Strong Antibacterial Activity Research Articles

Antibacterial, Antioxidant and Cytotoxicity Assessment of Crassocephalum crepidioides Leaf Extract

The goal of the present investigation was to demonstrate the antibacterial activity of different solvent extracts (methanol, ethanol, cold aqueous and hot aqueous) of Crassocephalum crepidioides against ATCC bacterial cultures of Staphylococcus aureus, Escherichia coli, Methicillin resistant Staphylococcus aureus, Pseudomonas aeruginosa and its antioxidant potential. Furthermore, the chemical constituents present in the extract was perused by Gas chromatography-mass spectroscopy (GC-MS), along with in vitro cytotoxicity assessment. All the extracts were shown to be sensitive against S. aureus, MRSA and P. aeruginosa except for the ethanolic extract which was resistant to P. aeruginosa. Of all the extracts, hot aqueous extract found to be the most effective. It was found that Minimum inhibitory concentration (MIC) value of hot aqueous extract against S. aureus, MRSA and P. aeruginosa were 5 mg/mL, 5 mg/mL and 40 mg/mL, respectively. DPPH results showed that C. crepidioides leaf extract has potent antioxidant activity with IC50 value of 57.9 µg/mL. 22 compounds were detected in hot aqueous extract through Gas chromatography-mass spectroscopy. The results of the cytotoxicity evaluation displayed that the IC50 value of the hot aqueous extract of C. crepidioides on Vero cell lines was 292 µg/mL. This study concludes that C. crepidioides leaf extract is non-toxic, has various bioactive components and strong antibacterial and antioxidant activities, thus making it a promising therapeutic agent for various biomedical applications.

Isolation and Characterization of a Novel Escherichia Bacteriophage with Potential to Control Multidrug-Resistant Avian Pathogenic Escherichia coli and Biofilms

Background/Objectives: Avian pathogenic Escherichia coli (APEC) infection is a significant problem for the global chicken industry, as it decreases animal welfare and is associated with substantial economic losses. Traditionally, APEC infections have been controlled through the use of antibiotics, which has led to an increased prevalence of antibiotic-resistant E. coli. Therefore, developing alternative treatments for APEC infection is crucial. Methods: In this study, an Escherichia phage specific to multidrug-resistant (MDR) APEC, designated as phage vB_EcoP_PW8 (phage vECPW8), was isolated. The morphology, phage adsorption to host cells, one-step growth curve, thermal stability, pH stability, whole-genome sequencing, antibacterial ability, and antibiofilm efficacy of phage vECPW8 were evaluated. Results: The results demonstrated that phage vECPW8 has a Podoviridae morphology and is effective at lysing bacteria. Phage vECPW8 exhibited a high absorption rate to bacterial cells (more than 85% within 10 min) and had a latent period of 20 min, with a burst size of 143 plaque-forming units per cell. Additionally, phage vECPW8 showed good temperature and pH stability. The phage displayed strong antibacterial activity in vitro, and its efficacy in controlling bacteria was confirmed through scanning electron microscopy. Whole-genome sequencing revealed that the phage has a linear genome with 69,579 base pairs. The genome analysis supported the safety of the phage, as no toxin, virulence, or resistance-related genes were detected. Phage vECPW8 was identified as a novel lytic phage in the Gamaleyavirus genus and Schitoviridae family. The phage also demonstrated antibiofilm efficacy by reducing and preventing biofilm formation, as evidenced by biofilm biomass and bacterial cell viability measurements. Conclusions: These results indicate that phage vECPW8 is a promising candidate for the effective treatment of MDR APEC infections in poultry.

Antibacterial Activity and Antifungal Activity of Monomeric Alkaloids

Scientists are becoming alarmed by the rise in drug-resistant bacterial and fungal strains, which makes it more costly, time-consuming, and difficult to create new antimicrobials from unique chemical entities. Chemicals with pharmacological qualities, such as antibacterial and antifungal elements, can be found in plants. Alkaloids are a class of chemical compounds found in nature that mostly consist of basic nitrogen atoms. Biomedical science relies heavily on alkaloid compounds. Based on 241 papers published in peer-reviewed scientific publications within the last ten years (2014–2024), we examined 248 natural or synthesized monomeric alkaloids that have antifungal and antibacterial activity against Gram-positive and Gram-negative microorganisms. Based on their chemical structure, the chosen alkaloids were divided into four groups: polyamine alkaloids, alkaloids with nitrogen in the side chain, alkaloids with nitrogen heterocycles, and pseudoalkaloids. With MIC values of less than 1 µg/mL, compounds 91, 124, 125, 136–138, 163, 164, 191, 193, 195, 205 and 206 shown strong antibacterial activity. However, with MIC values of below 1 µg/mL, compounds 124, 125, 163, 164, 207, and 224 demonstrated strong antifungal activity. Given the rise in antibiotic resistance, these alkaloids are highly significant in regard to their potential to create novel antimicrobial drugs.

Fabrication of Multifunctional Green-Synthesized Copper Oxide Nanoparticles Using Rumex vesicarius L. Leaves for Enhanced Photocatalytic and Biomedical Applications

Recently, the use of plant extracts has emerged as an innovative approach for the production of various nanoparticles. Enhancing green methods for synthesizing copper oxide (CuO) nanoparticles (NPs) is a key focus in the field of nanotechnology. This study presents a novel and eco-friendly synthesis of CuO NPs using Rumex vesicarius L. leaf extracts, offering a cost-effective and efficient method. The synthesized CuO NPs were evaluated for their cytotoxic effects against human cervical carcinoma (HeLa) cells, as well as their photocatalytic and antimicrobial activities. The morphology, size, and structural properties of the CuO NPs were characterized using various analytical techniques. X-ray diffraction (XRD) analysis confirmed the pure crystalline structure of the CuO NPs with a size of 19 nm, while transmission electron microscopy (TEM) showed particle sizes ranging from 5 to 200 nm. The photocatalytic performance of the CuO NPs was assessed through the photodegradation of crystal violet (CV) and methylene blue (MB) dyes under UV light. The NPs exhibited excellent decolorization efficiency, effectively degrading dyes in aqueous solutions under irradiation. Furthermore, the green-synthesized CuO NPs displayed strong antibacterial and antifungal activities against a variety of human pathogens. They also demonstrated significant dose-dependent cytotoxicity against the HeLa cancer cell line, with an IC50 value of 8 ± 0.54 μg/mL.

A case report of severe drug-induced immune hemolytic anemia caused by piperacillin

Piperacillin is a beta-lactamase inhibitor frequently used in the treatment of urinary tract infections. It is a broad-spectrum antibiotic with strong antibacterial action against Pseudomonas aeruginosa and Enterobacter, especially extended-spectrum beta-lactamase-producing Enterobacteria and Enterococcus. Side effects of piperacillin include allergic reactions, rashes such as urticaria, leukopenia, interstitial nephritis, asthma attacks, serological reactions, candida infection, and bleeding with more severe reactions resulting in anaphylactic shock. Anemia and hemolytic anemia are rare adverse reactions to piperacillin, with an incidence of 0.01–0.10%. We report herein the case of a severe postoperative immune hemolytic reaction to piperacillin. Fortunately, we quickly recognized and identified the drug reaction caused by piperacillin, immediately stopped the use of piperacillin, and performed a blood transfusion. The patient recovered and was subsequently discharged from the hospital.

Antibacterial, Herbicidal, and Plant Growth-Promoting Properties of Streptomyces sp. STD57 from the Rhizosphere of Adenophora stricta

Bacterial wilt triggered by the soil-borne pathogenic bacterium Ralstonia solanacearum is one of the most serious diseases in tomato plants, leading to huge economic losses worldwide. Biological control is considered an environmentally friendly and sustainable way to manage soil-borne diseases. In this study, Streptomyces sp. STD57 isolated from the rhizosphere of Adenophora stricta showed strong antibacterial activity against R. solanacearum. Pot experiments showed that strain STD57 exhibited a significant biocontrol effect (81.7%) on tomato bacterial wilt in the greenhouse environment. Furthermore, strain STD57 could inhibit the growth of weeds (Amaranthus retroflexus, Portulaca oleracea, and Echinochloa crusgalli) but promote the growth of crops (wheat, rice, and tomato). The plant growth-promoting substance was identified as indoleacetic acid (IAA) by high-pressure liquid chromatography–mass spectrometry and genome analysis. Coarse separation of the fermented extracts revealed that the antibacterial and herbicidal substances were mainly in the fermentation supernatant and belonged to different products. These findings suggested that strain STD57 may be a potential biocontrol and bioherbicide agent useful in agriculture.

Antibacterial and Photocatalytic Applications of Silver Nanoparticles Synthesized from Lacticaseibacillus rhamnosus.

The biosynthesis of silver nanoparticles (AgNPs) presents an innovative and sustainable approach in nanotechnology with promising applications in fields such as medicine, food safety, and pharmacology. In this study, AgNPs were successfully synthesized using the probiotic strain Lacticaseibacillus rhamnosus (BCRC16000), addressing challenges related to stability, biocompatibility, and scalability that are common in conventional nanoparticle production methods. The formation of AgNPs was indicated by a color change from yellow to brown, and UV-visible spectrophotometry confirmed their presence with a characteristic absorption peak at 443 nm. Furthermore, Fourier transform infrared (FTIR) spectroscopy revealed the involvement of biomolecules in reducing silver ions, which suggests their role in stabilizing the nanoparticles. In addition, field emission scanning electron microscopy (FE-SEM) showed significant morphological and structural changes. At the same time, dynamic light scattering (DLS) and zeta potential analyses provided valuable insights such as average size (199.7 nm), distribution, and stability, reporting a polydispersity index of 0.239 and a surface charge of -36.3 mV. Notably, the AgNPs demonstrated strong antibacterial activity and photocatalytic efficiency, underscoring their potential for environmental and biomedical applications. Therefore, this study highlights the effectiveness of Lacticaseibacillus rhamnosus in the biosynthesis of AgNPs, offering valuable antibacterial and photocatalytic properties with significant industrial and scientific implications.

Mucus-Penetrable Biomimetic Nanoantibiotics for Pathogen-Induced Pneumonia Treatment.

Bacterial pneumonia has garnered significant attention in the realm of infectious diseases owing to a surge in the incidence of severe infections coupled with the growing scarcity of efficacious therapeutic modalities. Antibiotic treatment is still an irreplaceable method for bacterial pneumonia because of its strong bactericidal activity and good clinical efficacy. However, the mucus layer forming after a bacterial infection in the lungs has been considered as the "Achilles' heels" facing the clinical application of such treatment. Herein, traceable biomimetic nanoantibiotics (BioNanoCFPs) were developed by loading indacenodithieno[3,2-b]thiophene (ITIC) and cefoperazone (CFP) in nanoplatforms coated with natural killer (NK) cell membranes. The BioNanoCFP exhibited excellent demonstrated mucus-penetrating abilities, facilitating their arrival at the infection site. The presence of Toll-like receptors in the NK cell membrane rendered the BioNanoCFP with the capability to recognize pathogen-associated molecular patterns within bacteria, allowing precise targeting of bacterial colonization sites and achieving substantial therapeutic efficacy. Overall, our findings demonstrate the viability and desirability of using NK cell membrane-mediated drug delivery as a promising strategy for precision treatment.

The Composition, Antioxidant and Antibacterial Activity of Essential Oils from Five Species of the Magnoliaceae Family.

The leaves of Magnoliaceae family plants contain abundant essential oils (EOs), and these species can be used in many fields due to their high industrial, medicinal, and ornamental values. This study aims to identify the main compounds of the EOs from the leaves of five common Magnoliaceae species (Michelia maudiae, Michelia hedyosperma, Michelia macclurei, Manglietia lucida, Manglietia conifer) using hydrodistillation, GC-MS analysis, and in vitro tests. Additionally, the antioxidant and antibacterial activities of the EOs were also evaluated. The results show that 151 compounds were identified across five species, with sesquiterpenes being dominant. Some key compounds (such as β-caryophyllene, δ-amorphene, β-guaiene, globulol, and β-acorenol) were common among all the species, highlighting their crucial roles in plant physiology and resilience. Other compounds (like valeranone and nerolidol in M. maudiae and β-elemene in M. macclurei) were specific, indicating different functions. Among the five species, the essential oil of M. macclurei contains β-elemene and nerolidyl acetate, and it has the weakest antioxidant activity (IC50 value: 2918.61~21,341.98 μg/mL) but the strongest antibacterial activity (inhibition zone diameter: 8.55 ± 0.93~22.92 ± 0.46 mm; LC50 value: 0.02~0.78 mg/mL). Meanwhile, the EO of M. maudiae demonstrated the best antioxidant activity (the IC50 value was 1283.58~6258.32 μg/mL) and the second-best antibacterial activity (the inhibition zone diameter ranged from 7.61 ± 0.02 to 26.92 ± 0.46 mm, and the LC50 value was 0.03~2.28 mg/mL). Overall, the EO of M. maudiae had the best comprehensive performance. Therefore, the EOs of M. macclurei and M. maudiae showed different performances in biological activity categories, and they could be developed and used in different fields, with the possibility of discovering new applications. This brings inspiration to the potential commercial and industrial uses of sesquiterpenes in Magnoliaceae.

Multi-functional polysaccharides composite film containing cashew and jik leaf carbon dots: Properties and bioactivities

Carbon dots (CDs) from the leaf powders of cashew (C-CDs), jik (J-CDs) and the mixed cashew/jik (1:1) (CJ-CDs) using hydrothermal method were synthesized and characterized. All three CDs were incorporated into chitosan/starch composite (CS) film at the level of 3 % (w/w). Microstructure images revealed that all films had slight differences in surface and internal structure. Thickness of the CS film increased with the inclusion of fillers (CDs). Inclusion of CDs slightly reduced the tensile and water vapor barrier properties of the CS film. CS film containing C-CDs exhibited the improved elasticity, UV barrier and antioxidant activity among all the films tested. Color and opaqueness of the resulting films were governed by the yellowish CDs. Distinctive peaks of resulting CS film were detected in FTIR spectra, while all CDs had no marked effect on the spectra. The release of CDs from films was more pronounced in water than in alcoholic solutions (10–95 % ethanol). Strongest antibacterial activities against Listeria monocytogenes and Escherichia coli were recorded for CDs added film, in which the highest activities were found for CS/CJ-CDs film. Thermal stability was also enhanced in CS/CJ-CDs film. Thus, the CS film loaded with CDs, especially from the mixture of cashew and jik leaf powders could serve as a promising active packaging for inactivation of some pathogens in food products.

Antibacterial activity of cell-free supernatant produced by Lactobacillus coryniformis 7841 against Vibrio parahaemolyticus and its potential application in salmon preservation

In this study, a strain of lactic acid bacteria, whose cell-free supernatant (CFS) exhibited strong antibacterial activity against Vibrio parahaemolyticus, was isolated from traditional Chinese fermented vegetables and identified as Lactobacillus coryniformis 7841 (LC7841) based on morphological, biochemical, and molecular characteristics. The minimum bactericidal concentration and minimum inhibitory concentration of the 10-fold cell-free supernatant concentrate (CFSC) were both 10 μL/mL against V. parahaemolyticus. CFSC caused cell wall and membrane disruption of V. parahaemolyticus validated by the increasing leakages of intracellular substances (nucleic acids, proteins, and β-galactosidase), alkaline phosphatase and the accumulation of malondialdehyde. In further, scanning electron microscopy, transmission electron microscopy, and live-dead cell observation by confocal laser scanning microscope revealed that CFSC caused cell wall and membrane damages in V. parahaemolyticus in a concentration-dependent manner. The composite films incorporating CFSC in chitosan-gelatin based films were applied for salmon preservation. The composite films significantly inhibited the propagation of V. parahaemolyticus, decreased the decay rate, and prolonged the shelf-life of salmon. Consequently, these results indicated that CFC of LC7841 may have potential applications as biopreservatives against Vibrio-related contamination in seafood.

Development and characterization of antibacterial marine extract-infused cellulose acetate nanofibers as wound dressings for combatting multidrug-resistant wound infections

Wound infections caused by multidrug-resistant bacteria pose a significant challenge globally in healthcare. Traditional wound dressings often lack efficacy against these resilient pathogens, necessitating the exploration of innovative approaches to combat infections and promote wound healing. This study was designed to investigate a novel wound dressing marine extract-infused electrospun cellulose acetate nanofibers (CANF) with particular emphasis on combating multidrug-resistant bacteria. Cellulose acetate solutions were combined with marine extract (Heteroxenia Fuscescens soft coral, H. Fu) before the creation of electrospun nanofibers. The antibacterial activities of H. Fu extract and the prepared nanofiber mats were explored against Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, and Staphylococcus epidermidis. Furthermore, the antibacterial properties of the crude H. Fu extract were directly assessed, showing potent activity against several pathogens. Results displayed that H. Fu extract has a robust antibacterial action against tested bacteria. Different concentrations of H. Fu (0.05 g, 0.1 g, 0.2 g, and 0.3 g) were added to CA solution, and named as H. Fu-1@CANF, H. Fu-2@CANF, H. Fu-3@CANF and H. Fu-4@CANF, respectively. The obtained results from SEM analysis demonstrated the smooth and uniform fibers. As observed, the addition of H. Fu with specific concentrations (0.05 g, 0.1 g, 0.2 g) has no significant impact on the smooth properties of the formed nanofibers. Increasing the concentration of H. Fu (0.3 g) leads to the formation of nanofibers coated with huge beads. FTIR affirmed the existence of H. Fu that blended with CANF. The hydrophilicity of the formed CANF was significantly enhanced thanks to the presence of H. Fu extract. The contact angle values of CANF, H. Fu-1@CANF, H. Fu-2@CANF, and H. Fu-3@CANF were 33.3°, 57.1°, 60.8° and 62.9°, respectively. The mechanical properties in terms of ultimate force (kg) recoded values were 0.89, 0.95, 1.2, 1.3 for CANF, H. Fu-1@CANF, H. Fu-2@CANF and H. Fu-3@CANF, respectively, those of CNF were markedly enhanced when loaded with H. Fu. This study evaluates the antibacterial efficacy of nanofiber mats loaded with H. Fu extract against common cutaneous bacterial pathogens. Four nanofiber samples were tested for their inhibitory impact on bacterial survival counts using the disc diffusion method. Important results from the study include the observation that H. Fu-3@CANF exhibited the largest zones of inhibition (ZOI) with diameters of 35 ± 0.25 mm for P. aeruginosa, 32 ± 0.65 mm for A. baumannii, 28 ± 0.14 mm for S. aureus, and 27.6 ± 0.48 mm for S. epidermidis. Additionally, the H. Fu-2@CANF sample demonstrated strong antibacterial activity, with ZOI diameters of 32 ± 0.56 mm, 29 ± 0.81 mm, 26 ± 0.27 mm, and 25.4 ± 0.28 mm for the respective bacteria. The Microtox® assay further evaluated the toxicity levels of the nanofiber mats, revealing that while all samples exhibited some toxicity, the H. Fu-3@CANF sample had the lowest toxicity profile. These findings highlight the potential of H. Fu-loaded nanofibers, particularly H. Fu-3@CANF, for broad-spectrum antibacterial applications. The study underscores the importance of incorporating bioactive compounds into nanofiber mats to enhance their antimicrobial properties, making them suitable candidates for medical and environmental applications requiring effective bacterial eradication.

A dissolving microneedle patch loaded with plumbagin/hydroxypropyl-β-cyclodextrin inclusion complex for infected wound healing

Treating infected wounds is facing a serious challenge due to the rapid spread of antibiotic resistance worldwide. In the search for novel antimicrobial drugs, natural products often serve as a crucial resource. Plumbagin (PLB) is the most important natural active ingredient in the root of Plumbago zeylanica L. known for its excellent antibacterial ability. However, the application of PLB is limited because of its poor water solubility, instability, and tendency to sublimate. In this study, we propose a solution by designing a hyaluronic acid (HA)/polyvinylpyrrolidone (PVP) dissolving microneedle patch loaded with PLB/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex. PLB was encapsulated into the cavity of HP-β-CD to improve its solubility and stability using the neutralization agitation method. The formation of the inclusion complex significantly increased the water solubility of PLB to 1350 ± 6.8 μg/mL, which is 17 times higher than its original value of 79.3 ± 1.7 μg/mL. The encapsulation efficiency was found to be 94.82 ± 3.34%. In vitro drug release studies, PLB microneedles loaded with PLB/HP-β-CD inclusion complex rapidly released into PBS within 15min. Furthermore, the PLB microneedles exhibited strong antibacterial activity against Staphylococcus aureus (S. aureus) both in vivo and in vitro. They also remarkably accelerated the healing of infected wounds in mice by enhancing collagen deposition and re-epithelialization, reducing inflammation, and stimulating angiogenesis. Overall, this multifunctional microneedle patch shows promising potential for clinical applications in the healing of infected wounds.

Naturally derived 3-aminoquinuclidine salts as new promising therapeutic agents

Quaternary ammonium compounds (QACs) are a biologically active group of chemicals with a wide range of different applications. Due to their strong antibacterial properties and broad spectrum of activity, they are commonly used as ingredients in antiseptics and disinfectants. In recent years, the spread of bacterial resistance to QACs, exacerbated by the spread of infectious diseases, has seriously threatened public health and endangered human lives. Recent trends in this field have suggested the development of a new generation of QACs, in parallel with the study of bacterial resistance mechanisms. In this work, we present a new series of quaternary 3-substituted quinuclidine compounds that exhibit potent activity across clinically relevant bacterial strains. Most of the derivatives had minimal inhibitory concentrations (MICs) in the low single-digit micromolar range. Notably, QApCl and QApBr were selected for further investigation due to their strong antibacterial activity and low toxicity to human cells along with their minimal potential to induce bacterial resistance. These compounds were also able to inhibit the formation of bacterial biofilms more effectively than commercial standard, eradicating the bacterial population within just 15 min of treatment. The candidates employ a membranolytic mode of action, which, in combination with the generation of reactive oxygen species (ROS), destabilizes the bacterial membrane. This treatment results in a loss of cell volume and alterations in surface morphology, ultimately leading to bacterial cell death. The prominent antibacterial potential of quaternary 3-aminoquinuclidines, as exemplified by QApCl and QApBr, paves the way for new trends in the development of novel generation of QACs.

Ag enhanced CuS nanoflower catalyst coupling dielectric barrier discharge plasma for disinfection performance and mechanism

In this study, the hydrothermal method was employed to grow submicron CuS on carbon cloth (CC), and the photoreduction method was used to grow Ag nanoparticles on the CuS submicron flowers, thus forming the Ag/CuS/CC catalytic electrode. The application of Ag/CuS/CC electrode-coupled dielectric barrier discharge (DBD) plasma in the disinfection of pathogenic bacteria in water was studied. The Ag/CuS/CC electrode exhibits strong antibacterial activity, and under an external voltage of 30 V, the degradation efficiency of Bacillus subtilis reaches 99.99% within 15 min without regeneration. After five cycles, the inactivation rate of Bacillus subtilis reached 99.99% within 25 min. The practical applicability of the Ag/CuS/CC-coupled DBD system for treating actual wastewater was evaluated, and the changes in biological toxicity were investigated. The results indicate that the prepared Ag/CuS/CC coupled DBD has great potential for safe disinfection of pathogenic bacteria in water through integrated processes.

Omiganan-Based Synthetic Antimicrobial Peptides for the Healthcare of Infectious Endophthalmitis.

Bacterial endophthalmitis is a severe infection of the aqueous or vitreous humor of the eye that can lead to permanent vision loss. Due to the rapid emergence of antibiotic resistance and dose-limiting toxicities, the standard treatment of bacterial endophthalmitis via the intravitreal injection of broad-spectrum antibiotics remains inadequate. Membrane active cationic antimicrobial peptides (AMPs) have emerged as a promising class of effective and broad-spectrum antimicrobial agents with potential to overcome antibiotic resistance. In this work, we investigate, for the first time, the use of omiganan (IK-12), a 12-amino acid indolicidin derivative for the treatment of bacterial endophthalmitis. Additionally, IK-12 was used as a template to perform amino acid rearrangements, without altering the length or type of amino acids, to yield a series of new derivative AMPs with varying extents of secondary structure formation under membrane mimicking conditions. IK-12 and its derivatives demonstrated strong and broad-spectrum antibacterial activities against a panel of clinically isolated Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus commonly implicated in bacterial endophthalmitis. Interestingly, two of the new IK-12 derivatives, IP-12 and WP-12, showed lower geometric mean minimum inhibitory concentration and higher 50% hemolysis concentration values, which effectively translated into 2- to 3.4-fold higher bacterial selectivity than the parent IK-12. Furthermore, the intravitreal injection of IK-12, IP-12, and WP-12 in a rabbit model of MRSA-induced endophthalmitis led to considerably improved clinical presentation and reduced recruitment of inflammatory cells. In all, these results demonstrate the potential of IK-12 and its derivatives, IP-12 and WP-12, as promising candidates for the treatment of bacterial endophthalmitis.

Correlation analysis between phytochemical composition and biological activities of Artemisiascoparia

As a homologous plant of medicine and food, Artemisia scoparia has rich nutritional value and medicinal components. The main contents are to analyze the phytochemical composition and various biological activities of A. scoparia, and to explore the Pearson correlation between the contents of each phytochemical composition and biological activities. The ethanol extract (EA) and its fractions (n-hexane extract (NHE), ethyl acetate extract (EAC), n-butanol extract (NBA), and water extract (HO)) of A. scoparia were rich in polyphenols, polysaccharides, terpenoids, coumarins, flavonoids and showed potential for antibacterial, antioxidant, hypoglycemic, lipid-lowering, and anti-inflammatory activities. EAC contains the highest amount of coumarins and flavonoids, shows strong antibacterial, antioxidant, hypoglycemic, lipid-lowering and anti-inflammatory (COX-2) activities. In addition, the inhibition rate of NHE on LOX was higher, and Pearson correlation reveled a strong association between phytochemical composition and biological activities: Coumarins had antimicrobial properties, flavonoids had antioxidant and hypoglycemic effects, and flavonoids and terpenoids had anti-inflammatory effects. There was a significant negative correlation between coumarins and MBC of S. aureus (r = 0.84, p < 0.001) and C. albicans (r = 0.84, p < 0.001). Flavonoids (r = 0.86, p < 0.001) showed a significant negative correlation with α-glucosidase scavenging ability. Terpenoids also showed a significantly negative correlation with LOX scavenging ability (r = 0.70, p < 0.001). A comprehensive understanding of both physiological functionalities and potential applications related to the bioactive elements present in extracts from A. scoparia could potentially provide valuable scientific insights to guide its medical or health-related utilization.

Bimetallic FeCo metal–organic framework based cascade reaction system: Enhanced peroxidase activity for antibacterial performance

Metal-organic frameworks (MOFs), as a peroxidase (POD), can catalyze the conversion of H2O2 to reactive oxygen species (ROS) for antibacterial application. To achieve strong antibacterial activity, it is necessary to improve the enzyme-like activity of MOFs. In this study, FexCoMOF was synthesized by incorporating Co(II) to improve the electron transfer of Fe(III)/Fe(II), which enhanced its redox capacity as a nanozyme and further promoted the generation of hydroxyl radical (⋅OH), exhibiting higher POD activity. Doping with different amounts of Co(II) altered the particle size, specific surface area, and surface defects of FexCoMOF, thus exhibiting differential enzyme-like activities. Additionally, a glucose-responsive enzyme cascade reaction system based on Fe4CoMOF/glucose oxidase (GOx) was established. In the presence of glucose, the in situ-generated substrate H2O2 was in contact with the catalytic site and the generated gluconic acid enabled Fe4CoMOF to maintain maximum enzyme activity under physiological pH conditions, avoiding damage caused by the use of exogenous high concentrations of H2O2. In the in vitro antibacterial experiment, the minimum inhibitory concentration (MIC) of Fe4CoMOF/GOx was 10 μg mL−1 for Escherichia coli (E. coli) and 5 μg mL−1 for Staphylococcus aureus (S. aureus) (∼108 CFU mL−1). The increase in enzyme activity resulted in a considerable reduction in the dose of the antibacterial agent, which was conducive to improving bio-safety. The in vivo experiment in mice demonstrated that the glucose-responsive Fe4CoMOF-based cascade reaction system had excellent antibacterial properties and remarkably promoted wound healing. The antibacterial agent based on bimetallic MOF developed in this work provides a new idea for cascade catalytic antibacterial therapy and will have remarkable application prospects in biomaterials and nanomedicine.

Therapeutic Potential of Insect Defensin DLP4 Against Staphylococcus hyicus-Infected Piglet Exudative Epidermitis

Background/Objectives: The emergence of resistance to Staphylococcus hyicus (S. hyicus), the major cause of exudative epidermatitis (EE) in piglets, has led to the need for new antimicrobial agents. The study aimed to evaluate the potential efficacy of the insect defensin DLP4 against EE in piglets caused by clinically isolated S. hyicus ACCC 61734. Methods and Results: DLP4 showed strong antibacterial activity against S. hyicus ACCC 61734 (minimum inhibitory concentration, MIC: 0.92 μM, median effect concentration, EC50: 3.158 μM). DLP4 could effectively inhibit the formation of S. hyicus early biofilm with an inhibition rate of 95.10–98.34% and eradicate mature biofilm with a clearance rate of 82.09–86.41%, which was significantly superior to that of ceftriaxone sodium (CRO). Meanwhile, DLP4 could efficiently inhibit bacteria in early and mature biofilm, killing up to 95.3% of bacteria in early biofilm and 87.2–90.3% of bacteria in mature biofilm. The results showed that DLP4 could be effective in alleviating the clinical symptoms of EE by down-regulating the nuclear factor κB (NF-κB) signaling pathway, balancing cytokines, inhibiting bacterial proliferation, and reducing organ tissue damage. Conclusions: This study firstly demonstrated the potential efficacy of DLP4 against EE caused by S. hyicus ACCC 61734 infection in piglets, which may be used as an alternative to antibiotics in treating EE.

Broad-spectrum antimicrobial activities of a food fermentate of Aspergillus oryzae.

The development of NP, a potent broad-spectrum antimicrobial, is a significant breakthrough in the ongoing challenge against microbial foodborne illnesses and the growing threat of antibiotic resistance. This food-grade culture broth of Aspergillus oryzae demonstrates exceptional broad-spectrum efficacy against a variety of harmful bacteria and fungi, including drug-resistant strains such as methicillin-resistant Staphylococcus aureus and prevalent food spoilage molds. NP exhibits strong bactericidal activity against various foodborne and ESKAPE pathogens, and strong antifungal activity against Penicillium species, Aspergillus fumigatus, and Candida albicans. The potent bactericidal and antifungal properties of NP are a result of its ability to disrupt microbial cell membranes leading to increased permeability. Furthermore, the genome-wide impact of NP on fungal gene expression and metabolic pathways underscores its comprehensive antimicrobial action, leading to transcriptomic and metabolic changes associated with cell death in A. fumigatus.