Antimicrobial Activity Studies Research Articles

A novel isatin Schiff based cerium complex: synthesis, characterization, antimicrobial activity and molecular docking studies

In this work, a novel isatin-Schiff base L2 had been synthesized through a simple reaction between isatin and 2-amino-5-methylthio-1,3,4-thiadiazole. The produced Schiff base L2 was then subjected to a hydrothermal reaction with cerium chloride to produce the cerium (III)-Schiff base complex C2. Several spectroscopic methods, including mass spectra, FT-IR, elemental analysis, UV–vis, 13C-NMR, 1H-NMR, Thermogravimetric Analysis, HR-TEM, and FE-SEM/EDX, were used to completely characterize the produced L2 and C2. A computer simulation was performed using the MOE software program to find out the probable biological resistance of studied compounds against the proteins in some types of bacteria or fungi. To investigate the interaction between the ligand and its complex, we conducted molecular docking simulations using the molecular operating environment (MOE). The docking simulation findings revealed that the complex displayed greater efficacy and demonstrated a stronger affinity for Avr2 effector protein from the fungal plant pathogen Fusarium oxysporum (code 5OD4) than the original ligand. The antibacterial activity of the ligand and its Ce3+ complex were applied in vitro tests against different microorganism. The study showed that the complex was found to be more effective than the ligand.

Synthesis, characterization, antimicrobial activity and molecular docking study of transition metal complexes based on azo coumarin and thiosemicarbazone derivative

Synthesis, characterization, antimicrobial activity and molecular docking study of transition metal complexes based on azo coumarin and thiosemicarbazone derivative

A study of chemical compounds and antimicrobial activities of Vernonia amygdanlina extract from different areas and the age of leaves as animals’ feed additives

Herbal plants have been used as an alternative to replace the use of antibiotics in animal production. African leaves (Vernonia amygdalina) are herbal plants that have medicinal properties. This study was carried out with the purpose of evaluating the biochemical and antimicrobial compounds of African leaf extract as a phytogenic supplement in animal feed. African leaves (V. amygdalina) which grow massively in Aceh were extracted using 96% ethanol solvent in 1:3 ratio. There were 4 African leaf samples differentiated according to young and old leaves that grow in the highlands and lowlands used in this study. Biochemical compound testing was carried out using a qualitative phytochemical screening method and antimicrobial testing (Salmonella and Escherichia coli) using the Kirby Bauer Disc Diffusion method using Salmonella enterica sv Typhimurium ATCC 14028 and E. coli ATCC 25922 bacteria with a Mc Farland standard of 0.5. Phytochemical test results show that African leaves contain alkaloids, steroids, flavonoids and phenolics. Meanwhile, the results of antimicrobial testing did not show inhibition against Salmonella and Escherichia coli bacteria. This research concluded that the extracted leaves of African plants had the potential to be administrated as a phytogenic additional feed.

Photocatalytic Degradation of Rhodamine-B and Water Densification via Eco-Friendly Synthesized Cr2O3 and Ag@Cr2O3 Using Garlic Peel Aqueous Extract

The purification and densification of wastewater play an important role in water recycling, especially if the materials used in water recycling are other types of recycled waste. Therefore, considering this view in this study, the biosynthesis of silver-decorated chromium oxide nanoparticles utilizing a wasted Allium sativum (garlic) peel extract is investigated. The aqueous extract of garlic peel (GPE) was treated with silver nitrate, chromium nitrate, and a mixture of silver nitrate and chromium nitrate to synthesize silver nanoparticles (Ag-garlic), chromium oxide nanoparticles (Cr2O3-garlic), and silver-decorated chromium oxide nanoparticles (Ag@Cr2O3-garlic), respectively. The synthesized nanoparticles were elucidated via thermal gravimetric analysis (TGA), infrared spectra (FT-IR), absorption spectra (UV-Vis), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Antimicrobial activity studies were conducted against waterborne germs, bacterial strains (Bacillus subtilis, Enterococcus faecium, Escherichia coli, and Pseudomonas aeruginosa), and fungal strains (Alternaria porri, Aspergillus flavus, Aspergillus niger, Fuserium oxysporum, and Trichoderma longibrachiatum) and showed significant levels of antimicrobial activity. The results revealed that Ag@Cr2O3 significantly improved antimicrobial activity due to their synergistic effect. The photocatalytic activity of nanoparticles was assessed using Rhodamine B dye (5 ppm) under solar irradiation. Cr2O3-garlic exhibited the best activity as a photocatalyst among the studied nanoparticles, with 97.5% degradation efficiency under optimal conditions.

Chemical Analyses of Volatiles from Kumquat Species Grown in Greece—A Study of Antimicrobial Activity

Chemical Analyses of Volatiles from Kumquat Species Grown in Greece—A Study of Antimicrobial Activity

Spectroscopic characterization, DFT calculations, antimicrobial activity, and molecular docking studies of 5-methoxy-1H-benzo[d]imidazole and its Ag(I) complex

The 5-methoxy-1H-benzo[d]imidazole (5MeOBM) and the synthesized new silver(I) complex were characterized using elemental analysis and spectroscopic methods such as 1H NMR, FT-IR, UV–Vis and mass spectrometry. To compare the spectroscopic results and establish the molecular structures of the free ligand and its metal complex, density functional theory (DFT) computations were performed. UV–Vis spectrum analysis was performed to better understand the optical properties, and quantum chemical properties were computed theoretically utilizing HOMO and LUMO energy levels. Topological analyses were carried out using Multiwfn to identify the complex's primary binding areas and weak interactions. NBO analyses were performed in order to predict potential reactivity features and critical intramolecular interactions. Biological study of the ligand and its Ag(I) complex were tested for their in vitro antimicrobial activities. The molecular docking investigations were performed to explore the possible interaction of each compound with an antimicrobial agent. Also, molecular docking studies were carried out to learn how these compounds interact with biomolecules.

New 2-Chloroimidazo[1,2-a]pyridine induced Schiff bases: Synthesis, characterization, antimicrobial and A-498 and A-549 anticancer activity, molecular modeling, in-silico pharmacokinetics, and DFT studies

The novel 1-(2-chloroimidazo[1,2-a]pyridin-3-yl)-N-(substitutedphenyl) methanimines have been synthesized and characterized by spectral (IR, MS, 1H, and 13C NMR) and elemental analysis. Molecular docking studies were conducted with three cancer target proteins (PDB IDs: 1M17, 2OF4, and 3LCK) and assorted microbial target proteins (1KZN, 2XCT, 1D7U, 1BAG, and 1EA1) to explore their binding interactions. Further in-silico target prediction study suggested a 26.7 % probability that VIf acts on kinases. The synthesized analogs were subjected to in-vitro anticancer activity assessments against A-498 (kidney carcinoma) and A-549 (lung carcinoma) cell lines and compound VIf exhibited good inhibition (GI50<10) of the A-498 cell line. Additionally, all analogs showed moderate to good in-vitro antimicrobial activity against S. aureus, B. subtilis, E. coli, K. pneumoniae (bacterial strains), and C. albicans (fungal strain). The optimized geometries, FMO energies, MEP plots, and global reactivity descriptors (µ, ɳ, S, and ω) were achieved employing DFT at B3LYP/6-31G (d) level to explore structural features and probable reactivity and toxicity of the synthesized compounds. Compound VIg exhibited high reactivity (ɳ: 1.8218 eV, S: 0.2744 eV) and low toxicity (ω: 3.2061 eV) among all analogs. These findings collectively underscore the potential of the synthesized compounds, with VIf and VIg standing out as particularly promising candidates for further exploration.

Study of the Antimicrobial Activity of Staphylococcal Bacteriophage on a Model of an Infected Skin Wound

The purpose of this study was to investigate the antimicrobial activity of staphylococcal bacteriophage on a model of a skin wound infected with Staphylococcus aureus. The study of antimicrobial activity was carried out in vivo by experimental modeling of a skin wound infected with S.aureus in the interscapular region in nonlinear male rats. All manipulations with animals were performed in accordance with the requirements of regulatory documentation overseeing the management of laboratory animals and work with them. The results obtained indicate the pronounced antimicrobial activity of staphylococcal bacteriophage in conditions of wound infection when applied externally, which is confirmed by a decrease in the degree of bacterial contamination of wound discharge, as well as a decrease in inflammatory phenomena, both at the local level in the form of a decrease in hyperemia, and generalized in the form of a decrease in C-reactive protein levels, total leukocyte count, as well as a decrease in the leukocyte inflammatory index. The identified antimicrobial effect is comparable to the external use of an antiseptic drug — a solution of chlorhexidine digluconate 0.05%, however, when assessing microbial contamination, it was found that the bacteriophage exhibits more pronounced antibacterial activity. Thus, the staphylococcal bacteriophage showed pronounced antimicrobial activity in a model of a skin wound infected with S.aureus, confirmed by a decrease in the number of colonies of the microorganism in the wound discharge, as well as a decrease in the severity of inflammation.

Solvent role in molecular structure level, structural and topology investigations, molecular docking and antimicrobial activity studies on sulpha drug derivative

The Schiff base (5FSATH) was synthesized and characterized by different experimental techniques. In the context of local energy decomposition analysis (LED), the binding energy of 5FSATH-water interaction is determined to be -15.63 kcal/mol, while the bond distance between the two objects is measured to be 1.9781 A°. The absorption spectrum was recorded using different solvents like DMSO, water, and chloroform. The experimental absorption spectrum wavelengths 206, 220, and 300 nm, were recorded from DMSO solvent. In the emission (fluorescence) spectrum we observed three different wavelengths such as 352, 510, and 609 nm. For the calculated NMR spectrum, used the standard GIAO method and DMSO as the solvent. The HOMO-LUMO analysis indicates the charge transfer within the molecule, it is calculated by different solvents. NBO confirms the synthesized compound stability, hyper conjugative interaction, and charge delocalization. To test for antibacterial and antifungal activity, an agar disc well diffusion method is utilized. Synthesized compound tested against Escherichia coli, Candida albicans, Staphylococcus aureus, and Streptococcus pneumoniae microorganisms. Amoxicillin was used as the reference drug for testing antibacterial and antifungal activity. According to the findings of the antimicrobial activity, the result of the molecular docking experiment showed that the compound 5FSATH had an extremely high binding affinity score.

Study of Antimicrobial Activity &amp; Structural Elucidation of Purified Compound from Potential Solvent Extract of Bruguiera cylindrica [L

Study of Antimicrobial Activity &amp; Structural Elucidation of Purified Compound from Potential Solvent Extract of Bruguiera cylindrica [L

Ginger essential oil-loaded hydrogels: preparation, characterization, cytotoxicity, antimicrobial and anti-inflammatory activity

ABSTRACT The present study aimed to develop ginger essential oil hydrogel formulations, using sodium carboxymethyl cellulose (Na CMC), Carbopol, and xanthan gum for dental and oromucosal infections. The physicochemical properties of the hydrogels were evaluated, and their bioadhesive characteristics were determined. Antimicrobial activity, cytotoxicity, and lipoxygenase (LOX) inhibitory activities of the essential oil and its formulations were investigated, respectively. The major components of ginger essential oil were confirmed as α-zingiberene (39.0%) and ar-curcumene (23.7%) by GC-FID and GC/MS analyses. The initial results showed that none of the tested gel formulations selected for the application were non-cytotoxic. According to antimicrobial and LOX enzyme activity studies, the essential oil-loaded xanthan gum gel (X3) was more effective compared to the essential oil itself. The initial formulation and biological evaluation studies concluded that ginger essential oil hydrogels (X3, C3) can be further developed for oral and dental health by providing a long residence time due to their bioadhesive properties.

Study of antimicrobial activity and fermentability of the yeast Wickerhamomyces anomalus in wheat dough

The work is aimed at assessing the potential of using the yeast culture Wickerhamomyces anomalus CBS605T in bread baking. The in vitro antimicrobial activity of the yeast culture Wickerhamomyces anomalus (CBS605T) against the causative agent of potato disease, Bacillus subtilis, was studied. A rheoenzymemetric assessment of the gas-forming and gas-retaining abilities of the studied strain during fermentation in wheat dough was carried out. The study showed that the yeast culture Wickerhamomyces anomalus (CBS605T) effectively inhibits the growth of Bacillus subtilis and has higher fermentation activity than the control organism Saccharomyces cerevisiae var. boulardii (Y3925), also known for antimicrobial activity against the pathogen of potato disease.

Search for new biologically active compounds: in vitro studies of antitumor and antimicrobial activity of dirhodium(II,II) paddlewheel complexes.

Four neutral Rh1-Rh4 complexes of the general formula [Rh2(CH3COO)4L2], where L is an N-alkylimidazole ligand, were synthesized and characterized using various spectroscopic techniques, and in the case of Rh4 the crystal structure was confirmed. Investigation of the interactions of these complexes with HSA by fluorescence spectroscopy revealed that the binding constants Kb are moderately strong (∼104 M-1), and site-marker competition experiments showed that the complexes bind to Heme site III (subdomain IB). Competitive binding studies for CT DNA using EB and HOE showed that the complexes bind to the minor groove, which was also confirmed by viscosity experiments. Molecular docking confirmed the experimental data for HSA and CT DNA. Antimicrobial tests showed that the Rh2-Rh4 complexes exerted a strong inhibitory effect on G+ bacteria B. cereus and G- bacteria V. parahaemolyticus as well as on the yeast C. tropicalis, which showed a higher sensitivity compared to fluconazole. The cytotoxic activity of Rh1-Rh4 complexes tested on three cancer cell lines (HeLa, HCT116 and MDA-MB-231) and on healthy MRC-5 cells showed that all investigated complexes elicited more efficient cytotoxicity on all tested tumor cells than on control cells. Investigation of the mechanism of action revealed that the Rh1-Rh4 complexes inhibit cell proliferation via different mechanisms of action, namely apoptosis (increase in expression of the pro-apoptotic Bax protein and caspase-3 protein in HeLa and HCT116 cells; changes in mitochondrial potential and mitochondrial damage; release of cytochrome c from the mitochondria; cell cycle arrest in G2/M phase in both HeLa and HCT116 cells together with a decrease in the expression of cyclin A and cyclin B) and autophagy (reduction in the expression of the protein p62 in HeLa and HCT116 cells).

Antimicrobial activity and molecular docking studies of some imidazo[2,1-b]thiazole derivatives

The synthesis of bioactive molecules is of major importance in the pharmaceutical industry. In this context, the study was conducted to determine the antimicrobial and antifungal potential of four chalcone-based imidazo[2,1-b]thiazole derivatives already synthesized by our research group. The synthetized compounds obtained in good yield were evaluated for their antibacterial and antifungal activities against E. coli, Staphylococcus aureus, Pseudomonas aeruginosa and Fusarium, the results obtained are compared with the standard. Molecular docking studies were utilized to forecast the potential of these molecules as antimicrobial agents, the results obtained in vitro antibacterial were well confirmed by this method.

Novel 1, 2, 3-triazolic compounds derived from cytosine: Synthesis, spectroscopic characterization, in vitro antimicrobial activity and molecular docking studies

The development of novel antimicrobial drugs is crucial due to the increasing problem of antibiotic resistance. A new series of 1,4-disubstituted-1,2,3-triazole derivatives containing a cytosine moiety (3a, 3b, 3c and 3d) were synthesized using 1,3-dipolar cycloaddition in a mixture of ethanol and water under Cu(I)-catalyzed with N-alkyl: 1-(prop-2-ynyl)-4-amino-2-oxopyrimidine 2 as dipolarophiles and azide derivatives (sucre-azoture) as dipoles. The desired products were obtained in good yields by reacting with a catalytic amount of copper (II) sulfate and sodium ascorbate. The structure of these compounds was analyzed and characterized using spectroscopic measurements such as 1H NMR, 13C NMR, and mass spectroscopy. Encouragingly, all cycloaddition molecules exhibited promising activity against various bacterial strains including Staphylococcus aureus and Escherichia coli. The crystal structure modeling of protein 7AZ5 demonstrated strong binding affinities through hydrogen bonds with these molecules. The cycloaddition compounds displayed the highest binding energies in terms of antimicrobial efficacy. This suggests that these substances could serve as an effective model for the development and production of new and potent antimicrobial agents.

Vitex Negundo-Fe3O4-CuO green nanocatalyst (VN-Fe3O4-CuO): synthesis of pyrazolo[3,4-c]pyrazole derivatives via the cyclization of isoniazid with pyrazole and their antimicrobial activity, cytotoxicity, and molecular docking studies.

In this study, we developed a novel pyrazolo[3,4-c]pyrazole derivative with antibacterial and antifungal activities that shows great potential for treating infectious diseases. To evaluate the binding affinity of 1AJ0 and 1AI9 proteins for developing potent antibacterial and antifungal compounds, we used the Vitex negundo (VN) leaf extract as the capping and reducing agent and reacted it with Fe2O3 and Cu(OAc)2 solutions to synthesize the VN-Fe3O4-CuO nanocatalyst. The newly synthesized compounds were confirmed using Fourier transform infrared spectroscopy, transmission electron microscopy, UV-visible spectroscopy, and X-ray diffraction analyses. Antibacterial screening revealed that compound 1g was highly active against Escherichia coli (MIC: 1 μg mL-1) and was much more effective than the standard ciprofloxacin. Compound 1b showed a higher antifungal activity than clotrimazole against Candida albicans (MIC: 0.25 μg mL-1) and cytotoxic activity against MCF-7 cancer cell lines. Compounds 1a-1l were exhibited low cytotoxicity activity compared to the standard doxorubicin (LC50: 21.05 ± 0.82 μg mL-1). To further support the discovery of new active antibacterial agents, compounds 1g and 1b and proteins 1AJ0 and 1AI9 were examined using the AutoDock Vina program and were compared with the standards ciprofloxacin and clotrimazole. With the 1AJ0 protein, compound 1g had a higher docking score (-3.7 kcal mol-1) than ciprofloxacin (-5.6 kcal mol-1), and with the 1AI9 protein, compound 1b had a higher docking score (-4.8 kcal mol-1) than clotrimazole (-4.4 kcal mol-1). Additionally, molecular dynamics simulation was used to investigate the most probable binding mode of compounds 1b and 1g with 1AI9 and 1AJ0, respectively. The VN-Fe3O4-CuO catalyst was used to prepare pyrazolo[3,4-c]pyrazole derivatives, which were successfully characterized and screened for antimicrobial and cytotoxic activities, molecular docking, and molecular dynamics simulation studies.

Isolation and Screening of Pigment Producing Bacteria from Soil and Study of Antimicrobial Activity of Pigments

Pigments are colored compounds that play important roles in various biological systems, such as photosynthesis, vision, and signalling. Pigment-producing bacteria are a diverse group of microorganisms that can produce a wide range of pigments with different colors and properties. The present study is aimed to isolate the pigment-producing bacteria from the soil with the antibacterial activity of pigments. Soil samples were collected from nearby Karad city. All eight different pigmented colonies were isolated that produced the pigments like Yellow, Red, Golden Yellow, and Orange and they were designated as YP-I, YP-II, YP-II, GYP-I, GYP-II, RP-I, RP-II, and OP. The isolated organisms were characterized with the help of Bergey’s Manual of Determinative Bacteriology. The pigments were extracted with a solvent like chloroform and the antibacterial activity of the extract was tested against E. coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The extracted pigments had an inhibitory effect on both Gram-positive and Gramnegative bacteria. The pigments of isolates designated as YP-III, GYP-I, GY-II, and RP-II showed the highest antibacterial activity against E. coli.

The effects of Equisetum arvense L. extracts prepared using different solvents and extraction methods for antioxidant and antimicrobial activity

Our study aimed to determine the solvent and extraction method that reveals the biological activities and phenolic contents of the plant Equisetum arvense at the maximum rate. Leaf and stem extracts of Equisetum arvense were prepared using the soxhlet and maceration method in the presence of 5 different solvents. The extracts' total phenolic content (TPC) was determined using the Folin-Ciocalteu method, the antioxidant activity by the DPPH radical scavenging test, and the antimicrobial activity by the disc diffusion method. When the antibacterial activity results were examined, the methanolic leaf extract prepared by the maceration method showed the inhibition zones as 14.5 mm on S. aureus, 14.2 mm on S. epidermidis and 14 mm on E. faecalis. From leaf parts, it was determined that the methanolic extract prepared by the soxhlet method was 85.1%, the acetonic extract 84.5%, the methanolic extract prepared by the maceration method 83%, and the acetonic extract 84.1% scavenged DPPH radical. As a result of the study, it was determined that the maceration method showed better results in evaluating the total phenolic substance amount and antimicrobial activity and the soxhlet method in determining the antioxidant activity. It has been determined that methanol and acetone were the ideal solvents for TPC antioxidant and antimicrobial activity studies to be carried out with E. arvense plant. In this study, plant leaves and stems were studied separately for the first time and their biological activities were compared. In addition, our study provides integrative data investigating and comparing the antioxidant and antimicrobial activities of the E. arvense plant in detail with various solvents and methods.

Antimicrobial activity study of some binuclear complexes with Schiff bases derived from an aromatic dialdehyde and some amino acids

Many metal complexes with amino acid derived Schiff bases have been synthesized and tested for their biological activity. Thus, the aim of the present study was to evaluate the antimicrobial activity of some binuclear complexes with Schiff bases derived from an aromatic dialdehyde and some amino acids by studying the influence of the tested compounds on the development of microbial biofilms on an inert substrate. The biofilms developed on inert substrate by Klebsiella pneumoniae ESBL+, Citrobacter freundii 1748, Bacillus sp., Serratia marcescens 0804, Staphylococcus aureus ATCC 25923 and Escherichia coli 1576 strains were inhibited at concentrations of the tested compounds between 250 μg∙mL-1 and 500 μg∙mL-1. The results of determining the influence of the tested compounds on the development of microbial biofilms showed that they have an inhibitory effect on microbial adhesion.

Solubility enhancement of Cefpodoxime acid by aqueous solution of paracetamol through acoustical, polarizable continuum model and antimicrobial activity studies

The pharmacological response of an antibiotic depends on the optimum concentration of homogenous solution of the drug and deviation from this may result in major problems with generic and formulation developments of new chemical entities (NCE’s). Further, the introduction of additional new drugs with greater pharmacokinetic activity is limited because of their poor aqueous solubility. In the present work, an attempt has been made to explore the enhancement of solubility and hence the bioavailability or antimicrobial activity of a pharmaceutically significant drug Cefpodoxime acid (CA), a metabolite of third generation cephalosporin antibiotic cefpodoxime proxetil (CP), by the addition of aqueous paracetamol (PA) solution. Ultrasonic investigation has been carried out on the aqueous solutions of PA containing different concentration of CA at ambient and physiological temperatures and at pressure 101.3 kPa. The measured values of ultrasonic velocity, density and dynamic viscosity and the computed acoustical parameters at 303.15 K, 310.15 K and 313.15 K reveal significant intermolecular interactions between unlike drug molecules. The polarizable continuum model (PCM) study for the two drugs in four different solvents is applied in the calculation of free energy of solution (ΔGsol) which provide valid information regarding the mutual solubility of the two drugs and possible enhancement of bioavailability of CA in presence of PA. Antimicrobial activity of CA in the presence of PA in aqueous medium confirms the improvisation of solubility of CA drug. The data obtained through antimicrobial activity studies support the increased pharmacokinetic activity of CA in the presence of PA in aqueous environment.