Efficient Antibacterial Agents Research Articles

In-vitro Inhibition of Biofilm Formation by Pseudomonas aeruginosa isolated from Chicken

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen which is characterized by its ability to form biofilm, on biotic and abiotic surfaces, makes it particularly resistant to host's immune defenses and current antibiotic therapies. In present study, ten strains were isolated from 100 diseased chicken with percentage of 10%. The antimicrobial susceptibility for the 10 isolates was conducted using disc diffusion method. The most of isolates were resistant to Ampicillin (90%). While, Doxycyclin and Penicillin exhibited resistance with percentage of 70¬ % for each. The isolates were genotypically studied for the presence of virulence genes (pslA, toxA and fliC). The pslA, toxA genes were detected in all (100%) of isolates, while fliC gene was detected in 50% of isolates using conventional PCR technique. The ability of isolates to form in vitro biofilm was detected by tube method followed by investigating the effect of each acetic and citric acid on biofilm formation. All of P. aeruginosa isoalets were able to form biofilm while, the biofilm inhibition percentage was evaluated to be 80% for P. aeruginosa at weak acids concentration of 2%. The current study described the role of each acetic and citric acid as an efficient antibiofilm and antibacterial agents against multidrug resistant P. aeruginosa

Highly efficient disinfection based on multiple enzyme-like activities of Cu3P nanoparticles: A catalytic approach to impede antibiotic resistance

Cu3P nanoparticles (NPs) were proposed as an efficient antibacterial agent for impeding bacterial resistance. Both sensitive and resistant strains of E. coli and S. aureus (3 × 106 CFU mL−1), and the microbial populations from a fishery water were completely inactivated by Cu3P NPs (≤ 1.5 µg mL−1) within 30 min with no regrowth. The antibacterial mechanism of Cu3P NPs relied on their own multiple enzyme-like activities, to elucidate, the action of ROS produced by their oxidase- and peroxidase- like activities was facilitated by their inherent activities for glutathione depletion and the lipid peroxidation. Comparing with that traditional antibiotics induced bacterial resistance (6 out of 7) within 3 passages, Cu3P NPs kept their initially inactivated efficiency, demonstrating that they can delay the onset of bacterial resistance. Furthermore, the Cu3P NPs shown no obviously toxic effect on aquatic organisms and a negligible side-effect toward mammalian tissues. This strategy is insightful for struggle with resistant bacteria.

Application of thiabendazole/bentonites hybrids as efficient antibacterial agent against Escherichia coli and Staphylococcus aureus

Clay minerals are commonly used in agriculture, light industry, cosmetics, pharmaceuticals and other fields because it has adsorption and cation exchange properties. In this work, cetyltrimethylammonium bromide (CTAB) as a modifier and thiabendazole (TBZ) as intercalation agent to prepare composite, and their potential use as antibacterial agent was evaluated. Thiabendazole is a kind of antiparasitic drug which began to be used abroad in the early 60’s. But soon after, it was discovered that it had a strong anti-fungal effect on many molds that affect vegetables, fruits, nuts and other crops. At present, it has been widely used in prevention and control abroad. Unmodified bentonite, modified bentonite and intercalated bentonite were characterized by x ray diffraction (XRD), Fourier transform infrared (FTIR), Energy dispersive x-ray spectroscopy (EDS) and Scanning electronic microscopy (SEM), and the antimicrobial properties of the compounds was investigated by Minimum inhibitory concentrations (MIC), Minimum bactericidal concentration (MBC) and Kirby-Bauer disc agar diffusion method. Among the three compounds, the ratio of modified bentonite to thiabenazole was 5:1 showed the highest antibacterial activity against Escherichia coli and Staphylococcus aureus. In the final, there are some figures about the SEM of E. coli and S. aureus that can indicate antibacterial of the antibacterial agent.

Fluorescence Imaging and Photodynamic Inactivation of Bacteria Based on Cationic Cyclometalated Iridium(III) Complexes with Aggregation‐Induced Emission Properties (Adv. Healthcare Mater. 24/2021)

Aggregation-Induced Emission In article number 2100706 by Wai-Yeung Wong, Sijie Chen, and co-workers, cationic Ir(III) complexes with aggregation-induced emission properties are reported. These red phosphors can stain both Gram-positive and Gram-negative bacteria and demonstrate various photocytotoxicities against the bacteria. The results imply that phosphorescent metal complexes are potential candidates for bacterial imaging and efficient photo-based antibacterial agents.

Surfactant assisted CuO/MCM-41 nanocomposite: Ultra efficient photocatalyst for degradation of methylene blue dye and inactivation of highly drug resistant bacteria

In recent years, metal and metal oxide modified mesoporous materials have attracted great attention in science and technology due to their remarkable properties, such as mesoscopic bulky shape, large surface area, and interconnected porous structures enabling them to be one of the most exciting materials for biomedical and photocatalytic applications. In this paper, we used a hydrothermal technique to investigate new multifunctional nanostructural material i.e. CuO-MCM-41. The obtained nanocomposites were characterized using XRD, FTIR, UV, SEM, HRTEM, EDX and BET analyses. The as synthesized nanomaterials were screened for the photocatalytic degradation of methylene blue (MB) under visible light irradiation. In the presence of CuO-MCM-41 photocatalyst, 97% MB was degraded only in 30 min of irradiation. The CuO-MCM-41 is an efficient antibacterial agent with effective light inhibition activity against E. coli, S. aureus, S. typhimurium, K. pneumoniae, and B. subtilis. The production of reactive oxygen species (ROS) was also analysed. Furthermore, the nanomaterial is also an efficient DPPH stabilizing agent. The hydrothermally prepared CuO-MCM-41 nanocomposite may be a promising material for removing hazardous organic compounds and microorganisms.

Design, Synthesis, Antibacterial Activity, Antiviral Activity, and Mechanism of Myricetin Derivatives Containing a Quinazolinone Moiety.

Plant bacteria such as Xanthomonas axonopodispv. citri (Xac), Pseudomonas syringaepv. actinidiae (Psa), Xanthomonas oryzaepv. oryzae (Xoo), and tobacco mosaic virus (TMV) have created huge obstacles to the global trade of food and economic crops. However, traditional chemical agents used to control these plant diseases have gradually become disadvantageous due to long-term irregular use. Therefore, finding new and efficient antibacterial and antiviral agents is becoming imperative. In this study, a series of myricetin derivatives containing a quinazolinone moiety were designed and synthesized, and the antibacterial and antiviral activities of these compounds were evaluated. The bioassay results showed that some target compounds exhibited good antibacterial activities in vitro and antiviral activities in vivo. Among them, the median effective concentration (EC50) value of compound L18 against Xac was 16.9 μg/mL, which was better than those of the control drugs bismerthiazol (BT) (62.2 μg/mL) and thiodiazole copper (TC) (97.5 μg/mL). Scanning electron microscopy (SEM) results confirmed that compound L18 inhibited the growth of Xac by affecting the morphology of cells. Microscale thermophoresis (MST) test results indicated that the dissociation constant (Kd) value of compound L11 against TMV-CP was 0.012 μM, which was better than that of the control agent ningnanmycin (2.726 μM). This study reveals that myricetin derivatives containing a quinazolinone moiety are potential antibacterial and antiviral agents.

Possibility for double optimization of siRNA intracellular delivery efficiency and antibacterial activity: Structure screening of pH-sensitive triblock amphiphilic polycation micelles

Optimal combination of hydrophobic-hydrophilic balance, proton buffering and electrostatic interaction is the key issue for designing polycations as efficient gene vectors and antibacterial agents. Herein, we screened a series of pH-sensitive quaternary ammonium-based amphiphilic triblock copolymers, mPEG2k-P(DPAa/DMAb)-PQAc (TDDE-x), which had different pKa values and proton buffering capacities. Significantly, we found that both the highest siRNA intracellular delivery efficiency and the strongest antibacterial capacity occurred on TDDE-3 micelles with the segment structure of mPEG2k-P(DPA50/DMA56)-PQA55. The TDDE-3/siRNA complex achieved 67% silencing efficiency on H9C2 cells (N/P = 5, 50 nM siRNA), higher than the advanced commercial transfection reagents RNAiMAX (58%) and Lipo2000 (30%). Moreover, TDDE-3 micelles showed quite low MICs of 32 μg/mL and 8 μg/mL against E. coli and S. aureus, respectively. Further studies on the structure-function relationship indicated that TDDE-3 micelles could mediate robust endosome escape and siRNA cytosolic release, and strong bacterial cell membrane-destabilizing function. Undoubtedly, this work reveals the possibility for double optimization of siRNA intracellular delivery efficiency and antibacterial activity of amphiphilic polycations by reasonable structure design, which is significant for low-cost development and clinical translation of efficient multifunctional polycations.

N-doped three-dimensional graphene aerogel with a high loading of Ag particles as an efficient catalyst and antibacterial agent

In this work, N-doped three-dimensional graphene aerogel with different weight of Ag particles (N-GA/Ag) was successfully prepared by a one-step solvothermal method. The characterization proved the successful doping of N and the weaken bonds between N atoms and Ag particles. The scanning electron microscopy images showed that the sizes of Ag particles were 10–50 nm at optimal load. Serving as water treated materials for 4-nitrophenol (4-NP), the N-GA/6Ag composite exhibited that its high catalytic reduction capacity in the presence of NaBH4 reached at 98% within 4 min and the bactericidal performance for E. coli could achieved 100% inactivation rate in 24 h. This work also calculated surface atomic densities of exposed main planes of Ag particles, which were relative to the catalytic performance. The catalytic activity of the {111} crystal planes was lower than that of {100} planes in Ag particles.

Effect of Titanium Nanoparticles Biosynthesized by Lactobacillus crispatus against Multi Drug Resistance Bacteria isolated from patient with Recurrent UTI

Background: The synthesis of metal nanoparticles using microorganisms has received great interest due to their optical, chemical, photoelectrical and electronic properties. The microorganisms are used as possible ―nanofactories‖ for development of clean, nontoxic and environmentally friendly methods for producing nanoparticles, the Nanoparticle are synthesized using various biosources such as bacteria, fungi, yeast, plant extract Objectives: The present study focuses on the biosynthesis of titanium nanoparticles using Iraqi Lactobacillus crispatus isolate and their inhibitory effect against multi drug resistance bacteria isolated from patient with Recurrent UTI and against their ESBL and Metallo beta lactamase. Materiales and Methods: Lactobacillus crispatuswas isolated from vagina of Iraqi healthy women then identified throughoutcultural, microscopical and biochemical test. Fifty samples of urine were collected from women suffering from recurrent UTI who had certain clinical symptoms; these samples were collected from Rizgary Teaching Hospital and Baghdad Teaching Hospital from August to September, 2013 with ages ranging from 18-60 years. The urine specimens were inoculated on both blood and MacConkeys agar plates. The isolates were identified throughout cultural, microscopical, biochemical test and Vitek 2 system. Isolates were tested against 14 antibiotics by using Kirby-Bauer disc diffusion and detection of Extend spectrum β- lactamases by double disc diffusion synergy method and detection of Metallo-β lactamase by disc potentiating test and Samples of synthesized nanoparticles were characterized after 72 hours of incubation. The formation of metal oxide TiO2 nanoparticles was confirmed by X-ray diffraction (XRD) technique, Atomic Force Microscopy (AFM) and Scanning electron microscopic (SEM) and antibacterial activity of TiO2 nanoparticles synthesized by L. crispatus were determined on the basis of minimum inhibitory concentration (MIC) values Effect of TiO2 nanoparticles on metallo-β lactamase and evaluation of combined effect between Antibiotics and synthesized TiO2 nanoparticles. Results: Fifty samples of urine were collected from patient suffering from recurrent UTI who had certain clinical symptoms. Forty four isolates (88%) were isolated and identified from fifty samples of urine, 13 isolates (29.5%) belonged to Escherichia coli which was the most predominant and 6 isolates (13.6%) belonged to Klebsiella pneumonia, 5 isolates (11.3%) belonged to Psudomonasaeruginosa , 2 isolates (4.5%) belonged to Acinetobacterbaumannii, one isolate belonged to M.morganii, 11 isolates (25%) belonged to S.aureusand 6 isolates (13.6%) belonged to S.saprophyticusMoreover , these isolates were tested for susceptibility to (13) antibiotics and for their ability to produce extended β –lactmase and metalo β- lactmaseenzymes. All isolates were resist to Ampicillin, Amoxicillin/ clavulanicacid and Aztreonam. Inhibitory effect of synthesized TiO2 nanoparticles was studied against growth and ESBL and Metallo beta lactamase of recurrent UTI causative bacteria. Results showed the MIC of TiO2 nanoparticles was (32) mgml against E. coli, M.morganii, A.baumanii and S.aureus, and (64) mgml against K.pneumoniae, P.aeruginosa and S.saprophyticus isolates.TiO2 nanoparticles showed inhibitory effect on metalloβ lactmase produced by E.coli, M.morganiiand A.baumanii., thereduction in inhibition zone diameter of MBL positive isolates of A.baumanii(1) and E.colifrom (2o to 25) mm after treatment with TiO2 nanoparticles compared to control without treatment with TiO2 nanoparticles (25-35,20- 30) mm respectively, while inhibition zone diameters of M.morganiiand A.baumanii (2) were(15,20),(10,20) mm respectively after treatment compared to control with inhibition zone diameters (23,30), (30,38) mm. The combined effect between Antibiotics and synthesized TiO2 nanoparticles was also investigated against multi resistant recurrent UTI causative bacteria. The antibacterial activities of some antibiotics such as Ampicillin and Gentamycin have been increased in the presence of TiO2 nanoparticle (subMIC) against all isolates. Conclusions: Titanium nanoparticles has more efficient antibacterial agent and can be useful in the treatment of infectious diseases caused bybacteria, the combination of antibiotics and metal nanoparticles could increase the antibiotics‘ efficacy against resistant pathogens. In addition, nanoparticle–antibiotic conjugates lower the amount of both agents in the dosage, which reduces harmfulness and increases antimicrobial properties.

Co3O4/PANI nanocomposites as a photocatalytic, antibacterial and anticorrosive agent: Experimental and theoretical approach

The cobalt oxide (Co3O4) nanoparticles (NPs) were synthesized by the reverse micelle technique. Polyaniline (PANI) conducting polymer was produced by the chemical oxidative technique. Co3O4/PANI nanocomposites (NCs) were synthesized by in-situ technique. The Co3O4 NPs, PANI, and Co3O4/PANI NCs were characterized by FT-IR, UV visible, TEM, and X-ray diffraction methods. The average particle size of Co3O4, PANI, and NCs was determined by XRD and TEM techniques and was found to be almost the same. Experimental findings were supported by the theoretical (DFT) study. Antibacterial, anticorrosive, and photocatalytic properties of Co3O4/PANI NCs were investigated. Co3O4/PANI NCs show 82.23% corrosion inhibition efficiency at 1000 mg/ml concentration. The antibacterial activity of Co3O4/PANI NCs was compared with six standard antibiotics for both gram-positive and gram-negative bacteria. The photocatalytic property of Co3O4/PANI NCs was tested against methylene orange dye. Co3O4/PANI NCs (100 mg/ml) degrade 81.25% of methyl orange dye after 3 h of UV light illumination. Zone of Inhibition shown by Co3O4/PANI NCs (1000 mg/ml concentration) for S. epidermis and E. coli bacterial strain was comparable to six standard antibiotics. The synthesized Co3O4/PANI NCs were proved to be a very efficient corrosion inhibitor , antibacterial, and photo-degrading agent.

Synthesis and Characterization of Antibacterial Carbopol/ZnO Hybrid Nanoparticles Gel

This study recommends Carbopol/zinc oxide (ZnO) hybrid nanoparticles gel as an efficient antibacterial agent against different bacterial species. To this end, ZnO nanoparticles were synthesized using chemical precipitation derived from a zinc acetate solution with ammonium hydroxide as its precipitating agent under the effect of ultrasonic radiation. The synthesized ZnO nanoparticles were stabilized simultaneously in a freshly prepared Carbopol gel at a pH of 7. The chemical composition, phase identification, particle size and shape, surface charge, pore size distribution, and the BET surface area of the ZnO nanoparticles, as well as the Carbopol/ZnO hybrid Nanoparticles gel, were by XRD, SEM, TEM, AFM, DLS, Zeta potential and BET instruments. The results revealed that the synthesized ZnO nanoparticles were well-dispersed in the Carbopol gel network, and have a wurtzite-crystalline phase of spherical shape. Moreover, the Carbopol/ZnO hybrid nanoparticles gel exhibited a particle size distribution between ~9 and ~93 nm, and a surface area of 54.26 m2/g. The synthesized Carbopol/ZnO hybrid nanoparticles gel underwent an antibacterial sensitivity test against gram-negative K. pneumonia (ATCC 13883), Bacillus subtilis (ATCC 6633), and gram-positive Staphylococcus aureus (ATCC 6538) bacterial strains, and were compared with ampicillin as a reference antibiotic agent. The obtained results demonstrated that the synthesized Carbopol/ZnO hybrid nanoparticles gel exhibited a compatible bioactivity against the different strains of bacteria.

Cobalt phosphide nanowires as efficient near-infrared light-driven antibacterial agents with high stability and cytocompatibility

Rapid emergence of antibiotic-resistant bacteria has brought huge threat to global healthcare systems. Alternative strategies are urgently needed to fight against these superbugs. In this study, we synthesized a series of cobalt phosphide nanoarchitectures and characterized their physicochemical properties as well as their antibacterial activities. We found that all nanomaterials showed an impressive photothermal property as indicated by their strong near-infrared (NIR) absorption capacity. In particular, 1D-CoP nanowires exhibited the optimal photothermal efficiency due to their higher aspect ratio. Under NIR light illumination, the temperature of the 1D-CoP nanowires suspension was increased by 45.4 °C within 20 min. In contrast, the temperatures of 2D-CoP nanoplates and 3D-CoP nanocubes were increased by 25.5 °C and 26.9 °C, respectively. The growth of planktonic bacteria can be effectively inhibited by 99% within 30 min under NIR irradiation with the presence of 1D-CoP nanowires in suspension. In comparison, up to 60% of the bacteria could be killed when treated with 2D-CoP nanoplates and 3D-CoP nanocubes. Moreover, all nanomaterials displayed high cytocompatibility. This work emphasizes that the anisotropy plays an important role in governing the photothermal properties of NIR-driven materials. Furthermore, the application of CoP nanowires is a promising strategy to treat antibiotic-resistant bacteria.

Synthesis of composite derived from carbon nanoparticles and digallate stabilized silver nanoparticles for their bactericidal efficacy

Current study reports synthesis, characterisation and antibacterial efficacy of nanocomposites derived from carbon nanoparticles (CNP) and silver nanoparticles (AgNPs). The reaction was performed at ambient temperature and digallate (dimer of gallic acid) was used as an active stabilizing and reducing agent. The CNP-AgNP nanocomposite (CNP-AgNC) was characterised by UV–vis, HR-TEM, SEM, Zeta potential and DLS. These composites were examined for their antibacterial efficacy using the strains Staphylococcus aureus, Bacillus subtilis, Streptomyces griseus and Escherichia coli. Our study reveals that this proposed nanocomposite is an efficient antibacterial agent.

Dual-role of graphene/bacterial cellulose/magnetite nanocomposites as highly effective antibacterial agent and visible-light-driven photocatalyst

Magnetite (Fe3O4) NPs as well as bacterial cellulose (BC)/Fe3O4 and graphene (Gr)/BC/Fe3O4 nanocomposites (NCs) were synthesized by a hydrothermal method and characterized by spectroscopic, crystallographic and microscopic characterization techniques. Their antibacterial activities were subsequently tested against ESBL-producing Escherichia coli and Proteus mirabilis. Gr/BC/Fe3O4 NCs showed 100% antibacterial activity, whereas BC/Fe3O4 NCs and Fe3O4 NPs showed values of 97.3% and 94.6% as well as 96.6% and 94.3%, respectively, for E. coli and P. mirabilis at a concentration of 100 μg/mL. The minimum inhibitory concentration of Gr/BC/Fe3O4 NCs against E. coli and P. mirabilis were found to be 60 and 70 μg/mL, respectively. The photocatalytic degradation efficiencies of Fe3O4 NPs as well as BC/Fe3O4 and Gr/BC/Fe3O4 NCs were quantified by UV–visible spectrophotometry against organic dye molecules including bromothymol blue (BTB), rhodamine B (Rh-B) and methylene blue (MB) upon exposure to visible light. Gr/BC/Fe3O4 NCs showed the fastest (40 min) and 100% degradation efficiency against BTB, whereas 100% of Rh-B and MB were degraded within 50 min and 70 min, respectively. Our results demonstrate the multifunctionality of Gr/BC/Fe3O4 NCs for use as highly efficient antibacterial agent and photocatalyst.

Silver Nanoparticles and Their Antibacterial Applications

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.

Epsilon-polylysine based magnetic nanospheres as an efficient and recyclable antibacterial agent for Alicyclobacillus acidoterrestris

In this work, polyacrylic acid modified ferroferric oxide (Fe3O4-PAA) was synthesized via a one-step hydrothermal method. The magnetic nanospheres modified with carboxyl groups were combined with epsilon-polylysine (EPL) via an EDC/NHS coupling reaction to obtain Fe3O4-PAA-EPL nanospheres. Fe3O4-PAA-EPL was employed as an antibacterial agent against Alicyclobacillus acidoterrestris and characterized by XRD, FTIR, XPS, VSM, SEM and TEM techniques. Experimental results showed the minimum inhibition concentration (MIC) of Fe3O4-PAA-EPL against A. acidoterrestris was 1.25 mg mL−1. Furthermore, A. acidoterrestris treated with Fe3O4-PAA-EPL nanospheres obviously lysed. Morphological analysis of bacteria supported by SEM indicated that the cell membrane of A. acidoterrestris was damaged, revealing that Fe3O4-PAA-EPL is an effective antibacterial agent. Additionally, the nanospheres with excellent magnetism can be simply separated from a reaction system via an external magnet. The construction of magnetic nanospheres with satisfactory antibacterial activity provides an effective and new method to control A. acidoterrestris.

Design, Synthesis, Antibacterial Evaluation and Molecular Docking Studies of Some Newer Baenzothiazole Containing Aryl and Alkaryl Hydrazides.

The alarming rise of bacterial resistance is occurring worldwide and endangering the efficacy of antibiotics. Therefore, development of new and efficient antibacterial agents remains paramount. In the present work, we designed and synthesized a series of N'-(1,3-benzothiazol-2-yl)-substituted aryl/aralkyl hydrazides C1-C27 and evaluated them in vitro for their antibacterial activity. Among all tested compounds, C10, C15, and C24 showed potent activity against Staphylococcus aureus ATCC 43300 (MRSA). Minimum bactericidal concentration studies of synthesized compounds are performed against selected bacterial strains. Time kill kinetics showed that the compounds C10 and C15 possess bactericidal activity against MRSA ATCC 43300, while compound C24 possess bactericidal activity against S. aureus NCIM 5022. In the extra-precision docking, compounds C1-C27 exhibited interactions mainly with the N-terminal and central domains of S. aureus GyrB catalytic pocket. Binding free energy (ΔGbind ) of compounds C1-C27/3U2K complexes were computed by MM-GBSA approach. Free energy components indicated Coulomb energy term as favorable for binding, while van der Waals and electrostatic solvation energy terms strongly disfavored the binding. ADMET properties of synthesized compounds C1-C27 are also computed.

Synergistic antimicrobial activity of silver nanoparticles combined with streptomycin sulfate against gram-negative and gram-positive bacteria

Synergistic antibacterial effect of green synthesized silver nanoparticles combined with antibiotic on Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) was conducted, respectively. Well diffusion, growth curve, anti-biofilm, and colony formation were applied to evaluate its antimicrobial activity. Significant synergistic effect was found when silver nanoparticles were combined with streptomycin sulfate at ratios of 8:2 and 9:1 for E. coli, while 5:5 and 8:2 for S. aureus. It suggested that silver nanoparticles were proved to be an efficient antibacterial agent, and the challenge like drug resistance would also be able to resolve under the condition of silver nanoparticles combined with antibiotics.

Antibacterial Vitamin K3 Carnosine Peptide-Laden Silk Fibroin Electrospun Fibers for Improvement of Skin Wound Healing in Diabetic Rats.

The utilization of a multifunctional bioactive molecule functionalized electrospun dressing in tissue repair and regenerative function is a prominent therapeutic strategy for preparing efficient biomaterials to promote chronic wound healing. Designing robust and highly efficient antibacterial agents in resistance against microbes and bacterial infections is a key challenge for accelerating diabetic wound healing until today. In this study, we developed a vitamin K3 carnosine peptide (VKC)-laden silk fibroin electrospun scaffold (SF-VKC) for diabetic wound healing. The structural confirmation of synthesized VKC was characterized by 1H NMR, 13C NMR, electrospray ionization mass spectrometry (ESI-MS), and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy analysis, and the cell viability of VKC was evaluated by the CCK-8 assay in HFF1 and NIH 3T3 cells. VKC shows excellent cell viability on both cell lines, and the VKC and SF-VKC electrospun mats exhibited excellent antibacterial activity against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. Prepared SF and SF-VKC fibrous mats were well characterized, and the SF-VKC nanofiber mat presented good biodegradability, adhesiveness, unique mechanical property, expedient water uptake property, sustained drug release, and excellent biocompatibility for chronic wound healing. The in vitro tissue engineering study depicted excellent cell migration and cell-cell interaction in the NIH 3T3 cells over the VKC-impregnated silk fibroin (SF-VKC) mat. A higher population of cell migration was observed in cells' denuded area (scratched region) compared to the native SF fibrous mat. Interestingly, our results demonstrated that the prepared VKC-impregnated SF mat had potentially promoted the STZ-induced diabetic wound healing in a shorter period than the pure SF mat. Thus, obtained in vitro and in vivo outcomes suggest that the VKC-laden SF electrospun fibrous mat could be a better and inexpensive fibrous antibacterial biomaterial to elicit earlier re-epithelialization and efficient matrix remodeling for accelerating chronic infected wound reconstruction in skin diabetic wound healing applications.

Cover Image, Volume 138, Issue 33

Yanqin Shi and colleagues prepared one kind of highly efficient compound antibacterial agents by grafting green natural organic antibacterial agents to (3-aminopropyl) triethoxysilane modified zinc oxide sheets. The polypropylene composites with the compound antibacterial agents have excellent antibacterial effect on both the Escherichia coli and Staphylococcus aureus, due to the double synergistic antibacterial effects. Meanwhile, the compound antibacterial agents have excellent migration resistance. DOI: 10.1002/app.50911