Search Results (274)

Long-chain imidazolium-based ionic liquids (ILs) possess a broad-spectrum biological activity and are considered promising antifouling agents for protective coatings. A new hydrophobic IL, 1-dodecyl-3-methylimidazolium dodecylbenzenesulfonate (C₁₂C₁IM-DBS), has been synthesized, and a modified epoxy coating material containing 10, 20, and 30 wt% of this IL was prepared by dissolution of C₁₂C₁IM-DBS in commercial DER 331 epoxy resin, followed by a curing phase with diethylenetriamine. Infrared analysis revealed physicochemical interactions between the hydroxyl groups of the resin and the IL. Spectrophotometric studies showed no release of C₁₂C₁IM-DBS after 30 days of exposure of the modified coatings to water. The plasticizing effect of the IL on the epoxy resin was established by differential scanning calorimetry analysis. The introduction of 10 and 20% C₁₂C₁IM-DBS into DER 331 reduced its glass transition temperature from 122.8 °C to 109.3 and 91.5 °C, respectively. The hardness of epoxy resin decreased by approximately 26% after the introduction of the IL. Moreover, DER 331/C₁₂C₁IM-DBS coatings on steel substrates showed significantly improved impact resistance compared to neat resin. The antibiofilm efficiency of DER 331/C₁₂C₁IM-DBS coatings was evaluated by assessing the capability of two biofilm-forming model strains, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa PA01, to form attached biofilms on the surface. The IL effectively inhibited S. aureus surface-associated biofilm development even at the lowest content of 10%. On the contrary, an approximately 50% inhibition of biofilm metabolic activity was detected for DER 331/C₁₂C₁IM-DBS coatings containing 20% and 30% of the IL. Overall, the results of this study indicate that the hydrophobic IL C₁₂C₁IM-DBS is an efficient modifying additive for epoxy resins, which can significantly improve their operational properties for various industrial applications. Full article

The emergence of antimicrobial resistance and the increasing demand for a healthier lifestyle have set new goals for science and industry. In the search for new, more effective, and environmentally friendly antimicrobial agents, special attention is being paid to natural resources. In this regard, essential oils derived from plants, which are widely used in the cosmetic, food, and pharmaceutical industries, are one of the solutions. In view of the above, this study aims to investigate the biological effects of Abies alba essential oil (AAEO). The chemical profile of AAEO was evaluated by GC/MS analysis, which revealed a high abundance of limonene (52.2%) and α-pinene (36.2%). Antioxidant activity evaluation showed a higher potential of AAEO in scavenging ABTS radical species with an IC₅₀ value of 1.18 ± 0.05 mg/mL. In vitro antimicrobial activity was determined by disc diffusion and minimum inhibitory concentration assays and showed that AAEO was more efficient in inhibiting the growth of G⁺ bacterial species. On contrary, in situ evaluations of antimicrobial effects of AAEO on different food models (strawberry, kiwi, white radish, and beetroot) resulted in more efficient suppression of G⁻ bacterial species. Although AAEO showed low effects on yeasts determined by in vitro methods, in situ investigations showed its higher potential in eradication of Candida yeast. The antibiofilm properties of the AAEO matrix were determined by means of crystal violet assay and MALDI-TOF MS Biotyper analysis against biofilm-forming Salmonella enterica. The analysis performed led to the conclusion that AAEO, when applied prior to biofilm formation, may contribute to the removal of planktonic cells and alter the abiotic surface, thereby reducing the suitability of Salmonella enterica for microbial attachment. Full article

Fermented apple juice (FAJ), a nutrient-dense beverage rich in vitamins, offers multiple health benefits, including improved digestion, enhanced fat metabolism, and sustained energy provision with reduced caloric intake. To advance the development of probiotic-enriched flavored and functional juices, this study establishes Lactiplantibacillus plantarum (L. plantarum) as a safe and effective starter culture for apple juice fermentation. The selected strain exhibited minimal biogenic amine synthesis, producing only 30.55 ± 1.2 mg/L of putrescine and 0.59 ± 0.55 mg/L of cadaverine, while histamine and tyramine were undetectable. Furthermore, the strain demonstrated no hemolytic activity and exhibited robust biofilm-forming capacity, reinforcing its suitability for fermentation applications. An electronic nose analysis revealed that L. plantarum significantly enriched the volatile compound profile of FAJ, leading to an improved flavor profile. The strain also displayed excellent growth adaptability in the apple juice matrix, further optimizing fermentation efficiency and sensory quality. Crucially, 16S rRNA sequencing demonstrated that FAJ specifically restructures the gut microbiota in obese individuals, significantly elevating the relative abundance of beneficial genera, including Enterococcus, Parabacteroides, and Bifidobacterium (p < 0.05). Concurrently, FAJ enhanced glycolytic activity, suggesting a potential role in metabolic regulation. Collectively, these findings confirm that L. plantarum-fermented FAJ combines favorable sensory properties and safety with promising anti-obesity effects mediated through gut microbiome modulation and metabolic pathway activation. This study provides a critical scientific foundation for designing next-generation functional fermented beverages with targeted health benefits. Full article

Active packaging films have been an essential component in food material research to ensure the safe and efficient preservation of food, fruit, and vegetables. The shelf life of fruits and vegetables may likely be extended by covering them with high-performance nanofiber (NF) films. The selection of materials for active packaging film has been a critical factor in preventing food materials from environmental contaminants (microbes) and extending the shelf life. This study aims to develop NF-based materials for cherry tomatoes to prevent fungal and bacterial damage. Bioactive NFs were produced through an electrospinning process using tannic acid (TA) within a polyvinylidene fluoride (PVDF) template. These NFs offer a sustainable alternative to synthetic packaging for food preservation. TA was incorporated into the PVDF matrix at varying concentrations (0.4 to 1.2%). Key parameters, including moisture content, thickness, opacity, water-contact angle, and thermal shrinkage, were assessed. The physicochemical results indicate that the TA NFs are suitable for further shelf-life performance evaluations. The antifungal and antibiofilm activity of the NFs was tested, showing that the TA_1.2 in the PVDF matrix was more effective than other concentrations. Shelf-life tests demonstrated that cherry tomatoes covered with TA_1.2 NFs showed no surface changes for up to 4 days. Importantly, the NFs were confirmed to be non-toxic to normal cells, as evidenced by tests on mouse 3T3-L1 fibroblast cells. In summary, we have developed bioactive NFs composed of TA in a PVDF matrix that enhance the shelf life of cherry tomatoes by preventing bacterial and fungal attacks on the fruit surfaces. Full article

Pseudomonas aeruginosa (P. aeruginosa) is a common antibiotic-resistant pathogen, posing significant public health threats worldwide. It is a major cause of ocular infections, mostly linked to contact lens wear. P. aeruginosa often produces biofilm during infections, and these are also associated with antibiotic resistance. Bacteriophage (phage) therapy is emerging as a promising approach for treating multidrug-resistant P. aeruginosa. Objective: This study aimed to assess the antibiofilm effects of six phages against P. aeruginosa biofilms isolated from patients with corneal infections. Method: This study examined P. aeruginosa strains for their ability to form biofilms using crystal violet assay. Six P. aeruginosa bacteriophages (DiSu1 to DiSu6) were used, which were isolated from sewage water in Melbourne, Australia. Spot tests were used to assess phage sensitivity. The effect of phages against P. aeruginosa strains was determined using time–kill assay and efficiency of plating. The ability of phage to inhibit biofilm formation over 24 h or reduce preformed biofilms was also studied and confirmed using confocal laser scanning microscopy with Live/Dead staining. Result: After 24 h of incubation, all tested P. aeruginosa strains formed moderate to strong biofilms. All P. aeruginosa strains were sensitive to at least four of the six phages. The highest level of bacterial growth inhibition in the liquid infection model was observed when phages were applied at a multiplicity of infection (MOI) of 100. Certain bacteria/phage combinations were able to inhibit biofilm formation over 24 h, with the combination of strain PA235 and phage DiSu3 producing the highest inhibition (83%) at a MOI of 100. This was followed by the combinations of PA223/DiSu3 (56%), and PA225/DiSu5 (52%). For the reduction in preformed biofilms, the best combinations were PA235 (90%), PA221 (61%), and PA213 and PA225 (57% each), all with DiSu3 after 3 h. However, exposing the biofilm with phages for over 24 h appeared to promote phage resistance as there was evidence of biofilm growth, with the only combination still showing a significant reduction being PA221/DiSu3 (58%) at MOI of 100. Conclusions: This study showed that the effect of phages against P. aeruginosa is concentration (MOI) dependent. Phages at higher MOI have the ability to disrupt, inhibit, and reduce P. aeruginosa biofilms. However, prolonged exposure of the biofilm with phages appeared to promote phage resistance. To enhance phage efficacy and address this form of resistance, further studies utilizing phage cocktails or a combination of phages and antibiotics is warranted. Full article

Objectives: Nanosized polymeric micelles (PMs) with an average size of about 80 nm and moderately positive ζ potential, based on an amphiphilic poly(4-methyl-piperazin-1-yl)-propenone)-b-polylactide (PMPP-PLA) block copolymer, were prepared. They were used as platforms for the delivery of bioactive sesquiterpene lactones from Inula helenium L. root extract. Methods: The PMs were characterized with good encapsulation efficiency as a maximum value of 72% was reached at a polymer-to-extract mass ratio of 10:1. The loaded micelles exhibited good colloidal stability. An in vitro release was performed showing a burst release profile. The biocompatibility of the resulting PMs was confirmed by assessing their cytotoxic effect on human keratinocytes in vitro by colorimetric assay and flow cytometry. Results: The systems demonstrated the capability to reduce the biomass of pre-formed Gram-positive and Gram-negative bacterial biofilms. Conclusions: The obtained data clearly determine a trend for a strong combined effect between the PMs and the root extract, distinguishing them with an excellent anti-biofilm potential and prospects for future applications in medical practice. Full article

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) and its biofilm-forming ability underscore the limitations of current antibiotics. In this study, a new compound named tripterhyponoid A was found to effectively combat MRSA, with an MIC of 2.0 μg/mL. It inhibited biofilm formation by downregulating genes related to the quorum sensing (QS) pathway (sarA, agrA, agrB, agrC, agrD, and hld) and eradicated mature biofilms. Furthermore, it induced DNA damage by binding to bacterial DNA, enhancing its efficiency against MRSA. Therefore, its anti-MRSA properties with multiple mechanisms of action make it less prone to developing resistance over 20 days. In addition, it reduced the bacterial load and regulated the levels of inflammatory cytokines IL-6 and IL-10 at the wound site in a mouse skin infection model. This paper provides the first in-depth investigation of the mechanisms of triterpenoids against MRSA by inhibiting the expression of QS system genes and binding to DNA. Full article

Alicyclobacillus acidoterrestris, an acidothermophilic bacterium, is one of the main contaminants in the fruit industry due to its high tolerance to environmental stress and ability to form biofilms. As conventional methods of biofilm elimination may be ineffective, there is a need for safe and sustainable methods for A. acidoterrestris management. The objective of the study was to evaluate the antibiofilm activity of commercial essential oils derived from clove (Syzygium aromaticum (L.) Merr. & Perry), cinnamon (Cinnamomum zeylanicum Blume), and peppermint (Mentha piperita (L.) Huds.) against A. acidoterrestris. The effect of the essential oils on the mature biofilms of fifteen environmental A. acidoterrestris isolates subjected to variable pH values (3.0, 4.0, and 5.5), temperatures (25, 37, and 44 °C), and essential oil concentrations (0.5 MIC, MIC, and 2 MIC compared to planktonic cells) was studied. The essential oils showed significant antibiofilm activity against A. acidoterrestris isolates, with the efficiency of biofilm eradication depending on the strain and environmental parameters such as acidity, culture temperature, type, and concentration of essential oil. The greatest antibiofilm potential was observed for clove essential oil regardless of oil concentrations and environmental conditions. Cinnamon oil exhibited lower activity against the tested A. acidoterrestris strains. Peppermint essential oil showed the weakest antibiofilm ability and did not completely eradicate any strain biofilm of the tested strains. Clove and cinnamon essential oils have the potential to be effective alternatives to synthetic disinfectants directed against A. acidoterrestris grown in the form of biofilms. Full article

Background: Methicillin-resistant Staphylococcus aureus (MRSA) considered under the category of serious threats by the Centers for Disease Control and Prevention (CDC), urges for new antibiotics or alternate strategies to control MRSA. Methods: Ethosome-like liposomes have been developed and characterized using dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Liposomes were confirmed for antibiotics infusion by encapsulation efficiency and release kinetics as well. Further, the antimicrobial potential of liposomes was checked by determination of minimum inhibitory concentrations (MICs), crystal violet assay, and live/dead biofilm eradication assay. Results: The specially designed liposomes consist of amphiphilic molecules, tocopherol, conjugated with ampicillin and, another antibiotic amikacin, loaded in the core. The developed liposomes exhibited good encapsulation efficiency, and sustained release while serving as ideal antibiotic carriers for advanced efficacy along with anti-inflammatory benefits from tocopherol. Conclusively, newly designed liposomes displayed potential antimicrobial activity against MRSA and its complex biofilms. Conclusions: Overall, dual antibiotic-encapsulated liposomes demonstrate the potential to eradicate MRSA and its mature biofilms by dual-targeted action. This could be developed as an efficient anti-infective agent and delivery vehicle for conventional antibiotics to combat MRSA. Full article

Precise separation and antifouling capabilities are critical for the application of membrane separation technology. In this work, we developed a multiplayer layer-by-layer assembly strategy to sequentially deposit tannic acid (TA) and lysozyme (Lys) onto polyethersulfone/iron (PES/Fe) ultrafiltration membrane substrates, enabling the simple and efficient fabrication of a biofouling-resistant loose nanofiltration (LNF) membrane with superior dye/salt separation performance. This approach fully leverages the multifunctionality of TA by exploiting its coordination with Fe³⁺ and non-covalent interactions with Lys. The obtained PES/Fe-TA-Lys LNF membrane exhibits a pure water flux of 57.5 L·m⁻²·h⁻¹, along with exceptional dye rejection rates (98.3% for Congo Red (CR), 99.2% for Methyl Blue (MB), 98.4% for Eriochrome Black T (EBT), and 67.6% for Acid Orange 74 (AO74)) while maintaining minimal salt retention (8.2% for Na₂SO₄, 4.3% for MgSO₄, 3.5% for NaCl, and 2.4% for MgCl₂). The PES/Fe-TA-Lys LNF membrane also displays outstanding antifouling performance against bovine serum albumin (BSA), humic acid (HA), and CR, along with strong biofouling resistance against Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) via synergistic anti-adhesion and biofilm inhibiting effects. This work presents a novel and scalable approach to fabricating biofouling-resistant LNF membranes, offering great potential for dye/salt separation in textile wastewater treatment. Full article

Clinical root canal therapy which takes place through mechanical and chemical strategies is faced with challenges in eliminating bacteria owing to the intricate and curved nature of the root canal system. Moreover, the plaque biofilm within the root canal hinders drug penetration and limits treatment efficacy. Hence, efficient root canal therapy hinges on penetrating into the root canal and overcoming the barriers presented by the plaque biofilms. To penetrate and eradicate biofilms effectively at the root canal, we designed a novel magnetic nanoparticle (MN)-based nanoplatform which was synthesized by the self-polymerization of dopamine on the surface of Fe₃O₄ MNs, and then loaded minocycline through the electrostatic interaction. The therapeutic efficacy of minocycline-loaded magnetic nanoparticles (FDM MNs) under a magnetostatic field was observed by various antibacterial experiments. The synthesized FDM MNs exhibited favorable biocompatibility and robust anti-biofilm efficacy. The designed nanoparticles could effectively navigate biofilms to eradicate bacteria residing deep with the assistance of magnetic force. Furthermore, FDM MNs penetrated into dentin tubules under a magnetic field, effectively disrupting biofilms for deep sterilization. The significant results offered valuable experimental evidence to support the potential clinical utility of magnetic nanoparticles for managing pulpitis and periapical inflammation. Full article

The unique properties of lanthanum oxide nanoparticles (La₂O₃NPs) make them highly suitable for various environmental applications. This study explores the plant-based synthesis of La₂O₃NPs using Drypetes sepiaria as a reducing agent. The synthesized La₂O₃NPs were characterized through a range of spectroscopic and microscopic techniques. Scanning electron microscopy (SEM) revealed that the La₂O₃NPs have an uneven surface and a stony appearance. A morphological analysis indicated that the nanoparticles range in size from 20 to 50 nm. The appreciable band gap energy values were concluded as 5.5 eV. The crystal structure and elemental composition were determined using X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS). The results from the microplate assay method demonstrated enhanced anti-biofilm properties, and photocatalytic tests showed significant dye-degradation capabilities. The degradation efficiency and zone inhibition values of the La₂O₃NPs were found to be 90.12% and 39.18%, respectively. Full article

Background/Objectives. One of the pressing challenges in global public health is the rise in infections caused by carbapenem-resistant Enterobacteriaceae. Growing bacterial drug resistance, coupled with the slow development of new antibiotics, highlights the critical need to explore and develop new broad-spectrum antimicrobial agents able to inhibit bacterial growth efficiently. In recent years, antimicrobial peptides (AMPs) have gained significant attention as a promising alternative to conventional drugs, owing to their antimicrobial potency, low toxicity, and reduced propensity for fostering resistance. Our research aims to investigate the antibacterial ability of three amphibian AMPs, namely Hylin-a1, AR-23, and RV-23, against both antibiotic-sensitive and carbapenem-resistant strains of Escherichia coli and Klebsiella pneumoniae. Methods. A 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) was performed to identify non-cytotoxic concentrations of peptides. A microdilution assay evaluated the antibacterial effect, determining the peptides’ minimum inhibitory concentration (MIC). In addition, the checkerboard test analyzed the compounds’ synergistic effect with meropenem. Results. We demonstrated that peptides with low toxicity profile and resistance to proteolytic activity exhibited strong antibacterial activity, with MIC ranging from 6.25 to 25 μM. The antibiofilm mechanism of action of peptides was also investigated, suggesting that they had a crucial role during the biofilm formation step by inhibiting it. Finally, we highlighted the synergistic effects of peptides with meropenem. Conclusions. Our study identifies Hylin-a1, AR-23, and RV-23 as promising candidates against Gram-negative bacterial infections with a favorable therapeutic profile. This effect could be related to their great flexibility, as evidenced by circular dichroism data, confirming that the peptides could assume an α-helical conformation interacting with bacterial membranes. Full article

Methicillin-resistant Staphylococcus aureus (MRSA) is recognized as a significant pathogen playing a crucial role in causing bacterial infections of skin and soft tissues due to its high capacity for biofilm formation. Niosome-based gel systems offer significant potential for enhancing transdermal drug delivery and increasing the effectiveness of loaded drugs. The current research investigates the feasibility of niosomal gel for formulating the topical administration of teicoplanin (TEC). The thin film hydration method was used for niosome formulation was composed of nonionic surfactant, cholesterol, and mPEG 2000. TEC niosomal gel was prepared with adding hydroxypropyl methylcellulose (HPMC) and Poloxamer 407 polymers to the system. The physiochemical characteristics of prepared niosomal gel formulation, such as particle morphology, size, zeta surface charge, homogeneity, encapsulation efficiency, and in vitro drug release, were evaluated. Also, the in vitro antibacterial potential of the prepared system was analyzed. Further, we examined the in vivo antibacterial activity of the synthesized niosomal gel on infected wounds in Wister rats. We found that the TEC niosomal gel had antibacterial and anti-biofilm capabilities against MRSA isolates, and could be an effective wound material for preventing therapeutic problems related to this superbug. Full article

Background/Objectives: Atorvastatin (ATR), an antihyperlipidemic drug with a potential antibacterial effect, was investigated in this study. Like other statins, ATR has been repurposed for several uses, ranging from anti-inflammatory to antimicrobial applications, and has demonstrated successful results. However, the efficacy of ATR is limited by its low solubility, indicating an opportunity for its encapsulation in a nanotechnology-based drug delivery system. Methods: Nanostructured lipid carrier (NLC) formulations were prepared using high-pressure homogenization and ultrasonication. The formulations were characterized, including their particle size, polydispersity index, zeta potential, encapsulation efficiency, and in vitro release. Antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (E. coli), and Staphylococcus aureus (S. aureus) was evaluated using the growth curve (bacterial growth over time) and well diffusion methods (zone of inhibition and minimum inhibitory concentration (MIC) determination). The crystal violet assay was employed to assess biofilm inhibition. Results: The NLC formulations were optimized, and the size and zeta potential of the blank nanoparticles were 130 ± 8.39 nm and −35 ± 0.5 mV, respectively. In comparison, the encapsulated NLCs had a size of 142 ± 52.20 nm and a zeta potential of −31 ± 1.41 mV. The average encapsulation efficiency was 94%, and 70% of the drug was released after 24 h. The ATR-loaded NLCs showed significantly enhanced antibacterial activity by reducing the minimum inhibitory concentration by 2.5-fold for E. coli, 1.8-fold for S. aureus, and 1.4-fold for MRSA, and promoting more effective bacterial growth inhibition. Notably, biofilm inhibition was significantly improved with ATR-NLCs, achieving 80% inhibition for S. aureus, 40% for E. coli, and 30% for MRSA, compared to free ATR (p < 0.001). These findings suggest that NLC encapsulation enhances ATR’s antimicrobial efficacy and biofilm suppression. Conclusions: This study identified NLCs as successful carriers of ATR, significantly enhancing its antibacterial efficacy and biofilm inhibition capabilities. This formulation, which shows antimicrobial potential against both Gram-positive and Gram-negative bacteria, should be further studied and developed against different resistant microbial strains. Full article