Temperature-sensitive poly(N-isopropylacrylamide)/polylactic acid/lemon essential oil nanofiber films prepared via different electrospinning processes: Controlled release and preservation effect.

To develop an optimized controlled-release system based on temperature-sensitive poly(N-isopropylacrylamide) (PNIPAAm) nanofibers, we prepared three types of temperature-controlled preservative films. These films were composed of PNIPAAm, polyvinyl alcohol (PVA), polylactic acid (PLA), and lemon essential oil (LEO), and were fabricated using uniaxial, coaxial, and layered spinning techniques. The nanofiber films obtained by layered spinning exhibited a sandwich structure, demonstrating superior physical barrier properties, mechanical strength, and thermal resistance. Fourier-transform infrared spectroscopy confirmed the hydrogen bonding interaction between the polylactic acid/lemon essential oil and PNIPAAm layers. LEO release tests showed that PNIPAAm functions as a temperature-responsive switch, suppressing LEO release below and promoting it above the critical solution temperature. After a sustained release at 40 °C for 5 days, the layered film maintained significant antibacterial activity, effectively extending the shelf life of blackberries to 4 days. Considering its physical barrier, mechanical, and sustained-release properties, the layered film derived from PNIPAAm shows great potential as an intelligent temperature-controlled cling film to effectively extend the freshness of perishable products.

Alpinia Officinarum Hance Essential Oil as Potent Antipseudomonal Agent: Chemical Profile, Antibacterial Activity, and Computational Study.

Alpinia officinarum Hance, is an aromatic and medicinal herb with a very interesting history and prominent chemical and biological prospects. We aimed to investigate the antibacterial activity of Alpinia officinarum essential oil and the preferred molecular targets of its constituents together with their pharmacokinetic properties and toxicity profile. According to GC-MS analysis, eucalyptol was the main compound (27.52%) identified in Alpinia officinarum essential oil, followed by α-terpineol, and ß-sesquiphellandrene. As opposed to the weak antiradical activity estimated by DPPH and ABTS tests, the essential oil caused inhibition of all the bacteria following well-diffusion and microdilution methods, especially the gram-negative Pseudomonas aeruginosa and Escherichia coli. It displayed exceptionally remarkable activity against Pseudomonas aeruginosa by totally inhibiting its growth on the agar plate exceeding the effect of chloramphenicol standard. This bactericidal effect was confirmed by very low MIC and MBC values of 0.82 and 6.562 µg/mL, respectively. The molecular docking showed interesting binding affinity between the major compounds and various drug targets in Pseudomonas aeruginosa, also good pharmacokinetic and toxicity behavior. These encouraging findings are particularly relevant in light of the increasingly pressing challenge to find alternative substances with antibacterial aptitude to address the issue of antibiotic resistance among infectious bacteria.

Electronic structure, global reactivity descriptors and nonlinear optical properties of glycine interacted with ZnO, MgO and CaO for bacterial detection.

Modern laboratory medicine relies on analytical instruments for bacterial detection, focusing on biosensors and optical sensors for early disease diagnosis and treatment. Thus, Density Functional Theory (DFT) was utilized to study the reactivity of glycine interacted with metal oxides (ZnO, MgO, and CaO) for bacterial detection. Total dipole moment (TDM), frontier molecular orbitals (FMOs), FTIR spectroscopic data, electronic transition states, chemical reactivity descriptors, nonlinear optical (NLO) characteristics, and molecular electrostatic potential (MESP) were all investigated at the B3LYP/6-31G(d, p) level using DFT and Time-Dependent DFT (TD-DFT). The Coulomb-attenuating approach (CAM-B3LYP) was utilized to obtain theoretical electronic absorption spectra with the 6-31G(d, p) basis set to be more accurate than alternative quantum chemical calculation approaches, showing good agreement with the experimental data. The TDM and FMO investigation showed that glycine/CaO model has the highest TDM (10.129Debye) and lowest band gap (1.643 eV). The DFT computed IR and the experimental FTIR are consistent. The calculated UV-vis spectra showed a red shift with an increase in polarity following an increase in the absorption wavelength due to the interaction with ZnO, MgO, and CaO. Among the five solvents of water, methanol, ethanol, DMSO and acetone, the water and DMSO enhances the UV-Vis absorption. Glycine/CaO model showed high linear polarizability (14.629 × 10-24esu) and first hyperpolarizability (23.117 × 10-30esu), indicating its potential for nonlinear optical applications. The results showed that all model molecules, particularly glycine/CaO, contribute significantly to the development of materials with potential NLO features for sensor and optoelectronic applications. Additionally, MESP confirmed the increased electronegativity of the studied structures. Additionally, glycine/ZnO nanocomposite was synthesized and characterized using IR and UV-visible spectroscopy to determine their structural and spectroscopic features. It was discovered that there was good agreement between the DFT computed findings and the related experimental data. The antibacterial activity of glycine/ZnO nanocomposites against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa were studied in terms of concentration and time. The results showed that increasing the concentration of glycine/ZnO nanocomposite significantly enhanced its antibacterial efficacy by lowering optical density. Notably, Pseudomonas aeruginosa exhibited lower susceptibility to the nanocomposite compared to S. aureus, requiring higher concentrations for effective bactericidal action. In summary, this study contributes novel insights into the dual functionality of glycine-metal oxide complexes, with significant implications as optical biosensor for microbial detection.

Antibacterial, antioxidant, and anti-giardia properties of the essential oil, hydroalcoholic extract, and green synthesis of the silver nanoparticles of Salvia mirzayanii plant.

In this study, an environmentally-friendly, simple, and low-cost approach was developed for the production of silver nanoparticles (Ag NPs) accelerated by Salvia mirzayanii plant. The identification process involved ultraviolet-visible (UV-Vis) spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM). The UV-Vis spectrum exhibited a peak at 450 nm which is a characteristic surface plasmon resonance of Ag NPs. The XRD and EDS analyses confirmed the crystalline nature and the presence of silver element, while the SEM analysis displayed the production of almost spherical nanoparticles. The FTIR spectrum exhibited that the Ag NPs were functionalized with biomolecules found in the extract, which are involved in the production and stabilization of the NPs. The antibacterial activity of the essential oil, the hydroalcoholic extract and Ag NPs was examined against antibiotic-resistant bacteria, Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli). The anti-Giardia activity was tested on Giardia lamblia cysts at different time intervals. The results exhibited that the MIC values for essential oil, hydroalcoholic extract and Ag NPs against S. aureus were 1.65 µL/mL, 75 mg/mL, and 0.125 mg/mL respectively. The MBC was attained 6.25 µL/mL, 300 mg/mL, and 0.25 mg/mL, for essential oil, hydroalcoholic extract and Ag NPs, respectively. The MIC values for essential oil, hydroalcoholic extract and NPs against E. coli were 3.12 µL/mL, 150 mg/mL, and 0.06 mg/mL, respectively. The MBC was determined to be 50 µL/mL, 300 mg/mL, and 0.25 mg/mL for essential oil, hydroalcoholic extract and Ag NPs, respectively. In addition, the antioxidant activity was determined using the ferric reducing antioxidant power (FRAP) test. The results indicated that the essential oil of this plant exhibited the highest antibacterial and anti-giardial properties, whereas its extract demonstrated the strongest antioxidant properties.

Host heterogeneity in humoral bactericidal activity can be complement independent.

Background: Humoral bactericidal activity was first recognized nearly a century ago. However, the extent of inter-individual heterogeneity and the mechanisms underlying such heterogeneity beyond antibody or complement systems have not been well studied. Methods: The plasma bactericidal activity of five healthy volunteers were tested against 30 strains of Gram-negative uropathogens, Klebsiella pneumoniae and Escherichia coli, associated with bloodstream infections. IgG and IgM titers specific to K. pneumoniae strains KP13883 and KPB1 were measured by ELISA, and complement inhibitor was used to measure the contribution of complement-induced killing. Furthermore, MALDI-TOF mass spectrometry was conducted to determine the metabolomic components of plasma with bactericidal properties in 25 healthy individuals using Bayesian inference of Pearson correlation between peak intensity and colony counts of surviving bacteria. Results: Plasma bactericidal activity varied widely between individuals against various bacterial strains. While individual plasma with higher IgM titers specific to K. pneumoniae strain KP13883 showed more efficient killing of the strain, both IgM and IgG titers for K. pneumoniae strain KPB1 did not correlate well with the killing activity. Complement inhibition assays elucidated that the complement-mediated killing was not responsible for the inter-individual heterogeneity in either isolate. Subsequently, using MALDI-TOF mass spectrometry on plasmas of 25 healthy individuals, we identified several small molecules including gangliosides, pediocins, or saponins as candidates that showed negative correlation between peak intensities and colony forming units of the test bacteria. Conclusion: This is the first study to demonstrate the inter-individual heterogeneity of constitutive innate humoral bactericidal function quantitatively and that the heterogeneity can be independent of antibody or the complement system.

Pharmacophylogenetic insights into Scutellaria strigillosa Hemsl.: chloroplast genome and untargeted metabolomics, quantitative analysis and antibacterial analysis.

Scutellaria strigillosa Hemsl., known for its traditional use in Chinese herbal medicine, is valued for heat-clearing and detoxifying, promoting diuresis, reducing swelling, alleviating pain, and preventing miscarriage. Despite its historical use, comprehensive studies on pharmacophylogenetic analysis, including genetic and chemical profiles and the antimicrobial activity of S. strigillosa are still lacking. Understanding these aspects is crucial for fully realizing its therapeutic potential and ensuring sustainable use. This study aims to elucidate these aspects through comparative genomics, metabolomics, and antimicrobial assays with Scutellaria baicalensis Georgi and Scutellaria barbata D. Don. The chloroplast genome of S. strigillosa was assembled, measuring 152,533 bp, and revealing a high degree of conservation, especially in the protein-coding regions, and identified four regions trnK(UUU)-rps16, trnN(GUU)-trnR(ACG), accD-psaI, psbE-petL) of variability that could serve as phylogenetic markers. The phylogenetic analysis revealed a closer genetic relationship of S. strigillosa with S. tuberifera and S. scordifolia than traditionally classified, suggesting a need for taxonomic reevaluation within the genus. UPLC-Q-TOF-MS analysis in negative ion mode was used to explore the chemical diversity among these species, revealing distinct variations in their chemical compositions. S. strigillosa shared a closer chemical profile with S. barbata, aligning with phylogenetic findings. Metabolomic identification through Progenesis QI software resulted in the tentative identification of 112 metabolites, including a substantial number of flavonoids, diterpenoids, iridoid glycosides, phenylethanoid glycosides, and others. HPLC analysis further detailed the concentrations of 12 actives across the species, highlighting the variation in compound content. S. strigillosa shows antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, similar to S. baicalensis root extracts. This research enhances the understanding of the phylogenetic and phytochemical profiles and the antibacterial activity of S. strigillosa, offering new insights into its medicinal properties. The findings suggest a need for taxonomic reevaluation within the genus and underscore the potential antibacterial activity of S. strigillosa for therapeutic applications. Further studies are encouraged to explore its full medicinal potential and contribute to the sustainable development of Scutellaria species.

Antibacterial effects of human mesenchymal stem cells and their derivatives: a systematic review.

Introduction: The growing problem of antimicrobial resistance (AMR) poses a significant challenge to public health; This is partly due to the lack of advancements in the development of novel antibiotics and the pressing need for alternative treatment options. Mesenchymal stem cells (MSC) possess secretory components that enhance the immune response and peptides that disrupt the bacteria constitution. The isolation of various human tissues has facilitated the investigation of the diverse potentials of MSC and their components. Further research is needed to fully understand the spectrum and efficacy of these elements and their differences. The primary aim of this study was to perform a thorough review of the current literature related to the antimicrobial properties of MSC and their associated components. The objective was to establish an insight into the results and effects of utilizing MSC in relation to bacterial colonization, and to present an overview of previously documented findings. Methods: This systematic literature review was conducted using the PubMed, Embase, and Web of Science databases. Data on the effect of MSC or their derivatives were measured by calculating the percentage of bacterial counts reduction after treatment with MSC in comparison to the control. Results: A total of 3,911 articles were screened, and 31 eligible publications were selected for inclusion in the analysis. In the current systematic review, the majority of the experimental designs showed positive outcomes in terms of bacterial load reduction when MSC or their derivatives were used, with bone marrow being the most effective tissue. The rest of the findings exhibited heterogeneity in the spectrum of outcomes that could be attributed to the effects of using various tissues derived MSC in both in vivo and in vitro studies. Conclusion: The findings of our study indicate the potential antibacterial characteristics of MSC. The direct antimicrobial activity of these cells was demonstrated by our results, which quantitatively showed a decrease in bacterial growth after treatment with MSC. However, additional research is required to clarify the factors that determine the efficacy of their antimicrobial activity and their various components.

Multifunctional nitrogen-sulfur codoped carbon quantum dots: Determining reduced glutathione, broad-spectrum antibacterial activity, and cell imaging.

In this study, nitrogen-sulfur codoped carbon quantum dots (N-S/CQDs) with various functions and properties were synthesized through a one-step method utilizing citric acid and cysteine as reaction substrates. The fluorescence of N-S/CQDs can be specifically quenched by permanganate ion (MnO4 -), and the quenched fluorescence can be recovered by the presence of reduced glutathione (GSH). A fluorescence sensing system based on N-S/CQDs@MnO4 - was developed and successfully applied for the determination of GSH in pharmaceutical preparations. Additionally, N-S/CQDs demonstrated broad-spectrum antibacterial activity, with minimum inhibitory concentrations of 32 µg/ml against Staphylococcus aureus (gram-positive bacterium) and 64 µg/ml against Escherichia coli (gram-negative bacterium). N-S/CQDs also proved effective for cell imaging, exhibiting excellent biocompatibility. These findings underscore the multifunctional characteristics and promising application potential of N-S/CQDs. Furthermore, this study provides a solid foundation for the development of multifunctional carbon quantum dots and the expansion of their applications in various fields.

Active-bromide and surfactant synergy for enhanced microfouling control.

Biofilms are structured microbial communities encased in a matrix of self-produced extracellular polymeric substance (EPS) and pose significant challenges in various industrial cooling systems. A nuclear power plant uses a biocide active-bromide for control of biological growth in its condenser cooling system. This study is aimed at evaluating the anti-bacterial and anti-biofilm efficacy of active-bromide against planktonic and biofilm-forming bacteria that are commonly encountered in seawater cooling systems. The results demonstrated that active-bromide at the concentration used at the power plant (1 ppm) exhibited minimal killing activity against Pseudomonas aeruginosa planktonic cells. The bacterial cell surface hydrophobicity assay using Staphylococcus aureus and P. aeruginosa indicated that Triton-X 100 significantly decreased the hydrophobicity of planktonic cells, enhancing the susceptibility of the cells to active-bromide. Biofilm inhibition assays revealed limited efficacy of active-bromide at 1 ppm concentration, but significant inhibition at 5 ppm and 10 ppm. However, the addition of a surfactant, Triton-X 100, in combination with 1 ppm active-bromide displayed a synergistic effect, leading to significant biofilm dispersal of pre-formed P. aeruginosa biofilms. This observation was substantiated by epifluorescence microscopy using a live/dead bacterial assay that showed the combination treatment resulted in extensive cell death within the biofilm, as indicated by a marked increase in red fluorescence, compared to treatments with either agent alone. These findings suggest that active bromide alone may be insufficient for microfouling control in the seawater-based condenser cooling system of the power plant. Including a biocompatible surfactant that disrupts established biofilms (microfouling) can significantly improve the efficacy of active bromide treatment.

The Antibacterial Activities and Effects of Baicalin on Ampicillin Resistance of MRSA and Stenotrophomonas maltophilia.

The development of novel antibacterial agents from plant sources is emerging as a successful strategy to combat antibiotic resistance in pathogens. In this study, we systemically investigated the antibacterial activity and underlying mechanisms of baicalin against methicillin-resistant Staphylococcus aureus (MRSA) and Stenotrophomonas maltophilia. Our results showed that baicalin effectively restrained bacterial proliferation, compromised the integrity of cellular membranes, increased membrane permeability, and triggered oxidative stress within bacteria. Transcriptome profiling revealed that baicalin disrupted numerous biological pathways related to antibiotic resistance, biofilm formation, cellular membrane permeability, bacterial virulence, and so on. Furthermore, baicalin demonstrated a synergistic antibacterial effect when combined with ampicillin against both MRSA and S. maltophilia. In conclusion, baicalin proves to be a potent antibacterial agent with significant potential for addressing the challenge of antibiotic resistance in pathogens.

Chitosan nanoparticles loaded with royal jelly: Characterization, antioxidant, antibacterial activities and in vitro digestion.

Nano-embedding has appeared as a feasible technology to improve the high-quality utilization of royal jelly (RJ). Therefore, the ionic gelation method was proposed to prepared chitosan nanoparticles loaded with royal jelly (RJNPs) and the characterization and biological activity of RJNPs were evaluated in this study. Fourier-transform infrared spectroscopy, differential scanning calorimetry and X-ray diffraction results showed that the methyl and methylene groups of royal jelly combine with the amino groups of chitosan (CS) to become an amorphous polymer. In addition, the 48.68 % encapsulation efficiency and 31.90 % loading capacity were obtained under the optimal ratio of 1:1 RJ to CS, and the average particle size was <500 nm. The antioxidant activity of RJNPs gradually increased with the increase of the RJ proportion. Interestingly, the antibacterial activity on gram-positive bacteria was better than gram-negative bacteria. Most important, RJNPs exhibited better stability and digestibility rather than single RJ. Overall, these findings indicated that RJ can be embedded in chitosan, and RJNPs exhibited good thermal stability, antioxidant activity, antibacterial activities and bioavailability, which was important for the development and application of the high-quality utilization of RJ.

Synergistic effects of thermally reduced graphene oxide/zinc oxide composite material on microbial infection for wound healing applications.

Infections originating from pathogenic microorganisms can significantly impede the natural wound-healing process. To address this obstacle, innovative bio-active nanomaterials have been developed to enhance antibacterial capabilities. This study focuses on the preparation of nanocomposites from thermally reduced graphene oxide and zinc oxide (TRGO/ZnO). The hydrothermal method was employed to synthesize these nanocomposites, and their physicochemical properties were comprehensively characterized using X-ray diffraction analysis (XRD), High-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared (FT-IR), Raman spectroscopy, UV-vis, and field-emission scanning electron microscopy (FE-SEM) techniques. Subsequently, the potential of TRGO/ZnO nanocomposites as bio-active materials against wound infection-causing bacteria, including Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, was evaluated. Furthermore, the investigated samples show disrupted bacterial biofilm formation. A reactive oxygen species (ROS) assay was conducted to investigate the mechanism of nanocomposite inhibition against bacteria and for further in-vivo determination of antimicrobial activity. The MTT assay was performed to ensure the safety and biocompatibility of nanocomposite. The results suggest that TRGO/ZnO nanocomposites have the potential to serve as effective bio-active nanomaterials for combating pathogenic microorganisms present in wounds.

Significance of research on natural products from marine-derived Aspergillus species as a source against pathogenic bacteria.

Bacterial infections pose a significant clinical burden on global health. The growing incidence of drug-resistant pathogens highlights the critical necessity to identify and isolate bioactive compounds from marine resources. Marine-derived fungi could provide novel lead compounds against pathogenic bacteria. Due to the particularity of the marine environment, Aspergillus species derived from marine sources have proven to be potent producers of bioactive secondary metabolites and have played a considerable role in advancing drug development. This study reviews the structural diversity and activities against pathogenic bacteria of secondary metabolites isolated from marine-derived Aspergillus species over the past 14 years (January 2010-June 2024), and 337 natural products (including 145 new compounds) were described. The structures were divided into five major categories-terpenoids, nitrogen-containing compounds, polyketides, steroids, and other classes. These antimicrobial metabolites will offer lead compounds to the development and innovation of antimicrobial agents.

Engineering the novel azobenzene-based molecular photoswitches for suppressing bacterial infection through dynamic regulation of biofilm formation.

BACKGROUND: Bacterial biofilm is a strong fortress for bacteria to resist harsh external environments, which can enhance their tolerance and exacerbate the drug/pesticide resistance risk. Currently, photopharmacology provides an advanced approach via precise spatiotemporal control for regulating biological activities by light-controlling the molecular configurations, thereby having enormous potential in the development of drug/pesticides. RESULTS: To further expand the photopharmacology application for discovering new antibiofilm agents, we prepared a series of light-controlled azo-active molecules and explored their photo isomerization, fatigue resistance, and anti-biofilm performance. Furthermore, their mechanisms of inhibiting biofilm formation were systematically investigated. Overall, designed azo-derivative A11 featured excellent anti-Xoo activity with an half-maximal effective concentration (EC50) value of 5.45 µg mL-1, and the EC50 value could be further elevated to 2.19 µg mL-1 after ultraviolet irradiation (converted as cis-configuration). The photo-switching behavior showed that A11 had outstanding anti-fatigue properties. An in-depth analysis of the action mechanism showed that A11 could effectively inhibit biofilm formation and the expression of relevant virulence factors. This performance could be dynamically regulated via loading with private light-switch property. CONCLUSION: In this work, designed light-controlled azo molecules provide a new model for resisting bacterial infection via dynamic regulation of bacterial biofilm formation. © 2024 Society of Chemical Industry.

Biomimetic Scaffolds Regulating the Iron Homeostasis for Remolding Infected Osteogenic Microenvironment.

The treatment of infected bone defects (IBDs) needs simultaneous elimination of infection and acceleration of bone regeneration. One mechanism that hinders the regeneration of IBDs is the iron competition between pathogens and host cells, leading to an iron deficient microenvironment that impairs the innate immune responses. In this work, an in situ modification strategy is proposed for printing iron-active multifunctional scaffolds with iron homeostasis regulation ability for treating IBDs. As a proof-of-concept, ultralong hydroxyapatite (HA) nanowires are modified through in situ growth of a layer of iron gallate (FeGA) followed by incorporation in the poly(lactic-co-glycolic acid) (PLGA) matrix to print biomimetic PLGA based composite scaffolds containing FeGA modified HA nanowires (FeGA-HA@PLGA). The photothermal effect of FeGA endows the scaffolds with excellent antibacterial activity. The released iron ions from the FeGA-HA@PLGA help restore the iron homeostasis microenvironment, thereby promoting anti-inflammatory, angiogenesis and osteogenic differentiation. The transcriptomic analysis shows that FeGA-HA@PLGA scaffolds exert anti-inflammatory and pro-osteogenic differentiation by activating NF-κB, MAPK and PI3K-AKT signaling pathways. Animal experiments confirm the excellent bone repair performance of FeGA-HA@PLGA scaffolds for IBDs, suggesting the promising prospect of iron homeostasis regulation therapy in future clinical applications.

Antibacterial Activity and Randomised Controlled Trial of Chlorhexidine-Coated Floss on Gingival Bleeding.

INTRODUCTION: While Chlorhexidine mouthwash is widely studied for the treatment of periodontal disease, research on chlorhexidine in the form of dental floss is limited. This study aims to evaluate the effect of chlorhexidine wax-coated dental floss on dental plaque accumulation and gingival bleeding. Additionally, antibacterial activity and cellular toxicity were also investigated in vitro. METHODS: Various concentrations of chlorhexidine wax-coated floss (0%, 0.12%, 1%, and 2%) were prepared. The antibacterial activity against Streptococcus mutans was studied using a disc diffusion assay. Cellular toxicity was assessed in L929 cells and human gingival fibroblasts using an MTT assay. To evaluate the effects on plaque accumulation and gingival bleeding, 27 participants were randomly divided into 3 groups: 1) 0% chlorhexidine wax-coated dental floss (control), 2) 0.12% chlorhexidine wax-coated dental floss, and 3) 1% chlorhexidine wax-coated dental floss. All participants were instructed to use the provided dental floss once daily at bedtime for 14 days. Six sites per tooth were evaluated for the Quigley-Hein plaque index and bleeding index (BI) at day 0 (baseline) and day 15. All fully erupted teeth, except the third molars, were examined. RESULTS: Chlorhexidine-coated floss exhibited antibacterial activity against S. mutans in a dose-dependent manner. In an in-vitro study, a 2% concentration of chlorhexidine in the floss was found to be highly toxic, leading to its exclusion from clinical trials. After 14 days of use, significantly lower levels of BI were observed in the groups using chlorhexidine wax-coated dental floss, compared to the control. Additionally, there was no significant difference in BI between the 0.12% and 1% chlorhexidine wax-coated dental floss groups. However, no significant difference in plaque index was found between the groups using chlorhexidine wax-coated dental floss and the control group. CONCLUSIONS: This study demonstrated the antibacterial and anti-gingivitis properties of chlorhexidine wax-coated dental floss. Our results showed that using chlorhexidine wax-coated dental floss at a concentration as low as 0.12% could significantly reduce gingival bleeding. However, no additional benefit of chlorhexidine wax-coated dental floss on dental plaque accumulation was found.

Innovative synthesis and molecular modeling of actinomycetes-derived silver nanoparticles for biomedical applications.

The rising demand for innovative antimicrobial solutions has shifted focus towards silver nanoparticles (AgNPs), especially those produced through eco-friendly methods. This study introduces a novel approach utilizing actinomycetes strains-Streptomyces albus, Micromonospora maris, and Arthrobacter crystallopoietes-to biosynthesize AgNPs with remarkable antibacterial properties. Through molecular characterization, we identified unique features of these nanoparticles, and computational modeling suggested significant ion-ligand interactions with proteins 6REV and 3K07. Our research highlights the promise of these biogenically synthesized nanoparticles in advancing biomedical applications. Actinomycetes were sourced and screened for their ability to produce metallic nanoparticles, revealing that among 35 samples, only six showed this capability. Notably, Streptomyces albus strain smmdk14 (OR685674), Micromonospora maris strain smmdk13 (OR685672), and Arthrobacter crystallopoietes strain smmdk12 (OR685674) were identified as effective silver nanoparticle producers. The synthesized nanoparticles demonstrated potent antibacterial activity against common pathogens including E. coli, Pseudomonas aeruginosa, Klebsiella spp., Enterococcus faecalis, Staphylococcus aureus, and Acinetobacter spp. The data obtained from color change observation, UV-visible spectrophotometry, Zeta potential, FTIR spectroscopy, and transmission electron microscopy (TEM) characterized AgNPs potentiality. The nanoparticles were spherical, with sizes ranging from 6.46 nm to 24.7 nm. Optimization of production conditions, comparison of antimicrobial effects with antibiotics, evaluation of potential toxicity, and assessment of wound-healing capabilities were also conducted. The biosynthesized AgNPs exhibited superior antibacterial properties compared to traditional antibiotics and significantly accelerated wound healing by approximately 66.4 % in fibroblast cell cultures. Additionally, computational analysis predicted interactions between various metal ions and specific amino acid residues in proteins 6REV and 3K07. Overall, this study demonstrates the successful creation of AgNPs with notable antibacterial and wound-healing properties, underscoring their potential for medical applications.

Hidden potential of hydrazinecarboxamides (semicarbazides) as potential antimicrobial agents: A review.

Hydrazinecarboxamides (semicarbazides) are increasingly recognized as a versatile scaffold in developing potential antimicrobial agents. In addition to a brief overview of the synthetic methods to prepare them, this review comprehensively analyses their antimicrobial properties. These derivatives have demonstrated potent activity against a broad spectrum of mycobacteria, bacterial and fungal pathogens, highlighting their potential to address critical human health challenges, including neglected diseases, and to combat growing antimicrobial resistance. They have also been investigated for their antiviral and antiparasitic properties. The review also summarizes structure-activity relationships, known mechanisms of action and emphasizes the crucial role of the hydrazinecarboxamide moiety in facilitating interactions with biological targets. The combination of hydrazinecarboxamides with other bioactive scaffolds (primaquine, isoniazid, etc.) has led to an identification of promising drug candidates, including those active against resistant strains, offering a promising approach for future innovations in the field of antimicrobial therapy. Attention is also drawn to limitations of hydrazinecarboxamides (poor physicochemical properties, cytotoxicity to human cells, and insufficient target selectivity), which may hinder their clinical application.

Characterization of exopolysaccharide/potato starch nanocomposite films loading g-C3N4 and Ag and their potential applications in food packaging.

The interest in nanocomposite films incorporating edible ingredients and active nanoparticles has surged due to their potential to enhance food quality and prolong shelf-life. This research focused on developing innovative exopolysaccharides (EPS)/potato starch (PS) nanocomposite films integrated with g-C3N4 and AgNO3. Extensive analysis was conducted to assess the microstructure, physical attributes and antimicrobial properties of these films. Fourier transform infrared (FT-IR) analysis revealed electrostatic and hydrogen bonding interactions within the film components. X-ray diffraction (XRD) and X-ray photoelectron spectrometer (XPS) data indicated a high level of compatibility among EPS, PS, g-C3N4, and AgNO3, with no new absorption peaks or characteristic signals of C3N4 and Ag appearing in the nanocomposite films patterns. The thickness, water solubility and water vapor permeability (WVP) of the EPS-PS-C3N4-Ag nanocomposite film increased due to the addition of g-C3N4, reached 0.31 ±â€¯0.03 nm, 36.61 ±â€¯1.76 % and 1.42 ±â€¯0.34 × 10-10 g-1 s-1 Pa-1, respectively. While transparency, swelling degree, and oxygen permeability (OP) significantly decreased, reached 26.18 ±â€¯2.38 %, 63.01 ±â€¯2.51 % and 41.98 ±â€¯1.28 %, respectively. Scanning electron microscopy (SEM) and atomic force microscope (AFM) images depicted an augmented roughness and porosity on the film surface upon integration of g-C3N4 and AgNO3. Moreover, the EPS-PS-C3N4-Ag nanocomposite film displayed enhanced mechanical strength due to the presence of g-C3N4. The melting temperature (Tm) of EPS-PS-C3N4-Ag nanocomposite film was 313.3 °C, the removal rates of DPPH and ABTS was 66.11 ±â€¯2.87 % and 45.09 ±â€¯1.23 % respectively. Significant inhibition of microbial growth was observed in film containing g-C3N4 and AgNO3, which demonstrated no toxicity towards NIH-33 cells, suggesting their potential application as promising active packaging material for food preservation.

Facile construction of Mo-based nanozyme system via ZIF-8 templating with enhanced catalytic efficiency and antibacterial performance.

Although Zeolitic Imidazolate Framework-8 (ZIF-8) shows significant promise in chemodynamic therapy of bacterial infections due to its large specific surface area and enzyme-like activity, it still faces a considerable gap compared to natural enzymes. The dependency on low pH and high concentrations of hydrogen peroxide ((H2O2) is a major factor limiting the clinical progress of nanozymes. Single-atom nanozymes (SA-zyme), which exhibit superior catalytic performance, are expected to overcome this limitation. In this study, we used ZIF-8 as a template to prepare structurally regular molybdenum-based single-atom nanozymes (Mo-zyme) by coordinating molybdenum atoms with nitrogen atoms within the zeolitic imidazolate framework and evaporating the zinc element at high temperatures. The cascade catalytic performance of the nanodrugs was enhanced by loading glucose oxidase (GOx) and encapsulating it with a hyaluronic acid (HA) layer to form a composite (Mo/GOx@HA). Upon contact with hyaluronidase from bacteria in infected tissues, the cascade reaction is triggered, resulting in the degradation of the HA shell, and releasing the encapsulated GOx. Once exposed, GOx catalyzes the oxidation of glucose into gluconic acid, resulting in a localized decrease in pH and continuous production of H2O2. The combination of lowered pH and increased H2O2 concentration significantly amplifies the catalytic activity of the Mo-zyme. This enhanced activity facilitates the in situ generation of hydroxyl radicals (•OH) on the bacterial surface, leading to effective and efficient bacterial eradication. Wound infection treatment has demonstrated that the as-prepared Mo/GOx@HA exhibits excellent antibacterial and anti-inflammatory activity. This work provided a promising enzymatic cascade reaction nanoplatform for the treatment of bacteria infected wounds.