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Antibacterial Properties (antibacterial + property)
Selected AbstractsChemical, Mechanical, and Antibacterial Properties of Silver Nanocluster,Silica Composite Coatings Obtained by Sputtering,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Monica Ferraris Abstract Silver nanocluster,silica matrix composite coatings have been deposited by radio frequency (RF) co-sputtering on silica substrates. Field emission scanning electron microscopy and X-ray diffraction spectra of the as deposited and heated samples (150,600,°C) revealed the presence of metal silver nanoclusters, their size depending on the heating treatment. The antibacterial activity of the as deposited and heated samples has been measured in accordance to National Committee for Clinical Laboratory Standards, and it has been demonstrated on samples heated up to 450,°C in contact mode and for samples heated at 600,°C in a liquid environment. Their antibacterial activity was still present after gamma ray and ethylene oxide gas (EtO) sterilization of the samples. Silver leaching tests on the as deposited and heated samples has been measured by graphite furnace atomic absorption spectrometer, revealing an amount ranging from 0.1 to 0.9,µg mm,2, over 28 days. Tape resistance (ASTM D3359-97) and scratch resistance tests have been done on each sample revealing a good adhesion of the coatings on silica. [source] Antibacterial Properties of an Iron-based Hemostatic Agent In Vitro and in a Rat Wound ModelACADEMIC EMERGENCY MEDICINE, Issue 7 2009David O. Bracho Abstract Objectives:, Topical hemostatic agents are currently employed on the battlefield for control of major hemorrhage and have potential for use in civilian settings. Some of these compounds may also be antibacterial. Given the behavior of these compounds, the purpose of this study was to assess the potential antibacterial properties of an iron oxyacid,based topical hemostatic agent against three problematic species of wound-contaminating microorganisms: Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and methicillin-resistant Staphylococcus epidermidis. Methods:, Bacteria were treated in vitro with the test powder for 30 minutes and then assessed for viability. Long-term (8-hour) inhibition of bacterial growth was also examined. In vivo, a rat full-thickness 1-cm2 skin wound was studied. Wounds were contaminated, treated, and then quantitatively cultured 24 hours later. Results:, The lethal dose for 99% of the organisms (LD99) for the compound against each organism ranged from 0.89 (±0.28) to 4.77 (±0.66) mg/mL (p < 0.05). The compound produced sustained inhibition over 8 hours at both 1 and 5 mg/mL (p < 0.05 for each), for P. aeruginosa, S. epidermidis, and S. aureus. In vivo, activity was noted against only P. aeruginosa, with the largest magnitude reduction being on the order of 3-log colony-forming units (CFU; p < 0.01). Conclusions:, The iron-based agent studied possesses significant in vitro and lesser in vivo antibacterial effects. Further optimization of the delivery, dosing, and evaluation of this agent in a larger animal model with more humanlike skin structures may reveal important wound effects beyond control of bleeding. [source] Synthesis of Novel Isoxazolidine Derivatives and Their Antifungal and Antibacterial Properties.CHEMINFORM, Issue 39 2003Kodagahally R. Ravi Kumar Abstract For Abstract see ChemInform Abstract in Full Text. [source] Syntheses and Antibacterial Properties of iso -Platencin, Cl- iso -Platencin and Cl-Platencin: Identification of a New Lead StructureCHEMISTRY - A EUROPEAN JOURNAL, Issue 31 2010Konrad Tiefenbacher Dr. Abstract Platencin is a novel antibiotic which is active against multiresistant pathogens. We describe efficient syntheses of three platencin analogues of varying activities which allow further conclusions about the pharmacophoric part of the molecule. The unnatural antibiotic iso -platencin, which is about as active as natural platencin, but much more selective, was identified as a new lead structure. [source] Vectorization of Harungana madagascariensis Lam. ex Poir. (Hypericaceae) ethanolic leaf extract by using PLG-nanoparticles: antibacterial activity assessmentDRUG DEVELOPMENT RESEARCH, Issue 1 2005B. Moulari Abstract This study was undertaken to compare the in vitro and ex vivo antibacterial activity of an ethanolic Harungana madagascariensis leaf extract (HLE) incorporated into poly (D,L -lactide-co,glycolide) nanoparticles (HLE -PLG-NP). Two concentrations of HLE (500 and 1,000,µg/mL) for the in vitro study and one concentration (500 µg/mL) for the ex vivo study were compared using two gram-positive bacterial strains (Micrococcus luteus and Staphylococcus epidermidis), and one gram-negative bacterial strain (Moraxella sp.). The ex vivo antibacterial activity was evaluated on S. epidermidis CIP 55109 (SE) using an artificial contamination method. SE was inoculated for 12 h onto human skin fragment surfaces treated for 5,min either with HLE loaded, unloaded PLG-NP, or HLE solution. In vitro, the two preparations inhibited completely the growth of all bacterial strains at 1,000,µg/mL. However, the HLE -PLG-NP had a significant antibacterial activity against SE (18.4±1.8,0.4±0.2 CFU/mL, P<0.05), and a marked antibacterial effect against M. luteus (ML) and Moraxella sp. (Msp) compared to HLE solution at 500 µg/mL. Ex vivo, HLE -PLG-NP at 500,µg/mL reduced viable bacteria (6.3,4.8 log10), compared to the HLE solution (6.3,5.5 log10) after 4 h artificial contamination (P<0.05). A thin layer chromatography study of both HLE solution and HLE -PLG-NP showed that among the seven components found on the chromatogram of the HLE solution, only two were present on the nanoparticles, one including a flavonoid heteroside fraction responsible for the antibacterial properties. The incorporation of the HLE into a colloidal carrier improved antibacterial performance. Drug Dev. Res. 65:26,33, 2005. © 2005 Wiley-Liss, Inc. [source] Enzymes in the acquired enamel pellicleEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2005Christian Hannig The acquired pellicle is a biofilm, free of bacteria, covering oral hard and soft tissues. It is composed of mucins, glycoproteins and proteins, among which are several enzymes. This review summarizes the present state of research on enzymes and their functions in the dental pellicle. Theoretically, all enzymes present in the oral cavity could be incorporated into the pellicle, but apparently enzymes are adsorbed selectively onto dental surfaces. There is clear evidence that enzymes are structural elements of the pellicle. Thereby they exhibit antibacterial properties but also facilitate bacterial colonization of dental hard tissues. Moreover, the immobilized enzymes are involved in modification and in homeostasis of the salivary pellicle. It has been demonstrated that amylase, lysozyme, carbonic anhydrases, glucosyltransferases and fructosyltransferase are immobilized in an active conformation in the pellicle layer formed in vivo. Other enzymes, such as peroxidase or transglutaminase, have been investigated in experimental pellicles. Despite the depicted impact of enzymes on the formation and function of pellicle, broader knowledge on their properties in the in vivo -formed pellicle is required. This might be beneficial in the development of new preventive and diagnostic strategies. [source] Genetically Engineered Phage Fibers and Coatings for Antibacterial ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Joan Y. Mao Abstract Multifunctionality can be imparted to protein-based fibers and coatings via either synthetic or biological approaches. Here, potent antimicrobial functionality of genetically engineered, phage-based fibers and fiber coatings, processed at room temperature, is demonstrated. Facile genetic engineering of the M13 virus (bacteriophage) genome leverages the well-known antibacterial properties of silver ions to kill bacteria. Predominant expression of negatively charged glutamic acid (E3) peptides on the pVIII major coat proteins of M13 bacteriophage enables solution-based, electrostatic binding of silver ions and subsequent reduction to metallic silver along the virus length. Antibacterial fibers of micrometer-scale diameters are constructed from such an E3-modified phage via wet-spinning and glutaraldehyde-crosslinking of the E3-modified viruses. Silverization of the free-standing fibers is confirmed via energy dispersive spectroscopy and inductively coupled plasma atomic emission spectroscopy, showing ,0.61,µg cm,1 of silver on E3,Ag fibers. This degree of silverization is threefold greater than that attainable for the unmodified M13,Ag fibers. Conferred bactericidal functionality is determined via live,dead staining and a modified disk-diffusion (Kirby,Bauer) measure of zone of inhibition (ZoI) against Staphylococcus epidermidis and Escherichia coli bacterial strains. Live,dead staining and ZoI distance measurements indicate increased bactericidal activity in the genetically engineered, silverized phage fibers. Coating of Kevlar fibers with silverized E3 phage exhibits antibacterial effects as well, with relatively smaller ZoIs attributable to the lower degree of silver loading attainable in these coatings. Such antimicrobial functionality is amenable to rapid incorporation within fiber-based textiles to reduce risks of infection, biofilm formation, or odor-based detection, with the potential to exploit the additional electronic and thermal conductivity of fully silverized phage fibers and coatings. [source] Three New ent -Trachylobane Diterpenoids from Co-cultures of the Calli of Trewia nudiflora and Fusarium sp.HELVETICA CHIMICA ACTA, Issue 12 2009Abstract Five diterpenoids, including three new ent -trachylobane diterpenoids, i.e., (3,)-3-hydroxy- ent -trachylobane-17,19-dioic acid 19-methyl ester (1), ent -trachylobane-17,19-dioic acid 19-methyl ester (2), ent -trachylobane-17,19-dioic acid (3), and two known atisane-type ones, i.e., (16,)-16,17-dihydroxy- ent -atisan-19-oic acid methyl ester (4), and 17-hydroxy- ent -atisan-19-oic acid methyl ester (5), were isolated from the co-culture extract of the calli of Trewia nudiflora and its endophytic fungus Fusarium sp. WXE. Their structures were elucidated by spectroscopic analyses, including 1D- and 2D-NMR experiments, and HR-Q-TOF mass spectrometry. The antitumor and antibacterial properties of the new compounds were evaluated. [source] Synthesis, characterization, and antimicrobial properties of novel quaternary amine methacrylate copolymersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2008Supriya Punyani Abstract A novel amine methacrylate monomer trimethylolpropane trimethacrylate,piperazine,ethyleneglycol dimethacrylate (TMPTMA-PPZ-EGDMA) was synthesized by amination of trimethylolpropane trimethacrylate (TMPTMA) with excess of piperazine (PPZ) followed by reaction with ethyleneglycol dimethacrylate (EGDMA). Copolymerization of TMPTMA-PPZ-EGDMA with 2-hydroxyethyl methacrylate (HEMA) was carried out by free radical polymerization using ammonium persulfate (APS) and N,N,N,,N,-tetramethyl ethylenediamine (TEMED) as a redox initiator. The copolymers obtained were then quaternized with 1-iodooctane. The monomers were characterized by FTIR and 1H NMR spectral studies. The molecular weights and polydispersity values of the monomers were determined with gel permeation chromatography. Quaternized copolymers containing more than 20% amine methacrylate monomer showed microporosity in the range of 9.9,10.4 ,m. The antibacterial activity of the quaternized copolymers against Escherichia coli and Staphylococcus aureus was studied using UV,vis spectrophotometer and scanning electron microscopy. Quaternized copolymers showed broad-spectrum contact-killing antibacterial properties without releasing any active agent as checked by iodide selective ion meter. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Chlorhexidine release and antibacterial properties of chlorhexidine-incorporated polymethyl methacrylate-based resin cementJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010N. Hiraishi Abstract This study evaluated chlorhexidine release from experimental, chlorhexidine-incorporated polymethyl methacrylate (PMMA)-based resin cements prepared from Super-Bond C&B (Sun Medical) and examined the antimicrobial activity against Streptococcus mutans and Enterococcus faecalis. Chlorhexidine diacetate was added into PMMA polymer to obtain chlorhexidine concentration of 0.0, 1.0, 2.0, 3.0, and 4.0 wt %. Chlorhexidine-incorporated, cured resin disks were immersed in distilled water at 37°C for 5 weeks, and the chlorhexidine release was analyzed by high-performance liquid chromatography. The antibacterial effect of freshly mixed resin cements was examined using the agar diffusion test. For the direct contact test, the wells (n = 6) of microtiter plates were coated with cements. The coated wells were aged up to 3 weeks prior to the placement of bacterial suspensions directly on cured cements. The 3.0 and 4.0% chlorhexidine-incorporated cement exhibited chlorhexidine release for 5 weeks; however, more than 98% of chlorhexidine was retained in resin matrix. No release was detected from the 1.0 and 2.0% incorporated cement at 1 week and 2 weeks, respectively. The agar diffusion test failed to detect antibacterial effects against Enterococcus faecalis, whereas the direct contact test revealed the antibacterial effect of 3.0 and 4.0% incorporated cements against each microbe for 2 weeks. The 3.0 and 4.0% chlorhexidine-incorporated resin cement possessed prolonged chlorhexidine release and antibacterial properties for 2 weeks. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010 [source] Cefazolin embedded biodegradable polypeptide nanofilms promising for infection prevention: A preliminary study on cell responsesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2010Hongshuai Li Abstract Implant-associated infection is a serious complication in orthopedic surgery, and endowing implant surfaces with antibacterial properties could be one of the most promising approaches for preventing such infection. In this study, we developed cefazolin loaded biodegradable polypeptide multilayer nanofilms on orthopedic implants. We found that the amount of cefazolin released could be tuned. A high local concentration of cefazolin was achieved within the first a few hours and therefore may inhibit bacterial colonization in the critical postimplantation period. The developed cefazolin loaded nanofilms showed their in vitro efficacy against Staphylococcus aureus; the more antibiotics loaded, the longer the nanocoated implant had antibacterial properties. More interestingly, antibiotic-loaded polypeptide multilayer nanofilms also improved osteoblast bioactivity including cell viability and proliferation. These findings suggested that biodegradable polypeptide multilayer nanofilms as antibiotic carriers at the implant/tissue interface are compatible with human cells such as osteoblasts and bactericidal to bacteria such as S. aureus. These characteristics could be promising for preventing implant-associated infection and potentially improving bone healing. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:992,999, 2010 [source] Synthesis of metal/polymer colloidal composites by the tailored deposition of silver onto porous polymer microspheresJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2004Jin-Woong Kim Abstract A new colloidal silver system is presented in which a fine colloidal silver is in situ deposited onto functionalized porous poly(ethylene glycol dimethacrylate) [poly(EGDMA)] microspheres. The effectiveness of the silver deposition has been investigated through an examination of the surface characteristics of poly(EGDMA) microspheres. The result reported in this study demonstrate that the control of the surface area and surface functionality (in this study, a hydroxyl group) of poly(EGDMA) microspheres is an important factor that practically determines the degree of deposition of colloidal silver. X-ray analysis has shown that silver nanoparticles are dispersed evenly on inner and outer surfaces and have a face center cubic phase. Preservation testing has shown that silver-containing poly(EGDMA) microspheres have powerful antibacterial properties and, therefore, have significant potential as new preservatives. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2551,2557, 2004 [source] Chemical composition and antibacterial activities of lupin seeds extractsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 5 2003Eleonora Lampart-Szczapa Abstract Determination of influence of lupin natural phenolic compounds on antibacterial properties of its seeds was carried out. Raw material were seeds of Lupinus albus, L. luteus, and L. angustifolius. The methods included the determination of the content of proteins, total phenolic compounds, free phenolic acids, and tannins as well as antibacterial properties with ethanol extracts. The content of total phenolic compounds was smaller in testas than in cotyledons and the highest levels are observed in bitter cultivars of Lupinus albus cv. Bac andL. angustifolius cv. Mirela. Lupin tannins mainly occurred in cotyledons of the white lupin, predominantly in the bitter cultivar Bac. Free phenolic acids were mainly found in testas. Only extracts from the testas displayed antibacterial properties, which excludes the possibility of alkaloid influence on the results. The results suggest that inhibition of test bacteria growth depended mainly upon the content of the total phenolic compounds. [source] Pantoea ananatis: an unconventional plant pathogenMOLECULAR PLANT PATHOLOGY, Issue 3 2009TERESA A. COUTINHO SUMMARY Pantoea ananatis causes disease symptoms in a wide range of economically important agricultural crops and forest tree species worldwide. It is regarded as an emerging pathogen based on the increasing number of reports of diseases occurring on previously unrecorded hosts in different parts of the world. Its unconventional nature lies in the fact that, unlike the majority of plant pathogenic microbes, P. ananatis is capable of infecting humans and occurs in diverse ecological niches, such as part of a bacterial community contaminating aviation jet fuel tanks and contributing to growth promotion in potato and pepper. Taxonomy: Bacteria; Gammaproteobacteria; family Enterobacteriaceae; genus Pantoea. Microbiological properties: Gram-negative; facultatively anaerobic; most strains are motile and produce a yellow pigment in culture; indole positive. Biology:Pantoea ananatis is a common epiphyte; it also occurs endophytically in hosts where it has been reported to cause disease symptoms and in hosts where no such symptoms have been described. Some strains are ice-nucleating, a feature which has been used as a biological control mechanism against some insect pests of agricultural crops and by the food industry. Disease symptoms:Pantoea ananatis infects both monocotyledonous and dicotyledonous plants. The symptoms are diverse depending on the host infected, and include leaf blotches and spots, die-back, and stalk, fruit and bulb rot. Biological control agent:Pantoea ananatis has both antifungal and antibacterial properties. These characteristics have the potential of being exploited by biological control specialists. [source] Action of a silk fabric treated with AEGISTM in children with atopic dermatitis: A 3-month trialPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4 2007D. Y. Koller Irritation of the skin of patients with atopic dermatitis by contact with rough fibres of synthetic or woollen clothes is well known. Therefore, it has been recommended that patients should wear cotton clothes. However, cotton also consists of rough fibres able to irritate the skin, whereas silk is characterized by smooth fibres without irritating potential. The aim of our study was to evaluate the clinical effect of Dermasilk®, a special silk fabric (sericin-free silk treated with AEGIS AEM5772/5 which has antibacterial properties) , in children with atopic dermatitis. A total of 22 children with mild-to-moderate atopic dermatitis were recruited for a study period of 3 months. All of them received three different tube-fabrics , Dermasilk, sericin-free silk fabric without AEGIS AEM 5772/5 and cotton, covering the cubital region. Patients were advised to wear the Dermasilk fabric all day long during the whole study period on one arm, whereas the sericin-free AEGIS-free silk tube had to be used during the first 2 wk only on the other arm followed by the use of the cotton tube for the rest of the study period. Evaluation of the local SCORAD score was carried out at the beginning of the study, after 2, 4, 8 and 12 wk. A significant reduction of the local SCORAD index of the Dermasilk covered arm was observed after 4, 8 and 12 wk in comparison with the cotton-covered arm score [median (quartile 1,quartile 3)] 6.5 (5,8) vs. 8 (7,9), p < 0.002; 6 (5.25,7.75) vs. 8 (7,9), p < 0.0001; and 6 (5,6) vs. 8 (7.25,10), p < 0.0001. The use of Dermasilk has a significant beneficial effect in atopic dermatitis because of the non-irritating properties of silk as well as the antibacterial capacity of AEGIS AEM 5772/5. [source] Antibacterial effect of silver nanoparticles deposited on corona-treated polyester and polyamide fabricsPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 12 2008Maja Radeti Abstract The possibility of using a corona treatment (electrical discharge at atmospheric pressure) for fiber surface activation, which can facilitate the loading of silver nanoparticles (NPs) from colloids onto the polyester (PES) and polyamide (PA) fabrics and thus improve their antibacterial properties, was studied. Bactericidal efficiency and its laundering durability on silver-loaded fabrics for Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli were evaluated. The fiber morphology after corona treatment and subsequent loading of silver NPs was followed by SEM. Corona-treated fabrics loaded with silver NPs exhibited better antibacterial properties in comparison with untreated fabrics. In order to obtain acceptable laundering durability, it is necessary to use highly concentrated silver colloids. Copyright © 2008 John Wiley & Sons, Ltd. [source] Identification of a potent antibacterial factor isolated from bronchoalveolar lavage fluid: guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl-, a potential source of error in the analysis of antibacterial agentsRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2003Mirna Abraham-Nordling The widespread use of antibiotics in modern society has encouraged the search for new antibacterial compounds. In this laboratory investigations are being made to identify and characterise novel antibacterial peptides. With this in mind, the antibacterial properties of human bronchoalveolar lavage (BAL) fluid from sarcoidosis patients is being investigated. In this communication we report on the identification and characterisation of a highly active non-peptide antibacterial compound isolated from BAL fluid. The structure of this active compound was elucidated by high-resolution accurate mass and tandem mass spectrometry to be guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl-. This compound does not appear to be endogenous, and its presence in BAL fluid extracts presents a potential source of error in analysis of antibacterial agents. The biological effects of guanidine, N -[3-[(aminoiminomethyl)amino]propyl]- N -dodecyl- have not previously been described in the literature. Copyright © 2002 John Wiley & Sons, Ltd. [source] Synthesis and antibacterial properties of peptidyl derivatives and cyclopeptides structurally based upon the inhibitory centre of human cystatin C: Dissociation of antiproteolytic and antibacterial effectsAPMIS, Issue 7-8 2000FRANCISZEK Kasprzykowski Cysteine protease-inhibiting proteins of the cystatin superfamily can inhibit the replication of certain viruses and bacteria. The inhibitory centre of human cystatin C, the most widely distributed human cystatin, comprises three peptide segments. The present work describes the synthesis and antibacterial activity of 27 new peptidyl derivatives or cyclopeptides based upon the aminoterminal segment Arg8 -Leu9 -Val10 -Gly11. Fourteen of the new compounds displayed antibacterial activity against from 1 up to 9 of 17 clinically important bacterial species tested. Antiproteolytic activity of a compound was usually not required for its antibacterial capacity. Peptidyl diazomethanes generally had a very narrow antibacterial spectrum, inhibiting only Streptococcus pyogenes, whereas cyclopeptides and peptidyl derivatives of the general structure X-Arg-Leu-NH-CH(iPr)-CH2 -NH-Y had a much wider spectrum. The most potent of these substances displayed approximately equal minimal inhibitory and bactericidal concentrations of about 20 ,g/ml for both Staphylococcus aureus and S. pyogenes and were devoid of antiproteolytic activity. Several of the new substances could protect mice against lethal intraperitoneal challenge with S. pyogenes. Though their target remains to be disclosed, the group of substances here reported might be promising for the development of antibacterial drugs and the discovery of novel principles of action. [source] Antibacterial Properties of an Iron-based Hemostatic Agent In Vitro and in a Rat Wound ModelACADEMIC EMERGENCY MEDICINE, Issue 7 2009David O. Bracho Abstract Objectives:, Topical hemostatic agents are currently employed on the battlefield for control of major hemorrhage and have potential for use in civilian settings. Some of these compounds may also be antibacterial. Given the behavior of these compounds, the purpose of this study was to assess the potential antibacterial properties of an iron oxyacid,based topical hemostatic agent against three problematic species of wound-contaminating microorganisms: Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and methicillin-resistant Staphylococcus epidermidis. Methods:, Bacteria were treated in vitro with the test powder for 30 minutes and then assessed for viability. Long-term (8-hour) inhibition of bacterial growth was also examined. In vivo, a rat full-thickness 1-cm2 skin wound was studied. Wounds were contaminated, treated, and then quantitatively cultured 24 hours later. Results:, The lethal dose for 99% of the organisms (LD99) for the compound against each organism ranged from 0.89 (±0.28) to 4.77 (±0.66) mg/mL (p < 0.05). The compound produced sustained inhibition over 8 hours at both 1 and 5 mg/mL (p < 0.05 for each), for P. aeruginosa, S. epidermidis, and S. aureus. In vivo, activity was noted against only P. aeruginosa, with the largest magnitude reduction being on the order of 3-log colony-forming units (CFU; p < 0.01). Conclusions:, The iron-based agent studied possesses significant in vitro and lesser in vivo antibacterial effects. Further optimization of the delivery, dosing, and evaluation of this agent in a larger animal model with more humanlike skin structures may reveal important wound effects beyond control of bleeding. [source] Ruthenium(II) complexes incorporating tridentate Schiff base ligands: synthesis, spectroscopic, redox, catalytic and biological propertiesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2010N. Sathya Abstract A series of new diamagnetic ruthenium(II) complexes of the type [RuCl(CO)(B)(L)] (where B = PPh3, AsPh3 or Py; L = monobasic tridentate Schiff base ligands derived from o -aminophenol or o -aminothiophenol with ethylacetoacetate or ethylbenzoylacetate) have been synthesized and these complexes were characterized by physico-chemical and spectroscopic methods. Cyclic voltammograms of all the complexes show quasi-reversible oxidation in the range 0.24,1.05 V and the quasi-reversible reduction in the range , 0.14 to , 0.51 V. The observed redox potentials show little variation with respect to the replacement of triphenyl phosphine/arsine by pyridine. The complexes were tested as catalysts in the oxidation of primary and secondary alcohols using molecular oxygen at room temperature and also in CC coupling reactions. Further, the antibacterial properties of the free ligands and their metal complexes were evaluated against certain bacteria such as Escherichia coli and Staphylococcus aureus. Copyright © 2010 John Wiley & Sons, Ltd. [source] Design, synthesis, characterization and antibacterial properties of copper(II) complexes with chromone-derived compoundsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 1 2010Zahid H. Chohan Abstract A new series of six chromone-derived compounds and their Cu(II) complexes was synthesized and characterized by their physical, spectral and analytical data The elemental analysis data of the complexes agree well with the proposed composition of the compounds, which were found to be dimeric in nature with two hydrazine molecules bridging the two copper atoms through coordination. The ligands and their Cu(II) complexes were screened for their in-vitro antibacterial activity against four Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri) and two Gram-positive (Bacillus subtilis, Staphylococcus aureus) bacterial strains by the agar-well diffusion method. The ligands were found to exhibit either no or low to moderate activities against one or more of the bacterial species, whereas all the metal complexes exhibited moderate to high activities against different bacterial species. The ligands which were inactive before complexation turned active and less active ones became more active upon coordination with copper ions. Overall, the complexes 7,12 showed comparatively much higher activities than the ligands. Copyright © 2009 John Wiley & Sons, Ltd. [source] Synthesis and characterization of several cephalothin derivatives modified with germanium-containing moieties,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2005Yoshito Takeuchi Abstract A cepham, cephalothin (4), was modified with germanium-containing moieties. Their structures were confirmed chiefly based on electrospray ionization mass spectrometry and NMR spectroscopy and their antibacterial properties were tested. None of these exhibited activity strong enough to be used as a medicine. Copyright © 2005 John Wiley & Sons, Ltd. [source] Inhibitory properties and X-ray crystallographic study of the binding of AR-101, AR-102 and iclaprim in ternary complexes with NADPH and dihydrofolate reductase from Staphylococcus aureusACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2009Christian Oefner Iclaprim is a novel dihydrofolate reductase (DHFR) inhibitor belonging to the 2,4-diaminopyrimidine class of antibiotics, of which trimethoprim (TMP) is the most well known representative. Iclaprim exhibits potent bactericidal activity against major Gram-positive pathogens, notably methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) phenotypes, including TMP-resistant strains. The inhibition properties of racemic iclaprim and of the two enantiomers, termed AR-101 and AR-102, towards S. aureus wild-type DHFR and TMP-resistant F98Y mutant DHFR were determined and compared. Similar to TMP, AR-101, AR-102 and iclaprim are all competitive inhibitors with respect to the substrate dihydrofolate. Iclaprim, AR-101 and AR-102 demonstrated little or no difference in activity towards these enzymes and were significantly more potent than TMP. The crystal structures of S. aureus DHFR and F98Y mutant DHFR were determined as ternary complexes with NADPH and either AR-101, AR-102 or iclaprim. The binding modes of the inhibitors were analysed and compared. The X-ray crystallographic data explain the binding modes of all molecules well and can be used to rationalize the equipotent affinity of AR-101, AR-102 and iclaprim, which is also reflected in their antibacterial properties. [source] Mutation of bacterium Vibrio gazogenes for selective preparation of colorantsBIOTECHNOLOGY PROGRESS, Issue 2 2010Farzaneh Alihosseini Abstract A novel marine bacterium strain effectively produced prodiginine type pigments. These colorants could dye wool, silk and synthetic fabrics such as polyester and polyacrylic and also show antibacterial properties against Escherichia coli and Staphylococcus aureus bacteria on the dyed products. Methyl nitrosoguanidine was used as a mutation agent to increase the genetic diversity and the production yield of the bacteria of the family of Vibrio gazogenes. The analysis of the mutated samples showed that two new main colorants as well as three previously found ones were produced. Liquid chromatography electro spray ionization mass spectrometry (LC-ESI-MS) and nuclear magnetic resonance (NMR) spectroscopic techniques were used to elucidate the structures of the newly produced colorants. Mass measurements revealed that the colorants C1, C2, C3, C4 have molecular masses of 321, 323, 351, and 295 Da. One unstable colorant C5 with molecular mass of 309 Da was detected as well. The mutated bacteria strains increased the yield of pigment production by about 81% and produced prodigiosin in 97% purity. The antibiotic activities of pure colorants are discussed as well. Based on their bio-activity and excellent dyeing capabilities, these colorants could be employed in cosmetic and textile industries. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] A case report and critical appraisal of the literature on the use of DermaSilk® in children with atopic dermatitisCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 8 2009C. Vlachou Summary Atopic dermatitis (AD) is easily aggravated by detergents, synthetic and woollen clothing, and bacterial colonization. Cotton clothing is often recommended for children with AD, but cotton can contain rough fibres that may act as skin irritants. In contrast, silk is characterized by smooth fibres with minimal potential for irritation. We report a sericin-free silk (DermaSilk®), which is treated with AEGIS AEM5772/5, a product that has antibacterial properties, and evaluate its use in the treatment of AD. [source] Preparation of composited Nano-TiO2 and its application on antimicrobial and self-cleaning coatingsPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 5 2010Rong-Min Wang Abstract Composite nano-TiO2 with doping Fe3+ and Ag was prepared, and further modified by 3-methacryloxypropyltrimethoxysilane. They were characterized by Zetasizer Nano ZS Particle and Zeta Potential Analyzer, X-ray diffraction, UV,Vis spectrophotometer, FT,IR spectra, and transmission electron microscopy. The modified composite nano-TiO2 was applied to prepare multifunctional fluorocarbon coatings (FCC). Antibacterial activity of multifunctional FCC containing modified composite nano-TiO2 was investigated. Its photocatalytic antibacterial activity reached 92%. The influence of doping ingredients, amount of composite nano-TiO2, different light houses, or surface modification was discussed. The surface of FCC cannot be easily smirched by oiliness, dust or water because of hydrophobic fluorosilicone emulsion. It would be an available modern interior building coating for its remarkable photocatalytic antibacterial property as well as self-cleaning function. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||