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Purpose: Since decades, numerous antibiotics have been used to treat different bacterial illnesses; among these, tetracycline is one of the commonly used antibiotics, which has led to development of bacterial resistance. To tackle this critical issue, we have developed a novel, biocompatible nanodrug that improves the antibacterial activity of tetracycline by conjugating it with copper oxide nanoparticles, thereby addressing the problem of multidrug resistance in bacteria. Methods: In this study, using unipot approach, tetracycline conjugated copper oxide nanoparticles were synthesized where tetracycline act as reducing as well as stabilizing agent. These nanoparticles were characterized by different analytical and microscopic technique. For statistical analysis, FFD and CCD model were employed to assess the effect of various parameters (concentration, pH, temperature and time). Results: The synthesis of nanoparticles was confirmed through different techniques. Synthesized nanoparticles exhibited the highest antibacterial activity against various microbes including multi‐drug resistant microbes compared to its individual constituents. DPPH and ABTS assays revealed high antioxidant activity of nanoparticles whereas, biocompatibility was assessed via MTT assay. The drug release profile confirms the sustained release of tetracycline molecules. Conclusions: We have successfully developed tetracycline conjugated copper oxide nanoparticles exhibiting potent antibacterial, antioxidant and biocompatible activity. [ABSTRACT FROM AUTHOR]

Petiveria alliacea L. (Petiveriaceae), a medicinal plant found in tropical regions of South and Central America, the Caribbean, and Africa, is mainly used to treat inflammatory process and respiratory problems. In this study, we have evaluated the antibacterial activity of P. alliacea crude extract and fractions, investigated the chemical composition, and developed and validated a simple method to quantify flavanones. To verify the antibacterial activity, we determined the minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli. Phytochemical investigations were carried out by chromatographic and spectroscopic analysis. To quantify astilbin and engeletin, we developed a method based on HPLC coupled to a diode array detector (DAD) and validated it. The P. alliacea crude extracts and fractions exhibited MIC ranged from 10 to 25 mg/mL. Chemical investigation of P. alliacea revealed the presence of trans-N-methyl-4-methoxyproline (1), ethyl-β-galactoside (2), ethyl-α-galactoside (3), and ethyl-β-fructofuranoside (4). The developed HPLC-DAD method proved suitable for determining flavonoids in P. alliacea: it presented good linearity, specificity, and satisfactory accuracy and precision. The developed HPLC-DAD method can quantify the P. alliacea chemical markers. The isolated compounds (2–4) have been described in P. alliacea for the first time. [ABSTRACT FROM AUTHOR]

Development of new antibacterial materials for solving biomedical problems is an extremely important and very urgent task. This review aims to summarize recent articles (from the last five and mostly the last three years) on the nanoparticle/polymer composites for biomedical applications. Articles on polymeric nanoparticles (NPs) and hydrogel-based systems were not reviewed, since we focused our attention mostly on the composites of polymeric matrix with at least one inorganic filler in the form of NPs. The fields of application of newly developed antibacterial NPs/polymer composites are described, along with their composition and synthetic approaches that allow researchers to succeed in preparing effective composite materials for medical and healthcare purposes. [ABSTRACT FROM AUTHOR]

Antibacterial agents play a crucial role in healthcare and public health by combating bacterial infections. However, the emergence of antibiotic resistance necessitates a deeper understanding of 6 their mechanisms of action. This review explores the use of spectroscopic techniques, including UV-Vis, FTIR, NMR, Raman spectroscopy, mass spectrometry, and fluorescence spectroscopy, to elucidate the mechanisms of action (MOA) of antibacterial agents in the period from 2003 to 2024. The review discusses how these techniques can elucidate the MOA of classical antibiotics, antiseptics and antimicrobial peptides. Since these spectroscopic techniques provide valuable insights into the molecular interactions between antibacterial agents and bacteria, offering a comprehensive understanding of their mechanisms at a molecular level. By studying electronic transitions, chemical bond vibrations, metabolomics, and protein interactions, researchers can gain in-depth knowledge of antibacterial MOAs. This knowledge can inform the development of improved treatments and strategies to combat bacterial resistance, leading to better patient outcomes and global public health. [ABSTRACT FROM AUTHOR]

In composite materials consisting of silver particles and a polypropylene matrix, the silver must migrate to the surface of the materials in order to exert on antibacterial effect. Substrates with various crystal structures may have different interactions with the silver particles, which can significantly impact the antibacterial performance. The research described in this paper investigates the influence of silver particles on the crystallization behavior of materials with varying crystallinity capabilities by selecting various polypropylene-based plastics and elastomers (Homopolymer polypropylene (PPH-T03), random poly(propylene/ethylene) copolymers (PPR-YPR503 and PPR-P340R), polyolefin elastomers (VERSIFY3000 (POE-1) and VERSIFY3401 (POE-2)), and ethylene propylene diene monomer for polymers (EPDM4725 and EPDM4770)). The research results indicated that the silver only entered the amorphous regions of the PP rather than entering the crystal regions, where they can more easily migrate to the material surface, resulting in a higher antibacterial effect. Therefore, the antibacterial degree of PP-Ag was as high as 99.9%. Silver can enter the micro-crystals of both the random copolymer polypropylene, (PPR-YPR503, PPR-1) and the random copolymer polypropylene, (PPR-P340R, PPR-2,) with a stronger effect on PPR-2. More silver entered the micro-crystals of PPR-2, and it was difficult for the silver ions to migrate out of the crystalline regions to exhibit antibacterial properties. The antibacterial degree of PPR-1-Ag was higher than that of PPR-2-Ag (77.8% vs. 66.7%). Similarly, silver had a greater impact on the lamellar structure of the polyolefin elastomer (VERSIFY3401, POE-2) compared to the polyolefin elastomer (VERSIFY3000, POE-1). In comparison with POE-2-Ag, POE-1-Ag exhibited a higher antibacterial degree (79.6% vs. 57.4%). Research on the two types of ethylene propylene diene monomer (EPDM) composite materials indicated that EPDM-1 exhibited a lower Mooney viscosity and poorer flowability. The EPDM-1 tended to encapsulate the silver within its molecular chains, thereby impeding the migration of silver to the surface. The optical performance analysis indicated that silver antibacterial agents had little impact on the optical properties of PP-Ag, PPR-1, PPR-2, POE-1, POE-2 and the EPDMs. We suggest that this research provides theoretical guidance for selecting highly antibacterial polypropylene materials. [ABSTRACT FROM AUTHOR]

Background: Microecological equilibrium is essential for human health. Previous research has demonstrated that Streptococcus strain A, the main bacterial group in the respiratory tract, can suppress harmful microbes and protect the body. In this study, Streptococcus strain D19T was isolated from the oral and pharyngeal cavities of healthy children. Its antibacterial mechanism against Acinetobacter baumannii was examined, as well as its potential to prevent inflammatory damage to cells. We evaluated the effect of the fermentation conditions of D19T on inhibition of Acinetobacter baumannii growth; Isolation and purification of antibacterial active components of strain D19T and molecular mechanism of inhibition of Acinetobacter baumannii; Molecular mechanism of D19T antibacterial protein reversing cellular inflammatory injury induced by Acinetobacter baumannii. Results: The supernatant of fermentation broth of Streptococcus D19T was the active component against Acinetobacter baumannii, but the bacteria had no antibacterial activity. The supernatant of D19T fermentation broth was precipitated by (NH4)2SO4 solution, and the protein was the active antibacterial component. After gel filtration chromatography and anion gel filtration chromatography, the molecular weight of antibacterial protein was 53kD. D19T antibacterial protein can improve cell membrane permeability, limit extracellular soluble protein release, inhibit Acinetobacter baumannii biofilm formation, and prevent Acinetobacter baumannii adhesion. Acinetobacter baumannii induces inflammatory damage to respiratory cells via ferroptosis, and the D19T antibacterial protein can counteract this damage, protecting the respiratory tract. Conclusion: Streptococcus strain D19T, as a potential probiotic, inhibits the growth of Acinetobacter baumannii and the inflammatory damage of respiratory cells, playing a protective role in human respiratory health. [ABSTRACT FROM AUTHOR]

The development of new antibacterial drugs is essential for staying ahead of evolving antibiotic resistant bacterial (ARB) threats, ensuring effective treatment options for bacterial infections, and protecting public health. Herein, we successfully designed and synthesized two novel gold(III)‐ NHC complexes, [Au(1)(bpy)Cl][PF6]2 (2) and [Au(1)(phen)Cl][PF6]2 (3) based on the proligand pyridyl[1,2‐a]{2‐pyridylimidazol}‐3‐ylidene hexafluorophosphate (1⋅HPF6) [bpy=2,2′‐bipyridine; phen=1,10‐phenanthroline]. The synthesized complexes were characterized spectroscopically; their geometries and structural arrangements were confirmed by single crystal XRD analysis. Complexes 2 and 3 showed photoluminescence properties at room temperature and the time‐resolved fluorescence decay confirmed the fluorescence lifetimes of 0.54 and 0.62 ns respectively; which were used to demonstrate their direct interaction with bacterial cells. Among the two complexes, complex 3 was found to be more potent against the bacterial strains (Staphylococcus aureus, Gram‐positive and Pseudomonas aeruginosa, Gram‐negative bacteria) with the MIC values of 8.91 μM and 17.82 μM respectively. Studies revealed the binding of the complexes with the fundamental phospholipids present in the cell membrane of bacteria, which was found to be the leading cause of bacterial cell death. Cytotoxicity was evaluated using an MTT assay on 293 T cell lines; emphasizing the potential therapeutic uses of the Au(III)‐NHC complexes to control bacterial infections. [ABSTRACT FROM AUTHOR]

In search of better antibacterial and antibiofilm agents, this report presents a series of novel 1,2,3‐triazole‐imidazole‐benzenesulfonamide derivatives that were synthesized and evaluated for their antibacterial and antibiofilm activity in vitro. Antibacterial activity against three Gram‐positive bacterial strains, B. subtilis, S. aureus, and S. epidermidis, was evaluated. Among all the tested compounds, 4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)‐N‐((1‐(4‐(trifluoromethyl)phenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)benzenesulfonamide and N‐((1‐(3,5‐difluorophenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)benzenesulfonamide exhibited potent antibacterial activity against S. aureus and B. subtilis bacterial strains. Biofilm profiles for the potent compounds and it was observed from the results that the above two active compounds displayed promising biofilm inhibition against B. subtilis and S. aureus, with MIC values ranging between 2.19 ± 0.37 and 3.38 ± 0.35 µg/mL. Furthermore, potent compounds screened for their in silico molecular docking studies against penicillin‐binding protein and compound N‐((1‐(3,5‐dichlorophenyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐4‐methyl‐N‐(1‐methyl‐1H‐imidazol‐2‐yl)benzenesulfonamide show highest binding energy as compared to the standard and remaining compounds. [ABSTRACT FROM AUTHOR]

The present work illustrates the synthesis of some new mono‐azo dyes, which include different amines such as 2‐amino thiazole, 2‐amino‐5‐methyl‐1,3,4‐thiadiazole, and 2‐amino‐5‐methyl thiazole with 3‐diethylamino phenol as a common coupling component. The prepared azo moieties were structurally confirmed by spectroscopic techniques like NMR (1H and 13C), FT‐IR, UV –absorption, and emission properties, and HR‐MS spectrometry. Significant variations in the absorption and emission wavelengths of the azo dyes were shown by the solvatochromic behavior, which also provided an important insight into the formation of azo and hydrazone tautomeric forms. The density functional theory of the dyes was carried out to know the HOMO‐LUMO energy gaps, molecular electrostatic potential, and reduced density gradient. Further, they were screened for their in vitro antibacterial and antioxidant activities, and the results showed that the compounds exhibited excellent potentialities against various strains. [ABSTRACT FROM AUTHOR]

Transition element‐based materials hold advantageous morphological and physicochemical attributes due to their remarkably varying valence states and highly stable metal ions. Amidst them, manganese dioxide (MnO2) has gained massive interest from researchers due to its ease of fabricating diverse nanostructures with unique morphological, physicochemical, and optoelectronic features. In addition, MnO2 has displayed exciting potential as biomedicine owing to its good biocompatibility, large surface area, and ultrathin thickness. This allows its participation in intracellular biochemical reactions, causing alteration of the internal microenvironment. To domain these exceptional features and enhance biocompatibility, several MnO2‐based nanocomposites have been devised by researchers. In this review article, we attempt to provide a comprehensive assessment of various MnO2‐based nanoparticle synthesis and its corresponding antibacterial activity explored over the past decade. [ABSTRACT FROM AUTHOR]

Hydrogel dressings play an important role in the treatment of bacterial infection. In this study, carboxymethyl chitosan (CM‐CS) was cross‐linked with aldehyde polyglycol (DF‐PEG), and then polydopamine (pDA) and 5,10,15, 20‐tetrakis (4‐aminophenyl) porphyrin (TAPP) were grafted to prepare a CM‐CS/DF‐PEG/pDA/TAPP hydrogel (CDPT). The results showed that the CDPT hydrogel had good adhesion, injectability, self‐healing, degradability, and biocompatibility. Under near‐infrared irradiation, the CDPT hydrogel has excellent photothermal and photodynamic effects and can effectively inhibit activity of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and antibiotic‐resistant, methicillin‐resistant Staphylococcus aureus (MRSA). In summary, CDPT hydrogel has potential applications as antibacterial material. [ABSTRACT FROM AUTHOR]

According to the Global Burden of Disease Study and the World Health Organization, dental caries is one of the most prevalent oral diseases globally. It is well known that dental caries are associated with cariogenic bacteria and their biofilm. Many preventive strategies and therapeutic compounds have been proposed for decades. Among them, various plant-based phytochemical compounds have been investigated against cariogenic bacteria. In this review, we plan to show the effectiveness of Zingiber officinale to reduce dental caries. Z. officinale in ginger is a bioactive spice compound that shows antimicrobial activity. Therefore, it is reasonable to consider the antimicrobials and biofilm inhibition properties of bioactive Z. officinale to rationalize its potential in reducing dental caries. While the literature highlights the general antimicrobial properties of Z. officinale, this review focuses on Z. officinale's capability against cariogenic microbes and their biofilms. Reported results of minimum inhibition concentration (MIC), minimum bactericidal concentration (MBC), and biofilm inhibition (glucans and adhesion) were systematically reviewed. Common search engines like PubMed, Science Direct, and the Web of Science database are used to retrieve data using the keywords "Zingiber officinale" and "dental caries". Out of 122 resulting reports, 11 of them were included in this review. It can be concluded that Z. officinale effect against cariogenic bacteria varies depending on microbial and analytical factors. However, translational advanced studies have not yet been conducted to verify its clinical application. [ABSTRACT FROM AUTHOR]

Mycetoma is currently considered as a neglected tropical disease. The incidence of mycetoma is unknown but most of the worldwide cases are present in the "mycetoma belt" including countries like Mexico, India, Senegal, and others. The treatment of mycetoma depends on the etiological agent responsible for the case. Treatment success reaches 60 to 90%; however, common treatment has been reported to be ineffective in some cases, due in part to resistance to the prescribed antibiotics. Therefore, it is necessary to develop new therapeutic options. In the past two decades, quinoxaline derivatives have shown relevance as antibacterial agents. Therefore, in this work, esters of quinoxaline 1,4-di-N-oxide derivatives were evaluated in vitro against the reference strain CECT-3052 from N. brasiliensis, six clinical isolates, and macrophages J774A.1 to determine their cytotoxicity and security index. Additionally, nine reference drugs were evaluated as controls. The results show that nine esters of quinoxaline 1,4-di-N-oxide derivatives had a minimum inhibitory concentration (MIC) < 1 µg/mL against the reference strain and four of them (N-05, N-09, N-11, and N-13) had an MIC < 1 µg/mL against the clinical isolates. Therefore, the scaffold quinoxaline 1,4-di-N-oxide could be used to develop new and more potent antinocardial agents. [ABSTRACT FROM AUTHOR]

The rise of vancomycin-resistant enterococci (VRE) due to antibiotic overuse poses a significant threat to long-term care patients and those with impaired immune systems. Therefore, it is imperative to seek alternatives to overcome multidrug resistance. This study aimed to evaluate totarol, a natural compound derived from Podocarpus totara, for its antibacterial activity against vancomycin-resistant Enterococcus faecalis (VREF). Totarol exhibited potent antibacterial activity at a very low concentration of 0.25 µg/mL and demonstrated antibiofilm effects through biofilm inhibitory concentration and biofilm eradication concentration assays. Confocal laser scanning microscopy confirmed that totarol inhibited not only biofilm mass but also bacterial cell viability. The combinatorial use of sublethal concentrations of totarol and vancomycin showed antibacterial activity, as observed in the time-kill assay. Quantitative polymerase chain reaction assays revealed a concentration-dependent downregulation of key virulence genes (vanA, ace, asa, efaA, and esp) in VREF when exposed to totarol. In summary, totarol emerges as a promising adjuvant with vancomycin for inhibiting VREF, addressing vancomycin resistance and biofilm formation—critical challenges associated with VRE infection. Since this was an in vitro study, the role of totarol in the clinical implications of VREF treatment remains to be demonstrated. [ABSTRACT FROM AUTHOR]

Acne is a common skin condition that affects people of all ages and can lead to significant physical and psychological distress. The first line of action against acne is topical products, though the most effective are topical antibiotics. In such a scenario, the development of effective and safe herbal formulations for the treatment of acne is of great importance. Rubia cordifolia, Aloe barbadensis, and Allium cepa extracts are rich sources of bioactive metabolites and are safe compared with antibiotics, in addition to being cost effective, sustainable, and eco-friendly. Also, their combination has not been studied for treating acne, and their potential benefits need to be investigated. The present study aimed to develop an effective polyherbal gel formulation of R. cordifolia, A. barbadensis, and A. cepa combined extract for treating acne and validate its effect with reference to conventional antibiotics. Plant materials were extracted in water by the reflux method, and phytochemical analysis was done for flavonoid, anthraquinone, and phenolic contents. The combined extract (R. cordifolia, A. barbadensis, and A. cepa extracts) was formulated in gel. The selected polyherbal gel was evaluated for in vitro antibacterial activity using agar well diffusion against Cutibacterium acnes (P. acnes) culture. Phytochemical analysis of the composite extract revealed the rich presence of flavonoids, phenolics, and anthraquinones. The polyherbal gels showed good physicochemical properties; however, FCEG-4 was selected for further studies. It was found to be effective against C. acnes (MTCC 1951) in agar well diffusion, as it showed a similar zone of inhibition as that of standard. Also, during in vivo studies, FCEG-4 showed comparable efficacy with clindamycin gel. It was concluded from the study that composite extracts incorporated in an aqueous-based gel system were effective in topical therapy of mild acne vulgaris, showing similar efficacy to that of clindamycin cream. [ABSTRACT FROM AUTHOR]

Traditional herbal medicines have been used for millennia and they are currently experiencing a surge in popularity among both medical experts and those who are looking for therapy. One can find a wide variety of phytopharmaceuticals that are derived from plants in them. The most recent clinical trial demonstrated that the methanolic extract of Samadera indica was risk-free and would not cause any harm to any individual. Due to the fact that they have favorable physical qualities, the components that were created were suitable for use on the skin. When it came to eliminating bacteria and fungi in the laboratory, the gel that was produced from the methanolic extract of Samadera indica proved to be far more successful than the product that is commonly accessible. Further evidence that the substance was both chemically and physically stable was provided by the fact that the formulae that were developed demonstrated short-term stability. [ABSTRACT FROM AUTHOR]

The aim of this study was identification and characterization of highly efficient Exopolysaccharide (EPS) producing bacteria in marine sediment soil. To identify specific exopolysaccharide producing bacteria, observations were collected regarding their morphological, physiological, and biochemical characteristics. The findings indicated that Halomonas sp. is the genus to which this bacterium belongs. The following elements were present (carbon, hydrogen, nitrogen and sulfur) in EPS. Further, to confirm the biological potential, the antibacterial Shigella flexneri (MTCC 1457), Proteus mirabilis (MTCC 1429), Escherichia coli (MTCC 43) and Streptococcus pneumoniae (MTCC 655) and MIC properties of exopolysaccharide. MTT assay was used to assess the effect of EPS on growth of Hep G2 (Hepatocellular carcinoma) cell line. These cells were cultured under different concentrations rate of EPS. The inhibitory concentrations (IC50 value) of the tested EPS was found to be 21.188215 µl/ml. Annexin V/PI staining confirmed the apoptosis induced by EPS in Hep G2 cells. [ABSTRACT FROM AUTHOR]

Many polymeric film formulas containing antibiotics failed in preventing microbial infections due to microbial resistance. One of the main reasons for microbial resistance is the formation of biofilm layers which prevent the drug from reaching the active site. This study aims to evaluate the effect of dexamethasone addition to polymeric film formula containing gentamicin. The polymeric formula containing both dexamethasone and gentamicin were characterized in terms of film's diameters, content uniformity, moisture content, matrix‐drugs association, and drug release. Antibiofilm and antimicrobial activity were used to evaluate polymeric formula containing drug. The addition of dexamethasone to the polymeric formula revealed that most of dexamethasone released and diffused in the first 300 min, while gentamicin release and diffusion had a slower rate like the release of gentamicin from formulations without dexamethasone. The addition of dexamethasone resulted in improved antibiofilm and antibacterial activity with the lowest antibiofilm activity >96% and antibacterial activity >87%. Therefore, dexamethasone addition to polymeric formula containing gentamicin improved the biological activity without any effects on the film characteristics. Highlights: Dexamethasone addition to polymeric formula containing gentamicin significantly improved the biological activity.Most of dexamethasone released and diffused in the first 300 min.The addition of dexamethasone resulted in the lowest antibiofilm activity of gentamicin of >96% and antibacterial activity >87%. [ABSTRACT FROM AUTHOR]

In this study, we aimed to fabricate a novel, completely natural antibacterial disinfectant material for environmental applications, such as treating drinking water. We created two different berberine−alginate (BerAlg) beads using the ionotropic gelation method, employing calcium and aluminium ions as cross-linkers. The materials were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), swelling, and release kinetic studies. Antibacterial activity was assessed through time-kill analysis. Among the four release kinetics models tested, the BerAlg bead formulation showed the best fit with the Korsmeyer−Peppas model, having the highest R2 value (0.9757). The longest release of berberine (Ber) was observed over a 4-h period. The time-kill assay results revealed that BerAlg beads were effective in killing for up to 7 h. In conclusion, these results demonstrate the promising potential of BerAlg beads as an antibacterial delivery system for disinfecting various liquid environments, such as drinking water. [ABSTRACT FROM AUTHOR]

Smart antibacterial coatings with surface‐independent methods, on‐demand antibiotic release, and real‐time drug loading monitoring capabilities have attracted increasing interest in the fields of medical devices, antibiotics delivery platforms, and implantable devices. Addressing the complexity inherent in existing methods, this work innovates by simplifying the synthesis process and integrating aminoglycosides with metallosupramolecules to develop versatile and effective coatings. These coatings not only exhibit exceptional biological activity and efficient antibacterial properties both in vitro and in vivo, but also enable high drug loading and controlled release. Significantly, their application across various devices has demonstrated profound therapeutic effects in treating implant infections and promoting bacterial wound healing. A key advancement of these coatings is the integration of color‐changing indicators for real‐time monitoring of drug levels, enhancing the precision of wound care, and facilitating timely clinical interventions. This research marks a significant stride in the development of more accessible, bioactive, and smart antibacterial materials, opening new avenues in the field of smart medical coatings. [ABSTRACT FROM AUTHOR]

One of the most effective ways to reduce environmental pollution on the earth's surface is the catalytic decomposition method. In this paper, the co-precipitation method was successfully used to synthesize pure and Sm (3, 5, and 7 wt%) doped WO 3 nanoparticles by various weight percentage. The structural and optical properties of prepared NPs were characterized using XRD, SEM, EDS, HR-TEM, XPS, FTIR and UV–Vis. From XRD analysis confirmed the monoclinic phase of WO 3 as well as the substitutional incorporation of Sm in WO 3 lattice. The surface morphology of the obtained samples was studied by SEM and HR-TEM, which shows nanoplate morphology. EDS and XPS analysis element confirmation for W, O and Sm. The systematic decrease of bandgap (E g) from 2.86 to 2.82 eV with increasing Sm doping concentration from 0 to 7 wt% was strong evidenced from UV–Vis analysis. Furthermore, the extensive surface area of the active CV curves and EIS indicating the good to improve photocatalytic performance and photo-generated carriers' separation efficiency. The photodegradation of Methyl Blue (MB) aqueous solution in 120 min under the visible light irradiation is used to assess the photocatalytic activity of the prepared samples. Among the four samples, 7 wt% doped one shows higher degradation efficiency of 94.2 %. Finally, the antibacterial properties of Sm:WO 3 (0, 3, 5 and 7 wt%) NPs against Staphylococcus aureus (MTCC 8708) were investigated with the disc diffusion method and zone of inhibition in mm were recorded. Based on the above analysis, the superior antibacterial activity against Staphylococcus aureus (18 mm) is rather obtained with Sm:WO 3 (7 wt%) sample. [ABSTRACT FROM AUTHOR]

The antibacterial properties of modified silk fibroin microfibers (SF MFs) have been widely studied. Among various modifications, integration of silver nanoparticles (Ag NPs) and SF MFs has garnered significant attention due to the broad‐spectrum antibacterial activities and long‐term antibacterial effect of Ag nanomaterials. However, the traditional introduction of reducing agents or other additives during the synthesis of Ag‐SF composite MFs potentially affects their structure and antibacterial properties. Facile, green and effective methods for the preparation of Ag‐SF MFs with enhanced antibacterial properties are therefore highly desired. In this study, Ag NPs were uniformly in‐situ deposited onto the optimized SF MFs by adjusting the pH and duration conditions under the guidance of green chemistry. The loaded Ag NPs have a good dispersibility and an average size of ~10 nm. The stability of SF MFs after the deposition of Ag NPs and the crystalline features of the loaded Ag NPs have been carefully investigated. Moreover, antibacterial experiments confirmed that Ag‐SF MFs exhibited superior antibacterial activities. After co‐incubating Ag‐SF MFs with L929 cells, the cell viability reached 90 %, demonstrating the great biocompatibility of the modified fibers. This green in‐situ synthetic method will promote the further medical use of Ag‐SF MFs in antibacterial fields. [ABSTRACT FROM AUTHOR]

Antibacterial resistance requires an advanced strategy to increase the efficacy of current therapeutics in addition to the synthesis of new generations of antibiotics. In this study, copper oxide nanoparticles (CuO-NPs) were green synthesized using Moringa oleifera root extract. CuO-NPs fabricated into a form of aspartic acid-ciprofloxacin-polyethylene glycol coated copper oxide-nanotherapeutics (CIP-PEG-CuO) to improve the antibacterial activity of NPs and the efficacy of the drug with controlled cytotoxicity. These NPs were charachterized by Fourier transform infrared spectroscopy (FTIR), x-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Antibacterial screening and bacterial chemotaxis investigations demonstrated that CIP-PEG-CuO NPs show enhanced antibacterial potential against Gram-positive and Gram-negative clinically isolated pathogenic bacterial strains as compared to CuO-NPs. In ex-vivo cytotoxicity CIP-PEG-CuO-nano-formulates revealed 88% viability of Baby Hamster Kidney 21 cell lines and 90% RBCs remained intact with nano-formulations during hemolysis assay. An in-vivo studies on animal models show that Staphylococcus aureus were eradicated by this newly developed formulate from the infected skin and showed wound-healing properties. By using specially designed nanoparticles that are engineered to precisely transport antimicrobial agents, these efficient nano-drug delivery systems can target localized infections, ensure targeted delivery, enhance efficacy through increased drug penetration through physical barriers, and reduce systemic side effects for more effective treatment. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the chemical composition, antioxidant, cytotoxic, and antibacterial activities of the essential oil extracted from the aerial parts of Macrothelypteris torresiana (Gaudich.) Ching (MT-EO), as well as its synergistic antibacterial effect in combination with commercial antibiotics. Fifty-seven compounds were identified in MT-EO, representing 97.9% of the total oil content. The compounds bicyclogermacrene (12.9%), spathulenol (11.9%), ß-elemene (5.7%), and hexyl hexanoate (5.0%) were detected as the main constituents. The microdilution and checkerboard assays were used to evaluate the antibacterial and synergistic properties of the essential oil. It was found that MT-EO possessed bactericidal activity against all tested bacteria, with MIC values between 0.625 to 1.250 mg/mL, which was the same as MBCs. Additionally, synergistic effects were detected in both M. torresiana essential oil -chloramphenicol and -streptomycin combinations. Besides, according to the MTT test, MT-EO possessed broadspectrum cytotoxicities on various cell lines with IC50 values ranging from 15.12 ± 0.96 to 47.07 ± 1.96 µg/mL, including the MCF-7, A-549, HCT-116, HepG2, and LO2 cell lines. Furthermore, MT-EO showed moderate antioxidant activities in DPPH, ABTS, and FRAP assays, with IC50 values of 434.5 ± 9.6 and 98.1 ± 1.1 µg/mL, and Trolox equivalent of 97.11 ± 3.37 µmol Trolox × g-1, respectively. [ABSTRACT FROM AUTHOR]

In response to the challenge of antibiotic-resistant microorganisms, oxazolone analogs are frequently used for bacterial, antiviral, and anti-inflammatory treatments. However, few studies have shown bis-oxazolone analogs possess antibacterial activities. In this study, we modified bis-oxazolone molecules with various aromatic amines to create new bis-benzamide and bis-imidazolone derivatives. These derivatives were analyzed using FTIR, 1H-NMR, and 1,3C-NMR spectroscopy. Molecular docking revealed favorable interactions with DNA gyrase, with compounds 3, 4a, and 5e showing higher binding affinities than penicillin G and ampicillin. These findings suggest their potential as future antimicrobial agents. The tested compounds demonstrated efficacy against bacterial strains, particularly E. coli and S. aureus, with significant activity observed in compounds 4a, 4e, 5d, and 5e. Antioxidant activity, assessed using the DPPH method, showed bis-compounds with excellent results comparable to ascorbic acid. This encourages further studies to explore their potential. Overall, the synthesized bis-oxazolone derivatives demonstrated increased medicinal activity and high potential as future antimicrobial and antioxidant agents. [ABSTRACT FROM AUTHOR]

Lately, antimicrobial resistance (AMR) is increasing at an exponential rate making it important to search alternatives to antibiotics in order to combat multi-drug resistant (MDR) bacterial infections. Out of the several antibacterial and antibiofilm strategies being tested, antimicrobial peptides (AMPs) have shown to give better hopes in terms of a long-lasting solution to the problem. To select a desired AMP, it is important to make right use of available tools and databases that aid in identification, classification, and analysis of the physiochemical properties of AMPs. To identify the targets of these AMPs, it becomes crucial to understand their mode-of-action. AMPs can also be used in combination with other antibacterial and antibiofilm agents so as to achieve enhanced efficacy against bacteria and their biofilms. Due to concerns regarding toxicity, stability, and bioavailability, strategizing drug formulation at an early-stage becomes crucial. Although there are few concerns regarding development of bacterial resistance to AMPs, the evolution of resistance to AMPs occurs extremely slowly. This comprehensive review gives a deep insight into the selection of the right AMP, deciding the right target and combination strategy along with the type of formulation needed, and the possible resistance that bacteria can develop to these AMPs. [ABSTRACT FROM AUTHOR]

In the present work, methanolic extracts from thyme and dittany plants were prepared and characterized in terms of their polyphenolic content through analytical and spectrophotometric techniques. Rosmarinic acid, thymol and carvacrol were found to be the main components of the extracts, which were further biologically assessed for their antioxidant, anti-tyrosinase, anti-lipase and antibacterial activity against Gram-negative and Gram-positive bacteria. As found, thyme extracts exhibited superior antioxidant activity (SC50 at 33.9 μg mL−1), while dittany extracts inhibited the microbial growth to a great extent against Bacillus subtilis strain (MIC at 0.5 mg mL−1) and E. coli strain (MIC at 2 mg mL−1). Furthermore, the thyme extract was proven to strongly inhibit the activity of lipase from Candida rugosa (IC50 at 63.9 μg mL−1), comparable to the standard inhibitor orlistat, while its inhibitory effect against mushroom tyrosinase was weak. On the other hand, the dittany extract presented an inhibitory effect against the tested lipase (IC50 over 500 μg mL−1) and an activation effect against tyrosinase (at concentrations > 500 μg mL−1). Additionally, molecular docking studies of the main compounds of the extracts showed that rosmarinic acid plays a crucial role on the inhibitory activity of the extracts against lipase, while thymol has a stronger effect on inhibiting tyrosinase. Furthermore, both extracts were employed in the preparation of gelatin-deep eutectic solvent (DES) hydrogels that were further studied for their antioxidant and antibacterial activity. The results showed that the incorporation of the extracts offered antibacterial properties to the biopolymer-based hydrogels and enhanced the antioxidant activity of gelatin up to 85%. [ABSTRACT FROM AUTHOR]

Among sixty-eight pseudomonads, isolate QCS59 from the rhizosphere of H. schimperi was selected based on its siderophore level. Production was optimal in Kings B supplemented with 2% peptone and 0.5% fructose at pH 6.5 and 25 °C for 72 h. Additionally, the threshold potential of iron was found at a concentration of 10 µM. After purification, the acidified siderophore presented a maximum absorption peak of 360 nm, while the neutral form presented a maximum of 414 nm, confirming its pyoverdine (PVD) nature. Furthermore, a major peak appeared at a retention time (RT) of 27.5 min during RP-HPLC, confirming its homogeneity. Interestingly, it demonstrated effective antibacterial activity, especially against Escherichia coli ATCC 8739, with a minimum inhibitory concentration (MIC) of 6.3 µg/mL and a minimum bactericidal concentration (MBC) of 12.5 µg/mL. At ½ the MIC value, it inhibited 82.1% of well-established biofilms of Salmonella enterica. There was an increase in malondialdehyde (MDA) and antioxidative enzymes, especially catalase (CAT) in the treated bacteria because of the peroxidation of membrane lipids and oxidative stress, respectively. SEM proved cellular lysis and surface malformation in most of the treated bacteria. This study concludes that QCS59 siderophore is a promising antibacterial candidate for treating wastewater bacteria and skin pathogens. [ABSTRACT FROM AUTHOR]

Sisymbrium irio Linn is one of the underutilized plants, well-known for its traditional importance in Unani Medicine. The present study aimed to evaluate the antibacterial activities of different polarity-based extracts made from seeds of S.irio (Indian variety). The antibacterial activity of 13 different solvent extracts of S.irio seeds was evaluated by the Agar well-diffusion method. Among 13 different solvent seed extracts, ethanolic extract inhibited the growth of all the three bacterial strains used in the study. Further GC-MS analysis of ethanolic extract was done to reveal its phytochemical constituents. Twenty-five different compounds were identified through GC-MS analysis of ethanolic extract of S.irio seeds. Subsequently, for performing in silico antibacterial studies, the identified phytochemicals were first tested for their drug-likeability through Molinspiration software which yielded four compounds. In silico virtual screening via Autodock Vina was done using four phytochemicals against DNA gyrase subunit B and Dihydrofolate reductase. Out of four phytochemical studied through in silico analysis, "Benzene-1,2-dicarboxylicacid, monoamide, N-(1-cyano-1-methylethyl)" was found to inhibit DNA gyrase subunit B most effectively. The present study revealed that Sisymbrium irio displayed potential antibacterial activity and can be used as a good source for designing potent antibacterial agents. [ABSTRACT FROM AUTHOR]

Polyurethane is a kind of synthetic polymer composed of isocyanates, polyols and chain extenders. Due to its excellent mechanical flexibility, biodegradability and physicochemical properties, polyurethane is widely used in biological, medical, food and antifouling fields. With the continuous development of science and technology, ordinary polyurethane materials have been unable to meet people's diverse and high standard aseptic requirements, and the development and application of antibacterial polyurethane is getting more and more attention. In this paper, the antibacterial modification methods of polyurethane materials were introduced, and the application status and antibacterial mechanism of polyurethane materials in medical treatment, food packaging, water treatment and other aspects in recent years were reviewed. At the end, the problems faced in the application of antibacterial polyurethane materials and corresponding improvement measures are discussed. [ABSTRACT FROM AUTHOR]

• Novel synthesis method. Ag-TiO 2 NPs are synthesized using chestnut extract as both a template and a reducing agent. • Multifunctional properties. The synthesized Ag-TiO 2 NPs possess excellent UV shielding, self-cleaning capacity, antibacterial ability, and antioxidant capacity. • Effective leather artifact preservation. This effective preservation strategy ensures the long-term protection of leather artifacts, safeguarding the cultural significance for future generations. The deterioration of leather artifacts can be caused by exposure to light, pollutants, microbes, and oxidation. In this work, silver-titanium dioxide nanoparticles (Ag-TiO 2 NPs) were synthesized using chestnut extract as both a template and a reducing agent, providing UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity. The results indicated that the addition of chestnut extract and Ag significantly enhanced the UV light shielding capability of Ag-TiO 2 NPs by enhancing the light absorption efficiency, as well as reduced the band gap from 3.20 eV to 2.82 eV, and improved the self-cleaning capability as evidenced by an increase in Congo red (CR) dye degradation rate from 26 % to 55 %. Additionally, Ag-TiO 2 NPs also exhibited remarkable antibacterial activity, as evidenced by a significant increase in the inhibition zone against bacteria, as well as enhanced antioxidant capability with the DPPH free radical scavenging capability increased from 22 % to 88 %. After Ag-TiO 2 NPs treatment, there was no obvious change in the appearance of leather, while the antibacterial activity of leather was significantly increased. The Ag-TiO 2 NPs produced through a green approach could offer robust UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity to prevent the deterioration of leather artifacts, making a significant contribution to the long-term preservation of cultural heritage. The green synthesis of Ag-TiO 2 NPs using chestnut extract as both a template and a reducing agent was conducted, with excellent UV light shielding, self-cleaning capacity, antibacterial activity, and antioxidant capacity for the long-term preservation of leather artifacts. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, we have investigated a strategy for designing some novel pyrazoline-thiazole hybrids containing azo moiety. The synthesized compounds were structurally characterized and their antibacterial activity was in vitro evaluated against gram-negative and gram-positive bacteria using the inhibition zone method. The antibacterial activity of the tested compounds was moderate to good. Compound 12c showed the best activity compared to the standard drug (Ampicillin) against S. aureus and E. coli at the concentration of 0.16 mg/mL, with the highest inhibition zone diameters of 34 mm and 37 mm, respectively. Moreover, in silico molecular docking and ADME profile studies were investigated in order to understand the binding affinity and interactions along with the ADME properties of all designed hybrids. Additionally, Density functional theory (DFT) calculations were carried out at the B3LYP/6-311G++ level of theory. The study involved an examination of the optimized geometry, molecular electrostatic potential map, and the HOMO → LUMO electronic energy gap. In accordance with the findings, the newly synthesized hybrids could be beneficial for medicine and exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

The urgency of multidrug-resistant (MDR) bacterial infections in wounds is a significant concern due to the high prevalence of MDR in healthcare settings. Black pigmented marine bacteria, strain PS1C, were isolated from marine sediment on Awur Beach Jepara, Central Java, Indonesia, and cultured in the laboratory. The aim of this research includes molecular identification of strain PS1C, extracting black pigment from strain PS1C, isolation of MDR bacteria from wounds, and evaluating the antibacterial activity of black pigment from strain PS1C against MDR bacteria isolates of wound infections. We examined the 16S rRNA gene sequences strain PS1C to identify the species. Then, the black pigment from PS1C was extracted using methanol: acetone (7:3) solvent. Antibacterial activity was evaluated against MDR bacteria from wounds with the microdilution method. A black-pigmented bacterium was isolated and identified as Pseudomonas aeruginosa PS1C. We found that the black pigment from P. aeruginosa PS1C can be developed as an antibacterial agent against the MDR bacterial isolate of wounds with MIC and MBC values of 6.25-12.5 mg/ml and 6.25-25 mg/ml, respectively. In conclusion, the study's findings highlight the potential of the extract of black pigment from P. aeruginosa PS1C as an antibacterial agent against wound-causing MDR bacteria and reinforce previous research into P. aeruginosa can be isolated from marine sources. Additional in vivo investigations and the identification of the antibacterial activity's mode of action are required. [ABSTRACT FROM AUTHOR]

Mg Ga alloys are considered highly potential biodegradable materials, owing to its good mechanical properties and appropriate corrosion resistance. However, it is still far from application due to the lack of biological evaluation. In the present study, biocompatibility, osteogenesis and antibacterial activity of extruded Mg–xGa (x = 1 and 5 wt%) alloys were investigated by in vitro cell culture experiments and in vivo implantation. The cell adhesion and proliferation of osteoblast precursor cells (MC3T3-E1) showed the excellent cytocompatibility of Mg–1Ga and poor cytocompatibility of Mg–5Ga. The osteogenic activity was evaluated and revealed that Ga3+ in the Mg–1Ga extract had the ability to enhance osteogenic differentiation through the facilitation of its early stages. In vivo studies in a rat femoral condyle model revealed that both Mg–1Ga and Mg–5Ga significantly promoted new bone formation without causing any adverse effects. Mg–5Ga exhibited a much higher corrosion rate in vivo than Mg–1Ga. Its osteogenic activity was better due to the rapid release of Mg2+ and Ga3+, but this caused premature structural integrity loss. Mg–1Ga and Mg–5Ga released Ga3+ to inhibit E. coli and S. aureus , with antibacterial rate increasing with Ga content. Our studies demonstrate that Mg–Ga alloys have the potential to be used as osteogenic and antibacterial implant materials. This study evaluates the biocompatibility, osteogenesis, and antibacterial activity of Mg–Ga alloys, which are promising biodegradable materials for medical applications. The study finds that Mg–1Ga exhibits excellent cytocompatibility and promotes osteogenic differentiation, facilitating the early stages of osteoblast precursor cell development. In vivo studies in a rat femoral condyle model reveal that Mg–1Ga and Mg–5Ga significantly promote new bone formation without causing any adverse effects. The antibacterial activity of both alloys is evaluated against E. coli and S. aureus , with the inhibition rate increasing with Ga content. These findings suggest that Mg–Ga alloys have the potential to serve as osteogenic and antibacterial implant materials, providing significant insights into the development of novel biomedical implants. [Display omitted] [ABSTRACT FROM AUTHOR]

Caulerpa racemosa, a type of green algae, has been studied for its potential health benefits, including antioxidant and antibacterial properties. The extraction of bioactive compounds from marine algae using green solvents like Deep Eutectic Solvents (DES) has gained interest due to their efficiency and environmental friendliness. This research aimed to determine the potential antioxidant activity of C. racemosa extract using DES solvents and different sonication times as an antibacterial against pathogenic bacteria. The research employed a Factorial Completely Randomized Design (CRD) with two variables: sonication time (10, 20, and 30 minutes) and different DES solvents (ethanol and ethylene glycol (1:20) with 90% aquades, and methanol and glycerol (1:10) with 90% aquades. The highest antioxidant activity was found in DES Methanol-Glycerol (36.39 mg TE/g dw), followed by DES Ethanol- Ethylene glycol (28.30 mg TE/g dw), both significantly different (p<0.05). The C. racemosa extract inhibited the growth of V. parahaemolyticus with an inhibition zone of 8.08 mm at 50 ppm and 13.13 mm at 1,000 ppm. For V. harveyi, inhibition started at 6.37 mm at 50 ppm, reaching 11.70 mm at 1,000 ppm. DES Methanol-Glycerol with a 10-minute sonication provided the highest antioxidant activity and effectively inhibited V. parahaemolyticus and V. harveyi. Extraction of C. racemosa with DES-MG solvent and varying sonication times influences its antioxidant activity and antibacterial properties. [ABSTRACT FROM AUTHOR]

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In this paper, a novel method is presented to enhance the antimicrobial properties of polyvinyl chloride (PVC) via plasma-induced grafting of quaternary ammonium (QA). The results show that the content of oxygen-containing functional groups on PVC surface is significantly increased after Ar-O2 plasma treatment, beneficially enhancing the thickness and adhesion of QA coating. Plasma treatment time critically affects the morphology of PVC surface, which is closely related to the number, depth and diameter of pit on the surface. With the increase of pits size, the PVC surface forms ridge-like protrusions. The coating formed by grafting QA maintains the morphology characteristics of plasma-treated PVC surface. Results of antibacterial test show that specimens have the best antibacterial activity when there are a high and sharp ridge-like structure of QA coating on the plasma-treated PVC surface. [ABSTRACT FROM AUTHOR]

This study introduces a sustainable and environmentally friendly method for synthesizing selenium nanoparticles (SeNPs) by using Calluna vulgaris as a reducing agent. The process involves the addition of Na2SeO3 to a C. vulgaris aqueous solution, followed by reduction with ascorbic acid. UV-Vis spectroscopy confirmed SeNP formation, with a distinct absorption peak at 289 nm. Morphological analysis via Scanning Electron Microscopy (SEM) revealed spherical nanoparticles below 100 nm, as corroborated by Transmission Electron Microscopy (TEM) images displaying sizes ranging from 42.91 to 66.93 nm. Energy Dispersive Spectroscopy (EDS) confirmed the presence of selenium. Antibacterial assessments demonstrated the efficacy of C.vulgaris Selenium Nanoparticles (Cv-SeNPs) against gram-positive (Enterococcus faecalis, Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). Cv-SeNPs exhibited notable antibacterial activity, particularly against E. Faecalis. In terms of antioxidant activities, Cv-SeNPs exhibited significant scavenging potential against DPPH and ABTS radicals, with low IC50 values of 24.72 and 16.87 µg/mL, respectively. The scavenging activities increased with concentration, reaching 86.6% for DPPH and 99.7% for ABTS at specific concentrations. The inclusion of ascorbic acid as a capping agent further augmented the free radical scavenging capabilities, indicating a synergistic relationship between selenium nanoparticles and capping agents. This research underscores the dual functionality of Cv-SeNPs as effective antibacterial agents and potent antioxidants. The green synthesis methodology utilizing C. vulgaris offers a sustainable approach for producing selenium nanoparticles with desirable characteristics, suggesting potential applications in medicine and industry. Further research on biomedical and industrial uses of Cv-SeNPs is needed. [ABSTRACT FROM AUTHOR]

Background: A green and efficient process, free from toxic solvents, was employed to prepare an α-mangostin-rich extract. Conventional techniques like maceration and heat reflux extraction are recognized for their time-intensive nature, as well as the requirement for significant quantities of organic solvents. This innovative process not only reduces energy consumption but also streamlines production steps, providing a more sustainable alternative in herbal medicine preparation. Purpose: The purpose of the study was to compare the antibacterial activities of alcohol disinfectants and α-mangostin extract-containing disinfectants against tested microorganisms. Materials and Methods: The α-mangostin-rich extract was obtained from dried powders of Garcinia mangostana pericarps utilizing the microwave-assisted extraction method with polyethylene glycol 400 (PEG 400). The α-mangostin content in the resultant extract was determined through the high-performance liquid chromatography (HPLC) method. Additionally, a broth microdilution method was utilized to investigate the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of each compound against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius. Results: According to a microdilution method, the disinfectant comprising isopropanol (50% and 70%) with 1% α-mangostin extract demonstrated antibacterial effectiveness against both MRSA and S. pseudintermedius. The MICs and MBCs were observed within dilutions ranging from 1:64 to 1:512 and 1:64 to 1:256, respectively. Ethanol (50% and 70%) plus 1% α-mangostin extract disinfectant exhibited antibacterial activity with MICs and MBCs at dilutions of 1:32–1:512 and 1:16–1:128, respectively. Moreover, isopropanol and ethanol (30%) with 1% α-mangostin extract disinfectant demonstrated antibacterial activity with MICs and MBCs at dilutions of 1:16–1:256 and 1:4–1:128, respectively. However, isopropanol (50% and 70%) and ethanol (50% and 70%) disinfectants showed weaker antibacterial activity than α-mangostin extract-containing alcohol solutions. Although isopropanol (30%) disinfectant demonstrated antibacterial activity (MICs and MBCs at dilutions of 1:16–1:32), the 30% ethanol solution did not show any activity against either bacterium. In addition, α-mangostin extract exhibited stronger antibacterial activity (MICs and MBCs at dilutions of 1:625–1:5,000) than all alcohol solutions. Conclusion: The combination of isopropanol and ethanol disinfectants with α-mangostin-rich extract exhibited significant antibacterial effectiveness against MRSA and S. pseudintermedius. The enhancement of efficacy by α-mangostin-rich extract suggests promising opportunities for enhancing disinfection approaches. [ABSTRACT FROM AUTHOR]

In this study, a film was prepared from polyvinyl alcohol (PVA) and zinc oxide (ZnO) nanoparticles (nano-ZnO) via the casting method. Nanoparticles were added to PVA biopolymer to create reinforced biocomposite films with different loading contents (2, 4, and 6 wt.%), and they were tested by performing the following assays: the FTIR test, the antibacterial, soil burial test, DSC, AFM, and SEM. The results showed an improvement of the membranes in the antibacterial properties for both Escherichia coli (E. coli, Gram-negative) and Staphylococcus aureus (S. aureus, Gram-positive) when nano-ZnO was added. The biodegradation through weight loss was observed for all samples, and the results showed that the weight loss increased with the increase in ZnO nanoparticle content from 2% to 6% wt. The DSC results showed that the addition of ZnO led to an increase in Tg, and increasing the degree of glass transition led to an increase in the degradation rate. In the FTIR results, only physical interference was observed; no chemical interference was evident. The AFM results showed some agglomerations of nano-ZnO in the PVA matrix led to an increase in the surface roughness of the PVA/nano-ZnO film. [ABSTRACT FROM AUTHOR]

This study investigated the antioxidant and antibacterial activities of Tapuy lees, a traditional rice wine fermentation by-product rich in anthocyanins. The crude methanolic and anthocyanin-rich fractions were evaluated for phytoconstituents and were subjected to antioxidant and antibacterial assays. Results showed various phytochemicals, including tannins, flavonoids, and anthocyanins. The methanolic extract exhibited substantial phenolic content. Meanwhile, the anthocyanin-rice aqueous fraction revealed the highest antioxidant activities against DPPH, superoxide, and hydroxyl radicals. Additionally, both extracts demonstrated antibacterial activity against Escherichiacoli and Staphylococcusaureus, with the anthocyanin-rich fraction displaying superior efficacy. Specifically, the anthocyanin-rich fraction displayed larger zones of inhibition against both bacterial strains compared to the methanolic extract. These results suggest the potential of the anthocyanin-rich aqueous fraction of tapuy lees as a natural antibacterial agent, indicating its potential application in food and health industries. Further in vitro and in vivo studies are recommended to validate and complement these preliminary findings, paving the way for developing novel functional food products derived from waste. [ABSTRACT FROM AUTHOR]

One of the main sources of novel chemicals with possible medical use is medicinal plants. Multiple diseases have been treated with them in traditional medicine. The purpose of this study was to explore the phytochemical characteristics, antioxidant effects, and antibacterial activities of several extracts of Ziziphus lotus fruits (ZLF). Phytochemical analysis of ZLF extracts revealed the presence of several bioactive molecules such as phenolic compounds and alkaloids. Water, methanol 50%, methanol 80%, methanol, ethanol, and hexane are the 6 different solvents which were used in order to evaluate the phytochemical profile as well as the biological activities of ZLF, and whose aqueous extract showed the best results. The aqueous extract had the highest yield, followed by methanol, ethanol, and lastly hexane (p < 0.05). The aqueous extract showed the highest total contents of phenols, flavonoids, and tannins (77.13 ± 0.11 mg GAE/g DM, 33.36 ± 0.51 mg QE/g DM, and 03.72 ± 0.16 mg CE/g DM respectively), while the Hexane extract revealed the lowest contents (12.36 ± 0.26 mg GAE/g DM, 06.20 ± 0.23 mg QE/g DM, and 01.20 ± 0.10 mg CE/g DM respectively). By using the DPPH, ABTS, and FRAP methods, and for the aqueous extract, ZLF extracts demonstrated considerable antioxidant capacities, with the values IC50 = 37 ± 0.27, IC50 = 67 ± 0.18 and IC0.5 = 31 ± 0.22 respectively. All of the ZLF extracts, with the exception of the hexanic extract on Staphylococcus aureus, showed antibacterial efficacy against the bacterial strains of Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The results obtained reveal that ZLF exhibit significant biochemical composition and considerable biological activities encouraging its nutritional and therapeutic use. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has long been considered an effective way to tackle antibiotic resistance. Here, Methylene blue (MB) as photosensitizer was combined with carbon quantum dots (CQDs) as drug carriers to make a compound antibacterial agent. The fluorescent CQDs were prepared by hydrothermal method with citric acid (CA) and neutral red (NR) as raw materials. The CQDs can emit 640nm red fluorescence under 520nm laser irradiation. In the antibacterial experiment, CQDs-MB was irradiated with 660nm light. The results showed that CQDs-MB had ideal antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with 100% antibacterial concentration of 5μM and 10μM, respectively. The combination of CQDs and MB enhanced singlet oxygen (1O2) generation and the PDT activity of MB, which significantly increased the phototoxicity of MB to bacteria. [ABSTRACT FROM AUTHOR]

Synthesis of novel (E)‐N‐(4‐(substituted)benzylidene)‐6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides was achieved by the condensation of 6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides with substituted benzaldehydes in alcoholic medium in the presence of acetic acid. The structures of synthesized compounds are assigned on the basis of FT IR, 1H NMR, 13C NMR and Mass Spectral data. The compounds are subjected for their antibacterial, antifungal and DFT studies. Compounds, (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamide (5 b), (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 f), and (E)‐6‐chloro‐N‐(4‐hydroxybenzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 j) possessed pronounced antibacterial and antifungal activities due to their chemical structure. [ABSTRACT FROM AUTHOR]

One of the most common bacteria that cause nosocomial infections is Klebsiella pneumonia (K. pneumoniae), especially in patients who are very sick and admitted to the intensive care unit (ICU). The frequency of multi-drug-resistant Klebsiella pneumoniae (MDRKP) has dramatically increased worldwide in recent decades, posing an urgent threat to public health. The Western world's bacteriophage (phage) studies have been revitalized due to the increasing reports of antimicrobial resistance and the restricted development and discovery of new antibiotics. These factors have also spurred innovation in other scientific domains. The primary agent in phage treatment is an obligately lytic organism (called bacteriophage) that kills the corresponding bacterial host while sparing human cells and lessening the broader effects of antibiotic usage on commensal bacteria. Phage treatment is developing quickly, leading to many clinical studies and instances of life-saving medicinal use. In addition, phage treatment has a few immunological adverse effects and consequences in addition to its usefulness. Since K. pneumoniae antibiotic resistance has made treating multidrug-resistant (MDR) infections challenging, phage therapy (PT) has emerged as a novel therapeutic strategy. The effectiveness of phages has also been investigated in K. pneumoniae biofilms and animal infection models. Compared with antibiotics, PT exhibits numerous advantages, including a particular lysis spectrum, co-evolution with bacteria to avoid the emergence of phage resistance, and a higher abundance and diversity of phage resources than found in antibiotics. Moreover, phages are eliminated in the absence of a host bacterium, which makes them the only therapeutic agent that self-regulates at the sites of infection. Therefore, it is essential to pay attention to the role of PT in treating these infections. This study summarizes the state of knowledge on Klebsiella spp. phages and provides an outlook on the development of phage-based treatments that target K. pneumoniae in clinical trials. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance has emerged as a significant danger to global health, and the need for more effective antimicrobial resistance (AMR) control has been highlighted. Cinnamic acid is abundant in plant products and is a potential starting material for further modification, focusing on the development of new antimicrobial compounds. In the following review, we describe the classification of critical antibacterial-guided reactions applied to the main skeleton structure of cinnamic acid derivatives over the last decade. Of all of the main parts of cinnamic acids, the phenyl ring and the carboxylic group significantly affect antibacterial activity. The results presented in the following review can provide valuable insights into considerable features in the organic modification of cinnamic acids related to antibacterial medication development and the food industry. [ABSTRACT FROM AUTHOR]

Microbial contamination poses a serious threat to human health and socioeconomics, and is a major problem for global public health. Herein, we fabricated Ti 3 C 2 T x /ZnONPs composite by using Lactobacillus plantarum fermentation broth to reduce ZnONPs in situ on few-layer Ti 3 C 2 T x MXene after etching and delamination treatment. Antibacterial experiments showed that the Ti 3 C 2 T x /ZnONPs composite exhibited significant antibacterial and antibiofilm activity against both Gram-negative E. coli and Gram-positive S. aureus. Moreover, the exploration of the antibacterial mechanisms demonstrated that Ti 3 C 2 T x /ZnONPs could inhibit and kill bacteria by disrupting bacterial cell wall/membrane, causing leakage of intracellular contents, interfering with metabolism and inducing oxidative stress. The synergistic effect of multiple antibacterial mechanisms can effectively prevent the evolution of resistance. Overall, as a novel inorganic antibacterial material, Ti 3 C 2 T x /ZnONPs composite holds a promising application in the antimicrobial field. [Display omitted] • Ti 3 C 2 T x /ZnONPs were prepared by a green in-situ synthesis method. • Ti 3 C 2 T x /ZnONPs possess excellent broad-spectrum antimicrobial activity. • The antibacterial mechanism of Ti 3 C 2 T x /ZnONPs has been explored. • Ti 3 C 2 T x /ZnONPs have good biocompatibility and broad application prospects. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A type of unique azole‐hybridized acylhydrazonyl aloe emodins (AAEs) were developed as new antibacterial agents for combating bacterial infections. Some target AAEs showed strong antibacterial activities, especially, tetrazolylthioether AAE 27a exhibited broad antibacterial spectrum with 16—256 folds and 8—64 folds more active antibacterial efficacy than the reference drugs aloe emodin and norfloxacin, respectively. Tetrazolylthioether AAE 27a also gave low hemolysis and cytotoxicity, as well as favorable bioavailability. Preliminary mechanism explorations revealed that tetrazolylthioether AAE 27a could cause bacterial membrane depolarization and damage the cell membrane, resulting in nucleic acid leakage. Moreover, compound 27a could intercalate into DNA to impede its replication and form supramolecular 27a‐DNA gyrase complex to disturb the function of DNA gyrase. These findings would provide valuable insights for the further exploration of azolyl acylhydrazonyl aloe emodins as new potential antibacterial candidates. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) has been emerging as a major global health threat and calls for the development of novel drug candidates. Metal complexes have been demonstrating high efficiency as antibacterial agents that differ substantially from the established types of antibiotics in their chemical structures and their mechanism of action. One strategy to exploit this potential is the design of metal-based hybrid organometallics that consist of an established antibiotic and a metal-based warhead that contributes an additional mechanism of action different from that of the parent antibiotic. In this communication, we describe the organometallic hybrid antibiotic 2c, in which the drug metronidazole is connected to a gold(I) N-heterocyclic carbene warhead that inhibits bacterial thioredoxin reductase (TrxR). Metronidazole can be used for the treatment with the obligatory anaerobic pathogen Clostridioides difficile (C. difficile), however, resistance to the drug hampers its clinical success. The gold organometallic conjugate 2c was an efficient inhibitor of TrxR and it was inactive or showed only minor effects against eucaryotic cells and bacteria grown under aerobic conditions. In contrast, a strong antibacterial effect was observed against both metronidazole-sensitive and -resistant strains of C. difficile. This report presents a proof-of-concept that the design of metal-based hybrid antibiotics can be a viable approach to efficiently tackle AMR. A metronidazole-gold hybrid metalloantibiotic with high efficacy against resistant C. difficile [ABSTRACT FROM AUTHOR]