Antimicrobial Efficacy Research Articles

Biosynthesized silver nanoparticles prevent bacterial infection in chicken egg model and mitigate biofilm formation on medical catheters.

Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications.

Antimicrobial efficacy of direct air gas soft jet plasma for the in vitro reduction of oral bacterial biofilms

The aim of this study was to evaluate the antimicrobial efficacy of an air gas soft jet CAP for its potential use in removing oral biofilms, given that plasma-based technologies have emerged as promising methods in periodontology. Two types of biofilms were developed, one by Streptococcus mutans UA 159 bacterial strain and the other by a complex mixture of saliva microorganisms isolated from a patient with periodontitis. This latter biofilm was characterized via Next Generation Sequencing to determine the main bacterial phyla. The CAP source was applied at a distance of 6 mm for different time points. A statistically significant reduction of both CFU count and XTT was already detected after 60 s of CAP treatment. CLSM analysis supported CAP effectiveness in killing the microorganisms inside the biofilm and in reducing the thickness of the biofilm matrix. Cytotoxicity tests demonstrated the possible use of CAP without important side effects towards human gingival fibroblasts cell line. The current study showed that CAP treatment was able to significantly reduce preformed biofilms developed by both S. mutans and microorganisms isolated by a saliva sample. Further studies should be conducted on biofilms developed by additional saliva donors to support the potential of this innovative strategy to counteract oral pathogens responsible for periodontal diseases.

Far-UVC (222 nm) irradiation effectively inactivates ssRNA, dsRNA, ssDNA, and dsDNA viruses as compared togermicidal UVC (254 nm).

Ultraviolet-C (UVC) irradiation is being used as an effective approach for the disinfection of pathogenic viruses present in air, surfaces, and water. Recently, far-UVC radiation (222 nm) emitted by KrCl* (krypton-chloride) excimer lamps have been recommended for disinfecting high-risk public spaces to reduce the presence and transmission of infectious viruses owing to limited human health exposure risks as compared to germicidal UVC (254 nm). In this study, the UVC inactivation performances of individual filtered KrCl* excimer lamp (222 nm) and germicidal UVC lamp (254 nm) were determined against four viruses, bacteriophages MS2, Phi6, M13, and T4, having different genome compositions (ssRNA, dsRNA, ssDNA and dsDNA, respectively) and shapes (i.e., spherical (Phi6), linear (M13), and icosahedral (MS2 and T4)). Here, the disinfection efficacies of filtered KrCl* excimer lamp (222 nm) and germicidal UVC lamp (254 nm) were evaluated for highly concentrated virus droplets that mimic the virus-laden droplets released from the infected person and deposited on surfaces as fomites. Filtered KrCl* excimer (222 nm) showed significantly better inactivation against all viruses having different genome compositions and structures compared to germicidal UVC (254 nm). The obtained sensitivity against the filtered KrCl* excimer (222 nm) was found to be in the order, T4 > M13 > Phi6 > MS2 whereas for the germicidal UVC (254 nm) it was T4 > M13 > MS2 > Phi6. These results provide a strong basis to promote the use of filtered KrCl* excimer lamps (222 nm) in disinfecting contagious viruses and to limit the associated disease spread in public places and other high-risk areas.

Rinse, gel, and foam – is there any evidence for a difference in their effectiveness in preventing infections?

BackgroundFollowing publication of the 2009 World Health Organizations Guidelines for Hand Hygiene in Health Care, a debate has emerged regarding the relative antimicrobial efficacy of the different formats (rinse, gel, foam) of ABHRs and their ability to contribute to reduction of healthcare-associated infections (HAIs).MethodsData regarding the in-vivo antimicrobial efficacy of ABHRs and other factors that likely affect their effectiveness in reducing HAIs were reviewed, and a comprehensive review of studies that reported the effectiveness of each of the three ABHR formats to improve hand hygiene compliance and reduce HAIs was conducted.ResultsThe amount of rubbing time it takes for hands to feel dry (dry time) is the major driver of ABHR antimicrobial efficacy. ABHR format is not a major factor, and several studies found that rinse, gel, and foam ABHRs have comparable in-vivo antimicrobial efficacy. Other factors that likely impact the ability of ABHRs to reduce transmission of healthcare-associated pathogens and HAIs include ABHR formulation, the volume applied to hands, aesthetic characteristics, skin tolerance, acceptance by healthcare personnel, and hand hygiene compliance rates. When accompanied by complementary strategies, promoting the use of each of the three ABHR formats has been associated with improvements in hand hygiene compliance rates. A review of 67 studies failed to identify an ABHR format that was significantly more effective in yielding statistically significant reductions in transmission of healthcare-associated pathogens or HAIs.ConclusionsCurrent evidence is insufficient to definitively determine if one ABHR format is more effective in reducing transmission of healthcare-associated pathogens and HAIs. More rigorous studies such as multicenter randomized controlled trials comparing the different formats are needed to establish if one format is significantly more effective in reducing HAIs.

Investigation on antioxidant, antimicrobial, anti-inflammatory, and neuropsychiatry potential of phyto-mediated ZnONPs using Colebrookeaoppositifolia

The present study reports the phyto-mediated synthesis of ZnONPs using methanol extracts and n-Butanol fractions from the roots and leaves of C. oppositifolia. The synthesized nanoparticles were characterized using XRD, FE-SEM, HR-TEM, and XPS techniques to determine their crystallite structure, elemental composition, surface topography, and physio-chemical properties. Furthermore, the biological potential of ZnONPs was evaluated for antioxidant, antimicrobial, anti-inflammatory, and in vitro cytotoxic potential on SH-SY5Y neuroblastoma cell lines. Notably, LEME-ZnONPs exhibited exceptional antioxidant activity with an IC50 of 30.200 μg/mL in the DPPH assay. The antimicrobial efficacy was also remarkable, displaying high maximum activity against bacterial strains, evidenced by zones of inhibition (ZOI) measuring 15.67 ± 0.58 mm (E. coli) and 14.67 ± 0.58 mm (S. aureus) for RTME-ZnONPs, attributable to their small crystallite size. Similarly, against antifungal strains, LEBF-ZnONPs (60.94 ± 0.83 %) and RTBF-ZnONPs (60.85 ± 0.74 %) exhibited potency to inhibit both F. oxysporum and R. necatrix due to their small particle size. Furthermore, LEBF-ZnONPs demonstrated superior anti-inflammatory properties, registering an impressive 98.681 %, outperforming Diclofenac sodium (96.835 %). Importantly, the phyto-mediated ZnONPs exhibited minimal cytotoxicity on SH-SY5Y cell lines at 62.5 μg/mL, a concentration employed as an experimental model to assess neuronal function. The multifaceted applications of phyto-mediated ZnONPs extend across various fields, including pharmaceutical sciences, agriculture, and the treatment of neurological diseases.

Gamma Irradiation-Mediated Alterations in Chemical Composition and Antimicrobial Efficacy of Zubaidi, a Wild Edible Desert Truffle (Terfezia boudieri), with Implications for Pharmaceutical Applications

In exploring the impact of γ-radiation on the biochemical makeup and antimicrobial attributes of Zubaidi truffle (Terfezia boudieri), this study delved into the nuanced interplay between irradiation doses, chemical components, and antimicrobial efficacy. This research scrutinized the influence of γ-radiation on the chemical constitutes and antimicrobial characteristics of Zubaidi truffle (Terfezia boudieri). By applying four distinct doses of γ-radiation (2.5, 5.0, 7.5, and 10 kGy), the study assesses various parameters, including phenols, flavonoids, total and reduced soluble sugars, crude and soluble protein, total amino acids, antioxidant activity, and the susceptibility of examined strains to irradiated and non-irradiated truffle extracts in comparison to standard antibiotics. The findings elucidate that γ-irradiation induces moderate adjustments in the chemical composition, coupled with a dose-dependent escalation in antioxidant activity. Remarkably, irradiated truffle extracts highlight antibiotic efficacy comparable to standard antibiotics, unveiling a nuanced correlation influenced by both radiation dosage and bacterial strain.

The fungicidal effectiveness of 2-Chloro-3-hydrazinylquinoxaline, a newly developed quinoxaline derivative, against Candida species.

Candida represents a prevalent fungal infection, notable for its substantial implications on morbidity and mortality rates. In the landscape of prospective treatments, quinoxaline derivatives emerge as a category of compact compounds exhibiting notable potential in addressing infections. These derivatives showcase promising antimicrobial efficacy coupled with favorable pharmacokinetic and safety characteristics. The central aim of this investigation was to examine the antifungal characteristics of 2-Chloro-3-hydrazinylquinoxaline against diverse strains of Candida and Aspergillus in vitro. Additionally, we endeavored to assess the in vivo efficacy of 2-Chloro-3-hydrazinylquinoxaline using a murine model for oral candidiasis induced by C. albicans cells ATCC 10231. 2-Chloro-3-hydrazinylquinoxaline demonstrated noteworthy effectiveness when tested against various reference strains of Candida species. It exhibited heightened efficacy, particularly against Candida krusei isolates. However, its performance against Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Candida auris isolates exhibited variability. Notably, 2-Chloro-3-hydrazinylquinoxaline manifests variable efficacy against Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus and Aspergillus flavus and no effect against Aspergillus brasiliensis. In a murine model, 2-Chloro-3-hydrazinylquinoxaline exhibited significant efficacy in combating the C. albicans cells ATCC 10231 strain, underscoring its potential as a viable treatment option. 2-Chloro-3-hydrazinylquinoxaline has demonstrated substantial potential in effectively addressing various Candida and Aspergillus species, showcasing dual attributes of antifungal and anti-inflammatory properties. However, to attain a more comprehensive understanding of its therapeutic capabilities, further investigations, incorporating additional tests and experiments, are imperative.

A mechanistic model to predict headspace concentration profile of carvacrol for controlled release packaging

The efficacy of an antimicrobial agent in food packaging depends largely on its concentration profile in the package headspace. In this study, a mechanistic mathematical model was developed to predict the headspace concentration profile of carvacrol, a prominent antimicrobial agent, using the physical principles that govern the movement of carvacrol molecules in a controlled release packaging system. The model and its estimated parameter values were validated using three different sets of gas chromatography measurements—this rigorous process confirms the accuracy and reliability of the model. Advancing beyond existing models, our model enhances the understanding of the dynamics between the concentration profile and its interacting processes including evaporation, adsorption, and gas transmission. It provides packaging developers with a superior alternative to the trial-and-error approach to tailor concentration profiles for optimizing antimicrobial efficacy. It leads to more efficient and better design of controlled release packaging.

A Review on cLF36, a Novel Recombinant Antimicrobial Peptide-Derived Camel Lactoferrin.

Lactoferrin is an antimicrobial peptide (AMP) playing a pivotal role in numerous biological processes. The primary antimicrobial efficacy of lactoferrin is associated with its N-terminal end, which contains various peptides, such as lactoferricin and lactoferrampin. In this context, our research team has developed a refined chimeric 42-mer peptide known as cLF36 over the past few years. This peptide encompasses the complete amino acid sequence of camel lactoferrampin and partial amino acid sequence of lactoferricin. The peptide's activity against human, avian, and plant bacterial pathogens has been assessed using different biological platforms, including prokaryotic (P170 and pET) and eukaryotic (HEK293) expression systems. The peptide positively influenced the growth performance and intestinal morphology of chickens challenged with pathogen bacteria. Computational methods and in vitro studies showed the peptide's antiviral effects against hepatitis C virus, influenza virus, and rotavirus. The chimeric peptide exhibited higher activity against certain tumor cell lines compared to normal cells, which may be attributed to the peptide's interaction with negatively charged glycosaminoglycans on the surface of tumor cells. Importantly, this peptide exhibited no toxicity against host cells and demonstrated remarkable thermal and protease stability in serum. In conclusion, while our investigations suggest that the chimeric peptide, cLF36, may offer potential as a candidate or complementary option to some available antibiotics, antiviral agents, and chemical pesticides, significant uncertainties remain regarding its cost-effectiveness, as well as its pharmacodynamic and pharmacokinetic characteristics, which require further elucidation.

Advancements of eco‐friendly natural antimicrobial agents and their transformative role in sustainable textiles

AbstractIn the face of mounting environmental concerns, the textile industry is undergoing a pivotal transformation, with sustainability at the forefront of innovation. This review focuses on the exploration of natural compounds, renowned for their antimicrobial properties, as viable alternatives to conventional chemical agents that pose significant environmental challenges. It delves into a diverse array of natural sources, including plant extracts, essential oils, and microbial‐derived compounds, which have been identified for their potent antimicrobial efficacy. These natural agents not only demonstrate a broad spectrum of activity against pathogenic microorganisms but also represent a stride towards eco‐friendly textile processing by offering a sustainable substitute for synthetic antimicrobials. The integration of these green antimicrobial agents into textiles is scrutinized, with a particular emphasis on their impact on enhancing fabric functionalities. This includes improvements in durability, wash resistance, and the sustained antimicrobial effectiveness of treated fabrics, without sacrificing environmental integrity. Moreover, the study underscores the potential health benefits of these natural agents, such as a decrease in allergic reactions and skin irritations commonly associated with traditional antimicrobial treatments. The review culminates by highlighting the significant role these eco‐conscious solutions play in revolutionizing antimicrobial textiles, promoting industry‐wide sustainable practices, and catering to the escalating consumer demand for environmentally responsible products.Highlights Provides eco‐friendly and sustainable alternatives in textile processing, offering a greener choice over synthetic options. Enhances fabric functionality while preserving environmental integrity, addressing sustainability concerns throughout production. Improves fabric durability, wash resistance, and long‐lasting efficacy, thereby contributing to superior product performance. Reduces allergic reactions and skin irritations, underscoring the health benefits of eco‐friendly antimicrobial treatments. Promotes sustainable practices, shaping the future of antimicrobial textiles and catering to the growing demand for environmentally conscious consumer choices in the industry.

Synergistic Activity of Noble Trimetallic Nanofluids: Unveiling Unprecedented Antimicrobial Potential and Computational Insights.

Nanofluids hold significant promise in diverse applications, particularly in biomedicine, where noble trimetallic nanofluids outperformed their monometallic counterparts. The composition, morphology, and size of these nanofluids play pivotal roles in their functionality. Controlled synthesis methods have garnered attention, focusing on precise morphology, content, biocompatibility, and versatile chemistry. Understanding how reaction parameters such as time, reducing agents, stabilizers, precursor concentration, temperature, and pH affect size and shape during synthesis is crucial. Trimetallic nanofluids, with their ideal composition, size, surface structure, and synergistic properties, are gaining traction in antimicrobial applications. These nanofluids were tested against seven microorganisms, demonstrating a heightened antimicrobial efficacy. Computational analyses, including molecular docking, dynamics, density functional theory (DFT), molecular electrostatic potential (MESP) analysis, and absorption, distribution, metabolism, elimination, and toxicology studies (ADMET) provided insights into binding interactions, energy, reactivity, and safety profiles, affirming the antimicrobial potential of trimetallic nanofluids. These findings emphasize the importance of controlled synthesis and computational validation in harnessing the unique properties of trimetallic nanofluids for biomedical applications.

Scanning electron microscopic investigation on Chicory tribe (Compositae) botanical sources and their antimicrobial potential.

This study discusses the micro-level structural details of Cichorieae pollen sources elucidated by scanning electron microscopy (SEM) and explains their symmetry and morphometry. The in-depth knowledge from the electron ultrastructure of Asteraceae pollen has provided insights into enhanced pollen morphology, and the antimicrobial significance of species under study presents novel avenues for their natural defense mechanisms in the development of antimicrobial agents. In this research, both quantitative and qualitative features of pollen were examined. The pollen grains are prolate-spheroidal and oblate-spheroidal in shape, characterized by a maximum polar diameter of 55.6-61.0 μm and a maximum equatorial distance of 68.3-74.4 μm. SEM reveals various configurations such as echinate perforate-tectate, psilate, and echino-lophate perforate. The Cichorieae species have significant antimicrobial efficacy and are promising sources for the development of novel antimicrobial drugs with potential implications in pharmaceutical and healthcare industries. SEM analysis of Cichorieae pollens has provided remarkable insights into their unique structures, revealing diverse shapes and surface ornamentations, which can be used for accurate Asteraceae species identification. RESEARCH HIGHLIGHTS: SEM provides unique pollen surface structures and patterns of Chicory pollen grains. Chemical composition of Chicory botanical sources provides valuable information on their potential as antimicrobial agents. SEM imaging reveals specialized fenestrate grain structures of taxonomic importance.

Quorum-quenching enzyme Est816 assisted antibiotics against periodontitis induced by Aggregatibacter actinomycetemcomitans in rats

IntroductionQuorum-quenching enzyme Est816 hydrolyzes the lactone rings of N-acyl homoserine lactones, effectively blocking the biofilm formation and development of Gram-negative bacteria. However, its applications in the oral field is limited. This study aimed to evaluate the efficacy of enzyme Est816 in combination with antibiotics against periodontitis induced by Aggregatibacter actinomycetemcomitans in vitro and in vivo.MethodsThe antimicrobial efficacy of enzyme Est816 in combination with minocycline, metronidazole, and amoxicillin was determined using the minimum inhibitory concentration test. The anti-biofilm effect of enzyme Est816 was assessed using scanning electron microscopy, live/dead bacterial staining, crystal violet staining, and real-time quantitative PCR. Biocompatibility of enzyme Est816 was assessed in human gingival fibroblasts (HGF) by staining. A rat model of periodontitis was established to evaluate the effect of enzyme Est816 combined with minocycline using micro-computed tomography and histological staining.ResultsCompared to minocycline, metronidazole, and amoxicillin treatment alone, simultaneous treatment with enzyme Est816 increased the sensitivity of biofilm bacteria to antibiotics. Enzyme Est816 with minocycline exhibited the highest rate of biofilm clearance and high biocompatibility. Moreover, the combination of enzyme Est816 with antibiotics improved the antibiofilm effects of the antibiotics synergistically, reducing the expression of the virulence factor leukotoxin gene (ltxA) and fimbria-associated gene (rcpA). Likewise, the combination of enzyme Est816 with minocycline exhibited a remarkable inhibitory effect on bone resorption and inflammation damage in a rat model of periodontitis.DiscussionThe combination of enzyme Est816 with antibiotics represents a prospective anti-biofilm strategy with the potential to treat periodontitis.

Antimicrobial effect of plasma-activated water combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce

Plasma-activated water (PAW) is increasingly recognized for its role in mitigating microbial contamination in fresh-cut produce, but its disinfection effectiveness can be limited under certain conditions. Notably, dissolving organic acids in PAW is an effective way to boost its antimicrobial properties through a synergistic effect. This study examined the enhanced antimicrobial efficacy of PAW when combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce. Results demonstrated that PAW combined with tartaric acid showed stronger antimicrobial efficacy than PAW alone (p < 0.05). The addition of tartaric acid to PAW increased the oxidation-reduction potential and lowered the pH, contributing to its superior antimicrobial performance against S. aureus. The underlying antimicrobial mechanisms included the inactivation of Ca2+-Mg2+-ATPase and Na+-K+-ATPase accompanied by damage to bacterial cell membrane, enhanced oxidative damage due to the influx of extracellular reactive oxygen species such as H2O2, the disrupted energy metabolic activities, and the mitigated bacterial defense system constructed by antioxidant enzymes, such as superoxide dismutase and catalase. Furthermore, the synergistic treatment improved the quality of fresh-cut asparagus lettuce by retarding browning, curbing microbial spoilage, and lessening weight loss. The preservation of color was largely due to the decreased activities of polyphenol oxidase and peroxidase, along with controlled chlorophyll degradation. These findings suggest that PAW enhanced with tartaric acid could be a promising, cost-effective disinfection strategy for fresh-cut asparagus lettuce.

In-vitro assessment of biocompatibility and antimicrobial properties of 85S bio-glass and SrTiO3 composites

Strontium-containing ceramics enhance bone healing and graft osseointegration, but bacterial infections may impede the process, risking surgical failure. In this study, we explore the development of composites comprising strontium titanate (SrTiO3) and 85S (85SiO2–10CaO–5P2O5 mol%) bio-glass at varying concentrations using in-vitro tests such as simulated body fluid (SBF), MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide), hemolysis, and antibacterial assays. X-ray diffractogram (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analyses confirm the development of the hydroxyapatite layer after immersing in SBF. Notably, 10 wt% of SrTiO3 in 85S bio-glass (STO_10) exhibits exceptional bone formation properties. Furthermore, MTT assays reveal non-cytotoxicity and high cell proliferation behaviour towards MG_63 cells even after 168 h, particularly for 25 mg/ml of high concentration, and are hemocompatible up to STO_10. Additionally, STO_10 demonstrates a 62 % reduction in the growth of E. coli and a 55 % reduction in S. aureus, highlighting its antimicrobial efficacy. These compelling in-vitro findings unveil the significant potential of STO_10 in the field of bone tissue regeneration.

AgNPs-GO Liquid Bandage is antibacterial and accelerates cutaneous wound healing in mouse model

BackgroundThe liquid bandage is a popular choice for superficial wounds due to its convenient application, comfortable feel, attractive appearance, and waterproof properties. It has gained popularity among consumers in recent years. On the other hand, silver-loaded graphene oxide nanoparticles are composite materials that combine carbon and metal. They possess exceptional performance and well-established manufacturing techniques, and have been extensively studied and developed in various areas such as antimicrobial materials, photocatalysis, and semiconductors. These nanoparticles are commonly used as antimicrobial agents in antimicrobial packaging materials, antimicrobial coatings, and antimicrobial wound dressings. ResultsThe study aimed to develop a new type of liquid bandage that has antimicrobial properties. This was achieved by incorporating silver-loaded graphene oxide nanoparticles into the liquid bandage. We measured various physical properties of the liquid bandage, such as film formation time, water resistance, and breathability, to assess its effectiveness as a bandage. We also conducted in vitro antimicrobial experiments to evaluate the antimicrobial efficacy of the liquid bandage. The results showed that the liquid bandages exhibited some antimicrobial activity, indicating their potential for preventing infection. Furthermore, in vitro cytotoxicity experiments demonstrated that the liquid bandage was non-toxic to cells and had good biocompatibility, suggesting its safety for use on wounds. Finally, in vivo wound healing experiments conducted on mice showed that the liquid bandage effectively promoted wound healing. Overall, this study successfully developed a novel liquid bandage with antimicrobial properties, good biocompatibility, and wound healing capabilities. Significance and NoveltyThe AgNPs-GO liquid bandage is expected to be a valuable tool in the medical field for improving wound treatment. It possesses antimicrobial properties. Additionally, it has good biocompatibility, meaning it is well-suited for use in the body and does not cause harm to cells. This liquid bandage also promotes wound healing, which can lead to faster recovery times for patients. Overall, the AgNPs-GO liquid bandage has the potential to greatly enhance the effectiveness of wound treatment.

Antibacterial activity of silver and gold nanoparticles that have been synthesized by curcumin

The green synthesis of metal nanoparticles with curcumin which is a compound with antibiotic effects, was considered for the synthesis of metal nanoparticles. Gold and silver nanoparticles were synthesized with an average diameter of 19.8 ± 6.2 nm and 29.8 ± 6.4 nm respectively. Both particles represent stability in the physiological environment and after a series of washing procedures to remove unreacted precursors. The antimicrobial efficacy of the synthesized nanoparticles was investigated in different techniques such as disk diffusion, agar well diffusion, minimum inhibitory concentration, and minimum bactericidal concentration tests. The results of both curcumin-coated metal nanoparticles in the disk diffusion test were negative. However, in the agar dilution and MIC tests of antibacterial effect of both nanoparticles on the tested bacteria was observed. The silver nanoparticles had an inhibitory effect on all selected bacteria in the agar dilution (8-256 µg/ml). However, gold nanoparticles had a lower inhibitory effect on the growth of some of the selected bacteria (64-512 µg/ml). In conclusion, silver nanoparticles were more effective than gold nanoparticles in most of the investigated methods.

Real-time monitoring of bacterial inactivating process of tailored bactericidal and antifouling cotton fabric with preserving its physicochemical properties and biocompatibility

Microorganisms present on cotton fabric (CF) significantly affect its wearing comfort and pose potential threats to human health. This is mainly attributed to the porous and hygroscopic nature of CF, which easily adsorbs proteins, oily substances, and mineral salts, creating a favorable environment for microorganism proliferations. The bacteria firmly adhered to CF are difficult to remove by conventional washing, resulting in persistent stains. Furthermore, the mechanisms underlying bacterial interaction with fibers and bacterial inactivation remain to be fully understood. Herein, we synthetized reactive Gemini quaternary ammonium salt (CGQ) and sulfopropylbetaine (CGB) to covalently bind onto CF, thereby engineering a customized antimicrobial and antifouling CF while preserving its physicochemical properties. Real-time monitoring of the bacterial inactivation process was also performed. The antimicrobial efficacy of CF finished with CGQ and CGQ/CGB, employing only 5.0 mg/mL antimicrobial concentration, surpassed 95 % against Escherichia coli and 99 % against Staphylococcus aureus after 50 washes. The loosely adhered bacteria on CGQ/CGB-finished CF can be easily eliminated through conventional washing, resulting in an enduring antimicrobial and antifouling surface. Consequently, we have developed a straightforward strategy for the large-scale production of superior antimicrobial and antifouling CF, presenting a versatile solution with wide applications. Additionally, this method offers an efficient strategy for real-time monitoring of the microorganism inactivation process.

Exploring the structure and dynamics of a fluorescent schiff base (1E,1′E)-1,1′-(1,4-phenylene) bis(N-(4-chlorophenyl) methamine: Synthesis, spectroscopic analysis, thermal, electronic and crystallographic study with biological applications

Schiff bases have emerged as attractive biological agents with a wide range of uses due to the extraordinary physical, chemical, and pharmacological characteristics that they possess. This study focuses on the effective synthesis of a Schiff base that is produced from 4-chloroaniline and terephthaldehyde. The success of this synthesis is supported by a variety of spectroscopic methods and Single crystal XRD analysis. The chemical that was synthesised had significant fluorescence qualities, with measured values at 457.13, 481.49, and 524.15 nm, highlighting the fact that it has the potential to be utilised in a variety of applications within the field. Using thermogravimetric analysis, the thermal stability of the compound was studied, which revealed an excellent stability at 399 °C. Thermal stability is an essential component of compound usefulness. Molecular insights were obtained by the utilisation of Density Functional Theory, which revealed an energy gap of 1.70 electron volts (eV) and electrophilic behaviour in certain atoms. The distribution of charges was brought to light through the use of Mulliken charges and molecular electrostatic potential analysis, which brought attention to the distinctive qualities of the subject molecule. An examination of the electron localization function revealed that the electron density inside carbon, nitrogen, and chlorine atoms had been delocalized. Additionally, the localised orbital locator wave function and reduced density gradient maps offered vital insights into the non-covalent interactions that were taking place within the system under investigation. In the course of the evaluation of antimicrobial efficacy, it was discovered that the chemical exhibited more powerful antibacterial activity against gram-positive B. subtilis than the conventional antibiotic amoxicillin. The antibacterial findings were further supported by molecular docking tests, which involved using particular proteins from the target species. These investigations showed that B. subtilis had a higher affinity for binding. These findings were further validated by molecular dynamic simulations. The synthesised chemical was subjected to in silico toxicity assessment using seven models, which demonstrated its non-irritating properties on the skin and eyes. The extensive analysis that is given here lays the groundwork for more targeted research on novel antibacterial drugs, with a particular focus on the safety, molecular interactions, and effectiveness of these compounds. As a result of the compound's potential applicability in biocompatible antimicrobial formulations, it is a viable candidate for improving the development of antibacterial medicines that are both effective and safe.

Design, Synthesis, Biological Evaluation, and Molecular Docking Studies of Pleuromutilin Derivatives Containing Thiazole.

In this study, we designed and synthesized a series of pleuromutilin derivatives containing thiazole. The in vitro antimicrobial efficacy of these synthesized compounds was examined by using four strains. Compared with tiamulin (MIC = 0.25 μg/mL), compound 14 exhibited potency in inhibiting MRSA growth (MIC = 0.0625 μg/mL) in these derivatives. Meanwhile, the time-killing kinetics further demonstrated that compound 14 could efficiently inhibit the MRSA growth. After exposure at 4 × MIC, the postantibiotic effect (PAE) of compound 14 was 1.29 h. Additionally, in thigh-infected mice, compound 14 exhibited a more potent antibacterial efficacy (-1.78 ± 0.28 log10 CFU/g) in reducing MRSA load compared to tiamulin (-1.21 ± 0.23 log10 CFU/g). Moreover, the MTT assay on RAW 264.7 cells demonstrated that compound 14 (8 μg/mL) had no significant cytotoxicity. Docking studies indicated the strong affinity of compound 14 toward the 50S ribosomal subunit, with a binding free energy of -9.63 kcal/mol. Taken together, it could be deduced that compound 14 was a promising candidate for treating MRSA infections.