Search Results (395)

Background: The aim of this review is to summarize and evaluate the properties of antibacterial polysaccharides for application in dental implantology to identify knowledge gaps and provide new research ideas. Methods: The electronic databases PubMed, Medline, ProQuest, and Google Scholar were used to search for peer-reviewed scientific publications published between 2018 and 2025 that provide insights to answer research questions on the role of antibacterial polysaccharides in combating pathogens in dental implantology without triggering immune reactions and inflammation. Further research questions relate to the efficacy against various dental pathogens and the understanding of the antibacterial mechanism, which may enable the development of functionalized polysaccharides with long-term antibacterial activity. Results: Biomedical implants have revolutionized medicine but also increased the risk of infections. Implant infections are a major problem in implantology and lead to implant failure and replacement. An antibacterial coating could be an excellent strategy to extend the lifespan of implants and improve the quality of the patient’s life. Bacterial resistance to antibiotics poses significant challenges for researchers, forcing them to search for new ways to prevent bacterial infections in implantology. Antibacterial natural polymers have recently received considerable research attention due to their long-term antibacterial activity. Polysaccharides from marine sources, such as chitosan and alginate, or pectin, xanthan, etc., from various plants, appear to be promising biopolymers for such applications in implantology due to their antibacterial activity, biocompatibility, and osteogenic properties. The antibacterial activity of these natural biopolymers depends on their chemical and physical properties. Nanopolysaccharides exhibit higher antibacterial activity than conventional polysaccharides, but their toxicity to human cells must be considered. Their antibacterial activity is based on the disruption of bacterial DNA or RNA synthesis, increased cell wall permeability, membrane disruption, and cytoplasmic leakage. Conclusions: Polysaccharides are a class of natural polymers with a broad spectrum of biological activities. They exhibit antioxidant, immunomodulatory, anticoagulant, anticancer, anti-inflammatory, antibacterial, and antiviral activity. Furthermore, polysaccharides are non-cytotoxic and exhibit good biocompatibility with osteogenic cells. Bactericidal polysaccharides are attractive new antibacterial materials against implant infections and open up new perspectives in implantology. Full article

In recent years, most of the populations of the world have been using herbal materials for their strong antimicrobial properties and major health benefits. The objective of this study was to evaluate the phenolic profile, as well as the antioxidant and antimicrobial activities, of a dietary supplement composed of extracts from hibiscus (Hibiscus sabdariffa L.) calyces and lemon verbena (Lippia citriodora) leaves (Metabolaid^®, Patent P201731147) mixed at a weight ratio of 35:65 (w/w), respectively. The bioactive components of the methanolic extract were analyzed by UHPLC-ESI-MS/MS. The antioxidant activity was evaluated using spectrophotometric methods, while the antimicrobial activity was assessed through the microdilution method against selected Gram-negative and Gram-positive bacteria. The total phenols content resulted in being 256.10 ± 2.26 mg GAE/g f.w., the flavonoid content was 48.90 ± 2.95 mg CE/g f.w., flavonols were 60.17 ± 7.68 mg QE/g f.w., and anthocyanins were 3.78 ± 0.17 mg C3GE/g f.w. The FRAP value, observed in the natural mix additive, was 1.25 ± 0.03 mg Fe²⁺/g f.w., while the ORAC showed the value of 1893.77 ± 30.39 µmol TE/g f.w. and the DPPH was 23.33 ± 4.12 µg/mL. We found eight phenolic acids, seven flavonols, five anthocyanins, and nine other phenolic compounds. The extract showed a minimum inhibitory concentration (MIC) of 12.5 mg/mL against E. coli, E. aerogenes, and E. faecalis and of 25 mg/mL against S. enterica ser. Typhimurium and S. aureus and a minimum bactericidal concentration (MBC) of 25 mg/mL against E. coli, E. aerogenes, and E. faecalis and of 50 mg/mL against S. enterica ser. Typhimurium and S. aureus. In conclusion, our findings demonstrate that Metabolaid^® is a rich source of bioactive compounds and provides beneficial effects against oxidative stress and pathogenic bacteria, supporting its nutraceutical potential. Full article

Green-synthesized metal nanoparticles show promise in nanomedicine and material engineering. In this study, the polysaccharide of Zingiber officinale (ZOP) was used as a raw material. Through single-factor experiments and a response surface methodology, the optimum synthesis protocol of Zingiber officinale polysaccharide silver nanoparticles (ZOP-NPs-AgNPs) was determined as follows: V(AgNO₃):V(ZOP) = 2.98:1, 59.79 °C, 3 h, pH 9, and 20 mL NaCl, achieving a 92.51% silver chelation rate. Structure analysis revealed that ZOP-NPs-AgNPs were spherical or quasi-spherical, with a particle size < 20 nm and a face-centered cubic crystal structure, which has good thermal stability. Subsequent studies explored the antibacterial and immunomodulatory effects of ZOP-NPs-AgNPs. The minimum inhibitory concentration (MIC) of ZOP-NPs-AgNPs against Escherichia coli and Staphylococcus aureus was determined to be 0.5000 mg/mL and 0.0310 mg/mL, respectively, while the minimum bactericidal concentration (MBC) was 0.5000 mg/mL and 0.0310 mg/mL, respectively. Additionally, ZOP-NPs-AgNPs significantly enhance RAW264.7 cell proliferation and phagocytosis and boost IL−1β, IL−6, NO, and TNF-α production. This confirms that ZOP can act as a green reductant and stabilizer, offering a new method for green nano-silver synthesis. This provides a sustainable way to produce antibacterial products and functional foods, and offers useful references for eco-friendly nano-silver applications. Full article

Multifunctional water-treatment materials urgently need to be developed to avoid normal organic matter, inorganic anions, resistant bacteria, and hazardous disinfection by-products in conventional drinking water treatment strategies. While quaternary ammonium pyridine resins (QAPRs) possess porous adsorption structures and incorporate antibacterial groups, enabling simultaneous water disinfection and purification, their limited bactericidal efficacy hinders broader utilization. Therefore, a deeper understanding of the structure-dependent antimicrobial mechanism in QAPRs is crucial for improving their antibacterial performance. Hexyl (C₆) was proved to be the optimal antibacterial alkyl in the QAPRs. A new antibacterial quaternary ammonium pyridine resin Py-61 was prepared by more surficial bactericidal N⁺ groups and higher efficient antibacterial hexyl, performing with the excellent antibacterial efficiency of 99.995%, far higher than the traditional resin Py-6C (89.53%). The antibacterial resin Py-61 completed the disinfection of sand-filtered water independently to produce safe drinking water, removing the viable bacteria from 3600 to 17 CFU/mL, which meets the drinking water standard of China in GB5749-2022 (<100 CFU/mL). Meanwhile, the contaminants in sand-filtered water were obviously removed by the resin Py-61, including anions and dissolved organic matter (DOM). The resin Py-61 can be regenerated by 15% NaCl solution, and keeps the reused antibacterial efficiency of >99.97%. As an integrated disinfection–purification solution, the novel antibacterial resin presents a promising alternative for enhancing safety in drinking water treatment. Full article

New materials for additive manufacturing are currently being actively studied, which both have the necessary physicochemical properties and are safe for the environment and living organisms. We have proposed a simple process for the production of composite materials based on a transparent polymethyl methacrylate-like photopolymer resin modified with metallic titanium nanoparticles. Standardized plate samples were printed from the obtained modified photopolymer resins using mask stereolithography with an LED light source array (MSLA), and their mechanical properties were evaluated. Plates were also printed, for which the surface topology, distribution of nanoparticles in the polymer matrix, chemical structure, optical properties, chemical structure, and optical properties were characterized. In the context of the impact on biological systems, the ability of materials to enhance the formation of ROS and affect the main biomacromolecules was demonstrated. At the same time, the developed composite materials inhibit the growth of E. coli bacterial cells, and the bactericidal effect of the surfaces of the obtained materials was shown. Despite the significant antibacterial properties of the synthesized materials, no negative impact on the growth and development of adhesive cultures of eukaryotic cells in vitro was detected. Full article

Klebsiella pneumoniae can acquire resistance mechanisms to colistin and present a pan-resistant phenotype. Therefore, new alternative agents are imperative to control this pathogen, and the peptide Jelleine-I stands out as a promising prototype. Here, the antibacterial activity of Jelleine-I against clinical isolates of colistin-resistant K. pneumoniae (CRKP) was investigated. Antimicrobial activity was assessed by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time kill-curve assay. The release of 260 nm-absorbing materials (DNA/RNA) and the release of proteins were used in the lysis assay. Anti-biofilm activity was studied in microplates. In vivo activity was determined by the lethality assay using Tenebrio molitor larvae. The results show that the MIC of Jelleine-I ranged from 16 to 128 µM and the MBC was on average 128 µM. Jelleine-I at 200 µM killed all CRKP cells in suspension (10⁶ colony-forming units (CFU)/mL) after 150 min of incubation. Jelleine-I acts on the CRKP cell membrane inducing lysis. Biomass and viability of CRKP-induced biofilms are reduced after treatment with Jelleine-I, and the use of this peptide in T. molitor larvae infected with CRKP reduces lethality and improves overall larval health. In conclusion, Jelleine-I is a potential prototype for the development of new antimicrobial agents. Full article

The aim of combining agents with different antibacterial mechanisms of action is to achieve a combined effect, which could be either the sum of their individual effects or a synergistic effect greater than the sum of these individual contributions. Mathematically, it seems reasonable to use the simple addition of agent efficacy coefficients to simplify calculations. However, this article examines the validity of this simplification in mathematical models by calculating individual and synergistic bactericidal effects using the “black box” model. All agents were characterized according to current laboratory practice. The relative antibacterial efficacy coefficients of silver nanoparticles in a colloid with chitosan succinate (nAg SCC HTZ) and graphene oxide nanoparticles (GO) were determined. In particular, the activity of silver colloid was found to be 0.29 times the bactericidal activity of erythromycin, while the activity of GO was 0.107 times the bactericidal activity of the same antibiotic against Pseudomonas aeruginosa. At the same time, all the agents demonstrated stable bacteriostatic activity and were well described by linear regression. Testing the combined effects of agents did not reveal any drug synergy. Thus, the effect of silver at a given dose, followed by the addition of GO at a bacteriostatic dose, yielded an unreliable response, different from that of the “silver–GO” system at the same simultaneous inhibition doses (p > 0.1). The data obtained can be used to develop novel combined composite materials with bactericidal properties and to predict their characteristics. Full article

The resistance of Staphylococcus aureus to conventional pharmacological treatments has gradually increased. Thus, new therapeutic strategies are needed. Three tricyclic antidepressants (TCAs), amitriptyline (AMT), nortriptyline (NOR), and clomipramine (CLO), stand out with potential in this regard. Thus, the objective of this study was to evaluate the antibacterial activity of TCAs against S. aureus. The methodology used broth microdilution, checkerboard, flow cytometry, fluorescence microscopy, and scanning electron microscopy (SEM) techniques. The results showed that the minimum inhibitory concentration (MIC) of AMT was 256 µg/mL, while the MIC of NOR was 128 µg/mL, and the MIC of CLO was between 64 and 128 µg/mL. The TCAs exhibited bactericidal activity. In the analysis of the association with oxacillin (OXA), AMT exhibited 75% synergism, while NOR and CLO obtained 62.5%. In combination with vancomycin (VAN), AMT and NOR presented 100% additive interactions, while CLO exhibited 62.5% indifferent interactions. The mechanism of TCAs, isolated and combined with OXA, was associated with a reduction in cell viability, resulting from their action on the bacterial genetic material and generation of oxidative stress. Furthermore, the action of the drugs produced intense morphological changes in the bacterial cells. In conclusion, TCAs are a potential alternative for antistaphylococcal therapy. Full article

One of the most interesting and poorly studied carriers of medicinal substances is the polymer clay composite material (PCCM). Bentonite clays are used in pharmacy for the manufacturing of various dosage forms, as well as in the adsorption of drugs to slow their release. Polymer–clay nanocomposites have demonstrated significantly improved properties compared to pure polymers. A review of recent scientific advances has shown promising results regarding the application of polymer–clay materials in medicine and bioengineering, particularly in the development of carrier sorbents with prolonged action for controlled drug release. As a result, interest in polymer–clay systems is steadily growing and gaining momentum. This paper focuses on the structure and properties of bentonite clays, including their sorption, ion exchange, binding, and rheological properties. The methods for preparing intercalated and exfoliated nanocomposites, such as radical intercalative polymerization in situ on clay surfaces, are reviewed. Furthermore, the improved efficacy and exposure times of PCCMs, combined with their enhanced bactericidal properties, are analyzed for the creation of universal and multifunctional preparations for medical use. Full article

Microbial contamination and biofilm formation on food contact materials (FCMs) represent critical challenges within the food supply chain, compromising food safety and quality while increasing the risk of foodborne illnesses. Traditional materials often lack sufficient microbial resistance to contamination, creating a high demand for innovative antimicrobial surfaces. This study assessed the effectiveness of a nanosized deposited SiO_xC_yH_z coating approved for food contact on 3D-printed polyamide 12 (PA12) disk substrates, aiming at providing antimicrobial and anti-biofilm functionality to mechanical components and packaging material in the food supply chain. The coating was applied using plasma-enhanced chemical vapor deposition (PECVD) and characterized through Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and contact angle measurements. Coated PA12 samples exhibited significantly enhanced hydrophobicity, with an average water contact angle of 112.9°, thus improving antibacterial performance by markedly reducing bacterial adhesion. Microbiological assays revealed a significant (p < 0.001) bactericidal activity (up to 4 logarithms after 4 h, ≥99.99%) against Gram-positive and Gram-negative bacteria, including notable foodborne pathogens such as L. monocytogenes, S. aureus, E. coli, and S. typhimurium. SiO_xC_yH_z-coated PA12 surfaces exhibited strong antibacterial activity, representing a promising approach for coating additive-manufactured components and equipment for packaging production in the food and pharmaceutical supply chain able to enhance safety, extend product shelf life, and reduce reliance on chemical sanitizers. Full article

This work describes the application of three different AgBr heterojunctions with TiO₂, SnO₂ and WO₃ in the treatment of two water sources: wastewater from a dairy industry facility (WDI) and water from a polluted river (WPR). All heterojunctions were widely characterised, and it was observed that the physicochemical properties of all the coupled materials were similar; however, the highest elimination of Enterobacteriaceae (>90%) was obtained with the AgBr/WO₃(20%) photocatalyst in WDI. Under the same conditions, with this photocatalyst, the complete removal of bacteria (i.e., E. coli, total coliforms and other Enterobacteriaceae) was achieved in WPR. The chlorides, hardness and colour in the two water samples decreased after photocatalytic treatment with all the coupled materials. However, nitrate levels and chemical oxygen demand increased due to the possible formation of intermediary species from the photodegradation of organic pollutants and the release of metabolic intermediates from bacterial degradation during the photocatalytic process. Overall, heterogeneous photocatalysis based on AgBr-coupled materials shows potential as a tertiary treatment for WDI and for the purification of vegetable irrigation water. However, it is still important to consider the need to optimise the integrity of photocatalytic materials in order to maintain their bactericidal effectiveness through continuous reuse. Full article

In this study, Bi₂MoO₆ nanoflowers with different molybdenum sources were in situ grown on the surface of g-C₃N₄ nanosheets (OCN) by a simple one-step solvothermal method. The effects of doping and different molybdenum sources on the photocatalytic degradation and bactericidal activity of Bi₂MoO₆/OCN were discussed. Among them, the solvothermal preparation of P-Bi₂MoO₆/OCN using phosphomolybdic acid as molybdenum source can make up for the shortcomings caused by the destruction of OCN structure by generating more lattice defects to promote charge separation and constructing Lewis acid/base sites to effectively improve the photocatalytic performance. In addition, by adding phosphoric acid to increase the P-doped content, more exposed alkaline active sites are induced on the surface of P-Bi₂MoO₆/OCN, as well as larger specific surface area and charge transfer efficiency, which further improve the photocatalytic performance. Finally, the optimized 16P-Bi₂MoO₆/OCN showed a degradation rate of 99.7% for 20 mg/L rhodamine B (RhB) within 80 min under visible light, and the antibacterial rates against E. coli, S. aureus and P. aeruginosa within 300 min were 99.58%, 98.20% and 97.48%, respectively. This study provides a reference for optimizing the synthesis of environmentally friendly, solar-responsive, photocatalytic sterilization materials from the perspective of preparation, raw materials and structure. Full article

Food spoilage caused by microbial contamination remains a global challenge, driving demand for sustainable antibacterial packaging. Conventional photocatalytic materials suffer from limited spectral response, rapid charge recombination, and insufficient reactive oxygen species (ROS) generation under visible light. Here, a Z-scheme heterojunction was constructed by coupling zeolitic imidazolate framework-8 (ZIF-8) with Ag₃PO₄, achieving dual-spectral absorption and spatial charge separation. The directional electron transfer from Ag₃PO₄’s conduction band to ZIF-8 effectively suppresses electron-hole recombination, prolonging carrier lifetimes and amplifying ROS production (·O₂⁻/·OH). Synergy with Ag⁺ release further enhances bactericidal efficacy. Incorporated into a cellulose acetate matrix (CAM), the ZIF-8/Ag₃PO₄/CAM film demonstrates 99.06% antibacterial efficiency against meat surface microbiota under simulated sunlight, alongside high transparency. This study proposes a Z-scheme heterojunction strategy to maximize ROS generation efficiency and demonstrates a scalable fabrication approach for active food packaging materials, effectively targeting microbial contamination control and shelf-life prolongation. Full article

Black phosphorus (BP) nanoflakes have attracted interest as an antimicrobial material for wound healing and implant-associated infections due to their bactericidal activity without the use of antibiotics. Hydrogels are frequently used as a delivery system; however, most research uses photonic activation in the form of near-infrared (NIR) laser stimulation to cause rapid BP degradation, reactive oxygen species (ROS) generation, and a localized photothermal effect. For implant-coating applications, using NIR laser stimulation could be challenging in practice, especially for porous orthopedic implants. This article investigates whether BP nanoflakes, suspended in Pluronic F127 (F127) hydrogels, remain effective against Staphylococcus aureus without photonic activation. The experimental results showed 89.4 ± 7.6% bacterial inhibition from BP nanoflakes at a 5120 µg/mL concentration via passive diffusion in F127; however, it could not kill all the bacteria present. It is hypothesized that the F127 gel interface could create a barrier between the bacteria, which continue to multiply in media, and the antimicrobial black phosphorus compound, which degrades in the F127. Full article

Both synthetic and natural rubber-like elastomers are widely employed in industrial applications (such as tires, seals, protective gloves, and damping absorbers) as well as in the food and animal husbandry industries. These materials should be regularly checked for contamination and the associated infectious risk since they frequently come into contact with food, animals, and people. Additionally, they could act as vehicle of microbes and, as a result, diseases. This pilot study investigates the antibacterial efficacy of novel elastomer formulations against Salmonella enterica subsp. enterica serovar Enteritidis and Legionella pneumophila, with possible applications in drinking water distribution systems (DWDSs). This study aims to evaluate the antimicrobial activity of two rubber and five silicone patented elastomers with antibacterial additives. Two microbiological concentrations (10³ and 10⁴ CFU/mL) were used to compare the efficacy of the elastomers. The results showed a significant decrease in bacterial load in several silicone formulations, with two of them showing the strongest bactericidal efficacy against L. pneumophila (0% and 3% survival rates for VMQ105 and VMQ500L formulations, respectively), despite the wide variations in S. Enteritidis inhibition. One rubber elastomer performed better than the other in terms of reducing bacterial survival for both pathogens (NBRCA) while NBROM showed a 0% survival rate only for L. pneumophila. The findings suggest that certain elastomer compositions might lessen the potential infectious risks in water systems or contaminated matrices. Future research may investigate in situ applications, particularly in hospitals or dental offices where these pathogens pose major health risks. Full article