Antibacterial Properties Research Articles

Synthesis and characterization of gelzan nanocomposite scaffold incorporating Ag/Fe2+ co-doped hydroxyapatite for antibacterial bone tissue regeneration

Abstract A nanocomposite scaffold was developed using gelzan, a natural extracellular polysaccharide, as the biopolymer matrix. Gelzan (GZ) was combined with Ag/Fe2⁺ co-doped hydroxyapatite (HAp) particles to enhance the scaffold’s biological properties. The aim of incorporating Ag/Fe2⁺ co-doped HAp was to utilize the combined antibacterial and bioactive properties of these components. The synthesized Ag/Fe2⁺ co-doped HAp nanoparticles, along with the gelzan-based nanocomposite scaffold produced via freeze-drying, underwent comprehensive analyses. These included Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and biological assessments for antibacterial activity and bioactivity. The results demonstrated that the Ag/Fe2⁺ co-doped HAp nanocomposite scaffold possessed favourable physicochemical properties. Furthermore, the integration of Ag and Fe2⁺ co-doped HAp into the gelzan matrix was confirmed, revealing the scaffold’s structural and compositional characteristics. Tests of apatite formation in simulated body fluid (SBF) indicated the development of layered apatite precipitates after 7 days. The scaffold also exhibited significant antibacterial activity, with inhibition zones of 7.35 ± 0.70 mm and 5.54 ± 0.60 mm against Staphylococcus aureus and Escherichia coli, respectively. These findings suggest the scaffold’s promising potential as a biomaterial for bone tissue regeneration.

Orange Peel Lactiplantibacillus plantarum: Development of A Mucoadhesive Nasal Spray with Antimicrobial and Anti-Inflammatory Activity

Background/Objectives: Due to the high frequency and severity of upper respiratory bacterial infections, probiotics could offer a new medical approach. We explored the antibacterial and anti-inflammatory properties of the new strain Lactiplantibacillus plantarum BIA and formulated a nasal spray. Methods: L. plantarum BIA was isolated from orange peel and taxonomically identified through 16S rRNA gene sequencing. Its antibacterial activity was tested against Pseudomonas aeruginosa, Streptococcus pyogenes, Bacillus subtilis, Escherichia coli, and Staphylococcus aureus, while anti-inflammatory potential was evaluated by Griess assay. BIA genome was fully sequenced and analyzed to assess its safety. BIA was formulated in a freeze-dried matrix, containing prebiotics and cryoprotectants, to be reconstituted with a polymer solution. Solutions containing two types of hydroxypropyl methylcellulose (HPMC) and hyaluronic acid were evaluated as resuspending media and compared in terms of pH, viscosity, and mucoadhesion ability. The biological activity of BIA formulated as nasal spray was verified together with the stability of the selected formulations. Results: L. plantarum BIA inhibited human pathogens’ growth and showed anti-inflammatory activity and a safe profile. In the best-performing formulation, the probiotic is lyophilized in 10% fructooligosaccharides, 0.1% ascorbic acid, and 0.5% lactose and reconstituted with HPMC high viscosity 1% w/v. This composition ensured the probiotic’s viability for up to six months in its dried form and one week after reconstitution. It also allowed interaction with the nasal mucosa, preserving its antimicrobial and anti-inflammatory activities. Conclusion: The developed nasal spray could become a promising formulation in the field of nasal infectious and inflammatory diseases.

Impact of Hyaluronic Acid and Other Re-Epithelializing Agents in Periodontal Regeneration: A Molecular Perspective

This narrative review delves into the molecular mechanisms of hyaluronic acid (HA) and re-epithelializing agents in the context of periodontal regeneration. Periodontitis, characterized by chronic inflammation and the destruction of tooth-supporting tissues, presents a significant challenge in restorative dentistry. Traditional non-surgical therapies (NSPTs) sometimes fail to fully manage subgingival biofilms and could benefit from adjunctive treatments. HA, with its antibacterial, antifungal, anti-inflammatory, angiogenic, and osteoinductive properties, offers promising therapeutic potential. This review synthesizes the current literature on the bioactive effects of HA and re-epithelializing agents, such as growth factors and biomaterials, in promoting cell migration, proliferation, and extracellular matrix (ECM) synthesis. By modulating signaling pathways like the Wnt/β-catenin, TGF-β, and CD44 interaction pathways, HA enhances wound healing processes and tissue regeneration. Additionally, the role of HA in facilitating cellular crosstalk between epithelial and connective tissues is highlighted, as it impacts the inflammatory response and ECM remodeling. This review also explores the combined use of HA with growth factors and cytokines in wound healing, revealing how these agents interact synergistically to optimize periodontal regeneration. Future perspectives emphasize the need for further clinical trials to evaluate the long-term outcomes of these therapies and their potential integration into periodontal treatment paradigms.

Investigation of water-based interior wall coatings containing epoxy resin quaternary ammonium salts with antibacterial properties

Investigation of water-based interior wall coatings containing epoxy resin quaternary ammonium salts with antibacterial properties

OZONIOTERAPIA EM CONTAMINAÇÃO DE FERIDA CIRÚRGICARELATO DE CASO EM CÃO CAUDECTOMIZADO

Integrative medicine offers a wide variety of therapies that can be associated with conventional medicine, providing patients appropriate treatment with satisfactory results. Among the therapies used in integrative medicine, we have ozone therapy, which is widely used for various purposes due to its bactericidal, fungicidal and virucidal properties and the fact that it has practically no side effects with low toxicity, being used in chronic pathological conditions, in cases of dermatitis, ulcers and redness, burns and wound healing processes. The case report shows a healing process promoted by ozone therapy and associated therapies in a dog, presenting positive results. Ozone is a colorless gas with a characteristic odor and analgesic and anti-inflammatory functions, also contributing to the immune system and body oxygenation of animals. It can be applied in distinct ways, split into local or systemic, and can be subcutaneous, intravaginal, blood therapies, bagging and cupping methods. In addition, the technique offers low cost and promotes an improvement in the animal's quality of life.

Exploring the Antibacterial Properties and Chemical Profiles of Essential Oils from Syzygium aromaticum and Nigella sativa Against MDR Bacteria

For centuries, plants have been studied for their healing properties. Recently, the rise of antibiotic resistance in bacteria has prompted scientists to explore herbal remedies. Syzygium aromaticum, from the Myrtaceae family, has been utilized as a histological clearing agent. In contrast, Nigella sativa (black cumin), a member of the Ranunculaceae family, has long been utilized in traditional medicine dating back to ancient times. The current study investigates the chemical composition and antibacterial activity of essential oils from Syzygium aromaticum (clove) and Nigella sativa (black cumin) against multidrug-resistant (MDR) bacteria. Using the agar well diffusion method, Syzygium aromaticum exhibited significant antibacterial activity, particularly against Salmonella typhi (30.66 mm inhibition zone), while Nigella sativa was effective only against Staphylococcus aureus (19 mm). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for Syzygium aromaticum ranged from 3.53 to 7.06 mg/mL, indicating stronger antibacterial properties than Nigella sativa (MIC: 12.7 mg/mL, MBC: 22.5 mg/mL). GC-MS analysis revealed that Syzygium aromaticum contained bioactive compounds like Diglycolic acid (76.59%) and Eugenol (2.06%), while Nigella sativa was dominated by Heptasiloxane (80.83%) and Thymoquinone (2.66%). These findings suggest that Syzygium aromaticum essential oil could serve as a potent natural antimicrobial agent against MDR pathogens.

Computational Investigation of Phytochemicals as Putative Inhibitors of Vibrio parahaemolyticus Protein Toxins

The lethal toxins released by pathogenic strains of V. parahaemolyticus pose a significant challenge in the aquaculture industry. One such toxin is thermostable direct haemolysin (TDH), which is encoded in the tdh gene. TDH primarily exerts its toxicity by creating pores in hemocyte membranes and other tissues. The toxR gene, on the other hand, plays a role in regulating the expression of virulence factors, including tdh, and is found in Vibrio species. Plants are recognized for containing phytochemicals that exhibit antibacterial properties with few adverse effects. This study acquired essential phytochemicals from PubChem, and target proteins from the RCSB protein data bank. The study was focused on the effects of alkaloids and flavonoid classes of phytochemicals on the target toxins measured by in silico (Gscore and MM/GBSA bind) investigation. This research employed in silico screening using Schrodinger's Glide, 2021 software, followed by a thorough analysis of how different phytochemicals interacted with specific binding sites, utilizing the Discovery Studio 3.5 version. Through this analysis, the most effective phytochemicals were identified, and myricetin (Myr) and (+)-taxifolin (TF) with ToxR, as well as chlorogenic acid (CGA) and carboxymethyl cellulose (CMC) with TDH, were analyzed. These phytochemicals displayed promising potential as inhibitors of the toxins, as evidenced by their docking scores and affinity. Among the compounds, Myr exhibited the best G-docking score at -6.004 Kcal/mol, followed by TF at -5.262 Kcal/mol against ToxR. Whereas, CGA and CMC also demonstrated notable scores at -5.245 Kcal/mol and -4.433 Kcal/mol against TDH, respectively. The in silico analysis suggested that these phytocompounds might have strong antibacterial properties against V. parahaemolyticus by effectively neutralizing these toxins. The screening results revealed several phytochemicals with promising docking scores and significant interactions with these toxins.

Effectiveness of coatings in reducing biofilm adhesion on arch wires: A systematic review

To evaluate the Effectiveness of coatings in reducing biofilm adhesion on arch wire. A literature search was performed on PubMed, Medline, Google Scholar, and Science Direct to examine studies that compared the uncoated group of arch wires to those with nano coatings and assessed the anti-adherent property. After extracting the data from each study, two risk of bias assessment tools were employed and tabulated data was obtained. 8 Studies met the requirements for inclusion. For majority of the included articles, the risk of bias assessment indicated a low to moderate risk. The antibacterial properties of various nanoparticle coatings were examined and evaluated.Regardless of patient compliance, a proper application of each type of coated arch-wire can help prevent white spot lesions and reduce bacterial aggregation around orthodontic attachments. Majority of the studies that made up this systematic review have a risk of bias grade of "fair." A meta-analysis was not feasible because of heterogeneity in the different coating techniques used to test the antibacterial property.

Carvacrol alleviates LPS-induced myocardial dysfunction by inhibiting the TLR4/MyD88/NF-κB and NLRP3 inflammasome in cardiomyocytes.

Sepsis-induced myocardial dysfunction (SIMD) may contribute to the poor prognosis of septic patients. Carvacrol (2-methyl-5-isopropyl phenol), a phenolic monoterpene compound extracted from various aromatic plants and fragrance essential oils, has multiple beneficial effects such as antibacterial, anti-inflammatory, and antioxidant properties. These attributes make it potentially useful for treating many diseases. This study aims to investigate the effects of CAR on LPS-induced myocardial dysfunction and explore the underlying mechanism. H9c2 cells were stimulated with 10µg/ml LPS for 12h, and c57BL/6 mice were intraperitoneally injected with 10mg/kg LPS to establish a septic-myocardial injury model. Our results showed that CAR could improve cardiac function, significantly reduce serum levels of inflammatory cytokines (including TNF-α, IL-1β, and IL-6), decrease oxidative stress, and inhibit cardiomyocyte apoptosis in LPS-injured mice. Additionally, CAR significantly downregulated the expression of TLR4, MyD88, and NF-κB in LPS-injured mice and H9c2 cells. It also inhibited the upregulation of inflammasome components (such as NLRP3, GSDMD, and IL-1β) in H9c2 cells triggered by LPS. Taken together, CAR exhibited potential cardioprotective effects against sepsis, which may be mainly attributed to the TLR4/MyD88/NF-κB pathway and the NLRP3 inflammasome.

A Review on Formulation and Evaluation of Herbal Face Serum

Facial wrinkles and skin aging are often caused by sun damage and UV rays, and there are currently no effective methods to slow down the aging process. Aloe Vera, glycerin, and honeybee venom are key ingredients in a concentrated face serum that helps improve skin health. Aloe Vera provides quick cosmetic benefits and also has psychological effects. The serum is easily absorbed and can penetrate deeper layers of the skin. Aloe Vera is known for treating skin issues like sunburns, minor cuts, and insect bites, and it has healing, anti-inflammatory, antibacterial, and antifungal properties. Bee venom, a toxin produced by bees, is believed to help improve blood flow and increase collagen production. The face serum was tested for its quality, including pH, consistency, and size of the droplets. Stability tests showed that the serum maintained its appearance, texture, and consistency without any changesg

A Critical Review of Postbiotics as Promising Novel Therapeutic Agents for Clostridial Infections.

Clostridial infections, known for their severity and rapid progression, present significant challenges in both clinical and veterinary fields. These bacteria, which can survive without oxygen and produce protective spores, cause many diseases, ranging from simple gastrointestinal disorders to severe and potentially fatal infections including botulism, tetanus, and gas gangrene. The rising occurrence of antibiotic-resistant strains and the repetitive character of some Clostridial illnesses, including Clostridioides difficile infections (CDI), highlight the immediate need for alternate treatment approaches. Postbiotics, which are metabolites derived from probiotics, are showing great potential as effective agents against these diseases. The current study offers a comprehensive investigation of the potential of postbiotics as therapeutic agents for treating Clostridial infections, including C. difficile, Clostridium perfringens, Clostridium botulinum, and Clostridium tetani. It also examines the processes by which postbiotics exert their effects. Preliminary investigations have shown that postbiotics have promising antibacterial and antibiofilm properties, indicating their potential as adjunct agents in methods for controlling microbial growth. Nevertheless, more study is required to thoroughly demonstrate their medicinal uses.

Green synthesis of iron and silver nanoparticles from aqueous extract of buckwheat husk waste: antibacterial, cytotoxic, and dye decolorization properties

Green synthesis of iron and silver nanoparticles from aqueous extract of buckwheat husk waste: antibacterial, cytotoxic, and dye decolorization properties

Metal-phenolic nanoparticles enhance low temperature photothermal therapy for bacterial biofilm in superficial infections.

Bacterial infections, especially induced by multidrug-resistant pathogens, have become a significant global health concern. In the infected tissues, biofilms not only serve as a source of nutrients but also act as protective barriers that impede antibiotic penetration. Herein, we developed tea polyphenols epigallocatechin gallate (EGCG) Au nanoparticles (E-Au NPs) through direct one-step self-assembly methods by EGCG chelating with Au ions to eradicate antibiotic-resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA) and prevent the formation of biofilm under near-infrared (NIR) irradiation. The outstanding antibacterial effect involved in mild photothermal therapy, reactive oxygen species production, pathogenicity-related genes regulation, and quinoprotein formation that were specific to the polyphenol-based NPs. The excellent antibacterial and anti-inflammatory therapeutic efficacy of E-Au NPs was validated and topically applied in murine MRSA-infected skin wounds and keratitis model in vivo to kill bacteria, reduce the inflammation response and promote wound healing. Furthermore, the ophthalmic and systemic biosafety profiles were thoroughly evaluated while no significant side effects were revealed achieving a balance between high-efficiency antibacterial properties and biocompatibility. This study provides an effective therapeutic agent of metal-phenolic materials for superficial tissue infection with favorable prognosis and potential in clinical translation.

The impact of varying sizes of silver nanoparticles on the induction of cellular damage in Klebsiella pneumoniae involving diverse mechanisms

Abstract Silver nanoparticles (AgNPs) are extensively studied as potent antibacterial agents targeting antibiotic-resistant pathogens. Cellular damage induced through various mechanisms that can affect multiple cell components like the outer membrane, enzymes, and proteins is closely linked to their chemical and morphological characteristics. We investigated the impact of AgNPs’ size on their antibacterial effectiveness using two differently sized nanoparticles: silver nanoparticle-Citrus limon (AgCL) with an average size of 21 nm and silver nanoparticle-Citrus sinensis (AgCS) with an average size of 13 nm, derived from C. limon and C. sinensis through environmentally friendly methods. The study evaluated their antibacterial effects by assessing morphology changes via scanning electron microscopy, metabolic alterations using Fourier transform infrared (FT-IR) spectroscopy, and oxidative stress responses through biochemical markers in Klebsiella pneumoniae cells exposed to AgNPs. The results showed that both AgCL and AgCS exhibited remarkable antibacterial activity, evidenced by inhibition zones of 14 ± 1.5 and 16 ± 1.0 mm, respectively. Morphological changes in K. pneumoniae cells treated with AgNPs were size dependent, with notable alterations noted. FT-IR spectroscopy revealed size and concentration-dependent biochemical changes, particularly in shifts in functional groups involved in the fluidity of cell wall lipid, and protein structure. Exposure to AgNPs led to increased oxidative stress markers like lipid peroxides and reduced levels of enzymatic and non-enzymatic antioxidants, more prominently observed with smaller AgCS nanoparticles (13 nm). AgNPs induce oxidative stress and morphological changes in K. pneumoniae strains, with smaller nanoparticles demonstrating greater efficacy. These findings underscore the importance of nanoparticle size in optimizing the antibacterial properties against pathogens.

New emerging materials with potential antibacterial activities.

The increasing prevalence of multidrug-resistant pathogens is a critical public health issue, necessitating the development of alternative antibacterial agents. Examples of these pathogens are methicillin-resistant Staphylococcus aureus (MRSA) and the emergence of "pan-resistant" Gram-negative strains, such as Pseudomonas aeruginosa and Acinetobacter baumannii, which occurred more recently. This review examines various emerging materials with significant antibacterial activities. Among these are nanomaterials such as quantum dots, carbon quantum dots, metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and layered double hydroxides, all of which demonstrate excellent antibacterial properties. Interestingly, including antibacterial agents within the structure of these materials can help avoid bacterial resistance and improve the long-term efficacy of the materials. Additionally, the antibacterial potential of liquid solvents, including ionic liquids and both deep eutectic solvents and natural deep eutectic solvents, is explored. The review discusses the synthesis methods, advantages, and antibacterial efficacy of these new materials. By providing a comprehensive overview of these innovative materials, this review aims to contribute to the ongoing search for effective solutions to combat antibiotic resistance. Key studies demonstrating antibacterial effects against pathogens like Escherichia coli, Staphylococcus aureus, and multidrug-resistant strains are summarized. MOFs have exhibited antibacterial properties through controlled ion release and surface interactions. COFs have enhanced the efficacy of encapsulated antibiotics and displayed intrinsic antibacterial activity. Other nanomaterials, such as quantum dots, have generated reactive oxygen species, leading to microbial inactivation. This review aims to provide insights into these new classes of antibacterial materials and highlight them for addressing the global crisis of antibiotic resistance. KEY POINTS: • Nanomaterials show strong antibacterial effects against drug-resistant bacteria • Emerging solvents like ionic liquids offer novel solutions for bacterial resistance • MOFs and COFs enhance antibiotic efficacy, showing promise in combating resistance.

Enzymatization of Nila Fish (Oreochromis Niloticus) Protein Hydolysate by Combination of Bromelin and Pepsin Enzymes

Nile Tilapia (Oreochromis niloticus) is a freshwater fish with better nutritional content compared to other freshwater fish, making it suitable for use as a source for protein hydrolysate production. Protein hydrolysate is the result of the breakdown of protein into short-chain compounds through hydrolysis. This research aims to hydrolyze the minced Nile tilapia meat using a combination of bromelain and pepsin enzymes at a concentration of 5% and pH 7 conditions for 5-6 hours. The hydrolysis results using the combination of bromelain and pepsin enzymes (B100: P0) have a yield value of 12.68%, ash content of 2.94%, protein of 57.25%, water 2.65%, and fat 10.25% with a degree of hydrolysis of 61.46%. The hydrolysate has antibacterial properties against Staphylococcus aureus and Escherichia coli bacteria with inhibition zones of approximately 8.3 mm and 8.5 mm, respectively, at a concentration of 1 (mg/µL), contains 15 types of amino acids with the highest composition being lysine 5.12% and the highest non-essential amino acid being aspartic acid 5.75%.

Self-Healing, Electrically Conductive, Antibacterial, and Adhesive Eutectogel Containing Polymerizable Deep Eutectic Solvent for Human Motion Sensing and Wound Healing.

Flexible electronic devices such as wearable sensors are essential to advance human-machine interactions. Conductive eutectogels are promising for wearable sensors, despite their challenges in self-healing and adhesion properties. This study introduces a multifunctional eutectogel based on a novel polymerizable deep eutectic solvent (PDES) prepared by the incorporation of diallyldimethylammonium chloride (DADMAC) and glycerol in the presence of polycyclodextrin (PCD)/dopamine-grafted gelatin (Gel-DOP)/oxidized sodium alginate (OSA). The synthesized eutectogel has reversible Schiff-base bonds, hydrogen bonds, and host-guest interactions, which enable rapid self-healing upon network disruption. GPDO-15 eutectogel has significant tissue adhesion, high stretchability (419%), good ionic conductivity (0.79 mS·cm-1), and favorable antibacterial and self-healing properties. These eutectogels achieve 90% antibacterial effect, show excellent biocompatibility, and can be used as sensors to monitor human activities with strong stability and durability. The in vivo studies indicate that the eutectogels can improve the wound healing process which makes them an effective option for biological dressings.

Phytogenic Synthesis of Cuprous and Cupric Oxide Nanoparticles Using Black jack Leaf Extract: Antibacterial Effects and Their Computational Docking Insights

Background: Green synthesized nanoparticles (NPs) have gained increasing popularity in recent times due to their broad spectrum of antimicrobial properties. This study aimed to develop a phytofabrication approach for producing cuprous (Cu2O) and cupric oxide (CuO) NPs using a simple, non-hazardous process and to examine their antimicrobial properties. Methods: The synthesis employed Bidens pilosa plant extract as a natural reducing and stabilizing agent, alongside copper chloride dihydrate as the precursor. The biosynthesized NPs were characterized through various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Results: XRD analysis confirmed that the synthesized CuO and Cu2O NPs exhibited a high degree of crystallinity, with crystal structures corresponding to monoclinic and face-centered cubic systems. SEM images revealed that the NPs displayed distinct spherical and sponge-like morphologies. EDS analysis further validated the purity of the synthesized CuO NPs. The antimicrobial activity of the CuO and Cu2O NPs was tested against various pathogenic bacterial strains, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus, with the minimum inhibitory concentration (MIC) used to gauge their effectiveness. Conclusions: The results showed that the phytosynthesized NPs had promising antibacterial properties, particularly the Cu2O NPs, which, with a larger crystal size of 68.19 nm, demonstrated significant inhibitory effects across all tested bacterial species. These findings suggest the potential of CuO and Cu2O NPs as effective antimicrobial agents produced via green synthesis.

Effectiveness of cold atmospheric plasma in decontaminating enterococcus faecalis colonized collagen and PTFE membranes used in guided bone regeneration: a comparative in vitro investigation.

Wound healing disorders caused by bacterial infections in dental surgery, especially where membranes are used, are a common issue in oral surgery. Cold atmospheric plasma (CAP) offers a non-invasive solution for surface decontamination, including dental implants. The aim of this study was to evaluate the antibacterial effectiveness of CAP on various clinically applied membranes made of collagen and polytetrafluoroethylene (PTFE). To assess the antibacterial properties of CAP, enterococcus faecalis were seeded on different membranes: Memlock (collagen), Memlock Pliable (collagen), Agronaut (collagen), and PermaPro (PTFE); n = 4. After in vitro cultivation for 6days, CAP using a kINPen® MED with an output of 5 W was applied 5min and 10min. Bacterial colony-forming units (CFU) were quantified to detect decontamination effectiveness. In addition, live and dead staining as well as scanning electron microscopy (SEM) of membranes was performed for validation and surface texture analysis. Bacterial colonization was highest on collagen-based membranes (CFU Memlock: 14.38 ± 8.91). The results showed that CAP significantly reduced bacterial colonization on all membrane types after 10min application of CAP; Memlock (CFU after 10min 0.22 ± 0.16^106; p = 0.0256), Argonaut (CFU after 10min 0.02 ± 0.01^106; p = 0.0129) and PermaPro (complete bacterial decontamination; p = 0.0058). This was paralleled by fluorescence and scanning electron microscopy. CAP was most effective on smooth membrane surfaces as SEM revealed. CAP thus offers a non-invasive, cost-effective method to reduce bacterial infections in guided bone regeneration using membranes.

Synthesis and evaluation of vanillin Schiff bases as potential antimicrobial agents against ESBL-producing bacteria: towards novel interventions in antimicrobial stewardship.

The escalating challenge of antimicrobial resistance necessitates the development of novel antibacterial agents. In this study, a series of five vanillin Schiff bases (SB-1 to SB-5) were synthesized from vanillin and various aromatic amines. The chemical structures of these compounds were characterized using Thin Layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FT-IR), proton nuclear magnetic resonance ( -NMR), carbon-13 NMR ( -NMR), and mass spectrometry techniques. Antibacterial efficacy was evaluated against strains of bacteria producing extended-spectrum beta-lactamases (ESBL), including Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae using the disc diffusion method. Cytotoxic effects were assessed through haemocompatibility and brine shrimp lethality assays. The Schiff bases demonstrated notable antibacterial activities, with SB-1, SB-2, SB-4, and SB-5 exhibiting zones of inhibition up to 16.0, 16.5, 16.6, and 15.5 mm against ESBL E. coli, respectively. SB-3 showed a maximum inhibition zone of 15.0 mm against ESBL K. pneumoniae. In cytotoxicity assays, the compounds exhibited IC values against red blood cells (RBCs) greater than 200 μg/mL and ranging from 45.7 to 50.5 μg/mL for the brine shrimp assay. While demonstrating potent antibacterial properties, the toxicity towards human RBCs suggests that further toxicity evaluations and structural modifications are essential for developing safer therapeutic agents based on vanillin Schiff bases.