining experiments validate the exceptionally high antibacterial performance of the composite. Therefore, owing to the synergistic effects of high-frequency ultrasound and antibacterial properties, the as-prepared novel antibacterial composite is a promising potential substitute for conventional antibacterial agents.

Bioengineered Nickel Oxide Nanofabrication for Energy Storage Systems, Degradation of Refractory Water Toxicity, and Antibacterial Study

AbstractNickel oxide (NiO) nanoparticles were synthesized using a green method involving Pterolobium hexapetalum flower extract as the reducing agent. Synthesized nickel oxide nanoparticles (NiO NPs) were thoroughly characterized using X‐ray diffraction, UV–vis spectroscopy, Fourier‐transform infrared spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analysis. The XRD analysis confirmed the pure formation of NiO NPs. TEM and SEM images revealed the size, shape, and surface morphology of the nanoparticles. BET analysis indicated a high surface area, making these nanoparticles suitable for various applications. The NiO NPs were further investigated for their potential in supercapacitor applications, demonstrating excellent electrochemical performance. NiO@rGO electrode with graphene proportion showed a maximum specific capacity of 1266 Fg−1 at 1 Ag−1. Moreover, following the 3000‐cycle assessment, the specific retention of 98.2% confirmed that the electrode had high cyclic stability. Additionally, their effectiveness in dye degradation was evaluated, showing promising results in removing organic dyes from wastewater. The antibacterial activity of the NiO nanoparticles was also assessed, indicating significant inhibition against various bacterial strains. These multifaceted studies suggest that NiO NPs synthesized from plant extract hold great promise for applications in energy storage, environmental remediation, and antimicrobial treatments.

Physico-mechanical properties, hydroxyapatite conversion, biodegradability and antibacterial activity studies of melt-derived BGs based on SiO2-CaO-Na2O-P2O5 quaternary system

The slow biodegradation and low hydroxyapatite (HA) conversion of silicate-based bioactive glasses (BGs) have severely limited their compatibility with biological tissues. To address these challenges, four samples in the form of (52-x)SiO2-24Na2O-24CaO-xP2O5, where x is 2, 4, 6, and 8 mol%, were prepared by a unified melt-quenching method, and the feasibility of P2O5 content fine-tuning in improving glass structure, biodegradability, bioactivity, and antibacterial efficiency was evaluated. The results indicated that as the degree of P2O5 substitution increased, the network structure of the glass became looser, which provided favourable conditions for its degradation. The variation in activation energy for Si4+ ion release from 0.39 eV to 0.25 eV also supported this observation. After 7 days of immersion in simulated body fluid (SBF), analyses by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) confirmed that the Ca-P compounds deposited on the glass surfaces were essentially hydroxycarbonated apatite (HCA), and scanning electron microscopy (SEM) images revealed that the generation rate of the HCA were positively correlated with the P2O5 content in the glass system. Meanwhile, antibacterial studies showed that after 24 h of incubation, the antibacterial activity of the four glass samples against Escherichia coli (E. coli) successively increased, with the highest percentage reaching 87.13 ± 2.51 %. In conclusion, this study demonstrates that controllable degradation and high-level bioactivity can be achieved by modulating the P2O5 content in silicate-based BGs, which proves to be an effective and practicable strategy.

Extraction of Anacardium occidentale: a kinetic, thermodynamic, phytochemical identification, and antibacterial study

Cashew tree biomass, Anacardium occidentale, represents an underutilized part of the plant and could have great potential for application in several areas, such as bioengineering, food science, and chemical. The stirred bed process was optimized to produce extracts from Anacardium occidentale stem bark (SBAo) and leaves (LAo) for bactericide purposes. Variables as alcohol content, stirring speed (SS), particle size (PS), solid-to-solvent ratio (S/S), temperature, and extraction time were evaluated. Subsequently, kinetic, thermodynamic and diffusivity fittings of the data were performed using different nonlinear models (Peleg, 2nd order, Elovich, power law, and Fick’s 2nd law) applied to the yield curves. Extracts were characterized by Fourier-transform infrared (FTIR) spectroscopy, total phenolic content (TPC), total flavonoid content (TFC), trolox equivalent antioxidant capacity (TEAC), and ultra-high resolution mass spectrometry (UHRMS) techniques for qualitative and quantitative determination of the phytochemicals. The optimized operating conditions obtained were ethanol in solvent at 70%, PS < 45 μm, 1200 rpm SS, 1/10 S/S ratio, and extraction time of 1 h at 50 ºC. The 2nd order kinetic model was the one that presented the best fits: SBAo (R2 > 0.9893 and RMSE < 3.4293) and LAo (R2 > 0.9985 and RMSE < 3.1117). Both A. occidentale extracts showed high levels of polyphenols and flavonoids, such as anacardic acid. Finally, the optimized extracts showed antibacterial susceptibility, with larger halos against S. aureus, 0.88± 0.07 mm (SBAo) and 0.45 ± 0.03 mm (LAo), in relation to E. coli, 0.80 ± 0.10 mm (SBAo) and 0.69 ± 0.08 mm (LAo).

Clarithromycin-tailored cubosome: A sustained release oral nano platform for evaluating antibacterial, anti-biofilm, anti-inflammatory, anti-liver cancer, biocompatibility, ex-vivo and in-vivo studies

The clinical implication of clarithromycin (CLT) is compromised owing to its poor solubility and, subsequently, bioavailability, unpalatable taste, rapid metabolism, short half-life, frequent dosing, and adverse effects. The present investigation provides an innovative sustained-release oral drug delivery strategy that tackles these challenges. Accordingly, CLT was loaded into a cubosome, a vesicular system with a bicontinuous cubic structure that promotes solubility and bioavailability, provides a sustained release system combating short half-life and adverse effects, masks unpleasant taste, and protects the drug from destruction in gastrointestinal tract (GIT). Nine various formulas were fabricated using the emulsification method. The resulting vesicles increased the encapsulation efficiency (EE %) from 57.64 ± 0.04 % to 96.80 ± 1.50 %, the particle size (PS) from 147.30 ± 21.77 nm to 216.61 ± 5.37 nm, and the polydispersity index (PDI) values ranged from 0.117 ± 0.024 to 0.278 ± 0.073. The zeta potential (ZP) changed from −20.65 ± 2.01 mV to −33.98 ± 2.60 mV. Further, the release profile exhibited a dual release pattern within 24 h., with the percentage of cumulative release (CR %) expanding from 30.06 ± 0.42 % to 98.49 ± 2.88 %, optimized formula was found to be CC9 with EE % = 96.80 ± 1.50 %, PS = 216.61 ± 5.37 nm, ZP = −33.98 ± 2.60 mV, PDI = 0.117 ± 0.024, CR % = 98.49 ± 2.88 % and IC50 of 0.74 ± 0.19 µg/mL against HepG-2 cells with scattered unilamellar cubic non-agglomerated vesicles. Additionally, it exhibited higher anti-MRSA biofilm, relative bioavailability (2.8 fold), and anti-inflammatory and antimicrobial capacity against Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus compared to free CLT. Our data demonstrate that cubosome is a powerful nanocarrier for oral delivery of CLT, boosting its biological impacts and pharmacokinetic profile.

Synthesis, characterization, antibacterial, antioxidant and molecular docking studies of Zn(II) complexes with imine quinoline derivative ligand

The efficacy of metal complexes with bioactive ligands for pharmaceutical purposes is increasingly gaining clinical and commercial importance for treating infectious diseases. This research aimed to synthesize new Zn(II) complexes, assess their potential applications in antibacterial and antioxidant properties, and explore their molecular docking properties. The synthesis was done by condensing 7-chloro-2-hydroxyquinoline-3-carbaldehyde and 2,2′-thiodianiline with Zn(II) metal complexes. A range of spectroscopic techniques, such as 1H and 13C NMR, FTIR, TG/DTA, pXRD, and UV–Vis, were employed to characterize both the ligand and its complexes. Imine quinoline ligand (L), ZnL, and ZnL2 all had average crystallite diameters of 13.28, 21.19, and 16.26 nm, respectively, according to pXRD analysis, which confirmed that the synthesized ligand and its Zn(II) complexes showed polycrystalline properties. Based on the results, an octahedral geometry was proposed for the complexes. A very good agreement was obtained between the experimental and the TD-DFT calculated absorption peaks. Their biological potency against Gram-positive (Staphylococcus aureus ATCC 25926) and Gram-negative (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 248) bacterial strains as well as antioxidant properties were tested. The ZnL complex showed a maximum growth inhibition of 9.50 ± 0.41 mm against S. aureus ATCC 25926; whereas the maximum growth inhibition of the ZnL2 complex was 9.67 ± 0.47 mm and 9.33 ± 0.47 mm against ATCC 25926, respectively. With an IC50 of 167.3 ± 1.04 mg/mL, ZnL had the strongest antioxidant activity against DPPH radicals. All the complexes had strong binding affinities according to the molecular docking investigation: L (−11.31 kcal/mol), ZnL (−11.38 kcal/mol), and ZnL2 (−13.51 kcal/mol) against the active sites of S. aureus and (−7.92, −8.07, and −8.92) kcal/mol, respectively, against the active sites of E. coli. The Zn(II) complexes had the highest potency of biological activity.

Surface modification of surgical suture by chitosan-based biocompatible hybrid coatings: In-vitro anti-corrosion, antibacterial, and in-vivo wound healing studies

This work aims to develop chitosan-based biocompatible hybrid coatings on synthetic surgical sutured by direct current electrophoretic deposition (DC-EPD) method. The chitosan (CS), curcumin (CR), aloe-vera (AV), and 2-aminothiazolidin-4-one-5-ethanoic acid (AT) were used as suspensions of varying combinations and compositions (A–I). Each suspension has a further 05 samples (Aa–Ae–Ia–Ie) at selected DC-EPD set parameters (2–10 V, t; 240 s, D; 1 cm). Potentiodynamic polarization measurements (PDP) were carried out in the ringer solution. Among all samples, Ed (CS, 1.6 g/L; 8 V) and Hb (CS–CR–AT, 1.6 g/Leach; 4 V) have shown greatest corrosion inhibition efficiency (IEPDP: 99 %), least corrosion rates (CR; 0.001 mm/y and 0.017 mm/y, respectively), and least corrosion current density (Icorr.; 0.01 A cm−2). SEM and FTIR further confirmed these two best coatings stable and corrosion resistant before and after performing corrosion test, while the coating thickness by profilometry test was found to be greater (16.28 μm) for Hb. Mechanical stress and strain of bare and coated samples were found to have no significant difference. Antibacterial activity revealed greater resistance of Hb against S. aureus as compared to Ed. In-vivo incision wound model study further revealed better healing and less inflammation with coated sutures with comparatively enhanced wound healing effect of Hb coated suture.

Identification of novel antistaphylococcal hit compounds.

Staphylococcus aureus is one of the most common nosocomial biofilm-forming pathogens worldwide that has developed resistance mechanisms against majority of the antibiotics. Therefore, the search of novel antistaphylococcal agents with unexploited mechanisms of action, especially with antibiofilm activity, is of great interest. Seryl-tRNA synthetase is recognized as a promising drug target for the development of antibacterials. We have carried out molecular docking of compounds with antistaphycoccal activity, which were earlier found by us using phenotypic screening, into synthetic site of S. aureus SerRS and found seven hit compounds with low inhibitory activity. Further, we have performed search of S. aureus SerRS inhibitors among compounds which were previously tested by us for inhibitory activity toward S. aureus ThrRS, that belong to the same class of aminoacyl-tRNA synthetases. Among them six hits were identified. We have selected four compounds for antibacterial study and found that the most active compound 1-methyl-3-(1H-imidazol-1-methyl-2-yl)-5-nitro-1H-indazole has MIC values toward S. aureus multidrug-resistant clinical isolates ranging from 78.12 to 156.2 µg/ml. However, this compound precipitated during anti-biofilm study. Therefore, we used 3-[N'-(2-hydroxy-3-methoxybenzylidene)hydrazino]-6-methyl-4H-[1,2,4]triazin-5-one with better solubility (ClogS value = 2.9) among investigated compounds toward SerRS for anti-biofilm study. It was found that this compound has a significant inhibitory effect on the growth of planktonic and biofilm culture of S. aureus 25923 with MIC value of 32 µg ml-1. At the same time, this compound does not reveal antibacterial activity toward Esherichia coli ATCC 47076. Therefore, this compound can be proposed as effective antiseptic toward multidrug-resistant biofilm-forming S. aureus isolates.

Enhanced Antibacterial Activity of Levofloxacin with Cucurbit[7]uril-Functionalized Gold Nanoparticles.

Bacterial infection is one of the major concerns of the growing society, and over the years, different permutations and combinations of various drugs and adjuvants have been attempted, which led to considerable improvements in the efficacy of the antibacterial drugs. In this regard, macrocyclic receptors such as cyclodextrin, cucurbiturils, calixarene, etc., have played a major role by modulating the drug properties that supplement the antibacterial efficacy. In this study, we have developed cucurbit[7]uril (CB7)-functionalized Au nanoparticles (CB7AuNPs) to modulate the activity of an antibiotic, levofloxacin (LOFL). From the spectroscopic and thermodynamic changes in the LOFL, it has been established that two of the prototropic forms, LOFLH and LOFLH2+, form strong 1:1 host/guest complexes with CB7/CB7AuNP. Both these interactions led to significant upward shifts in the pKa values as well as photostability of LOFL, thereby enhancing the availability of the active form for the antibacterial activity, at the physiological pH. Further, the LOFL uptake has also been established on CB7AuNP, which retained the CB7-LOFL activity at very low concentration of the CB7 host, functionalized on AuNP. Detailed antibacterial studies of LOFL, both as complexed with CB7 and CB7AuNP, were carried out using four food-borne pathogens (Escherichia coli, S. Typhimurium, Bacillus cereus, and Staphylococcus aureus), which revealed a creditable enhancement in the antibacterial property, irrespective of the bacterium strain. These results are quite promising at this stage for the development of drugs customized for multidrug-resistant bacteria.

In-silico ADME Evaluation and Molecular Docking of a Novel Compound’ 2-(4-Allylpiperazin-1-Yl)-1-(1-(4-Nitrophenyl)-1h-Tetrazol-5-Yl) Ethanone’ as Potential Antimicrobial Agents.

Molecular docking serves as a pivotal tool in comprehending drug-receptor interactions within modern-day drug design. In a previous report, new compounds 2-(4-allylpiperazin-1-yl)-1-(1-aryl-1H-tetrazol-5-yl) etalons were analyzed. Among these compounds, ‘2-(4-allylpiperazin-1-yl)-1-(1-(4-nitrophenyl)-1H-tetrazol-5-yl)ethanone’ was singled for molecular docking as it shows dual antibacterial and antifungal studies. Docking investigations revealed promising binding affinity of the compound towards Escherichia coli (1KZN), exhibiting significant antibacterial activity of docking grade -5.53 Kcal/mol, indicative of a fortified binding interaction. Conversely, the compound exhibited weaker binding affinity towards Candida albicans (1AI9) with a docking grade of -0.72 Kcal/mol. Negative binding energy signifies a robust alignment between the ligand and target protein, suggesting potential therapeutic efficacy against microbial activity. Moreover, in-silico ADMET calculations were conducted, and the synthesized compound confirms the drug-likeness within the defined parameters: molecular weight between 150 to 500 g/mol, TPSA polarity between 20 to 130 Å2 , lipophilicity ranging between -0.7 to +5.0 Log S not exceeding 6, flexibility not exceeding 9, and saturation not inferior to 0.25. The compound demonstrated compliance with these criteria, suggesting favorable in-vivo drug absorption and permeation characteristics.

Synthesis, Characterization and Antibacterial Studies of New Crown Ether Prodrugs.

New three esters (E1, E2 and E3) from crown ethers and drugs were prepared by Stiglich esterification. These procedures began with the reaction of certain quinolones (levofloxacin, ciprofloxacin, and nalidixic acid) with thionyl chloride to produce a considerably more potent acylating agent. Next, for the production of ester prodrugs, 2-hydroxymethyl-15-crown-5 ether (a lariat crown ether) was esterified using an acid chloride in the presence of pyridine. These molecules were synthesized as carrier-mediated prodrugs in order to solve different pharmacokinetic and pharmacological difficulties, enhance physicochemical features, and augment the antibacterial efficacy of the parent drugs by structural modifications while avoiding bacterial resistance. The compounds` structures were verified by FTIR, UV, H1 &amp; 13C-NMR spectroscopy and certain physiochemical qualities. In a concentration-dependent manner, all of the synthesized prodrugs’ biological studies revealed improved activity against certain bacterial species.

Dual sustainability of rGO/CuCoO2 nanocomposites with enhanced photocatalytic and antibacterial insights

New growth and photocatalytic activity of CuCoO2 and rGO/CuCoO2 nanocomposites were demonstrated for model organic pollutant (dye) and antibacterial studies. The rGO/CuCoO2 nanocomposites were designed by hydrothermal technique. CuCoO2 and rGO/CuCoO2 materials were investigated and characterized by several instrumental techniques like FT-IR spectroscopy (FT-IR), Raman spectroscopy, X-Ray diffractometer (XRD), DRS-UV Visible spectroscopy, HRTEM, FESEM analysis, Thermogravimetric analysis (TGA) and BET investigations. XRD confirmed the CuCoO2 cubic phase structure. It seems to have been evaluated for FT-IR and the Raman results were better than anything else that should be satisfied. Hence, Cu–O or Co-O (M−O−M) modes were confirmed peaks at 400 to 900 cm−1. We proposed CuCoO2 and rGO/CuCoO2 ((25/75), (50/50) & (75/25)) composite materials band gap energies at 2.8 eV to 2.0 eV. So, these results are also one of the benefits in the application area. A Sedum morganianum Burrito − Burro’s plant’s tail-like morphology was obtained in the pure CuCoO2 materials, and different weight percentages of rGO composites were also identified in FESEM-analysis as wood fungi, rods, and sheets-like structures. The rGO/CuCoO2 sheet-like morphology was confirmed by HRTEM measurements. The elemental composition of materials was investigated by EDX spectroscopy. We can prepare to suggest that the synthesis potential in the prepared matter is tbepensumed Bache formulation and much less explored, first-time declared phases and novelty of the synthetic designs, new morphologies, and bandgap energies. The synthesized rGO/CuCoO2 materials were achieved by 94 % Methylene blue (MB) dye degradation in photocatalytic applications, in which case composites were more efficient with environment-friendly when compared to CuCoO2 nanoparticles. The role of the rGO composite can be divided into three different principles such as absorbance, charge separator, and photosensitizer. This rGO material can reflect a big absorption capacity depending on the dye to rGO, with parallelly obeyed for π-π interactions. Hence, it’s favored for catalytic improvement. Secondly, rGO degradation was improved to the charge separation and may be foiling for the recombination of electron-hole pairs. Finally, transform their wide bandgap semiconductor into the catalyst to facilitate parameters. The rGO/CuCoO2 composite materials have performed well in reusability and radical abilities. The antimicrobial activity of the CuCoO2 nanoparticle was investigated on Gram-positive Staphylococcus aureus &Enterococcus faecalis and Gram-negative Escherichia coli &Pseudomonas aeruginosa bacterial strain. As promised rGO/CuCoO2 and CuCoO2 materials were examined for better degradation activities and antibacterial activities. Antibacterial efficacy studies play a major innovative role in the present work and have not been previously published. Hence, we have selected this kind of material.