Potential Antimicrobial Agents Research Articles

Engineering a wolf spider A-family toxin towards increased antimicrobial activity but low toxicity

Spider-derived peptides with insecticidal, antimicrobial and/or cytolytic activities, also known as spider venom antimicrobial peptides (AMPs), can be found in the venoms of RTA-clade spiders. They show translational potential as therapeutic leads. A set of 52 AMPs has been described in the Chinese wolf spider (Lycosa shansia), and many have been shown to exhibit antibacterial effects. Here we explored the potential to enhance their antimicrobial activity using bioengineering. We generated a panel of artificial derivatives of an A-family peptide and screened their activity against selected microbial pathogens, vertebrate cells and insects. In several cases, we increased the antimicrobial activity of the derivatives while retaining the low cytotoxicity of the parental molecule. Furthermore, we injected the peptides into adult Drosophila suzukii and found no evidence of insecticidal effects, confirming the low levels of toxicity. Our data therefore suggest that spider venom linear peptides naturally defend the venom gland against microbial colonization and can be modified into more potent antimicrobial agents that could help to battle infectious diseases in the future.

Organic extracts from sustainable hybrid poplar hairy root cultures as potential natural antimicrobial and antibiofilm agents.

In order to meet growing consumer demands in terms of naturalness, the pharmaceutical, food, and cosmetic industries are looking for active molecules of plant origin. In this context, hairy roots are considered a promising biotechnological system for the sustainable production of compounds of interest. Poplars (genus Populus, family Salicaceae) are trees of ecological interest in temperate alluvial forests and are also cultivated for their industrial timber. Poplar trees also produce specialized metabolites with a wide range of bioactive properties. The present study aimed to assess the hybrid poplar hairy root extracts for antimicrobial and antibiofilm activities against four main life-threatening strains of Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. Ethyl acetate extracts from two hairy root lines (HP15-3 and HP A4-12) showed significant antibacterial properties as confirmed by disc diffusion assay. Antibiofilm activities were found to be dose dependent with significant biofilm inhibition (75-95%) recorded at 1000µg.mL-1 in all the bacterial strains tested. Dose-dependent enhancement in the release of exopolysaccharides was observed in response to treatment with extracts, possibly because of stress and bacterial cell death. Fluorescence microscopy confirmed loss of cell viability of treated bacterial cells concomitant with increased production of reactive oxygen species compared to the untreated control. Overall, this study demonstrates for the first time a high potential of poplar hairy root extracts as a natural and safe platform to produce antimicrobial agents in pharmaceutical, food, industrial water management, or cosmetic industries.

Synthesis of 1,2,3-triazole containing compounds as potential antimicrobial agents

Synthesis of 1,2,3-triazole containing compounds as potential antimicrobial agents

Enhancing Bioactivity through the Transfer of the 2-(Hydroxymethoxy)Vinyl Moiety: Application in the Modification of Tyrosol and Hinokitiol.

Utilizing Density Functional Theory (DFT) calculations at the B3LYP/QZVP level and incorporating the Conductor-like Polarizable Continuum Model (C-PCM) for solvation, the thermodynamic and chemical activity properties of 21-(hydroxymethoxy)henicosadecaenal, identified in cultured freshwater pearls from the mollusk Hyriopsis cumingii, have been elucidated. The study demonstrates that this compound releases formaldehyde, a potent antimicrobial agent, through dehydrogenation and deprotonation processes in both hydrophilic and lipophilic environments. Moreover, this polyenal exhibits strong anti-reductant properties, effectively scavenging free radicals. These critical properties classify the pearl-derived ingredient as a natural multi-functional compound, serving as a coloring, antiradical, and antimicrobial agent. The 2-(hydroxymethoxy)vinyl (HMV) moiety responsible for the formaldehyde release can be transferred to other compounds, thereby enhancing their biological activity. For instance, tyrosol (4-(2-hydroxyethyl)phenol) can be modified by substituting the less active 2-hydroxyethyl group with the active HMV one, and hinokitiol (4-isopropylotropolone) can be functionalized by attaching this moiety to the tropolone ring. A new type of meso-carrier, structurally modeled on pearls, with active substances loaded both in the layers and the mineral part, has been proposed.

Novel ionic polymers encompassing di-cationic pyridinium hydrazones and aromatic ester as potent antimicrobial agents against resistant bacteria

In this work, readily achievable synthetic pathways including quaternization, metathesis and copolymerization reactions were utilized for the construction of a new di-pyridinium monomers and their respected ionic polymers scaffold with ester fragments. All synthesized material were well characterized by spectroscopic experiments. The surface morphology and thermal study of the produced polyesters were carried out using SEM, PXRD, and TGA analysis. The impact of the counter anions on the crystallinity and thermal analysis of the polymer network was confirmed by thermal analysis and surface investigation. The related polyesters' crystallinity was decreased, and their thermal stability was increased by the TFSI anion. Various significant consequences regarding the development of innovative antibacterial agents along with specific therapies. Subsequently, we evaluated the antimicrobial, antibiotic resistant strains, and anti-prophage properties of these novel class of ionic and poly-ionic materials. Throughout antibacterial studies, the M-Br monomer excelled all synthesized materials, although PPy-TFSI and its monomer outperformed antibiotic-resistant organisms. Both M-PF6 and PPy-PF6 decreased S. aureus bacteriophage proliferation. Understanding the bacterial species or strains that are vulnerable to polyesters encourages subsequent studies in this field to focus on creating targeted therapies for illnesses caused by these pathogens.

Total synthesis of [β-HIle]2-nodupetide: effect of ester to amide substitution on its antimicrobial activity.

The increasing prevalence of deaths due to multidrug-resistant bacteria (MDRB) in infectious disease therapy has become a global health concern. This led to the development of new antimicrobial therapeutic agents that can combat resistance to pathogenic bacteria. The utilization of natural peptide compounds as potential antimicrobial agents is very promising. Nodupetide, a cyclodepsipeptide with very strong antimicrobial activity against Pseudomonas aeruginosa was isolated from the fermentation of Nodulisporium sp. Unfortunately, one of its residues (3S,4S)-3-hydroxy-4-methylhexanoic acid (HMHA) is not commercially available and the synthesis strategies applied have not been successful. Hence, we synthesized its cyclopeptide analogue [β-HIle]2-nodupetide by replacing HMHA with isoleucine homologue. A combination of solid- and solution-phase peptide synthesis was successfully carried out to synthesize [β-HIle]2-nodupetide with an overall yield of 10.4%. The substitution of HMHA with β-homoisoleucine (β-HIle) changed the ester bond into an amide bond in nodupetide's backbone. The analogue was considerably inactive against Pseudomonas aeruginosa. It can be concluded that the ester bond is crucial for the antimicrobial activity of nodupetide.

Antimicrobial Therapy in Dentistry: An Evidence-based Review of Pomegranate Fruit Properties

Background: Phytotherapy is characterized by the use of medicinal plants in their different dosage forms. Currently, the use of this alternative medicine has increased. The raw material of herbal medicines consists of organs from medicinal plants (leaves, stems, fruits, peels, flowers and roots) with pharmacological, food, technical or cosmetic adjuvant effects. In addition, the side effects of its use appear to be reduced compared to synthetic and conventional medication. Objective: The aim of this mini-review is to present the scientific evidence involving the properties of the pomegranate fruit for future antimicrobial applications in dentistry. Methods: Literature searches included randomized clinical trials and in vitro studies [2000-2023] filtered mainly by the following terms [Punica granatum L.], [Pomegranate], [Dentistry], [Antimicrobial activity] and [Candida albicans]. Results: Studies have shown that Punica granatum Linn. has considerable antimicrobial activity, in addition to other pharmacological effects such as anti-cancer, antioxidant and antiinflammatory action. The use of herbal medicines, as potent antimicrobial agents against oral pathogens, has been widely reported. Conclusion: The use of P. granatum has proven its effectiveness, as a potent antimicrobial agent against oral pathogens, especially against the fungus Candida albicans, future studies need to focus on the development of a biocompatible formulation directed to the treatment of patients with oral candidiasis.

Pyrimidine-based sulfonamides and acetamides as potent antimicrobial Agents: Synthesis, Computational Studies, and biological assessment

A series of novel sulfonamide and acetamide derivatives of pyrimidine were synthesized and their antimicrobial activities were assessed. Based on the Microbroth dilution method, the minimum inhibitory concentration (MIC) of the synthesized compounds demonstrated moderate to good levels of antifungal and antibacterial activity. Structure-activity relationship analysis suggested that the presence of electron-withdrawing groups, such as halogens, nitrile, and nitro groups, on the pyrimidine ring contributed to the enhanced antimicrobial potency, while electron-donating substituents led to a decrease in activity. Computational studies, including density functional theory (DFT), frontier molecular orbitals (FMO), and molecular electrostatic potential (MEP) analysis, provided insights into the electronic properties and charge distribution of the compounds. Drug-likeness evaluation using ADME/Tox analysis indicated that the synthesized compounds possess favorable physicochemical properties and could be potential drug candidates. Molecular docking against the Mycobacterium TB protein tyrosine phosphatase B (MtbPtpB) revealed that the synthesized compounds exhibited strong binding affinities (−46 kcal/mol to − 61 kcal/mol) and formed stable protein–ligand complexes through hydrogen bonding and π-π stacking interactions with key residues in the active site. The observed interactions from the docking simulations were consistent with the predicted interaction sites identified in the FMO and MEP analyses. These findings suggest that the synthesized pyrimidine derivatives could serve as promising antimicrobial agents and warrant further investigation for drug development.

The synergy effect of matrine and berberine hydrochloride on treating colibacillosis caused by an avian highly pathogenic multidrug-resistant Escherichia coli

Infection by multidrug-resistant avian pathogenic Escherichia coli (APEC) in chickens always leads to the uselessness of antibiotics, highlighting the need for alternative antibacterial agents. Sophora flavescens and Coptis chinensis have been a classical combination used together in Traditional Chinese Medicine (TCM) formulas to treat diseases with similar symptoms to colibacillosis for an extended period, but the effect of their active ingredients' combination on APEC infection remains unstudied. The objective of this study was to explore the synergistic effect of matrine and berberine hydrochloride on colibacillosis caused by an isolated multidrug-resistant APEC. In this study, a highly pathogenic E. coli was isolated from the liver of a diseased chicken in a farm suspected of colibacillosis, and it was resistant to multiple antibiotics. The LD50 of the strain was approximately 3.759×108 CFU/mL. The strain harbored several antibiotic resistance genes and virulence genes. Matrine and berberine hydrochloride have synergistic antibacterial effect against the isolated strain in vitro. The combined use of matrine and berberine hydrochloride exhibited synergistic effects in the treatment of APEC infection by regulating the organ indices, improving the pathological situation, decreasing the bacterial load, and regulating the inflammatory factors to enhance the survival rate of chickens in vivo. These results provided a foundation for revealing the effective effects and possible mechanisms of matrine and berberine hydrochloride as potential antimicrobial agents on diseases caused by multidrug-resistant APEC in chickens.

Transition metal complexes of hydrazones as potential antimicrobial and anticancer agents: A short review.

Hydrazones display an interesting profile of biological activities, which includes mainly antimicrobial and antiproliferative properties. Hydrazones also play an important role in the synthesis of heterocyclic rings and in coordination chemistry. Currently, the synthesis of complexes of hydrazones with transition metals is quite frequently reported in the scientific literature. The interest in this topic is largely due to diverse biological activities of the metal complexes of hydrazones that in some cases are much more effective than hydrazones themselves. This review focuses on the complexes of hydrazones with transition metals which display antibacterial, antitubercular, antifungal and anticancer activities. In the following subchapters devoted to a given activity, an attempt has been made to present the most active complexes of hydrazones, their trends in their activity and application in medicinal chemistry. The paper presents the literature data from 2009 to 2023. This review constitutes a useful guide for the researchers who intend to synthesize and investigate complexes of hydrazones in terms of their antimicrobial and anticancer activities.

A New Guanidine-Core Small-Molecule Compound as a Potential Antimicrobial Agent against Resistant Bacterial Strains.

The guanidine core has been one of the most studied functional groups in medicinal chemistry, and guanylation reactions are powerful tools for synthesizing this kind of compound. In this study, a series of five guanidine-core small molecules were obtained through guanylation reactions. These compounds were then evaluated against three different strains of Escherichia coli, one collection strain from the American Type Culture Collection (ATCC) of E. coli ATCC 35218, and two clinical extended-spectrum beta-lactamase (ESBL)-producing E. coli isolates (ESBL1 and ESBL2). Moreover, three different strains of Pseudomonas aeruginosa were studied, one collection strain of P. aeruginosa ATCC 27853, and two clinical multidrug-resistant isolates (PA24 and PA35). Among Gram-positive strains, three different strains of Staphylococcus aureus, one collection strain of S. aureus ATCC 29213, and two clinical methicillin-resistant S. aureus (MRSA1 and MRSA2) were evaluated. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) experiments were reported, and the drop plate (DP) method was used to determine the number of viable suspended bacteria in a known beaker volume. The results from this assessment suggest that guanidine-core small molecules hold promise as therapeutic alternatives for treating infections caused by clinical Gram-negative and Gram-positive bacteria, highlighting the need for further studies to explore their potential. The results from this assessment suggest that the chemical structure of CAPP4 might serve as the basis for designing more active guanidine-based antimicrobial compounds, highlighting the need for further studies to explore their potential.

Synthesis, Characterization and Antimicrobial Evaluation of New Substituted Thiazolidinones Bearing Triazole Moiety

Series of thiazolidinone derivatives containing triazole moiety have been synthesized by condensing various substituted aldehydes to form Schiff bases which further reacts with thioglycolic acid undergoes ring condensation to form 3-(3-mercapto-5-((5-methoxy-1H-indol-1-yl)methyl)-4H-1,2,4-triazol-4-yl)-2-substituted phenylthiazolidin-4-one followed by reaction with ethyl chloroacetate to form ethyl 2-((4-(2-subtituted phenyl-4-oxothiazolidin-3-yl)-5-((5-methoxy-1H-indol-1-yl)methyl)-4H-1,2,4-triazol-3-yl)thio)acetate. The synthesized compounds were characterized by elemental analysis, fourier-tranform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and mass spectrometry. All synthesized compounds were evaluated for invitro antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and for antifungal activity against Candida albicans, Aspergillus niger. The results of synthesized compounds showed that T-III, T-IX, T-X, and T-XVIII have antimicrobial activity when compared to standard drugs. The compounds having p-bromo, p-chloro, p-methoxy and p-nitro groups showed potent antimicrobial agent

Synthesis, Characterization and Antimicrobial Evaluation of New Substituted Thiazolidinones Bearing Triazole Moiety

Series of thiazolidinone derivatives containing triazole moiety have been synthesized by condensing various substituted aldehydes to form Schiff bases which further reacts with thioglycolic acid undergoes ring condensation to form 3-(3-mercapto-5-((5-methoxy-1H-indol-1-yl)methyl)-4H-1,2,4-triazol-4-yl)-2-substituted phenylthiazolidin-4-one followed by reaction with ethyl chloroacetate to form ethyl 2-((4-(2-subtituted phenyl-4-oxothiazolidin-3-yl)-5-((5-methoxy-1H-indol-1-yl)methyl)-4H-1,2,4-triazol-3-yl)thio)acetate. The synthesized compounds were characterized by elemental analysis, fourier-tranform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and mass spectrometry. All synthesized compounds were evaluated for invitro antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and for antifungal activity against Candida albicans, Aspergillus niger. The results of synthesized compounds showed that T-III, T-IX, T-X, and T-XVIII have antimicrobial activity when compared to standard drugs. The compounds having p-bromo, p-chloro, p-methoxy and p-nitro groups showed potent antimicrobial agent

Modification and Synergistic Studies of a Novel Frog Antimicrobial Peptide against Pseudomonas aeruginosa Biofilms.

The overuse of traditional antibiotics has resulted in bacterial resistance and seriously compromised the therapeutic efficacy of traditional antibiotics, making the exploration of new antimicrobials particularly important. Several studies have shown that bioactive peptides have become an important source of new antimicrobial drugs due to their broad-spectrum antibacterial action and lack of susceptibility to resistance. In this study, a novel bioactive peptide Nigrosin-6VL was characterised from the skin secretion of the golden cross band frog, Odorrana andersonii, by using the 'shotgun' cloning strategy. Modifications on the Rana Box of Nigrosin-6VL revealed its critical role in antimicrobial functions. The peptide analogue, 2170-2R, designed to preserve the Rana Box structure while enhancing cationicity, exhibited improved therapeutic efficacy, particularly against Gram-negative bacteria, with a therapeutic value of 45.27. Synergistic studies demonstrated that 2170-2R inherits the synergistic antimicrobial activities of the parent peptides and effectively enhances the antimicrobial capacity of cefepime and gentamicin against both planktonic cells and biofilms. Specifically, 2170-2R can synergise effectively with cefepime and gentamicin against different strains of P. aeruginosa biofilms. Consequently, 2170-2R holds promise as a potent antimicrobial agent developed to combat infections induced by Pseudomonas aeruginosa.

Mesoporous Oxidized Mn-Ca Nanoparticles as Potential Antimicrobial Agents for Wound Healing.

Managing chronic non-healing wounds presents a significant clinical challenge due to their frequent bacterial infections. Mesoporous silica-based materials possess robust wound-healing capabilities attributed to their renowned antimicrobial properties. The current study details the advancement of mesoporous silicon-loaded MnO and CaO molecules (HMn-Ca) against bacterial infections and chronic non-healing wounds. HMn-Ca was synthesized by reducing manganese chloride and calcium chloride by urotropine solution with mesoporous silicon as the template, thereby transforming the manganese and calcium ions on the framework of mesoporous silicon. The developed HMn-Ca was investigated using scanning electron microscopy (SEM), transmission electron microscope (TEM), ultraviolet-visible (UV-visible), and visible spectrophotometry, followed by the determination of Zeta potential. The production of reactive oxygen species (ROS) was determined by using the 3,3,5,5-tetramethylbenzidine (TMB) oxidation reaction. The wound healing effectiveness of the synthesized HMn-Ca is evaluated in a bacterial-infected mouse model. The loading of MnO and CaO inside mesoporous silicon enhanced the generation of ROS and the capacity of bacterial capture, subsequently decomposing the bacterial membrane, leading to the puncturing of the bacterial membrane, followed by cellular demise. As a result, treatment with HMn-Ca could improve the healing of the bacterial-infected wound, illustrating a straightforward yet potent method for engineering nanozymes tailored for antibacterial therapy.

Efficacy of ozonated olive oil against peri-implant microbes isolated from peri-implantitis.

This study aimed to investigate the antibacterial and antimicrobial activity of ozone gel against oral biofilms grown on titanium dental implant discs. The experiment used medical grade five titanium discs on which peri-implant isolated biofilms were grown. The experimental groups were control, Streptococcus mutans (S. mutans) and Granulicatella adiacens (G. adiacens), (n = 6). The oral microbes grown on titanium discs were exposed to ozone gel for 3 minutes and the antibacterial activity was assessed by turbidity test and adherence test for the antibiofilm activity test. Bacterial morphology and confluence were investigated by scanning electron microscopy (SEM), (n=3). Two bacterial species were identified from the peri-implant sample, S. mutans and G. adiacens. The results showed that adding ozone to the bacterial biofilm on titanium dental implants did not exhibit significant antibacterial activity against S. mutans. Moreover, there was no significant difference in antibiofilm activity between control and treatment groups. However, significant antibacterial and antibiofilm effect was exhibited by ozone gel against G. adiacens. Ozonated olive oil can be considered as a potential antimicrobial agent for disinfecting dental implant surfaces and treating peri-implantitis.

Emodin Alcohols: Design, Synthesis, Biological Evaluation and Multitargeting Studies with DNA, RNA, and HSA.

A series of novel emodin alcohols were designed and prepared in an effort to overcome the increasing microorganism resistance. Novel emodin alcohols were prepared from commercial emodin and different nitrogen-containing heterocycles via different synthetic strategies, such as O-alkylation and N-alkylation. The antimicrobial activity of synthesized emodin compounds was evaluated in vitro by a two-fold serial dilution technique. The interaction of emodin compound 3d with biomolecule was researched using UV-vis spectroscopic method and fluorescence spectroscopy. Emodin compound 3d containing 2-methyl-5-nitro imidazole ring showed relatively good antimicrobial activity. Notably, it exhibited equivalent activity against S. aureus in comparison to the reference drug norfloxacin (MIC = 4 μg/mL). The combination of strong active compound 3d with reference drugs showed better antimicrobial activity with less dosage and a broader antimicrobial spectrum than their separate use. Further research displayed that emodin compound 3d could intercalate into S. aureus DNA to form the 3d-DNA complex, which might correlate with the inhibitory activity. The hydrogen bonds were found between S. aureus DNA gyrase and strong active compound 3d during the docking research, which were in accordance with the spectral experiment results. The interaction with yeast RNA of compound 3d could also form a complex via hydrogen bonds. The hydrogen bonds were found to play a major role in the transportation of emodin compound 3d by human serum albumin (HSA), as confirmed by molecular simulation. This work provides a promising starting point to optimize the structures of emodin derivatives as potent antimicrobial agents.

Click Chemistry; Inspired Synthesis and Antimicrobial Evaluation of 1,2,4-triazolo [4,3-a]pyridine linked 1,4-disubstituted 1,2,3-triazole Derivatives with Amide Functionalities

In an attempt to rationalize the search for new potential antimicrobial agents, a new series of 1,2,4-triazolo[4,3-a] pyridine linked 1,4-disubstituted 1,2,3-triazoleswith amide linkage has been synthesized by the cyclization of 1,2,4-triazolo[4,3-a]pyridine-based alkynes and 2-azido N-phenylacetamide in the presence of CuSO4 as catalyst through ??Click Chemistry" approach. The newly synthesized scaffolds have been evaluated for their antimicrobial potential using eight microbial strains such as Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Bacillus megaterium, Staphylococcus aureus, Bacillus subtilis, Aspergillus Niger, and Aspergillus flavus. Results revealed that all synthesized scaffolds displayed superior activities than the standard drugs against various microbial strains. The synthesized compounds showed potential antimicrobial activity against Gram-positive, Gram-negative bacteria, and fungi.. KEYWORDS :Antimicrobial activity, Click chemistry, Microwave irradiation, 1,4-Disubstituted 1,2,3-triazoles, 1,2,4-Triazolo[4,3-a]pyridine.

An investigation on the photocatalytic and antibacterial response of green fluorescent carbon dots synthesized from corn flour

Abstract The present work elucidates on a facile hydrothermal synthesis method for producing highly fluorescent carbon dots using corn flour as a natural carbon source. The structural confirmation was validated through XRD (X-ray Diffraction), HR-TEM (High-Resolution Transmission Electron Microscope), and FTIR (Fourier Transform Infra-Red) studies. The synthesized carbon dots exhibited an excitation-dependent photoluminescence (PL) emission. The optical band gap of as-synthesized carbon dots was estimated using UV-absorption spectral analysis. The variation in optical and luminescent response of the carbon dot suspension with the rate of centrifugation was also monitored. Furthermore, investigations on the photocatalytic response of as-synthesized carbon dots towards degradation of methylene blue and its activity as a potential antimicrobial agent against Escherichia coli are also presented.

Synthesis and antimicrobial behaviour of NiO/Ag-based material

The main objective of the present work is the green synthesis of NiO and Ag nanoparticles using the leaf extract of Azadirachta indica and the development of NiO/Ag-based nanocomposites via an ultrasonic process. The synthesised NiO/Ag was characterised using different analytical methods and used as an antimicrobial agent against different bacterial and fungal strains. The antimicrobial study was done using the well diffusion method. The FTIR study indicated the presence of O–H, C–H (methylene or methyl), CO, O–H, and Ni–Ag, Ag–O, or Ni–O bonds on the surface of NiO/Ag. The XRD peaks of NiO/Ag were found to be 31.60 (103), 37.30 (111), 38.10 (111), 43.40 (200), 62.90 (220), 76.50 (008), 77.50 (311), and 79.50 (222), respectively. The maximum zones of inhibition were found to be 21.6 (±0.71), 21.2 (±0.69), 17.9 (±0.39), 13.3 (±0.81), and 12.3 (±0.38) mm against Escherichia coli, Staphylococcus aureus, Salmonella enterica, Candida albicans, and Aspergillus niger after incubation periods. On the basis of these findings, we can conclude that NiO/Ag is a potent antimicrobial agent against a variety of bacterial and fungal species.