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Sample records for antibacterial nucleosides effective

  1. Antibacterial effects of glass ionomers.

    Science.gov (United States)

    DeSchepper, E J; White, R R; von der Lehr, W

    1989-04-01

    Glass ionomer cements have been shown to possess antimicrobial activity. Proposed mechanisms of action include acidity and fluoride. It was the purpose of this study to determine the antimicrobial effect of 11 glass ionomer cements, their individual powder and liquid components and one resin-bonded liner containing high fluoride ionomer glass against Streptococcus mutans #6715. The role of fluoride and pH in the antibacterial activity was also studied. Using agar diffusion assay methodology, the following results were obtained. All of the glass ionomer cements were inhibitory against S. mutans. The antibacterial cements and slurries that were tested for fluoride, released the ion in excess of reported minimum inhibitory values. The antimicrobial activity of the liquid components, that were tested for the effects of pH changes, was totally lost when the pH was adjusted to 5. The resin bonded liner was inactive against S. mutans and did not release inhibitory concentrations of fluoride. These results indicate that freshly-mixed glass ionomer cements are antimicrobial against S. mutans and that the mechanism of action is probably a function of both fluoride and pH although additional factors may be involved.

  2. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

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    Daniel Wiegmann

    2016-04-01

    Full Text Available Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY, a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field.

  3. Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

    Science.gov (United States)

    Wirth, Marius; Niro, Giuliana; Leyerer, Kristin

    2016-01-01

    Summary Muraymycins are a promising class of antimicrobial natural products. These uridine-derived nucleoside-peptide antibiotics inhibit the bacterial membrane protein translocase I (MraY), a key enzyme in the intracellular part of peptidoglycan biosynthesis. This review describes the structures of naturally occurring muraymycins, their mode of action, synthetic access to muraymycins and their analogues, some structure–activity relationship (SAR) studies and first insights into muraymycin biosynthesis. It therefore provides an overview on the current state of research, as well as an outlook on possible future developments in this field. PMID:27340469

  4. Antibacterial Effect of Human Amnion Membrane

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    Kashani, L. (MD

    2015-01-01

    Full Text Available Background and Objective: Along with antibiotics, the use of biological methods to combat bacteria is notably considered. A natural barrier such as amniotic membrane is one of the ways of dealing with bacterial infections. The aim of this study was to determine the antibacterial effect of human amniotic membrane. Materials and Methods: This descriptive study was performed in Dezyani teaching Hospital of Gorgan University of Medical Sciences, Iran. To evaluate the antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli bacteria, 20 amniotic membranes were obtained from postpartum mothers and examined by repeated dilution, diffusion and extraction techniques. Data were collected by observation method and described by mean and standard deviation. Results: The antibacterial activity was found in 15% of the samples against Staphylococcus Aureus and Pseudomonas aeruginosa, while no antibacterial activity was found against E. coli. Given the 15% positive responses, "Diffusion" and "repeated dilution" techniques were more effective in investigating the antibacterial effect of amniotic membrane. Conclusion: The results show the probability of antimicrobial effect of amniotic membrane tissue and it seems that this property can be affected by many factors.

  5. Inhibitory Effect of Bridged Nucleosides on Thermus aquaticus DNA Polymerase and Insight into the Binding Interactions.

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    Sung-Kun Kim

    Full Text Available Modified nucleosides have the potential to inhibit DNA polymerases for the treatment of viral infections and cancer. With the hope of developing potent drug candidates by the modification of the 2',4'-position of the ribose with the inclusion of a bridge, efforts were focused on the inhibition of Taq DNA polymerase using quantitative real time PCR, and the results revealed the significant inhibitory effects of 2',4'-bridged thymidine nucleoside on the polymerase. Study on the mode of inhibition revealed the competitive mechanism with which the 2',4'-bridged thymidine operates. With a Ki value of 9.7 ± 1.1 μM, the 2',4'-bridged thymidine proved to be a very promising inhibitor. Additionally, docking analysis showed that all the nucleosides including 2',4'-bridged thymidine were able to dock in the active site, indicating that the substrate analogs reflect a structural complementarity to the enzyme active site. The analysis also provided evidence that Asp610 was a key binding site for 2',4'-bridged thymidine. Molecular dynamics (MD simulations were performed to further understand the conformational variations of the binding. The root-mean-square deviation (RMSD values for the peptide backbone of the enzyme and the nitrogenous base of the inhibitor stabilized within 0.8 and 0.2 ns, respectively. Furthermore, the MD analysis indicates substantial conformational change in the ligand (inhibitor as the nitrogenous base rotated anticlockwise with respect to the sugar moiety, complemented by the formation of several new hydrogen bonds where Arg587 served as a pivot axis for binding formation. In conclusion, the active site inhibition of Taq DNA polymerase by 2',4'-bridged thymidine suggests the potential of bridged nucleosides as drug candidates.

  6. Antibacterial Effects of Silver Loaded Hydroxyapatite

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The antibacterial capability of silver loaded hydroxyapatite(HA-Ag) in both poor nutrient phosphate buffer saline solution(PBS,pH=7.4)and nutrient rich medium,which represented two kinds of typical conditions in real life,was evaluated respectively using Escherichia coli as a model.At 0.4 mg/mL in PBS solution containing an initial cell concentration of 106/mL,HA-Ag killed all the E.coli cells in the PBS solution within 4.5 h.In a nutrient rich medium containing a cell concentration of 107/mL,HA-Ag exhibited a remarkable inhibitory effect of E.coli cells.The maximum specific growth rate in the medium containing 3 mg/mL HA-Ag was only 0.292, 26% of that in a control sample which was 1.116,and the viable cell concentration in the former HA-Ag medium was just 40% of that in the control.As a safe antibacterial agent,HA-Ag powder demonstrated antibacterial efforts both in poor nutrient and in nutrient rich environment.It seems that the HA-Ag compound hold a lot of promises for practical applications.

  7. Antibacterial effect of Gracilaria verrucosa bioactive on fish pathogenic bacteria

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    Maftuch

    2016-12-01

    Full Text Available Gracilaria verrucosa seaweed is a type of seaweed commonly found in water. This study was conducted to investigate the effect of G. verrucosa on fish pathogenic bacteria to support fish farming. The method used in this research was the separation of G. verrucosa fractions using column chromatography. The active antibacterial fraction of G. verrucosa which is obtained from column chromatography indicated fractions containing antibacterial compounds. It was fraction number 3 by using an eluent 16 (ethanol: 4 (ethyl acetate. Furthermore, based on phytochemical screening, ultraviolet spectrophotometer and LC–MS analysis, antibacterial compounds contained in those fraction number 3 are Alkaloid, Flavonoid, Tannin, Phenolic compound. Based on LC–MS and UV–Vis analysis, flavonoid group, Quercetin-7-methyl-ether is a dominant group of the antibacterial compound on fraction no. 3. This fraction had moderate antibacterial activity against Aeromonas hydrophila, Pseudomonas aeruginosa, Pseudomonas putida and had weak antibacterial activity against Vibrio harveyi and Vibrio algynoliticus bacteria.

  8. Extrahepatic effects of nucleoside and nucleotide analogues in chronic hepatitis B treatment.

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    Fung, James; Seto, Wai-Kay; Lai, Ching-Lung; Yuen, Man-Fung

    2014-03-01

    Oral nucleoside/nucleotide analogues (NAs) are the mainstay of therapy for patients with chronic hepatitis B and are generally well tolerated. Despite this, the safety profile of NAs is of paramount importance since the majority of patients will require long-term treatment. All NAs can potentially affect human DNA polymerase with decrease in mitochondrial DNA, leading to manifestations of mitochondrial toxicity. As a class effect, therefore, NAs can potentially cause extrahepatic conditions, such as myopathy, nephropathy, neuropathy, and lactic acidosis. Indeed, effects on muscles, including myopathy and creatine kinase elevations, have been described with clevudine and telbivudine use. Both adefovir and tenofovir are associated with dose-dependent nephropathy, predominantly affecting the proximal renal tubules. Neuropathy appears to be rare, and most commonly reported in patients receiving combination therapy with telbivudine and interferon. Increased risk of lactic acidosis has also been described for those with impaired liver and renal function taking entecavir. Loss of bone mineral density and hypophosphatemia have been described with the use of NAs, although the overwhelming studies have been with human immunodeficiency virus-infected patients. However, not all extrahepatic effects are detrimental. Recent evidence has suggested a potential renal beneficial effect with the use of telbivudine. The effect of NAs on pregnancy appears to be minimal for all NAs, with telbivudine and tenofovir having a more favorable category B rating. Ongoing pharmacovigilance is essential to identify new and monitor existing extrahepatic effects associated with NA use.

  9. Antibacterial effect of five Zingiberaceae essential oils.

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    Norajit, Krittika; Laohakunjit, Natta; Kerdchoechuen, Orapin

    2007-08-23

    Essential oil obtained by hydrodistillation and two different solvent extractions (petroleum ether and ethanol) from five Zingiberaceae species: ginger (Zingiber officinale Roscoe.), galanga (Alpinia galanga Sw.), turmeric (Curcuma longa L.), kaempferia (Boesenbergia pandurata Holtt.) and bastard cardamom (Amomum xanthioides Wall.) was characterized. Volatile components of all extracts were analyzed by gas chromatography-mass spectrometry (GC-MS). The major components of ginger, turmeric, galangal, bastard cardamom and kaempferia were zingiberene, turmerone, methyl chavicol, and gamma-terpinene, respectively. Their antibacterial effects towards Escherichia coli, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes were tested by a disc diffusion assay. Essential oil of kaempferia and bastard cardamom obtained by hydrodistillation extraction could inhibit growth of all tested bacteria. Essential oil of ginger extracted by hydrodistillation had the highest efficiency against three positive strains of bacteria (S. aureus, B. cereus and L. monocytogenes), with a minimum concentration to inhibit B. cereus and L. monocytogenes of 6.25 mg/mL.

  10. Calculations of the Energetics of Oxidation of Aqueous Nucleosides and the Effects of Prototropic Equilibria.

    Science.gov (United States)

    Close, David M; Wardman, Peter

    2016-06-16

    Recently the calculated standard reduction potentials of the radical-cations of N-methyl substituted DNA bases have been reported that agree fairly well with the experimental results. However, there are issues reflecting the fact that the experimental results usually relate to the couple E(o)(Nuc(•),H(+)/NucH(+)), whereas the calculated results are for the E(o)(Nuc(•+)/Nuc) couple. To calculate the midpoint reduction potential at pH 7 (Em7), it is important to have accurate acid dissociation constants (pKs) for both ground-state bases and their radicals, and the effects of uncertainty in some of these values (e.g., that of the adenosine radical) must be considered. Calculations of the pKs of the radicals of the nucleic acid bases (as nucleosides) have been performed to explore the effects the various pKs have on calculating the values of Em7 and to see what improvements can be made with the accuracy of the calculations.

  11. Antibacterial effects of Solanum tuberosum peel ethanol extract in vitro

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    Amanpour Raana

    2015-04-01

    Full Text Available Introduction: Today, medicinal plants are being widely used due to being natural, available, and cheaper than synthetic drugs and having minimum side effects. Since there were reports about the antibacterial properties of Solanum tuberosum (SE, the aim of this study was to investigate the antibacterial effects of SE ethanol extract in vitro condition on Streptococcus pyogenes, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. Methods: Ethanol extract of SE peel was prepared by maceration method. Initially, antibacterial activity of ethanol extract of SE was qualitatively determined by disk diffusion test; then, the minimum inhibitory concentration and minimum bactericidal concentration were qualitatively determined by micro-dilution method. Results: SE peel extract had antibacterial properties and its effect was more pronounced on gram-positive bacteria, especially S. aureus (0.62±0.00 mg/ml. The extract had antibacterial activity on gram-negative bacteria, P. aeruginosa, too (8.33±2.88 mg/ml. Conclusion: SE peel extract has antibacterial activity and its effect on gram-positive bacteria was more pronounced than the investigated gram-negative bacteria. Therefore, it is suggested that SE peel constituent compounds be determined and to determine the exact mechanism of its antibacterial properties, and more comprehensive research be done to apply it, clinically.

  12. Antibacterial Effect of the Conducting Polyaniline

    Institute of Scientific and Technical Information of China (English)

    Nanlin SHI; Xuemei GUO; Hemin JING; Jun GONG; Chao SUN; Ke YANG

    2006-01-01

    Excellent antibacterial performance of polyaniline (Pani) against Escherichia coli and Gram-positive Staphylococcus aureus microorganisms has been demonstrated under both dark and visible light conditions. The electrostatic adherence between the Pani molecules and the bacteria may play a very important role for the antibacterial reaction of the Pani. As a result of our investigation, conducting Pani and its composites/blends are believed to be useful as a new type of antibacterial agent, self-clean as well as multifunctional material for improving the human health and living environment.

  13. BCX4430, a novel nucleoside analog, effectively treats yellow fever in a Hamster model.

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    Julander, Justin G; Bantia, Shanta; Taubenheim, Brian R; Minning, Dena M; Kotian, Pravin; Morrey, John D; Smee, Donald F; Sheridan, William P; Babu, Yarlagadda S

    2014-11-01

    No effective antiviral therapies are currently available to treat disease after infection with yellow fever virus (YFV). A Syrian golden hamster model of yellow fever (YF) was used to characterize the effect of treatment with BCX4430, a novel adenosine nucleoside analog. Significant improvement in survival was observed after treatment with BCX4430 at 4 mg/kg of body weight per day dosed intraperitoneally (i.p.) twice daily (BID). Treatment with BCX4430 at 12.5 mg/kg/day administered i.p. BID for 7 days offered complete protection from mortality and also resulted in significant improvement of other YF disease parameters, including weight loss, serum alanine aminotransferase levels (6 days postinfection [dpi]), and viremia (4 dpi). In uninfected hamsters, BCX4430 at 200 mg/kg/day administered i.p. BID for 7 days was well tolerated and did not result in mortality or weight loss, suggesting a potentially wide therapeutic index. Treatment with BCX4430 at 12 mg/kg/day i.p. remained effective when administered once daily and for only 4 days. Moreover, BCX4430 dosed at 200 mg/kg/day i.p. BID for 7 days effectively treated YF, even when treatment was delayed up to 4 days after virus challenge, corresponding with peak viral titers in the liver and serum. BCX4430 treatment did not preclude a protective antibody response, as higher neutralizing antibody (nAb) concentrations corresponded with increasing delays of treatment initiation, and greater nAb responses resulted in the protection of animals from a secondary challenge with YFV. In summary, BCX4430 is highly active in a hamster model of YF, even when treatment is initiated at the peak of viral replication.

  14. Chemical Composition and Antibacterial Effects of

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    SS Saei Dehkordi

    2009-10-01

    Full Text Available Introduction & Objective: Rosmarinus officinalis L. as a member of the Lamiaceae family and lysozyme as a natural antibacterial agent is important in food microbiology, because of its characteristics. The aim of the present study was to determine the chemical composition and anti-listerial activity of Rosmarinus officinalis essential oil (REO alone and in combination with lysozyme for enhancement of anti-listerial activity of both substances. Materials & Methods: Rosmarinus officinalis L. was purchased from a local grocery store at Shahrekord and was identified by the Institute of Medicinal Plants, ACECR. The air-dried aerial parts were subjected to hydrodistillation using a Clevenger apparatus to obtain essential oil and yielded oil was analyzed by GC/MS. Antibacterial activity (on basis of Minimum Inhibitory Concentration (MIC of REO was studied separately and in combination with unheated lysozyme (L and heat-treated lysozyme (HTL on Listeria monocytogenes at different pH (5, 6 and 7 by a micro-broth dilution assay. The collected data were analyzed by SPSS software. Results: In the current study, 98.05% of constituents of the essential oil were identified. The major components were α-pinene (14.06%, 1,8-cineole (13.62%, verbenone (11.2%, camphor (10.51%, borneol (7.3%, 3-octanone (7.02%, camphene (5.46% and linalool (5.07%. The inhibitory action of REO was stronger at lower pH especially 5 (MIC=225 μg/mL. Inhibition by L at pH 5 was 640 μg/mL but no inhibition was seen at pH 7. HTL resulted in more effective inhibition than L, especially at pH 5 and heat-treatment 80˚C (MIC: 160 μg/mL. Conclusion: Combination of L + REO and particularly HTL + REO was led to enhancement of bacterial inhibition. It was concluded that REO by the identified chemical composition was effective alone or in combination with L or HTL on Listeria monocytogenes as a food-borne pathogen.

  15. Antibacterial Effect of Five Zingiberaceae Essential Oils

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    Orapin Kerdchoechuen

    2007-08-01

    Full Text Available Essential oil obtained by hydrodistillation and two different solvent extractions (petroleum ether and ethanol from five Zingiberaceae species: ginger (Zingiber officinale Roscoe., galanga (Alpinia galanga Sw., turmeric (Curcuma longa L., kaempferia (Boesenbergia pandurata Holtt. and bastard cardamom (Amomum xanthioides Wall. was characterized. Volatile components of all extracts were analyzed by gas chromatographymass spectrometry (GC-MS. The major components of ginger, turmeric, galangal, bastard cardamom and kaempferia were zingiberene, turmerone, methyl chavicol, and γ-terpinene, respectively. Their antibacterial effects towards Escherichia coli, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes were tested by a disc diffusion assay. Essential oil of kaempferia and bastard cardamom obtained by hydrodistillation extraction could inhibit growth of all tested bacteria. Essential oil of ginger extracted by hydrodistillation had the highest efficiency against three positive strains of bacteria (S. aureus, B. cereus and L. monocytogenes, with a minimum concentration to inhibit B. cereus and L. monocytogenes of 6.25 mg/mL.

  16. Antibacterial effect of Gracilaria verrucosa bioactive on fish pathogenic bacteria

    OpenAIRE

    Maftuch,; Isma Kurniawati; Awaludin Adam; I’ah Zamzami

    2016-01-01

    Gracilaria verrucosa seaweed is a type of seaweed commonly found in water. This study was conducted to investigate the effect of G. verrucosa on fish pathogenic bacteria to support fish farming. The method used in this research was the separation of G. verrucosa fractions using column chromatography. The active antibacterial fraction of G. verrucosa which is obtained from column chromatography indicated fractions containing antibacterial compounds. It was fraction number 3 by using an eluent ...

  17. Evaluation of Antibacterial Effectiveness of Desensitizers against Oral Bacteria

    OpenAIRE

    Duran, Ismet; Sengun, Abdulkadir; Hadimli, Hasan Huseyin; Ulker, Mustafa

    2008-01-01

    Objectives Desensitizers contribute to better clinical results by reducing the rate of cervical dentin sensitivity. However, information on their antibacterial effect is limited. This study examined the antibacterial activities of a triclosan containing (Seal & Protect), a benzalconium containing desensitizer (Micro Prime), a fluoride containing prophilaxy paste (Sultan Desensitizer), two fluoride containing varnishes (Cavity Shealth and Ultra EZ), and a dentin bonding primer (All Bond). Meth...

  18. Renal transepithelial transport of nucleosides.

    Science.gov (United States)

    Nelson, J A; Vidale, E; Enigbokan, M

    1988-01-01

    Previous work from this and other laboratories has suggested that the mammalian kidney has unique mechanisms for handling purine nucleosides. For example, in humans and in mice, adenosine undergoes net renal reabsorption whereas deoxyadenosine is secreted [Kuttesch and Nelson: Cancer Chemother. Pharmacol. 8, 221 (1982)]. The relationships between these renal transport systems and classical renal organic cation and anion, carbohydrate, and cell membrane nucleoside transport carriers are not established. To investigate possible relationships between such carriers, we have tested effects of selected classical transport inhibitors on the renal clearances of adenosine, deoxyadenosine, 5'-deoxy-5-fluorouridine (5'-dFUR), and 5-fluorouracil in mice. The secretion of deoxyadenosine and 5'-dFUR, but not the reabsorption of adenosine or 5-fluorouracil, was prevented by the classical nucleoside transport inhibitors, dipyridamole and nitrobenzylthioinosine. Cimetidine, an inhibitor of the organic cation secretory system, also inhibited the secretion of 5'-dFUR, although it did not inhibit deoxyadenosine secretion in earlier studies [Nelson et al.: Biochem. Pharmacol. 32, 2323 (1983)]. The specific inhibitor of glucose renal reabsorption, phloridzin, failed to inhibit the reabsorption of adenosine or the secretion of deoxyadenosine. Failure of the nucleoside transport inhibitors and phloridzin to prevent adenosine reabsorption suggests that adenosine reabsorption may occur via a unique process. On the other hand, inhibition of the net secretion of deoxyadenosine and 5'-dFUR by dipyridamole and nitrobenzylthioinosine implies a role for the carrier that is sensitive to these compounds in the renal secretion (active transport) of these nucleosides.

  19. MINERAL PROFILE EVOLUTION OF SOME MEDICINAL PLANTS WITH ANTIBACTERIAL EFFECTS

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    Claudia Pasca

    2016-11-01

    Full Text Available Individual minerals and antibacterial activity were investigated in 5 medicinal plants (pot marigold - Calendula officinalis, burdock - Arctium lappa, celandine - Chelidonium majus, basil- Ocimum basilicum, thyme - Thymus vulgaris using Atomic Absorption Spectroscopy (AAS technique and antibiogram  method. The antibacterial susceptibility has been evaluated over 12 strains isolated from milk microflora, belonging to Staphylococcus, Vibrio, Serratia and Bacillus genera. The obtained results show the best antibacterial effect with  Arctium lappa ethanol extracts, having inhibition areas of 6.3 to 17.5 mm, with an average of 9.0 mm and the highest determined mineral being Calcium. The results obtained open the prospect of using these medicinal plants as an alternative to be used for the control and cure of some mineral deficiencies or for preventing various diseases of the animals.

  20. ANTIBACTERIAL EFFECT OF CALCIUM HYDROXIDE IN DIFFER ENT VEHICLES

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    Hari

    2012-11-01

    Full Text Available ABSTRACT: AIM: This study evaluated the antibacterial effect of ca lcium hydroxide in different vehicles in an in vitro model. MATERIAL AND METHODS: Calcium hydroxide paste prepared with two conventionally used vehicles namely, campho rated monochlophenol, distilled water and also propylene glycol. The antibacterial activity of these paste were tested against five micro- organisms that can commonly occur in the inf ected root canals. RESULTS AND CONCLUSIONS: The results of the study indicate that a paste of ca lcium hydroxide made with propylene glycol exerts significant antibacterial act ion. Hence, it can be recommended for use as an intracanal medicament in preference to a paste prepa red with a tissue toxic phenolic compound like camphorated mono chlorophenol

  1. Photodynamic antibacterial effect of graphene quantum dots.

    Science.gov (United States)

    Ristic, Biljana Z; Milenkovic, Marina M; Dakic, Ivana R; Todorovic-Markovic, Biljana M; Milosavljevic, Momir S; Budimir, Milica D; Paunovic, Verica G; Dramicanin, Miroslav D; Markovic, Zoran M; Trajkovic, Vladimir S

    2014-05-01

    Synthesis of new antibacterial agents is becoming increasingly important in light of the emerging antibiotic resistance. In the present study we report that electrochemically produced graphene quantum dots (GQD), a new class of carbon nanoparticles, generate reactive oxygen species when photoexcited (470 nm, 1 W), and kill two strains of pathogenic bacteria, methicillin-resistant Staphylococcus aureus and Escherichia coli. Bacterial killing was demonstrated by the reduction in number of bacterial colonies in a standard plate count method, the increase in propidium iodide uptake confirming the cell membrane damage, as well as by morphological defects visualized by atomic force microscopy. The induction of oxidative stress in bacteria exposed to photoexcited GQD was confirmed by staining with a redox-sensitive fluorochrome dihydrorhodamine 123. Neither GQD nor light exposure alone were able to cause oxidative stress and reduce the viability of bacteria. Importantly, mouse spleen cells were markedly less sensitive in the same experimental conditions, thus indicating a fairly selective antibacterial photodynamic action of GQD.

  2. Selective antibacterial effects of mixed ZnMgO nanoparticles

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    Vidic, Jasmina, E-mail: jasmina.vidic@jouy.inra.fr [VIM, Institut de la Recherche Agronomique (France); Stankic, Slavica, E-mail: slavica.stankic@insp.jussieu.fr; Haque, Francia [CNRS, Institut des Nanosciences de Paris, UMR 7588 (France); Ciric, Danica; Le Goffic, Ronan; Vidy, Aurore [VIM, Institut de la Recherche Agronomique (France); Jupille, Jacques [CNRS, Institut des Nanosciences de Paris, UMR 7588 (France); Delmas, Bernard [VIM, Institut de la Recherche Agronomique (France)

    2013-05-15

    Antibiotic resistance has impelled the research for new agents that can inhibit bacterial growth without showing cytotoxic effects on humans and other species. We describe the synthesis and physicochemical characterization of nanostructured ZnMgO whose antibacterial activity was compared to its pure nano-ZnO and nano-MgO counterparts. Among the three oxides, ZnO nanocrystals-with the length of tetrapod legs about 100 nm and the diameter about 10 nm-were found to be the most effective antibacterial agents since both Gram-positive (B. subtilis) and Gram-negative (E. coli) bacteria were completely eradicated at concentration of 1 mg/mL. MgO nanocubes (the mean cube size {approx}50 nm) only partially inhibited bacterial growth, whereas ZnMgO nanoparticles (sizes corresponding to pure particles) revealed high specific antibacterial activity to Gram-positive bacteria at this concentration. Transmission electron microscopy analysis showed that B. subtilis cells were damaged after contact with nano-ZnMgO, causing cell contents to leak out. Our preliminary toxicological study pointed out that nano-ZnO is toxic when applied to human HeLa cells, while nano-MgO and the mixed oxide did not induce any cell damage. Overall, our results suggested that nanostructured ZnMgO, may reconcile efficient antibacterial efficiency while being a safe new therapeutic for bacterial infections.

  3. Antibacterial Effect of Juglans Regia Bark against Oral Pathologic Bacteria

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    Faramarz Zakavi

    2013-01-01

    Full Text Available Background. In this study antimicrobial effect of ethanolic and aqueous extracts of Juglans regia bark in Iran was evaluated on four different oral bacteria, Streptococcus mutans, Streptococcus salivarius, Streptococcus sanguis, and Staphylococcus aureus. Methods. Aqueous and ethanol extracts of Juglans regia bark were prepared by using disk diffusion technique and Minimal Inhibitory Concentration (MIC methods. Tetracycline 30 μg and Erythromycin 15 μg were used as positive control and water as negative control in disk diffusion and MIC methods. Data were analyzed by ANOVA test. Results. The results showed that S. sanguis and S. mutans were the most sensitive and the most resistant bacteria against ethanolic and aqueous extracts, respectively. Ethanolic extract had significant antibacterial effect against all tested bacteria. Aqueous extract did not show antibacterial effect on S. mutans, in contrast to ethanolic extract. Aqueous extract had significantly antibacterial effect against Staphylococcus aureus, S. salivarius, and S. sanguis compared to control (P<0.0001, but it did not show effect on S. mutans when compared with Erythromycin. According to the obtained MIC values, ethanol extract of Juglans regia bark had the lowest rate. Conclusion. The results may provide the basis for using natural antimicrobial substance for oral hygiene prophylaxis purposes.

  4. Trypanosoma brucei brucei: effects of ferrous iron and heme on ecto-nucleoside triphosphate diphosphohydrolase activity.

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    Leite, Milane S; Thomaz, Rachel; Oliveira, José Henrique M; Oliveira, Pedro L; Meyer-Fernandes, José Roberto

    2009-02-01

    Trypanosoma brucei brucei is the causative agent of animal African trypanosomiasis, also called nagana. Procyclic vector form resides in the midgut of the tsetse fly, which feeds exclusively on blood. Hemoglobin digestion occurs in the midgut resulting in an intense release of free heme. In the present study we show that the magnesium-dependent ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) activity of procyclic T. brucei brucei is inhibited by ferrous iron and heme. The inhibition of E-NTPDase activity by ferrous iron, but not by heme, was prevented by pre-incubation of cells with catalase. However, antioxidants that permeate cells, such as PEG-catalase and N-acetyl-cysteine prevented the inhibition of E-NTPDase by heme. Ferrous iron was able to induce an increase in lipid peroxidation, while heme did not. Therefore, both ferrous iron and heme can inhibit E-NTPDase activity of T. brucei brucei by means of formation of reactive oxygen species, but apparently acting through distinct mechanisms.

  5. Antibacterial effect of taurolidine (2%) on established dental plaque biofilm.

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    Arweiler, Nicole Birgit; Auschill, Thorsten Mathias; Sculean, Anton

    2012-04-01

    Preliminary data have suggested that taurolidine may bear promising disinfectant properties for the therapy of bacterial infections. However, at present, the potential antibacterial effect of taurolidine on the supragingival plaque biofilm is unknown. To evaluate the antibacterial effect of taurolidine on the supragingival plaque biofilm using the vital fluorescence technique and to compare it with the effect of NaCl and chlorhexidine (CHX), 18 subjects had to refrain from all mechanical and chemical hygiene measures for 24 h. A voluminous supragingival plaque sample was taken from the buccal surfaces of the lower molars and wiped on an objective slide. The sample was then divided into three equal parts and mounted with one of the three test or control preparations (a) NaCl, (b) taurolidine 2% and (c) CHX 0.2%. After a reaction time of 2 min, the test solutions were sucked of. Subsequently, the plaque biofilm was stained with fluorescence dye and vitality of the plaque flora was evaluated under the fluorescence microscope (VF%). Plaque samples treated with NaCl showed a mean VF of 82.42 ± 6.04%. Taurolidine affected mean VF with 47.57 ± 16.60% significantly (p taurolidine). Taurolidine possesses a significant antibacterial effect on the supragingival plaque biofilm which was, however, not as pronounced as that of CHX.

  6. Effect of Hydrogen Peroxide on the Antibacterial Substantivity of Chlorhexidine

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    Shahriar Shahriari

    2010-01-01

    Full Text Available The purpose of this in vitro study was to assess the effect of hydrogen peroxide on the antibacterial substantivity of chlorhexidine (CHX. Seventy-five dentine tubes prepared from human maxillary central and lateral incisor teeth were used. After contamination with Enterococcus faecalis for 14 days, the specimens were divided into five groups as follows: CHX, H2O2, CHX + H2O2, infected dentine tubes (positive control, and sterile dentine tubes (negative control. Dentine chips were collected with round burs into tryptic soy broth, and after culturing, the number of colony-forming units (CFU was counted. The number of CFU was minimum in the first cultures in all experimental groups, and the results obtained were significantly different from each other at any time period (<.05. At the first culture, the number of CFU in the CHX + H2O2 group was lower than other two groups. At the other experimental periods, the CHX group showed the most effective antibacterial action (<.05. Hydrogen peroxide group showed the worst result at all periods. In each group, the number of CFU increased significantly by time lapse (<.05. In conclusion, H2O2 had no additive effect on the residual antibacterial activity of CHX.

  7. Effect of pressurization on antibacterial properties of Lactobacillus strains

    Science.gov (United States)

    Jankowska, Agnieszka; Grześkiewicz, Aleksandra; Wiśniewska, Krystyna; Reps, Arnold

    2010-03-01

    The objective of the study was to determine the effect of high pressures on antibacterial properties of selected strains of the Lactobacillus species. Cultures of 22 strains were subjected to high-pressure treatment at 30, 60, 90, and 300 MPa/1 min/18 °C. The susceptibility of the bacteria pressurized at 30-90 MPa was diversified and depended on the strain and not on its species affiliation. When compared with pressures of 30-90 MPa, the pressure treatment at 300 MPa caused the inhibition of the acidifying activity of the strains analyzed. In turn, the pressures applied had no impact on the quantity of hydrogen peroxide synthesized. An increase in pressure was accompanied by a diminishing antibacterial activity of the investigated Lactobacillus strains.

  8. Deposition of silver nanoparticles on titanium surface for antibacterial effect

    Directory of Open Access Journals (Sweden)

    Liao Juan

    2010-04-01

    Full Text Available Liao Juan1, Zhu Zhimin3, Mo Anchun1,2, Li Lei1, Zhang Jingchao11State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041, PR China; 2Department of Dental Implant, West China Stomatology Hospital, Sichuan University, Chengdu 610041, PR China; 3Department of Prosthodontics, West China Stomatology Hospital, Sichuan University, Chengdu 610041, PR ChinaAbstract: Microbial colonization on implanted devices and biofilm formation is a recurrent complication in implant surgery and may result in loss of implants. The aim of this study was to deposit silver nanoparticles on a titanium surface to obtain antibacterial properties. In the present study, we prepared a silver nanoparticle-modified titanium (Ti-nAg surface using silanization method. The morphology and chemical components of the Ti-nAg surface were characterized by scanning electron microscopy (SEM equipped with energy-dispersive spectroscopy (EDS. Two species of bacteria, Staphylococcus aureus and Escherichia coli, were utilized to test the antibacterial effect of the Ti-nAg treated surface. The SEM examination revealed that a small quantity of silver nanoparticles was sparsely deposited on the titanium surface. The diameter of these nanoparticles ranged from ten to several hundred nm. EDS analyses revealed that there was 4.26% of Ag present on the surface. After a 24-hour incubation, 94% of Staphylococcus aureus and over 95% of Escherichia coli had been killed on the Ti-nAg surface, and the SEM examination of anti-adhesive efficacy test showed that there were less bacteria attached to Ti-nAg surface than to a control surface of untreated Titanium. These data suggest that silver nanoparticle-modified titanium is a promising material with an antibacterial property that may be used as an implantable biomaterial.Keywords: nano-silver, titanium, antibacterial activity, silanization method

  9. Phytochemical analysis, antioxidant and antibacterial effects of sea buckthorn berries.

    Science.gov (United States)

    Chaman, Saadia; Syed, Nawazish-I-Husain; Danish, Zeeshan; Khan, Farrakh Zia

    2011-07-01

    Sea buckthorn berries are therapeutically used as folk medicine for a variety of diseases, however, the scientific evidence is hardly available to support their role. This study explored their chemical constituents and their role as antioxidant and antibacterial agents. Three common solvents such as petroleum ether (40° - 60°C), chloroform and methanol were successively used for the extraction of active principles from sea buckthorn berries. Five major fractions (F1-F5) were isolated from the active methanol extract by column and thin layer chromatography. An attempt was made to identify the chemical nature of pooled fractions by available spectral means. Antioxidant potential of methanol extract and its fractions was measured by DPPH, formation of phosphomolybdenum complex and TBA methods. The hole-plate diffussion method was used to find out the antibacterial activity. A very brief structure-activity relationship of the potent antioxidant and antimicrobial compounds is discussed. Methanolic extract and its fractions contain numerous phenolic compounds such as flavonoids, which may be responsible for antioxidant and antibacterial effects.

  10. Effect of an Antibacterial Monomer on the Antibacterial Activity of a Pit-and-Fissure Sealant

    Science.gov (United States)

    Dong, Yan; Zhang, Ling; Sun, Xiang; Liu, Zhengya; Guo, Huihui; Huang, Li; Chen, Jihua

    2016-01-01

    Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB)-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt) was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea); a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™), a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM) in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05), whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane integrity of S

  11. The effect of non-alcoholic fatty liver disease on virologic response in patients with hepatitis B e antigen-positive chronic hepatitis B treated with nucleoside analogues

    Institute of Scientific and Technical Information of China (English)

    陈梅琴

    2014-01-01

    Objective To investigate the effect of non-alcoholic fatty liver disease(NAFLD)on virologic response in chronic hepatitis B patients treated with nucleoside analogues.Methods Three hundred and thirty-two treatment-naive patients with hepatitis B e antigen(HBeAg)-positive chronic hepatitis B(CHB)who visited clinic or hospitalized in the First Affiliated Hospital of Wenzhou Medical College from January 2007 to December 2009

  12. Study on antibacterial effect of medlar and hawthorn compound extract in vitro.

    Science.gov (United States)

    Niu, Yang; Nan, Yi; Yuan, Ling; Wang, Rong

    2013-01-01

    This paper evaluated the antibacterial effect of medlar and hawthorn compound extract in vitro. Water extract method and ethanol extraction method was adopted to prepare the compound extracts, and disc diffusion method and improved test tube doubling dilution method were used to conduct the antibacterial test on the two common pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumonia, in vitro. The results showed that medlar and hawthorn compound extract was moderately sensitive to Staphylococcus aureus, while its inhibiting effect on Klebsiella pneumoniae was particularly significant, moreover, the antibacterial effect of ethanol extract was better than water extract. Medlar and hawthorn compounds had good antibacterial effect on the two pathogenic bacteria.

  13. The halo-substituent effect on Pseudomonas cepacia lipase-mediated regioselective acylation of nucleosides: A comparative investigation.

    Science.gov (United States)

    Wang, Zhao-Yu; Bi, Yan-Hong; Yang, Rong-Ling; Duan, Zhang-Qun; Nie, Ling-Hong; Li, Xiang-Qian; Zong, Min-Hua; Wu, Jie

    2015-10-20

    In this work, comparative experiments were explored to investigate the substrate specificity of Pseudomonas cepacia lipase in regioselective acylation of nucleosides carrying various substituents (such as the H, F, Cl, Br, I) at 2'- and 5-positions. Experimental data indicated that the catalytic performance of the enzyme depended very much on the halo-substituents in nucleosides. The increased bulk of 2'-substituents in ribose moiety of the nucleoside might contribute to the improved 3'-regioselectivity (90-98%, nucleosides a-d) in enzymatic decanoylation, while the enhancement of regioselectivity (93-99%) in 3'-O-acylated nucleosides e-h could be attributable to the increasing hydrophobicity of the halogen atoms at 5-positions. With regard to the chain-length selectivity, P. cepacia lipase displayed the highest 3'-regioselectivity toward the longer chain (C14) as compared to shorter (C6 and C10) ones. The position, orientation and property of the substituent, specific structure of the lipase's active site, and acyl structure could account for the diverse results.

  14. Deodorant effects of a sage extract stick: Antibacterial activity and sensory evaluation of axillary deodorancy

    OpenAIRE

    Mohammad Ali Shahtalebi; Mustafa Ghanadian; Ali Farzan; Niloufar Shiri; Dariush Shokri; Syed Ali Fatemi

    2013-01-01

    Background: Deodorant products prevent the growth and activity of the degrading apocrine gland bacteria living in the armpit. Common antibacterial agents in the market like triclosan and aluminum salts, in spite of their suitable antibacterial effects, increase the risk of Alzheimer′s disease, breast and prostate cancers or induce contact dermatitis. Therefore, plant extracts possessing antibacterial effects are of interest. The aim of the present study was to verify the in vitro antimicrobia...

  15. Antibacterial effect of phosphates and polyphosphates with different chain length.

    Science.gov (United States)

    Lorencová, Eva; Vltavská, Pavlína; Budinský, Pavel; Koutný, Marek

    2012-01-01

    The aim of this study was to monitor the antibacterial effect of seven phosphate salts on selected strains of Gram-negative and Gram-positive bacteria, which could be considered responsible for food-borne diseases (Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Micrococcus luteus, Staphylococcus aureus, Citrobacter freundii, Escherichia coli, Proteus mirabilis, Salmonella enterica ser. Enteritidis and Pseudomonas aeruginosa). For these purposes, phosphates differing in chain length were used. The tested concentrations were in the range of 0.1-2.0% (wt v(-1)) applied at the model conditions. In the majority of cases the visible inhibitory effect on the growth of observed microorganisms could be seen. Due to the chemical structure of salts and their dissociation both the pH values of cultivation broth and similarly the growth characteristics of bacterial strains were affected. The inhibition of above mentioned bacteria was apparently supported by this dissociation. Phosphates obviously made the development of most Gram-positive bacteria impossible. Especially Micrococcus luteus was extremely sensitive to the presence of these substances. On the other hand, Gram-negative bacteria seemed to be resistant to the phosphate incidence. The exemption clause from the tested salts was represented by a high alkaline trisodium phosphate. It should be pointed out that generally the most significant antibacterial effects were shown by polyphosphates HEXA68 and HEXA70, trisodium phosphate undecahydrate, tetrasodium pyrophosphate and finally trisodium phosphate. By comparing the inhibitory effects of various phosphate salts can be concluded that the antibacterial activity was not determined only by the condensation degree but there was also proved the dependence on pH values.

  16. In Vitro Antibacterial Effect of Effective Microorganisms( EM) on Aeromonas hydrophila

    Institute of Scientific and Technical Information of China (English)

    Zhu; Zhixiu; He; Houjun; Zhang; Wenbo; Wu; Xiangdong; Wan; Gen; Deng; Shunzhou; Liu; Songlin

    2014-01-01

    In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.

  17. Antibacterial activity of silver-killed bacteria: the "zombies" effect

    Science.gov (United States)

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-04-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.

  18. Synergistic Antibacterial Effect between Silibinin and Antibiotics in Oral Bacteria

    Directory of Open Access Journals (Sweden)

    Young-Soo Lee

    2012-01-01

    Full Text Available Silibinin is a composition of the silymarin group as a hepatoprotective agent, and it exhibits various biological activities, including antibacterial activity. In this study, the antibacterial activities of silibinin were investigated in combination with two antimicrobial agents against oral bacteria. Silibinin was determined with MIC and MBC values ranging from 0.1 to 3.2 and 0.2 to 6.4 μg/mL, ampicillin from 0.125 to 64 and 0.5 to 64 μg/mL, gentamicin from 2 to 256 and 4 to 512 μg/mL, respectively. The ranges of MIC50 and MIC90 were 0.025–0.8 μg/mL and 0.1–3.2 μg/mL, respectively. The antibacterial activities of silibinin against oral bacteria were assessed using the checkerboard and time-kill methods to evaluate the synergistic effects of treatment with ampicillin or gentamicin. The results were evaluated showing that the combination effects of silibinin with antibiotics were synergistic (FIC index <0.5 against all tested oral bacteria. Furthermore, a time-kill study showed that the growth of the tested bacteria was completely attenuated after 2–6 h of treatment with the MBC of silibinin, regardless of whether it was administered alone or with ampicillin or gentamicin. These results suggest that silibinin combined with other antibiotics may be microbiologically beneficial and not antagonistic.

  19. Effect of antibacterial dental adhesive on multispecies biofilms formation.

    Science.gov (United States)

    Zhang, K; Wang, S; Zhou, X; Xu, H H K; Weir, M D; Ge, Y; Li, M; Wang, S; Li, Y; Xu, X; Zheng, L; Cheng, L

    2015-04-01

    Antibacterial adhesives have favorable prospects to inhibit biofilms and secondary caries. The objectives of this study were to investigate the antibacterial effect of dental adhesives containing dimethylaminododecyl methacrylate (DMADDM) on different bacteria in controlled multispecies biofilms and its regulating effect on development of biofilm for the first time. Antibacterial material was synthesized, and Streptococcus mutans, Streptococcus gordonii, and Streptococcus sanguinis were chosen to form multispecies biofilms. Lactic acid assay and pH measurement were conducted to study the acid production of controlled multispecies biofilms. Anthrone method and exopolysaccharide (EPS):bacteria volume ratio measured by confocal laser scanning microscopy were performed to determine the EPS production of biofilms. The colony-forming unit counts, scanning electron microscope imaging, and dead:live volume ratio decided by confocal laser scanning microscopy were used to study the biomass change of controlled multispecies biofilms. The TaqMan real-time polymerase chain reaction and fluorescent in situ hybridization imaging were used to study the proportion change in multispecies biofilms of different groups. The results showed that DMADDM-containing adhesive groups slowed the pH drop and decreased the lactic acid production noticeably, especially lactic acid production in the 5% DMADDM group, which decreased 10- to 30-fold compared with control group (P biofilms compared with control group (P biofilm had a more healthy development tendency after the regulation of DMADDM. In conclusion, the adhesives containing DMADDM had remarkable antimicrobial properties to serve as "bioactive" adhesive materials and revealed its potential value for antibiofilm and anticaries clinical applications.

  20. Antibacterial effect of bismuth subsalicylate nanoparticles synthesized by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Castañeda, Mariela [Instituto Nacional de Investigaciones Nucleares (Mexico); Vega-Jiménez, Alejandro L., E-mail: argelia.almaguer@mac.com; Almaguer-Flores, Argelia [Universidad Nacional Autónoma de México, Facultad de Odontología, DEPeI, I (Mexico); Camps, Enrique; Pérez, Mario [Instituto Nacional de Investigaciones Nucleares (Mexico); Silva-Bermudez, Phaedra [Instituto Nacional de Rehabilitación, Unidad de Ingeniería de Tejidos, Terapia Celular y Medicina Regenerativa (Mexico); Berea, Edgardo [FarmaQuimia SA de CV. (Mexico); Rodil, Sandra E. [Universidad Nacional Autónoma de México, Instituto de Investigaciones en Materiales (Mexico)

    2015-11-15

    The antimicrobial properties of bismuth subsalicylate (BSS) nanoparticles against four opportunistic pathogens; E. coli, P. aeruginosa, S. aureus, and S. epidermidis were determined. BSS nanoparticles were synthesized by pulse laser ablation of a solid target in distilled water under different conditions. The nanoparticles were characterized using high-resolution transmission electron microscopy and absorption spectra and small angle X-ray scattering. The analysis shows that the colloids maintained the BSS structure and presented average particle size between 20 and 60 nm, while the concentration ranges from 95 to 195 mg/L. The antibacterial effect was reported as the inhibition ratio of the bacterial growth after 24 h and the cell viability was measured using the XTT assay. The results showed that the inhibition ratio of E. coli and S. epidermidis was dependant on the NPs size and/or concentration, meanwhile P. aeruginosa and S. aureus were more sensitive to the BSS nanoparticles independently of both the size and the concentration. In general, the BSS colloids with average particle size of 20 nm were the most effective, attaining inhibition ratios >80 %, similar or larger than those obtained with the antibiotic used as control. The results suggest that the BSS colloids could be used as effective antibacterial agents with potential applications in the medical area.

  1. Determination of in-vitro antibacterial effects of breast milk

    Directory of Open Access Journals (Sweden)

    C N Akujobi

    2009-01-01

    Full Text Available Background:Breast milk undisputedly is the ideal baby food. It provides a lot of protective functions for the baby as well complete nutrition. It contains fat, proteins carbohydrates, vitamins and minerals. There have been various claims that it cures ailments. The study was therefore designed to substantiate those claims. Objective: To determine the in vitro antibacterial effects of breast milk Methodology:Expressed breast milk of nursing mothers who were not on antibiotics was challenged with 0.5 McFarland′s standard of overnight cultures of common bacteria that cause infections. The mixture was sub cultured at 30 minutes, 1 hour and lastly 2 hour intervals. The plates were read the following day for evidence of growth. Result:Overnight incubation yielded growth of the various organisms that were inoculated. Conclusion:Breast milk does not have in vitro antibacterial effect although it may possess same in vivo with the synergistic effect of other substances in the body.

  2. Nucleotides, Nucleosides, and Nucleobases

    DEFF Research Database (Denmark)

    Jensen, Kaj Frank; Dandanell, Gert; Hove-Jensen, Bjarne

    2008-01-01

    We review literature on the metabolism of ribo- and deoxyribonucleotides, nucleosides, and nucleobases in Escherichia coli and Salmonella,including biosynthesis, degradation, interconversion, and transport. Emphasis is placed on enzymology and regulation of the pathways, at both the level of gene...

  3. Effects of antibacterial dishwashing liquid on foodborne pathogens and competitive microorganisms in kitchen sponges

    NARCIS (Netherlands)

    Kusumaningrum, H.D.; Putten, van M.M.; Rombouts, F.M.; Beumer, R.R.

    2002-01-01

    In response to increasing concern about home hygiene, the use of antibacterial products to reduce microorganisms in kitchen sponges and cleaning cloths is strongly promoted by some producers of detergent for domestic use. The effects of an antibacterial dishwashing liquid on Escherichia coli, Salmon

  4. Antibacterial and antiprotozoal effect of Artemisia annua extracts

    DEFF Research Database (Denmark)

    Ivarsen, E.; Fretté, X. C.; Engberg, R. M.;

    2012-01-01

    be banned in the EU. Extracts of aerial parts of Artemisia annua (AA) showed antimicrobial activity in overnight cultures of CP strains isolated from diseased broilers. The hexane extract (HEX) gave the strongest inhibition (MIC=185ppm) while the dichloromethane extract (DCM) gave a weaker inhibition (MIC......=270ppm). The dietary incorporation of HEX reduced the population of CP and the severity of the associated small intestinal lesions (P>0.05) in broilers when applying a NE disease model. The antibacterial compounds from HEX and DCM, chrysosplenol and ponticaepoxide, were isolated. This is the first...... report of activity against CP for these compounds. HEX, DCM and artemisinin were also tested against HM. The two latter showed highest antiprotozoal effect in vitro (MLC=1.0mg/ml and IC50=1.3mg/ml respectively), and were tested in vivo in infected poultry. However, no effect against HM at the given...

  5. The Antibacterial Effect of Silver-carrying B2O3-SiO2-Na2O Glass Material

    Institute of Scientific and Technical Information of China (English)

    XU Ying; CHENG Jinshu; LI Xi; GAO Deqiang; LIU Xiaoming

    2005-01-01

    The antibacterial effect of carrying silver B2O3-SiO2-Na2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B2O3-SiO2-Na2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell's growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.

  6. Long term adverse effects related to nucleoside reverse transcriptase inhibitors: clinical impact of mitochondrial toxicity.

    Science.gov (United States)

    Maagaard, Anne; Kvale, Dag

    2009-01-01

    Antiretroviral treatment (ART) has provided excellent clinical efficacy in HIV infection, and individuals treated for HIV might therefore expect normal duration of life. However, this enthusiasm might be moderated by some devastating long-term adverse effects that are frequently observed in HIV-infected individuals, phenomena that may be even more pronounced as the HIV-infected populations become older and therefore perhaps more susceptible to some of these adverse effects. We here review the clinical impact of mitochondrial toxicity giving rise to many of the adverse effects caused by ART.

  7. Effect of dyeing on antibacterial efficiency of silver coated cotton fabrics

    Science.gov (United States)

    Shahidi, Sheila; Rezaee, Sahar; Hezavehi, Emadaldin

    2014-04-01

    Despite numerous investigations during recent decades in the field of antimicrobial treating textile fibers using silver, many obscurities remain regarding the durability and dyeing ability and the influences of dyeing on the antimicrobial effectiveness of silver-treated fibers. In this research work, the cotton fabrics were sputtered using DC magnetron sputtering system for different times of exposure by silver. Then the silver coated samples were dyed by different classes of synthetic and natural dyes. The dye ability of coated samples was compared with untreated cotton. The reflective spectrophotometer was used for this purpose. The morphology of the cotton fabrics before and after dyeing was observed using a scanning electron microscope (SEM). The antibacterial activity of samples before and after dyeing, were investigated and compared. For antibacterial investigation, the antibacterial counting tests were used. It was concluded that, dyeing does not have any negative effect on antibacterial activity of coated samples and very good antibacterial activity was achieved after dyeing.

  8. An update on the synthesis and antibacterial effects of carbapenems.

    Science.gov (United States)

    Galal, Ahmed M; Gul, Waseem; Noreddin, Ayman M; Slade, Desmond

    2010-01-01

    The double-edged sword of antibiotic use in the fight against disease has saved countless lives at the cost of an escalation in pathogenic bacteria with increased resistance to multiple antibiotic classes. Reduction of resistance is a complicated multi-step endeavor that requires a sustained international effort of reduced utilization, infection control and development of effective and economical antimicrobial agents. The carbapenems are beta-lactam antibiotics that are stable to most beta-lactamases. They have potent bactericidal activity against a wide range of Gram-positive and Gram-negative aerobic bacteria as well as against anaerobic bacteria, while being safe, efficacious and tolerable. The use of carbapenems in hospitals has therefore been restricted to the empirical treatment of critical patients with a variety of serious infections, e.g., nosocomial pneumonia, septicemia, meningitis and cystic fibrosis. This article reviews patents claiming carbapenem antibacterial agents published from 2004-2008.

  9. Antibacterial effectiveness of peracetic acid and conventional endodontic irrigants.

    Science.gov (United States)

    Guerreiro-Tanomaru, Juliane Maria; Morgental, Renata Dornelles; Faria-Junior, Norberto Batista; Berbert, Fábio Luis Camargo Vilela; Tanomaru-Filho, Mário

    2011-01-01

    This study evaluated the in vitro antibacterial activity of conventional and experimental endodontic irrigants against Enterococcus faecalis. The following substances were evaluated by direct contact test: 2.5% sodium hypochlorite (NaOCl); 2% chlorhexidine (CHX); 1% peracetic acid. After different contact periods (30 s, 1, 3, and 10 min), a neutralizing agent was applied. Serial 10-fold dilutions were prepared and plated onto tryptic soy agar (TSA) and the number of colony-forming units per milliliter (CFU/mL) was determined. Sterile saline was used as a negative control. Both 2.5% NaOCl and 2% CHX eliminated E. faecalis after 30 s of contact. Peracetic acid reduced the bacterial counts by 86% after 3 min and completely eliminated E. faecalis after 10 min. These results allow us to conclude that 1% peracetic acid is effective against E. faecalis, despite its slower action compared with 2.5% NaOCl and 2% CHX.

  10. MINERAL PROFILE EVOLUTION OF SOME MEDICINAL PLANTS WITH ANTIBACTERIAL EFFECTS

    OpenAIRE

    2016-01-01

    Individual minerals and antibacterial activity were investigated in 5 medicinal plants (pot marigold - Calendula officinalis, burdock - Arctium lappa, celandine - Chelidonium majus, basil- Ocimum basilicum, thyme - Thymus vulgaris) using Atomic Absorption Spectroscopy (AAS) technique and antibiogram  method. The antibacterial susceptibility has been evaluated over 12 strains isolated from milk microflora, belonging to Staphylococcus, Vibrio, Serratia and Bacillus genera. The obtained results ...

  11. Stereodifferentiation--the effect of P chirality of oligo(nucleoside phosphorothioates) on the activity of bacterial RNase H.

    Science.gov (United States)

    Koziolkiewicz, M; Krakowiak, A; Kwinkowski, M; Boczkowska, M; Stec, W J

    1995-01-01

    P stereoregular phosphorothioate analogs of pentadecamer 5'-d(AGATGTTTGAGCTCT)-3' were synthesized by the oxathiaphospholane method. Their diastereomeric purity was assigned by means of enzymatic degradation with nuclease P1 and, independently, with snake venom phosphodiesterase. DNA-RNA hybrids formed by phosphorothioate oligonucleotides (PS-oligos) with the corresponding complementary pentadecaribonucleotide were treated with bacterial RNase H. The DNA-RNA complex containing the PS-oligo of [all-RP] configuration was found to be more susceptible to RNase H-dependent degradation of the pentadecaribonucleotide compared with hybrids containing either the [all-SP] counterpart or the so called 'random mixture of diastereomers' of the pentadeca(nucleoside phosphorothioate). This stereodependence of RNase H action was also observed for a polyribonucleotide (475 nt) hybridized with these phosphorothioate oligonucleotides. The results of melting studies of PS-oligo-RNA hybrids allowed a rationalization of the observed stereodifferentiation in terms of the higher stability of heterodimers formed between oligoribonucleotides and [all-RP]-oligo(nucleoside phosphorothioates), compared with the less stable heterodimers formed with [all-SP]-oligo(nucleoside phosphorothioates) or the random mixture of diastereomers. Images PMID:8559657

  12. Protective effect of taurine on hypochlorous acid toxicity to nuclear nucleoside triphosphatase in isolated nuclei from rat liver

    Institute of Scientific and Technical Information of China (English)

    Ju-Xiang Li; Yong-Zheng Pang; Chao-Shu Tang; Zai-Quan Li

    2004-01-01

    AIM: Taurine has been shown to be an effective scavenger of hypochlorous acid (HOCI). The role of HOCI is well established in tissue damage associated with inflammation and injury. In the present study, the effect of HOCI on nuclear nucleoside triphosphatase of hepatocytes and the ability of taurine to prevent this effect were investigated.METHODS: Isolated hepatic nuclei from rat liver were exposed to HOCI with or without taurine. The NTPase activity on nuclear envelope was assayed using ATP and GTP as substrates, respectively.RESULTS: The first series of experiments evaluated the toxicity of HOCl and the efficacy of taurine to protect NTPase.HOCI at 10-9-5×10-6 mol/L reduced nuclear NTPase activities in a concentration dependent manner (ATP and GTP as substrates) (P<0.01). HOCI at 10-6 mol/L reduced the NTPase activity by 65% (ATP as substrate) and 76% (GTP as substrate). Taurine (10-7 to 10-4 mol/L) was tested for protection against HOCI at 10-6 mol/L and the nuclei treated with 5x10-4 mol/L taurine exhibited only 20% and 12% reduction in NTPase activities compared to untreated controls. A second study was performed comparing taurine to glutathione (GSH). GSH and HOCI at 10-6 mol/L exhibited 46% and 67.4% reduction in NTPase activities compared with control. GSH (10-4 mol/L) which was incubated with the nuclei and HOCi still exhibited 44.2% and 44.8% reduction in NTPase activities of untreated control. Taurine with HOCI only exhibited 15.2% and 17.1% reduction in NTPase activities, which provided more powerful protection against HOCI than GSH. The third experiment was undertaken to evaluate the specificity of taurine against HOCI. Incubation of rat hepatic nuclei with Fe3+/H2O2 (1 m mol/L vS 5μ mol/L) resulted in a decrease in nuclear NTPase activities (P<0.01).When hepatic nuclei were incubated with Tau (10-4 mol/L) and Fe3+/H2O2 (1m mol/L vS 5μ mol/L), nuclear NTPase activities were only slightly increased as compared with that of incubation with Fe3+/H

  13. 沙葱提取物抗菌效果的研究%Antibacterial Effect of Extracts from Allium mongolicum Regel

    Institute of Scientific and Technical Information of China (English)

    李亚蕾; 罗瑞明

    2008-01-01

    [Objective] Study on antibacterial activity and stability of the ethanol extracts from Allium mongolicum Regel. [Method] Taking Allium mongolicum Regel.(AMR) as experimental material, the antibacterial and stability test, antibacterial capacity and antibacterial activity substance stability of extracts were studied. [Result] Size order of antibacterial effect of extracts on these 5 strains tended to be:Saccharomyces cerevisiae > Penicillium sp.> Aspergillusniger> Staphylococcusaureus> Escherichia coli; under neutral or slight alkaline conditions, optimum antibacterial effect presented best; and UV light irradiation basically had no influence on tested strains. [Conclusion] Antibacterial effect of ethanol extract shows great difference among these strains, and antibacterial activity substance is of good heat and UV light stability.

  14. EFFECTS OF COPPER ION IMPLANTATION ON ANTIBACTERIAL ACTIVITY OF AISI420 STAINLESS STEEL

    Institute of Scientific and Technical Information of China (English)

    Z.G. Dan; H.W. Ni; B.F. Xu; J. Xiong; P. Y. Xiong

    2005-01-01

    Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2.0×1017ions .cm-2. The saturation dose of Cu implantation in AISI420 SS and Cu surface concentration were calculated at the energy of 100keV. The effect of dose on the antibacterial activity was analyzed. Results of antibacterial test show that the saturation dose is the optimum implantation dose for best antibacterial activity, which is above 99% against both Escherichia coli and Staphylococcus aureus. Novel phases such as Fe4Cu3 and Cu9.9Fe0.1 were found in the implanted layer by glancing angle X-ray diffraction (GXRD). The antibacterial activity of AISI420 SS attributes to Cu-contained phase.

  15. Synthesis of methacrylate monomers with antibacterial effects against S. mutans.

    Science.gov (United States)

    He, Jingwei; Söderling, Eva; Österblad, Monica; Vallittu, Pekka K; Lassila, Lippo V J

    2011-11-23

    A series of polymerizable quaternary ammonium compounds were synthesized with the aim of using them as immobilized antibacterial agents in methacrylate dental composites, and their structures were characterized by FT-IR, (1)H-NMR, and (13)C-NMR analysis. Their antibacterial activities against the oral bacterium Streptococcus mutans were evaluated in vitro by a Minimum Inhibitory Concentration test, and the results showed that 2-dimethyl-2-hexadecyl-1-methacryloxyethyl ammonium iodide (C16) had the highest antibacterial activity against S. mutans, and 2-dimethyl-2-pentyl-1-methacryloxyethyl ammonium iodide (C5) and 2-dimethyl-2-octyl-1-methacryloxyethyl ammonium iodide (C8) did not show any inhibition.

  16. Thermodynamic Study on Antibacterial Effect of Different Extracts from Radix Isatis

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To study and analyze the antibacterial effects of different extracts from Radix Isatis. Methods: Staphylococcus aureus was used as the studied object in the experiment. Antibacterial effects of extracts from Radix Isatis were observed by thermocalrimetry on Staphylococcus aureus, together with common pharmacological experiments. Results: The total extract, ethyl acetate (EtOAc) extract, n-butylalcohol (nBuOH) extract, chloroform (CHCl3) extract and petroleum (P. E. ) extract had antiviral effects to some extent while the residue after extracting had no antibacterial activity. The potency of antiviral activity among them was as follows: nBuOH extract > EtOAc extract > CHCl3 extract> total extract >P. E. extract. Conclusion: The antibacteriall effects of Radix Isatis were not limited to any active portion, showing that Radix Isatis exerts its antibacterial effects by cooperation of different active fractions in varied ways.

  17. Nucleoside phosphorylation in amide solutions

    Science.gov (United States)

    Schoffstall, A. M.; Kokko, B.

    1978-01-01

    The paper deals with phosphorylation in possible prebiotic nonaqueous solvents. To this end, phosphorylation of nucleosides using inorganic phosphates in amide solutions is studied at room and elevated temperatures. Reaction proceeds most readily in formamide and N-methylformamide. Products obtained at elevated temperature are nucleotides, nucleoside 2',3'-cyclic phosphates, and when the phosphate concentration is high, nucleoside diphosphates. At room temperature, adenosine afforded a mixture of nucleotides, but none of the cyclic nucleotide. Conditions leading to the highest relative percentage of cyclic nucleotide involve the use of low concentrations of phosphate and an excess of nucleoside.

  18. Antibacterial effect of plant extracts against Helicobacter pylori.

    Science.gov (United States)

    Nostro, A; Cellini, L; Di Bartolomeo, S; Di Campli, E; Grande, R; Cannatelli, M A; Marzio, L; Alonzo, V

    2005-03-01

    The aim of this work was to evaluate the antibacterial effect of plant extracts as alternative and[sol ]or as active agents supporting antibiotics for treating Helicobacter pylori infection. The effect of either, ethanolic or aqueous extracts from 17 plant materials were studied against one H. pylori standard strain and 11 clinical isolates using a disc diffusion test and by evaluating the minimum inhibitory concentration (MIC) on solid media. An inhibitory activity against H. pylori strains was recorded in a large percentage of tested plants. MIC values of ethanolic extracts were from two to four concentration steps lower than the aqueous ones. In particular, ethanolic extracts of Cuminum cyminum L. and Propolis expressed MIC90 values of 0.075 mg/mL. The results show a significant in vitro effect of plant extracts against H. pylori that could be considered a valuable support in the treatment of the infection and may contribute to the development of new and safe agents for inclusion in anti-H. pylori regimens.

  19. Antibacterial effect of Turkish black cumin ( Nigella sativa L. oils

    Directory of Open Access Journals (Sweden)

    Gecgel, Umit

    2005-12-01

    Full Text Available A series of five different oils from Turkish black cumin ( Nigella sativa used in foods mainly for their flavour, preservation and natural therapies were screened for their antibacterial effects at 0.5 %, 1.0 % and 2.0 % concentrations using the agar diffusion method against twenty four pathogenic, spoilage and lactic acid bacteria (LAB. All tested oils showed antibacterial activity against all the bacteria used in the assay. The oils at 2.0 % concentration were more effective than of the other concentrations. The most sensitive bacterium against all of the oil concentrations was Aeromonas hydrophila, while the most resistant was Yersinia enterocolitica. Generally, lactic acid bacteria had more resistance than pathogenic and spoilage bacteria against black cumin oils. Consequently, black cumin oil may be used as an antimicrobial agent in food products to prevent spoilage.Se ensayaron un total de cinco aceites diferentes de comino negro turco ( Nigella sativa L., que se utilizan habitualmente en alimentos para darles sabor, ayudar a la conservación o por sus efectos terapéuticos, para estudiar sus propiedades antimicrobianas a concentraciones de 0.5 %, 1.0 %, y 2 %. Para ello se utilizó el método de difusión en agar, frente a veinticuatro microorganismos patógenos, causantes de alteraciones o bacterias ácido lácticas (LAB. Todos los aceites ensayados mostraron actividad antimicrobiana contra todos los microorganismos ensayados, siendo las concentraciones del 2 % las concentraciones más eficaces. Aeromonas hydrophyla fue el microorganismo mas sensible a todas las concentraciones mientras que Yersinia enterocolitica fue la más resistente. Generalmente las bacterias acido lácticas tuvieron más resistencia que los gérmenes patógenos y las bacterias que causan alteraciones. En consecuencia, el aceite de comino negro turco se puede utilizar como agente antimicrobiano en productos alimenticios para evitar su alteración.

  20. Antibacterial effect of Turkish black cumin ( Nigella sativa L. ) oils

    OpenAIRE

    Gecgel, Umit; Sagdic, Osman; Arici, Muhammet

    2005-01-01

    A series of five different oils from Turkish black cumin ( Nigella sativa ) used in foods mainly for their flavour, preservation and natural therapies were screened for their antibacterial effects at 0.5 %, 1.0 % and 2.0 % concentrations using the agar diffusion method against twenty four pathogenic, spoilage and lactic acid bacteria (LAB). All tested oils showed antibacterial activity against all the bacteria used in the assay. The oils at 2.0 % concentration were more effective than of the ...

  1. The Antibacterial Effects of Apacaries Gel on Streptococcus mutans: An in vitro Study

    OpenAIRE

    Juntavee, Apa; Peerapattana, Jomjai; Ratanathongkam, Ariya; Nualkaew, Nartsajee; Chatchiwiwattana, Supaporn; Treesuwan, Panta

    2014-01-01

    ABSTRACT Background: New approaches for chemomechanical caries removal require effective materials with antibacterial properties for removal of infected dentin. Apacaries gel is a newly developed material comprised polyphenol from mangosteen extracts and papain mixed in gel preparation. Aim: This study evaluated the antibacterial effects of Apacaries gel on Streptococcus mutans in vitro. Materials and methods: Mangosteen pericarp powder was extracted. The amount of phenolic compounds was dete...

  2. Antibacterial effect of silver nanofilm modified stainless steel surface

    Science.gov (United States)

    Fang, F.; Kennedy, J.; Dhillon, M.; Flint, S.

    2015-03-01

    Bacteria can attach to stainless steel surfaces, resulting in the colonization of the surface known as biofilms. The release of bacteria from biofilms can cause contamination of food such as dairy products in manufacturing plants. This study aimed to modify stainless steel surfaces with silver nanofilms and to examine the antibacterial effectiveness of the modified surface. Ion implantation was applied to produce silver nanofilms on stainless steel surfaces. 35 keV Ag ions were implanted with various fluences of 1 × 1015 to 1 × 1017 ions•cm-2 at room temperature. Representative atomic force microscopy characterizations of the modified stainless steel are presented. Rutherford backscattering spectrometry spectra revealed the implanted atoms were located in the near-surface region. Both unmodified and modified stainless steel coupons were then exposed to two types of bacteria, Pseudomonas fluorescens and Streptococcus thermophilus, to determine the effect of the surface modification on bacterial attachment and biofilm development. The silver modified coupon surface fluoresced red over most of the surface area implying that most bacteria on coupon surface were dead. This study indicates that the silver nanofilm fabricated by the ion implantation method is a promising way of reducing the attachment of bacteria and delay biofilm formation.

  3. Thymol nanospheres as an effective anti-bacterial agent.

    Science.gov (United States)

    Wattanasatcha, Anna; Rengpipat, Sirirat; Wanichwecharungruang, Supason

    2012-09-15

    Among thymol, carvacrol, citronellal, eugenol and terpinen-4-ol, thymol showed the highest antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Thymol was then encapsulated into water dispersible submicron sized ethylcellulose/methylcellulose spheres, attaining the relatively high thymol loading level of 43.53% (weight of encapsulated thymol to weight of the thymol-loaded spheres). When tested against the same three bacterial strains, the encapsulated thymol gave comparable minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values to the unencapsulated compound while mostly showing lower MIC and MBC values than the conventionally used preservative, methyl-p-hydroxybenzoate (methylparaben). The use of encapsulated thymol at 0.078, 0.156 and 0.625 mg ml(-1) (0.52, 1.04 and 4.16 mmol(-1), respectively) in cosmetic lotion formulations provided total suppression of viable E. coli, S. aureus and P. aeruginosa growth (all initially seeded at 10(5) cfu ml(-1)), respectively, over the three month test period, whereas unencapsulated thymol showed effective suppression for only 2-4 weeks. Effective bacterial suppression by encapsulated thymol was also observed when used in cream and aqueous gel cosmetic formulations.

  4. Toxic effects of nucleoside reverse transcriptase inhibitors on the liver. Value of electron microscopy analysis for the diagnosis of mitochondrial cytopathy.

    Science.gov (United States)

    Duong Van Huyen, Jean-Paul; Landau, Alain; Piketty, Christophe; Bélair, Marie-France; Batisse, Dominique; Gonzalez-Canali, Gustavo; Weiss, Laurence; Jian, Raymond; Kazatchkine, Michel D; Bruneval, Patrick

    2003-04-01

    Nucleoside reverse transcriptase inhibitors (NRTIs) induce mitochondrial toxic effects resulting in multiple organ disorders. Liver involvement has been associated mainly with severe lactic acidosis and massive steatosis. However, patients with HIV infection who are receiving antiretroviral treatment frequently have mildly abnormal liver test results that, to date, have not been linked unambiguously to the toxic effects of NRTIs. Thirteen patients with HIV infection treated with NRTI-based regimens had low-grade abnormal liver test results associated with digestive and nonspecific general symptoms. Histologic examination of liver samples showed diffuse steatosis in only 6 cases and mild steatosis in the remaining cases, associated with megamitochondria, mild lobular inflammation and necrosis, Mallory bodies, and perisinusoidal fibrosis. In all cases, ultrastructural study disclosed mitochondrial abnormalities. Our work demonstrates that NRTI-induced toxic effects in the liver may occur as indolent nonspecific disease with variable histologic features and emphasizes the diagnostic value of electron microscopy, particularly when diffuse steatosis is absent.

  5. Study on Antibacterial Effect of Medlar and Hawthorn Compound Extract In Vitro

    OpenAIRE

    Niu, Yang; Nan, Yi; Yuan, Ling; Wang, Rong

    2013-01-01

    This paper evaluated the antibacterial effect of medlar and hawthorn compound extract in vitro. Water extract method and ethanol extraction method was adopted to prepare the compound extracts, and disc diffusion method and improved test tube doubling dilution method were used to conduct the antibacterial test on the two common pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumonia, in vitro. The results showed that medlar and hawthorn compound extract was moderately sensitive to ...

  6. Is the effect of surface modifying molecules on antibacterial activity universal for a given material?

    Science.gov (United States)

    Hsu, Alexander; Liu, Fangzhou; Leung, Yu Hang; Ma, Angel P. Y.; Djurišić, Aleksandra B.; Leung, Frederick C. C.; Chan, Wai Kin; Lee, Hung Kay

    2014-08-01

    Antibacterial activity of nanomaterials is strongly dependent on their properties, and their stability and toxicity can be varied using surface coatings. We investigated the effect of different surface modifying molecules on the antibacterial properties of two ZnO nanoparticle samples. We found that the starting surface properties of the nanoparticles have significant effects on the attachment of the surface modifying molecules and consequent antibacterial activity. Two out of five investigated surface modifying molecules not only had a significant difference in the magnitude of their effect on different nanoparticles, but also resulted in the opposite effects on two ZnO nanoparticle samples (an enhancement of antibacterial activity for one and a reduction of antibacterial activity for the other ZnO sample). This indicates that no general rule on the effect of a specific molecule on the toxicity of a metal oxide nanoparticle can be derived without knowing the nanoparticle properties, due to the fact that surface modifier attachment onto the surface is affected by the initial surface properties.Antibacterial activity of nanomaterials is strongly dependent on their properties, and their stability and toxicity can be varied using surface coatings. We investigated the effect of different surface modifying molecules on the antibacterial properties of two ZnO nanoparticle samples. We found that the starting surface properties of the nanoparticles have significant effects on the attachment of the surface modifying molecules and consequent antibacterial activity. Two out of five investigated surface modifying molecules not only had a significant difference in the magnitude of their effect on different nanoparticles, but also resulted in the opposite effects on two ZnO nanoparticle samples (an enhancement of antibacterial activity for one and a reduction of antibacterial activity for the other ZnO sample). This indicates that no general rule on the effect of a specific

  7. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Yudovin-Farber, Ira [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel); Beyth, Nurit; Weiss, Ervin I. [Hebrew University of Jerusalem, Department of Prosthodontics, Faculty of Dentistry (Israel); Domb, Abraham J., E-mail: avid@ekmd.huji.ac.i [Hebrew University of Jerusalem, Department of Medicinal Chemistry and Natural Products, School of Pharmacy, Faculty of Medicine (Israel)

    2010-02-15

    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  8. Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

    Science.gov (United States)

    Yudovin-Farber, Ira; Beyth, Nurit; Weiss, Ervin I.; Domb, Abraham J.

    2010-02-01

    Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

  9. Synthesis of Methacrylate Monomers with Antibacterial Effects Against S. Mutans

    Directory of Open Access Journals (Sweden)

    Jingwei He

    2011-11-01

    Full Text Available A series of polymerizable quaternary ammonium compounds were synthesized with the aim of using them as immobilized antibacterial agents in methacrylate dental composites, and their structures were characterized by FT-IR, 1H-NMR, and 13C-NMR analysis. Their antibacterial activities against the oral bacterium Streptococcus mutans were evaluated in vitro by a Minimum Inhibitory Concentration test, and the results showed that 2-dimethyl-2-hexadecyl-1-methacryloxyethyl ammonium iodide (C16 had the highest antibacterial activity against S. mutans, and 2-dimethyl-2-pentyl-1-methacryloxyethyl ammonium iodide (C5 and 2-dimethyl-2-octyl-1-methacryloxyethyl ammonium iodide (C8 did not show any inhibition.

  10. Antibacterial effects of electrospun chitosan/poly(ethylene oxide) nanofibrous membranes loaded with chlorhexidine and silver.

    Science.gov (United States)

    Song, Jiankang; Remmers, Stefan J A; Shao, Jinlong; Kolwijck, Eva; Walboomers, X Frank; Jansen, John A; Leeuwenburgh, Sander C G; Yang, Fang

    2016-07-01

    To prevent percutaneous device associated infections (PDAIs), we prepared electrospun chitosan/poly(ethylene oxide) (PEO) nanofibrous membrane containing silver nanoparticles as an implantable delivery vehicle for the dual release of chlorhexidine and silver ions. We observed that the silver nanoparticles were distributed homogeneously throughout the fibers, and a fast release of chlorhexidine in 2days and a sustained release of silver ions for up to 28days. The antibacterial efficacy of the membranes against Staphylococcus aureus showed that the membranes exhibited an obvious inhibition zone upon loading with either chlorhexidine (20μg or more per membrane) or AgNO3 (1 and 5wt% to polymer). Furthermore, long-term antibacterial effect up to 4days was verified using membranes containing 5wt% AgNO3. The results suggest that the membranes have strong potential to act as an active antibacterial dressing for local delivery of antibacterial agents to prevent PDAIs.

  11. EFFECT OF COPPER IMPLANTATION ON ANTIBACTERIAL ACTIVITY OF AUSTENITIC STAINLESS STEEL

    Institute of Scientific and Technical Information of China (English)

    J. Xiong; B.F. Xu; H.W. Ni; P.Y. Xiong; Z.G. Dan

    2004-01-01

    Antibacterial activity has been studied by copper ion implantation into 0Cr18Ni9 stainless steel.Ions extracted from a metal vapor vacuum arc (MEWA) are sourced with 60-100keV energy and a dose range (0.2-2.0)×1017 ions cm-2. Saturation doses, surface concentration were calculated and the relationships between energy, dose and antibacterial activity were analyzed.Novel phases such as Fe4Cu3 and Cu0.81Ni0-19 were found after copper implantation by X-ray diffraction. The novel phases effects on antibacterial activity have been investigated. The results show that saturation dose varies with the ions′energy. Antibacterial activity has close relation with copper's concentration in implanted layer and Cu-rich phase.

  12. Antibacterial effect of cationic porphyrazines and anionic phthalocyanine and their interaction with plasmid DNA

    Science.gov (United States)

    Hassani, Leila; Hakimian, Fatemeh; Safaei, Elham; Fazeli, Zahra

    2013-11-01

    Resistance to antibiotics is a public health issue and identification of new antibacterial agents is one of the most important goals of pharmacological research. Among the novel developed antibacterial agents, porphyrin complexes and their derivatives are ideal candidates for use in medical applications. Phthalocyanines differ from porphyrins by having nitrogen atoms link the individual pyrrol units. The aza analogues of the phthalocyanines (azaPcs) such as tetramethylmetalloporphyrazines are heterocyclic Pc analogues. In this investigation, interaction of an anionic phthalocyanine (Cu(PcTs)) and two cationic tetrapyridinoporphyrazines including [Cu(2,3-tmtppa)]4+ and [Cu(3,4-tmtppa)]4+ complexes with plasmid DNA was studied using spectroscopic and gel electrophoresis methods. In addition, antibacterial effect of the complexes against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria was investigated using dilution test method. The results indicated that both porphyrazines have significant antibacterial properties, but Cu(PcTs) has weak antibacterial effect. Compairing the binding of the phthalocyanine and the porphyrazines to DNA demonstrated that the interaction of cationic porphyrazines is stronger than the anionic phthalocyanine remarkably. The extent of hypochromicity and red shift of absorption spectra indicated preferential intercalation of the two porphyrazine into the base pairs of DNA helix. Gel electrophoresis result implied Cu(2,3-tmtppa) and Cu(3,4-tmtppa) are able to perform cleavage of the plasmid DNA. Consequently, DNA binding and cleavage might be one of the antibacterial mechanisms of the complexes.

  13. Effect of lattice constant of zinc oxide on antibacterial characteristics.

    Science.gov (United States)

    Yamamoto, Osamu; Komatsu, Miyako; Sawai, Jun; Nakagawa, Zenbe-E

    2004-08-01

    Zinc oxide powders were heated in different atmospheres at 800 and 1400 degrees C, of which the characterization and the antibacterial activity were studied by X-ray diffractometry and the measurement of the change in electrical conductivity with bacterial growth. The diffraction peaks corresponding to zinc oxide with hexagonal type structure were detected in all samples, which shifted in low-angle side with the increase in the oxidizability of atmosphere during heat-treatment. From the results of calculating lattice constants, a0 and c0, it was found that the value of c0 in hexagonal structure increased with the increase in the oxidizability of atmosphere. On the samples heated at 1400 degrees C, the changes of the c0 value were less than those at 800 degrees C. However, no change of the a0 value showed, irrespective of atmosphere and temperature. Hydrogen peroxide that contributes to the occurrence of antibacterial activity was found to generate from all samples, and the generation amount increased with the increase of c0 value; incidently the amount in the samples heated at 1400 degrees C was less than that at 800 degrees C. The antibacterial activity of zinc oxide increased with the increase of c0 value; that is, it was found that the value of c0 in crystal structure affected the antibacterial activity of zinc oxide.

  14. The Antibacterial Effect of CMCTS-Containing Chewing Gum

    Institute of Scientific and Technical Information of China (English)

    Dagang Miao; Dan Blom; Hongmei Zhao; Xuefei Luan; Tongzhi Chen; Xiaohui Wu; Ning Song

    2009-01-01

    Objective:This paper was designed to confirm the efficacy of chewing carboxymethyl chitosan(CMCTS)-containing gum in suppressing the growth of oral bacteria when compared to a CMCTS-containing mouth rinse.Methods:Fourteen healthy subjects were recruited from among the staff and students of Qingdao University Dentistry Department.Before the experiments saliva was collected from all subjects and bacteria counts determined.For the gum study,the subjects chewed CMCTS-containing gum for 5 rain and then rested for 5 min.When testing the CMCTS mouth rinse,the subjects gargled with 10 mL of solution for 30 s,followed by resting for 9min 30 s.These protocols were repeated five times over a 50 rain period on the same day.Post-experiment saliva samples were then collected at the following times:0,30 and 60 min.Results:Chewing gum containing CMCTS or rinsing with a CMCTS-containing rinse significantly decreased oral bacteria counts.The total bacteria counts,total Streptococci counts,and mutans streptococci counts of saliva from subjects who chewed CMCTS-containing gum were significantly lower than saliva from subjects in the rinse group in all three sampling periods,except in the case of the total bacteria count in the 60 min samples.Conclusion:CMCTS-containing gum chewing has a greater antibac-terial effect than using a CMCTS-containing mouth rinse.The present findings strongly indicate that the application of natural materials such as chitosan and its derivatives is useful for better oral health.

  15. Effects of antibacterial peptide on cellular immunity in weaned piglets.

    Science.gov (United States)

    Ren, Z H; Yuan, W; Deng, H D; Deng, J L; Dan, Q X; Jin, H T; Tian, C L; Peng, X; Liang, Z; Gao, S; Xu, S H; Li, G; Hu, Y

    2015-01-01

    The aim of this study was to evaluate the effects of antibacterial peptide (ABP) sufficiency on cellular immune functions by determining the spleen cell cycle and apoptosis, peripheral blood T cell subsets, and T cell proliferation function in weaned piglets. A total of 90 piglets (Duroc × Landrace × Yorkshire) of both sexes were randomly allotted to 5 dietary treatments. Each treatment consisted of 3 replicates with 6 piglets per replicate. The dietary treatments consisted of the negative control (NC; basal diet), positive control (PC; basal diet supplemented with 400 mg/kg Astragalus polysaccharide), and ABP (basal diet mixed with 250, 500, and 1,000 mg/kg ABP). The experimental lasted for 28 d. Two piglets from each replicate were selected randomly for blood samples extraction from the jugular vein to obtain peripheral blood T cell subsets, and T cell proliferation function analysis was performed on d 32, 39, 46, and 53. Two piglets from each replicate were selected and euthanized to observe the spleen cell cycle and apoptosis on d 39 and 53. In ABP-sufficient piglets, the G0/G1 phase of the spleen cell cycle was much lower (P ABP sufficiency (P ABP-sufficient piglets. Percentages of CD3 (+) and CD3 (+)CD4 (+) ratios (d 39, 46, and 53) and CD4 (+)CD8 (+) ratios (d 32, 39, 46, and 53) increased remarkably (P ABP sufficiency compared with NC. These results suggest that ABP sufficiency could increase the T cell population and proliferation function of T cells and could induce decreased percentages of apoptotic cells. Overall, the cellular immune function was evidently improved in weaned piglets. We suggest optimal dosages of 500 mg/kg ABP for 4-wk addition and 1,000 mg/kg ABP for 2-wk addition.

  16. The Nucleoside Uridine Isolated in the Gas Phase**

    Science.gov (United States)

    Peña, Isabel; Cabezas, Carlos; Alonso, José L.

    2016-01-01

    Herein we present the first experimental observation of the isolated nucleoside uridine, placed in the gas phase by laser ablation and characterized by Fourier transform microwave techniques. Free from the bulk effects of their native environments, anti/C2’-endo-g+ conformation has been revealed as the most stable form of uridine. Intramolecular hydrogen bonds involving uracil and ribose moieties have been found to play an important role in the stabilization of the nucleoside. PMID:25683559

  17. [COMPARATIVE ANALYSIS OF ANTIBACTERIAL EFFECT OF PHYTOANTIBIOTICS AND ANTIBIOTICS].

    Science.gov (United States)

    Akhvlediani, L; Koiava, T; Lomtadze, L; Joxadze, M; Msxiladze, L; Berashvili, D; Bakuridze, A

    2016-11-01

    The objective of this study was to determine the antibacterial activity of individual medicines and containing sum of the phyto-extracts against the bacteria causing nosocomial infections in compare to antibiotics. In the investigation were involved four strains of gram-negative bacteria Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and Acinetobacter spp. Each object was investigated on antibiotic resistance using Kirby-Bauer diffusion method on 22 types of antibiotics. The objects of the study were: Sanguinarine, Chelerythrine and Berberine hydrochloride (of lab quality); essential oils and aromatic waters of Eucalyptus, Salvia and Lavanda. For determination their antibacterial activity was used Raits serological dilution method with adaptation. The results show that the antibiotic resistant bacteria did not rise in non-diluted and 1:1 diluted test-tubes. In 1:5 diluted test-tubes was observed a little turbidity and growth, as for in other test-tubes - intensive growth. The investigated phyto-medicines show the higher antibacterial activity than the antibiotics.

  18. Antibacterial effects of sol-gel-derived bioactive glass nanoparticle on aerobic bacteria.

    Science.gov (United States)

    Mortazavi, V; Nahrkhalaji, M Mehdikhani; Fathi, M H; Mousavi, S B; Esfahani, B Nasr

    2010-07-01

    The aim of this work was to evaluate the antibacterial effect of bioactive glass nanopowders. The 58S, 63S, and 72S compositions were prepared via the sol-gel technique. Characterization techniques such as X-ray diffraction, transmission electron microscopy (TEM), Zetasizer, and X-ray fluorescent were used. The antibacterial activity was studied using Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Staphylococcus aureus. Cytotoxicity of the samples was evaluated using mouse fibroblast L929 cell line. The chemical compositions of the prepared samples were as predicted, and the particle size of the samples with an amorphous structure mainly ranged over 20-90 nm. At broth concentrations below 50 mg/mL, they showed no antibacterial activity. The 58S showed the highest antibacterial activity with the minimum bactericidal concentrations of 50 and 100 mg/mL for E. coli plus S. aureus and for P. aeruginosa, respectively. The 63S exhibited bactericidal and bacteriostatic effects on E. coli and S. aureus at concentrations of 100 and 50 mg/mL, respectively, at an minimum bactericidal concentrations of 100 mg/mL. However, 72S bioactive glass nanopowder showed no antibacterial effect. They showed no cytotoxicity. It was concluded that bioactive glass nanopowders could be considered as good candidates for the treatment of oral bone defects and root canal disinfection. (c) 2010 Wiley Periodicals, Inc. J Biomed Mater Res, 2010.

  19. Effects of Lactobacillus plantarum immobilization in alginate coated with chitosan and gelatin on antibacterial activity.

    Science.gov (United States)

    Trabelsi, Imen; Ayadi, Dorra; Bejar, Wacim; Bejar, Samir; Chouayekh, Hichem; Ben Salah, Riadh

    2014-03-01

    The present study aimed to investigate and evaluate the efficiency of immobilizing the Lactobacillus plantarum TN9 strain in alginate using chitosan and gelatin as coating materials, in terms of viability and antibacterial activity. The results indicate that maximum concentrations of L. plantarum TN9 strain were produced with 2% sodium alginate, 10(8)UFC/ml, and 1M calcium chloride. The viability and antibacterial activity of the L. plantarum TN9 cultures before and after immobilization in alginate, chitosan-coated alginate, and gelatin-coated alginate, were studied. The findings revealed that the viability of encapsulated L. plantarum could be preserved more than 5.8 log CFU/ml after 35 day of incubation at 4 °C, and no effects were observed when gelatin was used. The antibacterial activity of encapsulated L. plantarum TN9 against Gram-positive and Gram-negative pathogenic bacteria was enhanced in the presence of chitosan coating materials, and no activity was observed in the presence of gelatin. The effects of catalase and proteolytic enzymes on the culture supernatant of L. plantarum TN9 were also investigated, and the results suggested that the antibacterial activity observed was due to the production of organic acids. Taken together, the findings indicated that immobilization in chitosan enhanced the antibacterial activity of L. plantarum TN9 against several pathogenic bacteria. This encapsulated strain could be considered as a potential strong candidate for future application as an additive in the food and animal feed industries.

  20. Evaluation of Antibacterial Effects of Silver-Coated Stainless Steel Orthodontic Brackets

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    Valiollah Arash

    2016-08-01

    Full Text Available Objectives: White spots and enamel demineralization around orthodontic brackets are among the most important complications resulting from orthodontic treatments. Since the antibacterial properties of metals and metallic particles have been well documented, the aim of this study was to assess the antibacterial effect of stainless steel orthodontic brackets coated with silver (Ag particles.Materials and Methods: In this study, 40 standard metal brackets were divided into two groups of 20 cases and 20 controls. The brackets in the case group were coated with Ag particles using an electroplating method. Atomic force microscopy (AFM and scanning electron microscopy (SEM were used to assess the adequacy of the coating process. In addition, antibacterial tests, i.e., disk diffusion and direct contact tests were performed at three, six, 24and 48 hours, and 15 and 30 days using a Streptococcus mutans strain. The results were analyzed using Student’s t-test and repeated measures ANOVA.Conclusions: Brackets coated with Ag, via an electroplating method, exhibited antibacterial properties when placed in direct contact with Streptococcus mutans. This antibacterial effect persisted for 30 days after contact with the bacteria.

  1. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Dental Materials; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Pedriatric Dentistry], e-mail: rmpuppin@fop.unicamp.br

    2009-07-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm{sup 2} area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  2. Effect of the La alloying addition on the antibacterial capability of 316L stainless steel.

    Science.gov (United States)

    Yuan, J P; Li, W; Wang, C

    2013-01-01

    316L stainless steel is widely used for fashion jewelry but it can carry a large number of bacteria and cause the potential risk of infection since it has no antimicrobial ability. In this paper, La is used as an alloying addition. The antibacterial capability, corrosion resistance and processability of the La-modified 316L are investigated by microscopic observation, thin-film adhering quantitative bacteriostasis, electrochemical measurement and mechanical test. The investigations reveal that the La-containing 316L exhibits the Hormesis effect against Staphylococcus aureus ATCC 25923 and Escherichia coli DH5α, 0.05 wt.% La stimulates their growth, as La increases, the modified 316L exhibits the improved antibacterial effect. The more amount of La is added, the better antibacterial ability is achieved, and 0.42 wt.% La shows excellent antibacterial efficacy. No more than 0.11 wt.% La addition improves slightly the corrosion resistance in artificial sweat and has no observable impact on the processability of 316L, while a larger La content degrades them. Therefore, the addition of La alone in 316L is difficult to obtain the optimal combination of corrosion resistance, antibacterial capability and processability. In spite of that, 0.15 wt.% La around is inferred to be the trade-off for the best overall performance.

  3. Antibacterial Effect of Autologous Platelet-Rich Gel Derived from Subjects with Diabetic Dermal Ulcers In Vitro

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    Lihong Chen

    2013-01-01

    Full Text Available Background. Autologous platelet-rich gel (APG is an effective method to improve ulcer healing. However, the mechanisms are not clear. This study aimed to investigate the antibacterial effect of APG in vitro. Methods. Platelet-rich plasma (PRP, platelet-poor plasma (PPP and APG were prepared from whole blood of sixteen diabetic patients with dermal ulcers. Antibacterial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were evaluated by bacteriostasis assay of APG, PRP, and APG-APO (APG combined with apocynin, with phosphate-buffered saline (PBS and PPP as the control group. Results. (1 Compared to the PBS and PPP, the APG and APG-APO groups showed strong antibacterial activity against Staphylococcus aureus. There was no significant difference (P>0.05 between APG and APG-APO. (2 Compared to PBS, APG, APG-APO, and PRP showed obvious antibacterial effects against Escherichia coli and Pseudomonas aeruginosa. No significant difference (P>0.05 was revealed among the three groups. Compared to the PPP group, they did not show antibacterial effect against Escherichia coli and Pseudomonas aeruginosa (P>0.05. Conclusions. APG has antibacterial effect against Staphylococcus aureus mediated by platelet activation in the diabetic patients with dermal ulcer, and does not present obvious antibacterial effect against Escherichia coli or Pseudomonas aeruginosa. Combination of APG and antibiotics may have synergistic antibacterial effect.

  4. 五种抗菌皂抗菌效果的评价%EVALUATION ON ANTIBACTERIAL EFFECT OF FIVE ANTIBACTERIAL SOAPS

    Institute of Scientific and Technical Information of China (English)

    李晓婷; 姚晨之; 公培龙

    2013-01-01

    目的 评价含有不同抗菌成分香皂的抗菌性能,以了解其质量状况.方法 采用琼脂稀释法,对市售标有抗菌作用的抗菌肥皂的抗菌效果进行了体外抗菌性能评价.结果 浓度为5 000 mg/L的上海药皂、上海硫磺皂、六神艾叶除菌香皂、六神除菌香皂对大肠杆菌、金黄色葡萄球菌和白色念珠菌均有抑制效果,达到广谱抗菌肥皂的要求;浓度为6 000 mg/L的舒服佳橄榄油润肤香皂对白色念珠菌亦无抑制作用.结论 所抽检的五种抗菌肥皂中,只有四种在较高浓度下达到广谱抗菌肥皂的标准.%Objective To evaluate the antimicrobial effect of soaps containing different antibacterial ingredients in order to know the quality status.Method Agar dilution method was used to evaluate the antibacterial or inhibition activities of commercial antibacterial soaps.Results Shanghai medicated soap,Shanghai sulfur soap,Liushen folic artemisiae antibacterial soap and Liushen antibacterial soap have great antibacterial activities against Escherichia coli,Staphylococcus aureus and Candida albicans at the concentration of 5 000 mg/L,which could achieve the requirements of the broad-spectrum antibacterial soap.Safeguard olive oil emollient soaps have no inhibition effect on Candida albicans at the concentration of 6 000 mg/L.Conclusion At higher concentration,only four of five checked antibacterial soaps are up to the standards of the broad-spectrum antibacterial soap.

  5. Effect of plasma superficial treatments on antibacterial functionalization and coloration of cellulosic fabrics

    Science.gov (United States)

    Ibrahim, Nabil A.; Eid, Basma M.; Abdel-Aziz, Mohamed S.

    2017-01-01

    Remarkable improvement in antibacterial activity and durability of different cellulosic substrates namely cotton, linen, viscose and lyocell was achieved by pre-surface modification using N2-plasma to create new active and binding sites, -NH2 groups, onto the modified fabric surfaces followed by subsequent loading of biosynthesized silver nanoparticles (Ag NPs) alone and in combination with certain antibiotics using exhaustion method. The imparted antibacterial activity against both G+ve (S. aureus) and G-ve (E. coli) pathogens was governed by type of substrate, extent of modification and subsequent loading of antibacterial agent, synergistic effect, and antibacterial activity as well as type of harmful bacteria. A remarkable antibacterial activity still retained even after 15 washings. In addition, incorporation of Ag NPs into pigment printing paste and into acid dyeing bath for combined coloration and functionalization of O2-plasma and N2-plasma pre-modified substrates respectively were successfully achieved. Moreover, both SEM images and EDS spectra of selected substrates revealed the change in surface morphology as well as the presence of the loaded Ag element onto the post-treated substrates.

  6. Study of Antibacterial Effect of Novel Thiazole, Imidazole and Tetrahydropyridine Derivatives against Escherichia coli

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    Behzad Ghasemi

    2016-01-01

    Full Text Available > Introduction: Escherichia coli is one of the important pathogens in human with globalimportance. Because of the necessity for identification and the use of novel antibacterialcompounds against E. coli, in this present study we focused on the antibacterial effects ofsynthesized thiazole, imidazole and tetrahydropyridine derivatives on E. coli.Methods: For evaluation of antibacterial effect, the disk diffusion method was applied to measurethe growth inhibition zone diameter and broth micro-dilution was performed to determine theminimum inhibitory concentration (MIC.Results: Assessing the antibacterial effect showed that only 6d derivative of thiazole hadinhibitory effect on E. coli and the other thiazole, imidazole and tetrahydropyridine derivativeslacked any inhibitory result on this organism. The inhibitory effect of 6d derivative of thiazolewas MIC=125 and growth inhibition zone diameter of 16±0.1.Discussion: The antibacterial effect of thiazole, imidazole and tetrahydropyridine derivativesdiffers from each other and chemical linkages such as oxygen to thiazole ring in 6d derivative,could have reinforced this effect. The next step is determination of the toxicity and therapeuticeffects in the laboratory animals.

  7. Synergic Antibacterial Effect of Curcumin with Ampicillin; Free Drug Solutions in Comparison with SLN Dispersions

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    Faezeh Alihosseini

    2016-09-01

    Full Text Available Purpose: This study was designed to investigate benefit of using nanotechnology on increasing of synergic antibacterial effect of natural and chemical antibacterial agents. Methods: At first the MIC and MBC of Curcumin and Ampicillin as selected antibacterial agents was determined, after that Solid Lipid Nanoparticles (SLNs of each active ingredients as well as Curcumin-Ampicillin loaded SLNs were prepared using high pressure homogenization technique. Characterization of prepared SLNs was done, then MIC, MBC and contact killing time were investigated for Curcumin-Ampicillin loaded SLNs in comparison with free Curcumin and Ampicillin solutions as well as Ampicillin and Curcumin SLNs. Results: Based on results nanoparticles with the size of 150 nm show much more decreased MIC and MBC when Ampicillin and Curcumin were loaded together on SLNs than solutions in which free Ampicillin and Curcumin were mixed. Conclusion: It seems that using nanotechnology could cause decrease the dosage of antibiotics and risk of having antibiotic resistance bacteria strains.

  8. Effects of Rare Earth Elements on Photocatalytic Antibacterial Properties of Nanometer TiO2 Powders

    Institute of Scientific and Technical Information of China (English)

    Gao Ning; Liang Jinsheng; Meng Junping; Ou Xiuqin

    2004-01-01

    Nanometer Ce/TiO2 functional materials with photocatalystic antibacterial properties were prepared by dipping TiO2 nanometer powders into RE( NO3 )·nH2O solutions, filtrating, drying and heat treatment, and the enhancement mechanisms of Ce on the nanometer TiO2 were studied by electronic spin resonance(ESR) The results show that TiO2 for photocatalystic antibacterial properties is strengthened evidently by adding Ce, which has a high efficiency of photocatalystic antibacterial properties with the light extent of visible light and ultraviolet radiation. The basic reason for obtaining the strengthened result is that the effective wave length of photocatalystic properties of TiO2 can be expanded to visible light area with the induction of the rare earth elements, whether or not ultraviolet light exists, nanometer TiO2 can produce a great deal of hydroxylic radical(·OH) by treating with rare earth elements.

  9. Synergic Antibacterial Effect of Curcumin with Ampicillin; Free Drug Solutions in Comparison with SLN Dispersions

    Science.gov (United States)

    Alihosseini, Faezeh; Azarmi, Shirzad; Ghaffari, Solmaz; Haghighat, Setareh; Rezayat Sorkhabadi, Seyed Mahdi

    2016-01-01

    Purpose: This study was designed to investigate benefit of using nanotechnology on increasing of synergic antibacterial effect of natural and chemical antibacterial agents. Methods: At first the MIC and MBC of Curcumin and Ampicillin as selected antibacterial agents was determined, after that Solid Lipid Nanoparticles (SLNs) of each active ingredients as well as Curcumin-Ampicillin loaded SLNs were prepared using high pressure homogenization technique. Characterization of prepared SLNs was done, then MIC, MBC and contact killing time were investigated for Curcumin-Ampicillin loaded SLNs in comparison with free Curcumin and Ampicillin solutions as well as Ampicillin and Curcumin SLNs. Results: Based on results nanoparticles with the size of 150 nm show much more decreased MIC and MBC when Ampicillin and Curcumin were loaded together on SLNs than solutions in which free Ampicillin and Curcumin were mixed. Conclusion: It seems that using nanotechnology could cause decrease the dosage of antibiotics and risk of having antibiotic resistance bacteria strains. PMID:27766232

  10. Structure and synergetic antibacterial effect of zinc and cerium carried sodium zirconium phosphates

    Institute of Scientific and Technical Information of China (English)

    YANG Yunhua; DAI Guangjian; TAN Shaozao; LIU Yingliang; SHI Qingshan; OUYANG Yousheng

    2011-01-01

    Zinc and cerium carried zirconium phosphates (Zn-Ce/ZrPs) were prepared by exchanging zinc and cerium cations into sodium zirconium phosphate (NaZrP) through the ion-exchange method and characterized by X-ray diffraction(XRD), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). Furthermore, the specific surface area, zeta potential and antibacterial activity were tested. The results showed that Zn-Ce/ZrPs were with hexagonal crystal system, and the surface area of Zn-Ce/ZrPs increased much more than that of NaZrP. Zn-Ce/ZrPs showed obvious synergetic antibacterial effect, and have the potential to be used as antibacterial agents in environmental control.

  11. Assessing antibacterial effect of filter media coated with silver nanoparticles against Bacillus spp

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    Mahmood Nafisi Bahabadi

    2016-04-01

    Full Text Available Background: Nanotechnology is a field of applied science and technology covering a broad range of topics. Use of nanotechnology and especially silver nanoparticles in control of bacterial diseases and infections has been studied in the recent years. The aim of the present study was to investigate the in vitro antibacterial effect of filter media coated with silver nanoparticles against Bacillus spp. Materials and methods: In this research, first, the antibacterial effects of silver nanoparticles against mentioned bacteria were evaluated by microdilution method in Broth medium. After confidence of inhibitory effect of colloidal silver nanoparticles, antibacterial effect of filter media coated with silver nanoparticles was evaluated via in vitro microbiology tests (zone of inhibition test and test tube test. Results: Present study showed that colloidal silver nanoparticles have good antimicrobial effects against tested bacteria, so that MIC and MBC of silver nanoparticles for Bacillus spp. were calculated 3.9 and 31.25 mg/L, respectively. Also significant decrease was observed in bacterial growth after exposure to filter media coated with silver nanoparticles in test tube test and  zone of inhibition test (P≤ 5%. Conclusion: The results of this research indicate that filter media coated with silver nanoparticles have considerable antimicrobial effects; therefore they could possibly be used as excellent antibacterial water filters and would have several applications in other sectors.

  12. Shape effect on the antibacterial activity of silver nanoparticles synthesized via a microwave-assisted method.

    Science.gov (United States)

    Hong, Xuesen; Wen, Junjie; Xiong, Xuhua; Hu, Yongyou

    2016-03-01

    Silver nanoparticles (AgNPs) are used as sustained-release bactericidal agents for water treatment. Among the physicochemical characteristics of AgNPs, shape is an important parameter relevant to the antibacterial activity. Three typically shaped AgNPs, nanocubes, nanospheres, and nanowires, were prepared via a microwave-assisted method and characterized by TEM, UV-vis, and XRD. The antibacterial activity of AgNPs was determined by OD growth curves tests, MIC tests, and cell viability assay against Escherichia coli. The interaction between AgNPs and bacterial cells was observed by TEM. The results showed that the three differently shaped AgNPs were nanoscale, 55 ± 10 nm in edge length for nanocubes, 60 ± 15 nm in diameter for nanospheres, 60 ± 10 nm in diameter and 2-4 μm in length for nanowires. At the bacterial concentration of 10(4) CFU/mL, the MIC of nanocubes, nanospheres, and nanowires were 37.5, 75, and 100 μg/mL, respectively. Due to the worst contact with bacteria, silver nanowires exhibited the weakest antibacterial activity compared with silver nanocubes and silver nanospheres. Besides, silver nanocubes mainly covered by {100} facets showed stronger antibacterial activity than silver nanospheres covered by {111} facets. It suggests that the shape effect on the antibacterial activity of AgNPs is attributed to the specific surface areas and facets reactivity; AgNPs with larger effective contact areas and higher reactive facets exhibit stronger antibacterial activity.

  13. Enhanced antibacterial effect of antibiotics in combination with silver nanoparticles against animal pathogens.

    Science.gov (United States)

    Smekalova, Monika; Aragon, Virginia; Panacek, Ales; Prucek, Robert; Zboril, Radek; Kvitek, Libor

    2016-03-01

    Antibiotic resistant bacteria are a serious health risk in both human and veterinary medicine. Several studies have shown that silver nanoparticles (AgNPs) exert a high level of antibacterial activity against antibiotic resistant strains in humans. The aim of this study was to evaluate the antibacterial effects of a combined therapy of AgNPs and antibiotics against veterinary bacteria that show resistance to antibiotics. A microdilution checkerboard method was used to determine the minimal inhibitory concentrations of both types of antimicrobials, alone and in combination. The fractional inhibitory concentration index was calculated and used to classify observed collective antibacterial activity as synergistic, additive (only the sum of separate effects of drugs), indifferent (no effect) or antagonistic. From the 40 performed tests, seven were synergistic, 17 additive and 16 indifferent. None of the tested combinations showed an antagonistic effect. The majority of synergistic effects were observed for combinations of AgNPs given together with gentamicin, but the highest enhancement of antibacterial activity was found with combined therapy together with penicillin G against Actinobacillus pleuropneumoniae. A. pleuropneumoniae and Pasteurella multocida originally resistant to amoxycillin, gentamicin and colistin were sensitive to these antibiotics when combined with AgNPs. The study shows that AgNPs have potential as adjuvants for the treatment of animal bacterial diseases.

  14. Nature's combinatorial biosynthesis and recently engineered production of nucleoside antibiotics in Streptomyces.

    Science.gov (United States)

    Chen, Shawn; Kinney, William A; Van Lanen, Steven

    2017-04-01

    Modified nucleosides produced by Streptomyces and related actinomycetes are widely used in agriculture and medicine as antibacterial, antifungal, anticancer and antiviral agents. These specialized small-molecule metabolites are biosynthesized by complex enzymatic machineries encoded within gene clusters in the genome. The past decade has witnessed a burst of reports defining the key metabolic processes involved in the biosynthesis of several distinct families of nucleoside antibiotics. Furthermore, genome sequencing of various Streptomyces species has dramatically increased over recent years. Potential biosynthetic gene clusters for novel nucleoside antibiotics are now apparent by analysis of these genomes. Here we revisit strategies for production improvement of nucleoside antibiotics that have defined mechanisms of action, and are in clinical or agricultural use. We summarize the progress for genetically manipulating biosynthetic pathways for structural diversification of nucleoside antibiotics. Microorganism-based biosynthetic examples are provided and organized under genetic principles and metabolic engineering guidelines. We show perspectives on the future of combinatorial biosynthesis, and present a working model for discovery of novel nucleoside natural products in Streptomyces.

  15. Effects of Extended Exposure to the Antibacterial Triclosan in the the Adult Female Rat

    Science.gov (United States)

    Triclosan (TCS), an antibacterial, has been shown to have endocrine disrupting activity in the rat. We reported previously that TCS advanced puberty in the female rat in the female pubertal assay and potentiated the estrogenic effect of ethinyl estradiol (EE) on uterine growth i...

  16. The effect of antibacterial and non-antibacterial compounds alone or associated with antifugals upon fungi

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    Maria Manuel eAzevedo

    2015-07-01

    Full Text Available During the last 30 years the incidence of fungal infections has increased dramatically. While the antifungal therapeutic options available are somewhat reduced, most pathogenic microorganisms have an incredible capacity to mutate and acquire resistance. In addition, multiple drugs are often required concomitantly to manage clinically complex disorders. The combination of antibiotics or other compounds with antifungal drugs, simultaneously or sequentially, is commonly adopted in clinical practice, although without a full knowledge of the consequences. Thus, the role of combined therapy and the effect of antibiotics upon fungal growth promotion needs to be critically evaluated and understood in order to avoid undesirable drug interactions. With this review we intend discuss the studies that report about antibiotics inhibiting fungal growth, as well as studies describing the synergistic effect of the combined therapy, i.e. associations between antibiotics or other compounds with antifungal drugs. Alternative therapeutic protocols for fungal disease could be designed, taking advantage of such drug combinations. Critical revision of previously published data is crucial in order to define future research strategies.

  17. Intratubular Antibacterial Effect of Polyethyleneimine Nanoparticles: An Ex Vivo Study in Human Teeth

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    Itzhak Abramovitz

    2015-01-01

    Full Text Available Enterococcus faecalis is a facultative gram positive bacterium which can remain in the teeth root canals and cause refractory or persistent periapical diseases. E. faecalis bacteria that penetrate the dentinal tubules can be the source of intracanal infection and endodontic disease. Quaternary ammonium polyethyleneimine (QPEI nanopolymers were shown to have long lasting antibacterial activity against gram positive and gram negative bacteria. The present study evaluated the intratubular antibacterial effect of an epoxy resin sealer incorporating 1% QPEI against E. faecalis in a human dentin model. Root canals of extracted teeth were inoculated with E. faecalis for 7 days prior to standard endodontic treatment. The antibacterial effect of an epoxy-amine resin endodontic sealer was tested at concentration of 0% or 1% (wt/wt added QPEI nanoparticles. Reduction in bacterial viability p<0.01 was depicted in the dentinal tubules of the root canals obturated with the sealer incorporating QPEI nanoparticles. In conclusion, QPEI nanoparticles when incorporated in a small percentage into epoxy-resin based sealer may target E. faecalis in the dentinal tubules, producing a potent antibacterial effect that reduces significantly bacterial viability.

  18. Detection of antibacterial substances in some plant residues and their effect on certain micro-organisms.

    Science.gov (United States)

    Abdel-Nasser, M; Safwat, M S; Ali, M Z

    1983-01-01

    The effect of dry residues from several plants, belonging to different families on certain microorganisms in vitro and in vivo, was studied. Dry residues of paprica leaves, tomato tops, egg plant leaves, guava leaves, onion peels, garlic tops, wheat straw, sugar cane leaves, cotton leaves, Egyptian clover tops, field bean tops or pea tops were examined for the presence of antibacterial substances, using successive extractions with hexane, ethyl ether, ethanol, and water, respectively, for each plant residue. On culture media, the antibacterial effect, expressed as width of inhibition zones, differed according to the type of plant, type of micro-organism, and extraction medium, used for each plant. Water extract from each of the studied plants showed no effect on any of the studied micro-organisms, while the other extracts indicated the presence of antibacterial substances in all the used plants. In most cases, ether extract showed the highest incidence of antimicrobial activities against the majority of test micro-organisms. In general, the antibacterial substances seemed to be more inhibitory to Gram-positive bacteria than to Gram-negative ones. Ethyl-ether extract of the residues of most of these plants markedly affected the growth of more than one of the different Rhizobium species when grown on culture medium, as indicated by the presence of wide zones of inhibition.

  19. Elution of monomers from three different bonding systems and their antibacterial effect.

    Science.gov (United States)

    Polydorou, Olga; Rogatti, Philipp; Bolek, Richard; Wolkewitz, Martin; Kümmerer, Klaus; Hellwig, Elmar

    2013-07-01

    The aim of the present study was to evaluate the release of monomers from three bonding systems and to correlate it with their antibacterial effect. Three bonding systems (Optibond FL(®), Xeno III(®) and Clearfil™ Protect Bond) were tested after storage in ethanol 75 % and human saliva. Twenty samples (n = 10/medium) of each bonding material were prepared and polymerized according to the manufacturers' instructions. Each sample was stored in 1 ml of the respective storage medium. The medium was renewed after 24 h, 7 days, and 28 days and was analysed by LC-MS/MS for the release of substances. Additionally, the antibacterial effect of the unpolymerized components of each bonding system and their polymerized mixture was tested using agar disc-diffusion test with Streptococcus mutans. Only HEMA was found to be released. The amount of HEMA detected in the ethanol samples was significantly higher compared to the saliva samples (p Optibond FL(®) < Xeno III(®.) According to the agar disc-diffusion test, all materials exhibited certain antibacterial activity. The release of HEMA from all tested materials even after storing in human saliva increases the concerns about their toxicity. Their antibacterial effect seems not be due to the release of substances.

  20. Antibacterial Effects of Pyrolysis Oil Against Salmonella Typhimurium and Escherichia coli.

    Science.gov (United States)

    Patra, Jayanta Kumar; Das, Gitishree; Choi, Joon Weon; Baek, Kwang-Hyun

    2016-01-01

    Many issues have been found to be related to food preservation and food contamination caused by various pathogenic bacteria in recent years. Many antibacterial agents act efficiently against Gram-positive foodborne bacteria; however, they are less effective against Gram-negative foodborne bacteria. In the present study, an attempt has been made to evaluate the antibacterial activity of pyrolysis oil manufactured from Pinus densiflora (PLO) against two Gram-negative foodborne pathogenic bacteria, Salmonella Typhimurium and Escherichia coli O157:H7. PLO possessed potent antibacterial activity against both foodborne pathogenic bacteria, as indicated by inhibition zones of 10.33-12.33 mm and minimum inhibitory concentration and minimum bactericidal concentration values of 250-500 μg/mL and 500-1000 μg/mL, respectively. PLO at the minimum inhibitory concentration exhibited an inhibitory effect on the viability of the bacterial pathogens with leakage of 260 nm absorbing materials, an increase in the relative electrical conductivity, and loss of salt tolerance capacity. PLO exhibited promising antibacterial activity against both of the Gram-negative foodborne pathogenic bacteria and thus it can be utilized in the food sector and pharmaceutical industries for the development of antibiotics and preservatives.

  1. The Investigation of Antibacterial Effects of Salvia Sahendica Extracts on Some Pathogenic Bacteria

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    H Bannazadeh Baghi

    2007-06-01

    Full Text Available Background: The salvia plant is one of the Lamiacea family members, that is being cultiurated all over the world. In Iran almost all spices of this plant could found, that are used for medical, food industry and parfumers production. Salvia sahendica genus is the member of this family, that its antibacterial effects on Klebsiella pneumonia, Staphylococcus aureus and Pseudomonas aeruginosa have been investigated. Methods: In this study are used standard strains of Pseudomonas aeruginosa (ATCC 27852 Staphylococcus aureus, (ATCC 25923 and, Klebsiella pneumonia (ATCC 3583. Salvia was provided from Tabriz mall and was powdered. Then this powder was suspended with ratio 1:10 with Metanol, Aceton, Chloroform, Hexan, Ethyl acetate and water. After 24h extractions isolated and concentrated with distillated in vacuum system. Which of bacteria were cultured to over night in Mohler Hinton agar medium, then compared with 0.5 macfarland. In continue extraction were tested by used of well assay method and then the diameter of zone measured. Experiments repeated tree times and the average of data obtained. In each of tests we had a control from special solvent. Results: Regarding to the results, all of salvia sahendica extractions showed antibacterial activity on Staphylococcus aureus, Pseudomonas aeruginosa and. That regarding Klebsiella pneumonia, Ethanol, Chloroform, Ethyl acetate, Hexan, and regarding Staphylococcus aureus Metanol, Aceton, Chloroform, Hexan, Ethyl acetate and Pseudomonas aeruginosa only Chloroform this plant has antibacterial effects. Chloroform extraction of salvia shows the most antibacterial activity (with the biggest diameter of antibacterial zone. Conclusion: Regarding the carried out study it could be noted that for inhibition and destroying Staphylococcus aureus and Klebsiella pneumonia, plants effects extraction could be used.

  2. Effect of vegetation cycle on chemical content and antibacterial activity of Satureja montana L.

    Directory of Open Access Journals (Sweden)

    Damjanović-Vratnica Biljana

    2011-01-01

    Full Text Available Effect of vegetation cycle on phytochemical composition of the essential oil obtained from the aerial parts of wild-growing winter savory (Satureja montana L. from Montenegro was analysed by GC-MS and its antibacterial activity tested at different oil concentrations. A total of 36 and 34 constituents were identified in the hydrodistilled oil obtained from herb before flowering and during flowering stage, with major components: thymol (37,36% and 27,68%, carvacrol (15,47% and 4,40%, γ-terpinene (11,75% and 8.66% and p-cymene (7,86% and 31, 37%, respectively. The gained results revealed that essential oil of S. montana has rather significant antibacterial activity against chosen bacteria Staphylococcus aureus, Escherichia coli and Bacillus subtilis. Also, it was found that vegetation cycle affects the chemical composition and antibacterial activity of savory essential oil. Essential oil gained prior to herb flowering period showed stronger antibacterial activity in comparison with the oil gained during herb flowering.

  3. Antibacterial Effects and Biocompatibility of Titania Nanotubes with Octenidine Dihydrochloride/Poly(lactic-co-glycolic acid)

    Science.gov (United States)

    Xu, Zhiqiang; Lai, Yingzhen; Wu, Dong; Huang, Wenxiu; Huang, Sijia; Zhou, Lin; Chen, Jiang

    2015-01-01

    Titanium (Ti) implants with long-term antibacterial ability and good biocompatibility are highly desirable materials that can be used to prevent implant-associated infections. In this study, titania nanotubes (TNTs) were synthesized on Ti surfaces through electrochemical anodization. Octenidine dihydrochloride (OCT)/poly(lactic-co-glycolic acid) (PLGA) was infiltrated into TNTs using a simple solvent-casting technique. OCT/PLGA-TNTs demonstrated sustained drug release and maintained the characteristic hollow structures of TNTs. TNTs (200 nm in diameter) alone exhibited slight antibacterial effect and good osteogenic activity but also evidently impaired adhesion and proliferation of bone marrow mesenchymal stem cells (BMSCs). OCT/PLGA-TNTs (100 nm in diameter) supported BMSC adhesion and proliferation and showed good osteogenesis-inducing ability. OCT/PLGA-TNTs also exhibited good long-term antibacterial ability within the observation period of 7 d. The synthesized drug carrier with relatively long-term antibacterial ability and enhanced excellent biocompatibility demonstrated significant potential in bone implant applications. PMID:26090449

  4. Preparation, antibacterial effects and corrosion resistant of porous Cu–TiO{sub 2} coatings

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Haibo; Zhang, Xiangyu, E-mail: zhangxiangyu@tyut.edu.cn; Geng, Zhenhua; Yin, Yan; Hang, Ruiqiang; Huang, Xiaobo; Yao, Xiaohong; Tang, Bin

    2014-07-01

    Antibacterial TiO{sub 2} coatings with different concentrations of Cu (Cu–TiO{sub 2}) were prepared by micro-arc oxidation (MAO) on pre-sputtered CuTi films. The effect of Cu concentrations in CuTi films on the MAO process was investigated. The Cu–TiO{sub 2} coatings were analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The corrosion resistance of Cu–TiO{sub 2} coatings was evaluated via potentiodynamic polarization method. The antibacterial properties were assessed by two methods: spread plate method and fluorescence staining. The experimental results demonstrate that the coatings are porous and consist of anatase phase, rutile phase and unoxidized titanium. The CuTi films are almost completely oxidized and the thickness of all MAO coatings is about 5–10 μm. Cu mainly exists as CuO in the TiO{sub 2} coatings. The Cu–TiO{sub 2} coatings exhibit excellent antibacterial activities, and the antibacterial rate gradually rise with the increase in Cu concentration in the MAO coatings. The corrosion resistance of MAO coatings is also improved slightly.

  5. Antioxidant, antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract

    Science.gov (United States)

    Rahman, Md Atiar; Islam, Md Saiful

    2013-01-01

    Objective To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucas aspera (Labiatae) (L. aspera) alcoholic extract. Methods Whole L. aspera powder was extracted by absolute ethanol (99.50%). The ethanolic extract was subjected to antioxidant, antibacterial and brine shrimp lethality assay. Results The extract showed potent radical scavenging effect (antioxidant) with IC50 value of (99.58±1.22) µg/mL which was significant (P<0.01) in comparison to ascorbic acid with IC50 value of (1.25±0.95) µg/mL. In case of antibacterial screening, the extract showed notable antibacterial effect against the tested microbial strains. Significant (P<0.05) zone of inhibitions against Gram positive Bacillus subtilis [(12.00±1.32) mm] and Bacillus megaterium [(13.00±1.50) mm], Staphylococcus aureus [(8.00±0.50) mm] and Gram negative Salmonella typhi [(6.00±0.50) mm], Salmonella paratyphi [(8.00±1.00) mm], Shigella dysenteriae [(9.00±1.32) mm] and Vibrio cholerae [(9.00±0.66) mm] was observed. In brine shrimp lethality bioassay, the extract showed the LC50 value as (181.68±2.15) µg/mL which was statistically significant (P<0.01) compared to positive control vincristine sulfate [LC50=(0.76±0.04) µg/mL]. Conclusions The results demonstrate that the ethanolic extract of L. aspera could be used as antibacterial, pesticidal and various pharmacologic actives. PMID:23620850

  6. Antioxidant, antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract

    Institute of Scientific and Technical Information of China (English)

    Md Atiar Rahman; Md Saiful Islam

    2013-01-01

    Objective: To investigate the antioxidant, antibacterial and cytotoxic activity of whole Leucasaspera (Labiatae) (L. aspera) alcoholic extract. Methods: Whole L. aspera powder was extracted by absolute ethanol (99.50%). The ethanolic extract was subjected to antioxidant, antibacterial and brine shrimp lethality assay. Results: The extract showed potent radical scavenging effect (antioxidant) with IC50 value of (99.58±1.22) µg/mL which was significant (P<0.01) in comparison to ascorbic acid with IC50 value of (1.25±0.95) µg/mL. In case of antibacterial screening, the extract showed notable antibacterial effect against the tested microbial strains. Significant (P<0.05) zone of inhibitions against Gram positive Bacillus subtilis [(12.00±1.32) mm] and Bacillus megaterium [(13.00±1.50) mm], Staphylococcus aureus [(8.00±0.50) mm] and Gram negative Salmonella typhi [(6.00±0.50) mm], Salmonella paratyphi [(8.00±1.00) mm], Shigella dysenteriae [(9.00±1.32) mm] and Vibrio cholerae [(9.00±0.66) mm] was observed. In brine shrimp lethality bioassay, the extract showed the LC50 value as (181.68±2.15) µg/mL which was statistically significant (P<0.01) compared to positive control vincristine sulfate [LC50=(0.76±0.04) µg/mL]. Conclusions: The results demonstrate that the ethanolic extract of L. aspera could be used as antibacterial, pesticidal and various pharmacologic actives.

  7. New insights into the synergism of nucleoside analogs with radiotherapy.

    Science.gov (United States)

    Lee, Michael W; Parker, William B; Xu, Bo

    2013-09-26

    Nucleoside analogs have been frequently used in combination with radiotherapy in the clinical setting, as it has long been understood that inhibition of DNA repair pathways is an important means by which many nucleoside analogs synergize. Recent advances in our understanding of the structure and function of deoxycytidine kinase (dCK), a critical enzyme required for the anti-tumor activity for many nucleoside analogs, have clarified the mechanistic role this kinase plays in chemo- and radio-sensitization. A heretofore unrecognized role of dCK in the DNA damage response and cell cycle machinery has helped explain the synergistic effect of these agents with radiotherapy. Since most currently employed nucleoside analogs are primarily activated by dCK, these findings lend fresh impetus to efforts focused on profiling and modulating dCK expression and activity in tumors. In this review we will briefly review the pharmacology and biochemistry of the major nucleoside analogs in clinical use that are activated by dCK. This will be followed by discussions of recent advances in our understanding of dCK activation via post-translational modifications in response to radiation and current strategies aimed at enhancing this activity in cancer cells.

  8. Antibacterial Activity and Synergistic Antibacterial Potential of Biosynthesized Silver Nanoparticles against Foodborne Pathogenic Bacteria along with its Anticandidal and Antioxidant Effects

    Science.gov (United States)

    Patra, Jayanta Kumar; Baek, Kwang-Hyun

    2017-01-01

    Silver nanoparticles plays a vital role in the development of new antimicrobial substances against a number of pathogenic microorganisms. These nanoparticles due to their smaller size could be very effective as they can improve the antibacterial activity through lysis of bacterial cell wall. Green synthesis of metal nanoparticles using various plants and plant products has recently been successfully accomplished. However, few studies have investigated the use of industrial waste materials in nanoparticle synthesis. In the present investigation, synthesis of silver nanoparticles (AgNPs) was attempted using the aqueous extract of corn leaf waste of Zea mays, which is a waste material from the corn industry. The synthesized AgNPs were evaluated for their antibacterial activity against foodborne pathogenic bacteria (Bacillus cereus ATCC 13061, Listeria monocytogenes ATCC 19115, Staphylococcus aureus ATCC 49444, Escherichia coli ATCC 43890, and Salmonella Typhimurium ATCC 43174) along with the study of its synergistic antibacterial activity. The anticandidal activity of AgNPs were evaluated against Candida species (C. albicans KACC 30003 and KACC 30062, C. glabrata KBNO6P00368, C. geochares KACC 30061, and C. saitoana KACC 41238), together with the antioxidant potential. The biosynthesized AgNPs were characterized by UV-Vis spectrophotometry with surface plasmon resonance at 450 nm followed by the analysis using scanning electron microscope, X-ray diffraction, Fourier-transform infrared spectroscopy and thermogravimetric analysis. The AgNPs displayed moderate antibacterial activity (9.26–11.57 mm inhibition zone) against all five foodborne pathogenic bacteria. When AgNPs were mixed with standard antibacterial or anticandidal agent, they displayed strong synergistic antibacterial (10.62–12.80 mm inhibition zones) and anticandidal activity (11.43–14.33 mm inhibition zones). In addition, the AgNPs exhibited strong antioxidant potential. The overall results

  9. Effectiveness of Extracted Antibacterial Compound From Hydroid Aglaophenia Cupressina Lamoureoux Against Bacterial Cell of Escherichia Coli

    OpenAIRE

    2013-01-01

    Pollution by pathogenic microorganisms in food materials is capable of resulting in various diseases and increased resistance against various types of antimicrobial. Therefore, new more effective antibiotics are needed to overcome the multi-drug resistant bacteria. This study was aimed to examine the effectiveness of extracted antibacterial compound from hydroid Aglaophenia cupressina Lamoureoux in inhibiting and killing the Eschrichia Coli, an organism that frequently pollute food material. ...

  10. NEW THERAPEUTIC FORMULATIONS WITH AN ANTIBACTERIAL EFFECT, BASED ON PLANT EXTRACTS

    OpenAIRE

    Liliana Cristina Soare; Ionica Deliu; Ion Iosub; Codruţa-Mihaela Dobrescu; Mariana Ferdeş

    2012-01-01

    The antibacterial effects produced by anthocyanins and other bioactive plant compounds are weaker than those generated by antibiotics. In some cases, the combination of extract-antibiotic can cause synergistic effects, also the purpose of the research was to develop and test new antibiotic - plant extract formulations. New potential antimicrobial formulations was done by soaking discs impregnated with piperacillin or tetracycline with different extract. The tested microorganisms were: Staphyl...

  11. Antibacterial Effect of Autologous Platelet-Rich Gel Derived from Subjects with Diabetic Dermal Ulcers In Vitro

    OpenAIRE

    Lihong Chen; Chun Wang; Hengchuan Liu; Guanjian Liu; Xingwu Ran

    2013-01-01

    Background. Autologous platelet-rich gel (APG) is an effective method to improve ulcer healing. However, the mechanisms are not clear. This study aimed to investigate the antibacterial effect of APG in vitro. Methods. Platelet-rich plasma (PRP), platelet-poor plasma (PPP) and APG were prepared from whole blood of sixteen diabetic patients with dermal ulcers. Antibacterial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were evaluated by bacteriostasis assay...

  12. NEW THERAPEUTIC FORMULATIONS WITH AN ANTIBACTERIAL EFFECT, BASED ON PLANT EXTRACTS

    Directory of Open Access Journals (Sweden)

    Liliana Cristina Soare

    2012-12-01

    Full Text Available The antibacterial effects produced by anthocyanins and other bioactive plant compounds are weaker than those generated by antibiotics. In some cases, the combination of extract-antibiotic can cause synergistic effects, also the purpose of the research was to develop and test new antibiotic - plant extract formulations. New potential antimicrobial formulations was done by soaking discs impregnated with piperacillin or tetracycline with different extract. The tested microorganisms were: Staphylococcus aureus ATCC 25923, Streptococcus sp., Escherichia coli 820B, soil bacterium 23S, and Enterobacter cloacae. The combination of antibiotics with extracts determined, only for some of the microorganisms tested, better antibacterial effects than those caused by the antibiotic or the extract.

  13. The synthesis of double-headed nucleosides by the CuAAC reaction and their effect in secondary nucleic acid structures

    DEFF Research Database (Denmark)

    Jørgensen, Anna Søndergaard; Shaikh, Khalil Isak; Enderlin, Gerald;

    2011-01-01

    Four double-headed nucleosides were prepared by the CuAAC reaction. Hereby, a triazole-containing linker connects an additional thymine or adenine to the 2´-position of 2´-deoxyuridine, a thymine to the 5´-position of thymidine and a thymine to the 6¢-position of an LNA-thymidine monomer. Whereas...

  14. Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

    Directory of Open Access Journals (Sweden)

    Ponmurugan Karuppiah

    2012-08-01

    Conclusions: Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.

  15. Antibacterial effect of various shapes of silver nanoparticles monitored by SERS.

    Science.gov (United States)

    El-Zahry, Marwa R; Mahmoud, Amer; Refaat, Ibrahim H; Mohamed, Horria A; Bohlmann, Holger; Lendl, Bernhard

    2015-06-01

    A comparative evaluation of antimicrobial effect of synthesized silver nanoparticles (AgNPs) of different shapes using different methods was performed. Spherical, triangular and hexagonal AgNPs with an average size of 40 nm were chemically prepared and characterized by transmission electron microscope (TEM) and UV-visible spectroscopy. The antimicrobial effect of these different AgNPs against the gram negative bacterium Escherichia coli (E. coli) was studied by surface enhanced Raman spectroscopy (SERS), the evaluation of growth curves and inhibition zones. SERS proved to be sensitive to monitor the changes that occurred in the bacterial cells upon interaction with AgNPs, which qualitatively compared well with the data provided by the reference methods. However, as SERS is already sensitive to initial changes in the chemistry of bacteria due to the antibacterial effect of the AgNPs, fast and detailed information is provided by SERS as opposed to the classical reference methods based on the evaluation of growth curves and inhibition zones. The results of this work also demonstrate that hexagonal AgNPs display the highest antibacterial effect when compared to other NPs shapes, with triangular AgNPs exhibiting no antibacterial effect under the adopted conditions.

  16. Biocompatibility and antibacterial effect of silver doped 3D-glass-ceramic scaffolds for bone grafting.

    Science.gov (United States)

    Balagna, Cristina; Vitale-Brovarone, Chiara; Miola, Marta; Verné, Enrica; Canuto, Rosa Angela; Saracino, Silvia; Muzio, Giuliana; Fucale, Giacomo; Maina, Giovanni

    2011-02-01

    A 3D-glass-ceramic scaffold for bone tissue engineering with an interconnected macroporous network of pores was doped with silver ions in order to confer antibacterial properties. For this purpose, silver ions were selectively added to the scaffold surfaces through ion-exchange using an aqueous silver nitrate solution. The silver-doped scaffolds were characterized by means of leaching, in vitro antibacterial, and citotoxicity tests. In particular, the silver effect was examined through a broth dilution test in order to evaluate the proliferation of bacteria by counting the colonies forming units. Moreover, cytotoxicity tests were carried out to understand the effect of silver-containing scaffolds on cell adhesion, proliferation, and vitality. For all tests a comparison between silver-doped scaffold and silver-doped scaffold dry sterilized was performed.

  17. Antibacterial Effect of Granati fructus Cortex Extract on Streptococcus mutans In Vitro

    Directory of Open Access Journals (Sweden)

    Cut R. Alfath

    2013-07-01

    Full Text Available 72 1024x768 The rind of pomegranate fruit (Granati fructus cortex composed of antibacterial compounds such as alkaloid, flavonoid and tannin. Objective: To evaluate the bacterial effect of Granati fructus cortex extract against Streptococcus mutans. Methods: The study was laboratory experimental. The inhibition test was performed by agar diffusion method on MHA medium. Results: It showed the bacterial property of Granati fructus cortex on various concentration. The highest extract concentration of 30% extract has the largest of inhibition zones (15.4mm. The results showed a difference in the size of inhibition zones related to different extract concentrations. Conclusion: This study confirmed the antibacterial effect of Granati fructus cortex on the growth of Streptococcus mutans.DOI: 10.14693/jdi.v20i1.126

  18. In Vitro Antibacterial and Antibiotic Resistance Modifying Effect of Bioactive Plant Extracts on Methicillin-Resistant Staphylococcus epidermidis

    OpenAIRE

    Romana Chovanová; Mária Mikulášová; Štefánia Vaverková

    2013-01-01

    The crude extracts of plants from Asteraceae and Lamiaceae family and essential oils from Salvia officinalis and Salvia sclarea were studied for their antibacterial as well as antibiotic resistance modifying activity. Using disc diffusion and broth microdilution assays we determined higher antibacterial effect of three Salvia spp. and by evaluating the leakage of 260 nm absorbing material we detected effect of extracts and, namely, of essential oils on the disruption of cytoplasmic membrane. ...

  19. [Antibacterial effects of water-soluble low-molecular-weight chitosans on different microorganisms].

    Science.gov (United States)

    Gerasimenko, D V; Avdienko, I D; Bannikova, G E; Zueva, O Iu; Varlamov, V P

    2004-01-01

    Low-molecular-weight chitosans with a viscosity-average molecular weight (Mv) of 5 to 27 kDa and equal degree of deacetylation (DD, 85%) were highly active against Pseudomonas aureofaciens, Enterobacter agglomerans, Bacillus subtilis, and Bifidobacterium bifidum 791, causing death of 80 to 100% of cells. An exception to this tendency was Escherichia coli, for which the rate of cell death, induced by the 5-kDa chitosan, was 38%. The antibacterial effect was manifested as early as 10 min after incubation of 12-kDa chitosan with B. subtilis or E. coli cells. Candida krusei was almost insensitive to the above crab chitosans. However, Candida krusei was highly sensitive to chitosans with Mv 5, 6, 12, 15.7, and 27 kDa: the minimum inhibitory concentration (MIC) varied from 0.06 to 0.005%. Chitosans with M, 5, 12, and 15.7 kDa exerted an antibacterial effect on Staphylococcus aureus. Chitosans with Mv 5, 15.7, and 27 kDa had no effect on Bifidobacterium bifidum ATCC 14893. The antibacterial effect of the 4-kDa chitosan on E. coli and B. bifidum 791 increased with DD in the range 55-85%.

  20. Susceptibility of Porphyromonas gingivalis and Streptococcus mutans to Antibacterial Effect from Mammea americana

    Directory of Open Access Journals (Sweden)

    Alejandra Herrera Herrera

    2014-01-01

    Full Text Available The development of periodontal disease and dental caries is influenced by several factors, such as microorganisms of bacterial biofilm or commensal bacteria in the mouth. These microorganisms trigger inflammatory and immune responses in the host. Currently, medicinal plants are treatment options for these oral diseases. Mammea americana extracts have reported antimicrobial effects against several microorganisms. Nevertheless, this effect is unknown against oral bacteria. Therefore, the aim of this study was to evaluate the antibacterial effect of M. americana extract against Porphyromonas gingivalis and Streptococcus mutans. For this, an experimental study was conducted. Ethanolic extract was obtained from seeds of M. americana (one oil phase and one ethanolic phase. The strains of Porphyromonas gingivalis ATCC 33277 and Streptococcus mutans ATCC 25175 were exposed to this extract to evaluate its antibacterial effect. Antibacterial activity was observed with the two phases of M. americana extract on P. gingivalis and S. mutans with lower MICs (minimum inhibitory concentration. Also, bactericidal and bacteriostatic activity was detected against S. mutans, depending on the concentration of the extract, while on M. americana extract presented only bacteriostatic activity against P. gingivalis. These findings provide important and promising information allowing for further exploration in the future.

  1. Photocatalytic antibacterial effects are maintained on resin-based TiO2 nanocomposites after cessation of UV irradiation.

    Directory of Open Access Journals (Sweden)

    Yanling Cai

    Full Text Available Photocatalysis induced by TiO2 and UV light constitutes a decontamination and antibacterial strategy utilized in many applications including self-cleaning environmental surfaces, water and air treatment. The present work reveals that antibacterial effects induced by photocatalysis can be maintained even after the cessation of UV irradiation. We show that resin-based composites containing 20% TiO2 nanoparticles continue to provide a pronounced antibacterial effect against the pathogens Escherichia coli, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus mutans and Enterococcus faecalis for up to two hours post UV. For biomaterials or implant coatings, where direct UV illumination is not feasible, a prolonged antibacterial effect after the cessation of the illumination would offer new unexplored treatment possibilities.

  2. Screening and characterization of purine nucleoside degrading lactic acid bacteria isolated from Chinese sauerkraut and evaluation of the serum uric acid lowering effect in hyperuricemic rats.

    Directory of Open Access Journals (Sweden)

    Ming Li

    Full Text Available Hyperuricemia is well known as the cause of gout. In recent years, it has also been recognized as a risk factor for arteriosclerosis, cerebrovascular and cardiovascular diseases, and nephropathy in diabetic patients. Foods high in purine compounds are more potent in exacerbating hyperuricemia. Therefore, the development of probiotics that efficiently degrade purine compounds is a promising potential therapy for the prevention of hyperuricemia. In this study, fifty-five lactic acid bacteria isolated from Chinese sauerkraut were evaluated for the ability to degrade inosine and guanosine, the two key intermediates in purine metabolism. After a preliminary screening based on HPLC, three candidate strains with the highest nucleoside degrading rates were selected for further characterization. The tested biological characteristics of candidate strains included acid tolerance, bile tolerance, anti-pathogenic bacteria activity, cell adhesion ability, resistance to antibiotics and the ability to produce hydrogen peroxide. Among the selected strains, DM9218 showed the best probiotic potential compared with other strains despite its poor bile resistance. Analysis of 16S rRNA sequences showed that DM9218 has the highest similarity (99% to Lactobacillus plantarum WCFS1. The acclimated strain DM9218-A showed better resistance to 0.3% bile salt, and its survival in gastrointestinal tract of rats was proven by PCR-DGGE. Furthermore, the effects of DM9218-A in a hyperuricemia rat model were evaluated. The level of serum uric acid in hyperuricemic rat can be efficiently reduced by the intragastric administration of DM9218-A (P<0.05. The preventive treatment of DM9218-A caused a greater reduction in serum uric acid concentration in hyperuricemic rats than the later treatment (P<0.05. Our results suggest that DM9218-A may be a promising candidate as an adjunctive treatment in patients with hyperuricemia during the onset period of disease. DM9218-A also has potential

  3. XML Investigating the Phytochemical, Antibacterial and Antifungal Effects of Thymus Vulgaris and Cuminum Cyminum Essential Oils

    OpenAIRE

    2016-01-01

    Background and Objective: The aim of this study was to determine the chemical composition, antibacterial and antifungal effects of Thymus vulgaris and Cuminum Cyminum essential oils against foodborne pathogens and Candida species in vitro. Methods: The essential oils were extracted from the aerial parts of Thymus vulgaris and dried Cuminum Cyminum seeds using a Clevenger apparatus for 3 hours. Analysis of the essential oils’ constituents was performed using gas chromatography-mass s...

  4. The Investigation of Antibacterial Effects of Salvia Sahendica Extracts on Some Pathogenic Bacteria

    OpenAIRE

    H Bannazadeh Baghi

    2007-01-01

    Background: The salvia plant is one of the Lamiacea family members, that is being cultiurated all over the world. In Iran almost all spices of this plant could found, that are used for medical, food industry and parfumers production. Salvia sahendica genus is the member of this family, that its antibacterial effects on Klebsiella pneumonia, Staphylococcus aureus and Pseudomonas aeruginosa have been investigated. Methods: In this study are used standard strains of Pseudomonas aeruginosa (ATCC ...

  5. The effect of Ultrafine process on the Dissolution, Antibacterial activity, and Cytotoxicity of Coptidis rhizoma

    Directory of Open Access Journals (Sweden)

    Zhen-Yu Jiang

    2016-01-01

    Full Text Available Background: The dosage of herb ultrafine particle (UFP depended on the increased level of its dissolution, toxicity, and efficacy. Objective: The dissolution, antibacterial activity, and cytotoxicity of Coptidis rhizoma (CR UFP were compared with those of traditional decoction (TD. Materials and Methods: The dissolution of berberine (BBR of CR TD and UFP was determined by high-performance liquid chromatography. The antibacterial activity of CR extract was assayed by plate-hole diffusion and broth dilution method; the inhibitory effect of rat serums against bacteria growth was evaluated after orally given CR UFP or TD extract. The cytotoxicity of CR extract was evaluated by 3-(4,5-dimethylthiazol-2-Yl-2,5-diphenyltetrazolium bromide assay. Results: The dissolution amount of BBR from CR UFP increased 6-8-folds in comparison to TD at 2 min, the accumulative amount of BBR in both UFP and TD group increased in a time-dependent manner. The minimal inhibitory concentrations and minimal bactericidal concentrations of CR UFP extract decreased to 1/2~1/4 of those of TD extract. The inhibitory effect of rat serums against bacteria growth decreased time-dependently, and no statistical difference was observed between two groups at each time point. The 50% cytotoxic concentrations of UFP extract increased 1.66~1.97 fold than those of TD. Conclusions: The antibacterial activity and cytotoxicity of CR UFP increased in a dissolution-effect manner in vitro, the increased level of cytotoxicity was lower than that of antibacterial activity, and the inhibitory effect of rat serums containing drugs of UFP group did not improve.

  6. Antibacterial properties of tualang honey and its effect in burn wound management: a comparative study

    Directory of Open Access Journals (Sweden)

    Nasir Nur-Azida

    2010-06-01

    Full Text Available Abstract Background The use of honey as a natural product of Apis spp. for burn treatment has been widely applied for centuries. Tualang honey has been reported to have antibacterial properties against various microorganisms, including those from burn-related diagnoses, and is cheaper and easier to be absorbed by Aquacel dressing. The aim of this study is to evaluate the potential antibacterial properties of tualang honey dressing and to determine its effectiveness as a partial thickness burn wound dressing. Methods In order to quantitate the bioburden of the swabs, pour plates were performed to obtain the colony count (CFU/ml. Swabs obtained from burn wounds were streaked on blood agar and MacConkey agar for bacterial isolation and identification. Later, antibacterial activity of Aquacel-tualang honey, Aquacel-Manuka honey, Aquacel-Ag and Aquacel- plain dressings against bacteria isolated from patients were tested (in-vitro to see the effectiveness of those dressings by zone of inhibition assays. Results Seven organisms were isolated. Four types of Gram-negative bacteria, namely Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas spp. and Acinetobacter spp., and three Gram-positive bacteria, namely Staphylococcus aureus, coagulase-negative Staphylococcus aureus (CONS and Streptococcus spp., were isolated. Total bacterial count decreased on day 6 and onwards. In the in-vitro antibacterial study, Aquacel-Ag and Aquacel-Manuka honey dressings gave better zone of inhibition for Gram positive bacteria compared to Aquacel-Tualang honey dressing. However, comparable results were obtained against Gram negative bacteria tested with Aquacel-Manuka honey and Aquacel-Tualang honey dressing. Conclusions Tualang honey has a bactericidal as well as bacteriostatic effect. It is useful as a dressing, as it is easier to apply and is less sticky compared to Manuka honey. However, for Gram positive bacteria, tualang honey is not as effective as usual care

  7. Atomic force microscopy study of the antibacterial effects of chitosans on Escherichia coli and Staphylococcus aureus

    OpenAIRE

    2008-01-01

    Chitosan has been reported to be a non-toxic, biodegradable antibacterial agent. The aim of this work was to elucidate the relationship between the molecular weight of chitosan and its antimicrobial activity upon two model microorganisms, one Gram-positive (Staphylococcus aureus) and one Gramnegative (Escherichia coli). Atomic force microscopy (AFM) imaging was used to obtain high-resolution images of the effect of chitosans on the bacterial morphology. The AFM measurements were correlated...

  8. Effects of quaternization on the morphological stability and antibacterial activity of electrospun poly(DMAEMA-co-AMA) nanofibers.

    Science.gov (United States)

    Xu, Jing-Wei; Wang, Yao; Yang, Yun-Feng; Ye, Xiang-Yu; Yao, Ke; Ji, Jian; Xu, Zhi-Kang

    2015-09-01

    Electrospun nanofibers with antibacterial activity are greatly promising for medical treatment and water purification. Herein we report antibacterial nanofibers electrospun from a series of poly(dimethylamino ethyl methacrylate-co-alkyl methacrylates) (poly(DMAEMA-co-AMA)) and to distinguish the effects of free and cross-linked cations derived from quanternization on the antibacterial activity. Poly(DMAEMA-co-AMA)s are simply synthesized by free radical polymerization from commercial monomers. DSC analysis indicates that they have Tg lower than room temperature and thus the electrospun nanofibers adhere to each other and evenly tend to form films, instead of keeping cylinderic shape. Benzyl chloride (BC) and p-xylylene dichloride (XDC) can quaternize DMAEMA units and to generate cations on the nanofiber surface. XPS analysis and colorimetric assay determine the quaternization degree and the surface accessible quaternary amines (N(+)), respectively. It is very promising that this quaternization endows the electrospun nanofibers with both stable morphology and antibacterial activity. The BC-quaternized fibers show better antibacterial behavior against Escherichia coli and Staphylococcus aureus than those of the XDC-quaternized/cross-linked ones, because cross-linking suppresses the chain mobility of cations. Our results confirm that antibacterial nanofibers can be facilely prepared and chain mobility of the formed cations is the necessary prerequisite for their antibacterial activity.

  9. Strong and Nonspecific Synergistic Antibacterial Efficiency of Antibiotics Combined with Silver Nanoparticles at Very Low Concentrations Showing No Cytotoxic Effect.

    Science.gov (United States)

    Panáček, Aleš; Smékalová, Monika; Kilianová, Martina; Prucek, Robert; Bogdanová, Kateřina; Večeřová, Renata; Kolář, Milan; Havrdová, Markéta; Płaza, Grażyna Anna; Chojniak, Joanna; Zbořil, Radek; Kvítek, Libor

    2015-12-28

    The resistance of bacteria towards traditional antibiotics currently constitutes one of the most important health care issues with serious negative impacts in practice. Overcoming this issue can be achieved by using antibacterial agents with multimode antibacterial action. Silver nano-particles (AgNPs) are one of the well-known antibacterial substances showing such multimode antibacterial action. Therefore, AgNPs are suitable candidates for use in combinations with traditional antibiotics in order to improve their antibacterial action. In this work, a systematic study quantifying the synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was performed. Employing the microdilution method as more suitable and reliable than the disc diffusion method, strong synergistic effects were shown for all tested antibiotics combined with AgNPs at very low concentrations of both antibiotics and AgNPs. No trends were observed for synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs, indicating non-specific synergistic effects. Moreover, a very low amount of silver is needed for effective antibacterial action of the antibiotics, which represents an important finding for potential medical applications due to the negligible cytotoxic effect of AgNPs towards human cells at these concentration levels.

  10. Strong and Nonspecific Synergistic Antibacterial Efficiency of Antibiotics Combined with Silver Nanoparticles at Very Low Concentrations Showing No Cytotoxic Effect

    Directory of Open Access Journals (Sweden)

    Aleš Panáček

    2015-12-01

    Full Text Available The resistance of bacteria towards traditional antibiotics currently constitutes one of the most important health care issues with serious negative impacts in practice. Overcoming this issue can be achieved by using antibacterial agents with multimode antibacterial action. Silver nano-particles (AgNPs are one of the well-known antibacterial substances showing such multimode antibacterial action. Therefore, AgNPs are suitable candidates for use in combinations with traditional antibiotics in order to improve their antibacterial action. In this work, a systematic study quantifying the synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus was performed. Employing the microdilution method as more suitable and reliable than the disc diffusion method, strong synergistic effects were shown for all tested antibiotics combined with AgNPs at very low concentrations of both antibiotics and AgNPs. No trends were observed for synergistic effects of antibiotics with different modes of action and different chemical structures in combination with AgNPs, indicating non-specific synergistic effects. Moreover, a very low amount of silver is needed for effective antibacterial action of the antibiotics, which represents an important finding for potential medical applications due to the negligible cytotoxic effect of AgNPs towards human cells at these concentration levels.

  11. Antibacterial effect and physicochemical properties of essential oil of Zataria multiflora Boiss

    Institute of Scientific and Technical Information of China (English)

    Mansour Amin; Enayat Kalantar; Neda Mohammad-Saeid; Behzad Ahsan

    2010-01-01

    Objective:To evaluate the antibacterial effect and physicochemical properties of essential oil of Zataria multiflora Boiss. Methods:Antibacterial activity of essential oil of Zataria multiflora Boiss was assessed by agar disc diffusion and minimal inhibitory concentration(MIC) was tested by E test. Results:The essential oil of Zataria multiflora Boiss was effective on pathogenic bacteria particularly Staphylococcus aureus (S. aureus). The MIC values of the target cultures ranged from 0.39 mg/mL to 1.56 mg/mL. The physicochemical properties like effects of pH, temperature, detergents, and enzymes on the activity of essential oil from Zataria multiflora Boiss were also determined. The essential oil was quite stable to temperature as tested against S. aureus and Escherichia coli (E. coli). The essential oil was very stable over a wide range of pH. The antibacterial activity of essential oil was insensitive to various protein-denaturing detergents (Such as Tween 80, Tween 20, Triton 100, etc.) and enzymes (namely proteinase K, trypsin, lipase, and lysosyme). Conclusions:A potential use of the essential oil from Zataria multiflora Boiss is suggested. More studies including further purification, mass spectra, nuclear magnetic resonance (NMR) and evaluation of toxicity are needed for confirmation of this suggestion.

  12. The non-antibacterial effects and possible clinical applications of macrolide antibiotics

    Institute of Scientific and Technical Information of China (English)

    TONG Shi-liang; WANG Yuan-liang; GAO Wen-juan

    2006-01-01

    As one group of the most widely used oral antibacterial drugs, macrolides have been clinically applied for more than 50 years because of their safety and efficacy. Recently, the non-antibacterial applications of macrolides are frequently reported, such as the therapy of malignant tumor, exudative pleurisy, pulmonary fibrosis, rheumatoid arthritis, bronchiectasis, asthma, gastrointestinal peristalsis disorders, and so on with new pharmacological effects, including reverse of tumor resistance, anti-chemical adherence, anti-fibrosis, and modulations of gastrointestinal motility as well as immune activity. The in-depth research of marcolides' non-antibiotic actions can not only extend the application fields of macrolides, but provide a new way to treat some refractory diseases.

  13. Short cationic lipopeptides as effective antibacterial agents: Design, physicochemical properties and biological evaluation.

    Science.gov (United States)

    Azmi, Fazren; Elliott, Alysha G; Marasini, Nirmal; Ramu, Soumya; Ziora, Zyta; Kavanagh, Angela M; Blaskovich, Mark A T; Cooper, Matthew A; Skwarczynski, Mariusz; Toth, Istvan

    2016-05-15

    The spread of drug-resistant bacteria has imparted a sense of urgency in the search for new antibiotics. In an effort to develop a new generation of antibacterial agents, we have designed de novo charged lipopeptides inspired by natural antimicrobial peptides. These short lipopeptides are composed of cationic lysine and hydrophobic lipoamino acids that replicate the amphiphilic properties of natural antimicrobial peptides. The resultant lipopeptides were found to self-assemble into nanoparticles. Some were effective against a variety of Gram-positive bacteria, including strains resistant to methicillin, daptomycin and/or vancomycin. The lipopeptides were not toxic to human kidney and liver cell lines and were highly resistant to tryptic degradation. Transmission electron microscopy analysis of bacteria cells treated with lipopeptide showed membrane-damage and lysis with extrusion of cytosolic contents. With such properties in mind, these lipopeptides have the potential to be developed as new antibacterial agents against drug-resistant Gram-positive bacteria.

  14. Antibacterial Effects of Cinnamon: From Farm to Food, Cosmetic and Pharmaceutical Industries

    Directory of Open Access Journals (Sweden)

    Seyed Fazel Nabavi

    2015-09-01

    Full Text Available Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided.

  15. Antibacterial Effects of Cinnamon: From Farm to Food, Cosmetic and Pharmaceutical Industries.

    Science.gov (United States)

    Nabavi, Seyed Fazel; Di Lorenzo, Arianna; Izadi, Morteza; Sobarzo-Sánchez, Eduardo; Daglia, Maria; Nabavi, Seyed Mohammad

    2015-09-11

    Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided.

  16. Oil Essential Mouthwashes Antibacterial Activity against Aggregatibacter actinomycetemcomitans: A Comparison between Antibiofilm and Antiplanktonic Effects

    Directory of Open Access Journals (Sweden)

    Matteo Erriu

    2013-01-01

    Full Text Available The aim of this work is to determine the antibacterial activity of three marketed mouthwashes on suspended and sessile states of Aggregatibacter actinomycetemcomitans. The efficacy of two commonly used products in clinical practice, containing essential oils as active ingredients (menthol, thymol, methyl salicylate, and eucalyptol in association with or without alcohol, has been evaluated in comparison with a chlorhexidine-based mouthwash. The microtiter plate assay, in order to obtain a spectrophotometric measurement of bacterial responses at growing dilutions of each antiseptic, was used for the study. The analysis revealed that a good antibacterial activity is reached when the abovementioned mouthwashes were used at concentration over a 1/24 dilution and after an exposure time of 30 seconds at least. In conclusion, the alcoholic mouthwash appears to have a better biofilm inhibition than its antiplanktonic activity while the nonalcoholic product demonstrates an opposite effect with a better antiplanktonic behavior.

  17. Antibacterial effect (in vitro) of Moringa oleifera and Annona muricata against Gram positive and Gram negative bacteria.

    Science.gov (United States)

    Viera, Gustavo Hitzschky Fernandes; Mourão, Jozeanne Alves; Angelo, Angela Maria; Costa, Renata Albuquerque; Vieira, Regine Helena Silva dos Fernandes

    2010-01-01

    Antibacterial effects of aqueous and ethanolic extracts of seeds of moringa (Moringa oleifera) and pods of soursop (Annona muricata) in the concentration of 1:5 and 1:10 in volumes 50, 100, 150 and 200 microL were examined against Staphylococcus aureus, Vibrio cholerae, Escherichia coli (isolated from the organism and the aquatic environment) and Salmonella Enteritidis. Antibacterial activity (inhibition halo > 13 mm) against S. aureus, V. cholerae and E. coli isolated from the whiteleg shrimp, Litopenaeus vannmaei, was detected in aqueous and ethanolic extracts of moringa. E. coli isolated from tilapiafish, Oreochromis niloticus, was sensitive to the ethanolic extract of moringa. The aqueous extracts of soursop showed an antibacterial effect against S. aureus and V. cholerae, but the antibacterial activity by the ethanol extracts of this plant was not demonstrated.

  18. Effect of antibacterial agents on the surface hardness of a conventional glass-ionomer cement

    Directory of Open Access Journals (Sweden)

    Tamer Tüzüner

    2012-02-01

    Full Text Available In atraumatic restorative treatment (ART, caries removal with hand excavation instruments is not as efficient as that with rotary burs in eliminating bacteria under the glass ionomer cements (GICs. Thus, different antibacterial agents have been used in recent studies to enhance the antibacterial properties of the GICs, without jeopardizing their basic physical properties. OBJECTIVE: The objective of this study was to evaluate the effect of antibacterial agents on the surface hardness of a conventional GIC (Fuji IX using Vickers microhardness [Vickers hardness number (VHN] test. MATERIAL AND METHODS: Cetrimide (CT, cetylpyridinium chloride (CPC and chlorhexidine (CHX were added to the powder and benzalkonium chloride (BC was added to the liquid of Fuji IX in concentrations of 1% and 2%, and served as the experimental groups. A control group containing no additive was also prepared. After the completion of setting reaction, VHN measurements were recorded at 1, 7, 15, 30, 60, and 90 days after storage in 37°C distilled water. A one-way ANOVA was performed followed by a Dunnett t test and Tamhane T2 tests and also repeated measurements ANOVA was used for multiple comparisons in 95% confidence interval. RESULTS: VHN results showed significant differences between the control and the experimental groups at all time periods (p<0.05 for all. Significant differences were observed between all study periods for individual groups (p<0.05. After 7 days, VHNs were decreased in all experimental groups while they continued to increase in the control group. BC and CHX groups demonstrated the least whereas CT and CPC groups exhibited most adverse effect on the hardness of set cements. CONCLUSIONS: Despite the decreased microhardness values in all experimental groups compared to the controls after 7 up to 90 days, incorporating certain antibacterial agents into Fuji IX GIC showed tolerable microhardness alterations within the limitations of this in vitro study.

  19. Antibacterial effects of Bismuth compounds and it synergy with Tetracycline and Metronidazole on Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Rajabie A

    1997-04-01

    Full Text Available Bismuth salts and different antimicrobials including Metonidazole & Tetracyclines were used in the assessment of inhibition zone of Helicobacter pylori cultures on solid media. Antibiotics were used or in combined in order to find out their possible synergistic effects. It was showed that: only Bismuth substrate and not then salts have antibacterial effects on Helicobacter pylori and also on the other bacteria such as staphylococci; salmonella and brulla. In addition, only Bismuth substrances showed remarkable synergistic effects with antimicrobial drugs against Helicobacter pylori. Therefore the data obtained from this investigation confirm previously known effect of combination antibiotic therapy including Bismuth compounds in eradicating Helicobacter pylori.

  20. Screening, Identification and Antibacterial Activities of Effective Thermotolerant Bacillus spp. Strains Isolated from Raw Milk

    Directory of Open Access Journals (Sweden)

    Kannikar SANTONG

    2008-01-01

    Full Text Available Forty-one isolates of Bacillus species were isolated from raw milk, analyzed using the spot on lawn and agar diffusion method in terms of their general inhibition effects to test bacteria (Escherichia coli TISTR 887 and Staphylococcus aureus TISTR 517. The results demonstrated that most isolates are effective against Gram-positive and Gram-negative bacteria whereas their extensive inhibition effect is particularly against Gram-positive bacteria. Only 2 effective thermotolerant isolates, BA8 and BA16, exerted broad spectrum antibacterial activities against both test bacteria.  Based on biochemical and physiological properties, they were classified as Brevibacillus laterosporus and Geobacillus thermoglucosidasius, respectively.

  1. Synthesis, characterization and antibacterial effect of new magnetically core–shell nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Allafchian, Alireza, E-mail: Allafchian@cc.iut.ac.ir [Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan 84156 83111 (Iran, Islamic Republic of); Bahramian, Hamid [Department of physics, Isfahan University of Technology, Isfahan 84156 83111 (Iran, Islamic Republic of); Hossein Jalali, Seyed Amir [Institute of Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan 84156 83111 (Iran, Islamic Republic of); Ahmadvand, Hossein [Department of physics, Isfahan University of Technology, Isfahan 84156 83111 (Iran, Islamic Republic of)

    2015-11-15

    A new magnetically responsive three-component nanocomposite consisting of NiFe{sub 2}O{sub 4}, Poly Acrylonitrile Co Maleic Anhydride (PAMA) and nanosilver was synthesized and characterized and then its antibacterial activities were tested. For the preparation of NiFe{sub 2}O{sub 4}@Ag, NiFe{sub 2}O{sub 4} was coated by Ag and for the synthesis of NiFe{sub 2}O{sub 4}@PAMA@Ag, NiFe{sub 2}O{sub 4} was first covered by PAMA and then silver nanoparticles were immobilized on the surface of the PAMA shell. The nanocomposites were studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The antibacterial activity of the synthesized nanocomposite against some gram positive and gram negative bacteria was studied and compared with that of naked NiFe{sub 2}O{sub 4}, NiFe{sub 2}O{sub 4}@Ag and NiFe{sub 2}O{sub 4}@PAMA. The NiFe{sub 2}O{sub 4}@PAMA@Ag had better antibacterial activity and could be readily isolated from the aqueous solution via magnetic decantation, thereby avoiding the contamination of the environment. - Highlights: • A novel NiFe{sub 2}O{sub 4}@PAMA@Ag nanocomposites magnetic composite has been prepared. • This system display potent antimicrobial activity toward some bacterial species. • The antibacterial effect was studied by disk diffusion method. • This composite can be easily removed from solution by magnetic decantation.

  2. Biodegradable Mg-Cu alloys with enhanced osteogenesis, angiogenesis, and long-lasting antibacterial effects

    Science.gov (United States)

    Liu, Chen; Fu, Xuekun; Pan, Haobo; Wan, Peng; Wang, Lei; Tan, Lili; Wang, Kehong; Zhao, Ying; Yang, Ke; Chu, Paul K.

    2016-01-01

    A series of biodegradable Mg-Cu alloys is designed to induce osteogenesis, stimulate angiogenesis, and provide long-lasting antibacterial performance at the same time. The Mg-Cu alloys with precipitated Mg2Cu intermetallic phases exhibit accelerated degradation in the physiological environment due to galvanic corrosion and the alkaline environment combined with Cu release endows the Mg-Cu alloys with prolonged antibacterial effects. In addition to no cytotoxicity towards HUVECs and MC3T3-E1 cells, the Mg-Cu alloys, particularly Mg-0.03Cu, enhance the cell viability, alkaline phosphatase activity, matrix mineralization, collagen secretion, osteogenesis-related gene and protein expressions of MC3T3-E1 cells, cell proliferation, migration, endothelial tubule forming, angiogenesis-related gene, and protein expressions of HUVECs compared to pure Mg. The favorable osteogenesis and angiogenesis are believed to arise from the release of bioactive Mg and Cu ions into the biological environment and the biodegradable Mg-Cu alloys with osteogenesis, angiogenesis, and long-term antibacterial ability are very promising in orthopedic applications. PMID:27271057

  3. Controlled release behaviour and antibacterial effects of antibiotic-loaded titania nanotubes.

    Science.gov (United States)

    Feng, Wenchao; Geng, Zhen; Li, Zhaoyang; Cui, Zhenduo; Zhu, Shengli; Liang, Yanqin; Liu, Yunde; Wang, Renfeng; Yang, Xianjin

    2016-05-01

    Bacterial infections have been identified as the main cause of orthopaedic implant failure. Owing to their high antibiotic delivery efficiency, titania nanotubes loaded with antibiotics constitute one of the most promising strategies for suppressing bacterial infections. However, it is difficult to control the drug-release behaviour of such nanotubes. Although sealing the nanotubes with a polymer solution provides sustained release effects to a certain extent, it inevitably influences their initial antibacterial activity. This study reports on the controlled release of gentamicin sulphate (GS) from titania nanotube surfaces whereby their initial antibacterial activity remains unaffected. Titania nanotubes were fabricated via electrochemical anodization and loaded with GS through physical adsorption. Experimental results showed that this loading method is feasible and efficient. The GS-loaded titania nanotubes were further covered by a thin film comprising a mixture of GS and chitosan (GSCH). The release kinetics confirmed that the drug release could be controlled by this thin film. Moreover, such a film was shown to not only inhibit initial bacterial adherence owing to its strong antibacterial properties but also enhance cell viability. Thus, GS-loaded titania nanotubes coated with GSCH have considerable potential as biomaterials for preventing initial release and peri-implant infection in the field of orthopaedics.

  4. The anti-angiogenic and antibacterial effect of Tinomiscium philippinense Miers. (Menispermaceae leaf extract

    Directory of Open Access Journals (Sweden)

    Sheryl Rena-Aguila

    2016-01-01

    Full Text Available Objective: To determine the toxicity profile, anti-angiogenic and antibacterial activity of the crude and semi-crude leaf extracts of Tinomiscium philippinense (T. philippinense. Methods: The leaves of T. philippinense were extracted with methanol and partitioned with solvents of different polarities, namely, hexane, dichloromethane and butanol. The extracts were subjected to duck chorioallantoic membrane assay to establish its anti-angiogenic property. Microwell assay was utilized to determine the minimum inhibitory concentration and minimum bactericidal concentration of the different extracts of the plant. Results: The dichloromethane leaf extract of T. philippinense at 1 000 µg/disc showed the highest anti-angiogenic activity with 37.46% inhibition. All the fractions exhibited a bacteriostatic and bactericidal effect on the three bacterial strains with Pseudomonas aeruginosa, a Gram negative lactose fermenter exhibiting a higher sensitivity to dichloromethane semi-crude extract among the treatment groups. For the toxicity test, no mortality and no change in behavior were observed in the Sprague-Dawley rats 14 days after the oral administration of the plant extracts. The methanolic leaf extract of T. philippinense is non-toxic at a maximum dose of 5000 mg/kg. Conclusions: The dichloromethane leaf extract of T. philippinense is a potential antiangiogenic endemic plant species. This plant extract is also a potential antibacterial candidate as determined by microwell assay. The anti-angiogenic and antibacterial activity of the plant may be attributed to the essential oil, steroid, flavonoid, sterol and triterpene content of the plant.

  5. Nanostructured molybdenum oxide-based antibacterial paint: effective growth inhibition of various pathogenic bacteria

    Science.gov (United States)

    Krishnamoorthy, Karthikeyan; Premanathan, Mariappan; Veerapandian, Murugan; Kim, Sang Jae

    2014-08-01

    The prevention of bacterial infections in the health care environment is paramount to providing better treatment. Covering a susceptible environment with an antimicrobial coating is a successful way to avoid bacterial growth. Research on the preparation of durable antimicrobial coatings is promising for both fundamental surface care and clinical care applications. Herein, we report a facile, efficient, and scalable preparation of MoO3 paint using a cost-effective ball-milling approach. The MoO3 nanoplates (synthesized by thermal decomposition of ammonium heptamolybdate) are used as a pigment and antibacterial activity moiety in alkyd resin binders and other suitable eco-friendly additives in the preparation of paint. Surface morphology, chemical states, bonding nature, and intermolecular interaction between the MoO3 and the alkyd resin were studied using Raman and x-ray photoelectron spectroscopic analysis. The antibacterial properties of a prepared MoO3 nanoplate against various bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae) was determined using the microdilution method. Bacterial strains exposed to an MoO3 paint coated surface exhibit a significant loss of viability in a time-dependent manner. Fundamental modes of antibacterial activities ascribed from a biocompatible and durable MoO3 nanostructure incorporated into an alkyd resin complex are discussed. The obtained experimental findings suggest the potential utility of prepared MoO3-based paint coating for the prevention of health care associated infections.

  6. Biodegradable Mg-Cu alloys with enhanced osteogenesis, angiogenesis, and long-lasting antibacterial effects.

    Science.gov (United States)

    Liu, Chen; Fu, Xuekun; Pan, Haobo; Wan, Peng; Wang, Lei; Tan, Lili; Wang, Kehong; Zhao, Ying; Yang, Ke; Chu, Paul K

    2016-06-07

    A series of biodegradable Mg-Cu alloys is designed to induce osteogenesis, stimulate angiogenesis, and provide long-lasting antibacterial performance at the same time. The Mg-Cu alloys with precipitated Mg2Cu intermetallic phases exhibit accelerated degradation in the physiological environment due to galvanic corrosion and the alkaline environment combined with Cu release endows the Mg-Cu alloys with prolonged antibacterial effects. In addition to no cytotoxicity towards HUVECs and MC3T3-E1 cells, the Mg-Cu alloys, particularly Mg-0.03Cu, enhance the cell viability, alkaline phosphatase activity, matrix mineralization, collagen secretion, osteogenesis-related gene and protein expressions of MC3T3-E1 cells, cell proliferation, migration, endothelial tubule forming, angiogenesis-related gene, and protein expressions of HUVECs compared to pure Mg. The favorable osteogenesis and angiogenesis are believed to arise from the release of bioactive Mg and Cu ions into the biological environment and the biodegradable Mg-Cu alloys with osteogenesis, angiogenesis, and long-term antibacterial ability are very promising in orthopedic applications.

  7. Effects of antibacterial nanostructured composite films on vascular stents: hemodynamic behaviors, microstructural characteristics, and biomechanical properties.

    Science.gov (United States)

    Cheng, Han-Yi; Hsiao, Wen-Tien; Lin, Li-Hsiang; Hsu, Ya-Ju; Sinrang, Andi Wardihan; Ou, Keng-Liang

    2015-01-01

    The purpose of this research was to investigate stresses resulting from different thicknesses and compositions of hydrogenated Cu-incorporated diamond-like carbon (a-C:H/Cu) films at the interface between vascular stent and the artery using three-dimensional reversed finite element models (FEMs). Blood flow velocity variation in vessels with plaques was examined by angiography, and the a-C:H/Cu films were characterized by transmission electron microscopy to analyze surface morphology. FEMs were constructed using a computer-aided reverse design system, and the effects of antibacterial nanostructured composite films in the stress field were investigated. The maximum stress in the vascular stent occurred at the intersections of net-like structures. Data analysis indicated that the stress decreased by 15% in vascular stents with antibacterial nanostructured composite films compared to the control group, and the stress decreased with increasing film thickness. The present results confirmed that antibacterial nanostructured composite films improve the biomechanical properties of vascular stents and release abnormal stress to prevent restenosis. The results of the present study offer the clinical benefit of inducing superior biomechanical behavior in vascular stents.

  8. Inhibitory effects of acyclic nucleoside phosphonates on human hepatitis B virus and duck hepatitis B virus infections in tissue culture

    NARCIS (Netherlands)

    R.A. Heijtink; J. Kruining; G.A. de Wilde; J. Balzarini; E. de Clercq; S.W. Schalm (Solko)

    1994-01-01

    textabstractThe inhibitory effects of the 9-(2-phosphonylmethoxyethyl)adenine-related compounds (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)-adenine, (S)-9-(3-fluoro-2-phosphonylmethoxypropyl)adenine, (R)-9-(2-phosphonylmethoxypropyl)adenine, (R)-9-(2-phosphony

  9. Effects of Nitrogen Concentration on Microstructure and Antibac-terial Property of Copper-Bearing Austenite Stainless Steels

    Institute of Scientific and Technical Information of China (English)

    Zhixia ZHANG; Laizhu JIANG; Gang LIN; Zhou XU

    2008-01-01

    Austenite antibacterial stainless steels have been found to have wide applications in hospitals and food indus-tries. In recent years epsilon copper precipitation in antibacterial stainless steels has obtained much research interest due to its antibacterial action. The objective of this study was to determine the effects of nitro-gen concentration on the precipitation of epsilon copper and antibacterial property. Two kinds of austenite antibacterial stainless steels containing copper and different nitrogen concentration (0.02 and 0.08 wt pct, re-spectively) were prepared and the microstructures were characterized by a combination of electron microscopy and thermodynamic analysis. A mathematical expression was deduced to predict the effect of nitrogen con-centration on the activity coefficient of copper, In(fCu/focu)=0.53524+4.11xN-0.48x2N. Higher nitrogen was found to increase the free energy difference of copper concentration distribution between precipitation phase and austenite matrix, stimulate the aggregation of copper atoms from austenite, increase the precipitation amount and consequently enhance the antibacterial property of steel.

  10. Comparison of Antibacterial Effect of Fluoride and Chlorhexidine on Two Cariogenic Bacteria: An in Vitro Study

    Directory of Open Access Journals (Sweden)

    Poureslami HR

    2014-09-01

    Full Text Available Statement of problem: Dental plaque is the main source for dental caries and there is no proper vaccine that can affect dental plaques. Objectives: Daily use of an efficient anti-plaque product can be very beneficial in plaque control and, thus, prevention of caries. This study aims to evaluate the antibacterial effects of four products of Chlorhexidine and Fluoride on two types of cariogenic bacteria. Materials and Methods: In this in vitro study, the antibacterial effect of Chlorhexidine and Fluoride (gel and solution against Streptococci Sanguis and Sobrinus was evaluated. Chlorhexidine gluconate 1% gel (Corosodyl, France, Chlorhexidine gluconate 2% solution (Consepsis, Ultradent, US, Sodium fluoride 0.2% solution (Oral-B, US and Acidulated Phosphate Fluoride 1.23% gel ( Denti-Care, Canada were used. The disc diffusion method was used for testing bacterial sensitivity. The data were analyzed using paired t-test and Chi-square test. Results: In comparison with the negative control, each of the four gels and solutions showed antibacterial effects but the effects were not statistically significant for fluoride solution (P=0.217. For S. Sobrinus, the mean diameter of inhibition zone around the discs coated with fluoride gel (F g, fluoride solution (F s, Chlorhexidine gel (CHX g and Chlorhexidine solution (CHX s were 19, 9, 21.5 and 27.5mm, respectively. For S. Sanguis, the mean diameter of inhibition zone around the discs coated with F g, F s, CHX g and CHX s were 17, 11, 17 and 25mm, respectively. CHX s had the most effect on both bacteria and F s had the least. CHX g and F g were less effective than CHX s, respectively. Conclusion: The results demonstrated that 2% CHX s and 1.23% F g can be effective on inhibition of the growth of some of cariogenic bacteria. Therefore, these agents can be used in the prevention of Early Childhood Caries.

  11. Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite

    Institute of Scientific and Technical Information of China (English)

    Ke Zhang; Lei Cheng; Michael D Weir; Yu-Xing Bai; Hockin HK Xu

    2016-01-01

    Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs) of 3–18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized: DMAPM (CL3), DMAHM (CL6), DMADDM (CL12), DMAHDM (CL16), and DMAODM (CL18). Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite (n 5 6; P . 0.1). Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite (P , 0.05); further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units (CFU) of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3–18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the CL reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit

  12. Effects of alprostadil on blood rheology and nucleoside metabolism in patients affected with lower limb chronic ischaemia.

    Science.gov (United States)

    Acciavatti, A; Laghi Pasini, F; Capecchi, P L; Messa, G L; Lazzerini, P E; De Giorgi, L; Acampa, M; Di Perri, T

    2001-01-01

    The acute (0.57 microg/kg i.v. in 2 hours) and long-term (0.57 microg/kg i.v. in 2 hours for 5 days over 4 weeks) effects of the PGE1 analogue alprostadil were studied in patients affected with intermittent claudication. Whole Blood Viscosity (WBV), Whole Blood Filterability (WBF), haematocrit (Htc) and fibrinogen plasma concentration, were studied together with P50, 2,3-diphosphoglycerate, and adenosine plasma levels. Moreover, in the long-term study, pain-free (PFWD) and maximal walking distance (MWD) were measured. Single alprostadil infusion induced an improvement in WBV, WBF, and oxygen transport, and an increase in adenosine plasma levels. Long-term alprostadil administration produced a decrease in WBV only, without significant changes in WBF, Htc, fibrinogen, P50, 2,3-diphosphoglycerate, also inducing a significant prolongation of PFWD and MWD. The possibility is suggested that pulse rises in adenosine plasma levels play a role in the effects of chronic alprostadil administration, maybe in a way similar to that observed in the phenomenon of ischaemic preconditioning,

  13. Synergistic Antibacterial Effects of Nanoparticles Encapsulated with Scutellaria baicalensis and Pure Chlorhexidine on Oral Bacterial Biofilms

    Directory of Open Access Journals (Sweden)

    Ken Cham-Fai Leung

    2016-04-01

    Full Text Available Scutellaria baicalensis (SB is a traditional Chinese medicine for treating infectious and inflammatory diseases. Our recent study shows potent antibacterial effects of nanoparticle-encapsulated chlorhexidine (Nano-CHX. Herein, we explored the synergistic effects of the nanoparticle-encapsulated SB (Nano-SB and Nano-CHX on oral bacterial biofilms. Loading efficiency of Nano-SB was determined by thermogravimetric analysis, and its releasing profile was assessed by high-performance liquid chromatographyusing baicalin (a flavonoid compound of SB as the marker. The mucosal diffusion assay on Nano-SB was undertaken in a porcine model. The antibacterial effects of the mixed nanoparticles (Nano-MIX of Nano-SB and Nano-CHX at 9:1 (w/w ratio were analyzed in both planktonic and biofilm modes of representative oral bacteria. The Nano-MIX was effective on the mono-species biofilms of Streptococcus (S. mutans, S. sobrinus, Fusobacterium (F. nucleatum, and Aggregatibacter (A. actinomycetemcomitans (MIC 50 μg/mL at 24 h, and exhibited an enhanced effect against the multi-species biofilms such as S. mutans, F. nucleatum, A. actinomycetemcomitans, and Porphyromonas (P. gingivalis (MIC 12.5 μg/mL at 24 h that was supported by the findings of both scanning electron microscopy (SEM and confocal scanning laser microscopy (CLSM. This study shows enhanced synergistic antibacterial effects of the Nano-MIX on common oral bacterial biofilms, which could be potentially developed as a novel antimicrobial agent for clinical oral/periodontal care.

  14. THE REGULATORY EFFECT OF NUCLEOSIDE DIPHOSPHATE KINASE ON G-PROTEIN AND G-PROTEIN MEDIATED PHOSPHOLIPASE C

    Institute of Scientific and Technical Information of China (English)

    张德昌; 张宽仁

    1995-01-01

    The effect of nueleoside diphosphate kinase (NDPK) on the activity of guanine nueleotide regulatory protein (G-protein) mediated phospholipase C (PLC) and on the [35S ] GTPTτS binding of G-protein was investigated in this work in order to demonstrate the mechanism behind the regulation of G-protein and its effector PLC by NDPK. The stimulation of PLC in turkey erythrocyte membrane by both GTP and GTPτS indicated that the PLC stimulation was msdiated by G-protein, NDPK alone stimulated PLC activity, as well as the stimulation in the presence of GTP and GDP, in a dose-dependent manner. However, NDPK inhibited GTPτS-stimulated PLC, Furthermore, NDPK inhibited [35S] GTPτS binding of purified Gi-protein in a non-competitive manner. A hypothesis implying an important role of direct interaction of G-protein and NDPK in the regulation of their functions is suggested and discussed.

  15. Lack of effect of cell-wall targeted antibacterials on biofilm formation and antifungal susceptibility of Candidaspecies

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    Gisela Myrian de Lima Leite

    2014-09-01

    Full Text Available The use of central venous catheters (CVC and broad-spectrum antibacterials are among the main risk factors for the development of candidemia in patients admitted to intensive care units (ICU. It is known that some antibacterials increase the resistance of these yeasts to azole antifungals. Thus, the aim of this research was to determine whether yeast present in CVC colonizations previously exposed to cell-wall targeted antibacterials benefit from a reduction in susceptibility to fluconazole and voriconazole, facilitating their ability to form biofilms. Candida albicans, C. tropicalis, C. glabrata, C. parapsilosis and C. guilhermondii were seeded into antibacterial (cefepime, meropenem, vancomycin, and piperacillin-tazobactam gradient plates produced in Mueller-Hinton Agar. The susceptibility to fluconazole and voriconazole and the biofilm formation of the yeasts were tested before and after exposure to the antibacterials. None of the antibacterials exerted a significant effect on the in vitro susceptibility of the yeasts to the antifungal agents or on their ability to form biofilms. These results suggest that increased candidemia in ICU patients is not attributable to possible alterations in the yeasts, but is more likely caused by a weakening of the patient's general condition after long exposure to infection.

  16. Antioxidant,antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract

    Institute of Scientific and Technical Information of China (English)

    Md; Atiar; Rahman; Md; Saiful; Islam

    2013-01-01

    Objective:To investigate the antioxidant,antibacterial and cytotoxic activity of whole Leucas aspera(Labiatae)(L.aspera)alcoholic extract.Methods:Whole L.aspera powder was extracted by absolute ethanol(99.50%).The ethanolic extract was subjected to antioxidant,antibacterial and brine shrimp lethality assay.Results:The extract showed potent radical scavenging effect(antioxidant)with IC50value of(99.58±1.22)μg/mL which was significant(P<0.01)in comparison to ascorbic acid with IC50value of(1.25±0.95)μg/mL.In case of antibacterial screening,the extract showed notable antibacterial effect against the tested microbial strains.Significant(P<0.05)zone of inhibitions against Gram positive Bacillus subtilis[(12.00±1.32)mm]and Bacillus megaterium[(13.00±1.50)mm],Staphylococcus aureus[(8.00±0.50)mm]and Gram negative Salmonella typhi[(6.00±0.50)mm],Salmonella paratyphi[(8.00±1.00)mm],Shigella dysenteriae[(9.00±1.32)mm]and Vibrio cholerae[(9.00±0.66)mm]was observed.In brine shrimp lethality bioassay,the extract showed the LC50value as(181.68±2.15)μg/mL which was statistically significant(P<0.01)compared to positive control vincristine sulfate[LC50=(0.76±0.04)μg/mL].Conclusions:The results demonstrate that the ethanolic extract of L.aspera could be used as antibacterial,pesticidal and various pharmacologic actives.

  17. Photodynamic therapy for inactivating endodontic bacterial biofilms and effect of tissue inhibitors on antibacterial efficacy

    Science.gov (United States)

    Shrestha, Annie; Kishen, Anil

    Complex nature of bacterial cell membrane and structure of biofilm has challenged the efficacy of antimicrobial photodynamic therapy (APDT) to achieve effective disinfection of infected root canals. In addition, tissue-inhibitors present inside the root canals are known to affect APDT activity. This study was aimed to assess the effect of APDT on bacterial biofilms and evaluate the effect of tissue-inhibitors on the APDT. Rose-bengal (RB) and methylene-blue (MB) were tested on Enterococcus faecalis (gram-positive) and Pseudomonas aeruginosa (gram-negative) biofilms. In vitro 7- day old biofilms were sensitized with RB and MB, and photodynamically activated with 20-60 J/cm2. Photosensitizers were pre-treated with different tissue-inhibitors (dentin, dentin-matrix, pulp tissue, bacterial lipopolysaccharides (LPS), and bovine serum albumin (BSA)) and tested for antibacterial effect of APDT. Microbiological culture based analysis was used to analyze the cell viability, while Laser Scanning Confocal Microscopy (LSCM) was used to examine the structure of biofilm. Photoactivation resulted in significant reduction of bacterial biofilms with RB and MB. The structure of biofilm under LSCM was found to be disrupted with reduced biofilm thickness. Complete biofilm elimination could not be achieved with both tested photosensitizers. APDT effect using MB and RB was inhibited in a decreasing order by dentin-matrix, BSA, pulp, dentin and LPS (P< 0.05). Both strains of bacterial biofilms resisted complete elimination after APDT and the tissue inhibitors existing within the root canal reduced the antibacterial activity at varying degrees. Further research is required to enhance the antibacterial efficacy of APDT in an endodontic environment.

  18. Antibacterial Effect of Hydroalcoholic Extract of Punica granatum Linn. Petal on Common Oral Microorganisms.

    Science.gov (United States)

    Hajifattahi, Farnaz; Moravej-Salehi, Elham; Taheri, Maryam; Mahboubi, Arash; Kamalinejad, Mohammad

    2016-01-01

    Objectives. This study aimed to assess the effect of hydroalcoholic extract of Punica granatum Linn. (P. granatum) petal on Streptococcus sanguinis, Streptococcus mutans, Streptococcus salivarius, Streptococcus sobrinus, and Enterococcus faecalis. Materials and Methods. In this in vitro study, P. granatum extract was prepared using powdered petals and water-ethanol solvent. Antibacterial effect of the extract, chlorhexidine (CHX), and ampicillin was evaluated on brain heart infusion agar (BHIA) using the cup-plate method. By assessing the diameter of the growth inhibition zone, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract were determined for the above-mentioned bacteria. Results. Hydroalcoholic extract of P. granatum petal had inhibitory effects on the proliferation of all five bacterial strains with maximum effect on S. mutans with MIC and MBC of 3.9 mg/mL. The largest growth inhibition zone diameter belonged to S. sanguinis and the smallest to E. faecalis. Ampicillin and CHX had the greatest inhibitory effect on S. sanguinis. Conclusions. Hydroalcoholic extract of P. granatum had a significant antibacterial effect on common oral bacterial pathogens with maximum effect on S. mutans, which is the main microorganism responsible for dental plaque and caries.

  19. Deodorant effects of a sage extract stick: Antibacterial activity and sensory evaluation of axillary deodorancy

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Shahtalebi

    2013-01-01

    Full Text Available Background: Deodorant products prevent the growth and activity of the degrading apocrine gland bacteria living in the armpit. Common antibacterial agents in the market like triclosan and aluminum salts, in spite of their suitable antibacterial effects, increase the risk of Alzheimer′s disease, breast and prostate cancers or induce contact dermatitis. Therefore, plant extracts possessing antibacterial effects are of interest. The aim of the present study was to verify the in vitro antimicrobial effects of different sage extracts against two major bacteria responsible for axillary odor, and to evaluate the deodorant effect of a silicon-based stick containing sage extracts in different densities in humans. Materials and Methods: Different fractions of methanolic extract of Salvia officinalis (sage were evaluated on a culture of armpit skin surface of volunteers through agar microdilution antimicrobial assay. Then, randomized, double-blind placebo-controlled clinical trial with the best antibacterial fraction was conducted on 45 female healthy volunteers. Participants were treated with a single dose in four groups, each containing 15 individuals: Group 1 (200 μg/mL, 2 (400 μg/mL, 3 (600 μg/mL of dichloromethane sage extract, and placebo (without extract. A standard sensory evaluation method for the evaluation of deodorant efficacy was used before, and two hours, four hours, and eight hours after single application of a deodorant or placebo (ASTM method E 1207-87 Standard Practice for the Sensory Evaluation of Axillary Deodorancy. Results: The data were analyzed with two factors relating to densities and time. In 45 participants with a mean [± standard deviation (SD] age of 61.5±11.8 years, statistically significant within-group differences were observed before and two, four, and eight hours after deodorant treatment for groups 1, 2, and 3. Groups 1, 2, and 3 had a significantly smaller odor score than placebo after two, four, and eight hours

  20. Antibacterial Effect of Dental Adhesive Containing Dimethylaminododecyl Methacrylate on the Development of Streptococcus mutans Biofilm

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    Suping Wang

    2014-07-01

    Full Text Available Antibacterial bonding agents and composites containing dimethylaminododecyl methacrylate (DMADDM have been recently developed. The objectives of this study were to investigate the antibacterial effect of novel adhesives containing different mass fractions of DMADDM on Streptococcus mutans (S. mutans biofilm at different developmental stages. Different mass fractions of DMADDM were incorporated into adhesives and S. mutans biofilm at different developmetal stages were analyzed by MTT assays, lactic acid measurement, confocal laser scanning microscopy and scanning electron microscopy observations. Exopolysaccharides (EPS staining was used to analyze the inhibitory effect of DMADDM on the biofilm extracellular matrix. Dentin microtensile strengths were also measured. Cured adhesives containing DMADDM could greatly reduce metabolic activity and lactic acid production during the development of S. mutans biofilms (p < 0.05. In earlier stages of biofilm development, there were no significant differences of inhibitory effects between the 2.5% DMADDM and 5% DMADDM group. However, after 72 h, the anti-biofilm effects of adhesives containing 5% DMADDM were significantly stronger than any other group. Incorporation of DMADDM into adhesive did not adversely affect dentin bond strength. In conclusion, adhesives containing DMADDM inhibited the growth, lactic acid production and EPS metabolism of S. mutans biofilm at different stages, with no adverse effect on its dentin adhesive bond strength. The bonding agents have the potential to control dental biofilms and combat tooth decay, and DMADDM is promising for use in a wide range of dental adhesive systems and restoratives.

  1. Antibacterial effect of dental adhesive containing dimethylaminododecyl methacrylate on the development of Streptococcus mutans biofilm.

    Science.gov (United States)

    Wang, Suping; Zhang, Keke; Zhou, Xuedong; Xu, Ning; Xu, Hockin H K; Weir, Michael D; Ge, Yang; Wang, Shida; Li, Mingyun; Li, Yuqing; Xu, Xin; Cheng, Lei

    2014-07-18

    Antibacterial bonding agents and composites containing dimethylaminododecyl methacrylate (DMADDM) have been recently developed. The objectives of this study were to investigate the antibacterial effect of novel adhesives containing different mass fractions of DMADDM on Streptococcus mutans (S. mutans) biofilm at different developmental stages. Different mass fractions of DMADDM were incorporated into adhesives and S. mutans biofilm at different developmetal stages were analyzed by MTT assays, lactic acid measurement, confocal laser scanning microscopy and scanning electron microscopy observations. Exopolysaccharides (EPS) staining was used to analyze the inhibitory effect of DMADDM on the biofilm extracellular matrix. Dentin microtensile strengths were also measured. Cured adhesives containing DMADDM could greatly reduce metabolic activity and lactic acid production during the development of S. mutans biofilms (p biofilm development, there were no significant differences of inhibitory effects between the 2.5% DMADDM and 5% DMADDM group. However, after 72 h, the anti-biofilm effects of adhesives containing 5% DMADDM were significantly stronger than any other group. Incorporation of DMADDM into adhesive did not adversely affect dentin bond strength. In conclusion, adhesives containing DMADDM inhibited the growth, lactic acid production and EPS metabolism of S. mutans biofilm at different stages, with no adverse effect on its dentin adhesive bond strength. The bonding agents have the potential to control dental biofilms and combat tooth decay, and DMADDM is promising for use in a wide range of dental adhesive systems and restoratives.

  2. Synergistic Antibacterial Effects of Polyphenolic Compounds from Olive Mill Wastewater

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    Ahmed Tafesh

    2011-01-01

    Full Text Available Polyphenols or phenolic compounds are groups of secondary metabolites widely distributed in plants and found in olive mill wastewater (OMW. Phenolic compounds as well as OMW extracts were evaluated in vitro for their antimicrobial activity against Gram-positive (Streptococcus pyogenes and Staphylococcus aureus and Gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae. Most of the tested phenols were not effective against the four bacterial strains when tested as single compounds at concentrations of up to 1000 μg mL−1. Hydroxytyrosol at 400 μg mL−1 caused complete growth inhibition of the four strains. Gallic acid was effective at 200, and 400 μg mL−1 against S. aureus, and S. pyogenes, respectively, but not against the gram negative bacteria. An OMW fraction called AntiSolvent was obtained after the addition of ethanol to the crude OMW. HPLC analysis of AntiSolvent fraction revealed that this fraction contains mainly hydroxytyrosol (10.3%, verbascoside (7.4%, and tyrosol (2.6%. The combinations of AntiSolvent/gallic acid were tested using the low minimal inhibitory concentrations which revealed that 50/100–100/100 μg mL−1 caused complete growth inhibition of the four strains. These results suggest that OMW specific fractions augmented with natural phenolic ingredients may be utilized as a source of bioactive compounds to control pathogenic bacteria.

  3. In vitro antibacterial effect of carbamide peroxide on oral biofilm

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    Chao Shu Yao

    2013-06-01

    Full Text Available This study compared the effects of carbamide peroxide (CP and chlorhexidine (CHX on oral biofilm in vitro. Collagen-coated hydroxyapatite discs were inoculated with subgingival plaque. After 3 weeks, the emergent biofilms were subjected to 1-, 3-, and 10-min exposures of a 1% CHX gel, a 5% CP gel and rinse, and a 10% CP gel and rinse. Subsequently, the biofilms were stained using a two-colour fluorescent dye kit for confocal laser scanning microscopy, and the volume ratio of dead bacteria to all bacteria was analysed. Compared to a non-treated gel control, the active agents killed bacteria on all the discs, with higher concentration and longer exposure times killing more bacteria. The rinse form disrupted the biofilm quicker than the gel form. Overall, 10% CP showed more disruption of biofilm and a greater proportion of killed bacteria than 1% CHX (p<0.05.

  4. The photodynamic antibacterial effects of silicon phthalocyanine (Pc) 4.

    Science.gov (United States)

    Dimaano, Matthew L; Rozario, Chantal; Nerandzic, Michelle M; Donskey, Curtis J; Lam, Minh; Baron, Elma D

    2015-04-08

    The emergence of antibiotic-resistant strains in facultative anaerobic Gram-positive coccal bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), is a global health issue. Typically, MRSA strains are found associated with institutions like hospitals but recent data suggest that they are becoming more prevalent in community-acquired infections. It is thought that the incidence and prevalence of bacterial infections will continue to increase as (a) more frequent use of broad-spectrum antibiotics and immunosuppressive medications; (b) increased number of invasive medical procedures; and (c) higher incidence of neutropenia and HIV infections. Therefore, more optimal treatments, such as photodynamic therapy (PDT), are warranted. PDT requires the interaction of light, a photosensitizing agent, and molecular oxygen to induce cytotoxic effects. In this study, we investigated the efficacy and characterized the mechanism of cytotoxicity induced by photodynamic therapy sensitized by silicon phthalocyanine (Pc) 4 on (a) methicillin-sensitive Staphylococcus aureus (MSSA) (ATCC 25923); (b) community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) (ATCC 43300); and (c) hospital acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) (PFGE type 300). Our data include confocal image analysis, which confirmed that Pc 4 is taken up by all S. aureus strains, and viable cell recovery assay, which showed that concentrations as low as 1.0 μM Pc 4 incubated for 3 h at 37 °C followed by light at 2.0 J/cm2 can reduce cell survival by 2-5 logs. These results are encouraging, but before PDT can be utilized as an alternative treatment for eradicating resistant strains, we must first characterize the mechanism of cell death that Pc 4-based PDT employs in eliminating these pathogens.

  5. The Photodynamic Antibacterial Effects of Silicon Phthalocyanine (Pc 4

    Directory of Open Access Journals (Sweden)

    Matthew L. Dimaano

    2015-04-01

    Full Text Available The emergence of antibiotic-resistant strains in facultative anaerobic Gram-positive coccal bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA, is a global health issue. Typically, MRSA strains are found associated with institutions like hospitals but recent data suggest that they are becoming more prevalent in community-acquired infections. It is thought that the incidence and prevalence of bacterial infections will continue to increase as (a more frequent use of broad-spectrum antibiotics and immunosuppressive medications; (b increased number of invasive medical procedures; and (c higher incidence of neutropenia and HIV infections. Therefore, more optimal treatments, such as photodynamic therapy (PDT, are warranted. PDT requires the interaction of light, a photosensitizing agent, and molecular oxygen to induce cytotoxic effects. In this study, we investigated the efficacy and characterized the mechanism of cytotoxicity induced by photodynamic therapy sensitized by silicon phthalocyanine (Pc 4 on (a methicillin-sensitive Staphylococcus aureus (MSSA (ATCC 25923; (b community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA (ATCC 43300; and (c hospital acquired methicillin-resistant Staphylococcus aureus (HA-MRSA (PFGE type 300. Our data include confocal image analysis, which confirmed that Pc 4 is taken up by all S. aureus strains, and viable cell recovery assay, which showed that concentrations as low as 1.0 μM Pc 4 incubated for 3 h at 37 °C followed by light at 2.0 J/cm2 can reduce cell survival by 2–5 logs. These results are encouraging, but before PDT can be utilized as an alternative treatment for eradicating resistant strains, we must first characterize the mechanism of cell death that Pc 4-based PDT employs in eliminating these pathogens.

  6. Antibacterial effect and cytotoxicity of Ag-doped functionally graded hydroxyapatite coatings.

    Science.gov (United States)

    Bai, Xiao; Sandukas, Stefan; Appleford, Mark; Ong, Joo L; Rabiei, Afsaneh

    2012-02-01

    Functionally graded hydroxyapatite coatings (FGHA) doped with 1, 3, and 6.5 wt % silver (Ag) have been deposited on Titanium using ion-beam-assisted deposition. Scanning transmission electron microscopy on coating cross sections confirmed the presence of FGHA coating with mostly amorphous layers at the top and mostly crystalline layers toward the coating interface as well as the existence of 10-50 nm Ag particles distributed throughout the thickness of the coatings. Calcium release in phosphate buffered saline solution showed a high release rate of Ca at the beginning of the test, and a gradual decrease in release rate thereafter to a minimum level until day 7. Similarly, the release rate of Ag in ultra pure water was initially high in the first 4 h and then gradually decreased over a 7 days period. Antibacterial tests have shown a reduction in the viability of S. aureus in Ag-doped coatings particularly in samples with higher Ag concentrations of 3 and 6.5 wt %. Cytotoxicity tests using an osteoblast cell line, on the other hand, have demonstrated that the samples with 6.5 wt % Ag have a negative effect on osteoblast cell response, proliferation, and apoptosis as well as a negative effect on protein and osteocalcin production. It is notable that the samples with 3 wt % Ag or less presented minimal cytotoxicity compared with control surfaces. Considering both the antibacterial and cytotoxicity effects, it is suggested that the 3 wt % of Ag in FGHA coatings can be favorable.

  7. Antibacterial and Antibiofilm Effect of Low Viscosity Chitosan against Staphylococcus epidermidis

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    Inger Sofie Dragland

    2016-01-01

    Full Text Available Aim. The aim of this study was to investigate the antibacterial and antibiofilm properties of low viscosity chitosan on S. epidermidis growth and biofilm formation. Methods and Results. The antibacterial and antibiofilm properties were investigated, during both planktonic growth and biofilm formation. This was performed using different concentrations in media and by coating on polystyrene surfaces. In addition, the bactericidal effect was investigated using a modified direct contact test. The results showed that low viscosity chitosan in media had both a bacteriostatic and bactericidal effect on planktonic growth and biofilm formation of S. epidermidis in a concentration dependent manner. Polystyrene discs coated with chitosan reduced both early biofilm formation (6 h and late biofilm formation (18 h, as confirmed by scanning electron microscopy. The modified direct contact test showed a bactericidal effect. Conclusion. This study demonstrated that low viscosity chitosan has a bacteriostatic and bactericidal activity against S. epidermidis and that the activity is dependent on the amount of chitosan added. In addition, low viscosity chitosan reduced biofilm formation both when added to media and when coated on polystyrene surfaces. Significance and Impact of Study. Low viscosity chitosan could be a contribution to new treatment approaches of biofilm-related infections of S. epidermidis.

  8. Antibacterial Effect of Essential Vegetal Extracts on Staphylococcus aureus Compared to Antibiotics

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    Nicodim Iosif FIT

    2009-11-01

    Full Text Available This study is aiming to evaluate the antimicrobial activity of ten essential vegetal extracts on strains of Staphylococcus aureus isolated from animal lesions. The comparative effect of some antibiotics on these strains isolated from animals was also tested and estimated. The extracts were represented by Albies alba, Aloe barbadensis, Calendula officinalis, Cocos nucifera, Eucalyptus globulus, Hypericum perforatum, Lavandula angustifolia, Satureja hortensis, Mentha piperita, Pinus silvestris essential oils, in three amounts (30 μl, 3 μl and 0,3 μl and comparatively eight antibiotics frequently utilized in staphylococci infections treatment in animals were used. Animal origin S. aureus strains were identified using API staph tests (BioMerieux, France. The tests were realized by diffusion method using Muller Hilton agar while the antibacterial effect was interpreted depending on the inhibition area diameter. The obtained results revealed that Satureja hortensis and Albies alba extracts inhibit the develop of the most staphylococci tested strains. The highest inhibition areas were observed for the amounts of 30 μl and 3 μl essential extract. Most of the staphylococci strains were resistant to antibiotics, the most efficient being Ceftiofur and Methicillin. The results are suggesting that savory and fir has antibacterial effect on S. aureus similar to the best antibiotics proving to be an alternative as natural antibiotics utilization in infectious diseases.

  9. The anti-angiogenic and antibacterial effect ofTinomiscium philippinense Miers. (Menispermaceae) leaf extract

    Institute of Scientific and Technical Information of China (English)

    Sheryl Rena-Aguila; Mario A Tan; Oliver B Villaflores

    2016-01-01

    Objective:To determine the toxicity profile, anti-angiogenic and antibacterial activity of the crude and semi-crude leaf extracts ofTinomiscium philippinense (T. philippinense). Methods:The leaves ofT. philippinense were extracted with methanol and partitioned with solvents of different polarities, namely, hexane, dichloromethane and butanol. The extracts were subjected to duck chorioallantoic membrane assay to establish its anti-angiogenic property. Microwell assay was utilized to determine the minimum inhibitory concentration and minimum bactericidal concentration of the different extracts of the plant. Results:The dichloromethane leaf extract ofT. philippinense at 1 000µg/disc showed the highest anti-angiogenic activity with 37.46% inhibition. All the fractions exhibited a bacteriostatic and bactericidal effect on the three bacterial strains withPseudomonas aeruginosa, a Gram negative lactose fermenter exhibiting a higher sensitivity to dichloromethane semi-crude extract among the treatment groups. For the toxicity test, no mortality and no change in behavior were observed in the Sprague-Dawley rats 14 days after the oral administration of the plant extracts. The methanolic leaf extract ofT. philippinense is non-toxic at a maximum dose of 5 000 mg/kg. Conclusions: The dichloromethane leaf extract ofT. philippinense is a potential anti-angiogenic endemic plant species. This plant extract is also a potential antibacterial candidate as determined by microwell assay. The anti-angiogenic and antibacterial activity of the plant may be attributed to the essential oil, steroid, flavonoid, sterol and triterpene content of the plant.

  10. Evaluation of antibacterial effect of some Sinai medicinal plant extracts on bacteria isolated from bovine mastitis

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    Gamil S. G. Zeedan

    2014-11-01

    for the extracts ranged from 0.01 to 1.56 mg/ml. when comparing antibacterial activity of A. herb alba plant extracted with acetone solvent on the same bacteria with zone of inhibition values ± SD, ranging from 00±00 to 5.6±0.60 mm. Both extracts from J. montana and A. herb alba plant extracts with petroleum ether, methanol and chloroform solvent were less antibacterial activities than acetone solvent extract. Conclusion: The present study spot highlight on isolation and identification of mastitis pathogens that are fundamental aspects of milk quality, udder health control programs and public health and food safety issues associated with food borne pathogens. J. montana and A. herb alba plants have antibacterial effects more than antibiotics used in the treatment of mastitis. Finally, the medicinal plant extracts can be used to discover bioactive natural product in the form of antibacterial that may be serve the development of new pharmaceutical products. But still need further research necessary to identify active compounds and research to mechanism and drug interaction.

  11. 不同培养基对蝉花培养物核苷类成分的影响%Effect of different culture medium on nucleoside component content in culture of Cordyceps cicadae

    Institute of Scientific and Technical Information of China (English)

    张忠亮; 陈桃宝; 尹彬; 崔俏俏; 张霜霜; 王玉芹

    2016-01-01

    目的 建立高效液相色谱(HPLC)法同时检测蝉花培养物4种核苷类成分,分析不同斜面培养基及固体培养基对4种核苷类成分的影响.方法 建立4种核酸类成分——尿苷、鸟苷、腺苷、N6-(2-羟乙基)腺苷的HPLC检测方法,应用Waters Symmetry shield TMRP C18 (250 mm×4.6mm,5μm)色谱柱;流动相为水-甲醇,梯度洗脱;体积流量1.0 mL/min;柱温30℃;进样量10 μL;检测波长260 nm;外标法测定4种核苷类成分水甲.对包括假单胞菌选择培养基(PSA)、沙氏葡萄糖琼脂培养基(SDAY,1 000 mL中含葡萄糖量分别为20、30、40 g)在内的斜面培养基和包括江苏农垦(SCM)、烟农24 (YN-24)、烟农15 (YN-15)、济麦22 (JM-22)在内的固体培养基培养的蝉花培养物中4种核酸类成分水平进行测定,利用SPSS16.0统计软件对测定结果进行多重统计分析,验证并找出引起差异的原因.结果 建立的HPLC法,4种核苷类成分分离度良好,精密度、稳定性、重复性、加样回收率、耐用性均符合要求;4种不同的斜面培养基对尿苷成分基本无影响(P>0.05),PSA对腺苷、鸟苷、N6-(2-羟乙基)腺苷的水平有明显促进作用(P<0.05);固体培养基SCM的4种核苷类成分的水平较高.结论 培养基种类对蝉花培养物核苷类成分变化有直接的影响,确定蝉花虫草的生产工艺时,应充分考虑培养基的选择,同时结合产品成分和生产成本等因素进行综合评价.%Objective The HPLC method was established to simultaneously determine the contents of four kinds of nucleosides in culture of Cordyceps cicadae,and to analyze the effect of different culture medium on nucleoside component content.Methods The HPLC method was applied to determining the contents of four kinds of nucleosides such as uridine,guanosine,adenosine,and N6-(2-hydroxyethyl) adenosine in C.cicadae.Chromatography was carried out on a Waters Symmetry shield TMRP C18 column (250 mm ×4.6 mm,5 μ m) using

  12. Antibacterial Effect of Carboxymethyl Cellulose Coating Enriched by Zataria Multiflora Essential Oil and Grape Seed Extract

    Directory of Open Access Journals (Sweden)

    Raeisi, M.

    2012-01-01

    Full Text Available Background and objectives: The presence of pathogenicbacteria and the factors causing food spoilage are the greatchallenge for public health. Attention to natural additivesinstead of chemical preservatives resulted in conducting severalstudies on plant essential oil and extracts. We aimed atevaluating the antibacterial effect of carboxymethyl cellulosecoating enriched by Zataria multiflora essential oil and grapeseed extract on rainbow trout meat.Material and methods: In this study, two concentrations ofZataria multiflora essential oil (1% and 2% and twoconcentrations of grape seed extract (0.5% and 1% were usedboth alone and in combination with Carboxymethyl cellulosecoating. Antibacterial effect of these treatments was evaluatedby enumeration of bacteria in special culture media.Results: The results obtained in this study demonstrate thatZataria multiflora essential oil in combination with grape seedextract significantly can decrease the number of bacteria anddelay the spoilage of the samples (p<0.05.Conclusion: Coating enriched by Zataria multiflora and grapeseed extract can properly delay the growth of spoilagemicroorganisms and prolong the shelf life of meat products.Key words: Carboxymethyl cellulose coating, Zatariamultiflora essential oil, Grape seed extract, Microbial flora

  13. Antioxidant, antibacterial and in vivo dermal wound healing effects of Opuntia flower extracts.

    Science.gov (United States)

    Ammar, Imene; Bardaa, Sana; Mzid, Massara; Sahnoun, Zouheir; Rebaii, Tarak; Attia, Hamadi; Ennouri, Monia

    2015-11-01

    Opuntia ficus-indica flowers are used for various medicinal purposes. The aims of the present investigation were to evaluate biological properties of O. ficus-indica flowers extracts and to investigate its antioxidant and antibacterial activities and its ability to enhance wound healing. The wound healing activity of the mucilaginous and methanol extracts of O. ficus-indica flowers were assessed using excision wound model in rats. After thirteen days of treatment by both extracts, a beneficial effect on cutaneous repair was observed as assessed by the acceleration of wound contraction and remodeling phases. Histopathological studies of the granulation tissue indicated that the derma is properly arranged with the Opuntia flowers extract, compared with the control group. The mucilage extract was more effective than the methanol extract, but both showed significant results compared with the control. Such investigation was supported by the efficiency of the methanolic and mucilage extract as antimicrobial and antioxidant. Indeed, the extracts showed a potential antioxidant activity determined by different test systems, namely DPPH radicals scavenging activity, trolox equivalent antioxidant capacity, reducing power, β-carotene bleaching assay and metal chelating activity and exhibited significant antibacterial activity against almost all tested bacteria.

  14. In vitro antibacterial effect of different irrigating solutions on Enterococcus faecalis.

    Science.gov (United States)

    Bulacio, María de los Angeles; Cangemi, Rosa; Cecilia, Marta; Raiden, Guillermo

    2006-01-01

    Was evaluated the minimum inhibitory concentration (MIC) and the antibacterial effect (AE) of 2.5% NaOCl, 0.2% chlorhexidine gluconate (CHX) and 17% EDTA on Enterococcus faecalis. The antibacterial capacity was assessed by difusion in agar. The AE was evaluated on contaminated root dentin, employing apical and middle portions of human roots, sterilized and contaminated with Enterococcus faecalis, immersed in the irrigation solutions and incubated at 37 degrees C. Viable cells were counted at 0, 4, 8 and 24 hours. MIC: NaOCl and CHX: 0.2%, EDTA below 5%. Diffusion in agar: NaOCl 2.5% = 21 mm. CHX 0.2% = 14 mm. EDTA 17% = 20 mm. Effect on root dentin: NaOCl 2.5%: Enterococcus faecalis was totally inhibited for 24 hours in the apical area, and for 8 hours in the middle area. CHX 0.2% elicited a reduction of more than 5 log CFU and EDTA 17% induced a reduction of more than 3 log CFU at all the time points examined in the apical and middle areas.

  15. Atomic force microscopy study of the antibacterial effects of chitosans on Escherichia coli and Staphylococcus aureus

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, Peter [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal)], E-mail: peter.eaton@fc.up.pt; Fernandes, Joao C. [Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Rua Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal); Pereira, Eulalia [REQUIMTE, Departamento de Quimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto (Portugal); Pintado, Manuela E.; Xavier Malcata, F. [Escola Superior de Biotecnologia, Universidade Catolica Portuguesa, Rua Dr. Antonio Bernardino de Almeida, 4200-072 Porto (Portugal)

    2008-09-15

    Chitosan has been reported to be a non-toxic, biodegradable antibacterial agent. The aim of this work was to elucidate the relationship between the molecular weight of chitosan and its antimicrobial activity upon two model microorganisms, one Gram-positive (Staphylococcus aureus) and one Gram-negative (Escherichia coli). Atomic force microscopy (AFM) imaging was used to obtain high-resolution images of the effect of chitosans on the bacterial morphology. The AFM measurements were correlated with viable cell numbers, which show that the two species reacted differently to the high- and low-molecular-weight chitosan derivatives. The images obtained revealed not only the antibacterial effects, but also the response strategies used by the bacteria; cell wall collapse and morphological changes reflected cell death, whereas clustering of bacteria appeared to be associated with cell survival. In addition, nanoindentation experiments with the AFM revealed mechanical changes in the bacterial cell wall induced by the treatment. The nanoindentation results suggested that despite little modification observed in the Gram-positive bacteria in morphological studies, cell wall damage had indeed occurred, since cell wall stiffness was reduced after chitooligosaccharide treatment.

  16. Bulk Surfaces Coated with Triangular Silver Nanoplates: Antibacterial Action Based on Silver Release and Photo-Thermal Effect

    Directory of Open Access Journals (Sweden)

    Agnese D’Agostino

    2017-01-01

    Full Text Available A layer of silver nanoplates, specifically synthesized with the desired localized surface plasmon resonance (LSPR features, was grafted on amino-functionalized bulk glass surfaces to impart a double antibacterial action: (i the well-known, long-term antibacterial effect based on the release of Ag+; (ii an “on demand” action which can be switched on by the use of photo-thermal properties of silver nano-objects. Irradiation of these samples with a laser having a wavelength falling into the so called “therapeutic window” of the near infrared region allows the reinforcement, in the timescale of minutes, of the classical antibacterial effect of silver nanoparticles. We demonstrate how using the two actions allows for almost complete elimination of the population of two bacterial strains of representative Gram-positive and Gram-negative bacteria.

  17. Importance of mammalian nuclear-envelope nucleoside triphosphatase in nucleo-cytoplasmic transport of ribonucleoproteins.

    Science.gov (United States)

    Agutter, P S; McCaldin, B; McArdle, H J

    1979-09-15

    The nucleoside triphosphate-stimulated efflux of RNA from isolated nuclei was studied under a range of conditions, and the effects of these conditions on the process were compared with the properties of the nucleoside triphosphatase located in the pore complex. A marked similarity between the rate of efflux and the rate of nucleoside triphosphate hydrolysis was apparent, in terms of substrate specificity, sensitivity to treatment with insolubilized trypsin, kinetics and the effects of increased ionic strength and of many inhibitors. These results are taken, in view of earlier evidence, to suggest that the activity of the nucleoside triphosphatase is a prerequisite for nucleo-cytoplasmic RNA transport in vivo. There are some indications that the nuclear-envelope lipid is also involved in regulating the efflux process.

  18. Novel purine nucleoside analogues for hematological malignancies.

    Science.gov (United States)

    Korycka, Anna; Lech-Marańda, Ewa; Robak, Tadeusz

    2008-06-01

    Recently, the search for more effective and safer antineoplastic agents has led to synthesis and introduction into preclinical and clinical studies of a few new purine nucleoside analogues (PNA). Three of them: clofarabine (CAFdA), nelarabine, and forodesine (immucillin H, BCX-1777), despite belonging to the same group of drugs such as PNA, have shown some differences concerning their active forms, metabolic properties and mechanism of action. However, all these drugs have demonstrated promising activity in patients with relapsed and refractory acute lymphoblastic leukemia (ALL). CAFdA was approved for the therapy of relapsed or refractory ALL in the third line of treatment. It has proved promising in pediatric patients as well as in some patients who are able to proceed to allogenic hematopietic stem cell transplantation (HSCT). Moreover, the drug exhibits an efficacy in acute myeloid leukemia (AML), blast crisis of chronic myelogenous leukemia (CML-BP) and myelodysplastic syndrome (MDS). Nelarabine is recommended for T-ALL and T-cell lymphoblastic lymphoma (T-LBL) with the overall response rates ranging from 11 to 60%. However, the use of the drug is limited by potentially severe neurotoxicity. Forodesine is a purine nucleoside phosphorylase (PNP) inhibitor and it has shown activity in relapsed and refractory T- and B-cells leukemias as well as in cutaneous T-cell lymphoma (CTCL). Recently patented, a few of inventions in the field of pharmaceutical preparation of new PNA have also been published. Great hopes are currently set on the use of these drugs in the treatment of lymphoid and myeloid malignancies in adult and in pediatric patients, however ongoing studies will help to define their role in the standard therapy.

  19. Synergistic antibacterial effects of β-lactam antibiotic combined with silver nanoparticles

    Science.gov (United States)

    Li, Ping; Li, Juan; Wu, Changzhu; Wu, Qingsheng; Li, Jian

    2005-09-01

    The bactericidal action of silver (0) nanoparticles and amoxicillin on Escherichia coli is studied, respectively. Increasing concentration of both amoxicillin (0-0.525 mg ml-1) and silver nanoparticles (0-40 µg ml-1) showed a higher antibacterial effect in Luria-Bertani (LB) medium. Escherichia coli cells have different bactericidal sensitivity to them. When amoxicillin and silver nanoparticles are combined, it results in greater bactericidal efficiency on Escherichia coli cells than when they were applied separately. Dynamic tests on bacterial growth indicated that exponential and stationary phases are greatly decreased and delayed in the synergistic effect of amoxicillin and silver nanoparticles. In addition, the effect induced by a preincubation with silver nanoparticles is examined. The results show that solutions with more silver nanoparticles have better antimicrobial effects. One hypothesized mechanism is proposed to explain this phenomenon.

  20. In vitro and in vivo study of the antibacterial effects of Nigella sativa methanol extract in dairy cow mastitis

    Directory of Open Access Journals (Sweden)

    Hassan Rakhshandeh

    2011-07-01

    Results and conclusion: The extract showed significant in vitro and in vivo inhibitory effects on causative organisms compared to standard drugs and also induced healing of the disease. This is the first veterinary experiment, to our knowledge, that investigated the antibacterial effects of Nigella sativa.

  1. Quercetin-loaded PLGA nanoparticles: a highly effective antibacterial agent in vitro and anti-infection application in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Dongdong; Li, Nuan; Zhang, Weiwei; Yang, Endong; Mou, Zhipeng; Zhao, Zhiwei; Liu, Haiping; Wang, Weiyun, E-mail: weiywswzy@163.com [Anhui Agricultural University, School of Life Sciences (China)

    2016-01-15

    Nanotechnology-based approaches have tremendous potential for enhancing efficacy against infectious diseases. PLGA-based nanoparticles as drug delivery carrier have shown promising potential, owing to their sizes and related unique properties. This article aims to develop nanosized poly (d, l-lactide-co-glycolide) PLGA nanoparticle formulation loaded with quercetin (QT). QT is an antioxidant and antibacterial compound isolated from Chinese traditional medicine with low skin permeability and extreme water insolubility. The quercetin-loaded PLGA nanoparticles (PQTs) were synthesized by emulsion–solvent evaporation method and stabilized by coating with poly (vinyl alcohol). The characteristics of PQTs were analyzed by Fourier transform infrared spectroscopy, Ultraviolet–Visible spectroscopy, scanning electron microscope, transmission electron microscopy, and atomic force microscopy, respectively. The PQTs showed a spherical shape with an average size of 100–150 nm. We compared the antibacterial effects of PQTs against Escherichia coli (E. coli) and Micrococcus tetragenus (M. tetragenus).The PQTs produced stronger antibacterial activity to E. coli than that to M. tetragenus through disrupting bacterial cell wall integrity. The antibacterial ratio was increased with the increasing dosages and incubation time. Next, we tested the in vivo antibacterial activity in mice. No noticeable organ damage was captured from H&E-staining organ slices, suggesting the promise of using PQTs for in vivo applications. The results of this study demonstrated the interaction between bacteria and PLGA-based nanoparticles, providing encouragement for conducting further investigations on properties and antimicrobial activity of the PQTs in clinical application.

  2. Quercetin-loaded PLGA nanoparticles: a highly effective antibacterial agent in vitro and anti-infection application in vivo

    Science.gov (United States)

    Sun, Dongdong; Li, Nuan; Zhang, Weiwei; Yang, Endong; Mou, Zhipeng; Zhao, Zhiwei; Liu, Haiping; Wang, Weiyun

    2016-01-01

    Nanotechnology-based approaches have tremendous potential for enhancing efficacy against infectious diseases. PLGA-based nanoparticles as drug delivery carrier have shown promising potential, owing to their sizes and related unique properties. This article aims to develop nanosized poly ( d, l-lactide-co-glycolide) PLGA nanoparticle formulation loaded with quercetin (QT). QT is an antioxidant and antibacterial compound isolated from Chinese traditional medicine with low skin permeability and extreme water insolubility. The quercetin-loaded PLGA nanoparticles (PQTs) were synthesized by emulsion-solvent evaporation method and stabilized by coating with poly (vinyl alcohol). The characteristics of PQTs were analyzed by Fourier transform infrared spectroscopy, Ultraviolet-Visible spectroscopy, scanning electron microscope, transmission electron microscopy, and atomic force microscopy, respectively. The PQTs showed a spherical shape with an average size of 100-150 nm. We compared the antibacterial effects of PQTs against Escherichia coli ( E. coli) and Micrococcus tetragenus ( M. tetragenus).The PQTs produced stronger antibacterial activity to E. coli than that to M. tetragenus through disrupting bacterial cell wall integrity. The antibacterial ratio was increased with the increasing dosages and incubation time. Next, we tested the in vivo antibacterial activity in mice. No noticeable organ damage was captured from H&E-staining organ slices, suggesting the promise of using PQTs for in vivo applications. The results of this study demonstrated the interaction between bacteria and PLGA-based nanoparticles, providing encouragement for conducting further investigations on properties and antimicrobial activity of the PQTs in clinical application.

  3. Long-term effects of the antibacterial agent triclosan on marine periphyton communities.

    Science.gov (United States)

    Eriksson, K Martin; Johansson, C Henrik; Fihlman, Viktor; Grehn, Alexander; Sanli, Kemal; Andersson, Mats X; Blanck, Hans; Arrhenius, Åsa; Sircar, Triranta; Backhaus, Thomas

    2015-09-01

    Triclosan is a widely used antibacterial agent that has become a ubiquitous contaminant in freshwater, estuary, and marine environments. Concerns about potential adverse effects of triclosan have been described in several recent risk assessments. Its effects on freshwater microbial communities have been well studied, but studies addressing effects on marine microbial communities are scarce. In the present study, the authors describe short- and long-term effects of triclosan on marine periphyton (microbial biofilm) communities. Short-term effects on photosynthesis were estimated after 60 min to 210 min of exposure. Long-term effects on photosynthesis, chlorophyll a fluorescence, pigment content, community tolerance, and bacterial carbon utilization were studied after exposing periphyton for 17 d in flow-through microcosms to 0.316 nM to 10,000 nM triclosan. Results from the short-term studies show that triclosan is toxic to periphyton photosynthesis. Half maximal effective concentration (EC50) values of 1080 nM and 3000 nM were estimated using (14)CO2-incorporation and pulse amplitude modulation (PAM) fluorescence measurements, respectively. After long-term triclosan exposure in flow-through microcosms, photosynthesis estimated using PAM fluorometry was not inhibited by triclosan concentrations up to 1000 nM but instead increased with increasing triclosan concentration. Similarly, at exposure concentrations of 31.6 nM and higher, triclosan caused an increase in photosynthetic pigments. At 316 nM triclosan, the pigment amounts were increased by a factor of 1.4 to 1.9 compared with the control level. Pollution-induced community tolerance was observed for algae and cyanobacteria at 100 nM triclosan and higher. Despite the widespread use of triclosan as an antibacterial agent, the compound did not have any effects on bacterial carbon utilization after long-term exposure.

  4. Nucleoside antibiotics: biosynthesis, regulation, and biotechnology.

    Science.gov (United States)

    Niu, Guoqing; Tan, Huarong

    2015-02-01

    The alarming rise in antibiotic-resistant pathogens has coincided with a decline in the supply of new antibiotics. It is therefore of great importance to find and create new antibiotics. Nucleoside antibiotics are a large family of natural products with diverse biological functions. Their biosynthesis is a complex process through multistep enzymatic reactions and is subject to hierarchical regulation. Genetic and biochemical studies of the biosynthetic machinery have provided the basis for pathway engineering and combinatorial biosynthesis to create new or hybrid nucleoside antibiotics. Dissection of regulatory mechanisms is leading to strategies to increase the titer of bioactive nucleoside antibiotics.

  5. Compositions containing nucleosides and manganese and their uses

    Energy Technology Data Exchange (ETDEWEB)

    Daly, Michael J.; Gaidamakova, Elena K.; Matrosova, Vera Y.; Levine, Rodney L.; Wehr, Nancy B.

    2015-11-17

    This invention encompasses methods of preserving protein function by contacting a protein with a composition comprising one or more purine or pyrimidine nucleosides (such as e.g., adenosine or uridine) and an antioxidant (such as e.g., manganese). In addition, the invention encompasses methods of treating and/or preventing a side effect of radiation exposure and methods of preventing a side effect of radiotherapy comprising administration of a pharmaceutically effective amount of a composition comprising one or more purine or pyrimidine nucleosides (such as e.g., adenosine or uridine) and an antioxidant (such as e.g., manganese) to a subject in need thereof. The compositions may comprise D. radiodurans extracts.

  6. Effect of silver on microstructure and antibacterial property of 2205 duplex stainless steel.

    Science.gov (United States)

    Yang, Sheng-Min; Chen, Yi-Chun; Pan, Yeong-Tsuen; Lin, Dong-Yih

    2016-06-01

    In this study, 2205 duplex stainless steel (DSS) was employed to enhance the antibacterial properties of material through silver doping. The results demonstrated that silver-doped 2205 DSS produces an excellent bacteria-inhibiting effect against Escherichia coli and Staphylococcus aureus. The antibacterial rates were 100% and 99.5%, respectively. Because the mutual solubility of silver and iron is very low in both the solid and liquid states, a silver-rich compound solidified and dispersed at the ferrite/austenite interface and the ferrite, austenite, and secondary austenite phases in silver-doped 2205 DSS. Doping 2205 DSS with silver caused the Creq/Nieq ratio of ferrite to decrease; however, the lower Creq/Nieq ratio promoted the rapid nucleation of γ2-austenite from primary α-ferrite. After 12h of homogenisation treatment at 1200 °C, the solubility of silver in the γ-austenite and α-ferrite phases can be increased by 0.10% and 0.09%, respectively. Moreover, silver doping was found to accelerate the dissolution of secondary austenite in a ferrite matrix during homogenisation.

  7. Introducing a Semi-Coated Model to Investigate Antibacterial Effects of Biocompatible Polymers on Titanium Surfaces

    Science.gov (United States)

    Winkel, Andreas; Dempwolf, Wibke; Gellermann, Eva; Sluszniak, Magdalena; Grade, Sebastian; Heuer, Wieland; Eisenburger, Michael; Menzel, Henning; Stiesch, Meike

    2015-01-01

    Peri-implant infections from bacterial biofilms on artificial surfaces are a common threat to all medical implants. They are a handicap for the patient and can lead to implant failure or even life-threatening complications. New implant surfaces have to be developed to reduce biofilm formation and to improve the long-term prognosis of medical implants. The aim of this study was (1) to develop a new method to test the antibacterial efficacy of implant surfaces by direct surface contact and (2) to elucidate whether an innovative antimicrobial copolymer coating of 4-vinyl-N-hexylpyridinium bromide and dimethyl(2-methacryloyloxyethyl) phosphonate (VP:DMMEP 30:70) on titanium is able to reduce the attachment of bacteria prevalent in peri-implant infections. With a new in vitro model with semi-coated titanium discs, we were able to show a dramatic reduction in the adhesion of various pathogenic bacteria (Streptococcus sanguinis, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis), completely independently of effects caused by soluble materials. In contrast, soft tissue cells (human gingival or dermis fibroblasts) were less affected by the same coating, despite a moderate reduction in initial adhesion of gingival fibroblasts. These data confirm the hypothesis that VP:DMMEP 30:70 is a promising antibacterial copolymer that may be of use in several clinical applications. PMID:25690041

  8. Synergistic Antibacterial Effect of the Combination of ε-Polylysine and Nisin against Enterococcus faecalis.

    Science.gov (United States)

    Liu, Fang; Liu, Mei; Du, Lihui; Wang, Daoying; Geng, Zhiming; Zhang, Muhan; Sun, Chong; Xu, Xiaoxi; Zhu, Yongzhi; Xu, Weimin

    2015-12-01

    This study evaluated the antibacterial effect of the combination of ε-polylysine (ε-PL) and nisin against Enterococcus faecalis strains. The combination of ε-PL and nisin showed synergistic antibacterial activity against three Enterococcus strains. Scanning electron microscopy and a membrane permeability assay revealed that the combined treatment with ε-PL and nisin synergistically damaged the cell morphology of E. faecalis strain R612Z1 cells. Both ε-PL and nisin can dissipate the transmembrane electric potential of E. faecalis R612Z1 cells, but these peptides did not affect the transmembrane pH gradient. The combination of ε-PL and nisin can produce a high reactive oxygen species level in E. faecalis R612Z1 cells. The results indicated that the uptake of ε-PL into cells was promoted through nisin and that the combination of ε-PL and nisin could produce a high reactive oxygen species level in E. faecalis R612Z1 cells, leading to cell growth inhibition.

  9. STUDIES ON ANTIBACTERIAL EFFECT OF APAMARGA (ACHYRANTHES ASPERA ON MULTI-DRUG RESISTANT CLINICAL ISOLATES

    Directory of Open Access Journals (Sweden)

    Patil Usha

    2013-04-01

    Full Text Available Recent reports on emergence of multidrug resistant bacteria are cause of concern in medical world. Several ayurvedic drugs have been proved to contain the antimicrobial activity. Literature on effect of ayurvedic drugs on multidrug resistant bacterial pathogens is limited. Present study reports the antimicrobial effect of Achyranthes aspera (Apamarga crude extracts on the clinical isolates of multidrug resistant bacteria. The drug was evaluated by using phytochemical tests. Crude extracts of aqueous, methanol, ethanol and chloroform was prepared. Antibacterial activity against clinically isolated multidrug resistant bacteria belonging to groups of bacillus, citrobacter, E.coli, klebsiella, proteus and salmonella was tested. The drug showed highest efficacy against Bacillus organism while least effectiveness on Proteus spp bacteria. Results of the study conclude that the medicinal plant A. aspera might be useful against multidrug resistance in pathogens of clinical importance.

  10. Antibacterial Effects of Novel Thiazole Derivatives and the Toxicity of Oxothiazole on Liver Histopathology of Mice

    Directory of Open Access Journals (Sweden)

    Mohsen Najimi

    2015-10-01

    Full Text Available Background and Objectives: Antibiotic resistance in bacteria has actuated researchers toward evaluating many new antibacterial compounds of which are the thiazoles. In this research the inhibitory effects of novel thiazole derivatives were unraveled on Staphylococcus aureus, Streptococcus agalactiae, Pseudomonas aeruginosa and Klebsiella pneumoniae and oxothiazole liver toxicity effects were assessed on mice. Methods: The antibacterial effect of thiazole derivatives was evaluated by measuring the halo zone with disk diffusion method and dilution procedure in microplate in order to discriminate the minimum inhibitory concentration (MIC and the liver toxicity of oxothiazole, also, was discerned by injecting 160 mg/kg, 265 mg/ kg and 350 mg/kg doses to mice as well as scrutinizing the liver histopathology. Results: Derivatives utilized in experiment had no inhibitory effect on Pseudomonas aeruginosa and Klebsiella pneumoniae, though their inhibitory effect was observed on Staphylococcus aureus and Streptococcus agalactiae. For Staphylococcus aureus and Streptococcus agalactiae the diameters of growth inhibition zone were 8.9-22.3 mm and 16.1-25.6 mm, respectively and MIC of 50-200 and 25-100 µg/ml by order. Additionally, by increasing the injection dose of oxothiazole with 160 mg/ml, 265 mg/ml and 350 mg/ml doses, the hepatitis lesions and liver necrosis were observed in experimental mice. Discussion: The thiazole derivatives possessed more inhibitory trace on gram positive bacteria than gram negative ones. Furthermore, the likely presence of oxygen link to thiazole ring in tested compounds results in the enhancement of inhibitory potency of these substances. Besides, our results suggest that high doses of oxothiazole cause severe liver damage and rapid death less than 24 hours.

  11. The in vitro antibacterial effect of S53P4 bioactive glass and gentamicin impregnated polymethylmethacrylate beads.

    Science.gov (United States)

    Gergely, István; Zazgyva, Ancuta; Man, Adrian; Zuh, Sándor György; Pop, Tudor Sorin

    2014-06-01

    Osteomyelitis is a disease that is still difficult to treat, with considerable morbidity and associated costs. The current "gold standard" in treatment - debridement and implantation of antibiotic impregnated polymethylmethacrylate (PMMA) beads - presents the disadvantage of a second surgical intervention required for the removal of the beads. We comparatively investigated the in vitro antibacterial effect of S53P4 bioactive glass (BAG) and gentamicin impregnated PMMA beads. Bacterial viability was assessed hourly by Standard Plate Count during 24 hours of incubation, by determining the number of colony forming units (CFU) of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Klebsiella pneumoniae. Both tested materials showed an antibacterial effect on all studied bacteria. In case of S. aureus, BAG granules were almost as effective as gentamicin impregnated PMMA beads, with no statistically significant differences. In contrast, PMMA beads had a superior antibacterial effect on S. epidermidis and K. pneumoniae. The antibacterial effect of BAG was greatly influenced by granule size and contact time. There was a statistically significant correlation between pH values and the number of CFU in the case of S53P4 BAG granules. As a biocompatible and biodegradable bone substitute, S53P4 bioactive glass can be a good alternative in the local management of osteomyelitis.

  12. Anti-Bacterial effect of Aqueous Garlic Extract (AGE) determined by Disc Diffusion Method against Escherichia coli.

    Science.gov (United States)

    Saha, S; Saha, S K; Hossain, M A; Paul, S K; Gomes, R R; Imtiaz, M; Islam, M M; Nahar, H; Begum, S A; Mirza, T T

    2016-01-01

    The study was performed to determine the antibacterial effect of aqueous extract of garlic (Allium sativum) against standard strain of Escherichia coli ATCC 25922. An interventional study was conducted in Department of Pharmacology and Therapeutics in collaboration with Department of Microbiology, Mymensingh Medical College, Mymensingh. Antibacterial effect of AGE was determined by disc diffusion method. Sensitivity of AGE determined in disc diffusion and the zone of inhibition (ZOI) was 4 mm, 10 mm and 20 mm at 25 μg/10 μl, 50 μg/10 μl and 100 μg/10 μl concentrations respectively. From the findings it is clearly determined the extract has definite antibacterial effect upon Escherichia coli. Further studies are required to detect and isolate the active ingredients present in the Garlic extract as well as detail steps of mechanism responsible for antibacterial effect. Then their effects against the studied organism should be studied in vivo separately and its toxicity profile should also be taken into account.

  13. Synthesis of Nucleoside Derivatives Containing Benzophenoxazinone Moiety

    Institute of Scientific and Technical Information of China (English)

    Yu GAO; Wu Xin ZOU; Ling WU; Jin Shui LI; Ji Tao WANG; Ji Ben MENG

    2004-01-01

    Two new nucleoside derivatives containing benzophenoxazinone moiety were synthesized. Their luminescence spectra show that they have strong near infrared fluorescence. Our study provides a new method for direct introduction of near infrared fluorescent probe to bioactive molecules.

  14. Effect of the existing form of Cu element on the mechanical properties, bio-corrosion and antibacterial properties of Ti-Cu alloys for biomedical application.

    Science.gov (United States)

    Zhang, Erlin; Wang, Xiaoyan; Chen, Mian; Hou, Bing

    2016-12-01

    Ti-Cu alloys have exhibited strong antibacterial ability, but Ti-Cu alloys prepared by different processes showed different antibacterial ability. In order to reveal the controlling mechanism, Ti-Cu alloys with different existing forms of Cu element were prepared in this paper. The effects of the Cu existing form on the microstructure, mechanical, corrosion and antibacterial properties of Ti-Cu alloys have been systematically investigated. Results have shown that the as-cast Ti-Cu alloys showed a higher hardness and mechanical strength as well as a higher antibacterial rate (51-64%) but a relatively lower corrosion resistance than pure titanium. Treatment at 900°C/2h (T4) significantly increased the hardness and the strength, improved the corrosion resistance but had little effect on the antibacterial property. Treatment at 900°C/2h+400°C/12h (T6) increased further the hardness and the mechanical strength, improved the corrosion resistance and but also enhanced the antibacterial rate (>90%) significantly. It was demonstrated that the Cu element in solid solution state showed high strengthening ability but low antibacterial property while Cu element in Ti2Cu phase exhibited strong strengthening ability and strong antibacterial property. Ti2Cu phase played a key role in the antibacterial mechanism. The antibacterial ability of Ti-Cu alloy was strongly proportional to the Cu content and the surface area of Ti2Cu phase. High Cu content and fine Ti2Cu phase would contribute to a high strength and a strong antibacterial ability.

  15. Antibacterial textiles

    NARCIS (Netherlands)

    Bhaskara, Usha Rashmi

    2015-01-01

    The aim of this thesis was the antibacterial functionalization of textiles and its application in professional laundries. The antibacterial functionalization was meant for the various textile packages lent out by the laundry companies to their customers from hotels, hospital or food industries. The

  16. An adenosine nucleoside analogue NITD008 inhibits EV71 proliferation.

    Science.gov (United States)

    Shang, Luqing; Wang, Yaxin; Qing, Jie; Shu, Bo; Cao, Lin; Lou, Zhiyong; Gong, Peng; Sun, Yuna; Yin, Zheng

    2014-12-01

    Enterovirus 71 (EV71), one of the major causative agents of Hand-Foot-Mouth Disease (HFMD), causes severe pandemics and hundreds of deaths in the Asia-Pacific region annually and is an enormous public health threat. However, effective therapeutic antiviral drugs against EV71 are rare. Nucleoside analogues have been successfully used in the clinic for the treatment of various viral infections. We evaluated a total of 27 nucleoside analogues and discovered that an adenosine nucleoside analogue NITD008, which has been reported to be an antiviral reagent that specifically inhibits flaviviruses, effectively suppressed the propagation of different strains of EV71 in RD, 293T and Vero cells with a relatively high selectivity index. Triphosphorylated NITD008 (ppp-NITD008) functions as a chain terminator to directly inhibit the RNA-dependent RNA polymerase activity of EV71, and it does not affect the EV71 VPg uridylylation process. A significant synergistic anti-EV71 effect of NITD008 with rupintrivir (AG7088) (a protease inhibitor) was documented, supporting the potential combination therapy of NITD008 with other inhibitors for the treatment of EV71 infections.

  17. Antibacterial Effect of Aloe Vera Gel against Oral Pathogens: An In-vitro Study

    Science.gov (United States)

    Jain, Supreet; Rathod, Nirav; Sur, Jaideep; Laheji, Afshan; Gupta, Naveen; Agrawal, Priyanka; Prasad, Swati

    2016-01-01

    Introduction Natural herbal remedies have shown promising anti-microbial property and fewer side effects compared to synthetic anti-microbial therapy. Aloe Vera is a medicinal plant used for management of various infections since ancient times as it has anti-inflammatory, anti-microbial, and immune-boosting properties. Aim The aim of the present study was to determine the anti-microbial and inhibitory activities of various concentration of Aloe Vera Gel (AVG) against oral pathogenic bacteria. Materials and Methods Subgingival calculus and aspiration of periapical abscess and periodontal abscess was done in 20 patients and the sample transferred to thioglycolate broth, which was incubated in Mutans Sanguis agar, blood agar and cultured in anaerobic gas chamber. The colonies formed were identified further by gram staining methods and biochemical fermentation tests (IMViC). Each isolated colony of identified bacteria were cultured separately in Muller-Hilton broth and incubated at 37°C for 24 hours. Anti-microbial activity of the AVG was tested by the disc diffusion method and minimum inhibitory concentration was determined by broth micro-dilution method. Result Various staining and biochemical tests confirmed that the sample contained Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), Clostridium bacilli (C. bacilli), Streptcoccus mutans (S. mutans) and Staphlococcus aureus (Staph. aureus). AVG showed anti-bacterial property at 100% and 50% concentration (‘t’ value = 7.504, p-value <0.001). At lower concentration there was no effect against the bacteria. At 100% AVG concentration, zone of inhibition measured was 6.9mm in A. actinomycetemcomitans, 6.3mm in C. bacilli, 6.8mm in S. mutans and 6.6mm in Staph. aureus. The standard drugs were also used to compare anti-bacterial property of AVG. Result showed that higher concentration (100%, 50%) of AVG has comparable zone of inhibition with Ofloxacin (5mcg) and Ciprofloxacin (30mcg). Conclusion AVG at

  18. Nano polyamidoamine-G7 dendrimer synthesis and assessment the antibacterial effect in vitro

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    Mitra Gholami

    2016-04-01

    Full Text Available Background: Nano scale dendrimers are macromolecules synthetic which frequently used in medical and health field. Because traditional antibiotics inevitably induce bacterial resistance, which is responsible for many treatment failures, there is an urgent need to develop novel antibiotic drugs. This study was aimed to examine Synthesis and the antibacterial effect of NanoPolyamidoamine-G7 (NPAMAM-G7 dendrimer on Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus. Methods: In this experimental study that has been conducted in June 2015 in the Laboratory of Microbiology, Iran University of Medical Science, NPAMAM-G7 dendrimers was synthesized by Tomalia’s divergent growth approach. The antibacterial effects of NPAMAM-G7 dendrimer were studied by disc diffusion and micro-dilution method. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC against gram-positive and gram-negative bacteria were determined according to Clinical and Laboratory Standards Institute (CLSI guideline. Standard discs were prepared using different concentrations of dendrimer on Mueller-Hinton agar plates. Results: Zone of inhibition in concentration 25 μg/ml of NPAMAM-G7 dendrimers for Escherichia Coli, Proteus Mirabilis, Salmonella Typhi, Bacillus Subtilis and Staphylococcus Aureus were 26, 38, 36, 22 and 25 mm, respectively. Regarding the zone of inhibition in gram negative bacteria with gram positive ones was P= 0.16 and was not significant difference. The MIC for Salmonella Typhi was 0.025, for Proteus Mirabilis, Bacillus Subtilis, Staphylococcus Aureus and Escherichia Coli was 0.25 μg/ml. The MBC for Salmonella Typhi was 25μg/ml, for Proteus Mirabilis and Bacillus Subtilis was 50 μg/ml and for Escherichia Coli and Staphylococcus Aureus was 100 μg/ml. The least of sensitivity against NPAMAM-G7 related to Escherichia Coli and Staphylococcus Aureus and the most of sensitivity related to

  19. Biogenic silver nanoparticles from Abutilon indicum: their antioxidant, antibacterial and cytotoxic effects in vitro.

    Science.gov (United States)

    Mata, Rani; Nakkala, Jayachandra Reddy; Sadras, Sudha Rani

    2015-04-01

    Green synthesis of silver nanoparticles using biological entities is gaining interest because of their potential applications in nano-medicine. Herein, we report the biological synthesis of Abutilon indicum silver nanoparticles (AIAgNPs) using aqueous Abutilon indicum leaf extract (AILE) and evaluation of their biological applications. TEM analysis revealed that the spherical biogenic AIAgNPs were found to be between 5 and 25 nm in size. The bioactive phyto-constituents such are condensed tannins of AILE were found to play a key role in the reduction and capping of AIAgNPs. The biological properties of AIAgNPs were premeditated as free radical scavenging activity, antibacterial effect and anti-proliferative activity. AIAgNPs were found to exhibit good free radical scavenging activities and the intense zone of inhibition displayed by them in six different pathogenic species indicate the potential antibacterial effect. Further, AIAgNPs showed a dose dependant anti-proliferative effect against COLO 205 (human colon cancer) and MDCK (normal) cells with an IC50 of 3 and 4 μg/mL and 100 and 75 μg/mL, respectively after 24 and 48 h. The morphological changes, chromatin condensation and membrane potential loss induced by AIAgNPs were evidenced by AO/EB and AnnexinV-Cy3 staining. The mitochondrial membrane potential (MMP) loss and G1/S transition cell cycle arrest in COLO 205 cells was evidenced in rhodamine123 staining and FACS analysis. The high levels of ROS as shown in DCF-DA staining could have played a major role in DNA fragmentation and eventually lead to apoptosis. The mode of action through the induction apoptosis by AIAgNPs in COLO 205 cells is exciting with promising application of nano-materials in biomedical research.

  20. In vitro antibacterial effect of aqueous and ethanolic Moringa leaf extracts

    Institute of Scientific and Technical Information of China (English)

    Giselle Cristina Silva; Renata Albuquerque Costa; Antonio Adauto Fonteles Filho

    2011-01-01

    Objective:To evaluate the antibacterial effect of aqueous and ethanolic moringa leaf extracts (Moringa oleifera) on the growth of gram-positive and negative bacteria. Methods:Paper disks were soaked with 100, 200, 300 and 400μL of extract at 20 g/180 mL and 10 g/190 mL. All extracts were tested against Escherichia coli (ATCC25922), Staphylococcus aureus (ATCC25923), Vibrio parahaemolyticus, Enterococcus faecalis (ATCC29212), Pseudomonas aeruginosa (ATCC27853), Salmonella enteritidis (IH) and Aeromonas caviae. The susceptibility tests were performed using the modified disk diffusion method. Results:The strains E. coli, P. aeruginosa and S. enteritidis (IH) were resistant to all treatments. In general, disks with 400μL extract were the most efficient against S. aureus, V. parahaemolyticus, E. faecalis and A. caviae. Conclusions: The study indicates a promising potential for aqueous and ethanolic Moringa leaf extracts as alternative treatment of infections caused by the tested strains.

  1. Synthesis of silver nanoparticles using flavonoids: hesperidin, naringin and diosmin, and their antibacterial effects and cytotoxicity

    Science.gov (United States)

    Sahu, Nidhi; Soni, Deepika; Chandrashekhar, B.; Satpute, D. B.; Saravanadevi, Sivanesan; Sarangi, B. K.; Pandey, R. A.

    2016-07-01

    Three different flavonoids -hesperidin, naringin and diosmin (constituents of citrus plants) were used for the synthesis of silver nanoparticles (AgNPs). Aqueous solutions of pure flavonoids (0.2 mg mL-1) mixed with 1 mM AgNO3 solution were exposed to bright sunlight to prepare the nanoparticles. Characterization of the synthesized nanoparticles by UV-Visible spectrophotometer, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy revealed that the synthesized silver nanoparticles were 10-80 nm in size and polydispersed in nature. Bactericidal effect against common pathogens and cytotoxicity of the synthesized silver nanoparticles was investigated on human promyelocytic leukemic (HL-60) cells. It is concluded that AgNPs synthesized using Naringin as reducing agent showed higher stability and better antibacterial and cytotoxic activities.

  2. Effect of Susceptibility Testing Conditions on the In Vitro Antibacterial Activity of ETX0914.

    Science.gov (United States)

    Giacobbe, Robert A; Huband, Michael D; deJonge, Boudewijn L M; Bradford, Patricia A

    2017-02-01

    The effect of various conditions including pH, inoculum, temperature, atmosphere, divalent cations, and several body fluids on the in vitro activity of the novel antibacterial spiropyrimidinetrione ETX0914 in standard susceptibility tests was investigated against several species. None of the parameters investigated affected the activity of ETX0914, with the exception of pH. Whereas the MIC values for ETX0914 with S. aureus, E. faecalis, and E. coli did not change when the pH of the growth medium was varied from 5 to 8, they did increase at least 8-fold at pH values above 8. This loss of activity can be attributed to the deprotonation of the molecule at elevated pH. The data suggest that routine susceptibility testing with ETX0914 should result in reproducible MIC values.

  3. S-nitrosothiol tethered polymer hexagons: synthesis, characterisation and antibacterial effect.

    Science.gov (United States)

    Priya, S; Nithya, R; Berchmans, Sheela

    2014-01-01

    In this work, we portray a new controlled nitric oxide (NO) delivery platform by grafting S-nitrosothiol derived from cysteine into the polymeric backbone of poly(vinyl methyl ether-co-maleic anhydride). Nitrosothiols (RSNO's) are linked to the polymeric backbone through solvent displacement method. By adjusting solvent polarity, materials of different shapes and sizes varying between μm and nm are prepared. More often our method of preparation resulted in hexagonally shaped polymeric materials. The structure and RSNO conjugation analysis was investigated using scanning electron microscopy (SEM), FT-IR, UV-Vis spectroscopy and thermogravimetric analysis (TGA). Bactericidal efficacy of nitric oxide releasing polymer hexagons, a novel antibacterial agent is demonstrated against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Confocal microscopic studies revealed the enhanced bactericidal effect of polymer hexagons via membrane destruction. Results suggest that this biocompatible NO releasing RSNO conjugated polymer hexagons could be potentially useful for antimicrobial applications.

  4. Antibacterial and antioxidant effects from seaweed, Sargassum wightii (Greville, 1848) against marine ornamental fish pathogens

    Institute of Scientific and Technical Information of China (English)

    Karuppiah Nanthini devi; Thangavel Balasubramanian

    2014-01-01

    Objective: To screen seaweed Sargassum wightii (S. wightii) for bioactive natural substance against marine ornamental fish bacterial pathogens, and also study the antioxidant properties, brine shrimp toxicity effect.Methods:screened for antibacterial activity and purified by column chromatography, purified fractions obtained were tested for the activity. The 1st fraction of acetone extract showed maximum activity, this was again subjected for purification and obtained three sub-fractions also tested for the activity. Total phenols and flavonoid contents, reducing power, free radical scavenging activities (DPPH and H2O2) and brine shrimp toxicity were also studied using purified acetone extract followed by standard methods.Results:Crude extract was made using three solvents (acetone, ethanol and methanol) and ten. GC-MS results revealed two major compounds such as 24-methylene cholesterol (79.9%) and methyl oleate (30.3%) which presented in higher percentage in purified extract and had highest phenols and flavonoid contents, reducing power, free radical scavenging activities, and also showed less toxicity effect. In he present study, the purified extract of S. wightii had potential antibacterial activity against Aeromonas hydrophila [(22.25±0.35) mm] and minimum activity against Streptococcus sp. [(10.00±0.00) mm]. The purified extract of S. wightii also had potential total antioxidant activity of (3.87±0.04) µg at 100 µg/mL concentration and the lowest activity was exhibited (1.52±0.01) µg at 25 µg/mL. The purified acetone extract showed maximum activity against eight pathogens among Conclusions: The present study concluded that the brown seaweed, S. wightii has potential antimicrobial and antioxidant activities, which can be used in aquaculture industry for treated bacterial diseases in infected fishes.

  5. Evaluating the In-vitro Antibacterial Effect of Iranian Propolis on Oral Microorganisms.

    Science.gov (United States)

    Jafarzadeh Kashi, Tahereh Sadat; Kasra Kermanshahi, Ruha; Erfan, Mohammad; Vahid Dastjerdi, Elahe; Rezaei, Yashar; Tabatabaei, Fahimeh Sadat

    2011-01-01

    Propolis has traditionally been used in curing infections and healing wounds and burns. Current researches have shown that propolis has antibacterial, antifungal and antiviral actions however, the pharmacological activity of propolis is highly variable depending on its geographic origin. There have been few studies on the effects of Iranian propolis on the oral microorganisms. In this in-vitro study, the antimicrobial activity of the ethanolic and water extracts of the Iranian propolis (10%, w/v) from north-east area of Tehran was evaluated. Susceptibility of the oral strains tested (Streptococcus mutans ATCC 35668; Streptococcus salivarius ATCC 9222; Staphylococcus aureus ATCC 25923; Enterococcus faecalis ATCC 9854 and Lactobacillus casei ATCC 39392) was evaluated using the agar diffusion method at a concentration of 20 mg/mL of propolis and the zones of growth inhibition were measured. Antibacterial activity was determined by using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) at different concentrations of propolis. The ethanolic extract showed bacteriostatic and bactericidal activity against all the strains, with MIC and MBC ranges of 250-500 µg/mL. The MIC concentration of the water extract was 500 µg/mL against S. mutans and E. faecalis. The water extract showed bactericidal activity only against S. mutans (20 mg/mL). These results indicate that the ethanolic extract is probably more useful in the control of oral biofilms and subsequent dental caries development. However, to determine the consequence of the ethanolic extract of Iranian propolis on the oral mucosa, in-vivo studies of its possible effects are needed.

  6. Effect of surface modification and UVA photoactivation on antibacterial bioactivity of zinc oxide powder

    Science.gov (United States)

    Ann, Ling Chuo; Mahmud, Shahrom; Bakhori, Siti Khadijah Mohd; Sirelkhatim, Amna; Mohamad, Dasmawati; Hasan, Habsah; Seeni, Azman; Rahman, Rosliza Abdul

    2014-02-01

    The effects of surface modification of zinc oxide (ZnO) powder and UVA illumination on the powder towards Escherichia coli and Staphylococcus aureus were investigated. FESEM-EDS results showed that oxygen annealing increased the O:Zn ratio on the surface of ZnO-rod and ZnO-plate samples. Surface conductances of ZnO-rod and ZnO-plate pellets were reduced from 1.05 nS to 0.15 nS and 1.34 nS to 0.23 nS, respectively. Meanwhile, UVA illumination on the surface of the ZnO-rod and ZnO-plate samples was found to improve surface conductance to 7.08 nS and 6.51 nS, respectively, due to the release of charge carrier. Photoluminescence results revealed that oxygen annealing halved the UV emission intensity and green emission intensity, presumably caused by oxygen absorption in the ZnO lattice. The antibacterial results showed that oxygen-treated ZnO exhibited slightly higher growth inhibition on E. coli and S. aureus compared with unannealed ZnO. UVA illumination on ZnO causes the greatest inhibition toward E. coli and S. aureus. Under the UVA excitation, the inhibition of E. coli increased by 18% (ZnO-rod) and 13% (ZnO-plate) while the inhibition of S. aureus increased by 22% (ZnO-rod) and 21% (ZnO-plate). Release of reactive oxygen species were proposed in antibacterial mechanisms, which were aided by surface modification and UVA photoactivation. The reactive oxygen species disrupted the DNA and protein synthesis of the bacterial cell, causing bacteriostatic effects toward E. coli and S. aureus.

  7. Antibacterial effects of Arctium lappa and Artemesia absinthium extracts in laboratory conditions

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    Habibipour Reza

    2015-10-01

    Full Text Available Introduction: Arctium lappa (Great burduck and Artemesia absinthium are medicinal plants that some of their antibacterial and antivirus properties have been suggested in nutritional industries. The objective of this research was to study the effects of A. lappa and A. absinthium on some microorganisms including Pseudomonads aeraginosa, Haemophilus influenza, Bacillus subtilis, Bacillus cereus, Klebsiella pneumonia and Staphylococcus aureus. Methods: Extracts were prepared by maceration method and tested on Mueller Hinton agar medium based on disc diffusion method. The minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were determined by micro-dilution method. Antibiotic disks used for controlling and standardizing the examination. Results: The extracts of A. lappa and A. absinthium had significant effect on S. aureus. The MIC and MBC concentrations of the extract of A. lappa on B. subtilis were respectively 600 and 750 mg/ml. Also, these values were 230 and 540 mg/ml for H. influenza. Extract of A. absinthium showed more inhibitory effect on B. subtilis. All extracts showed inhibitory effect on B. cereus. The extracts of A. lappa and A. absinthium had inhibitory effects on H. influenza and P. aeraginosa. Among antibiotics, only Ofloxacin and Ciprofloxacin had effects on H. influenza. Extract of A. lappa showed flimsy effect on K. pneumonia, while extract of A. absinthium had no effect on this bacterium. Conclusion: Due to the effects of A. lappa and A. absinthium on some bacteria, they might be good substitutes for synthetic substances.

  8. The Molecular Mechanisms of the Antibacterial Effect of Picosecond Laser Generated Silver Nanoparticles and Their Toxicity to Human Cells.

    Science.gov (United States)

    Korshed, Peri; Li, Lin; Liu, Zhu; Wang, Tao

    2016-01-01

    Silver nanoparticles (Ag NPs) are known to have antibacterial properties. They are commonly produced by chemical synthesis which involves the use of harmful reducing agents. Contras, the laser technique is able to generate high-purity Ag NPs in water with specified surface charge characteristics. In the past, the molecular mechanisms contributing to the bactericidal effects of Ag NPs have been investigated extensively, but little is known of the antibacterial and toxic effects and mechanisms involved in laser-generated Ag NPs. In the current study Ag NPs were generated by picosecond laser ablation. Their antibacterial activity was determined on the gram-negative bacteria E. coli and Pseudomonas aeruginosa, and the gram positive bacteria Staphylococcus aureus including the methicillin resistant strain MRSA. Results showed that the laser generated Ag NPs exhibited strong dose-dependent antibacterial activity against all the three bacterial strains tested. Using E.coli as a model system, the laser Ag NPs treatment induced significantly high levels of reactive oxygen species (ROS). These ROS did not include detectable hydroxyl radicals, suggesting for the first time the selective ROS induction in bacterial cells by laser generated Ag NPs. The increased ROS was accompanied by significantly reduced cellular glutathione, and increased lipid peroxidation and permeability, suggesting ROS related bacterial cell damage. The laser generated Ag NPs exhibited low toxicity (within 72 hours) to five types of human cells although a weak significant decrease in cell survival was observed for endothelial cells and the lung cells. We conclude that picosecond laser generated Ag NPs have a broad spectrum of antibacterial effects against microbes including MRSA with minimal human cell toxicity. The oxidative stress is likely the key mechanism underlying the bactericidal effect, which leads to lipid peroxidation, depletion of glutathione, DNA damages and eventual disintegration of the

  9. Effect of copper addition on mechanical properties, corrosion resistance and antibacterial property of 316L stainless steel.

    Science.gov (United States)

    Xi, Tong; Shahzad, M Babar; Xu, Dake; Sun, Ziqing; Zhao, Jinlong; Yang, Chunguang; Qi, Min; Yang, Ke

    2017-02-01

    The effects of addition of different Cu content (0, 2.5 and 3.5wt%) on mechanical properties, corrosion resistance and antibacterial performance of 316L austenitic stainless steel (SS) after solution and aging treatment were investigated by mechanical test, transmission electron microscope (TEM), X-ray diffraction (XRD), electrochemical corrosion, X-ray photoelectron spectroscopy (XPS) and antibacterial test. The results showed that the Cu addition and heat treatment had no obvious influence on the microstructure with complete austenite features. The yield strength (YS) after solution treatment was almost similar, whereas the aging treatment obviously increased the YS due to formation of tiny Cu-rich precipitates. The pitting and protective potential of the solution treated Cu-bearing 316L SS in 0.9wt% NaCl solution increased with increasing Cu content, while gradually declined after aging, owing to the high density Cu-rich precipitation. The antibacterial test proved that higher Cu content and aging were two compulsory processes to exert good antibacterial performance. The XPS results further indicated that aging enhanced the Cu enrichment in passive film, which could effectively stimulate the Cu ions release from the surface of passive film.

  10. SOME RECENT FINDINGS IN THE BIOTECHNOLOGY OF BIOLOGICALLY IMPORTANT NUCLEOSIDES

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    A. Mikhailopulo

    2013-08-01

    Full Text Available Some recent findings in the biotechnology of biologically important nucleosides will be discussed, viz., (i a new strategy of the cascade one-pot transformation of D-pentoses into nucleosides based on the extension and deepening of the knowledge of the mechanism of functioning of the ribokinase, phosphopentomutase, and uridine, thymidine and purine nucleoside (PNP phosphorylases, and the role of different factors (structural, electronic, stereochemical in the glycoside bond formation, (ii the modern chemistries of the chemo-enzymatic syntheses of nucleosides, (iii the transglycosylation reaction using natural and sugar modified nucleosides as donors of carbohydrate residues and heterocyclic bases as acceptors catalyzed by nucleoside phosphorylases (NP.

  11. Blue-violet laser modification of titania treated titanium: antibacterial and osteo-inductive effects.

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    Takanori Kawano

    Full Text Available BACKGROUND: Many studies on surface modifications of titanium have been performed in an attempt to accelerate osseointegration. Recently, anatase titanium dioxide has been found to act as a photocatalyst that expresses antibiotic properties and exhibits hydrophilicity after ultraviolet exposure. A blue-violet semiconductor laser (BV-LD has been developed as near-ultraviolet light. The purpose of this study was to investigate the effects of exposure to this BV-LD on surface modifications of titanium with the goal of enhancing osteoconductive and antibacterial properties. METHODS: The surfaces of pure commercial titanium were polished with #800 waterproof polishing papers and were treated with anatase titania solution. Specimens were exposed using BV-LD (λ = 405 nm or an ultraviolet light-emitting diode (UV-LED, λ = 365 nm at 6 mW/cm(2 for 3 h. The surface modification was evaluated physically and biologically using the following parameters or tests: surface roughness, surface temperature during exposure, X-ray diffraction (XRD analysis, contact angle, methylene blue degradation tests, adherence of Porphyromonas gingivalis, osteoblast and fibroblast proliferation, and histological examination after implantation in rats. RESULTS: No significant changes were found in the surface roughness or XRD profiles after exposure. BV-LD exposure did not raise the surface temperature of titanium. The contact angle was significantly decreased, and methylene blue was significantly degraded. The number of attached P. gingivalis organisms was significantly reduced after BV-LD exposure compared to that in the no exposure group. New bone was observed around exposed specimens in the histological evaluation, and both the bone-to-specimen contact ratio and the new bone area increased significantly in exposed groups. CONCLUSIONS: This study suggested that exposure of titanium to BV-LD can enhance the osteoconductivity of the titanium surface and induce antibacterial

  12. Evaluation of the antibacterial effects of vancomycin hydrochloride released from agar-gelatin-bioactive glass composites.

    Science.gov (United States)

    Rivadeneira, Josefina; Di Virgilio, Ana Laura; Audisio, M Carina; Boccaccini, Aldo R; Gorustovich, Alejandro A

    2015-01-13

    The aim of this work was to evaluate the perfomance of agar-gelatin (AG) composites and AG-containing 45S5 bioactive glass (BG) microparticles (AGBG) in relation to their water uptake capacity, sustained release of a drug over time, and antibacterial effects. The composites were fabricated by the gel-casting method. To impart the local drug release capacity, vancomycin hydrochloride (VC) was loaded in the composites in concentrations of 0.5 and 1 mg ml(-1). VC release was assessed in distilled water at 37 °C up to 72 h and quantified spectrophotometrically. The antibacterial activity of composites was evaluated by the inhibition zone test and the plate count method. The experiments were performed in vitro up to 48 h on three staphylococcus strains: Staphylococcus aureus ATCC29213, S. aureus ATCC6538 and Staphylococcus epidermidis ATCC12228. The results showed that the addition of BG to AG composites did not affect the degree of water uptake. The release of VC was significantly affected by the presence of BG. VC release was higher from AGBGVC films than from AGVC ones over prolonged incubation times. Bacterial inhibition zones were found around the composites. The halos were larger when the cells were put in contact with AGVC composites than when they were put in contact with AGBGVC ones. Nevertheless, the viable count method demonstrated that the composites inhibited Staphylococcus cell growth with no statistical differences. In conclusion, the addition of BG did not reflect an improvement in the parameters studied. On the other hand, composites loaded with VC would have a role in prophylaxis against bacterial infection.

  13. Antibacterial effect of bioactive glass in combination with powdered enamel and dentin

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    Prabhakar A

    2010-01-01

    Full Text Available Background and Objectives: In endodontics, various intracanal medications have been advocated to eliminate bacteria after root canal instrumentation. A recent study has revealed that addition of powdered dentin to bioactive glass (BAG led to increased glass dissolution, and an increased antibacterial efficacy. Therefore, the present study was undertaken to compare the effect of enamel and dentin powder on the antibacterial efficacy of a commercially available BAG. Materials and Methods: Dentin blocks (dbs were prepared from single rooted human teeth. These dbs were infected with Enterococcus faecalis for two weeks in Tryptic Soy Broth (TSB, while negative controls were kept in sterile TSB. In group I, the infected dbs were filled with BAG, in group II with BAG + Enamel powder and group III with BAG + Dentin powder. Dentin samples were harvested from the dbs and cultured. Statistical Analysis: Kruskal-Wallis ANOVA was used for multiple group comparison followed by Scheffe′s post hoc test for pair-wise comparisons. Results: All the combinations of BAG evaluated significantly reduced the bacterial counts compared to the control group. However, at the end of 24 hours, three days, and five days BAG + Dentin powder showed significant reduction ( P < 0.01 in bacterial counts compared to the other experimental groups. Conclusion: Among the various materials evaluated, it appeared that though BAG exhibits antimicrobial efficacy, the addition of powdered enamel and dentin in aqueous suspension definitely enhanced this property. However, the addition of enamel powder BAG did not significantly alter its antimicrobial efficacy compared to BAG + dentin powder.

  14. Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

    Institute of Scientific and Technical Information of China (English)

    Ponmurugan Karuppiah; Shyamkumar Rajaram

    2012-01-01

    Objective: To evaluate the antibacterial properties of Allium sativum (garlic) cloves and Zingiberofficinale (ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection. Methods: The cloves of garlic and rhizomes of ginger were extracted with 95% (v/v) ethanol. The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens. Results: Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates. All the bacterial isolates were susceptible to crude extracts of both plants extracts. Except Enterobacter sp. and Klebsiella sp., all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger. The highest inhibition zone was observed with garlic (19.45 mm) against Pseudomonas aeruginosa (P. aeruginosa). The minimal inhibitory concentration was as low as 67.00 μg/mL against P. aeruginosa. Conclusions: Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.

  15. Modifying effects of boswellia carteri on clarithromycine action: In vitro antibacterial study against common sensitive bacterial strains

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    Hayder M. Al-kuraishy

    2012-09-01

    Full Text Available Background:Plant-derived compounds have action alongside Gram-positive and Gram-negative bacteria and numerous compounds, inhibit efflux pumps and hence have become known as efflux pump inhibitors. Clarithromycin is a macrolide antibiotic used to treat pharyngitis, tonsillitis, acute maxillary sinusitis and acute bacterial exacerbation of chronic bronchitis the antibacterial range is the similar as erythromycin but it is active against Mycobacterium avium complex, M.leprae and atypical mycobacteria. The in vitro antibacterial activity results of different boswellic acid compounds discovered alpha keto-boswellic acid (AKBA to be the preponderance potent antibacterial compound alongside Grampositive pathogens, but it showed no significant antibacterial activity (MIC >128 μg/ml against the Gram negative bacteria . Aim: The aim of present study, is to illustrate the effectiveness of Boswellia carteri against Gram positive and negative bacteria alone and in combination with clarithromycine to elucidate the synergestic antibacterial effects and how Boswellia carteri modifying the antibacterial activity of clarithromycine. Material and methods: The bacteria strains used in this study included five Gram-positive bacteria (Staphylococcus aureus, Streptococcus faecalis, Bacillus cereus, Staphylococcus epidermidis, Staphylococcus saprophyticus and three Gramnegative bacteria (Klebsiella pneumoniae and Escherichia coli and Pseudomonas aeruginosa five for each strains. Antibacterial activities were evaluated by measuring inhibition zone diameters by Agar-well diffusion ,while Broth dilution method determine MIC .Then fractional inhibitory concentration determine the in vitro interaction of clarithromycine and boswellia carteri combination. Results :The result of present study showed that zone of inhibition of clarithromycine ranged from 4mg/ml for Pseudomonas aeruginosa and 19mm toward Klebsiella pneumonia while zone of inhibition of Boswellia carteri

  16. Antibacterial agents in the cinema.

    Science.gov (United States)

    García Sánchez, J E; García Sánchez, E; Merino Marcos, M L

    2006-12-01

    Numerous procedures used as antibacterial therapy are present in many films and include strategies ranging from different antimicrobial drugs to surgery and supporting measures. Films also explore the correct use and misuse of antimicrobial agents. Side effects and other aspects related to antibacterial therapy have also been reflected in some films. This article refers to the presence of antibacterial agents in different popular movies. There are movies in which antibacterial agents form part of the central plot, while in others it is merely an important part of the plot. In still others, its presence is isolated, and in these it plays an ambient or anecdotal role.

  17. In Vitro Antibacterial and Antibiotic Resistance Modifying Effect of Bioactive Plant Extracts on Methicillin-Resistant Staphylococcus epidermidis

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    Romana Chovanová

    2013-01-01

    Full Text Available The crude extracts of plants from Asteraceae and Lamiaceae family and essential oils from Salvia officinalis and Salvia sclarea were studied for their antibacterial as well as antibiotic resistance modifying activity. Using disc diffusion and broth microdilution assays we determined higher antibacterial effect of three Salvia spp. and by evaluating the leakage of 260 nm absorbing material we detected effect of extracts and, namely, of essential oils on the disruption of cytoplasmic membrane. The evaluation of in vitro interactions between plant extracts and oxacillin described in terms of fractional inhibitory concentration (FIC indices revealed synergistic or additive effects of plant extracts and clearly synergistic effects of essential oil from Salvia officinalis with oxacillin in methicillin-resistant Staphylococcus epidermidis.

  18. Comparison of antibacterial effects between antimicrobial peptide and bacteriocins isolated from Lactobacillus plantarum on three common pathogenic bacteria

    OpenAIRE

    Ming, Liu; Zhang, Qian; Yang, Le; Huang, Jian-An

    2015-01-01

    New strategies for the prevention or treatment of infections are required. The purpose of this study is to evaluate the effects of antimicrobial peptides and bacteriocins isolated from Lactobacillus plantarum on growth and biofilm formation of three common pathogenic microbes. The antibacterial properties of the antimicrobial peptide Tet213 and bacteriocins were tested by the disc diffusion method. Tet213 and bacteriocins showed inhibitory effects on biofilm formation for the three organisms,...

  19. Antibacterial and Toxic Effect of Hydrogen Peroxide Combined with Different Concentrations of Chlorhexidine in Comparison with Sodium Hypochlorite

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    Hosein Mirhadi

    2015-12-01

    Full Text Available Statement of the Problem: Hydrogen peroxide (H2O2 has been suggested to be used in sequence or in combination with chlorhexidine (CHX to enhance the antibacterial activity against Enterococcus faecalis, but there is no research in the literature on the safety and effectiveness of this irrigation protocol. Purpose: This study aimed to assess the cytocompatibility and antibacterial activity of different concentrations of CHX combined with H2O2 in comparison with the activity of 5.25 and 2.5% sodium hypochlorite (NaOCl. Materials and Method: Different concentrations of H2O2 (10, 5, 3 and 1% were exposed to the PDL cells. Then, the solution with minimal cytotoxicity was selected (3% H2O2. The cytocompatibility and antibacterial activity of 0.1, 0.2, 1 and 2% CHX combined with 3% H2O2 were evaluated and compared with 5.25 and 2.5% NaOCl. The differences in the mean viability of PDL cells were evaluated by one-way ANOVA. Kruskal-Wallis and post-hoc Dunn's tests were adopted to compare the antibacterial activity of the solutions against E.faecalis. Results: The viability of PDL cells was lower when treated with 5.25 or 2.5% NaOCl than all combinations of CHX and H2O2. There was no significant difference in the antibacterial activity of the solutions against E.faecalis, except for the 0.1% CHX + 3% H2O2 combination, which had significantly lower efficacy than other groups. Conclusion: All combinations of CHX and H2O2 (used in this study except 0.1% CHX + 3% H2O2 were efficient irrigants against planktonic E.faecalis and had a better cytocompatibility with PDL cells than 5.25 and 2.5% NaOCl.

  20. [Effect of pazufloxacin mesilate, a new quinolone antibacterial agent, for intravenous use on QT interval].

    Science.gov (United States)

    Fukuda, Hitoshi; Morita, Yukie; Shiotani, Norio; Mizuo, Midori; Komae, Norihisa

    2004-08-01

    The potential for QT interval prolongation of pazufloxacin mesilate (PZFX mesilate), a new quinolone antibacterial agent for intravenous use, was investigated by in vitro and in vivo electrophysiology studies. Following results were obtained. In vitro electrophysiology study using guinea pig papillary muscles: PZFX mesilate (30-300 microM) had no effects on resting membrane potential (RMP), action potential amplitude (APA) and action potential duration (APD). Reference quinolones, sparfloxacin (3-30 microM) and moxifloxacin (10-100 microM), had no effects on RMP and APA, but significantly prolonged APD at more than 3 and 10 microM, respectively, while ciprofloxacin (10-100 microM) had no effect on each parameter. In vivo electrophysiology study using anesthetized dogs: PZFX mesilate had no effects on electrocardiograph parameter (PR interval, QRS interval, QT interval and QTc) after intravenous administration of 3-30 mg/kg. These results suggest that PZFX mesilate has low potential for QT interval prolongation.

  1. Antibacterial Effect of Curcuma longa (Turmeric) Against Staphylococcus aureus and Escherichia coli.

    Science.gov (United States)

    Afrose, R; Saha, S K; Banu, L A; Ahmed, A U; Shahidullah, A S; Gani, A; Sultana, S; Kabir, M R; Ali, M Y

    2015-07-01

    This observational study was conducted during the period from July 2010 to June 2011 in the Department of Pharmacology in the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh to determine the profile of antibacterial effect of Crude Turmeric paste aqueous turmeric extract, and standard antibiotic Amikacin against Staphylococcus aureus and Escherichia coli. Three separate experiments were done e.g. (Expt- I) Inhibitory effect of Crude Turmeric paste incorporated into nutrient agar (NA) media, (Expt- II) Minimum inhibitory concentration of (a) Aqueous Turmeric extract and (b) Amikacin by broth dilution technique and (Expt-III) their subculture study in nutrient agar (NA) media for confirmation of respective results of previous experiments. Inhibitory effects were observed against the growth of Staph Aureus and Esch coli at 10% and 30% respectively of Crude Turmeric paste incorporated into NA media. The broth dilution technique was followed to determine the MIC of Aqueous Turmeric extract and Amikacin. The MIC of Aqueous Turmeric extract was 800 μg/ml against Staph aureus and that against Esch coli was 2000 μg/ml and the MIC of Amikacin was 10 μg/ml for both the bacteria. The MIC of Amikacin was the lowest in comparison to MIC of Aqueous Turmeric extract for complete inhibition of growth of Staph aureus and Esch coli. The subculture study showed similar results with that of previous experiments in terms of inhibitory effects of Crude Turmeric paste and MIC of Aqueous Turmeric extract and Amikacin against all of the organisms studied.

  2. Improvement of corrosion resistance and antibacterial effect of NiTi orthopedic materials by chitosan and gold nanoparticles

    Science.gov (United States)

    Ahmed, Rasha A.; Fadl-allah, Sahar A.; El-Bagoury, Nader; El-Rab, Sanaa M. F. Gad

    2014-02-01

    Biocomposite consists of gold nanoparticles (AuNPs) and a natural polymer as Chitosan (CS) was electrodeposited over NiTi alloy to improve biocompatibility, biostability, surface corrosion resistance and antibacterial effect for orthopedic implantation. The forming process and surface morphology of this biocomposite coats over NiTi alloy were studied. The results showed that the nm-scale gold particles were embedded in the composite forming compact, thick and smooth coat. Elemental analysis revealed significant less Ni ion release from the coated NiTi alloy compared with the uncoated one by 20 fold. Furthermore, the electrochemical corrosion measurements indicated that AuNPs/CS composite coat was effective for improving corrosion resistance in different immersion times and at all pH values, which suggests that the coated NiTi alloys have potential for orthopedic applications. Additionally, the efficiencies of the biocomposite coats for inhibiting bacterial growth indicate high antibacterial effect.

  3. Antimicrobial evaluation of new synthesized pyridine nucleosides under solvent-free conditions.

    Science.gov (United States)

    Rateb, Nora M; El-Deab, Hany A; Abdou, Ibrahim M

    2013-01-01

    Two series of novel 3-cyano-2-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyloxo) pyridines and 3-cyano-2-(2,3,5-tri-O-acetyl-β-D-ribofuranosyloxy)-4-trifluromethyl-6-phenyl pyridine were synthesized using efficient microwave methods. The targeted compounds were obtained in high yields by reacting 2-(1H)-pyridone or its salt with activated sugars using SiO₂ under solvent-free conditions. Ammonolysis of the resulted acetylated nucleosides produced 3-cyano-2-(β-D-glucopyranosyloxo)-pyridines and 3-cyano-2-(β-D-ribofuranosyloxy)-4-trifluoromethyl-6-phenyl pyridine. These new products were fully characterized using 1D and 2D NMR. These compounds were screened for their antibacterial activities against G(+) and G(-) bacteria and some found to exhibit better antibacterial activities than the control drug.

  4. PHYSICAL PROPERTIES OF ANTIBACTERIAL TREATED COTTON FABRICS AND EFFECT OF LAUNDRY CYCLE

    Directory of Open Access Journals (Sweden)

    PALAMUTCU Sema

    2014-05-01

    Full Text Available During daily usage of textiles, humidity and warmth conditions provide appropriate living conditions for bacteria and microorganisms in textile products. Bacteria growth, infection and cross infection by pathogens might develop due to usage of textile products. Especially since World War II, antibacterial textile products have developed as a result of the hygiene demand of the society. In this study, triclosan (sample A, quaternary ammonium plus triclosan (sample B, dichlorophenol (sample C, silver (sample D, quaternary ammonium (sample E and chitosan (sample F based six different antibacterial additives were applied on 100% cotton fabrics for antibacterial treatment. All six treated fabrics and the untreated fabric (control sample were washed for 40 cycles; the antibacterial efficacies were tested; changes in tear strength and Berger whiteness values of the samples were recorded prior to washing and after 1st, 5th, 10th, 20th and 40th washing cycles. Regarding all washing cycles, a decrease in tear strength results is observed between unwashed and 40 cycle washed samples. Textile materials such as bedlinen, pillow cases, surgeon gowns for which tear strength values are important and that have antibacterial treatments should be tested for tear strength values for different washing cycles to see if they meet minimum tear strength requirements. The change in tear strength and Berger whiteness of samples shows differences according to the antibacterial agent treated and washing cycle applied. Generally, slight decreases in tear strength values are observed. And slight decreases in whiteness, except for sample F which is treated with chitosan, are observed as well. Textile materials having antibacterial treatments should be tested for the special antibacterial agent they are treated and for the number of washing cycles that is required for their product life.

  5. XML Investigating the Phytochemical, Antibacterial and Antifungal Effects of Thymus Vulgaris and Cuminum Cyminum Essential Oils

    Directory of Open Access Journals (Sweden)

    Soghra Valizadeh (MSc

    2016-02-01

    Full Text Available Background and Objective: The aim of this study was to determine the chemical composition, antibacterial and antifungal effects of Thymus vulgaris and Cuminum Cyminum essential oils against foodborne pathogens and Candida species in vitro. Methods: The essential oils were extracted from the aerial parts of Thymus vulgaris and dried Cuminum Cyminum seeds using a Clevenger apparatus for 3 hours. Analysis of the essential oils’ constituents was performed using gas chromatography-mass spectrophotometry. The antibacterial activity of Cuminum Cyminum essential oil and essential oil of Thymus vulgaris against Bacillus cereus, Listeria monocytogenes, Escherichia coli and Salmonella typhimurium were evaluated in agar culture medium. The minimum inhibitory concentration (MIC of these essential oils against fungal strains of Candida albicans, C. tropicalis, C. parapsilosis and C. dubliniensis was measured. Results: Thymol (64.45% and cuminaldehyde (29.02% were the main components of the essential oil of Thymus vulgaris and Cuminum Cyminum, respectively. The largest inhibition zone diameter in the essential oils of Thymus vulgaris and Cuminum Cyminum in the agar disk diffusion method was related to B. cereus with 30 and 21 mm diameter, respectively. The largest growth inhibition zone diameter by the essential oil of Thymus vulgaris in the well diffusion method was 21 mm and against B. cereus. The MIC of essential oil of Thymus vulgaris in the microdilution method was 0.09% against all the four Candida strains. The MIC of Cuminum Cyminum essential oil against strains of C. albicans and C. tropicalis was 0.39%, while it was found as 0.19% against C. parapsilosis and C. dubliniensis. Conclusion: In this study, Cuminum Cyminum essential oil and essential oil of Thymus vulgaris show suitable inhibitory effects against the growth of bacteria using well and disk diffusion methods. Regarding the antifungal effects, the MIC of essential oil of Thymus vulgaris is

  6. Comparative antibacterial effectiveness of alcohol and herbal based commercially available hand antiseptics

    Directory of Open Access Journals (Sweden)

    K Vipin Jain

    2013-01-01

    Full Text Available Background: Human skin is a reservoir of numerous microorganisms. Even though hand washing with soap and water alone reduces the microbial load, the complementary uses of hand antiseptics enhance the antimicrobial effect. Aim: To compare the antimicrobial effectiveness of two commercially available hand antiseptics, routinely used in dental practice, after hand washing with antiseptic soap. Method: A clinical trial with cross over design was carried out on 12 health care workers (HCWs. The antibacterial effectiveness of two hand antiseptics (Alcohol based -Sterillium and Herbal Based-Himalaya′s ′Pure Hands′ compared using fingerprint contact sampling on blood agar. Bacterial samples were obtained before and after hand washing (with antiseptic soap and after hand disinfection. The data was tabulated and analyzed using one way ANOVA and Tukey′s post hoc test for pair-wise comparison. Result: There was a slight decrease in the Colony forming units (CFUs count following use of antiseptic soap when compared to the baseline values. A statistically significant reduction (p<0.000 in the CFUs count was seen following use of both hand antiseptics but the mean number of CFUs reduction was more in case of alcohol based hand antiseptic(sterillium than herbal based hand antiseptic(Himalaya′s ′PureHands". Conclusion: Using alcohol based antiseptic soap before hygienic hand disinfection will provide maximum benefit in reducing the microbial count.

  7. Evaluation of copper ion of antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori and optical, mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Hwan [School of Materials Science and Engineering, University of Yonsei, Seoul (Korea, Republic of); Choi, Yu-ri; Kim, Kwang-Mahn [Department and Research Institute of Dental Biomaterials and Bioengineering, College of Dentistry, University of Yonsei, Seoul (Korea, Republic of); Choi, Se-Young, E-mail: sychoi@yonsei.ac.kr [School of Materials Science and Engineering, University of Yonsei, Seoul (Korea, Republic of)

    2012-02-01

    Antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori of copper ion was researched. Also, additional effects of copper ion coating on optical and mechanical properties were researched as well. Copper ion was coated on glass substrate as a thin film to prevent bacteria from growing. Cupric nitrate was used as precursors for copper ion. The copper ion contained sol was deposited by spin coating process on glass substrate. Then, the deposited substrates were heat treated at the temperature range between 200 Degree-Sign C and 250 Degree-Sign C. The thickness of deposited copper layer on the surface was 63 nm. The antibacterial effect of copper ion coated glass on P. aeruginosa, S. typhimurium and H. pylori demonstrated excellent effect compared with parent glass. Copper ion contained layer on glass showed a similar value of transmittance compared with value of parent glass. The 3-point bending strength and Vickers hardness were 209.2 MPa, 540.9 kg/mm{sup 2} which were about 1.5% and 1.3% higher than the value of parent glass. From these findings, it is clear that copper ion coating on glass substrate showed outstanding effect not only in antibacterial activity but also in optical and mechanical properties as well.

  8. Evaluation of copper ion of antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori and optical, mechanical properties

    Science.gov (United States)

    Kim, Young-Hwan; Choi, Yu-ri; Kim, Kwang-Mahn; Choi, Se-Young

    2012-02-01

    Antibacterial effect on Pseudomonas aeruginosa, Salmonella typhimurium and Helicobacter pylori of copper ion was researched. Also, additional effects of copper ion coating on optical and mechanical properties were researched as well. Copper ion was coated on glass substrate as a thin film to prevent bacteria from growing. Cupric nitrate was used as precursors for copper ion. The copper ion contained sol was deposited by spin coating process on glass substrate. Then, the deposited substrates were heat treated at the temperature range between 200 °C and 250 °C. The thickness of deposited copper layer on the surface was 63 nm. The antibacterial effect of copper ion coated glass on P. aeruginosa, S. typhimurium and H. pylori demonstrated excellent effect compared with parent glass. Copper ion contained layer on glass showed a similar value of transmittance compared with value of parent glass. The 3-point bending strength and Vickers hardness were 209.2 MPa, 540.9 kg/mm2 which were about 1.5% and 1.3% higher than the value of parent glass. From these findings, it is clear that copper ion coating on glass substrate showed outstanding effect not only in antibacterial activity but also in optical and mechanical properties as well.

  9. Amino acid substitutions in HIV-1 reverse transcriptase with corresponding residues from HIV-2. Effect on kinetic constants and inhibition by non-nucleoside analogs.

    Science.gov (United States)

    Bacolla, A; Shih, C K; Rose, J M; Piras, G; Warren, T C; Grygon, C A; Ingraham, R H; Cousins, R C; Greenwood, D J; Richman, D

    1993-08-05

    Nevirapine is a highly potent and specific inhibitor of human immunodeficiency virus type 1 (HIV-1) polymerase, but is inactive against HIV-2 and other polymerase. Previous studies demonstrated that residues 176-190 of HIV-1 reverse transcriptase (RT) can confer nevirapine sensitivity to HIV-2 RT. To better characterize the role of this sequence in HIV-1 RT, we have progressively substituted residues 176-190 of HIV-2 RT for those of HIV-1 RT and monitored the impact on the kinetic properties; inhibitory activity of nevirapine (11-cyclopropyl-5,11-dihydro-4-methyl-6H-dipyrido[2,3-b:2',3'-e] [1,4]diazepin-6-one), E-BPU (5-ethyl-1-benzyloxymethyl-6-(phenylthio)-uracil), and TIBO-R82150 ((+)-S-4,5,6,7-tetrahydro-5-methyl-6-(3-methyl-2-butenyl)imidazo[4,5,1-j k] [1,4]benzodiazepin-2(1H)-thione); and inhibitor-induced fluorescence changes of the mutant enzymes. The study revealed that in addition to Try-181 and Tyr-188, a new amino acid residue (Gly-190) plays an important role in determining susceptibility to nevirapine and E-BPU, but not to TIBO-R82150. These data argue that these non-nucleoside inhibitors fit differently, even though they share a common binding pocket. Nevirapine was seen to exert inhibitory activity by altering the interaction of the enzyme with the template-primer. Kinetic parameters were modulated by the template (DNA versus RNA) as well as by some of the mutations.

  10. Synergistic Antibacterial Effect of Silver Nanoparticles Combined with Ineffective Antibiotics on Drug Resistant Salmonella typhimurium DT104.

    Science.gov (United States)

    McShan, Danielle; Zhang, Ying; Deng, Hua; Ray, Paresh C; Yu, Hongtao

    2015-01-01

    Synergistic antibacterial activity of combined silver nanoparticles (AgNPs) with tetracycline (polykeptide), neomycin (aminoglycoside), and penicillin (β-lactam) was tested against the multidrug resistant bacterium Salmonella typhimurium DT104. Dose-dependent inhibition of Salmonella typhimurium DT104 growth is observed for tetracycline-AgNPs and neomycin-AgNPs combination with IC50 of 0.07 μg/mL and 0.43 μg/mL, respectively. There is no inhibition by the penicillin-AgNPs combination. These results suggest that the combination of the ineffective tetracycline or neomycin with AgNPs effectively inhibits the growth of this bacterium. The synergistic antibacterial effect is likely due to enhanced bacterial binding by AgNPs assisted by tetracycline or neomycin, but not by penicillin.

  11. Antibacterial effects of protruding and recessed shark skin micropatterned surfaces of polyacrylate plate with a shallow groove.

    Science.gov (United States)

    Sakamoto, Akihiko; Terui, Yusuke; Horie, Chihiro; Fukui, Takashi; Masuzawa, Toshiyuki; Sugawara, Shintaro; Shigeta, Kaku; Shigeta, Tatsuo; Igarashi, Kazuei; Kashiwagi, Keiko

    2014-12-01

    Antibacterial effects in terms of biofilm formation and swarming motility were studied using polyacrylate plates having protruding or recessed shark skin micropatterned surfaces with a shallow groove (2 μm pattern width and spacing, 0.4 μm pattern height). It was found that biofilm formation and swarming motility of Pseudomonas aeruginosa were strongly inhibited by the shark skin pattern plates with a shallow (0.4 μm) pattern height. Biofilm formation of Staphylococcus aureus was also strongly inhibited. Live bacteria were located on the pattern rather than in the spacing. When the shape of pattern was a linear ridge instead of shark skin, the antibacterial effects were weaker than seen with the shark skin pattern. The results indicate that the pattern of shark skin is important for decreasing bacterial infection even with a shallow feature height.

  12. Photocatalytic antibacterial effects on TiO2-anatase upon UV-A and UV-A/VIS threshold irradiation.

    Science.gov (United States)

    Wu, Yanyun; Geis-Gerstorfer, Jürgen; Scheideler, Lutz; Rupp, Frank

    2016-01-01

    Photocatalysis mediated by the anatase modification of titanium dioxide (TiO2) has shown antibacterial effects in medical applications. The aim of this study was to investigate the possibility of expanding the excitation wavelengths for photocatalytic antibacterial effects from ultraviolet (UV) into the visible light range. After deposition of salivary pellicle and adhesion of Streptococcus gordonii on anatase, different irradiation protocols were applied to induce photocatalysis: ultraviolet A (UV-A) > 320 nm; ultraviolet/visible (UV-A/VIS) light > 380 nm and > 390 nm; and VIS light 400-410 nm. A quartz crystal microbalance with dissipation (QCM-D) tests and microscopic examination were used to observe the photoinduced antibacterial effects. Salivary pellicle could be photocatalytically decomposed under all irradiation protocols. In contrast, effective photocatalytic attack of bacteria could be observed by UV-A as well as by UV-A/VIS at 380 nm < λ < 390 nm only. Wavelengths above 380 nm show promise for in situ therapeutic antifouling applications.

  13. Radiographic, antibacterial and bond-strength effects of radiopaque caries tagging.

    Science.gov (United States)

    Umwali, Aurore; Askar, Haitham; Paris, Sebastian; Schwendicke, Falk

    2016-06-02

    Selectively excavated carious lesions remain radiographically detectable. Radiopaque tagging could resolve the resulting diagnostic uncertainty. We aimed to evaluate if tagging depends on lesions depths, is antibacterial, or affects dentin bond-strengths. Artificial lesions (depth-range: 152-682 μm, n = 34/group) were induced in human dentin samples, evaluated using wavelength-independent microradiography, treated with one of two tagging materials (70% SnCl2, 30% SnF2) and re-evaluated. To evaluate antimicrobial effects, 40 dentin samples were submitted to a Lactobacillus rhamnosus invasion-model. Infected samples were treated with placebo, 0.2% chlorhexidine, SnCl2, SnF2 (n = 10/group). Dentin was sampled and colony-forming units/mg determined. Micro-tensile bond-strengths of adhesive restorations (OptiBond FL, Filtek Z250) to tagged or untagged, sound and carious dentin were assessed (n = 12/group). Tagged surfaces were evaluated microscopically and via energy-dispersive X-ray-spectroscopy (EDS). Tagging effects of both materials decreased with increasing lesion depths (p bond strengths (p < 0.001) on sound (-22%/-33% for SnCl2/SnF2) and carious dentin (-50%/-54%). This might be due to widespread tin chloride or fluoride precipitation, as detected via microscopy and EDS. While radiopaque tagging seems beneficial, an optimized application protocol needs to be developed prior clinical use.

  14. Antibacterial Studies and Effect of Poloxamer on Gold Nanoparticles by Zingiber Officinale Extracted Green Synthesis.

    Science.gov (United States)

    Chitra, K; Reena, K; Manikandan, A; Antony, S Arul

    2015-07-01

    Poloxamer finds excellent clinical and therapeutic uses for curing of various ailments. The Zin- giber officinale (Z. officinale) is one of the well-known medicinal plants. The poloxamer188 and the rhizome extract of Z. officinale have been used to synthesize the gold nanoparticles (AuNPs) by a green approach. The Z. officinale extract has been used as a reducing agent while the polox- amerl88 has been used as a stabilizing agent. The effect of addition of poloxamer on the controlling the shape and size of the AuNPs has been investigated by transmission electron microscopy (TEM) and dynamic light scattering techniques. The formation of AuNPs has also been confirmed by UV-Visible spectral, energy dispersive X-ray (EDX) and powder X-ray diffraction (XRD) analyses. The anti-bacterial activity of the green synthesized AuNPs has been investigated on the three human pathogens Staphylococcus aureus, Escherichia coli, and Klebsiella pneumonia. The poloxamer188 protected AuNPs inhibit the bacterial growth more effectively than the pure Z. officinale extract and the standard tetracycline (TA).

  15. 常用食品防腐剂的抑菌效果%Antibacterial Effect of Commonly Used Food Preservatives

    Institute of Scientific and Technical Information of China (English)

    胡春红; 乔琳; 古红梅; 李季平; 杨潇

    2013-01-01

    取一定量大肠杆菌和金黄色葡萄球菌菌悬液分别接种在含不同质量浓度的苯甲酸钠和山梨酸钾的液体培养基中培养18h,然后测定OD值,研究两种防腐剂对大肠杆菌和金黄色葡萄球菌的抑菌效果.结果表明,防腐剂苯甲酸钠(≥0.2 g/L)和山梨酸钾(≥0.3 g/L)对两种菌的生长都呈显著的抑制作用,且随浓度增加抑菌作用逐渐增强;相同浓度下苯甲酸钠的抑菌效果要好于山梨酸钾.%In order to study the antibacterial effect of Sodium Benzoate and Potassium Sorbate on E. coli and Staphylococcus aureus. Certain density bacterial suspension was added into the liquid culture medium included of different concentration of Sodium Benzoate and Potassium Sorbate to cultivate for 18 hours, and then the values of OD determined. The results showed that Sodium Benzoate (≥0.2g/L) and Potassium Sorbate (≥0.3g/L) had significant antibacterial effect on the two bacteria. The antibacterial effect gradually increased along with the increasing of concentration of Sodium Benzoate and Potassium Sorbate; The antibacterial effect of Sodium Benzoate was better than Potassium Sorbate at the same concentration.

  16. Osteogenic activity and antibacterial effect of zinc oxide/carboxylated graphene oxide nanocomposites: Preparation and in vitro evaluation.

    Science.gov (United States)

    Chen, Junyu; Zhang, Xin; Cai, He; Chen, Zhiqiang; Wang, Tong; Jia, Lingling; Wang, Jian; Wan, Qianbing; Pei, Xibo

    2016-11-01

    The aim of this study was to prepare nanocomposites of carboxylated graphene oxide (GO-COOH) sheets decorated with zinc oxide (ZnO) nanoparticles (NPs) and investigate their advantages in the field of bone tissue engineering. First, ZnO/GO-COOH nanocomposites were synthesized by facile reactions, including the carboxylation of graphene oxide (GO) and the nucleation of ZnO on GO-COOH sheets. The synthesized ZnO/GO-COOH nanocomposites were then characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectra, and transmission electron microscopy (TEM). The biocompatibility, osteogenic activity and antibacterial effect of ZnO/GO-COOH nanocomposites were further investigated. In the nanocomposites, ZnO nanoparticles with a size of approximately 12nm were uniformly decorated on GO-COOH sheets. Compared with GO-COOH and the control group, ZnO/GO-COOH nanocomposites significantly enhanced ALP activity, osteocalcin production and extracellular matrix mineralization as well as up-regulated osteogenic-related genes (ALP, OCN, and Runx2) in MG63 osteoblast-like cells. Moreover, ZnO/GO-COOH nanocomposites had an antibacterial effect against Streptococcus mutans. These results indicated that ZnO/GO-COOH nanocomposites exhibited both osteogenic activity and antibacterial effect and had great potential for designing new biomaterials in the field of bone tissue engineering.

  17. An in vitro study on the effects of nisin on the antibacterial activities of 18 antibiotics against Enterococcus faecalis.

    Science.gov (United States)

    Tong, Zhongchun; Zhang, Yuejiao; Ling, Junqi; Ma, Jinglei; Huang, Lijia; Zhang, Luodan

    2014-01-01

    Enterococcus faecalis rank among the leading causes of nosocomial infections worldwide and possesses both intrinsic and acquired resistance to a variety of antibiotics. Development of new antibiotics is limited, and pathogens continually generate new antibiotic resistance. Many researchers aim to identify strategies to effectively kill this drug-resistant pathogen. Here, we evaluated the effect of the antimicrobial peptide nisin on the antibacterial activities of 18 antibiotics against E. faecalis. The MIC and MBC results showed that the antibacterial activities of 18 antibiotics against E. faecalis OG1RF, ATCC 29212, and strain E were significantly improved in the presence of 200 U/ml nisin. Statistically significant differences were observed between the results with and without 200 U/ml nisin at the same concentrations of penicillin or chloramphenicol (pnisin and penicillin or chloramphenicol had a synergetic effect against the three tested E. faecalis strains. The transmission electron microscope images showed that E. faecalis was not obviously destroyed by penicillin or chloramphenicol alone but was severely disrupted by either antibiotic in combination with nisin. Furthermore, assessing biofilms by a confocal laser scanning microscope showed that penicillin, ciprofloxacin, and chloramphenicol all showed stronger antibiofilm actions in combination with nisin than when these antibiotics were administered alone. Therefore, nisin can significantly improve the antibacterial and antibiofilm activities of many antibiotics, and certain antibiotics in combination with nisin have considerable potential for use as inhibitors of this drug-resistant pathogen.

  18. Antibacterial effect of gallium and silver on Pseudomonas aeruginosa treated with gallium-silver-phosphate-based glasses.

    Science.gov (United States)

    Valappil, Sabeel P; Higham, Susan M

    2014-01-01

    Gallium and silver incorporated phosphate-based glasses were evaluated for antibacterial effect on the growth of Pseudomonas aeruginosa, which is a leading cause of opportunistic infections. The glasses were produced by conventional melt quenching methods at 1100°C for 1 h. Glass degradation studies were conducted by weight loss method. Disc diffusion assay and cell viability assay displayed statistically significant (p ≤ 0.0005) effect on P. aeruginosa growth which increased with decreasing calcium content in the glasses. The gallium ion release rates (1.83, 0.69 and 0.48 ppm·h(-1)) and silver ion release rates (2.97, 2.84 and 2.47 ppm·h(-1)) were found to account for this variation. Constant depth film fermentor was used to evaluate the anti-biofilm properties of the glasses. Both gallium and silver in the glass contributed to biofilm growth inhibitory effect on P. aeruginosa (up to 2.68 reduction in log 10 values of the viable counts compared with controls). The glasses were found to deliver gallium and silver in a controlled way and exerted cumulative antibacterial action on planktonic and biofilm growth of P. aeruginosa. The antibacterial, especially anti-biofilm, properties of the gallium and silver incorporated phosphate-based glasses make them a potential candidate to combat infections caused by P. aeruginosa.

  19. Antibacterial Effect of Myrtus Communis Hydro-Alcoholic Extract on Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    Ali Taheri

    2013-06-01

    Full Text Available Background: Today, due to the changes in the form of the resistance of pathogenic bacteria, discovering new antimicrobial drugs is under study. So, the aim of this study is to evaluate the antimicrobial properties of the extract of the myrtle herb on some of pathogenic bacteria. Materials and Methods: Hydroalcoholic extract of the leaves of myrtle herb was evaluated at 4 concentrations including 10-80 mg/ml on four strains of pathogenic bacteria using penetrative dissemination method together with the measuring diameter of the growth inhibition zone; then the results were compared to four conventional antibiotics. The minimum inhibitory and bactericidal concentrations were studied using macro dilution method. Results: Treatment by the concentration of 80 mg/ml extract of this herb showed the greatest effect on the bacterium Staphylococcus aureus and Vibrio cholera serotype Ogawa which had a significant difference with all other treatments and standard antibiotics (p> 0.05. The extract showed no effect on the bacterium Pseudomonas aeruginosa and just concentration of 80 mg/ml showed a little effect on E. coli and other antibiotics had no significant effect except tetracycline which has little effect on this strain. Minimum inhibitory concentration was 0.2 mg/ml for bacterium Staphylococcus aureus (S. aureus and the maximum for E.coli by 8 mg/ml.Conclusion: This study showed that under study bacteria were more resistant to the antibiotics and the extract of Myrtus communis leaves showed greatest antibacterial effect against S. aureus and V. cholerae cerotype Ogawa.

  20. Apoplastic Nucleoside Accumulation in Arabidopsis Leads to Reduced Photosynthetic Performance and Increased Susceptibility Against Botrytis cinerea.

    Science.gov (United States)

    Daumann, Manuel; Fischer, Marietta; Niopek-Witz, Sandra; Girke, Christopher; Möhlmann, Torsten

    2015-01-01

    Interactions between plant and pathogen often occur in the extracellular space and especially nucleotides like ATP and NAD have been identified as key players in this scenario. Arabidopsis mutants accumulating nucleosides in the extracellular space were generated and studied with respect to susceptibility against Botrytis cinerea infection and general plant fitness determined as photosynthetic performance. The mutants used are deficient in the main nucleoside uptake system ENT3 and the extracellular nucleoside hydrolase NSH3. When grown on soil but not in hydroponic culture, these plants markedly accumulate adenosine and uridine in leaves. This nucleoside accumulation was accompanied by reduced photosystem II efficiency and altered expression of photosynthesis related genes. Moreover, a higher susceptibility toward Botrytis cinerea infection and a reduced induction of pathogen related genes PR1 and WRKY33 was observed. All these effects did not occur in hydroponically grown plants substantiating a contribution of extracellular nucleosides to these effects. Whether reduced general plant fitness, altered pathogen response capability or more direct interactions with the pathogen are responsible for these observations is discussed.

  1. Apoplastic nucleoside accumulation in Arabidopsis leads to reduced photosynthetic performance and increased susceptibility against Botrytis cinerea

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    Manuel eDaumann

    2015-12-01

    Full Text Available ABSTRACT Interactions between plant and pathogen often occur in the extracellular space and especially nucleotides like ATP and NAD have been identified as key players in this scenario. Arabidopsis mutants accumulating nucleosides in the extracellular space were generated and studied with respect to susceptibility against Botrytis cinerea infection and general plant fitness determined as photosynthetic performance. The mutants used are deficient in the main nucleoside uptake system ENT3 and the extracellular nucleoside hydrolase NSH3. When grown on soil but not in hydroponic culture, these plants markedly accumulate adenosine and uridine in leaves. This nucleoside accumulation was accpmpanied by reduced photosystem II efficiency and altered expression of photosynthesis related genes. Moreover, a higher susceptibility towards Botrytis cinerea infection and a reduced induction of pathogen related genes PR1 and WRKY33 was observed. All these effects did not occur in hydroponically grown plants substantiating a contribution of extracellular nucleosides to these effects. Whether reduced general plant fitness, altered pathogen response capability or more direct interactions with the pathogen are responsible for these observations is discussed.

  2. Antibacterial, Antibiofilm Effect of Burdock (Arctium lappa L.) Leaf Fraction and Its Efficiency in Meat Preservation.

    Science.gov (United States)

    Lou, Zaixiang; Li, Cheng; Kou, Xingran; Yu, Fuhao; Wang, Hongxin; Smith, Gary M; Zhu, Song

    2016-08-01

    First, the antibacterial, antibiofilm effect and chemical composition of burdock (Arctium lappa L.) leaf fractions were studied. Then, the efficiency of burdock leaf fractions in pork preservation was evaluated. The results showed that burdock leaf fraction significantly inhibited the growth and biofilm development of Escherichia coli and Salmonella Typhimurium. MICs of burdock leaf fractions on E. coli and Salmonella Typhimurium were both 2 mg/ml. At a concentration of 2.0 mg/ml, the inhibition rates of the fraction on growth and development of E. coli and Salmonella Typhimurium biofilms were 78.7 and 69.9%, respectively. During storage, the log CFU per gram of meat samples treated with burdock leaf fractions decreased 2.15, compared with the samples without treatment. The shelf life of pork treated with burdock leaf fractions was extended 6 days compared with the pork without treatment, and the sensory property was obviously improved. Compared with the control group, burdock leaf fraction treatment significantly decreased the total volatile basic nitrogen value and pH of the meat samples. Chemical composition analysis showed that the burdock leaf fraction consisted of chlorogenic acid, caffeic acid, p-coumaric acid, rutin, cynarin, crocin, luteolin, arctiin, and quercetin. As a vegetable with an abundant source, burdock leaf is safe, affordable, and efficient in meat preservation, indicating that burdock leaf fraction is a promising natural preservative for pork.

  3. Green Synthesis and Antibacterial Effect of Silver Nanoparticles Using Vitex Negundo L.

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    Fatima Abu Bakar

    2011-08-01

    Full Text Available Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs due to their multiple applications. One of the most important applications of Ag-NPs is their use as an anti-bacterial agent. The use of plants in the synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the biosynthesis of silver nanoparticles using Vitex negundo L. extract and its antimicrobial properties has been reported. The resulting silver particles are characterized using transmission electron microscopy (TEM, X-ray diffraction (XRD and UV–Visible (UV-Vis spectroscopic techniques. The TEM study showed the formation of silver nanoparticles in the 10–30 nm range and average 18.2 nm in size. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc structure. The silver nanoparticles showed the antimicrobial activity against Gram positive and Gram negative bacteria. Vitex negundo L. was found to display strong potential for the synthesis of silver nanoparticles as antimicrobial agents by rapid reduction of silver ions (Ag+ to Ag0.

  4. Photoinduced green synthesis of silver nanoparticles with highly effective antibacterial and hydrogen peroxide sensing properties.

    Science.gov (United States)

    Kumar, Vijay; Gundampati, Ravi Kumar; Singh, Devendra K; Bano, Daraksha; Jagannadham, Medicherla V; Hasan, Syed Hadi

    2016-09-01

    In this study, an eco-friendly and sustainable green route was employed for the synthesis of stable silver nanoparticles (AgNPs) using aqueous leaf extract of Euphorbia hirta (AEE) as both reducing as well as a stabilizing agent. The synthesis of AgNPs was confirmed by UV-visible spectroscopy which produced a prominent SPR band at λmax 425nm after 25min of sunlight exposure. The AgNPs thus synthesized were optimized using one factor at a time approach, and these optimized conditions were 25min of sunlight exposure time, 5.0% (v/v) of AEE inoculum dose and 3.0mM of AgNO3 concentration. The Field Emission Scanning Electron Microscopy (FE-SEM) and High Resolution Transmission Electron Microscopy (HRTEM) analysis confirmed the presence of spherical AgNPs with average size 15.5nm. The crystallinity was determined by X-ray Diffractometer (XRD) and Selected Area Electron Diffraction (SAED) pattern. Chemical and elemental compositions were determined by Fourier Transformed Infrared Spectroscopy (FTIR) and Energy Dispersive X-ray Spectroscopy (EDX) respectively. The Atomic Force Microscopy (AFM) images with average roughness 1.15nm represented the lateral and 3D topological characteristic of AgNPs. The AgNPs thus synthesized showed effective antibacterial activity against gram negative and gram positive bacteria as well as hydrogen peroxide sensing property with a minimum detection limit of 10(-7)M.

  5. The potential of use basil and rosemary essential oils as effective antibacterial agents.

    Science.gov (United States)

    Sienkiewicz, Monika; Łysakowska, Monika; Pastuszka, Marta; Bienias, Wojciech; Kowalczyk, Edward

    2013-08-05

    The considerable therapeutical problems of persistent infections caused by multidrug-resistant bacterial strains constitute a continuing need to find effective antimicrobial agents. The aim of this study was to demonstrate the activities of basil (Ocimum basilicum L.) and rosemary (Rosmarinus officinalis L.) essential oils against multidrug- resistant clinical strains of Escherichia coli. A detailed analysis was performed of the resistance of the drug to the strains and their sensitivity to the tested oils. The antibacterial activity of the oils was tested against standard strain Escherichia coli ATCC 25922 as well as 60 other clinical strains of Escherichia coli. The clinical strains were obtained from patients with infections of the respiratory tract, abdominal cavity, urinary tract, skin and from hospital equipment. The inhibition of microbial growth by both essential oils, presented as MIC values, were determined by agar dilution. Susceptibility testing to antibiotics was carried out using disc diffusion. The results showed that both tested essential oils are active against all of the clinical strains from Escherichia coli including extended-spectrum β-lactamase positive bacteria, but basil oil possesses a higher ability to inhibit growth. These studies may hasten the application of essential oils in the treatment and prevention of emergent resistant strains in nosocomial infections.

  6. ANTIBACTERIAL EFFECT OF LEMONGRASS OIL ON ORAL MICROORGANISMS: AN IN VITRO STUDY

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    Ruchika Goyal

    2013-04-01

    Full Text Available Aim of the study was to know antibacterial effect of lemongrass oil on oral microorganisms: Streptococcus mutans, Prevotella intermedia and Porphyromonas gingivalis. The disc diffusion test for the Streptococcus mutans, was carried out at various concentrations of lemongrass oil as neat, 1:2, 1:5, 1:10, 1:20 and 1: 25. The punch hole diffusion technique was used for Prevotella intermedia and Porhyromonas gingivalis at various concentrations of lemongrass oil as neat, 1:2, 1:5, 1:10, 1:20 and 1:25. The disc diffusion test for Streptococcus mutans showed the zone of inhibition of >40mm, >40mm, >20mm, 14mm,14mm at the concentration of neat, 1:2, 1:5, 1:10, 1:20 respectively. The punch hole diffusion technique used for Prevotella intermedia and Porhyromonas gingivalis showed Zone of inhibition of >30mm, >20mm, >10mm at the concentrations of neat, 1:2, 1:5, and 1:10 respectively. The study has demonstrated that essential oil of lemongrass has significant antimicrobial potential against oral microorganisms S.mutans, P. intermedia and P. gingivalis.

  7. Biotechnological Screening of Microalgal and Cyanobacterial Strains for Biogas Production and Antibacterial and Antifungal Effects

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    Opayi Mudimu

    2014-05-01

    Full Text Available Microalgae and cyanobacteria represent a valuable natural resource for the generation of a large variety of chemical substances that are of interest for medical research, can be used as additives in cosmetics and food production, or as an energy source in biogas plants. The variety of potential agents and the use of microalgae and cyanobacteria biomass for the production of these substances are little investigated and not exploited for the market. Due to the enormous biodiversity of microalgae and cyanobacteria, they hold great promise for novel products. In this study, we investigated a large number of microalgal and cyanobacterial strains from the Culture Collection of Algae at Göttingen University (SAG with regard to their biomass and biogas production, as well antibacterial and antifungal effects. Our results demonstrated that microalgae and cyanobacteria are able to generate a large number of economically-interesting substances in different quantities dependent on strain type. The distribution and quantity of some of these components were found to reflect phylogenetic relationships at the level of classes. In addition, between closely related species and even among multiple isolates of the same species, the productivity may be rather variable.

  8. Antibacterial Effect of Fructose Laurate Synthesized by Candida antarctica B Lipase-Mediated Transesterification.

    Science.gov (United States)

    Lee, Ki Ppeum; Kim, Hyung Kwoun

    2016-09-28

    Sugar esters are valuable compounds composed of various sugars and fatty acids that can be used as antibacterial agents and emulsifiers in toothpaste and canned foods. For example, fructose fatty acid esters suppress growth of Streptococcus mutans, a typical pathogenic bacterium causing dental caries. In this study, fructose laurate ester was chosen as a target material and was synthesized by a transesterification reaction using Candida antarctica lipase B. We performed a solvent screening experiment and found that a t-butanol/dimethyl sulfoxide mixture was the best solvent to dissolve fructose and methyl laurate. Fructose laurate was synthesized by transesterification of fructose (100 mM) with methyl laurate (30 mM) in t-butanol containing 20% dimethyl sulfoxide. The conversion yield was about 90%, which was calculated based on the quantity of methyl laurate using high-performance liquid chromatography. Fructose monolaurate (Mr 361) was detected in the reaction mixture by high-resolution mass spectrometry. The inhibitory effect of fructose laurate on growth of oral or food spoilage microorganisms, including S. mutans, Bacillus coagulans, and Geobacillus stearothermophilus, was evaluated.

  9. Silver nanoparticles well-dispersed in amine-functionalized, one-pot made vesicles as an effective antibacterial agent.

    Science.gov (United States)

    Deng, Yuanming; Li, Jiefeng; Yu, Junyan; Zhao, Jinlai; Tang, Jiaoning

    2016-03-01

    We report a simple route to prepare silver nanoparticle (Ag NP) loaded amine functionalized poly-oligomeric (ethylene glycol) methyl ether methacrylate block poly-glycidyl methacrylate (POEGMA-b-PGMA) vesicles as an effective antibacterial agent. Self-assemblies of POEGMA-b-PGMA were prepared from reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization mediated by a POEGMA macro-chain transfer agent (macro-CTA) in ethanol. Amine-functionalized self-assemblies were applied for Ag NP loading by using amine and hydroxyl groups as both the coordination agent and reductant under hydrothermal condition in high-pressure steam sterilization. 12.7 wt.% content of fine Ag NP well-dispersed in vesicles showed excellent antibacterial activities with the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) below 5.0 and 10.0 mg/L against Escherichia coli and 2.5 and 80 mg/L against Staphylococcus aureus respectively.

  10. Nucleoside Inhibitors of Tick-Borne Encephalitis Virus

    Science.gov (United States)

    Eyer, Luděk; Valdés, James J.; Gil, Victor A.; Nencka, Radim; Hřebabecký, Hubert; Šála, Michal; Salát, Jiří; Černý, Jiří; Palus, Martin; De Clercq, Erik

    2015-01-01

    Tick-borne encephalitis virus (TBEV) is a leading cause of human neuroinfections in Europe and Northeast Asia. There are no antiviral therapies for treating TBEV infection. A series of nucleoside analogues was tested for the ability to inhibit the replication of TBEV in porcine kidney cells and human neuroblastoma cells. The interactions of three nucleoside analogues with viral polymerase were simulated using advanced computational methods. The nucleoside analogues 7-deaza-2′-C-methyladenosine (7-deaza-2′-CMA), 2′-C-methyladenosine (2′-CMA), and 2′-C-methylcytidine (2′-CMC) inhibited TBEV replication. These compounds showed dose-dependent inhibition of TBEV-induced cytopathic effects, TBEV replication (50% effective concentrations [EC50]of 5.1 ± 0.4 μM for 7-deaza-2′-CMA, 7.1 ± 1.2 μM for 2′-CMA, and 14.2 ± 1.9 μM for 2′-CMC) and viral antigen production. Notably, 2′-CMC was relatively cytotoxic to porcine kidney cells (50% cytotoxic concentration [CC50] of ∼50 μM). The anti-TBEV effect of 2′-CMA in cell culture diminished gradually after day 3 posttreatment. 7-Deaza-2′-CMA showed no detectable cellular toxicity (CC50 > 50 μM), and the antiviral effect in culture was stable for >6 days posttreatment. Computational molecular analyses revealed that compared to the other two compounds, 7-deaza-2′-CMA formed a large cluster near the active site of the TBEV polymerase. High antiviral activity and low cytotoxicity suggest that 7-deaza-2′-CMA is a promising candidate for further investigation as a potential therapeutic agent in treating TBEV infection. PMID:26124166

  11. Copper and silver ion implantation of aluminium oxide-blasted titanium surfaces: proliferative response of osteoblasts and antibacterial effects.

    Science.gov (United States)

    Fiedler, Jörg; Kolitsch, Andreas; Kleffner, Bernhard; Henke, Dietmar; Stenger, Steffen; Brenner, Rolf E

    2011-09-01

    Implant infection still represents a major clinical problem in orthopedic surgery. We therefore tested the in vitro biocompatibility and antibacterial effects of copper (Cu)- and silver (Ag)-ion implantation. Discs of a commonly used titanium alloy (Ti6AlV4) with an aluminium oxide-blasted surface were treated by Cu- or Ag-ion implantation with different dosage regimen (ranging from 1e15-17 ions cm(-2) at energies of 2-20 keV). The samples were seeded with primary human osteoblasts and cell attachment and proliferation was analyzed by an MTT-assay. In comparison to the reference titanium alloy there was no difference in the number of attached viable cells after two days. After seven days the number of viable cells was increased for Cu with 1e17 ions cm(-2) at 2 and 5 keV, and for Ag with 1e16 ions cm(-2) at 5 keV while it was reduced for the highest amount of Ag deposition (1e17 ions cm(-2) at 20 keV). Antibacterial effects on S.aureus and E.coli were marginal for the studied dosages of Cu but clearly present for Ag with 1e16 ions cm(-2) at 2 and 5 keV and 1e17 ions cm(-2) at 20 keV. These results indicate that Ag-ion implantation may be a promising methodological approach for antibacterial functionalization of titanium implants.

  12. Antibacterial multifilament nylon sutures.

    Science.gov (United States)

    Singhal, J P; Singh, J; Ray, A R; Singh, H

    1991-01-01

    Multifilament nylon fibers were made antibacterial by dopping with iodine. Nylon fibers were immersed in acetone solution of iodine for 48 hours at room temperature for dopping of iodine. It was observed that iodine uptake by the nylon fibers increased with the increase in concentration of iodine in the solution. Antibacterial activity of these iodine dopped samples was evaluated by measuring the zone of inhibition. The bacterial species used for this study were Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Klebsiella pneumoniae. Iodine dopped fibers exhibited good antibacterial activity against these bacterial species. Release of iodine in distilled water is sustained for about 30 days. Antibacterial activity of the fibers decreases with the release of iodine in water. Ultra-violet and visible spectroscopic studies showed that tri-iodide ions were released from the dopped samples in the aqueous medium. These I3- ions might be responsible for the observed antibacterial activity. Fiber shrinks on iodine dopping leading to increase in the denier of the fiber. However effect of iodine dopping on the breaking load of fibers is not significant.

  13. Antibacterial Effects of the Essential Oils of Commonly Consumed Medicinal Herbs Using an In Vitro Model

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    Dejan Brkić

    2010-10-01

    Full Text Available The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determined. The antibacterial activity of these oils and their main components; i.e. camphor, carvacrol, 1,8-cineole, linalool, linalyl acetate, limonene, menthol, a-pinene, b-pinene, and thymol were assayed against the human pathogenic bacteria Bacillus subtilis, Enterobacter cloacae, Escherichia coli O157:H7, Micrococcus flavus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis, S. epidermidis, S. typhimurium, and Staphylococcus aureus. The highest and broadest activity was shown by O. vulgare oil. Carvacrol had the highest antibacterial activity among the tested components.

  14. COMPARATIVE EVALUATION OF THE ANTIBACTERIAL EFFECT OF CALCIUM HYDROXIDE PASTES USING FOUR DIFFERENT VEHIC LES

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    Ganesh

    2012-10-01

    Full Text Available ABSTRACT: AIM: The present study evaluated the antibacterial effec t of calcium hydroxide pastes using four different vehicles namely propylene glycol, glycerin, distilled water and camphorated phenol. MATERIAL AND METHOD: Calcium hydroxide pastes prepared with two commonly used vehicles namely distilled water and c amphorated phenol. The antibacterial activity of these pastes were tested against five a naerobic organism that can commonly occur in the infected root canal. The pastes were also prepare d using two chemicals such as propylene glycol and glycerin. RESULTS AND CONCLUSION: The result of this study show that calcium hydroxide paste made with propylene glycol gives enhan ced antibacterial action and sustains it for longer period of time. Propylene glycol being bi ological acceptable vehicle, it can be recommended for routine use as a vehicle over glyce rin

  15. Antibacterial Activity and Antibiotic-Enhancing Effects of Honeybee Venom against Methicillin-Resistant Staphylococcus aureus

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    Sang Mi Han

    2016-01-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA, along with other antibiotic resistant bacteria, has become a significant social and clinical problem. There is thus an urgent need to develop naturally bioactive compounds as alternatives to the few antibiotics that remain effective. Here we assessed the in vitro activities of bee venom (BV, alone or in combination with ampicillin, penicillin, gentamicin or vancomycin, on growth of MRSA strains. The antimicrobial activity of BV against MRSA strains was investigated using minimum inhibitory concentrations (MIC, minimum bactericidal concentrations (MBC and a time-kill assay. Expression of atl which encodes murein hydrolase, a peptidoglycan-degrading enzyme involved in cell separation, was measured by reverse transcription-polymerase chain reaction. The MICs of BV were 0.085 µg/mL and 0.11 µg/mL against MRSA CCARM 3366 and MRSA CCARM 3708, respectively. The MBC of BV against MRSA 3366 was 0.106 µg/mL and that against MRSA 3708 was 0.14 µg/mL. The bactericidal activity of BV corresponded to a decrease of at least 3 log CFU/g cells. The combination of BV with ampicillin or penicillin yielded an inhibitory concentration index ranging from 0.631 to 1.002, indicating a partial and indifferent synergistic effect. Compared to ampicillin or penicillin, both MRSA strains were more susceptible to the combination of BV with gentamicin or vancomycin. The expression of atl gene was increased in MRSA 3366 treated with BV. These results suggest that BV exhibited antibacterial activity and antibiotic-enhancing effects against MRSA strains. The atl gene was increased in MRSA exposed to BV, suggesting that cell division was interrupted. BV warrants further investigation as a natural antimicrobial agent and synergist of antibiotic activity.

  16. In Vitro Antibacterial Effects of Five Volatile Oil Extracts Against Intramacrophage Brucella Abortus 544

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    Ayman Al-Mariri

    2012-06-01

    Full Text Available Background: Brucella abortus is a gram-negative facultative intracellular bacterium that can cause a highly contagious disease in sheep, goats, cattle and one-humped camels. It is responsible for one of the most important zoonosis in human. The aim of this study was to evaluate the role of Mentha piperita, Origanum majorana, Citrus lemon, Cinnamomum verum and Myristica fragrans essential volatile oil extracts on human macrophages infected by B. abortus 544. Methods: Essential volatile oil extracts from M. piperita, O. majorana, C. lemon, C. verum and M. fragrans were extracted. Human macrophages were cultured at a density of 2×105 cells per well in sterile 96-well microtiter plates, and infected with B. abortus 544 at a ratio of 1:100 bacteria/cell. Then essential volatile oil extracts were added at a concentration of 1%. At specified times; cells were washed, lysed with 0.1% Triton, and plated on 2YT agar to determine the number of intracellular bacteria. Results: Cinnamomum verum volatile oil at a concentration of 1% had the highest antibacterial activity against B. abortus 544 inside human macrophages. Its inhibitory effect observed from 24 h and continued till 144 h after the infection. Moreover, C. verum (0.1% in combination with 1% concentration of M. piperita, O. majorana, C. lemon or M. fragrans volatile oil extracts produced a synergistic inhibitory effect against B. abortus 544. Conclusion: The results indicate that, among the five selected oil extracts, C. verum volatile oil applied either separately or in combination with other oil extracts had the most effective antimicrobial activity against Brucella.

  17. Ozone correlates with antibacterial effects from indirect air dielectric barrier discharge treatment of water

    Science.gov (United States)

    Pavlovich, Matthew J.; Chang, Hung-Wen; Sakiyama, Yukinori; Clark, Douglas S.; Graves, David B.

    2013-04-01

    Ambient-condition air plasma produced by indirect dielectric barrier discharges can rapidly disinfect aqueous solutions contaminated with bacteria and other microorganisms. In this study, we measured key chemical species in plasma-treated aqueous solutions and the associated antimicrobial effect for varying discharge power densities, exposure times, and buffer components in the aqueous medium. The aqueous chemistry corresponded to air plasma chemistry, and we observed a transition in composition from ozone mode to nitrogen oxides mode as the discharge power density increased. The inactivation of E. coli correlates well with the aqueous-phase ozone concentration, suggesting that ozone is the dominant species for bacterial inactivation under these conditions. Published values of ozone-water antibacterial inactivation kinetics as a function of the product of ozone concentration and contact time are consistent with our results. In contrast to earlier studies of plasma-treated water disinfection, ozone-dependent bacterial inactivation does not require acidification of the aqueous medium and the bacterial inactivation rates are far higher. Furthermore, we show that the antimicrobial effect depends strongly on gas-liquid mixing following plasma treatment, apparently because of the low solubility of ozone and the slow rate of mass transfer from the gas phase to the liquid. Without thorough mixing of the ozone-containing gas and bacteria-laden water, the antimicrobial effect will not be observed. However, it should be recognized that the complexity of atmospheric pressure plasma devices, and their sensitivity to subtle differences in design and operation, can lead to different results with different mechanisms.

  18. In situ enzymatic removal of orthophosphate by the nucleoside phosphorylase catalyzed phosphorolysis of nicotinamide riboside.

    Science.gov (United States)

    Shriver, J W; Sykes, B D

    1982-09-01

    An enzymatic orthophosphate removal system is described which can be effectively used to continuously remove orthophosphate from biochemical samples. The phosphorolysis of nicotinamide riboside is catalyzed by calf spleen nucleoside phosphorylase to give ribose-1-PO4 and nicotinamide along with a proton. At pH 8 the production of ribose-1-PO4 from orthophosphate is essentially quantitative. This reaction can be monitored optically or by 31P nuclear magnetic resonance (NMR). Equations are given for determining the time required to remove a given amount of phosphate from a typical NMR sample with a known amount of nucleoside phosphorylase. The effects of a competing orthophosphate-producing reaction are considered.

  19. Effect of extrusion processing on the microstructure, mechanical properties, biocorrosion properties and antibacterial properties of Ti-Cu sintered alloys.

    Science.gov (United States)

    Zhang, Erlin; Li, Shengyi; Ren, Jing; Zhang, Lan; Han, Yong

    2016-12-01

    Ti-Cu sintered alloys, Ti-Cu(S) alloy, have exhibited good anticorrosion resistance and strong antibacterial properties, but low ductility in previous study. In this paper, Ti-Cu(S) alloys were subjected to extrusion processing in order to improve the comprehensive property. The phase constitute, microstructure, mechanical property, biocorrosion property and antibacterial activity of the extruded alloys, Ti-Cu(E), were investigated in comparison with Ti-Cu(S) by X-ray diffraction (XRD), optical microscopy (OM), scanning electronic microscopy (SEM) with energy disperse spectroscopy (EDS), mechanical testing, electrochemical testing and plate-count method in order to reveal the effect of the extrusion process. XRD, OM and SEM results showed that the extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly. Ti-Cu(E) alloys exhibited higher hardness and compressive yield strength than Ti-Cu(S) alloys due to the fine grain and Ti2Cu particles. With the consideration of the total compressive strain, it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S) alloys. Electrochemical results have indicated that the extrusion process improved the corrosion resistance of Ti-Cu(S) alloys. Plate-count method displayed that both Ti-Cu(S) and Ti-Cu(E) exhibited strong antibacterial activity (>99%) against S. aureus. All these results demonstrated that hot forming processing, such as the extrusion in this study, refined the microstructure and densified the alloy, in turn improved the ductility and strength as well as anticorrosion properties without reduction in antibacterial properties.

  20. The Effect of Ag Content of the Chitosan-Silver Nanoparticle Composite Material on the Structure and Antibacterial Activity

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    Solmaz Akmaz

    2013-01-01

    Full Text Available The aim of this study is to investigate the antibacterial properties and characterization of chitosan-silver nanoparticle composite materials. Chitosan-silver nanoparticle composite material was synthesized by adding AgNO3 and NaOH solutions to chitosan solution at 95°C. Different concentrations (0,02 M, 0,04 M, and 0,06 M of AgNO3 were used for synthesis. Chitosan-silver nanoparticle composite materials were characterized by Transmission electron microscopy (TEM, X-ray diffraction (XRD, ultraviolet (UV spectrophotometer, and Fourier transform infrared (FTIR spectrometer techniques. Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Streptococcus pneumoniae were used to test the bactericidal efficiency of synthesized chitosan-Ag nanoparticle composite materials. The biological activity was determined by the minimum bacterial concentration (MBC of the materials. Antibacterial effect of chitosan-silver nanoparticle materials was increased by increasing Ag amount of the composite materials. The presence of small amount of metal nanoparticles in the composite was enough to significantly enhance antibacterial activity as compared with pure chitosan.

  1. [Antibacterial effect of food additives and detergents against histamine-producing bacteria on food contact material surfaces].

    Science.gov (United States)

    Kamii, Eri; Terada, Gaku; Akiyama, Junki; Isshiki, Kenji

    2011-01-01

    We investigated the antibacterial activity of food additives and detergents against histamine-producing bacteria on food contact material surfaces. Based on minimum inhibitory concentration (MIC) testing with Morganella morganii NBRC3848, Raoultella planticola NBRC3317 and Enterobacter aerogenes NCTC10006, we screened nine food additives and four detergents with relatively high inhibitory potency. We prepared food contact material surfaces contaminated with histamine-producing bacteria, and dipped them into fourteen agents (100 µg/mL). Sodium hypochlorite, benzalkonium chloride, benzethonium chloride, n-hexadecyltrimethylammonium chloride and 1-n-hexadecylpyridinium chloride showed antibacterial activity against histamine-producing bacteria. We prepared low concentrations of the five agents (10 and 50 µg/mL) and tested them in the same way. Sodium hypochlorite showed high antibacterial activity at 10 µg/mL, and the other four showed activity at 50 µg/mL. So, washing the material surface with these reagents might be effective to prevent histamine food poisoning owing to bacterial contamination of food contact surfaces.

  2. Carbon Nanomaterials as Antibacterial Colloids

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    Michael Maas

    2016-07-01

    Full Text Available Carbon nanomaterials like graphene, carbon nanotubes, fullerenes and the various forms of diamond have attracted great attention for their vast potential regarding applications in electrical engineering and as biomaterials. The study of the antibacterial properties of carbon nanomaterials provides fundamental information on the possible toxicity and environmental impact of these materials. Furthermore, as a result of the increasing prevalence of resistant bacteria strains, the development of novel antibacterial materials is of great importance. This article reviews current research efforts on characterizing the antibacterial activity of carbon nanomaterials from the perspective of colloid and interface science. Building on these fundamental findings, recent functionalization strategies for enhancing the antibacterial effect of carbon nanomaterials are described. The review concludes with a comprehensive outlook that summarizes the most important discoveries and trends regarding antibacterial carbon nanomaterials.

  3. Rice husk based porous carbon loaded with silver nanoparticles by a simple and cost-effective approach and their antibacterial activity.

    Science.gov (United States)

    Cui, Jianghu; Yang, Yunhua; Hu, Yonghui; Li, Fangbai

    2015-10-01

    In this paper, we chose rice husk as raw material and synthesized successfully porous carbon loaded with silver nanoparticles (RH-Ag) composites by simple and cost-effective method. The as-prepared RH-Ag composites have a BET-specific surface area of 1996 m(2) g(-1) and result in strong capacity of bacteria adsorption. The result of antibacterial study indicated that the RH-Ag system displayed antibacterial activity that was two times better than pure Ag NPs. Our study demonstrates that the antibacterial activity of RH-Ag composites may be attributed to their strong adsorption ability with bacteria and result in the disorganization of the bacterial membrane ultrastructure. In addition, RH-Ag system was found to be durative slow-releasing of silver ions and biocompatible for human skin keratinocytes cells. In terms of these advantages, the RH-Ag composites have potential application in antibacterial infections and therapy.

  4. MAIN FACTORS IN PREPARATION OF ANTIBACTERIAL PARTICLES/PVC COMPOSITE

    Institute of Scientific and Technical Information of China (English)

    Xuehua Chen; Chunzhong Li; Ling Zhang; Shoufang Xu; Qiuling Zhou; Yihua Zhu; Xianzhang Qu

    2004-01-01

    Zirconium phosphate containing silver was chosen as antibacterial particles in preparing antibacterial particles/PVC composite. The effect of surface property of the antibacterial particles and of their filler content on the properties of antibacterial particles/PVC composite was studied. The effect of the interfacial compatibility on mechanical properties of the composite was also discussed. Experimental results showed that the antibacterial PVC composite had good antibacterial property, reaching almost 100% bacteriostatic level at an antibacterial powder filler content of 1.5 phr.

  5. Preparation and Characterization of Nylon 6/Silver Nanocomposite Fibers for Permanent Antibacterial Effect

    Directory of Open Access Journals (Sweden)

    Laleh Maleknia

    2015-03-01

    Full Text Available The nylon 6/silver nano composite fibers were prepared for the attainment of permanent antibacterial activity to common synthetic textile. The fibers prepared by melt spinning and nylon 6/ Silver nanocomposite were prepared by a modular twin screw extruder.. The antibacterial activities of nano silver in fibers were calculated by percent reduction of two kinds of bacteria staphylococcus aurous and klebsiela peneumoniae. Scanning electron microscopy (SEM was carried out to observe particle distribution on the nanocomposite fibers. All the nanocomposite fibers were characterized by instron machine.

  6. Antibacterial, antibiofilm and cytotoxic effects of Nigella sativa essential oil coated gold nanoparticles.

    Science.gov (United States)

    Manju, Sivalingam; Malaikozhundan, Balasubramanian; Vijayakumar, Sekar; Shanthi, Sathappan; Jaishabanu, Ameeramja; Ekambaram, Perumal; Vaseeharan, Baskaralingam

    2016-02-01

    This study reports the biological synthesis of gold nanoparticles using essential oil of Nigella sativa (NsEO-AuNPs). The synthesized NsEO-AuNPs were characterized by UV-visible spectra, X-ray diffraction (XRD), FTIR and Transmission electron microscopy (TEM). UV-vis spectra of NsEO-AuNPs showed strong absorption peak at 540 nm. The X-ray diffraction analysis revealed crystalline nature of nanoparticle with distinctive facets (111, 200, 220 and 311 planes) of NsEO-AuNPs. The FTIR spectra recorded peaks at 3388, 2842, 1685, 1607, 1391 and 1018 cm(-1). TEM studies showed the spherical shape of nanoparticles and the particle size ranges between 15.6 and 28.4 nm. The antibacterial activity of NsEO-AuNPs was greater against Gram positive Staphylococcus aureus MTCC 9542 (16 mm) than Gram negative Vibrio harveyi MTCC 7771 (5 mm) at the concentration of 10 μg ml(-1). NsEO-AuNPs effectively inhibited the biofilm formation of S. aureus and V. harveyi by decreasing the hydrophobicity index (78% and 46% respectively). The in-vitro anti-lung cancer activity confirmed by MTT assay on the cell line of A549 carcinoma cells showed IC50 values of bulk Au at 87.2 μg ml(-1), N. sativa essential oil at 64.15 μg ml(-1) and NsEO-AuNPs at 28.37 μg ml(-1). The IC50 value showed that NsEO-AuNPs was highly effective in inhibiting the A549 lung cancer cells compared to bulk Au and N. sativa essential oil.

  7. Assessment of antibacterial effect of garlic in patients infected with Helicobacter pylori using urease breath test

    Science.gov (United States)

    Zardast, Mahmoud; Namakin, Kokab; Esmaelian Kaho, Jamil; Hashemi, Sarira Sadat

    2016-01-01

    Objective: Helicobacter pylori (H. pylori) is the most common pathogenic bacteria in the stomach. The aim of the current study was to explore the effect of oral garlic administration on bacterial urease activity inside the stomach and its contribution to the treatment of H. pylori infection. Materials and Methods: In this clinical trial, 15 patients were studied quantitatively with Urease Breath Test (UBT). The patients with gastrointestinal symptoms and a positive serum H. pylori IgG were enrolled. UBT was performed for each patient in three sessions as follows: at the beginning of the study, an initial UBT was performed based on which, the positive cases entered the study and the negative ones were excluded. Second UBT was done three days later in patients who were not receiving any treatment and were considered as the control, whereas the third UBT was performed three days after prescribing two medium-sized cloves of garlic (3 g) with their meal, twice a day (at noon and in the evening). The collected data were analyzed using ANOVA and Bonferroni tests and the significance level was set at p<0.05. Results: the mean UBT significantly differed before and after treatment with garlic cloves, being significantly lower after garlic consumption. No meaningful difference was observed in the mean UBT without garlic consumption between the first and second steps. Conclusion: Raw garlic has anti-bacterial effects against H. pylori residing in the stomach and may be prescribed along with routine drugs for the treatment of gastric H. pylori infection. PMID:27761418

  8. Radiographic, antibacterial and bond-strength effects of radiopaque caries tagging

    Science.gov (United States)

    Umwali, Aurore; Askar, Haitham; Paris, Sebastian; Schwendicke, Falk

    2016-01-01

    Selectively excavated carious lesions remain radiographically detectable. Radiopaque tagging could resolve the resulting diagnostic uncertainty. We aimed to evaluate if tagging depends on lesions depths, is antibacterial, or affects dentin bond-strengths. Artificial lesions (depth-range: 152–682 μm, n = 34/group) were induced in human dentin samples, evaluated using wavelength-independent microradiography, treated with one of two tagging materials (70% SnCl2, 30% SnF2) and re-evaluated. To evaluate antimicrobial effects, 40 dentin samples were submitted to a Lactobacillus rhamnosus invasion-model. Infected samples were treated with placebo, 0.2% chlorhexidine, SnCl2, SnF2 (n = 10/group). Dentin was sampled and colony-forming units/mg determined. Micro-tensile bond-strengths of adhesive restorations (OptiBond FL, Filtek Z250) to tagged or untagged, sound and carious dentin were assessed (n = 12/group). Tagged surfaces were evaluated microscopically and via energy-dispersive X-ray-spectroscopy (EDS). Tagging effects of both materials decreased with increasing lesion depths (p < 0.001). Un-/chlorhexidine-treated dentin contained significantly more viable bacteria (median 7.3/3.7 × 105 CFU/mg) than tagged dentin (no CFU detectable, p < 0.001). Tagging decreased bond strengths (p < 0.001) on sound (−22%/−33% for SnCl2/SnF2) and carious dentin (−50%/−54%). This might be due to widespread tin chloride or fluoride precipitation, as detected via microscopy and EDS. While radiopaque tagging seems beneficial, an optimized application protocol needs to be developed prior clinical use. PMID:27251174

  9. Assessment of antibacterial effect of cinnamon on growth of porphyromons gingivalis from chronic periodontitis patients with deep pockets (in vitro

    Directory of Open Access Journals (Sweden)

    Babak Amoian

    2014-04-01

    Full Text Available   Background and Aims : Antibiotics are commonly used for controlling the growth of porphyromons gingivalis (P.g which is one of the most important etiologic factors in the periodontal diseases. Different side effects of synthetics and chemical drugs such as increasing the drug resistancy in the human pathogens have led to study on the herbal antibacterial effect. The aim of this study was to evaluate the antibacterial effect of cinnamon on the growth of porphyromons gingivalis in chronic periodontitis patients with deep pockets.   Materials and Methods: In this experimental study, samples were provided from patients having pockets. After culturing the microorganism and diagnosis of P.g by gram staining and biochemical tests, cinnamon in different concentrations (10, 50, 100, 250, 500, 750 and 1500 mg/ml with oil solvent were prepared and placed by disks in the cultures medium. Positive controls were amoxicillin, metronidazole, ciprofloxacin, amikacin and gentamycin . Oil was negative control. Then the plates were incubated for 24 hours in 37 0 C and then non-growth halos by disk diffusion method, MIC (Minimum Inhibitory Concentration and MBC (Minimum Bactericidal Concentration were determined. Data were analyzed using One-way ANOVA test.   Results: The results showed that the cinnamon at the concentration of MIC=750 mg/ml had the inhibitory effects of bacteria and at the concentration of MIC=1500 mg/ml had killing effect. However, this antibacterial effect compared with commonly used antibiotics (amoxicillin, metronidazole, was much weaker (P<0.001.   Conclusion: Cinnamon showed an antimicrobial effect on porphyromonas gingivalis in chronic periodontitis patients with deep pockets.

  10. Evaluation of anti-bacterial effects of some novel thiazole and imidazole derivatives against some pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Behzad Ghasemi

    2015-12-01

    Full Text Available Background and Objectives: Bacterial resistance to antibiotics has motivated the researchers to evaluate the novel anti-bac- terial compounds such as some thiazole and imidazole derivatives. Thereby, in this work, we investigated the anti-bacterial effects of one new thiazole and two new imidazole derivatives on Bacillus cereus, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, Proteus mirabilis and Shigella dysenteriae.Materials and Methods: The thiazole and imidazole derivatives were dissolved in DMSO. The disk diffusion method was utilized to measure the growth inhibition zone diameter values, and the broth micro-dilution method was applied to deter- mine the minimum inhibitory concentration (MIC values.Results: The synthesized imidazole derivatives lacked any inhibitory effect against the tested bacteria. On the other hand, although the synthesized thiazole derivative showed no inhibitory effect against Bacillus cereus, Salmonella typhimurium, and Escherichia coli, it inhibited the growth of Proteus mirabilis, Shigella dysenteriae, and Listeria monocytogenes with the MIC values of 1000, 125, and 1000 µg/ml, respectively, and the growth inhibition zone diameter values of 9.3 ± 0.1, 15.6 ± 0.2, and 8.1 ± 0.0 mm, respectively.Conclusion: The anti-bacterial effect of the synthesized thiazole derivative on Shigella dysenteriae, Proteus mirabilis and Listeria monocytogenes was proven. However, its inhibition effect against Shigella dysenteriae was more than that against the others. Many in-vitro and in-vivo experiments are required to evaluate the effects of this compound on the bacteria and the human body. Keywords: Anti-bacterial effects, Thiazole, Imidazole

  11. Anti-bacterial Studies of Silver Nanoparticles

    CERN Document Server

    Theivasanthi, T

    2011-01-01

    We discuss about the antibacterial activities of Silver nanoparticles and compare them on both Gram negative and Gram positive bacteria in this investigation. The activities of Silver nanoparticles synthesized by electrolysis method are more in Gram (-) than Gram (+) bacteria. First time, we increase its antibacterial activities by using electrical power while on electrolysis synthesis and it is confirmed from its more antibacterial activities (For Escherichia coli bacteria). We investigate the changes of inner unit cell Lattice constant of Silver nanoparticles prepared in two different methods and its effects on antibacterial activities. We note that slight change of the lattice constant results in the enhancement of its antibacterial activities.

  12. Effects of antibacterial agents on in vitro ovine ruminal biotransformation of the hepatotoxic pyrrolizidine alkaloid jacobine.

    OpenAIRE

    1992-01-01

    Ingestion of pyrrolizidine alkaloids, naturally occurring plant toxins, causes illness and death in a number of animal species. Senecio jacobaea pyrrolizidine alkaloids cause significant economic losses due to livestock poisoning, particularly in the Pacific Northwest. Some sheep are resistant to pyrrolizidine alkaloid poisoning, because ovine ruminal biotransformation detoxifies free pyrrolizidine alkaloids in digesta. Antibacterial agents modify ruminal fermentation. Pretreatment with antib...

  13. Assessment of nanopolyamidoamine-G7 dendrimer antibacterial effect in aqueous solution

    Directory of Open Access Journals (Sweden)

    Mitra Gholami

    2016-06-01

    Conclusion: The NPAMAM-G7 dendrimer with end amine groups exhibited a positive impact on the removal of standard strains, gram-positive and gram-negative bacteria. Therefore, it is possible to use these nanodendrimers as antibacterial in the future.

  14. Apoptosis induced by nucleosides in the human hepatoma HepG2

    Institute of Scientific and Technical Information of China (English)

    Suh-Ching Yang; Che-Lin Chiu; Chi-Chang Huang; Jiun-Rong Chen

    2005-01-01

    AIM: To investigate the apoptotic effects of nucleosides on the human hepatoma HepG2.METHODS: The nucleosides included inosine (I), cytidine(C), uridine (U), thymidine (T), adenosine (A), and guanosine (G). Cells were incubated by the mediums with or without nucleosides at 37 ℃ in a 50 mL/L CO2 humidified atmosphere.RESULTS: It was found that the cell viabilities were significantly decreased, when cells were treated with 30 mmol/L I, 30 mmol/L C, 30 mmol/L U, 30 mmol/L T,0.5 mmol/L A, and 0.5 mmol/L G after 12 h incubation (P<0.05). About the apoptotic phenomenon, the cell percentages of sub-G1 cells were significantly increased in the mediums containing nucleosides such as C, U, T,A, and G (P<0.05). Furthermore, the caspase-3 activity was increased, when the cells were incubated with T(P<0.05). The protein expressions of p53 and p21 showed no difference in each group. To investigate the mechanism of apoptosis induced by nucleosides, it was found that the contents of soluble Fas ligand contents were increased in HepG2 cells following I, U, T, and A treatment (P<0.05).But, TNF-α and cytochrome c were undetectable.CONCLUSION: Thymidine may induce the apoptosis in HepG2, but the effective dosages and reactive time must be investigated in the future study. However, the apoptosis-inducing abilities of other nucleosides were still unclear in this study.

  15. [Bactericid and fungicid polymers in dentistry. Polyethyleneimine, a new effective antibacterial and antifungal cationic polymer and its dental application].

    Science.gov (United States)

    Géczi, Zoltán; Kispélyi, Barbara; Pál, Károly; Hermann, Péter

    2016-06-01

    In the past years antibacterial and antifungal polymers had become the focus of medical research. Polyethylenimine (PEI) and poliamidoamin had been proven the most effective polymers. The data shown in this short review discuss the chemical structure, pharmacological effects and medical use of PEI. Report in the international literature only gives examples of experimental dental appliance of PEI in sealers and filling materials. Because of the growing interest in the subject of PEI we find it important to inform the domestic dental society of cationic polymers.

  16. Putative histidine kinase inhibitors with antibacterial effect against multi-drug resistant clinical isolates identified by in vitro and in silico screens

    Science.gov (United States)

    Velikova, Nadya; Fulle, Simone; Manso, Ana Sousa; Mechkarska, Milena; Finn, Paul; Conlon, J. Michael; Oggioni, Marco Rinaldo; Wells, Jerry M.; Marina, Alberto

    2016-05-01

    Novel antibacterials are urgently needed to address the growing problem of bacterial resistance to conventional antibiotics. Two-component systems (TCS) are widely used by bacteria to regulate gene expression in response to various environmental stimuli and physiological stress and have been previously proposed as promising antibacterial targets. TCS consist of a sensor histidine kinase (HK) and an effector response regulator. The HK component contains a highly conserved ATP-binding site that is considered to be a promising target for broad-spectrum antibacterial drugs. Here, we describe the identification of putative HK autophosphorylation inhibitors following two independent experimental approaches: in vitro fragment-based screen via differential scanning fluorimetry and in silico structure-based screening, each followed up by the exploration of analogue compounds as identified by ligand-based similarity searches. Nine of the tested compounds showed antibacterial effect against multi-drug resistant clinical isolates of bacterial pathogens and include three novel scaffolds, which have not been explored so far in other antibacterial compounds. Overall, putative HK autophosphorylation inhibitors were found that together provide a promising starting point for further optimization as antibacterials.

  17. Effects of Different Systemic Insecticides in Carotenoid Content, Antibacterial Activity and Morphological Characteristics of Tomato (Solanum lycopersicum var Diamante

    Directory of Open Access Journals (Sweden)

    LEXTER R. NATIVIDAD

    2014-02-01

    Full Text Available This study aimed to determine the effects of different systemic insecticides in tomato (Lycopersicon esculentum var. Diamante. The study also assessed different systemic insecticides used in other plants in their effectiveness and suitability to tomato by evaluating the carotenoid content and antibacterial activity of each insecticide. Morphological characteristics such as the weight, the number and the circumference of tomato fruits and the height of the plant were also observed. Moreover, the cost effectiveness was computed. Treatments were designated as follows: Treatment 1- plants sprayed with active ingredient (a.i. cartap hydrochloride; Treatment 2 - plants sprayed with a.i. indoxacarb; Treatment 3- plants sprayed with a.i. chlorantraniliprole and thiamethoxam; Treatment 4 - plants sprayed with a.i. dinotefuran (positive control; and Treatment 5 - no insecticide applied. The experimental design used was Randomized Complete Block Design (RCBD with three replications. The first three systemic insecticides with such active ingredient were not yet registered for tomato plant. Statistical analyses show that there were no significant differences among the weight, the number and the circumference of tomato fruits and the height of the plant for each treatment. Results showed that treatments 1, 2, 3, 4 and 5 extracts have 49.74, 44.16, 48.19, 52.57 and 50.60 μg/g of total carotenoids (TC, respectively. Statistical analysis shows that there no significant differences in the TC content of each treatment. The antibacterial activity of each plant sample showed no significant differences among treatments. Thin layer chromatographic analysis revealed that there were equal numbers of spots for all the plant samples.The study concluded that systemic insecticide with a.i. cartap hydrochloride be introduced to the farmers as insecticide for tomato plant since it shows comparable effect with the registered insecticide (T4 based on the morphological

  18. Antibacterial potential of contemporary dental luting cements.

    Science.gov (United States)

    Daugela, Povilas; Oziunas, Rimantas; Zekonis, Gediminas

    2008-01-01

    The aims of this investigation were to evaluate the antibacterial activities of different types of dental luting cements and to compare antibacterial action during and after setting. Agar diffusion testing was used to evaluate the antibacterial properties of seven types of dental luting cements (glass ionomer cements (GICs), resin modified GICs, resin composite, zinc oxide eugenol, zinc oxide non-eugenol, zinc phosphate, zinc polycarboxylate cements) on Streptococcus mutans bacteria. Instantly mixed zinc phosphate cements showed the strongest antibacterial activity in contrast to the non-eugenol, eugenol and resin cements that did not show any antibacterial effects. Non-hardened glass ionomer, resin modified and zinc polycarboxylate cements exhibited moderate antibacterial action. Hardened cements showed weaker antibacterial activities, than those ones applied right after mixing.

  19. Evaluation of chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effects of Aloysia citrodora extract on colon cancer cell line

    Directory of Open Access Journals (Sweden)

    Amir Mirzaie

    2016-06-01

    Full Text Available Background: Aloysia citrodora belongs to the Verbenaceae family of plants, a well-known herbal medicine in Iran. The aim of the present study was to investigate the chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effect of A. citrodora extract against human colon cancer (HT29 cells by using real-time polymerase chain reaction and flow-cytometry methods. Methods: This experimental study was carried out in Islamic Azad University, East Tehran Branch, from March to September of 2014. At first, the A. citrodora chemical constituents were analyzed by gas chromatography-mass spectrometry (GC-MS technique. In addition, antioxidant assay, antibacterial and anti-cancer effect was performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH, disk diffusion and 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT methods, respectively. The half maximal inhibitory concentration (IC50 value was calculated. We extracted total RNA molecules by using RNX solution, after which cDNA was synthesized. Finally, the pro-apoptotic (Bax and anti-apoptotic (Bcl2 gene expression was performed by real-time polymerase chain reaction and apoptotic effects were analyzed using Flow-cytometry method. Results: GC-MS analysis of Aloysia citrodora extract was shown 37 major components and the most frequent component was belonged to Spathulenol (17.57% and Caryophyllene oxide (15.15% The antioxidant activity of the extract was IC50= 0.6±0.03 mg/ml. The maximum and minimum antibacterial effects of extract were belonged to gram-negative and gram-positive bacteria, respectively. Cytotoxic results revealed that the A.citrodora extract have IC50= 20.1±0.78 mg/ml against colon cancer (HT29 cell line and real-time polymerase chain reaction results showed the expression level of Bax and Bcl2 was increased and decreased respectively in colon cancer cell line (3.470±0.72 (P< 0.05, 0.43±0.35 (P< 0.05. In addition, the flow-cytometry results indicated the 38

  20. Discriminatory antibacterial effects of calix[n]arene capped silver nanoparticles with regard to gram positive and gram negative bacteria.

    Science.gov (United States)

    Boudebbouze, Samira; Coleman, Anthony W; Tauran, Yannick; Mkaouar, Hela; Perret, Florent; Garnier, Alexandrine; Brioude, Arnaud; Kim, Beomjoon; Maguin, Emmanuelle; Rhimi, Moez

    2013-08-18

    Silver nanoparticles capped with nine different sulphonated calix[n]arenes were tested for their anti-bacterial effects against B. subtilis and E. coli at an apparent concentration of 100 nM in calix[n]arene. The results show the para-sulphonato-calix[n]arenes are active against Gram positive bacteria and the derivatives having sulphonate groups at both para and alkyl terminal positions are active against Gram negative bacteria. The calix[6]arene derivative with only O-alkyl sulphonate groups shows bactericidal activity.

  1. Distribution of Nucleosides in Populations of Cordyceps cicadae

    OpenAIRE

    Wen-Bo Zeng; Hong Yu; Feng Ge; Jun-Yuan Yang; Zi-Hong Chen; Yuan-Bing Wang; Yong-Dong Dai; Alison Adams

    2014-01-01

    A rapid HPLC method had been developed and used for the simultaneous determination of 10 nucleosides (uracil, uridine, 2'-deoxyuridine, inosine, guanosine, thymidine, adenine, adenosine, 2'-deoxyadenosine and cordycepin) in 10 populations of Cordyceps cicadae, in order to compare four populations of Ophicordyceps sinensis and one population of Cordyceps militaris. Statistical analysis system (SAS) 8.1 was used to analyze the nucleoside data. The pattern of nucleoside distribution was analyzed...

  2. Nucleosides and ODN electrochemical detection onto boron doped diamond electrodes.

    Science.gov (United States)

    Fortin, Elodie; Chane-Tune, Jérôme; Mailley, Pascal; Szunerits, Sabine; Marcus, Bernadette; Petit, Jean-Pierre; Mermoux, Michel; Vieil, Eric

    2004-06-01

    Boron doped diamond (BDD) is a promising material for electroanalytical chemistry due mainly to its chemical stability, its high electrical conductivity and to the large amplitude of its electroactive window in aqueous media. The latter feature allowed us to study the direct oxidation of the two electroactive nucleosides, guanosine and adenosine. The BDD electrode was first activated by applying high oxidizing potentials, allowing to increase anodically its working potential window through the oxidation of CH surface groups into hydroxyl and carbonyl terminations. Guanosine (1.2 V vs. Ag/AgCl) and adenosine (1.5 V vs. Ag/AgCl) could then be detected electrochemically with an acceptable signal to noise ratio. The electrochemical signature of each oxidizable base was assessed using differential pulse voltammetry (DPV), in solutions containing one or both nucleosides. These experiments pointed out the existence of adsorption phenomena of the oxidized products onto the diamond surface. Scanning electrochemical microscopy (SECM) was used to investigate these adsorption effects at the microscopic scale. The usefulness of BDD electrodes for the direct electrochemical detection of synthetic oligonucleotides is also evidenced.

  3. Antibacterial effects of medicinal plant extracts against Lactococcus garvieae, the etiological agent of rainbow trout lactococcosis

    Directory of Open Access Journals (Sweden)

    Mohammad Saeid Fereidouni

    2013-05-01

    Full Text Available Eight medicinal plants were assessed for antimicrobial activity against Lactococcus garvieae isolate obtained from diseased Oncorhynchus mykiss collected from rainbow trout fish farms in Iran. Lactococcus garvieae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems. The antibacterial activity of the medicinal plants against L. garvieae was evaluated using disc diffusion, well diffusion and minimum inhibitory concentration. Results showed that the extracts and essential oils had a relatively high antibacterial activity against L. garvieae. Of the plants studied, the most active extracts were those from the methanol extract of Peganum harmala, the essential oil of Satureja bachtiarica, the ethanol extract of Juglans regia and Trachyspermum copticum with minimum inhibitory concentration (MIC of 105, 126, 510 and 453 μg/ml, respectively. Conversly, some of the extracts such as Quercus branti Lindley and Glycyrrhiza glabra L. had lower activity against L. garvieae with MIC values of 978 and 920 μg/ml respectively. Plant extracts as natural and environment- friendly compounds can be an important source of antibacterial agents against L. garvieae. They may be used for disinfection of instruments and rainbow trout raceways or treatment of the fish.

  4. Stable and efficient loading of silver nanoparticles in spherical polyelectrolyte brushes and the antibacterial effects.

    Science.gov (United States)

    Liu, Xiaochi; Xu, Yisheng; Wang, Xiaohan; Shao, Mingfei; Xu, Jun; Wang, Jie; Li, Li; Zhang, Rui; Guo, Xuhong

    2015-03-01

    A more efficient and convenient strategy was demonstrated to immobilize silver nanoparticles (NPs) with a crystalline structure into the spherical polyelectrolyte brushes (SPB) as an antibacterial material. The SPB used for surface coating (Ag immobilized PVK-PAA SPB) consists of a poly(N-vinylcarbazole) (PVK) core and poly(acrylic acid) (PAA) chain layers which are anchored onto the surface of PVK core at one end. Well-dispersed silver nanoparticles (diameter∼3.5 nm) then formed and were electrostatically confined in the brush layer. Ag content is controlled by a repeated loading process. Thin film coatings were then constructed by layer-by-layer depositions of positive charged poly(diallyldimethylammonium chloride) (PDDA) and SPB. The multilayer composites display excellent stability as well as antibacterial performance but not for simple PVK-PAA coated surface. The results show that almost complete bacteria growth including both dispersed bacterial cells and biofilms was inhibited over a period of 24 h. This approach opens a novel strategy for stable and efficient immobilization of Ag NPs in fabrication of antibacterial materials.

  5. Antibacterial effects of silver-doped hydroxyapatite thin films sputter deposited on titanium

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo, Nathan A. [Dept. of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523-1374 (United States); School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523-1376 (United States); Oldinski, Rachael A. [College of Engineering and Mathematical Science, University of Vermont, Burlington, VT 05405 (United States); Dept. of Bioengineering, University of Washington, Seattle, WA 98195-5061 (United States); Ma, Hongyan; Bryers, James D. [Dept. of Bioengineering, University of Washington, Seattle, WA 98195-5061 (United States); Williams, John D. [Dept. of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523-1374 (United States); Popat, Ketul C., E-mail: Ketul.Popat@colostate.edu [Dept. of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523-1374 (United States); School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523-1376 (United States)

    2012-12-01

    Since many orthopedic implants fail as a result of loosening, wear, and inflammation caused by repeated loading on the joints, coatings such as hydroxyapatite (HAp) on titanium with a unique topography have been shown to improve the interface between the implant and the natural tissue. Another serious problem with long-term or ideally permanent implants is infection. It is important to prevent initial bacterial colonization as existing colonies have the potential to become encased in an extracellular matrix polymer (biofilm) that is resistant to antibacterial agents. In this study, plasma-based ion implantation was used to examine the effects of pre-etching on plain titanium. Topographical changes to the titanium samples were examined and compared via scanning electron microscopy. Hydroxyapatite and silver-doped hydroxyapatite thin films were then sputter deposited on titanium substrates etched at - 700 eV. For silver-doped films, two concentrations of silver ({approx} 0.5 wt.% and {approx} 1.5 wt.%) were used. Silver concentrations in the film were determined using energy dispersive X-ray spectroscopy. Hydroxyapatite film thicknesses were determined by measuring the surface profile using contact profilometry. Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion studies were performed on plain titanium, titanium coated with hydroxyapatite, titanium coated with {approx} 0.5 wt.% silver-doped hydroxyapatite, and titanium coated with {approx} 1.5 wt.% silver-doped hydroxyapatite. Results indicate that less bacteria adhered to surfaces containing hydroxyapatite and silver; further, as the hydroxyapatite films delaminated, silver ions were released which killed bacteria in suspension. - Highlights: Black-Right-Pointing-Pointer We have developed a combination of plasma-based ion implantation and ion beam sputter deposition technique. Black-Right-Pointing-Pointer Silver-doped hydroxyapatite thin films on titanium were developed. Black-Right-Pointing-Pointer The

  6. Effects of an antibacterial membrane on osteoblast-like cells in vitro

    Directory of Open Access Journals (Sweden)

    Ye J

    2011-09-01

    Full Text Available Jun Ye1, Qianqian Yao1, Anchun Mo2, Jing Nie2, Wenwen Liu1, Cui Ye1, Xianji Chen11State Key Laboratory of Oral Diseases, 2Department of Oral Implant, West China College of Stomatology, Sichuan University, Chengdu, People's Republic of ChinaAbstract: Infection around membranes is often found in guided bone regeneration (GBR. The excellent antibacterial properties of Ag-nHA-nTiO2/polyamide-66 (PA66 nanocomposite membranes have been demonstrated previously. The aim of this study was to observe the microstructure of an Ag-nHA-nTiO2/PA66 membrane and its effects on osteoblast-like cells in vitro. An Ag-nHA-nTiO2/PA66 membrane was used in the experimental group, and both nHA/PA66 and expanded poly tetrafluroethylene (e-PTFE membranes were set as control. MG63 osteoblast-like cells were cultured on the three kinds of membrane and tissue culture polystyrene (TCP. The microstructure of the above membranes and the cells adhered on them were detected by scanning electronic microscope (SEM. Cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay, cell viability with a cell viability analyzer, and alkaline phosphatase (ALP activity and Ca2+ concentration of osteoblast-like cell matrix by enzyme-linked immunosorbent assay. SEM showed that both Ag-nHA-nTiO2/PA66 membranes and nHA/PA66 membranes were composed of porous obverse face and smooth opposite face. The e-PTFE membranes showed elliptic surface structure with many tiny lined cracks. The MG63 cells adhered and proliferated well on all three kinds of membranes. Though cell viability on Ag-nHA-nTiO2/PA66 membranes was significantly lower than that of the control groups (P < 0.05, MTT values, ALP activity, and Ca2+ concentration did not differ significantly among the three kinds of membranes (P > 0.05. From these findings, it can be concluded that Ag-nHA-nTiO2/PA66 membranes are as biocompatible as nHA/PA66 membranes and TCP, thus may be applied safely in

  7. Effect of Relative Arrangement of Cationic and Lipophilic Moieties on Hemolytic and Antibacterial Activities of PEGylated Polyacrylates

    Directory of Open Access Journals (Sweden)

    Ashish Punia

    2015-10-01

    Full Text Available Synthetic amphiphilic polymers have been established as potentially efficient agents to combat widespread deadly infections involving antibiotic resistant superbugs. Incorporation of poly(ethylene glycol (PEG side chains into amphiphilic copolymers can reduce their hemolytic activity while maintaining high antibacterial activity. Our study found that the incorporation of PEG has substantially different effects on the hemolytic and antibacterial activities of copolymers depending on structural variations in the positions of cationic centers relative to hydrophobic groups. The PEG side chains dramatically reduced the hemolytic activities in copolymers with hydrophobic hexyl and cationic groups on the same repeating unit. However, in case of terpolymers with cationic and lipophilic groups placed on separate repeating units, the presence of PEG has significantly lower effect on hemolytic activities of these copolymers. PEGylated terpolymers displayed substantially lower activity against Staphylococcus aureus (S. aureus than Escherichia coli (E. coli suggesting the deterring effect of S. aureus’ peptidoglycan cell wall against the penetration of PEGylated polymers. Time-kill studies confirmed the bactericidal activity of these copolymers and a 5 log reduction in E. coli colony forming units was observed within 2 h of polymer treatment.

  8. Toxicity Evaluation of a New Zn-Doped CuO Nanocomposite With Highly Effective Antibacterial Properties.

    Science.gov (United States)

    Mantecca, Paride; Moschini, Elisa; Bonfanti, Patrizia; Fascio, Umberto; Perelshtein, Ilana; Lipovsky, Anat; Chirico, Giuseppe; Bacchetta, Renato; Del Giacco, Luca; Colombo, Anita; Gedanken, Aharon

    2015-07-01

    The increased resistances to conventional antibiotics determine a strong need for new antibacterials, and specific syntheses at the nanoscale promise to be helpful in this field. A novel Zinc-doped Copper oxide nanocomposite (nZn-CuO) has been recently sonochemically synthesized and successfully tested also against multi-drug resistant bacteria. After synthesis and characterization of the physicochemical properties, the new nZn-CuO is here evaluated by the Frog Embyo Teratogenesis Assay-Xenopus test for its toxicological potential and this compared with that of nCuO and nZnO synthesized under the same conditions. No lethal effects are observed, while malformations and growth retardation slightly increase after nZn-CuO exposure. Nevertheless, these effects are smaller than those of nZnO. NP uptake by embryo tissues increase significantly with increasing NP concentrations, while no significant accumulation and adverse effects are seen after exposure to soluble Cu(2+) and Zn(2+) at the concentrations dissolved from the NPs. Key oxidative response genes are upregulated by nZn-CuO, as well as by nCuO and nZnO, suggesting the common mechanism of action. Considering the enhanced biocidal activity shown by the nanocomposite, together with the results presented in this study, we can affirm that the doping of the metal oxide nanoparticles should be considered a useful tool to engineer a safer nano-antibacterial.

  9. Substituted Hydroxyapatites with Antibacterial Properties

    OpenAIRE

    Joanna Kolmas; Ewa Groszyk; Dagmara Kwiatkowska-Różycka

    2014-01-01

    Reconstructive surgery is presently struggling with the problem of infections located within implantation biomaterials. Of course, the best antibacterial protection is antibiotic therapy. However, oral antibiotic therapy is sometimes ineffective, while administering an antibiotic at the location of infection is often associated with an unfavourable ratio of dosage efficiency and toxic effect. Thus, the present study aims to find a new factor which may improve antibacterial activity while also...

  10. Clinical research on the blocking effect of nucleoside analogue on HBV father-to-infant transmission%阻断乙型肝炎病毒父婴传播的临床研究

    Institute of Scientific and Technical Information of China (English)

    曹立华; 李蕴铷; 王守云; 赵培利; 刘志民; 孙绍春; 袁媛; 张继东

    2015-01-01

    目的 研究乙型肝炎病毒(HBV)父婴传播的阻断效果.方法 设观察组、对照组,检测父亲、母亲的肝功能、HBV-M、HBV DNA以进一步分组.检测新生儿出生时静脉血HBVM、HBVDNA以分组观察.观察组共325对,对照组314对.研究夫妇所生的新生儿观察组A301例(24对夫妇妊娠未成功)、对照组A309例入选,两组新生儿均无死亡.对观察组HBV DNA阳性父亲进行核苷类似物抗病毒治疗,所有新生儿出生后接受HBIG、HBVac联合注射或接受单独HBVac注射(新生儿出生时抗-HBs阳性者).结果 观察组A301例新生儿出生时抗HBs阳性288例,无一例HBsAg阳性,无一例HBV DNA阳性.对照组A309例新生儿出生时抗HBs阳性229例,47例HBV DNA阳性,29例HBsAg阳性,两组对比差异有统计学意义.HBV DNA阳性、HBsAg阳性新生儿经联合注射后HBV DNA阴转率59.57%,HBsAg阴转率48.27%.结论 孕前HBV DNA阳性的父亲进行核苷类似物抗病毒治疗使其阴转或较低载量对阻断父婴垂直传播有意义,且是安全的.出生时HBV DNA阳性、HBsAg阳性的新生儿,经联合注射后仍使部分新生儿得到有效的阻断.%Objective To explore the blocking effects of nucleoside analogue treatment of HBV positive father on father-to-infant transmission of HBV infection.Methods A total of 301 couples were enrolled into the observation group and 309 couples were enrolled into the control group,to study the effects of treatment of HBV-positive fathers with nucleotide analog on father-to-infant transmission of HBV infection,the fathers' and mother 's liver function and HBV-markers (HBVM),HBV DNA were determined.The neonatal venous blood HBVM,HBV DNAwere also determined.The HBV DNA positive fathers in the observation group were treated with nucleoside analogue.All the infants received HBIG,HBVac joint injections or received only HBVac when anti-HBs was positive.Results In the observation groupA,anti-HBs was positive in 288 of 301 cases at

  11. Antibacterial and anti-adhesion effects of the silver nanoparticles-loaded poly(L-lactide) fibrous membrane

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shen [Department of Orthopaedics, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Zhao, Jingwen [Orthopedic Institute, Soochow University, 708 Renmin Road, Suzhou, Jiangsu 215007 (China); School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China); Ruan, Hongjiang; Wang, Wei [Department of Orthopaedics, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China); Wu, Tianyi [Department of Orthopaedic Surgery, 2nd Affiliated hospital of Nanjing Medical University, Nanjing Medical University, 121 Jiang Jia Yuan, Nanjing 210011 (China); Cui, Wenguo, E-mail: wgcui80@hotmail.com [Orthopedic Institute, Soochow University, 708 Renmin Road, Suzhou, Jiangsu 215007 (China); School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China); Fan, Cunyi, E-mail: fancunyi888@hotmail.com [Department of Orthopaedics, Shanghai Sixth People' s Hospital, Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Shanghai 200233 (China)

    2013-04-01

    The complications of tendon injury are frequently compromised by peritendinous adhesions and tendon sheath infection. Physical barriers for anti-adhesion may increase the incidence of postoperative infection. This study was designed to evaluate the potential of silver nanoparticles (AgNPs)-loaded poly(L-lactide) (PLLA) electrospun fibrous membranes to prevent adhesion formation and infection. Results of an in vitro drug release study showed that a burst release was followed by sustained release from electrospun fibrous membranes with a high initial silver content. Fewer fibroblasts adhered to and proliferated on the AgNP-loaded PLLA electrospun fibrous membranes compared with pure PLLA electrospun fibrous membrane. In the antibacterial test, the AgNP-loaded PLLA electrospun fibrous membranes can prevent the adhesion of Gram-positive Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa. Taken together, these results demonstrate that AgNP-loaded PLLA electrospun fibrous membranes have the convenient practical medical potential of reduction of infection and adhesion formation after tendon injury. - Highlights: ► Silver nanoparticles are directly electrospun into PLLA fibrous membrane. ► Long-lasting release of Ag + ions is achieved. ► Cytotoxicity of silver ions benefits the anti-proliferation of physical barriers. ► Broad anti-microbial effect of drug-loaded fibrous membrane is revealed. ► Antibacterial and anti-adhesion effects of the physical barriers are combined.

  12. Synthesis of Nanosilver Particles in the Texture of Bank Notes to Produce Antibacterial Effect

    Science.gov (United States)

    Lari, Mohammad Hossein Asadi; Esmaili, Vahid; Naghavi, Seyed Mohammad Ebrahim; Kimiaghalam, Amir Hossein; Sharifaskari, Emadaldin

    Silver particles show antibacterial and antiseptic properties at the nanoscale. Such properties result from an alteration in the binding capacity of silver atoms in bits of less than 6.5nm which enables them to kill harmful organisms. Silver nanoparticles are now the most broadly used agents in the area of nanotechnology after carbon nanotubes. Given that currency bills are one of the major sources of bacterial disseminations and their contamination has recently been nominated as a critical factor in gastrointestinal infections and possibly colon cancers, here we propose a new method for producing antibacterial bank notes by using silver nanoparticles. Older bank notes are sprayed with acetone to clean the surface. The bank note is put into a petri-dish containing a solution of silver nitrate and ammonia so that it is impregnated. The bank notes are then reduced with the formaldehyde gas, which penetrates its texture and produces silver nanoparticles in the cellulose matrix. The side products of the reactions are quickly dried off and the procedure ends with the drying of the bank note. The transmission electron microscope (TEM) images confirmed the nanoscale size range for the formed particles while spectroscopy methods, such as XRD, provided proof for the metallic nature of the particles. Bacterial challenge tests then showed that no colonies of the three tested bacterium (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa survived on the sample after a 72h incubation period. This study has provided a method for synthesizing silver NPs directly into the texture of fabrics and textiles (like that of bank notes) which can result in lower production costs, making the use of silver NPs economically beneficial. The method, specifically works on the fabric of bank notes, suggesting a method to tackle the transmission of bacteria through bank notes. Moreover, this study is a testament to the strong antibacterial nature of even low concentrations of

  13. Using UHPLC Q-Trap/MS as a complementary technique to in-depth mine UPLC Q-TOF/MS data for identifying modified nucleosides in urine.

    Science.gov (United States)

    Lu, Zhiwei; Wang, Qing; Wang, Meiling; Fu, Shuang; Zhang, Qingqing; Zhang, Zhixin; Zhao, Huizhen; Liu, Yuehong; Huang, Zhenhai; Xie, Ziye; Yu, Honghong; Gao, Xiaoyan

    2017-03-12

    Modified nucleosides, metabolites of RNA, are potential biomarkers of cancer before the appearance of morphological abnormalities. It is of great significance to comprehensively detect and identify nucleosides in human urine for discovery of cancer biomarkers. However, the lower abundance, the greater polarity and the matrix effects make it difficult to detect urinary nucleosides. In this paper, an integrated method consisted of sample preparation followed by ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC Q-TOF/MS) detection and primary identification, then ultra-high performance liquid chromatography coupled with hybrid triple quadrupole linear ion trap mass spectrometer (UHPLC Q-Trap/MS) further identification and validation were introduced. Firstly, to enrich the nucleosides and eliminate the urine matrix effects, different sorbent materials of solid phase extraction (SPE) and the elution conditions were screened. Secondly, UPLC Q-TOF/MS was used to acquire mass data in MS(E) mode. The structural formulas of nucleosides in urine sample were primarily identified according to retention time, accurate mass precursor ions and fragment ions from in-house database and online database. Thirdly, the preliminary identified nucleoside structures lacking of characteristic fragment ions were verified by UHPLC Q-Trap/MS in multiple reaction monitoring trigger enhanced product ion scan (MRM-EPI) and neutral loss scan (NL). At last, phenylboronic acid (PBA)-based SPE was utilized due to its higher MS signal and weaker matrix effects under optimized extraction conditions. Fifty-five nucleosides were primarily identified by UPLC Q-TOF/MS, among which 50 nucleosides were confirmed by UHPLC Q-Trap/MS. Five nucleosides, namely 4',5'-didehydro-5'-deoxyadenosine, 4',5'-didehydro-5'-deoxyinosine, isonicotinamide riboside, peroxywybutosine and hydroxywybutosine, were found from urine for the first time. The results will expand the Human

  14. Biogenic nanoparticles bearing antibacterial activity and their synergistic effect with broad spectrum antibiotics: Emerging strategy to combat drug

    Directory of Open Access Journals (Sweden)

    Syed Baker

    2017-01-01

    Full Text Available The present study emphasizes on synthesis of bimetallic silver–gold nanoparticles from cell free supernatant of Pseudomonas veronii strain AS41G inhabiting Annona squamosa L. The synthesized nanoparticles were characterized using hyphenated techniques with UV–Visible spectra ascertained absorbance peak between 400 and 800 nm. Possible interaction of biomolecules in mediating and stabilization of nanoparticles was depicted with Fourier transform infrared spectroscopy (FTIR. X-ray diffraction (XRD displayed Bragg’s peak conferring the 100, 111, 200, and 220 facets of the face centered cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. Size and shape of the nanoparticles were determined using Transmission electron microscopy (TEM microgram with size ranging from 5 to 50 nm forming myriad shapes. Antibacterial activity of nanoparticles against significant human pathogens was conferred with well diffusion assay and its synergistic effect with standard antibiotics revealed 87.5% fold increased activity with antibiotic “bacitracin” against bacitracin resistant strains Bacillus subtilis, Escherichia coli and Klebsiella pneumoniae followed by kanamycin with 18.5%, gentamicin with 11.15%, streptomycin with 10%, erythromycin with 9.7% and chloramphenicol with 9.4%. Thus the study concludes with biogenic and ecofriendly route for synthesizing nanoparticles with antibacterial activity against drug resistant pathogens and attributes growing interest on endophytes as an emerging source for synthesis of nanoparticles.

  15. Antibacterial study of the medium chain fatty acids and their 1-monoglycerides: individual effects and synergistic relationships.

    Science.gov (United States)

    Batovska, Daniela I; Todorova, Iva T; Tsvetkova, Iva V; Najdenski, Hristo M

    2009-01-01

    The antibacterial activity of the medium chain fatty acids and their 1-monoglycerides was evaluated towards several Gram-positive strains belonging to the genera Staphylococcus, Corynebacterium, Bacillus, Listeria and Streptococcus. The 1-monoglycerides were more active than the fatty acids with monolaurin being the most active compound. Interesting effects were observed when the streptococcal strain Streptococcus pyogenes was used as a test microorganism. First, blocking of the hydroxyl groups of the glycerol moiety of monolaurin led to a compound with remarkable antibacterial activity (MIC, 3.9 microg/ml). Secondly, synergistic relationships were observed between monolaurin and monocaprin as well as between monolaurin and the poorly active lauric acid when their two component mixtures were examined. The mixtures in which one of the components was 2-fold more predominant than the other one were much more active than the pure components taken individually. Moreover, the presence of the components in ratio 1:1 was disadvantageous. Synergistic relationships were also found between monolaurin and monomyristin towards Staphylococcus aureus 209 when monomyristin was in the same quantity as monolaurin or in shortage.

  16. Effect of Zirconium Dioxide Nanoparticles as a Mordant on Properties of Wool with Thyme: Dyeing, Flammability and Antibacterial

    Directory of Open Access Journals (Sweden)

    M. Taheri

    2015-03-01

    Full Text Available In this research, the zirconium dioxide nanoparticle was synthesized and the effect of these particles as a mordant on properties of wool fabric in dying process with a natural dye,also flammability and antibacterial properties were studied. The wool fabrics were treated with different concentrations of zirconium dioxide nanoparticles including 1, 3, 6 and 9% o.w.f. and the dyeing process was carried out on the fabrics in the states before, simultaneously and after mordanting with Thyme. The chemical characteristics and the changes induced by zirconium were investigated by Fourier-transform infrared spectra (FTIR.The influence of the amount of nano-ZrO2 and the type of mordanting treatment on dye absorbency were studied by reflectance spectrophotometer (RS. Flammability of samples was investigated by horizontal flammability test (HFT.The antibacterial properties were determined by reduction growth of a Gram-negative bacterium E. coli and a Gram-positive bacterium Staphylococcus aureus. The surfaces of untreated and treated fabrics were evaluated by scanning electron microscopy to observe the morphological changes.

  17. A murine model to study the antibacterial effect of copper on infectivity of Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Sharan, Riti; Chhibber, Sanjay; Reed, Robert H

    2011-01-01

    This study investigated the effect of copper as an antibacterial agent on the infectivity of Salmonella enterica serovar Typhimurium. Mice were infected orally with a standardized dose of unstressed Salmonella Typhimurium and copper-stressed cells of Salmonella Typhimurium. Bacterial counts in ileum, blood, liver and spleen were observed up to 168 h under normal aerobic conditions. Serum sensitivity, phagocytosis, malondialdehyde levels and histopathology were studied for both set of animals. A decreased bacterial count in the organs with mild symptoms of infection and a complete recovery by 48 h was observed in mice infected with copper-stressed bacteria. Histopathological examination of ileum tissue demonstrated regeneration of damaged tissue post-infection with copper-stressed bacteria and no malondialdehyde levels were detected after 24 h in ileum, spleen and liver. Exposure to copper sensitized Salmonella Typhimurium to the lytic action of serum and intracellular killing by peritoneal macrophages. It can be concluded that copper stress confers a decrease in the infectivity of healthy Salmonella Typhimurium in normal mice. This study highlights the significance of use of copper as an antibacterial agent against Salmonella Typhimurium in reducing the risk of incidence of Salmonella infections from contaminated water.

  18. A Murine Model to Study the Antibacterial Effect of Copper on Infectivity of Salmonella Enterica Serovar Typhimurium

    Directory of Open Access Journals (Sweden)

    Robert H. Reed

    2010-12-01

    Full Text Available This study investigated the effect of copper as an antibacterial agent on the infectivity of Salmonella enterica serovar Typhimurium. Mice were infected orally with a standardized dose of unstressed Salmonella Typhimurium and copper-stressed cells of Salmonella Typhimurium. Bacterial counts in ileum, blood, liver and spleen were observed up to 168 h under normal aerobic conditions. Serum sensitivity, phagocytosis, malondialdehyde levels and histopathology were studied for both set of animals. A decreased bacterial count in the organs with mild symptoms of infection and a complete recovery by 48 h was observed in mice infected with copper-stressed bacteria. Histopathological examination of ileum tissue demonstrated regeneration of damaged tissue post-infection with copper-stressed bacteria and no malondialdehyde levels were detected after 24 h in ileum, spleen and liver. Exposure to copper sensitized Salmonella Typhimurium to the lytic action of serum and intracellular killing by peritoneal macrophages. It can be concluded that copper stress confers a decrease in the infectivity of healthy Salmonella Typhimurium in normal mice. This study highlights the significance of use of copper as an antibacterial agent against Salmonella Typhimurium in reducing the risk of incidence of Salmonella infections from contaminated water.

  19. ANTIBACTERIAL AND BIOCHEMICAL EFFECTS OF ETHANOL LEAF EXTRACT OF SENNA HIRSUTA MILL USING ANIMAL MODEL-MICE

    Directory of Open Access Journals (Sweden)

    Fred Coolborn Akharaiyi

    2015-02-01

    Full Text Available This study was carried out to investigate the in-vitro and in-vivo antibacterial and biochemical activities of 50, 100 and 200mg.mL-1 concentrations of ethanol leaf extract of Senna hirsuta (hairy senna against seven human pathogenic bacteria species namely: Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecium, Bacillus cereus and Salmonella typhi. The in-vitro bioassay revealed the leaf extracts of valuable antibacterial activity where zones of inhibition ranging from 12.1mm to 39.1mm were observed on the test bacteria species. Among the test bacteria, K. pneumoniae was the most inhibited and S. typhi the least inhibited. On mice infection with the bacteria species for three days, decrease in weight of mice was observed. The in-vivo therapeutic use of the extracts in mice infected with the bacteria pathogens resulted to weight gain of the mice and other physiological changes that indicated health improvement of the mice and was also of hepatoprotective potential. The in-vivo antioxidant assay exhibited satisfactory therapeutic effects where improvement in aspartate aminotransferase (AST, alanine aminotransferase (ALT, and alkaline phosphatase (ALP status of mice was observed on comparing results of the positive and negative controls.

  20. C5-Modified nucleosides exhibiting anticancer activity.

    Science.gov (United States)

    Lee, Yoon-Suk; Park, Sun Min; Kim, Hwan Mook; Park, Song-Kyu; Lee, Kiho; Lee, Chang Woo; Kim, Byeang Hyean

    2009-08-15

    We describe (i) a simple method for the synthesis of C5-modified nucleosides from 5-iodo-2'-deoxyuridine and (ii) their activity against six types of human cancer cell lines (HCT15, MM231, NCI-H23, NUGC-3, PC-3, ACHN). We generated nitrile oxides in situ from oximes using a commercial bleaching agent; their cycloadditions with 5-ethynyl-2'-deoxyuridine yielded isoxazole derivatives possessing activity against the cancer cell lines. We synthesized several azides from benzylic bromides and their click reactions with 5-ethynyl-2'-deoxyuridine provided triazole derivatives.

  1. Hybridization accompanying FRET event in labeled natural nucleoside-unnatural nucleoside containing chimeric DNA duplexes.

    Science.gov (United States)

    Bag, Subhendu Sekhar; Das, Suman K; Pradhan, Manoj Kumar; Jana, Subhashis

    2016-09-01

    Förster resonance energy transfer (FRET) is a highly efficient strategy in illuminating the structures, structural changes and dynamics of DNA, proteins and other biomolecules and thus is being widely utilized in studying such phenomena, in designing molecular/biomolecular probes for monitoring the hybridization event of two single stranded DNA to form duplex, in gene detection and in many other sensory applications in chemistry, biology and material sciences. Moreover, FRET can give information about the positional status of chromophores within the associated biomolecules with much more accuracy than other methods can yield. Toward this end, we want to report here the ability of fluorescent unnatural nucleoside, triazolylphenanthrene ((TPhen)BDo) to show FRET interaction upon hybridization with fluorescently labeled natural nucleosides, (Per)U or (OxoPy)U or (Per)U, forming two stable chimeric DNA duplexes. The pairing selectivity and the thermal duplex stability of the chimeric duplexes are higher than any of the duplexes with natural nucleoside formed. The hybridization results in a Förster resonance energy transfer (FRET) from donor triazolylphenanthrene of (TPhen)BDo to acceptor oxopyrene of (OxoPy)U and/or to perylene chromophore of (Per)U, respectively, in two chimeric DNA duplexes. Therefore, we have established the FRET process in two chimeric DNA duplexes wherein a fluorescently labeled natural nucleoside ((OxoPy)U or (Per)U) paired against an unnatural nucleoside ((TPhen)BDo) without sacrificing the duplex stability and B-DNA conformation. The hybridization accompanying FRET event in these classes of interacting fluorophores is new. Moreover, there is no report of such designed system of chimeric DNA duplex. Our observed phenomenon and the design can potentially be exploited in designing more of such efficient FRET pairs for useful application in the detection and analysis of biomolecular interactions and in material science application.

  2. Evaluation of antibacterial activity and synergistic effect between antibiotic and the essential oils of some medicinal plants

    Institute of Scientific and Technical Information of China (English)

    Fadila Moussaoui; Tajelmolk Alaoui

    2016-01-01

    Objective:To demonstrate the in vitro antibacterial properties of five essential oils against ten bacterial strains and study the synergistic effect of the combination of essential oils with standard antibiotics.Methods:Origanum compactum,Chrysanthemum coronarium,Thymus willdenowii Boiss,Melissa officinalis and Origanum majorana L.were used alone and combined used with standard antibiotics to evaluate their antimicrobial activities.The disk diffusion method was employed.Results:The results showed that the combined application of the essential oils of the plants with antibiotics led to a synergistic effect in some cases,but antagonistic effect was also observed in some bacteria.Conclusions:This study shows that the combination of essential oils of the five plants with antibiotics may be useful in the fight against emerging microbial drug resistance.

  3. Evaluation of antibacterial activity and synergistic effect between antibiotic and the essential oils of some medicinal plants

    Institute of Scientific and Technical Information of China (English)

    Fadila Moussaoui; Tajelmolk Alaoui

    2016-01-01

    Objective: To demonstrate the in vitro antibacterial properties of five essential oils against ten bacterial strains and study the synergistic effect of the combination of essential oils with standard antibiotics. Methods: Origanum compactum, Chrysanthemum coronarium, Thymus willdenowii Boiss, Melissa officinalis and Origanum majorana L. were used alone and combined used with standard antibiotics to evaluate their antimicrobial activities. The disk diffusion method was employed. Results: The results showed that the combined application of the essential oils of the plants with antibiotics led to a synergistic effect in some cases, but antagonistic effect was also observed in some bacteria. Conclusions: This study shows that the combination of essential oils of the five plants with antibiotics may be useful in the fight against emerging microbial drug resistance.

  4. [Current status and further prospects of dental resin-based materials with antibacterial properties].

    Science.gov (United States)

    Shi, X; Lu, H B; Mao, J; Gong, S Q

    2016-09-01

    The mode of dental antibacterial resin-based materials can be divided into two types, namely, single and combined antibacterial mode. With regard to single antibacterial mode, only one kind of antibacterial agent is added into the resin, which can be released or act as contacting antibacterial agent. The single mode resin has limitation in sterilization methods and effect. As for combined antibacterial mode, it is a combination of different types of biocides and thus maximizes the sterilizing effect, including the releasing antibacterial agent incorporated with the contacting antibacterial agent or antibacterial agents combined with calcium compound possessing biological mineralization function. In this paper, current status and further prospects of dental resin-based materials with antibacterial properties are reviewed from the perspectives of single and combined antibacterial modes to provide guidance for dental antibacterial resin material research.

  5. Antibacterial Activity of Culture Extracts of Penicillium chrysogenum PCL501: Effects of Carbon Sources

    Directory of Open Access Journals (Sweden)

    Blessing M. Onyegeme-Okerenta

    2009-05-01

    Full Text Available Penicillium chrysogenum PCL501 produced β-lactam antibiotics when fermented with different agro-wastes: cassava shavings, corncob, sawdust and sugarcane pulp. In vitro antibacterial activity of the culture extracts was tested against four clinical bacterial isolates, namely, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. All the culture extracts and standard drug (commercial Benzyl Penicillin inhibited the growth B. subtilis and E. coli; the potency varied with carbon source. Antibacterial activity of extracts from cultures containing cassava shavings and sugarcane pulp was comparable with that of the standard drug. The MIC against the susceptible organisms was 0.20mg/ml for the standard drug and ranged from 0.40 to 1.50mg/ml for the culture extracts. Neither the culture extracts nor the standard drug inhibited K. pneumoniae and P. aeruginosa; the bacterial strains produced β-lactamase enzymes. Cassava shavings and sugarcane pulp are indicated as suitable cheap carbon sources for the production of antibiotics by Penicillium chrysogenum PCL501.

  6. Antibacterial and COX-1 Inhibitory Effect of Medicinal Plants from the Pamir Mountains, Afghanistan

    Directory of Open Access Journals (Sweden)

    Anne S. Jeppesen

    2012-10-01

    Full Text Available Plants used to treat inflammatory ailments, pain, fever and infections in the Pamir Mountains in northeastern Afghanistan, were tested for antibacterial and COX-1 inhibitory activity. Water and ethanol extracts of 20 species were tested for antibacterial activity against two gram positive and two gram negative bacteria. The ethanol extract of Arnebia guttata inhibited Staphylococcus aureus with a MIC of 6 µg/mL. Water and ethanol extracts of Ephedra intermedia and the ethanol extracts of Lagochilus cabulicus and Peganum harmala inhibited Staphylococcus aureus at 0.5 mg/mL, and the P. harmala extract further inhibited the growth of Bacillus subtilis and E. coli, also with MICs of 0.5 mg/mL. Ethanol extracts of Artemisia persica (IC50: 0.5 µg/mL, Dragocephalum paulsenii (IC50: 0.5 µg/mL, Ephedra intermedia (IC50: 3.8 µg/mL, Hyoscyamus pusillus, Nepeta parmiriensis (IC50: 0.7 µg/mL and Rumex patientia subsp. pamiricus (IC50: 3.5 µg/mL exhibited COX-1 inhibitory activity. The observed in vitro activities support the use of some of the plant species in the traditional medicine systems of the Pamir Mountains.

  7. In vitro antibacterial effect of Withania somnifera root extract on Escherichia coli

    Directory of Open Access Journals (Sweden)

    Mamta Kumari

    2015-01-01

    Full Text Available Aim: The aim was to investigate antibacterial activity of Withania somnifera (Ashwagandha, an Indian traditional medicinal plant against Escherichia coli O78, a pathogenic strain. Materials and Methods: Two-fold serial dilutions of 20% aqueous W. somnifera root (WSR extract were inoculated with E. coli O78 @ 1x107 colony forming units grown in nutrient broth. Following inoculation, turbidity optical density was measured by spectrophotometer at 600 nm in all the tubes at 0, 2, 4, 6 and 8 h of incubation at 37°C. Result: The results revealed that the maximum inhibition of bacterial growth was observed at 1:8 dilution of WSR extract. The highest dilution of the extract that showed inhibited growth of the test organism when compared with control was 1:16. Therefore, the minimum inhibitory concentration of aqueous extract of WSR is 1:16. Conclusion: It is concluded that WSR possessed good antibacterial activity, confirming the great potential of bioactive compounds and its rationalizing use in health care.

  8. Anti-bacterial effects of enzymatically-isolated sialic acid from glycomacropeptide in a Helicobacter pylori-infected murine model

    Science.gov (United States)

    Noh, Hye-Ji; Koh, Hong Bum; Kim, Hee-Kyoung; Cho, Hyang Hyun

    2017-01-01

    BACKGROUND/OBJECTIVES Helicobacter pylori (H. pylori) colonization of the stomach mucosa and duodenum is the major cause of acute and chronic gastroduodenal pathology in humans. Efforts to find effective anti-bacterial strategies against H. pylori for the non-antibiotic control of H. pylori infection are urgently required. In this study, we used whey to prepare glycomacropeptide (GMP), from which sialic acid (G-SA) was enzymatically isolated. We investigated the anti-bacterial effects of G-SA against H. pylori in vitro and in an H. pylori-infected murine model. MATERIALS/METHODS The anti-bacterial activity of G-SA was measured in vitro using the macrodilution method, and interleukin-8 (IL-8) production was measured in H. pylori and AGS cell co-cultures by ELISA. For in vivo study, G-SA 5 g/kg body weight (bw)/day and H. pylori were administered to mice three times over one week. After one week, G-SA 5 g/kg bw/day alone was administered every day for one week. Tumor necrosis factor-α (TNF-α), IL-1β, IL-6, and IL-10 levels were measured by ELISA to determine the anti-inflammatory effects of G-SA. In addition, real-time PCR was performed to measure the genetic expression of cytotoxin-associated gene A (cagA). RESULTS G-SA inhibited the growth of H. pylori and suppressed IL-8 production in H. pylori and in AGS cell co-cultures in vitro. In the in vivo assay, administration of G-SA reduced levels of IL-1β and IL-6 pro-inflammatory cytokines whereas IL-10 level increased. Also, G-SA suppressed the expression of cagA in the stomach of H. pylori-infected mice. CONCLUSION G-SA possesses anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect in an experimental H. pylori-infected murine model. G-SA has potential as an alternative to antibiotics for the prevention of H. pylori infection and H. pylori-induced gastric disease prevention. PMID:28194260

  9. THE ANTIBACTERIAL EFFECT OF SOME MEDICINAL PLANTS (INULA VISCOSA, ANACYCLUS VALENTINUS AND THEIR SYNERGISTIC INTERACTION WITH ANTIBIOTIC DRUGS

    Directory of Open Access Journals (Sweden)

    K. Side Larbi

    2016-05-01

    Full Text Available With the emergence of multidrug-resistant organisms, combining medicinal plants with synthetic medicines against resistant bacteria becomes necessary. In this study, Synergism between plant extracts (methanolic extract and essential oils of Inula viscosa and Anacyclus valentinus and two commonly used antibiotics (gentamycin, oxacillin were investigated on three bacterian strains (E. coli, Bacillus subtilis, Staphylococcus aureus. In the first time, the antibacterial effect of extracts alone was tested against 7 strains by disc diffusion and microdilution methods. The minimum inhibitory concentrations of methanolic extracts ranged between 6.25 and 50mg/ml while that of the essential oils varied between 12.5 and 100µL/mL. Interactions extracts /antibiotics and extracts/extracts by checkboard. The results show that the synergistic effect of combinations plant extracts/antibiotics was more important than extracts/extracts.

  10. Antibacterial activity in adhesive dentistry: a literature review.

    Science.gov (United States)

    Shafiei, Fereshteh; Memarpour, Mahtab

    2012-01-01

    This literature review summarizes the published research regarding the antibacterial agents used in adhesive dentistry. This article provides information about the clinical applications, beneficial effects, and possible disadvantages of antibacterials when used in various bonding situations.

  11. Antibacterial effect of light emitting diodes of visible wavelengths on selected foodborne pathogens at different illumination temperatures.

    Science.gov (United States)

    Ghate, Vinayak S; Ng, Kheng Siang; Zhou, Weibiao; Yang, Hyunsoo; Khoo, Gek Hoon; Yoon, Won-Byong; Yuk, Hyun-Gyun

    2013-09-16

    The antibacterial effect of light emitting diodes (LEDs) in the visible region (461, 521 and 642 nm) of the electromagnetic spectrum was investigated on Escherichia coli O157:H7, Salmonella typhimurium, Listeria monocytogenes and Staphylococcus aureus. The irradiances of the 461, 521 and 642 nm LEDs were 22.1, 16 and 25.4 mW/cm², respectively. Bacterial cultures suspended in tryptic soy broth were illuminated by 10-watt LEDs at a distance of 4.5 cm for 7.5h at 20, 15 and 10 °C. Regardless of the bacterial strains, bacterial inactivation was observed with the range of 4.6-5.2 logCFU/ml at 10 and 15 °C after illumination with the 461 nm LED, while illumination with the 521 nm LED resulted in only 1.0-2.0 log reductions after 7.5h. On the other hand, no antibacterial effect was observed using the 642 nm LED treatment. The photodynamic inactivation by 461 and 521 nm LEDs was found to be greater at the set temperatures of 10 and 15 °C than at 20 °C. The D-values for the four bacterial strains at 10 and 15 °C after the illumination of 461 nm LED ranged from 1.29 to 1.74 h, indicating that there was no significant difference in the susceptibility of the bacterial strains to the LED illumination between 10 and 15 °C, except for L. monocytogenes. Regardless of the illumination temperature, sublethal injury was observed in all bacterial strains during illumination with the 461 and the 521 nm LED and the percentage of injured cells increased as the treatment time increased. Thus, the results show that the antibacterial effect of the LEDs was highly dependent on the wavelength and the illumination temperature. This study suggests the potential of 461 and 521 nm LEDs in combination with chilling to be used as a novel food preservation technology.

  12. Rapid green synthesis of silver nanoparticles from Chrysanthemum indicum L and its antibacterial and cytotoxic effects: an in vitro study

    Directory of Open Access Journals (Sweden)

    Arokiyaraj S

    2014-01-01

    Full Text Available Selvaraj Arokiyaraj,1 Mariadhas Valan Arasu,2 Savariar Vincent,3 Nyayirukannaian Udaya Prakash,4 Seong Ho Choi,5 Young-Kyoon Oh,1 Ki Choon Choi,2 Kyoung Hoon Kim1,61Department of Animal Nutrition and Physiology, National Institute of Animal Science, Rural Development Administration, Suwon, Republic of Korea; 2Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Seonghwan-Eup, Cheonan-Si, Chungnam, Republic of Korea; 3Center for Environmental Research and Development, Loyola College, Chennai, India; 4Research and Development, Vel Tech Dr RR and Dr SR Technical University, Chennai, India; 5Department of Animal Science, Chungbuk National University, Chungbuk, Republic of Korea; 6Department of Animal Science, Seoul National University, Pyeongchang, Republic of KoreaAbstract: The present work reports a simple, cost-effective, and ecofriendly method for the synthesis of silver nanoparticles (AgNPs using Chrysanthemum indicum and its antibacterial and cytotoxic effects. The formation of AgNPs was confirmed by color change, and it was further characterized by ultraviolet–visible spectroscopy (435 nm. The phytochemical screening of C. indicum revealed the presence of flavonoids, terpenoids, and glycosides, suggesting that these compounds act as reducing and stabilizing agents. The crystalline nature of the synthesized particles was confirmed by X-ray diffraction, as they exhibited face-centered cubic symmetry. The size and morphology of the particles were characterized by transmission electron microscopy, which showed spherical shapes and sizes that ranged between 37.71–71.99 nm. Energy-dispersive X-ray spectroscopy documented the presence of silver. The antimicrobial effect of the synthesized AgNPs revealed a significant effect against the bacteria Klebsiella pneumonia, Escherichia coli, and Pseudomonas aeruginosa. Additionally, cytotoxic assays showed no toxicity of AgNPs toward 3T3 mouse embryo

  13. Analyzing the antibacterial effects of food ingredients : model experiments with allicin and garlic extracts on biofilm formation and viability of Staphylococcus epidermidis

    NARCIS (Netherlands)

    Wu, Xueqing; Santos, Regiane R; Fink-Gremmels, Johanna

    2015-01-01

    To demonstrate different effects of garlic extracts and their main antibiotic substance allicin, as a template for investigations on the antibacterial activity of food ingredients. Staphylococcus epidermidis ATCC 12228 and the isogenic biofilm-forming strain ATCC 35984 were used to compare the activ

  14. Phytochemical screening, antibacterial and free radical scavenging effects of Artemisia nilagirica, Mimosa pudica and Clerodendrum siphonanthus-An in-vitro study

    Institute of Scientific and Technical Information of China (English)

    Arokiyaraj S; Sripriya N; Bhagya R; Radhika B; Prameela L; Udayaprakash NK

    2012-01-01

    Objective: To evaluate methanolic extracts of leaves of Artemisia nilagirica, Mimosa pudica and Clerodendrum siphonanthus for phytochemical analysis, antibacterial activity and free radical scavenging activity. Methods: Antibacterial activity was performed by disc diffusion method against two gram positive and four gram negative strains. Free radical scavenging potential was evaluated using total antioxidant activity (thiocyanate method) and diphenyl-picryl-hydrazyl (DPPH) assay. Results: Results of the present study showed that Clerodendrum siphonanthus exhibited significant antibacterial effect against Klebsiella pneumoniae (30 mm), Proteus mirabilis (16 mm), Salmonella typhi (16 mm), Staphylococcus aureus (12 mm), Escherichia coli (11.5 mm) and Bacillus subtilis (10 mm). Mimosa pudica and Artemisia nilagirica showed good antibacterial effects. Clerodendrum siphonanthus was found to be extremely effective in scavenging lipid peroxide (IC50 8 mg/mL) and DPPH radicals (IC50 7 mg/mL), whereas Artemisia nilagirica andMimosa pudica showed moderate activity. Phytochemical analysis of these plants revealed presence of tannins, alkaloids, flavanoids, terpenoids and glycosides. Conclusions: This study showed that Artemisia nilagirica, Mimosa pudica and Clerodendrum siphonanthus may serve as a potential agent for new therapeutics.

  15. HONEYDEW HONEY: CORRELATIONS BETWEEN CHEMICAL COMPOSITION, ANTIOXIDANT CAPACITY AND ANTIBACTERIAL EFFECT

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    OTILIA BOBIS

    2013-12-01

    Full Text Available Selected physico-chemical parameters, total polyphenols, flavonoids, antioxidant and antibacterial activity of honeydew honey samples from Romanian were determined. Regarding the chemical composition, analysed honey samples framed in this type of honey, phenolic content, determined as gallic acid equivalents, presented a mean value of 116.45mg GAE/100 g honey. Total flavonoid content expressed as quercetin equivalents, was 1.53 mg in honeydew honey. Antioxidant activity expressed as % inhibition of a solution of DPPH, ranged between 47.84 and 62.99%. The concentration of honey that inhibit with 50% the DPPH solution was established to be 16.16%. 10 strains of Staphylococcus aureus presented different inhibition percentages when were treatred with a solution of honey. In conclusion, Honeydew honey could be recommended to complement other polyphenol source in human diet and also used in medical treatment.

  16. Investigating the Antibacterial Effects of Plant Extracts on Pseudomonas aeruginosa and Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jahani

    2016-04-01

    Full Text Available Background Scientists are seeking an appropriate alternative method for curing infections caused by resistant bacteria, since drug resistance is continually increasing. Objectives This research aims to discover the function of some medicine plants on pestiferous Pseudomonas aeruginosa and Escherichia coli in humans. Materials and Methods Bacterial strains were obtained from a standard laboratory. The strains of Pseudomonas aeruginosa ATCC27853 and E.coli ATCC25922 bacteria were used for antimicrobial testing of the extractions. Results Our results showed that Teucrium polium extracts have the minimum density of inhibitory for Escherichia coli, 25 ppm, whereas the maximum of this is for Peganum harmala and Prangos ferulaceae with 100 ppm. The lowest minimum concentration inhibitory value of extracts P. harmala, T. polium, T. pratensis and Rumex was found in 25 ppm against P.aeruginosa. Conclusions The results of our study showed that plant extracts have good antibacterial properties against Pseudomonas aeruginosa and Escherichia coli.

  17. Antibacterial effect of urushiol on E. faecalis as a root canal irrigant

    Science.gov (United States)

    Kim, Sang-Wan

    2017-01-01

    Objectives The purpose of this study was to compare the antibacterial activity of urushiol against Enterococcus faecalis (E. faecalis) to that of NaOCl. Materials and Methods The canals of thirty two single rooted human teeth were instrumented with Ni-Ti files (ProTaper Next X1, X2, X3, Dentsply). A pure culture of E. faecalis ATCC 19433 was prepared in sterile brain heart infusion (BHI) broth. The teeth were submerged in the suspension of E. faecalis and were incubated at 37℃ for 7 days to allow biofilm formation. The teeth were randomly divided into three experimental groups according to the irrigant used, and a negative control group where no irrigant was used (n = 8). Group 1 used physiologic normal saline, group 2 used 6% NaOCl, and group 3 used 10 wt% urushiol solution. After canal irrigation, each sample was collected by the sequential placement of 2 sterile paper points (ProTaper NEXT paper points, size X3, Dentsply). Ten-fold serial dilutions on each vials, and 100 µL were cultured on a BHI agar plate for 8 hours, and colony forming unit (CFU) analysis was done. The data were statistically analyzed using Kruskal-Wallis and Mann-whitney U tests. Results Saline group exhibited no difference in the CFU counts with control group, while NaOCl and urushiol groups showed significantly less CFU counts than saline and control groups (p < 0.05). Conclusions The result of this study suggests 10% urushiol and 6% NaOCl solution had powerful antibacterial activity against E. faecalis when they were used as root canal irrigants. PMID:28194365

  18. Effect of Ti(+4) on in vitro bioactivity and antibacterial activity of silicate glass-ceramics.

    Science.gov (United States)

    Riaz, Madeeha; Zia, Rehana; Saleemi, Farhat; Hussain, Tousif; Bashir, Farooq; Ikhram, Hafeez

    2016-12-01

    A novel glass-ceramic series in (48-x) SiO2-36 CaO-4 P2O5-12 Na2O-xTiO2 (where x=0, 3.5, 7, 10.5 and 14mol %) system was synthesized by crystallization of glass powders, obtained by melt quenching technique. The differential scanning calorimetric analysis (DSC) was used to study the non-isothermal crystallization kinetics of the as prepared glasses. The crystallization behaviour of glasses was analyzed under non-isothermal conditions, and qualitative phase analysis of glass-ceramics was made by X-ray diffraction. The in vitro bioactivity of synthesized glass-ceramics was studied in stimulated body fluid at 37°C under static condition for 24days. The formation of hydroxyl-carbonated apatite layer; evident of bioactivity of the material, was elucidated by XRD, FTIR, AAS, SEM and EDX analysis. The result showed that partial substitution of TiO2 with SiO2 negatively influenced bioactivity; it decreased with increase in concentration of TiO2. As Ti(+4) having stronger field strength as compared to Si(+4) so its replacement became the cause for reduction in degradation that in turn improved the chemical stability. The compressive strength was also enhanced with progress addition of TiO2 in the system. The antibacterial properties were examined against Staphylococcus Epidermidis. Strong antibacterial efficacy was observed with the addition of TiO2 in the system.

  19. Effects of a novel carbocyclic analog of pyrrolo[2,3-d]pyrimidine nucleoside on pleiotropic induction of cell death in prostate cancer cells with different androgen responsiveness.

    Science.gov (United States)

    Suh, Hyewon; Choi, Ko-woon; Lee, Jongbok; Ryou, Chongsuk; Rhee, Hakjune; Lee, Chul-Hoon

    2016-02-15

    Prostate cancer is the most frequently diagnosed cancer and is one of the leading causes of male cancer death in the world. Recently, in the course of our screening for a novel anticancer compound, we synthesized carbocyclic analogs of pyrrolo[2,3-d]pyrimidine nucleoside; compounds 5, and 6. In the current study, we report the effects of compound 5 on pleiotropic induction of cell death via up-regulation of AR-associated p21(Cip1) protein in prostate cancer cells with different androgen responsiveness, such as LNCaP (androgen-dependent and -sensitive), LNCaP(C4-2) (androgen-independent and -sensitive; androgen-refractory), and DU145 (androgen-independent and -insensitive) cells. The treatment of LNCaP cells with 6 μM compound 5 for 24 h stimulated the androgen receptor (AR) activity and dramatically up-regulated transcription (56-fold) of p21(Cip1), which, in turn, induces typical apoptosis in the cells. However, induction of apoptosis through up-regulation (23-fold) of AR-associated p21(Cip1) achieved in LNCaP(C4-2) cells was possible by intensive cell treatment with compound 5 (9 μM, 48 h), because the cells are less sensitive and independent to androgen than LNCaP cells. Furthermore, 6 μM compound 5-treated DU145 cells, which exhibit extremely low AR activation due to no androgen responsiveness and dependency, showed neither up-regulation of p21(Cip1) nor apoptotic induction. Instead, a different type of cell death, autophagy-like death through the LC3B-associated autophagosome formation, was obviously induced in DU145 cells. Taken together, our results suggest that pleiotropic induction of prostate cancer cell death by compound 5 is determined by how efficiently and how abundantly androgen-dependent activation of the AR occurs, whereas compound 6 shows no induction of apoptosis in LNCaP cells.

  20. From the traditional Chinese medicine plant Schisandra chinensis new scaffolds effective on HIV-1 reverse transcriptase resistant to non-nucleoside inhibitors.

    Science.gov (United States)

    Xu, Lijia; Grandi, Nicole; Del Vecchio, Claudia; Mandas, Daniela; Corona, Angela; Piano, Dario; Esposito, Francesca; Parolin, Cristina; Tramontano, Enzo

    2015-04-01

    HIV-1 reverse transcriptase (RT) is still an extremely attractive pharmaceutical target for the identification of new inhibitors possibly active on drug resistant strains. Medicinal plants are a rich source of chemical diversity and can be used to identify novel scaffolds to be further developed by chemical modifications. We investigated the ability of the main lignans from Schisandra chinensis (Turcz.) Baill. fruits, commonly used in Traditional Chinese Medicine, to affect HIV-1 RT functions. We purified 6 lignans from Schisandra chinensis fruits and assayed their effects on HIV-1 RT and viral replication. Among the S. chinensis fruit lignans, Schisandrin B and Deoxyschizandrin selectively inhibited the HIV-1 RT-associated DNA polymerase activity. Structure activity relationship revealed the importance of cyclooctadiene ring substituents for efficacy. In addition, Schisandrin B was also able to impair HIV-1 RT drug resistant mutants and the early phases of viral replication. We identified Schisandrin B and Deoxyschizandrin as new scaffold for the further development of novel HIV-1 RT inhibitors.

  1. Structural characterization, antibacterial and catalytic effect of iron oxide nanoparticles synthesised using the leaf extract of Cynometra ramiflora

    Science.gov (United States)

    Groiss, Silvia; Selvaraj, Raja; Varadavenkatesan, Thivaharan; Vinayagam, Ramesh

    2017-01-01

    In the present investigation, the leaf extract of Cynometra ramiflora was used to synthesize iron oxide nanoparticles. Within minutes of adding iron sulphate to the leaf extract, iron oxide nanoparticles were formed and thus, the method is very simple and fast. UV-VIS spectra showed the strong absorption band in the visible region. SEM images showed discrete spherical shaped particles and EDS spectra confirmed the iron and oxygen presence. The XRD results depicted the crystalline structure of iron oxide nanoparticles. FT-IR spectra portrayed the existence of functional groups of phytochemicals which are probably involved in the formation and stabilization of nanoparticles. The iron oxide nanoparticles exhibited effective inhibition against E. coli and S. epidermidis which may find its applications in the antibacterial drug development. Furthermore, the catalytic activity of the nanoparticles as Fenton-like catalyst was successfully investigated for the degradation of Rhodamine-B dye. This outcome could play a prominent role in the wastewater treatment.

  2. An Efficient and Facile Methodology for Bromination of Pyrimidine and Purine Nucleosides with Sodium Monobromoisocyanurate (SMBI

    Directory of Open Access Journals (Sweden)

    Roger Stromberg

    2013-10-01

    Full Text Available An efficient and facile strategy has been developed for bromination of nucleosides using sodium monobromoisocyanurate (SMBI. Our methodology demonstrates bromination at the C-5 position of pyrimidine nucleosides and the C-8 position of purine nucleosides. Unprotected and also several protected nucleosides were brominated in moderate to high yields following this procedure.

  3. A Rapid Screening Assay Identifies Monotherapy with Interferon-ß and Combination Therapies with Nucleoside Analogs as Effective Inhibitors of Ebola Virus.

    Directory of Open Access Journals (Sweden)

    Stephen D S McCarthy

    2016-01-01

    Full Text Available To date there are no approved antiviral drugs for the treatment of Ebola virus disease (EVD. While a number of candidate drugs have shown limited efficacy in vitro and/or in non-human primate studies, differences in experimental methodologies make it difficult to compare their therapeutic effectiveness. Using an in vitro model of Ebola Zaire replication with transcription-competent virus like particles (trVLPs, requiring only level 2 biosafety containment, we compared the activities of the type I interferons (IFNs IFN-α and IFN-ß, a panel of viral polymerase inhibitors (lamivudine (3TC, zidovudine (AZT tenofovir (TFV, favipiravir (FPV, the active metabolite of brincidofovir, cidofovir (CDF, and the estrogen receptor modulator, toremifene (TOR, in inhibiting viral replication in dose-response and time course studies. We also tested 28 two- and 56 three-drug combinations against Ebola replication. IFN-α and IFN-ß inhibited viral replication 24 hours post-infection (IC50 0.038μM and 0.016μM, respectively. 3TC, AZT and TFV inhibited Ebola replication when used alone (50-62% or in combination (87%. They exhibited lower IC50 (0.98-6.2μM compared with FPV (36.8μM, when administered 24 hours post-infection. Unexpectedly, CDF had a narrow therapeutic window (6.25-25μM. When dosed >50μM, CDF treatment enhanced viral infection. IFN-ß exhibited strong synergy with 3TC (97.3% inhibition or in triple combination with 3TC and AZT (95.8% inhibition. This study demonstrates that IFNs and viral polymerase inhibitors may have utility in EVD. We identified several 2 and 3 drug combinations with strong anti-Ebola activity, confirmed in studies using fully infectious ZEBOV, providing a rationale for testing combination therapies in animal models of lethal Ebola challenge. These studies open up new possibilities for novel therapeutic options, in particular combination therapies, which could prevent and treat Ebola infection and potentially reduce drug

  4. A novel nucleoside kinase from Burkholderia thailandensis: a member of the phosphofructokinase B-type family of enzymes.

    Science.gov (United States)

    Ota, Hiroko; Sakasegawa, Shin-Ichi; Yasuda, Yuko; Imamura, Shigeyuki; Tamura, Tomohiro

    2008-12-01

    The genome of the mesophilic Gram-negative bacterium Burkholderia thailandensis contains an open reading frame (i.e. the Bth_I1158 gene) that has been annotated as a putative ribokinase and PFK-B family member. Notably, although the deduced amino acid sequence of the gene showed only 29% similarity to the recently identified nucleoside kinase from hyperthermophilic archaea Methanocaldococcus jannaschii, 15 of 17 residues reportedly involved in the catalytic activity of M. jannaschii nucleoside kinase were conserved. The gene was cloned and functionally overexpressed in Rhodococcus erythropolis, and the purified enzyme was characterized biochemically. The substrate specificity of the enzyme was unusually broad for a bacterial PFK-B protein, and the specificity extended not only to purine and purine-analog nucleosides but also to uridine. Inosine was the most effective phosphoryl acceptor, with the highest k(cat)/K(m) value (80 s(-1).mm(-1)) being achieved when ATP served as the phosphoryl donor. By contrast, this enzyme exhibited no activity toward ribose, indicating that the recombinant enzyme was a nucleoside kinase rather than a ribokinase. To our knowledge, this is the first detailed analysis of a bacterial nucleoside kinase in the PFK-B family.

  5. Attribution of antibacterial and antioxidant activity of Cassia tora extract toward its growth promoting effect in broiler birds

    Science.gov (United States)

    Sahu, Jyoti; Koley, K. M.; Sahu, B. D.

    2017-01-01

    Aim: The study was conducted to evaluate the attribution of antibacterial and antioxidant activity of methanolic extract of Cassia tora toward its growth promoting effect in broiler birds. Materials and Methods: A limit test was conducted for C. tora extract in Wistar albino rats. Phytochemical screening of methanolic extract of leaves of C. tora was carried out. In-vitro antibacterial activity was measured by disc diffusion method. 1-day-old Ven Cobb broiler birds (n=90) were randomly allocated into three groups consisting of three replicates with 10 birds in each group. The birds of group T1 (Control) received basal diet, whereas birds of group T2 (Standard) received an antibiotic (Lincomycin at 0.05% in feed). The birds of group T3 (Test) received Cassia tora extract (CSE) at 0.4 g/L in drinking water in addition to basal diet. The treatment was given to birds of all the groups for 6 weeks. Antioxidant activity of C. tora was determined in blood of broiler birds. Cumulative body weight gain, feed intake, feed conversion ratio (FCR), dressing percent, and organ weight factor were evaluated to determine growth performance in broiler birds. Results: Phytochemicals in C. tora were screened. Sensitivity to Escherichia coli and resistant to Staphylococcus aureus and Pseudomonas aeruginosa was observed in in-vitro antibacterial activity test. At the end of 6th week, antioxidant activity reflected significantly (p≤0.05) lower level of erythrocyte malondialdehyde and higher levels of reduced glutathione (GSH) and GSH peroxidase in broiler birds of group T2 and T3 as compared to broiler of group T1. Mean cumulative body weight gain of birds of T2 and T3 were significantly (p≤0.05) higher as compared to T1. Mean FCR of birds of group T3 decreased significantly than group T1. Conclusion: Supplementation of C. tora leaves extract at 0.4 g/L in drinking water improved growth performance in broiler birds due to its antimicrobial and antioxidant activity. Therefore, it

  6. Surveying the Effect of the Phenol Compounds on Antibacterial Activity of Herbal Extracts: In vitro Assessment of Herbal Extracts in Fasa-Fars Province

    Directory of Open Access Journals (Sweden)

    Elahe Ahmadi

    2016-09-01

    Full Text Available Background & Objectives: Due to increase in  bacterial drug resistance, discovering new antibacterial compounds is really important. The objective of this study is to evaluate the phenol compounds effect on antibacterial activity of herbal extracts of Fasa-Fars province in vitro. Materials & Methods: The antibacterial activity of 26 plants was studied by disk diffusion, well, and MIC methods in compare with 13 standard antibiotics against S. aureus and E. coli as control bacteria. Measurement of phenol compounds were performed by Seevers and Daly colorimetric methods using Folin-ciocalteu indicator. Results: Inhibition zone of bacterial growth  against S. aureus in well and disk methods were 32 and 22 mm in using Zataria multiflora, respectively .And there were 23 and 16 mm against E. coli in Zataria multiflora, respectively. Less effects and inhibition zones, less than 15mm on both strains, were seen in using  Saturina hortensis, Cinamomum zeylanicum, ­Artemisia absinthium, ­Urtica dioica, Carum carvi L. cyminum Cuminum, Achillea fragrantissimia, Marticaria chamomilla, Zingiber officinale, Origanum majorana, and Plantago psyllium. Most effective MIC results, 7.8 µg/ml, were related to the extracts of Zataria multiflora, Carum copticum L. Rosmarinus officinalis L., and Laurus nobilis L. Phenol compound amounts were approximately between 66.51±1.9 and 233.15±5.1 mg/gr extract in Zataria multiflora and Plantago psyllium, respectively. Conclusion: Results of antibacterial activity of extracts and relation with phenol compound amounts indicate the antibacterial effect of phenol compounds in herbal extracts.

  7. Dynamic metabolic labeling of DNA in vivo with arabinosyl nucleosides.

    Science.gov (United States)

    Neef, Anne B; Luedtke, Nathan W

    2011-12-20

    Commonly used metabolic labels for DNA, including 5-ethynyl-2'-deoxyuridine (EdU) and BrdU, are toxic antimetabolites that cause DNA instability, necrosis, and cell-cycle arrest. In addition to perturbing biological function, these properties can prevent metabolic labeling studies where subsequent tissue survival is needed. To bypass the metabolic pathways responsible for toxicity, while maintaining the ability to be metabolically incorporated into DNA, we synthesized and evaluated a small family of arabinofuranosyl-ethynyluracil derivatives. Among these, (2'S)-2'-deoxy-2'-fluoro-5-ethynyluridine (F-ara-EdU) exhibited selective DNA labeling, yet had a minimal impact on genome function in diverse tissue types. Metabolic incorporation of F-ara-EdU into DNA was readily detectable using copper(I)-catalyzed azide-alkyne "click" reactions with fluorescent azides. F-ara-EdU is less toxic than both BrdU and EdU, and it can be detected with greater sensitivity in experiments where long-term cell survival and/or deep-tissue imaging are desired. In contrast to previously reported 2'-arabino modified nucleosides and EdU, F-ara-EdU causes little or no cellular arrest or DNA synthesis inhibition. F-ara-EdU is therefore ideally suited for pulse-chase experiments aimed at "birth dating" DNA in vivo. As a demonstration, Zebrafish embryos were microinjected with F-ara-EdU at the one-cell stage and chased by BrdU at 10 h after fertilization. Following 3 d of development, complex patterns of quiescent/senescent cells containing only F-ara-EdU were observed in larvae along the dorsal side of the notochord and epithelia. Arabinosyl nucleoside derivatives therefore provide unique and effective means to introduce bioorthogonal functional groups into DNA for diverse applications in basic research, biotechnology, and drug discovery.

  8. 106 ASSESSMENT OF ANTI-BACTERIAL EFFECTS OF PEGYLATED SILVER-COATED CARBON NANOTUBES ON CAUSATIVE BACTERIA OF BOVINE INFERTILITY USING BIOLUMINESCENCE IMAGING SYSTEM.

    Science.gov (United States)

    Park, S; Chaudhari, A A; Pillai, S; Singh, S R; Willard, S T; Ryan, P L; Feugang, J M

    2016-01-01

    Pathogenic bacteria including Escherichia coli and Salmonella sp. are the major causative agents of endometritis and can cause infertility in livestock animals. Antibiotics are commonly used to terminate bacterial infections, but the development of bacterial antibiotic resistance is often encountered. Nanotechnology associated with silver nanoparticles has been highlighted as an alternative anti-bacterial agent, and pegylated silver-coated single-walled carbon nanotubes have high anti-bacterial effects and are non-toxic to human and murine cells in vitro. Here we verified whether a real-time bioluminescence monitoring system could be an alternative tool to assess anti-bacterial effects of nanotubes in a noninvasive approach. Escherichia coli and Salmonella sp. were transfected with plasmids containing constructs for luciferase enzyme (LuxCDABE) and substrate (luciferin) to create self-illuminating bioluminescent bacteria. Pathogens were grown in LB broth at 37°C, adjusted to 10(7) cfumL(-1), and placed in 96-well plates for treatments. Pegylated (pSWCNTs-Ag) and non-pegylated (SWCNTs-Ag) nanotubes were prepared and added to culture wells at various concentrations (31.25-125µgmL(-1)). The control group corresponded to bacteria without nanotubes (0µgmL(-1)). Anti-bacterial effects of nanotubes were determined every 10min until 1h, then every 30min up to 6h incubation through optical density (600nm) measurements and bioluminescence imaging (BLI) and quantification using an IVIS system. Optical density and BLI data were compared at each time-point using 2-way ANOVA, with PBioluminescence signals emitted by both bacteria stains appeared within 10min of incubation. Thereafter, control bacteria showed exponential growth that was detected as early as 25min post-incubation. Bioluminescence imaging revealed dose-dependent anti-bacterial activities of both pSWCNTs-Ag and SWCNTs-Ag on each E. coli and Salmonella sp. (P0.05); meanwhile, pSWCNTs-Ag nanotubes exhibited

  9. What makes a natural clay antibacterial?

    Science.gov (United States)

    Williams, Lynda B.; Metge, David W.; Eberl, Dennis D.; Harvey, Ronald W.; Turner, Amanda G.; Prapaipong, Panjai; Port-Peterson, Amisha T.

    2011-01-01

    Natural clays have been used in ancient and modern medicine, but the mechanism(s) that make certain clays lethal against bacterial pathogens has not been identified. We have compared the depositional environments, mineralogies, and chemistries of clays that exhibit antibacterial effects on a broad spectrum of human pathogens including antibiotic resistant strains. Natural antibacterial clays contain nanoscale (2+ solubility.

  10. Effects of nucleotides and nucleosides on coagulation

    DEFF Research Database (Denmark)

    Bune, Laurids; Thaning, Pia; Johansson, Pär I;

    2010-01-01

    Nucleotides, including ADP, ATP and uridine triphosphate (UTP), are discharged profusely in the circulation during many pathological conditions including sepsis. Sepsis can cause hypotension and systemic activation of the coagulation and fibrinolytic systems in humans, which may cause disseminated...... intravascular coagulation. We investigated whether nucleotide-induced cardiovascular collapse as provoked by systemic infusion of adenosine, ADP, ATP, UTP and nitric oxide affected the haemostatic system as assessed by whole blood thromboelastography (TEG) analysis. Ten pigs received a randomized infusion...

  11. Effects of nucleotides and nucleosides on coagulation

    DEFF Research Database (Denmark)

    Bune, Laurids; Thaning, Pia; Johansson, Pär I;

    2010-01-01

    intravascular coagulation. We investigated whether nucleotide-induced cardiovascular collapse as provoked by systemic infusion of adenosine, ADP, ATP, UTP and nitric oxide affected the haemostatic system as assessed by whole blood thromboelastography (TEG) analysis. Ten pigs received a randomized infusion......Nucleotides, including ADP, ATP and uridine triphosphate (UTP), are discharged profusely in the circulation during many pathological conditions including sepsis. Sepsis can cause hypotension and systemic activation of the coagulation and fibrinolytic systems in humans, which may cause disseminated.......7 ng/ml; P blood was evaluated by TEG. Circulating ADP induces hypocoagulation without signs of increased fibrinolysis as evaluated by TEG. The potential...

  12. Experimental studies on antipyretic, analgesic and antibacterial effects of GK 001, a poly-prescription of traditional chinese medicine

    Institute of Scientific and Technical Information of China (English)

    JIANG Su-yun; ZhANG Ting-ting; DING Hong-yu

    2008-01-01

    Objective To study the anti-inflammatory effect of a poly-prescription of traditional Chinese medicine GK001. Methods 1. Inhibitory effect on pain in mice: The pain was induced by i. p. 0.2 ml of 0.6 % HAc per mouse 1 h post dosing GK001. The writhing numbers of mice were recorded in 10 minutes and the inhibitory rate of pain was calculated compared with the control group. 2. Antipyretie effect In single dose experiment 15 healthy rabbits weighing 1.7-2.8 kg with body temperature(BT) measured in the experiment day meeting to the requirements were selected for the experiment and divided into 5 groups(3 in each group), which were dosed orally with GK001 and 1 h later followed by i. p. injection of 40 EU bacterial endotoxin standard·kg-1. Then, the BT of rabbits was measured every 30 min during 1-3 h after administration. The difference between the highest BT post-dose and the average BT pre-dose was calculated. In multi-dose experiment rabbits were selected and grouped as well as received i. p. endotoxin in the same way as above, but were administered with GK001 for consecutive 5 day. 3. Bacteriostatie effect. The antibacterial activities of GK001 on Bacillus Pumilus, Bacillus Subtilis and Micrococcus Luteus were measured in vitro at concentrations of 0.125-1.0 g·mL-1. Results 1. The GK001 showed a significant and dose-dependent painsuppressant effect, with inhibitory rate being 45.2 %, 31.2 % and 20.8 % at high, medium and low dose, respectively (P< 0.05). 2. Both single and multiple administration of GK001 had no effect on rabbit pyrogen response caused by endotoxin. 3. GK001 had bacteriostatic effects on the aforementioned 3 bacteria significantly and in dose-dependent fashion. Conclusions GK001 has analgesic and in vitro antibacterial but no antipyretie effects.

  13. Analysis on Anti-bacterial Effect of Three Antibiotics by Bioassay%微生物法对三种抗生素抗菌作用的分析

    Institute of Scientific and Technical Information of China (English)

    顾勤芬; 虞盘兴; 武煜; 管明敏

    2003-01-01

    Objective To boserve the antibacterial effect of several commonly used oral antibiotics clinically, chooseproper drugs according to the sympotms and take the price into consideration. Methods To analyze the antibacterial effect inclinical of Ampicillin, Cephradine and Cifram on commomly seen pathogens, including G+ and G- bacteria. Results Thereis some difference between three antibiotics in the effect on bacteria. Cifram has stronger antibacterial effect compared withAmpicillin and Cepgradine on Enterobacter cloacae, Klebsiella pneumoniae and Enterococcus faecalils. The effect ofAmpicillin on Staph. Aureus is far superior to Cifran and cephradine. Cephradine is ineffective to Enterobacter cloacae andPseudomonos aeruginosa. Only Cifran has antibacterial effect on Pseudomonos aeruginosa. Conclusion To select and usedrugs reasonably and clinically. to indective diseases, such factors sa variety of pathogens, the sensitivity of antibiotic,potency, the price of drug should be considered comprehensively. Not all expensive drugs have satisfied therapeutic effect.

  14. The effects of Mg incorporation and annealing temperature on the physicochemical properties and antibacterial activity against Listeria monocytogenes of ZnO nanoparticles

    Science.gov (United States)

    Shadan, Nima; Ziabari, Ali Abdolahzadeh; Meraat, Rafieh; Jalali, Kamyar Mazloum

    2017-02-01

    In this paper, Mg-doped ZnO nanoparticles were synthesized by the facile sol-gel method. The crystalline structure, characteristic absorption bands and morphology of the obtained Mg-doped ZnO nanoparticles were studied by XRD, FTIR and TEM. The thermal degradation behaviour of the samples was investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG). The effect of Mg concentrations and annealing temperatures on the antibacterial properties of the obtained nanoparticles was investigated in detail. The results indicated that doping Mg ions into ZnO lattice could enhance its antibacterial activity. Antibacterial assay demonstrated that Mg-doped ZnO with 7% Mg content annealed at 400 ∘C had the strongest antibacterial activity against Listeria monocytogenes (98.7%). This study indicated that the inhibition rate of ZnO nanoparticles increased with the formation of granular structure and the decrease of ZnO size due to the doping of Mg ions into the ZnO lattice.

  15. Biopolymers Regulate Silver Nanoparticle under Microwave Irradiation for Effective Antibacterial and Antibiofilm Activities.

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    Palaniyandi Velusamy

    Full Text Available In the current study, facile synthesis of carboxymethyl cellulose (CMC and sodium alginate capped silver nanoparticles (AgNPs was examined using microwave radiation and aniline as a reducing agent. The biopolymer matrix embedded nanoparticles were synthesized under various experimental conditions using different concentrations of biopolymer (0.5, 1, 1.5, 2%, volumes of reducing agent (50, 100, 150 μL, and duration of heat treatment (30 s to 240 s. The synthesized nanoparticles were analyzed by scanning electron microscopy, UV-Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy for identification of AgNPs synthesis, crystal nature, shape, size, and type of capping action. In addition, the significant antibacterial efficacy and antibiofilm activity of biopolymer capped AgNPs were demonstrated against different bacterial strains, Staphylococcus aureus MTCC 740 and Escherichia coli MTCC 9492. These results confirmed the potential for production of biopolymer capped AgNPs grown under microwave irradiation, which can be used for industrial and biomedical applications.

  16. Biopolymers Regulate Silver Nanoparticle under Microwave Irradiation for Effective Antibacterial and Antibiofilm Activities.

    Science.gov (United States)

    Velusamy, Palaniyandi; Su, Chia-Hung; Venkat Kumar, Govindarajan; Adhikary, Shritama; Pandian, Kannaiyan; Gopinath, Subash C B; Chen, Yeng; Anbu, Periasamy

    2016-01-01

    In the current study, facile synthesis of carboxymethyl cellulose (CMC) and sodium alginate capped silver nanoparticles (AgNPs) was examined using microwave radiation and aniline as a reducing agent. The biopolymer matrix embedded nanoparticles were synthesized under various experimental conditions using different concentrations of biopolymer (0.5, 1, 1.5, 2%), volumes of reducing agent (50, 100, 150 μL), and duration of heat treatment (30 s to 240 s). The synthesized nanoparticles were analyzed by scanning electron microscopy, UV-Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy for identification of AgNPs synthesis, crystal nature, shape, size, and type of capping action. In addition, the significant antibacterial efficacy and antibiofilm activity of biopolymer capped AgNPs were demonstrated against different bacterial strains, Staphylococcus aureus MTCC 740 and Escherichia coli MTCC 9492. These results confirmed the potential for production of biopolymer capped AgNPs grown under microwave irradiation, which can be used for industrial and biomedical applications.

  17. Ligand effects on the structural dimensionality and antibacterial activities of silver-based coordination polymers.

    Science.gov (United States)

    Lu, Xinyi; Ye, Junwei; Sun, Yuan; Bogale, Raji Feyisa; Zhao, Limei; Tian, Peng; Ning, Guiling

    2014-07-14

    Four Ag-based coordination polymers [Ag(Bim)] (1), [Ag2(NIPH)(HBim)] (2), [Ag6(4-NPTA)(Bim)4] (3) and [Ag2(3-NPTA)(bipy)0.5(H2O)] (4) (HBim = 1H-benzimidazole, bipy = 4,4'-bipyridyl, H2NIPH = 5-nitroisophthalic acid, H2NPTA = 3-/4-nitrophthalic acid) have been synthesized by hydrothermal reaction of Ag(i) salts with N-/O-donor ligands. Single-crystal X-ray diffraction indicated that these coordination polymers constructed from mononuclear or polynuclear silver building blocks exhibit three typical structure features from 1-D to 3-D frameworks. These compounds favour a slow release of Ag(+) ions leading to excellent and long-term antimicrobial activities, which is distinguished by their different topological structures, towards both Gram-negative bacteria, Escherichia coli (E. coli) and Gram-positive bacteria, Staphylococcus aureus (S. aureus). In addition, these compounds show good thermal stability and light stability under UV-vis and visible light, which are important characteristics for their further application in antibacterial agents.

  18. Ligational behavior of Schiff bases towards transition metal ion and metalation effect on their antibacterial activity

    Science.gov (United States)

    Devi, Jai; Batra, Nisha; Malhotra, Rajesh

    2012-11-01

    New Schiff bases pyrazine-2-carboxylicacid (phenyl-pyridin-2-yl-methylene)-hydrazide (Hpch-bp) HL1 and pyrazine-2-carboxylicacid (pyridin-2-ylmethylene)-hydrazide (Hpch-pc) HL2 derived from condensation of pyrazine carboxylic hydrazide (Hpch) with 2-benzoyl pyridine (bp) or pyridine 2-carbaldehyde (pc) and their transition metal complexes of type ML(1-2)2 have been synthesized, where M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). Characterization of ligands and their metal complexes was carried out by elemental analysis, conductimetric studies, magnetic susceptibility, spectroscopic techniques (IR, UV-VIS, NMR, ESR, Mass) and thermogravimetric analysis. The physico-chemical studies revealed octahedral geometry or distorted octahedral geometry around metal ion. These azomethine Schiff base ligands acted as tridentate ? coordinating through carbonyl, azomethine and pyridine nitrogen present in the ligand. The thermodynamic and thermal properties of the complexes have been investigated and it was observed on the basis of these studies that thermal stability of complexes follows the order Mn complexes were tested for in vitro antibacterial activity at different concentrations against bacteria viz. Gram positive Bacillus subtilis, Micrococcus luteus and Gram negative Pseudomonas aeruginosa, Pseudomonas mendocina. A marked enhancement in biocidal activity of the ligands under similar experimental conditions was observed as a consequence of coordination with metal ions. The trend of growth inhibition in the complexes was found to be in the order: Cu > Mn > Ni > Co > Zn.

  19. Current prodrug strategies for improving oral absorption of nucleoside analogues

    Directory of Open Access Journals (Sweden)

    Youxi Zhang

    2014-04-01

    Full Text Available Nucleoside analogues are first line chemotherapy in various severe diseases: AIDS (acquired immunodeficiency disease syndrome, cytomegalovirus infections, cancer, etc. However, many nucleoside analogues exhibit poor oral bioavailability because of their high polarity and low intestinal permeability. In order to get around this drawback, prodrugs have been utilized to improve lipophilicity by chemical modification of the parent drug. Alternatively, prodrugs targeting transporters present in the intestine have been applied to promote the transport of the nucleoside analogues. Valacyclovir and valganciclovir are two classic valine ester prodrugs transported by oligopeptide transporter 1. The ideal prodrug achieves delivery of a parent drug by attaching a non-toxic moiety that is stable during transport, but is readily degraded to the parent drug once at the target. This article presents advances of prodrug approaches for enhancing oral absorption of nucleoside analogues.

  20. A Modular Approach to Phosphoglycosyltransferase Inhibitors Inspired by Nucleoside Antibiotics

    NARCIS (Netherlands)

    Walvoort, Marthe T C; Lukose, Vinita; Imperiali, Barbara

    2015-01-01

    Phosphoglycosyltransferases (PGTs) represent "gatekeeper" enzymes in complex glycan assembly pathways by catalyzing transfer of a phosphosugar from an activated nucleotide diphosphosugar to a membrane-resident polyprenol phosphate. The unique structures of selected nucleoside antibiotics, such as tu

  1. Palladium-Catalyzed Modification of Unprotected Nucleosides, Nucleotides, and Oligonucleotides

    Directory of Open Access Journals (Sweden)

    Kevin H. Shaughnessy

    2015-05-01

    Full Text Available Synthetic modification of nucleoside structures provides access to molecules of interest as pharmaceuticals, biochemical probes, and models to study diseases. Covalent modification of the purine and pyrimidine bases is an important strategy for the synthesis of these adducts. Palladium-catalyzed cross-coupling is a powerful method to attach groups to the base heterocycles through the formation of new carbon-carbon and carbon-heteroatom bonds. In this review, approaches to palladium-catalyzed modification of unprotected nucleosides, nucleotides, and oligonucleotides are reviewed. Polar reaction media, such as water or polar aprotic solvents, allow reactions to be performed directly on the hydrophilic nucleosides and nucleotides without the need to use protecting groups. Homogeneous aqueous-phase coupling reactions catalyzed by palladium complexes of water-soluble ligands provide a general approach to the synthesis of modified nucleosides, nucleotides, and oligonucleotides.

  2. Crystal structure of a concentrative nucleoside transporter from Vibrio cholerae at 2.4;#8201;Å

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Zachary Lee; Cheong, Cheom-Gil; Lee, Seok-Yong (Duke)

    2012-07-11

    Nucleosides are required for DNA and RNA synthesis, and the nucleoside adenosine has a function in a variety of signalling processes. Transport of nucleosides across cell membranes provides the major source of nucleosides in many cell types and is also responsible for the termination of adenosine signalling. As a result of their hydrophilic nature, nucleosides require a specialized class of integral membrane proteins, known as nucleoside transporters (NTs), for specific transport across cell membranes. In addition to nucleosides, NTs are important determinants for the transport of nucleoside-derived drugs across cell membranes. A wide range of nucleoside-derived drugs, including anticancer drugs (such as Ara-C and gemcitabine) and antiviral drugs (such as zidovudine and ribavirin), have been shown to depend, at least in part, on NTs for transport across cell membranes. Concentrative nucleoside transporters, members of the solute carrier transporter superfamily SLC28, use an ion gradient in the active transport of both nucleosides and nucleoside-derived drugs against their chemical gradients. The structural basis for selective ion-coupled nucleoside transport by concentrative nucleoside transporters is unknown. Here we present the crystal structure of a concentrative nucleoside transporter from Vibrio cholerae in complex with uridine at 2.4 {angstrom}. Our functional data show that, like its human orthologues, the transporter uses a sodium-ion gradient for nucleoside transport. The structure reveals the overall architecture of this class of transporter, unravels the molecular determinants for nucleoside and sodium binding, and provides a framework for understanding the mechanism of nucleoside and nucleoside drug transport across cell membranes.

  3. Substituted Hydroxyapatites with Antibacterial Properties

    Directory of Open Access Journals (Sweden)

    Joanna Kolmas

    2014-01-01

    Full Text Available Reconstructive surgery is presently struggling with the problem of infections located within implantation biomaterials. Of course, the best antibacterial protection is antibiotic therapy. However, oral antibiotic therapy is sometimes ineffective, while administering an antibiotic at the location of infection is often associated with an unfavourable ratio of dosage efficiency and toxic effect. Thus, the present study aims to find a new factor which may improve antibacterial activity while also presenting low toxicity to the human cells. Such factors are usually implemented along with the implant itself and may be an integral part of it. Many recent studies have focused on inorganic factors, such as metal nanoparticles, salts, and metal oxides. The advantages of inorganic factors include the ease with which they can be combined with ceramic and polymeric biomaterials. The following review focuses on hydroxyapatites substituted with ions with antibacterial properties. It considers materials that have already been applied in regenerative medicine (e.g., hydroxyapatites with silver ions and those that are only at the preliminary stage of research and which could potentially be used in implantology or dentistry. We present methods for the synthesis of modified apatites and the antibacterial mechanisms of various ions as well as their antibacterial efficiency.

  4. Substituted hydroxyapatites with antibacterial properties.

    Science.gov (United States)

    Kolmas, Joanna; Groszyk, Ewa; Kwiatkowska-Różycka, Dagmara

    2014-01-01

    Reconstructive surgery is presently struggling with the problem of infections located within implantation biomaterials. Of course, the best antibacterial protection is antibiotic therapy. However, oral antibiotic therapy is sometimes ineffective, while administering an antibiotic at the location of infection is often associated with an unfavourable ratio of dosage efficiency and toxic effect. Thus, the present study aims to find a new factor which may improve antibacterial activity while also presenting low toxicity to the human cells. Such factors are usually implemented along with the implant itself and may be an integral part of it. Many recent studies have focused on inorganic factors, such as metal nanoparticles, salts, and metal oxides. The advantages of inorganic factors include the ease with which they can be combined with ceramic and polymeric biomaterials. The following review focuses on hydroxyapatites substituted with ions with antibacterial properties. It considers materials that have already been applied in regenerative medicine (e.g., hydroxyapatites with silver ions) and those that are only at the preliminary stage of research and which could potentially be used in implantology or dentistry. We present methods for the synthesis of modified apatites and the antibacterial mechanisms of various ions as well as their antibacterial efficiency.

  5. Distribution of nucleosides in populations of Cordyceps cicadae.

    Science.gov (United States)

    Zeng, Wen-Bo; Yu, Hong; Ge, Feng; Yang, Jun-Yuan; Chen, Zi-Hong; Wang, Yuan-Bing; Dai, Yong-Dong; Adams, Alison

    2014-05-14

    A rapid HPLC method had been developed and used for the simultaneous determination of 10 nucleosides (uracil, uridine, 2'-deoxyuridine, inosine, guanosine, thymidine, adenine, adenosine, 2'-deoxyadenosine and cordycepin) in 10 populations of Cordyceps cicadae, in order to compare four populations of Ophicordyceps sinensis and one population of Cordyceps militaris. Statistical analysis system (SAS) 8.1 was used to analyze the nucleoside data. The pattern of nucleoside distribution was analyzed in the sampled populations of C. cicadae, O. sinensis and C. militaris, using descriptive statistical analysis, nested analysis and Q cluster analysis. The total amount of the 10 nucleosides in coremium was 1,463.89-5,678.21 µg/g in 10 populations of C. cicadae, 1,369.80-3,941.64 µg/g in sclerotium. The average contents of the 10 analytes were 4,392.37 µg/g and 3,016.06 µg/g in coremium and sclerotium, respectively. The coefficient of variation (CV) of nucleosides ranged from 8.36% to 112.36% in coremium of C. cicadae, and from 10.77% to 155.87% in sclerotium of C. cicadae. The CV of the nucleosides was wide within C. cicadae populations. The nested variation analysis by the nine nucleosides' distribution indicated that about 42.29% of the nucleoside variability in coremium was attributable to the differentiation among populations, and the remaining 57.71% resided in the populations. It was also shown that about 28.94% of the variation in sclerotium was expressed between populations, while most of the variation (71.06%) corresponded to the populations.

  6. Evaluation of combined antibacterial effects of eugenol, cinnamaldehyde, thymol, and carvacrol against E. coli with an improved method.

    Science.gov (United States)

    Pei, Rui-Song; Zhou, Feng; Ji, Bao-Ping; Xu, Jing

    2009-09-01

    In this study, the antibacterial activities of eugenol, cinnamaldehyde, thymol, carvacrol, and their combinations against E. coli were investigated separately. First, broth macro-dilution assay was adopted to determine the minimal inhibitory concentration (MIC) of the 4 components. Second, the combination testing was performed using chequerboard method. Finally, the combined effects were evaluated with an improved method, which was based on the indices of fractional inhibitory concentration (FIC) and Effect of the Combination (EC) jointly. The results indicated that MICs of the 4 components were 1600, 400, 400, and 400 mg/L, respectively; treatments with cinnamaldehyde/eugenol, thymol/eugenol, carvacrol/eugenol, and thymol/carvacrol revealed synergistic effects according to the 2 indices. By means of combination, MICs of eugenol, cinnamaldehyde, thymol, and carvacrol decreased to 400, 100, 100, and 100 mg/L, respectively. Consequently, the negative impacts of unpleasant smell of these 4 components could be minimized, making it possible to add them to foods as preservatives. In addition, this improved evaluation method provided a more accurate and comprehensive way to evaluate combined effects.

  7. Antioxidant/Prooxidant and Antibacterial/Probacterial Effects of a Grape Seed Extract in Complex with Lipoxygenase

    Directory of Open Access Journals (Sweden)

    Veronica Sanda Chedea

    2014-01-01

    Full Text Available In an attempt to determine the antioxidant/prooxidant, antibacterial/probacterial action of flavan-3-ols and procyanidins from grape seeds, pure catechin (CS, and an aqueous grape seed extract (PE, were applied in the absence and presence of pure lipoxygenase (LS or in extract (LE to leucocyte culture, Escherichia coli B41 and Brevibacterium linens, and observed whether there was any effect on lipid peroxidation, cytotoxicity, or growth rate. Short time periods of coincubation of cells with the polyphenols, followed by the exposure to LS and LE, revealed a high level of lipid peroxidation and a prooxidative effect. Longer coincubation and addition of LS and LE resulted in the reversal of the prooxidant action either to antioxidant activity for CS + LS and PE + LS or to the control level for CS + LE and PE + LE. Lipid peroxidation was significantly reduced when cells were exposed to polyphenols over a longer period. Longer exposure of E. coli to CS or PE followed by addition of LS for 3 h resulted in bactericidal activity. Significant stimulatory effect on microbial growth was observed for PE + LS and PE + LE treatments in B. linens, illustrating the potential probacterial activity in B. linens cultures. Lipoxygenase-polyphenols complex formation was found to be responsible for the observed effects.

  8. Survey of Anti-Bacterial Effect of Plant Extracts (Fennel-Dill-Caraway-Cinnamon by Flow Cytometry and Disk Diffusion

    Directory of Open Access Journals (Sweden)

    P. Ranjbarian

    2004-10-01

    Full Text Available H.pylori has been discovered as an etiologic agent for peptic ulcer and gastric cancer. It is well known that eradicating H.pylori is an essential step in curing ulcer disease. Many regimens are currently available but none of them can achieve 100% eradication rate . In this research, anti-bacterial effect of extracts of:fennel, dill, caraway, cinnamon and antibiotics of: ciprofloxacin, Tetracyclin and amoxycillin were investigated against H.pylori by disk diffusion method and flow cytometry. In this study we used culture and rapid urease Test , catalase, oxidase and also staining to recognize H.pylori in 30 biopsies that has been taken from patients . 14 cases (46.66% were positive for H.pylori infection. Disk diffusion method was used to detremine the sensitivity of H.pylori to some selective antibiotics and plant extracts. In analysis of information it has been used from nonparametric Cochran test and for comparisons between plant extracts of different groups, the Mcnemar and Bonferroni tests was used. In this study, bacterial viability was surveyed after being subjected to plant extracts and antibiotics by flow cytometry . Results showed that all of the bacteria were susceptible to plant extracts and the highest sensitivity was obtained with dill. All bacteria were susceptible to ciprofloxacin , tetracyclin and were resistant to amoxicillin. Flow cytometry showed that ciprofloxacin had bacteriocidal effect, tetra cyclin had bacteriostatic effect and could not kill bacteria whereas plant extracts had bacteriostatic effect .

  9. Synthesis of coumarin or ferrocene labeled nucleosides via Staudinger ligation

    Directory of Open Access Journals (Sweden)

    Kois Pavol

    2006-11-01

    Full Text Available Abstract Background Reaction of azides with triaryl phosphines under mild conditions gives iminophosphoranes which can react with almost any kind of electrophilic reagent, e.g. aldehydes/ketones to form imines or esters to form amides. This so-called Staudinger ligation has been employed in a wide range of applications as a general tool for bioconjugation including specific labeling of nucleic acids. Results A new approach for the preparation of labeled nucleosides via intermolecular Staudinger ligation is described. Reaction of azidonucleosides with triphenylphosphine lead to iminophosphorane intermediates, which react subsequently with derivatives of coumarin or ferrocene to form coumarin or ferrocene labeled nucleosides. Fluorescent properties of coumarin labeled nucleosides are determined. Conclusion New coumarin and ferrocene labeled nucleosides were prepared via intermolecular Staudinger ligation. This reaction joins the fluorescent coumarin and biospecific nucleoside to the new molecule with promising fluorescent and electrochemical properties. The isolated yields of products depend on the structure of azidonucleoside and carboxylic acids. A detailed study of the kinetics of the Staudinger ligation with nucleoside substrates is in progress.

  10. Antimalarial action of nitrobenzylthioinosine in combination with purine nucleoside antimetabolites.

    Science.gov (United States)

    Gero, A M; Scott, H V; O'Sullivan, W J; Christopherson, R I

    1989-04-01

    The infection of human erythrocytes by two strains of the human malarial parasite, Plasmodium falciparum (FCQ-27 or the multi-drug-resistant strain K-1), markedly changed the transport characteristics of the nucleosides, adenosine and tubercidin, compared to uninfected erythrocytes. A component of the transport of these nucleosides was insensitive to the classical mammalian nucleoside transport inhibitor nitrobenzylthioinosine (NBMPR). In vitro studies with tubercidin demonstrated ID50 values of 0.43 and 0.51 microM for FCQ-27 and K-1, respectively. In addition, the nucleoside transport inhibitors NBMPR, nitrobenzylthioguanosine (NBTGR), dilazep and dipyridamole also independently exhibited antimalarial activity in vitro. The combination of tubercidin and NBMPR or NBTGR in vitro demonstrated synergistic activity, whilst tubercidin together with dilazep or dipyridamole showed subadditive activity. Analysis by HPLC indicated that NBMPR could permeate the infected cell membrane and provided evidence for the catabolism of NBMPR in vitro, with subsequent alteration of the purine pool in the infected erythrocyte. These observations further indicated the possibility of the utilization of cytotoxic nucleosides against P. falciparum infection in conjunction with a nucleoside transport inhibitor to protect the host tissue.

  11. Urinary nucleosides as biological markers for patients with colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Yu-Fang Zheng; Jun Yang; Xin-Jie Zhao; Bo Feng; Hong-Wei Kong; Ying-Jie Chen; Shen Lv; Min-Hua Zheng; Guo-Wang Xu

    2005-01-01

    AIM: Fourteen urinary nucleosides, primary degradation products of tRNA, were evaluated to know the potential as biological markers for patients with colorectal cancer.METHODS: The concentrations of 14 kinds of urinary nucleosides from 52 patients with colorectal cancer, 10patients with intestinal villous adenoma and 60 healthy adults were determined by column switching high performance liquid chromatography method.RESULTS: The mean levels of 12 kinds of urinary nucleosides (except uridine and guanosine) in the patients with colorectal cancer were significantly higher than those in patients with intestinal villous adenoma or the healthy adults. Using the levels of 14 kinds of urinary nucleosides as the data vectors for principal component analysis, 71% (37/52) patients with colorectal cancer were correctly classified from healthy adults, in which the identification rate was much higher than that of CEA method (29%).Only 10% (1/10) of patients with intestinal villous adenoma were indistinguishable from patients with colorectal cancer. The levels of m1G, Pseu and m1A were positively related with tumor size and Duke's stages of colorectal cancer. When monitoring the changes in urinary nucleoside concentrations of patients with colorectal cancer associated with surgery, it was found that the overall correlations with clinical assessment were 84% (27/32)and 91% (10/11) in response group and progressive group, respectively.CONCLUSION: These findings indicate that urinary nucleosides determined by column switching high performance liquid chromatography method may be useful as biological markers for colorectal cancer.

  12. Flexibility as a Strategy in Nucleoside Antiviral Drug Design.

    Science.gov (United States)

    Peters, H L; Ku, T C; Seley-Radtke, K L

    2015-01-01

    As far back as Melville Wolfrom's acyclic sugar synthesis in the 1960's, synthesis of flexible nucleoside analogues have been an area of interest. This concept, however, went against years of enzyme-substrate binding theory. Hence, acyclic methodology in antiviral drug design did not take off until the discovery and subsequent FDA approval of such analogues as Acyclovir and Tenofovir. More recently, the observation that flexible nucleosides could overcome drug resistance spawned a renewed interest in the field of nucleoside drug design. The next generation of flexible nucleosides shifted the focus from the sugar moiety to the nucleobase. With analogues such as Seley-Radtke "fleximers", and Herdewijn's C5 substituted 2'-deoxyuridines, the area of base flexibility has seen great expansion. More recently, the marriage of these methodologies with acyclic sugars has resulted in a series of acyclic flex-base nucleosides with a wide range of antiviral properties, including some of the first to exhibit anti-coronavirus activity. Various flexible nucleosides and their corresponding nucleobases will be compared in this review.

  13. Antibacterial Effects of the Essential Oils of CommonlyConsumed Medicinal Herbs Using an In Vitro Model.

    NARCIS (Netherlands)

    Sokovic, M.; Glamoclija, J.; Marin, P.D.; Brkic, D.; Griensven, van L.J.L.D.

    2010-01-01

    The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determin

  14. Antibacterial effect of ginger (Zingiber officinale roscoe and bioactive chemical analysis using Gas chromatography mass spectrum

    Directory of Open Access Journals (Sweden)

    Hasanain Khaleel Shareef

    2016-05-01

    Full Text Available The objectives of this research was to determine the chemical composition of roscoe extract from methanol and evaluation of antibacterial activity. The phytochemical compound screened by GC-MS method. Forty eight bioactive phytochemical compounds were identified in the methanolic extract of Zingiber officinale. The identification of phytochemical compounds is based on the peak area, retention time molecular weight, molecular formula, MS Fragment-ions and pharmacological actions. GC-MS analysis of Zingiber officinale revealed the existence of the Octanal, 2-Naphthalenamine,1,2,4a,5,6,7,8,8a-octahydro-4a-methyl, 1-(Cyclopropyl-nitro-methyl-cyclopentanol, Endo-Borneol, Decanal, 1,2-15,16-Diepoxyhexadecane, Propanal,2-methyl-3-phenyl, Benzeneacetic acid ,4-(1H-1,2,3,4-tetrazol-1-yl, Ascaridole epoxide, 2-Methoxy-4-vinylphenol, 6-epi-shyobunol, Phenol,2-methoxy-5-(1-propenyl-,E, Alfa.-Copaene, 8-Isopropenyl-1,5-dimethyl-cyclodeca-1,5-diene, Bicyclo[3.1.0]hexane-6-methanol,2-hydroxy-1,4,4-trimethyl, 7-epi-cis-sesquisabinene hydrate, Alloaromadendrene, Benzene,1-(1,5-dimethyl-4-hexenyl-4-methyl, 1,3-Cyclohexadiene ,5-(1,5-dimethyl-4-hexenyl-2methyl-,[S-(R*,S*], Aromadendrene oxide, 1,6,10-Dodecatrien-3-ol,3,7,11-trimethyl-,(E, 4-((1H-3-Hydroxy-1-propenyl-2-methoxyphenol, Butan-2-one,4-(3-hydroxy-2-methoxyphenyl, Longipinocarveol,trans, Cholestan-3-ol,2-methylene-,(3ß,5α-, Bicyclo[4.4.0]dec-2-ene-4-ol,2-methyl-9-(prop-1-en-3-ol-2-yl-, Corymbolone, Estra-1,3,5(10-trien-17ß-ol, 1-Heptatriacotanol, Fenretinide, Folic acid, Spiro[4.5]decan-7-one,1,8-dimethyl-8,9-epoxy-4-isopropyl-, 7H-6,9a-Methano-4H-cyclopenta[9,10] cyclopropa[5,6]cyclodeca[1, Gingerol, 1b,4a-Epoxy-2H-cyclopenta[3,4]cyclopropa [8,9]cycloundec[1,2-b]o, Cyclopropa[5,6]-A-nor-5α-androstane-3,7-dione,3´,6ß-dihydro-17ß-h, Olean-12-ene-3,15,16,21,22,28-hexol,(3ß,15α,16α,21ß,22α-, Benz[e]azulen-3(3aH-one,4,6a,7,8,9,10,10a,10b-octahydro-3a,8,1, Naphthalene, decahydro-1-pentadecyl-, 13

  15. Effects of fractionation and combinatorial evaluation of Tamarindus indica fractions for antibacterial activity.

    Science.gov (United States)

    Nwodo, Uchechukwu U; Iroegbu, Christian U; Ngene, Augustine A; Chigor, Vincent N; Okoh, Anthony I

    2011-06-09

    Six fractions, named TiA - TiF, were obtained by fractionating the crude ethanol extract of the stem bark of Tamarindus indica using column chromatographic techniques. On TLC, fraction TiB showed five bands, TiC three bands, while TiD and TiE showed two bands each. TiC, TiD and TiE were re-eluted with different solvent systems to yield two fractions each, while TiB yielded four. These subfractions were designated B1-B4; C1-C2; D1-D2 and E1-E2, respectively. Tannins, flavonoids and alkaloids, among other components, were detected, albeit in different proportions with respect to fractions and subfractions and were compartmentalized with respect to the solvent systems used. The in vitro antibacterial activity of fractions and subfractions was tested separately and in combinations using the agar well diffusion technique. The susceptibly of test strains (expressed as %) were: 83.3% (TiA and TiB), 75.0% (crude extract and TiC), 66.7% (TiD), 50.0% (TiE) and 16.7% (TiF) when used singly, whereas in combination, the corresponding susceptibilities were 100% (CE), 83.3% (DE), 66.7% (AB, AF, BC, BD, DE and EF), 50% (AC and CD), 33.3% (BE and BF) and 16.7% (AD) against Gram negative bacteria strains and 100% (EF), 80% (DE), 60% (AB, BC and CE), 40% (AC, BD, BF, CF and DF) and 20% (AE, AF, BE and CD) against Gram positive strains. Percentage susceptibility with combinatorial use of re-fractions ranged from 85.7-57.1% and 60-40% against Gram negative and positive strains (TiB subfractions), respectively, 100-85.7% and 40-0% against Gram negative and positive strains (TiC, TiD and TiE sub-fractions).

  16. Synthesis of Ag doped calcium phosphate particles and their antibacterial effect as additives in dental glass ionomer cements

    OpenAIRE

    2016-01-01

    Developing dental restorations with enhanced antibacterial properties has been a constant quest for materials scientists. The aim of this study was to synthesize silver doped calcium phosphate particles and use them to improve antibacterial properties of conventional glass ionomer cement. The Ag doped monetite (Ag-DCPA) and hydroxyapatite (Ag-HA) were synthesized by precipitation method and characterized using X-ray diffraction, scanning electron microscope and X-ray fluorescence spectroscopy...

  17. Comparative study of antibacterial activity of wood-decay fungi and antibiotics

    OpenAIRE

    A. F. Md. Hassan Iftekhar; Zubaida Khatoon Choudhry; Md. Ismail Khan; Ahmed Abu Saleh

    2011-01-01

    The antibacterial effects of three mushrooms extract Ganoderma lucidum, Auricularia auricula, Pleurotus florida were studied against Staphylococcus aureus and Escherichia coli. A. auricula showed significant antibacterial activity against S. aureus. P. florida showed some antibacterial activity while G. lucidum showed no antibacterial activity. None of the extracts showed any activity against E. coli.

  18. Enhancing the antibiotic antibacterial effect by sub lethal tellurite concentrations: tellurite and cefotaxime act synergistically in Escherichia coli.

    Science.gov (United States)

    Molina-Quiroz, Roberto C; Muñoz-Villagrán, Claudia M; de la Torre, Erick; Tantaleán, Juan C; Vásquez, Claudio C; Pérez-Donoso, José M

    2012-01-01

    The emergence of antibiotic-resistant pathogenic bacteria during the last decades has become a public health concern worldwide. Aiming to explore new alternatives to treat antibiotic-resistant bacteria and given that the tellurium oxyanion tellurite is highly toxic for most microorganisms, we evaluated the ability of sub lethal tellurite concentrations to strengthen the effect of several antibiotics. Tellurite, at nM or µM concentrations, increased importantly the toxicity of defined antibacterials. This was observed with both gram negative and gram positive bacteria, irrespective of the antibiotic or tellurite tolerance of the particular microorganism. The tellurite-mediated antibiotic-potentiating effect occurs in laboratory and clinical, uropathogenic Escherichia coli, especially with antibiotics disturbing the cell wall (ampicillin, cefotaxime) or protein synthesis (tetracycline, chloramphenicol, gentamicin). In particular, the effect of tellurite on the activity of the clinically-relevant, third-generation cephalosporin (cefotaxime), was evaluated. Cell viability assays showed that tellurite and cefotaxime act synergistically against E. coli. In conclusion, using tellurite like an adjuvant could be of great help to cope with several multi-resistant pathogens.

  19. Cloning, Expression, and Purification of Nucleoside Diphosphate Kinase from Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Juhi Sikarwar

    2013-01-01

    Full Text Available Acinetobacter baumannii is a multidrug resistant pathogenic bacteria associated with hospital acquired infections. This bacterium possesses a variety of resistance mechanisms which makes it more difficult to control the bacterium with conventional drugs, and, so far no effective drug treatment is available against it. Nucleoside diphosphate kinase is an important enzyme, which maintains the total nucleotide triphosphate pool inside the cell by the transfer of γ-phosphate from NTPs to NDPs. The role of nucleoside diphosphate kinase (Ndk has also been observed in pathogenesis in other organisms. However, intensive studies are needed to decipher its other putative roles in Acinetobacter baumannii. In the present study, we have successfully cloned the gene encoding Ndk and achieved overexpression in bacterial host BL-21 (DE3. The overexpressed protein is further purified by nickel-nitrilotriacetic acid (Ni-NTA chromatography.

  20. Cloning, Expression, and Purification of Nucleoside Diphosphate Kinase from Acinetobacter baumannii

    Science.gov (United States)

    Sikarwar, Juhi; Kaushik, Sanket; Sinha, Mau; Kaur, Punit; Sharma, Sujata; Singh, Tej P.

    2013-01-01

    Acinetobacter baumannii is a multidrug resistant pathogenic bacteria associated with hospital acquired infections. This bacterium possesses a variety of resistance mechanisms which makes it more difficult to control the bacterium with conventional drugs, and, so far no effective drug treatment is available against it. Nucleoside diphosphate kinase is an important enzyme, which maintains the total nucleotide triphosphate pool inside the cell by the transfer of γ-phosphate from NTPs to NDPs. The role of nucleoside diphosphate kinase (Ndk) has also been observed in pathogenesis in other organisms. However, intensive studies are needed to decipher its other putative roles in Acinetobacter baumannii. In the present study, we have successfully cloned the gene encoding Ndk and achieved overexpression in bacterial host BL-21 (DE3). The overexpressed protein is further purified by nickel-nitrilotriacetic acid (Ni-NTA) chromatography. PMID:23662205

  1. The effect of doping titanium dioxide nanoparticles on phase transformation, photocatalytic activity and anti-bacterial properties

    Science.gov (United States)

    Buzby, Scott Edward

    . Dopant ions with larger radii than titanium stress the crystal lattice promoting anatase formation, since it has a larger c/a ratio than rutile does. The cation dopants were also found to decrease the average particle size of the titanium dioxide nanoparticles. The defect sites caused by the doping prevent the nucleation and retard particle growth of titanium dioxide particles. Cation doping of titanium dioxide nanoparticles affect other properties of the nanoparticles besides the phase transitions. For example titanium dioxide doped with magnetic materials such as Fe, Ni, Co or Cr has been shown to display room temperature ferromagnetism which are currently being studied for use in spintronic devices. The antibacterial studies of silver doped titanium dioxide nanoparticles were carried out against Escherichia coli, both in nutrient solution and on agar-plates. Both studies show that while pure titanium dioxide has no antibacterial effect, when doped with as little as 0.72 atomic % silver becomes more effective than pure silver nanoparticles of similar size. It has been observed that with concentrations as low as 25mug/cm 2 of silver doped titanium dioxide, completely antibacterial surfaces may be synthesized.

  2. Evaluation of the Antibacterial Effects of Flavonoid Combination from the Leaves of Dracontomelon dao by Microcalorimetry and the Quadratic Rotary Combination Design

    Science.gov (United States)

    Li, Yang; Xia, Houlin; Wu, Mingquan; Wang, Jiabo; Lu, Xiaohua; Wei, Shizhang; Li, Kun; Wang, Lifu; Wang, Ruilin; Zhao, Pan; Zhao, Yanling; Xiao, Xiaohe

    2017-01-01

    Skin infectious disease is a common public health problem due to the emergence of drug-resistant bacteria caused by the antibiotic misuse. Dracontomelon dao (Blanco) Merr. et Rolfe, a traditional Chinese medicine, has been used for the treatment of various skin infectious diseases over 1000 of years. Previous reports have demonstrated that the leaves of D. dao present favorable antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtitles. The flavonoids are the main components of the ethyl acetate extract of D. dao leaf. However, the correlation between flavonoids and antibacterial activities is yet to be determined. In this study, the combined antibacterial activities of these flavonoids were investigated. Three samples with the different concentrations of flavonoids (S1–S3) were obtained. By microcalorimetric measurements, the results showed that the IC50 value of S2 was lower than those of S1 and S3. The contents of main flavonoids (including Luteolin, L-Epicatechin, Cianidanol, and Quercetin) in S1–S3 were various, confirmed by the method of the Ultra High Performance Liquid Chromatography (UPLC). Based on the method of quadratic general rotary unitized design, the antibacterial effect of single flavonoid, and the potential synergistic effects between Luteolin and Quercetin, Luteolin and Cianidanol were calculated, which were also proved by microcalorimetric analysis. The antibacterial activities of main flavonoids were Luteolin > Cianidanol > Quercetin > L-Epicatechin. Meanwhile, the synergistic effects of Luteolin and Cianidanol (PL+C = 1.425), Quercetin and Luteolin (PL+Q = 1.129) on anti-microbial activity were validated. Finally, we found that the contents of Luteolin, L-Epicatechin, Cianidanol, Quercetin were 1061.00–1061.00, 189.14–262.86, 15,990.33–16,973.62, 6799.67–7662.64 ng·ml−1 respectively, with the antibacterial rate over 60.00%. In conclusion, this study could provide

  3. Antibacterial Effect of CrO and CoFe2O4 Nanoparticles upon Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Saber Imani

    2011-12-01

    Full Text Available Background & Objectives: The use of metal oxide nanoparticles can be effective to eliminate the bacterial infections, as an alternative to antibiotics. In this study, antibacterial properties of nonmaterials of CrO and CoFe2O4 are investigated against Staphylococcus aureus as a major and prevalent pathogenic bacterium to achieve sterile nano-containers. Materials & Methods: Different concentrations of CrO and CoFe2O4 nanoparticles, (0.2, 0.4, 0.6, 0.8, and 1% of each, were examined with respect to their optical density (OD culture separately. Different percentages of each nanoparticles were also examined together for the best antibacterial combination. Kinetics of Bactericidal of nanoparticles were calculated in two-hour periods and were compared with the power of other common antibiotics. Ratios of MIC/MBC were calculated by Micro dilution method, to demonstrate the bactericidal power of nanoparticles. Results: The best concentration of the nanoparticles with the highest effect of bactericidal was obtained in the presence of 1% concentration of CrO that the OD of S. aureus culture medium had reduced 4/6 times than the control group (p<0/001.Ratio of 70% CrO to 30% CoFe2O4 was the best of the Bacteriostatic properties that OD was reduced 3/3 times than the control group (p<0/05. Best kinetics of bactericidal with survival rate in the presence of 1% CrO and CoFe2O4 were obtained in 24 and 36 hours respectively. In critical concentration of 1% CrO and CoFe2O4 bactericidal power was about 67 and 56 % respectively. The MIC/MBC rate for CrO and CoFe2O4 was obtained 0/2 and 0/4 respectively. Conclusion: The results showed that CrO nanoparticle compared with CoFe2O4 has a higher bactericidal power for S. aureus infection. Therefore, by completion of these experiments and the use of metal oxide nanoparticles complex in sensitive environments such as food storage containers, etc. are suggested.

  4. Effect of a Novel Quaternary Ammonium Methacrylate Polymer (QAMP on Adhesion and Antibacterial Properties of Dental Adhesives

    Directory of Open Access Journals (Sweden)

    Yasmine M. Pupo

    2014-05-01

    control for all evaluated bacterial strains. The use of QAMP in an adhesive system demonstrated effective bond strength, a suitable degree of conversion, and adequate antibacterial effects against oral bacteria, and may be useful as a new approach to provide long-lasting results for dental adhesives.

  5. Human concentrative nucleoside transporter 1-mediated uptake of 5-azacytidine enhances DNA demethylation.

    Science.gov (United States)

    Rius, Maria; Stresemann, Carlo; Keller, Daniela; Brom, Manuela; Schirrmacher, Esther; Keppler, Dietrich; Lyko, Frank

    2009-01-01

    The DNA methyltransferase inhibitors 5-azacytidine (5-azaCyd) and 5-aza-2'-deoxycytidine have found increasing use for the treatment of myeloid leukemias and solid tumors. Both nucleoside analogues must be transported into cells and phosphorylated before they can be incorporated into DNA and inactivate DNA methyltransferases. The members of the human equilibrative and concentrative nucleoside transporter families mediate transport of natural nucleosides and some nucleoside analogues into cells. However, the molecular identity of the transport proteins responsible for mediating the uptake of 5-azanucleosides has remained unknown. To this end, we have generated a stably transfected Madin-Darby canine kidney strain II cell line expressing recombinant hCNT1. An antiserum directed against hCNT1 specifically detected the protein in the apical membrane of hCNT1-expressing Madin-Darby canine kidney cells. Using [14C]5-azaCyd, we show here that hCNT1 mediated the Na+-dependent uptake of this drug with a Km value of 63 micromol/L. Na+-dependent transport of radiolabeled cytidine, uridine, and 5-fluoro-5'-deoxyuridine further showed the functionality of the transporter. hCNT1-expressing cells were significantly more sensitive to 5-azaCyd, and drug-dependent covalent trapping of DNA methyltransferase 1 was substantially more pronounced. Importantly, these results correlated with a significant sensitization of hCNT1-expressing cells toward the demethylating effects of 5-azaCyd and 5-aza-2'-deoxycytidine. In conclusion, our study identifies 5-azaCyd as a novel substrate for hCNT1 and provides direct evidence that hCNT1 is involved in the DNA-demethylating effects of this drug.

  6. Toxicity of nucleoside analogues used to treat AIDS and the selectivity of the mitochondrial DNA polymerase.

    Science.gov (United States)

    Lee, Harold; Hanes, Jeremiah; Johnson, Kenneth A

    2003-12-23

    Incorporation of nucleoside analogues by the mitochondrial DNA polymerase has been implicated as the primary cause underlying many of the toxic side effects of these drugs in HIV therapy. Recent success in reconstituting recombinant human enzyme has afforded a detailed mechanistic analysis of the reactions governing nucleotide selectivity of the polymerase and the proofreading exonuclease. The toxic side effects of nucleoside analogues are correlated with the kinetics of incorporation by the mitochondrial DNA polymerase, varying over 6 orders of magnitude in the sequence zalcitabine (ddC) > didanosine (ddI metabolized to ddA) > stavudine (d4T) > lamivudine (3TC) > tenofovir (PMPA) > zidovudine (AZT) > abacavir (metabolized to carbovir, CBV). In this review, we summarize our current efforts to examine the mechanistic basis for nucleotide selectivity by the mitochondrial DNA polymerase and its role in mitochondrial toxicity of nucleoside analogues used to treat AIDS and other viral infections. We will also discuss the promise and underlying challenges for the development of new analogues with lower toxicity.

  7. Empirical prediction and validation of antibacterial inhibitory effects of various plant essential oils on common pathogenic bacteria.

    Science.gov (United States)

    Akdemir Evrendilek, Gulsun

    2015-06-02

    In this study, fractional compound composition, antioxidant capacity, and phenolic substance content of 14 plant essential oils-anise (Pimpinella anisum), bay leaves (Laurus nobilis), cinnamon bark (Cinnamomum verum), clove (Eugenia caryophyllata), fennel (Foeniculum vulgare), hop (Humulus lupulus), Istanbul oregano (Origanum vulgare subsp. hirtum), Izmir oregano (Origanum onites), mint (Mentha piperita), myrtus (Myrtus communis), orange peel (Citrus sinensis), sage (Salvia officinalis), thyme (Thymbra spicata), and Turkish oregano (Origanum minutiflorum)--were related to inhibition of 10 bacteria through multiple linear or non-linear (M(N)LR) models-four Gram-positive bacteria of Listeria innocua, coagulase-negative staphylococci, Staphylococcus aureus, and Bacillus subtilis, and six Gram-negative bacteria of Yersinia enterocolitica, Salmonella Enteritidis, Salmonella Typhimurium, Proteus mirabilis, Escherichia coli O157:H7, and Klebsiella oxytoca. A total of 65 compounds with different antioxidant capacity, phenolic substance content and antibacterial properties were detected with 14 plant essential oils. The best-fit M(N)LR models indicated that relative to anise essential oil, the essential oils of oreganos, cinnamon, and thyme had consistently high inhibitory effects, while orange peel essential oil had consistently a low inhibitory effect. Regression analysis indicated that beta-bisabolene (Turkish and Istanbul oreganos), and terpinolene (thyme) were found to be the most inhibitory compounds regardless of the bacteria type tested.

  8. Antibacterial effect of mango (Mangifera indica Linn.) leaf extract against antibiotic sensitive and multi-drug resistant Salmonella typhi.

    Science.gov (United States)

    Hannan, Abdul; Asghar, Samra; Naeem, Tahir; Ikram Ullah, Muhammad; Ahmed, Ijaz; Aneela, Syeda; Hussain, Shabbir

    2013-07-01

    Alternative herbal medicine has been used to treat various infections from centuries. Natural plants contain phytoconstituents having similar chemical properties as of synthetic antibiotics. Typhoid fever is a serious infection and failure of its treatment emerged multi-drug resistant (MDR) bugs of Salmonella typhi. Due to multiple and repeated issues with antibiotics efficacy, it became essential to evaluate biological properties of plants from different geographical origins. Mango leaves have been Reported for various medicinal effects like antioxidant, antimicrobial, antihelminthic, antidiabetic and antiallergic etc. Objective of present study was to investigate anti-typhoid properties of acetone mango leaf extract (AMLE) against antibiotic sensitive and MDR S. typhi isolates. A total of 50 isolates of S. typhi including MDR (n=30) and antibiotic sensitive (n=20) were investigated. Staphylococcus aureus (ATCC 25923) and Salmonella typhimurium (ATCC14028) were used as quality control strains. AMLE was prepared and its antibacterial activity was evaluated by agar well diffusion screening method and minimum inhibitory concentration (MIC), by agar dilution technique. Zone of inhibition (mm) of AMLE against MDR and antibiotic sensitive isolates was 18±1.5mm (Mean±S.D). Zone of S. aureus (ATCC 25923) and S. typhimurium (ATCC14028) was 20±1.5mm (Mean±S.D). MIC of AMLE was Reported in range from 10-50 mg/ml. The present study described the inhibitory effects of mango leaves against S. typhi.

  9. The antibacterial effect of sage extract (Salvia officinalis mouthwash against Streptococcus mutans in dental plaque: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Maryam Beheshti-Rouy

    2015-11-01

    Full Text Available Background and Objective:  The aim of the study was to evaluate the clinical effects of a mouthwash containing Sage (Salvia officinalis extracts on Streptococcus mutans (SM causing dental plaque in school-aged children.Material and Methods: A double blind clinical trial study was conducted in a dormitory on 70 girls aged 11-14 years having the same socioeconomic and oral hygiene conditions. These students were randomly divided into 2 groups; the first group (N=35 using Sage mouthwash, and the second group (N=35 using placebo mouthwash without active any ingredients. At the baseline, plaque samples obtained from the buccal surfaces of teeth were sent to laboratory to achieve SM colony count. These tests were reevaluated after 21 days of using the mouthwashes. Statistical data analysis was performed using t-student tests with p<0.05 as the level of significance.Results: Sage mouthwash significantly reduced the colony count (P=0.001. Average number of colonies in test group was 3900 per plaque sample at the baseline, and 300 after mouthwash application. In the control group, pre-test colony count was 4400 that was reduced to 4000; although this reduction wasn’t significant.Conclusion: The Sage mouthwash effectively reduced the number of Streptococcus mutans in dental plaque.Keywords: anti-bacterial agents; dental plaque; Salvia officinalis; Streptococcus mutans

  10. Antibacterial Effects and Mode of Action of Selected Essential Oils Components against Escherichia coli and Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Julio Cesar Lopez-Romero

    2015-01-01

    Full Text Available Bacterial resistance has been increasingly reported worldwide and is one of the major causes of failure in the treatment of infectious diseases. Natural-based products, including plant secondary metabolites (phytochemicals, may be used to surpass or reduce this problem. The objective of this study was to determine the antibacterial effect and mode of action of selected essential oils (EOs components: carveol, carvone, citronellol, and citronellal, against Escherichia coli and Staphylococcus aureus. The minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC were assessed for the selected EOs components. Moreover, physicochemical bacterial surface characterization, bacterial surface charge, membrane integrity, and K+ leakage assays were carried out to investigate the antimicrobial mode of action of EOs components. Citronellol was the most effective molecule against both pathogens, followed by citronellal, carveol, and carvone. Changes in the hydrophobicity, surface charge, and membrane integrity with the subsequent K+ leakage from E. coli and S. aureus were observed after exposure to EOs. This study demonstrates that the selected EOs have significant antimicrobial activity against the bacteria tested, acting on the cell surface and causing the disruption of the bacterial membrane. Moreover, these molecules are interesting alternatives to conventional antimicrobials for the control of microbial infections.

  11. Effect of Infusions of Non-Antibiotic Antibacterials Alone and in Combination with Cephradine on Milk Yield of Buffaloes Affected with Clinical Mastitis

    Directory of Open Access Journals (Sweden)

    M. Yousaf*, G. Muhammad1, M. Z. Khan2 and S. U. Rahman3

    2010-01-01

    Full Text Available The objective of the present study was to evaluate the effect of four non-antibiotic antibacterials alone or in combination with cephradine in buffaloes on milk yield of mastitis affected quarters. For this purpose, 270 clinically mastitic quarters were grouped in randomized pattern. Non-antibiotic antibacterials viz., 2.5% chlorpromazine (2 ml, 4% lidocaine (10 ml, 10% povidone-iodine (10 ml and 99.5% dimethylsulphoxide (20 ml alone and in combination with first generation cephalosporin (cephradine 500 mg were instilled into clinically mastitic quarters daily for five days. The group administered cephradine alone served as control. Mean milk yield (L/quarter per day was recorded before administration of treatment and over a period of 4 weeks post initiation of treatment. Among the 4 non-antibiotic antibacterials tested alone, chlorpromazine (CPZ showed significantly higher (P<0.05 recuperative effect on the milk yield of clinically mastitic quarters of dairy buffaloes. However, dimethylsulphoxide (DMSO when infused alone, further aggravated (P<0.05 the milk yield loss, indicating negative effect on milk yield improvement. Adjuncting cephradine with each of the non-antibiotic antibacterials, the lidocaine-cephradine group showed the highest effect (p<0.05 on net recovery of milk yield on day 28 post initiation of treatment. It was concluded that that CPZ can be used in clinical mastitis in buffaloes as a low cost alternative to expensive branded antibiotics. Further, the use of lidocaine with cepheradnie was superior to all other combination regimens in milk yield recovery.

  12. Effects of Fractionation and Combinatorial Evaluation of Tamarindus indica Fractions for Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Augustine A. Ngene

    2011-06-01

    Full Text Available Six fractions, named TiA – TiF, were obtained by fractionating the crude ethanol extract of the stem bark of Tamarindus indica using column chromatographic techniques. On TLC, fraction TiB showed five bands, TiC three bands, while TiD and TiE showed two bands each. TiC, TiD and TiE were re-eluted with different solvent systems to yield two fractions each, while TiB yielded four. These subfractions were designated B1-B4; C1-C2; D1-D2 and E1-E2, respectively. Tannins, flavonoids and alkaloids, among other components, were detected, albeit in different proportions with respect to fractions and subfractions and were compartmentalized with respect to the solvent systems used. The in vitro antibacterial activity of fractions and subfractions was tested separately and in combinations using the agar well diffusion technique. The susceptibly of test strains (expressed as % were: 83.3% (TiA and TiB, 75.0% (crude extract and TiC, 66.7% (TiD, 50.0% (TiE and 16.7% (TiF when used singly, whereas in combination, the corresponding susceptibilities were 100% (CE, 83.3% (DE, 66.7% (AB, AF, BC, BD, DE and EF, 50% (AC and CD, 33.3% (BE and BF and 16.7% (AD against Gram negative bacteria strains and 100% (EF, 80% (DE, 60% (AB, BC and CE, 40% (AC, BD, BF, CF and DF and 20% (AE, AF, BE and CD against Gram positive strains. Percentage susceptibility with combinatorial use of re-fractions ranged from 85.7–57.1% and 60–40% against Gram negative and positive strains (TiB subfractions, respectively, 100–85.7% and 40–0% against Gram negative and positive strains (TiC, TiD and TiE sub-fractions.

  13. Structural properties and antibacterial effects of hydrophobic and oleophobic sol-gel coatings for cotton fabrics.

    Science.gov (United States)

    Vilcnik, Aljaz; Jerman, Ivan; Surca Vuk, Angela; Kozelj, Matjaz; Orel, Boris; Tomsic, Brigita; Simoncic, Barbara; Kovac, Janez

    2009-05-19

    In a continuation of previous studies, the wetting properties of the hydrophobic diureapropyltriethoxysilane [bis(aminopropyl)-terminated polydimethylsiloxane (1000)] (PDMSU) sol-gel hybrid, which forms washing-resistant water-repellent finishes on cotton fabrics, were further investigated. The addition of 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) to PDMSU resulted in a highly apolar low-energy surface on aluminum with gammaStotal equal to 14.5 mJ/m2 and a DetlaGiwi value of -82 mJ/m2. Mixed PFOTES-PDMSU finishes applied on cotton fabrics increased the water contact angles (thetaw) from approximately 130 degrees (PDMSU) to 147 degrees, also imparting oleophobicity (thetadiiodomethane=130 degrees, thetan-hexadecane=120 degrees) to the finished cotton fabrics. Washing caused breakage of the coating's integrity as established from SEM, which was attributed to the partial removal of PFOTES from the composite films, also shown by subtractive IR attenuated total reflectance (ATR) and XPS spectral measurements made on washed and unwashed fabrics. The antibacterial properties of the PFOTES-PDMSU-finished fabrics were assessed with the transfer method (EN ISO 20743:2007), revealing that the reduction of Escherichia coli bacteria on unwashed cotton fabrics was nearly 100%. Moreover, for washed (10 times) cotton fabrics a much higher bacterial reduction was noted for the PFOTES-PDMSU finishes (60.6+/-10.8%), surpassing PDMSU (30.4+/-6.1%) and commercial fluoroalkoxysilane (FAS) (21.9+/-5.7%) finishes. The structure of PFOTES-PDMSU gels, xerogels, and the corresponding coatings was investigated by analyzing the 29Si NMR and IR ATR spectra and comparing them with the spectra of PFOTES and octameric (T8) PFOTES based polyhedra. The results revealed the tendency of PFOTES to condense in octameric silsesquioxane polyhedra (T8), coexisting in the PDMSU sol-gel network with cyclic tetramers (T4(OH)4) and open cube-like species (T7(OH)3). The presence of -OH

  14. 香辛料精油复配抑菌效果研究%Research on the Antibacterial Effect of Essential Oil from Spices and Herbs

    Institute of Scientific and Technical Information of China (English)

    杨柳; 张一; 王磊; 陈宇飞; 李玉邯; 边忠博; 李秉峰

    2016-01-01

    The antibacterial effect of essential oil from spices and herbs is studied.Through the antibacterial test of the single essential oil from clove,cinnamon,nutmeg,cumin and fennel on Escherichiacoli,Staphylococcusaureus,Saccharomycescerevisiae and Aspergillusniger, the antibacterial test of clove,cinnamon and their compound essential oils on four types of bacteria and the antibacterial stability test of the compound essential oils on Escherichiacoliand Aspergillusniger under different temperatures and pH,the results show that the antibacterial abilities of clove and cinnamon essential oils are strong,which are stronger than several other essential oils from spices and herbs.The effect of the compound essential oils inhibiting Escherichiacoliand Aspergillusnigeris obvious.The antibacterial activity of the compound essential oils under different temperatures and pH is stable,which has provided a reference for the application of compound essential oils as bacteriostat in food.%研究香辛料精油复配的抑菌效果。利用丁香、肉桂、豆蔻、孜然、茴香5种香辛料分别对大肠杆菌、金黄色葡萄球菌、啤酒酵母、黑曲霉菌单一精油的抑菌试验;丁香、肉桂及二者复配3种精油验对4种菌的抑菌试验;复配精油在不同温度、pH 下对大肠杆菌和黑曲霉菌的抑菌稳定性试验,得出丁香精油抑制细菌、肉桂精油抑制真菌的能力较强,均高于其他几种香辛料精油的抑菌能力;复配精油对大肠杆菌、黑曲霉的抑菌效果明显;且复配精油在不同温度和pH 下抑菌性较为稳定,为复配精油作为抑菌剂在食品中的应用提供参考。

  15. 21种中草药提取物对MRSA的抗菌作用研究%Antibacterial Effects of 21 Extracts of Chinese Herbal Medicine on MRSA

    Institute of Scientific and Technical Information of China (English)

    傅若秋; 余琼; 孟德胜; 卢来春; 张雪梅

    2011-01-01

    目的:研究21种中草药提取物对11株耐甲氧西林金黄色葡萄球菌(MRSA)的体外抗茵作用.方法:采用96孔板培养法和涂片法测定各提取物对MRSA的抑茵率及杀菌率.结果:仙鹤草、半枝莲、夏枯草等8种中草药对MRSA具有较强的抗菌活性,其中仙鹤草醇提物、半枝莲水提物抑茵活性最强,浓度为6.25 mg·mL-1时抑茵率均达100%;仙鹤草水提物的杀茵活性最强,浓度为25 mg·mL-1时杀菌率迭100%.结论:仙鹤草、半枝莲提取物具有明显的抗MRSA作用.%OBJECTIVE: To study the antibacterial effects of 21 extracts of Chinese herbal medicine on MRS A in vitro. METHODS: The antibacterial ratio and bactericidal rate of each extract of Chinese herbal medicine were determined by 96-well multiwell plates and direct smear method. RESULTS: 8 Chinese herbal medicines had antibacterial activities on MRSA, such as Agrimoniapi-losa, Scutellaria barbata and Prunella vulgaris. The ethanol extracts of A. Pilosa and water extracts of S. Barbata had the strongest antibacterial activity, and the antibacterial ratio of them reached 100% as the concentrations of them were 6.25 mg·mL'-1 The bactericidal rate of water extracts of A. Pilosa was the highest, reaching 100% as the concentration of it was 25 mg·mL'-1 CONCLUSION: The extracts of A. Pilosa and S. Barbata show clear antibacterial effects on MRSA.

  16. Dynamic Expressions of Liver Tissue Apoptosis-related Genes of Vibrio Vulnificus Sepsis Rats and the Effects of Antibacterial Agents

    Institute of Scientific and Technical Information of China (English)

    Zhongqiu LU; Mengfang LI; Huan LIANG; Qiaomeng QIU; Guangtian YANG; Tieli ZHOU; Guangliang HONG

    2009-01-01

    Dynamic changes in mRNA expressions of liver tissue apoptosis-promoting genes Fas and Bax and apoptosis-inhibiting gene Bcl-2 of vibrio vulnificus sepsis rats were detected and the effects of antibacterial agents were examined.The rat model with Vibrio vulnificus sepsis (VV group) was established and some of the Vibrio vulnificus sepsis rats were treated with antibacterial agents (AA group).The mRNA expressions of Fas,Bax and Bcl-2 were measured by reverse transcription polymerase chain reaction (RT-PCR).As compared with normal control group (NC group),the expressions of Fas and Bax mRNA in liver tissue at all different time points in VV group were increased significantly (P<0.05),and the highest levels of Fas and Bax mRNA expressions were 6 and 12 h after the infection,respectively.At the same time,the expression of Bcl-2 mRNA in liver tissue at all different time points in VV group were decreased significantly (P<0.05),and the lowest level of Bcl-2 mRNA expression appeared 2 h after the infection.The mRNA expressions of Bcl-2 in liver tissue 9 and 12 h after the infection in AA group were increased significantly (P<0.05) compared with NC group,while the expressions of Fas and Bax mRNA were not significantly different from those of NC group.Compared with VV group,the expression of Fas mRNA in AA group was decreased (P<0.05) and Bax mRNA was decreased significantly 12 and 16 h after the infection (P<0.05),while the expressions of Bcl-2 mRNA were increased significantly 9,12 and 16 h after the infection (P<0.05).It is concluded that the mRNA expressions of liver tissue apoptosis-promoting genes Fas and Bax were increased remarkably in vibrio vulnificus sepsis rats,whereas the expression of apoptosis-inhibiting gene Bcl-2 mRNA was decreased obviously in sepsis rats in early stage.The treatment with cefoperazone sodium and levofloxacin lactate could inhibit the expression of Fas mR.NA and Bax mRNA and enhance the expression of Bcl-2 mRNA at the same time.

  17. Pyrimidine non-nucleoside analogs: A direct synthesis of a novel class of N-substituted amino and N-sulfonamide derivatives of pyrimidines.

    Science.gov (United States)

    Elgemeie, Galal H; Salah, Ali M; Abbas, Nermeen S; Hussein, Hoda A; Mohamed, Reham A

    2017-03-04

    A convenient method for the regioselective synthesis of pyrimidine non-nucleoside analogs was developed. This study reports a novel and efficient method for the synthesis of a new type of N-substituted amino methylsulfanylpyrimidines and the corresponding pyrazolo[3,4-d]pyrimidines. This series of compounds was designed through the reaction of dimethyl N-cyanodithioiminocarbonate with 2-cyano-N'-(thiophen-2-yl-, furan-2-yl- and pyridin-4-ylmethylene)acetohydrazide and N'-(2-cyanoacetyl)arylsulfonohydrazides. The scope and limitation of the method are demonstrated. The antibacterial and antifungal activities of the synthesized compounds were also evaluated.

  18. Investigating the role of nucleoside transporters in the resistance of colorectal cancer to 5-fluorouracil therapy.

    Science.gov (United States)

    Phua, Lee Cheng; Mal, Mainak; Koh, Poh Koon; Cheah, Peh Yean; Chan, Eric Chun Yong; Ho, Han Kiat

    2013-03-01

    Resistance to 5-fluorouracil (5FU) poses a constant challenge to the management of colorectal cancer (CRC). Consistent efforts were called for to identify molecular markers that can effectively predict patients' response. This study investigated the role of nucleoside transporters, particularly human equilibrative nucleoside transporter 1 (hENT1), in predicting clinical treatment outcome with 5FU-based therapy. Expression of a panel of nucleoside transporters in biopsied tumors from 7 CRC patients was measured by real-time PCR prior to 5FU-based chemotherapy. To provide mechanistic support for the role of hENT1 in 5FU resistance, cell viability of Caco-2 cells was measured, following incubation with varying concentrations of 5FU and a hENT1 inhibitor. Biopsied tumors were further subjected to global metabonomic profiling using gas chromatography/mass spectrometry. High hENT1 levels in tumor tissue correlated with poor clinical response to 5FU. Corroborating with the clinical findings, chemical inhibition of hENT1 in Caco-2 cells resulted in an augmentation of 5FU efficacy. Metabonomic profiling revealed that the pretreatment metabotype associated with non-responders to 5FU therapy was distinct from metabotype of responders (partial least-squares discriminant analysis Q(2) (cumulative) = 0.898, R(2)X = 0.513, R(2)Y = 0.996). This is the first clinical report on the relationships of intratumoral expression of nucleoside transporters and tumor metabotype with response to 5FU among CRC patients. Coupled to the in vitro findings, our preliminary data suggested hENT1 to be a potential codeterminant of clinical response to 5FU.

  19. Antibacterial activity of Tribulus terrestris and its synergistic effect with Capsella bursa-pastoris and Glycyrrhiza glabra against oral pathogens: an in-vitro study

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    Saman Soleimanpour

    2015-04-01

    Full Text Available Objective: In this study, antimicrobial activities of an ethanol extract of Tribulus terrestris aloneand in combination with Capsella bursa-pastoris and Glycyrrhiza glabra were examined in vitro against six pathogens namely Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus, Enterococcus faecalis Staphylococcus aureus, and Escherichia coli. Materials and methods: Antibacterial activities of the extracts were examined using disc and well diffusion methods and the minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC of ethanol extracts were determined against these microorganisms using agar and broth dilution methods. Chlorhexidine was used as positive control. Results: Tribulus terrestris extract exhibited good antibacterial activity against all bacteria. Antibacterial activity of mixed extract was evaluated and exhibited that mixed extract was more effective against all bacteria than any of the cases alone which indicates the synergistic effect between these three extracts (p˂0.05. No strain showed resistance against these extracts. In agar dilution, Tribulus terrestris exhibited MIC values ranging from 35.0 to 20.0 mg/ml and mixed extract showed MIC values ranging from 12.5 to 5.0 mg/ml. The results of broth dilution method were consistent with the findings of the agar dilution method. Conclusion: This in-vitro study was a preliminary evaluation of antibacterial activity of the plants. It provided scientific evidence to support uses of T. terrestris and its mixture with C. bursa-pastoris and G. glabra for the treatment of oral infections. In-vivo studies are also required to better evaluate the effect of these extracts.

  20. Distribution of Nucleosides in Populations of Cordyceps cicadae

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    Wen-Bo Zeng

    2014-05-01

    Full Text Available A rapid HPLC method had been developed and used for the simultaneous determination of 10 nucleosides (uracil, uridine, 2'-deoxyuridine, inosine, guanosine, thymidine, adenine, adenosine, 2'-deoxyadenosine and cordycepin in 10 populations of Cordyceps cicadae, in order to compare four populations of Ophicordyceps sinensis and one population of Cordyceps militaris. Statistical analysis system (SAS 8.1 was used to analyze the nucleoside data. The pattern of nucleoside distribution was analyzed in the sampled populations of C. cicadae, O. sinensis and C. militaris, using descriptive statistical analysis, nested analysis and Q cluster analysis. The total amount of the 10 nucleosides in coremium was 1,463.89–5,678.21 µg/g in 10 populations of C. cicadae, 1,369.80–3,941.64 µg/g in sclerotium. The average contents of the 10 analytes were 4,392.37 µg/g and 3,016.06 µg/g in coremium and sclerotium, respectively. The coefficient of variation (CV of nucleosides ranged from 8.36% to 112.36% in coremium of C. cicadae, and from 10.77% to 155.87% in sclerotium of C. cicadae. The CV of the nucleosides was wide within C. cicadae populations. The nested variation analysis by the nine nucleosides’ distribution indicated that about 42.29% of the nucleoside variability in coremium was attributable to the differentiation among populations, and the remaining 57.71% resided in the populations. It was also shown that about 28.94% of the variation in sclerotium was expressed between populations, while most of the variation (71.06% corresponded to the populations.

  1. In Silico Investigation of Flavonoids as Potential Trypanosomal Nucleoside Hydrolase Inhibitors

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    Christina Hung Hung Ha

    2015-01-01

    Full Text Available Human African Trypanosomiasis is endemic to 37 countries of sub-Saharan Africa. It is caused by two related species of Trypanosoma brucei. Current therapies suffer from resistance and public accessibility of expensive medicines. Finding safer and effective therapies of natural origin is being extensively explored worldwide. Pentamidine is the only available therapy for inhibiting the P2 adenosine transporter involved in the purine salvage pathway of the trypanosomatids. The objective of the present study is to use computational studies for the investigation of the probable trypanocidal mechanism of flavonoids. Docking experiments were carried out on eight flavonoids of varying level of hydroxylation, namely, flavone, 5-hydroxyflavone, 7-hydroxyflavone, chrysin, apigenin, kaempferol, fisetin, and quercetin. Using AutoDock 4.2, these compounds were tested for their affinity towards inosine-adenosine-guanosine nucleoside hydrolase and the inosine-guanosine nucleoside hydrolase, the major enzymes of the purine salvage pathway. Our results showed that all of the eight tested flavonoids showed high affinities for both hydrolases (lowest free binding energy ranging from −10.23 to −7.14 kcal/mol. These compounds, especially the hydroxylated derivatives, could be further studied as potential inhibitors of the nucleoside hydrolases.

  2. Antibacterial Activity, Antioxidant Effect and Chemical Composition of Propolis from the Región del Maule, Central Chile

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    Nélida Nina

    2015-10-01

    Full Text Available Propolis is commercialized in Chile as an antimicrobial agent. It is obtained mainly from central and southern Chile, but is used for the same purposes regardless of its origin. To compare the antimicrobial effect, the total phenolic (TP, the total flavonoid (TF content and the phenolic composition, 19 samples were collected in the main production centers in the Región del Maule, Chile. Samples were extracted with MeOH and assessed for antimicrobial activity against Gram (+ and Gram (− bacteria. TP and TF content, antioxidant activity by the DPPH, FRAP and TEAC methods were also determined. Sample composition was assessed by HPLD-DAD-ESI-MS/MS. Differential compounds in the samples were isolated and characterized. The antimicrobial effect of the samples showed MICs ranging from 31.5 to > 1000 µg/mL. Propolis from the central valley was more effective as antibacterial than those from the coastal area or Andean slopes. The samples considered of interest (MIC ≤ 62.5 µg/mL showed effect on Escherichia coli, Pseudomonas sp., Yersinia enterocolitica and Salmonella enteritidis. Two new diarylheptanoids, a diterpene, the flavonoids pinocembrin and chrysin were isolated and elucidated by spectroscopic and spectrometric means. Some 29 compounds were dereplicated by HPLC-MS and tentatively identified, including nine flavones/flavonol derivatives, one flavanone, eight dihydroflavonols and nine phenyl-propanoids. Propolis from the Región del Maule showed large variation in antimicrobial effect, antioxidant activity and composition. So far the presence of diarylheptanoids in samples from the coastal area of central Chile can be considered as a marker of a new type of propolis.

  3. Antilisterial effects of antibacterial formulations containing essential oils, nisin, nitrite and organic acid salts in a sausage model.

    Science.gov (United States)

    Ghabraie, Mina; Vu, Khanh Dang; Huq, Tanzina; Khan, Avik; Lacroix, Monique

    2016-06-01

    This study was conducted to evaluate the effects of sixteen antibacterial formulations against Listeria monocytogenes in a sausage model using a standard experimental design with 4 independent factors at 2 levels (2(4)). Four independent factors consisted of nisin (12.5-25 ppm), nitrite (100-200 ppm) and organic acid salts (1.55-3.1 %) and the mixture of Chinese cinnamon and Cinnamon bark Essential Oils (EOs) (0.025-0.05 %). Based on the analysis, utilization of low (0.025 %) or high concentration (0.05 %) of EOs in combination with low concentration of nitrite (100 ppm), organic acid salts (1.55 %), and nisin (12.5 ppm) could reduce respectively 1.5 or 2.6 log CFU/g of L. monocytogenes in sausage at day 7 of storage as compared to the control. A predictive equation was created to predict the growth of L. monocytogenes in sausage. The sensory evaluation was then performed on selected optimized formulations in cooked meat (both pork and beef sausages) with a trained jury consisting of 35 individuals, demonstrated the selected antimicrobial formulations were organoleptically acceptable. The results revealed an important role of hurdle technology to control L. monocytogenes in meat product.

  4. The effect of visible-light intensity on shape evolution and antibacterial properties of triangular silver nanostructures

    Science.gov (United States)

    Ashkarran, Ali Akbar

    2016-08-01

    Triangular silver nanostructures represent a novel class of nanomaterials with tunable surface plasmon resonance (SPR). By controlling the size and geometry of these structures, their SPR peaks could be tuned from the visible to the near-infrared region with numerous applications in optoelectronic, sensors, nanomedicine and specially cancer diagnosis and treatment. In this study, triangular silver nanostructures were prepared by photoinducing of spherical silver nanoparticles (NPs) with an average diameter of 10 nm. Transmission electron microscopy (TEM) and ultra violet visible (UV-Vis) spectroscopy were used to characterize silver triangles. We have found that uniform triangular silver nanostructures can be obtained using an appropriate visible-light illumination to the primary spherical silver NPs. TEM images indicated that formation of triangular structures depends on the intensity of light source. The effect of intensity of visible-light source on the geometry and size distribution of silver triangles was investigated. It was found that formation of triangular structures in addition to their size and shape evolution strongly depends on the intensity of the light illumination. Furthermore, a comparative study on the antibacterial activities of silver triangles of different sizes reveals that silver triangles experience a size-dependent interaction with the gram-negative Escherichia coli bacteria.

  5. Synthesis, structural characterization of nano ZnTiO3 ceramic: An effective azo dye adsorbent and antibacterial agent

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    R.S. Raveendra

    2014-12-01

    Full Text Available Nanocrystalline meta-zinc titanate (ZnTiO3 ceramic was prepared using a self-propagating solution combustion synthesis (SCS for the first time using urea as fuel. The product was calcined at 800 °C for 2 h to improve the crystallinity. Powder X-ray diffraction (PXRD, Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, energy-dispersive X-ray spectroscopy (EDAX, high resolution transmission electron microscopy (HR-TEM and UV–vis absorption spectroscopy were used to characterize the final product. PXRD results show that the ilmenite type rhombohedral structure was formed when the sample was calcined at 800 °C for 2 h. Adsorption experiments were performed with cationic malachite green (MG dye. ∼96% dye was adsorbed onto nanocrystalline ZnTiO3 ceramic at pH 9 for 30 min of the contact time. The optimum adsorbent dose was found to be 0.45 g/L of dye. Langmuir–Hinshelwood model was used to study adsorption kinetics and first order kinetic model best describes the MG adsorption on ZnTiO3. Antibacterial activity was investigated against gram negative Klebsiella aerogenes, Pseudomonas desmolyticum, Escherichia coli, and gram positive Staphylococcus aureus bacteria by agar well diffusion method. Nanocrystalline ZnTiO3 ceramic showed significant effect on all the four bacterial strains at the concentration of 1000 and 1500 μg per well.

  6. Eucalyptus oil nanoemulsion-impregnated chitosan film: antibacterial effects against a clinical pathogen, Staphylococcus aureus, in vitro

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    Sugumar S

    2015-10-01

    Full Text Available Saranya Sugumar, Amitava Mukherjee, Natarajan Chandrasekaran Centre for Nanobiotechnology, VIT University, Vellore, India Abstract: Eucalyptus oil (Eucalyptus globulus nanoemulsion was formulated using low- and high-energy emulsification methods. Development of nanoemulsion was optimized for system parameters such as emulsifier type, emulsifier concentration, and emulsification methods to obtain a lower droplet size with greater stability. The minimized droplet diameter was achieved using the high-energy method of ultrasonication. Tween 80 was more effective in reducing droplet size and emulsion appearance when compared to Tween 20. Stable nanoemulsion was formulated with Tween 80 as a surfactant, and the particle size was found to be 9.4 nm (1:2 v/v. The eucalyptus oil nanoemulsion was impregnated into chitosan (1% as a biopolymer in varying concentrations. Further, the film was characterized by moisture content, microscopic study, X-ray diffraction, and Fourier transform infrared spectroscopy. Also, the film with and without nanoemulsion was evaluated against Staphylococcus aureus. The nanoemulsion-impregnated chitosan film showed higher antibacterial activity than chitosan film. These results support the inclusion of nanoemulsion-impregnated chitosan film in wound management studies. Keywords: essential oil, emulsion, biopolymer, impregnation, thin film, wound isolate

  7. The Antibacterial Activity of Coriolus versicolor Methanol Extract and Its Effect on Ultrastructural Changes of Staphylococcus aureus and Salmonella Enteritidis

    Science.gov (United States)

    Matijašević, Danka; Pantić, Milena; Rašković, Božidar; Pavlović, Vladimir; Duvnjak, Dunja; Sknepnek, Aleksandra; Nikšić, Miomir

    2016-01-01

    The antibacterial activity of methanol extract obtained from fruiting body of industrially grown basidiomycete Coriolus versicolor was examined. The Minimum Inhibitory Concentration (MIC) values against various bacteria ranged from 0.625 to 20 mg mL-1. C. versicolor expressed bactericidal activity against both Gram-positive and Gram-negative bacteria. The growth curves of Staphylococcus aureus and Salmonella enterica serovar Enteritidis, measured at 630 nm, and confirmed with macrodilution method showed that the obtained extract could inhibit the growth of tested bacteria. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the loss of 260-nm-absorbing material were used to examine the ultrastructural changes in bacteria induced by the extract. When S. aureus was exposed to the MIC of C. versicolor, elongated and malformed cells were observed by SEM, while S. Enteritidis treated cells appeared shorter and aggregated with ruptured cell walls. TEM revealed the formation of non-membrane-enclosed bodies and depleted inner content of S. aureus. Larger and irregular periplasmic space and deformed and scattered components of the cell envelope were observed in treated S. Enteritidis. The loss of 260-nm-absorbing material indicated that the disruptive action of the extract on cytoplasmic membrane was more pronounced in S. aureus than in S. Enteritidis treated cells. The UV and FTIR spectrophotometric analyses revealed diverse composition of C. versicolor extract and high content of total phenolics. Altogether, mushroom extracts could be used to develop nutraceuticals or drugs effective against pathogenic microorganisms. PMID:27540376

  8. The Effectiveness of Poly-(4-vinyl-N-hexylpyridiniumbromide as an Antibacterial Implant Coating: An In Vitro Study

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    L. Ringenberg

    2011-01-01

    Full Text Available The clinical success of osseointegrated dental implants depends on the strong attachment of the surrounding hard and soft tissues. Bacterial adhesion on implant surfaces can cause inflammatory reactions and may influence healing and long-term success of dental implants. Promising implant coatings should minimize bacterial adhesion, but allow epithelial and connective tissue attachment. Therefore, the present study has examined the bioactive effect of poly-(4-vinyl-N-hexylpyridiniumbromide regarding typical oral bacteria as well as cytotoxicitiy to human cells considering different methods of connecting polymers to silicate-containing surfaces. The results revealed that the application of putative antibacterial and biocompatible polymer in coating strategies is affected by a variety of parameters. Published findings regarding reduced bacterial adhesion could not be verified using oral pathogens whereas hexylated polymers seem problematic for strong adhesion of soft tissue. Concerning innovative coatings for dental implants basic aspects (surface roughness, thickness, alkylation, combination with other polymers have to be considered in further investigations.

  9. Chemical Analysis and Study of Phenolics, Antioxidant Activity, and Antibacterial Effect of the Wood and Bark of Maclura tinctoria (L. D. Don ex Steud.

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    K. C. Lamounier

    2012-01-01

    Full Text Available Maclura tinctoria (L. D. Don ex Steud. has one of the highest qualities among the coefficients for Brazilian woods (up to 9.6 and resistance rates equivalent to Indian teak (Tectona grandis. In this study, the macromolecular constituents and total phenols compounds as well as the antioxidant and antibacterial activities of this wood were evaluated. Total phenols and proanthocyanidin levels were higher in wood when compared with bark levels. The antioxidant activity of wood extracts (IC50 = 18.7 μg/mL was more effective than that of bark extracts (IC50 = 20.9 μg/mL. Wood and bark extracts revealed a high potential for inhibition of aerobic and anaerobic bacteria. The bark extracts were the most active (MIC from 20 to 60 μg/mL. Both antioxidant activity and high potential for bacteria inhibition turn these extracts promising for drug formulations, especially as antibacterial agent.

  10. Study on the effect of chitosan on antibacterial stability of Nisin%壳聚糖对Nisin抑菌稳定性的影响研究

    Institute of Scientific and Technical Information of China (English)

    曾清清; 张立彦; 刘启莲

    2012-01-01

    Abstract.The effect of chitosan on antibacterial stability of Nisin was investigated,and the protection mechanism of chitosan to the Nisin was also explored by infrared(IR) spectroscopy and differential scanning calorimetry(DSC). The results showed that chitosan could significantly improve the antibacterial stability of Nisin.This effect had some discrepancies with different temperature and pH values.The antibacterial stability of Nisin was the best when the concentration of chitosan was ]%.The IR spectra and DSC thermogram showed that the form of hydrogen bonds between chitosan and Nisin could stabilize the structure of Nisin and improve its thermal stability,thus antibacterial stability of Nisin got better.%研究了壳聚糖对乳酸链球菌肽(Nisin)抑菌稳定性的作用,并利用红外光谱仪和差式扫描量热仪(DSC)分析了壳聚糖对Nisin保护作用的机理。结果表明:壳聚糖可以显著提高Nisin的抑菌稳定性,在不同的温度及pH范围内,其保护效果有所差异;壳聚糖浓度在1%时效果最好;红外光谱和DSC图谱研究显示,壳聚糖能与Nisin形成氢键,稳定Nisin的空间结构,并能提高Nisin的热稳定性,从而改善了其抑菌稳定性。

  11. Effect of surface passivation on corrosion resistance and antibacterial properties of Cu-bearing 316L stainless steel

    Science.gov (United States)

    Zhao, Jinlong; Xu, Dake; Shahzad, M. Babar; Kang, Qiang; Sun, Ying; Sun, Ziqing; Zhang, Shuyuan; Ren, Ling; Yang, Chunguang; Yang, Ke

    2016-11-01

    The resistance for pitting corrosion, passive film stability and antibacterial performance of 316L-Cu SS passivated by nitric acid solution containing certain concentration of copper sulfate, were studied by electrochemical cyclic polarization, electrochemical impedance spectroscopy (EIS) and co-culture with bacteria. Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze the Cu2+ ions release from 316L-Cu SS surface. XPS analysis proved that the enrichment of CuO, Cr2O3 and Cr(OH)3 on the surface of specimen could simultaneously guarantee a better corrosion resistance and stable antibacterial properties. The biocompatibility evaluation determined by RTCA assay also indicated that the 316L-Cu SS after antibacterial passivation was completely biocompatible.

  12. Effect of vanadic anhydride and copper oxide on the development of hard porcelain composite and its antibacterial activity

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    Arpan Kool

    2014-09-01

    Full Text Available A mullite-reinforced porcelain composite with antibacterial properties has been developed using transition metal oxides by solid state sintering. The composite has been characterized in terms of mullite content, hardness, color and antibacterial properties. The physico-chemical properties of the porcelain were substantially increased in the presence of V2O5 and CuO. Well-crystallized needle shaped mullite of average length ∼ 3 μm was observed in the porcelain body at 1300 °C and 1500 °C after the addition of V2O5 and CuO. Vickers hardness of the composite increased 4.2 times for 2% V2O5 at 1500 °C. The porcelain composites showed satisfactory antibacterial activity on gram negative bacteria Escherichia coli with mortality rates of 45% and 22% for V2O5 and CuO doped porcelain respectively.

  13. The synergistic effects of CO2 laser treatment with calcium silicate cement of antibacterial, osteogenesis and cementogenesis efficacy

    Science.gov (United States)

    Hsu, T.-T.; Kao, C.-T.; Chen, Y.-W.; Huang, T.-H.; Yang, J.-J.; Shie, M.-Y.

    2015-05-01

    Calcium silicate-based material (CS) has been successfully used in dental clinical applications. Some researches show that the antibacterial effects of CO2 laser irradiation are highly efficient when bacteria are embedded in biofilm, due to a photo-thermal mechanism. The purpose of this study was to confirm the effects of CO2 laser irradiation on CS, with regard to both material characterization and human periodontal ligament cell (hPDLs) viability. CS was irradiated with a dental CO2 laser using directly mounted fiber optics in wound healing mode with a spot area of 0.25 cm2, and then stored in an incubator at 100% relative humidity and 37 °C for 1 d to set. The hPDLs cultured on CS were analyzed, along with their proliferation and odontogenic differentiation behaviors. The results indicate that the CO2 laser irradiation increased the amount of Ca and Si ions released from the CS, and regulated cell behavior. CO2 laser-irradiated CS promoted cementogenic differentiation of hPDLs, with the increased formation of mineralized nodules on the substrate’s surface. It also up-regulated the protein expression of multiple markers of cementogenic and the expression of cementum attachment protein. The current study provides new and important data about the effects of CO2 laser irradiation on CS. Taking cell functions into account, the Si concentration released from CS with laser irradiated may be lower than a critical value, and this information could lead to the development of new regenerative therapies for dentin and periodontal tissue.

  14. Antibacterial Effects of Major Compounds in Essential Oil from Bamboo Leaves%竹叶挥发油中主要化合物的抑菌作用

    Institute of Scientific and Technical Information of China (English)

    吕兆林; 林西; 郭弘璇; 秦娇; 侯智霞; 张柏林

    2012-01-01

    This paper reports the antibacterial effect of three major monomeric compounds (tricosane, cedrol and hexadecanoic acid) in the essential oil from bamboo leaves. Using agar diffusion method, the antibacterial action of these monomers and their mixtures were studied against different microorganisms: Gram-positive bacteria (Bacillus subtil&), Gram-negative bacteria (Escherichia coli, Pseudomonasfluorescens, Flavobacterium columnare) and yeast. The results showed that cedrol had the strongest antibacterial effect, followed by hexadecanoic acid. The antibacterial effect of combinations of the three monomers was stronger than that seen when they were separately tested. The antibacterial effect of tricosane when used in combination with cedrol was much better than that observed when it was used alone, but slightly lower than that of cedrol alone. Similarly, the antibacterial effect of tricosane was increased by combination with hexadecanoic acid, but was weaker than that of hexadecanoic acid. The antibacterial effect of a mixture of cedrol and hexadecanoic acid was higher than that observed when hexadecanoic acid was tested alone, but slightly lower than that of sole hexadecanoic acid treatment. The antioxidant effect of a mixture of the three monomers was higher than that seen when tricosane and hexadecanoic acid were tested alone, and also higher than that of combinations of two of them.%选取毛竹叶挥发油中含量相对较高的化合物,即正二十三碳烷、雪松脑和十六烷酸3种单体化合物,采用双层平板打孔法,研究不同质量浓度的3种单体及各单体的混合物溶液对革兰氏阳性菌(枯草芽孢杆菌)、革兰氏阴性菌(大肠杆菌、假单胞杆菌、黄杆菌)及酵母菌等菌株的抑菌功效。结果表明:雪松脑具有较强的抑菌功效,十六烷酸次之;3种单体的混合溶液亦具有较好的抑菌功效,且普遍高于单体单独作用的效果:正二十三碳

  15. Antibacterial effects of gum kondagogu reduced/stabilized silver nanoparticles in combination with various antibiotics: a mechanistic approach

    Science.gov (United States)

    Rastogi, Lori; Kora, Aruna Jyothi; Sashidhar, R. B.

    2015-06-01

    Gum kondagogu reduced/stabilized silver nanoparticles (GK-AgNPs) were evaluated for their increased antibacterial and antibiofilm activities in combination with various antibiotics (ciprofloxacin, streptomycin and gentamicin) against Gram-positive ( Staphylococcus aureus 25923, Staphylococcus aureus 49834) and Gram-negative ( Escherichia coli 25922, Pseudomonas aeruginosa 27853) bacteria. The micro-broth dilution assay suggested an enhanced antibacterial activity of GK-AgNPs in combination with ciprofloxacin and aminoglycosides (streptomycin and gentamicin) against tested strains. Though the antibacterial activity of GK-AgNPs was found to increase significantly in the presence of antibiotics, the % enhancement was found to depend on both types of antibiotic and bacterial strain. It was also found that GK-AgNPs (1 µg/mL) in combination with various antibiotics at sub-MIC concentrations could inhibit 70 % of the bacterial biofilm formation as compared to respective controls. The enhanced antibacterial activity was due to the increased production of intracellular reactive oxygen species in bacteria when treated with a combination of GK-AgNPs and streptomycin as compared to individual treatment. The increased oxidative stress led to increased membrane damage as assessed by live/dead assay and higher levels of potassium ion release from the cells treated with both silver nanoparticles and streptomycin. The results suggested that the combination of antibiotics with GK-AgNPs has an enhanced antibacterial action. Further, the GK-AgNPs were found to be biocompatible up to a concentration of 2.5 µg/mL as assessed with MTT assay on HeLa cell line. The results suggest that GK-AgNPs could potentially be used as in vivo antibacterial agent in combination with antibiotics to overcome the problem of antibiotic resistance.

  16. Antibacterial Properties and Effects of Fruit Chilling and Extract Storage on Antioxidant Activity, Total Phenolic and Anthocyanin Content of Four Date Palm (Phoenix dactylifera Cultivars

    Directory of Open Access Journals (Sweden)

    Muhammad Azizan Samad

    2016-03-01

    Full Text Available Phoenix dactylifera or date palm fruits are reported to contain natural compounds that exhibit antioxidant and antibacterial properties. This research aimed to study the effect of fruit chilling at 4 °C for 8 weeks, extract storage at −20 °C for 5 weeks, and extraction solvents (methanol or acetone on total phenolic content (TPC, antioxidant activity and antibacterial properties of Saudi Arabian P. dactylifera cv Mabroom, Safawi and Ajwa, as well as Iranian P. dactylifera cv Mariami. The storage stability of total anthocyanin content (TAC was also evaluated, before and after storing the extracts at −20 °C and 4 °C respectively, for 5 weeks. Mariami had the highest TAC (3.18 ± 1.40 mg cyd 3-glu/100 g DW while Mabroom had the lowest TAC (0.54 ± 0.15 mg cyd 3-glu/100 g DW. The TAC of all extracts increased after storage. The chilling of date palm fruits for 8 weeks prior to solvent extraction elevated the TPC of all date fruit extracts, except for methanolic extracts of Mabroom and Mariami. All IC50 values of all cultivars decreased after the fruit chilling treatment. Methanol was a better solvent compared to acetone for the extraction of phenolic compounds in dates. The TPC of all cultivars extracts decreased after 5 weeks of extract storage. IC50 values of all cultivars extracts increased after extract storage except for the methanolic extracts of Safawi and Ajwa. Different cultivars exhibited different antibacterial properties. Only the methanolic extract of Ajwa exhibited antibacterial activity against all four bacteria tested: Staphylococcus aureus, Bacillus cereus, Serratia marcescens and Escherichia coli. These results could be useful to the nutraceutical and pharmaceutical industries in the development of natural compound-based products.

  17. Antibacterial Properties and Effects of Fruit Chilling and Extract Storage on Antioxidant Activity, Total Phenolic and Anthocyanin Content of Four Date Palm (Phoenix dactylifera) Cultivars.

    Science.gov (United States)

    Samad, Muhammad Azizan; Hashim, Siti Hajar; Simarani, Khanom; Yaacob, Jamilah Syafawati

    2016-03-26

    Phoenix dactylifera or date palm fruits are reported to contain natural compounds that exhibit antioxidant and antibacterial properties. This research aimed to study the effect of fruit chilling at 4 °C for 8 weeks, extract storage at -20 °C for 5 weeks, and extraction solvents (methanol or acetone) on total phenolic content (TPC), antioxidant activity and antibacterial properties of Saudi Arabian P. dactylifera cv Mabroom, Safawi and Ajwa, as well as Iranian P. dactylifera cv Mariami. The storage stability of total anthocyanin content (TAC) was also evaluated, before and after storing the extracts at -20 °C and 4 °C respectively, for 5 weeks. Mariami had the highest TAC (3.18 ± 1.40 mg cyd 3-glu/100 g DW) while Mabroom had the lowest TAC (0.54 ± 0.15 mg cyd 3-glu/100 g DW). The TAC of all extracts increased after storage. The chilling of date palm fruits for 8 weeks prior to solvent extraction elevated the TPC of all date fruit extracts, except for methanolic extracts of Mabroom and Mariami. All IC50 values of all cultivars decreased after the fruit chilling treatment. Methanol was a better solvent compared to acetone for the extraction of phenolic compounds in dates. The TPC of all cultivars extracts decreased after 5 weeks of extract storage. IC50 values of all cultivars extracts increased after extract storage except for the methanolic extracts of Safawi and Ajwa. Different cultivars exhibited different antibacterial properties. Only the methanolic extract of Ajwa exhibited antibacterial activity against all four bacteria tested: Staphylococcus aureus, Bacillus cereus, Serratia marcescens and Escherichia coli. These results could be useful to the nutraceutical and pharmaceutical industries in the development of natural compound-based products.

  18. Effect of organic fertilizers prepared from organic waste materials on the production of antibacterial volatile organic compounds by two biocontrol Bacillus amyloliquefaciens strains.

    Science.gov (United States)

    Raza, Waseem; Wei, Zhong; Ling, Ning; Huang, Qiwei; Shen, Qirong

    2016-06-10

    Three organic fertilizers made of different animal and plant waste materials (BOFs) were evaluated for their effects on the production of antibacterial volatile organic compounds (VOCs) by two Bacillus amyloliquefaciens strains SQR-9 and T-5 against the tomato wilt pathogen Ralstonia solanacearum (RS). Both strains could produce VOCs that inhibited the growth and virulence traits of RS; however, in the presence of BOFs, the production of antibacterial VOCs was significantly increased. The maximum inhibition of growth and virulence traits of RS by VOCs of T-5 and SQR-9 was determined at 1.5% BOF2 and 2% BOF3, respectively. In case of strain T-5, 2-nonanone, nonanal, xylene, benzothiazole, and butylated hydroxy toluene and in case of strain SQR-9, 2-nonanone, nonanal, xylene and 2-undecanone were the main antibacterial VOCs whose production was increased in the presence of BOFs. The results of this study reveal another significance of using organic fertilizers to improve the antagonistic activity of biocontrol agents against phytopathogens.

  19. The effects of Mg incorporation and annealing temperature on the physicochemical properties and antibacterial activity against {\\it Listeria monocytogenes} of ZnO nanoparticles

    Indian Academy of Sciences (India)

    NIMA SHADAN; ALI ABDOLAHZADEH ZIABARI; RAFIEH MERAAT; KAMYAR MAZLOUM JALALI

    2017-02-01

    In this paper, Mg-doped ZnO nanoparticles were synthesized by the facile sol–gel method. The crystalline structure, characteristic absorption bands and morphology of the obtained Mg-doped ZnO nanoparticles were studied by XRD, FTIR and TEM. The thermal degradation behaviour of the samples was investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG). The effect of Mg concentrations and annealing temperatures on the antibacterial properties of the obtained nanoparticles was investigated in detail.The results indicated that doping Mg ions into ZnO lattice could enhance its antibacterial activity. Antibacterial assay demonstrated that Mg-doped ZnO with 7% Mg content annealed at 400◦C had the strongest antibacterialactivity against {\\it Listeria monocytogenes} (98.7%). This study indicated that the inhibition rate of ZnO nanoparticles increased with the formation of granular structure and the decrease of ZnO size due to the doping of Mg ions into the ZnO lattice.

  20. Antibacterial Effects of Gold Nanoparticles on Multi-sdrug Resistant Klebsiella Pneumoniae and Escherichia Coli and Its Effect on the Liver of Balb/C mice

    Directory of Open Access Journals (Sweden)

    L Rahimzade Torabi

    2016-01-01

    Full Text Available Introduction: The gold nanoparticles as other nanoparticles have catalytic, magnetic, optical, and biological (antimicrobial properties. On the other hand, resistance to antibiotics is one of the greatest public health problems posed in the world. Therefore, the present study aimed to investigate the antibacterial effects of gold nanoparticles on multi-drug resistant klebsiella pneumoniae as well as escherichia coli and its effect on the liver of balb/c mice. Methods: In this study, multi-drug resistant Klebsiella pneumoniae and Escherichia coli bacteria clinical samples were utilized that were isolated from several hospitals in Isfahan and then the toxic effects of nanoparticles were investigated on the Balb / C mice. Colloidal gold nanoparticles were also applied with spherical shape and a concentration of 200 ppm in size of 10 nm, using two wells and disk agar diffusion method. Antibacterial properties of the nanoparticles were evaluated within 1-3 days with 37 ˚c temperature, and diameter of inhibitory zone of growth was measured every day. Tissue and liver enzymes of the mice were examined, as well. Results: The greatest diameter of inhibitory zone was detected in multi drug resistant E. coli. Most of the MIC and MBC were found in multi-drug resistant Klebsiella pneumoniae bacteria .Gold nanoparticles did not reveal any significant changes on the weight, liver enzymes and liver tissue of Balb / C mice after one month. Conclusion: As the findings of the current study revealed, inhibitory effect of gold nanoparticles was observed on the axamined microorganism. Although the laboratories findings are promising, more studies should be conducted in regard with therapeutic standardization.

  1. A comparative evaluation of antibacterial effectiveness of sodium hypochlorite, Curcuma longa, and Camellia sinensis as irrigating solutions on isolated anaerobic bacteria from infected primary teeth

    Directory of Open Access Journals (Sweden)

    Neha Shashikant Dhariwal

    2016-01-01

    Full Text Available Context: In endodontics, most of the commercial intra-canal medicaments have cytotoxic reactions and because of their inability to eliminate bacteria from dentinal tubules, recent medicine has turned its attention to the usage of biologic medication prepared from natural plants. The literature to testify the efficacy of natural alternatives in primary teeth is meagre and its effects as irrigating solutions need to be evaluated. Aim: To evaluate the antibacterial effectiveness of sodium hypochlorite, ethanolic extracts of Curcuma longa (turmeric and Camellia sinensis (green tea as irrigating solutions against the anaerobic bacteria isolated from the root canals of infected primary teeth. Materials and Methods: Thirty patients were selected based on the selected inclusion and exclusion criteria. Preoperative radiographs were taken. Rubber dam isolation and working length estimation were done, following which thirty samples were taken from the root canals of infected primary teeth using sterile absorbent paper points and transferred to tubes containing thioglycolate transport medium. The bacteria were then isolated using standard microbiological protocols and were subjected to antibiotic sensitivity testing using the three test irrigants. Statistical Analysis: SPSS 18 software using Chi-square test was used for statistical analysis. Results: The most commonly isolated bacteria included Porphyromonas sp., Bacteroides fragilis, Peptostreptococcus, and Staphylococcus aureus. Sodium hypochlorite and C. longa (turmeric showed good antibacterial effect and were effective against most of the isolated bacteria. There was statistically significant difference in the antibacterial effect among the three tested groups (P < 0.001. The least effective was C. sinensis (green tea. Conclusion: The infected primary teeth almost always present with a polymicrobial structure with a wide variety of anaerobic bacteria. The chemo-mechanical preparation plays an important

  2. Comparison of Antibacterial Effects of ZnO and CuO Nanoparticles Coated Brackets against Streptococcus Mutans

    Directory of Open Access Journals (Sweden)

    Baratali Ramazanzadeh

    2015-09-01

    Full Text Available Statement of the Problem: During the orthodontic treatment, microbial plaques may accumulate around the brackets and cause caries, especially in high-risk patients. Finding ways to eliminate this microbial plaque seems to be essential. Purpose: The aim of this study was to compare the antibacterial effects of nano copper oxide (CuO and nano zinc oxide (ZnO coated brackets against Streptococcus mutans (S.mutans in order to decrease the risk of caries around the orthodontic brackets during the treatment. Materials and Method: Sixty brackets were coated with nanoparticles of ZnO (n=20, CuO (n=20 and CuO-ZnO (n=20. Twelve uncoated brackets constituted the control group. The brackets were bonded to the crowns of extracted premolars, sterilized and prepared for antimicrobial tests (S.mutans ATCC35668. The samples taken after 0, 2, 4, 6 and 24 hours were cultured on agar plates. Colonies were counted 24 hours after incubation. One-way ANOVA and Tukey tests were used for statistical analysis. Results: In CuO and CuO-ZnO coated brackets, no colony growth was seen after two hours. Between 0-6 hours, the mean colony counts were not significantly different between the ZnO and the control group (p>0.05. During 6-24 hours, the growth of S.mutans was significantly reduced by ZnO nanoparticles in comparison with the control group (p< 0.001. However, these bacteria were not totally eliminated. Conclusion: CuO and ZnO-CuO nanoparticles coated brackets have better antimicrobial effect on S.mutans than ZnO coated brackets.

  3. Milestones in the discovery of antiviral agents: nucleosides and nucleotides

    Directory of Open Access Journals (Sweden)

    Erik de Clercq

    2012-12-01

    Full Text Available In this review article, a number of milestones in the antiviral research field on nucleosides and nucleotides are reviewed in which the author played a significant part, especially in the initial stages of their development. Highlighted are the amino acyl esters of acyclovir, particularly valacyclovir (VACV, brivudin (BVDU and the valine ester of Cf1743 (FV-100, the 2′,3′-dideoxynucleosides (nucleoside reverse transcriptase inhibitors, NRTIs, the acyclic nucleoside phosphonates (S-HPMPA, (S-HPMPC (cidofovir and alkoxyalkyl esters thereof (HDP-, ODE-CDV, adefovir and adefovir dipivoxil, tenofovir and tenofovir disoproxil fumarate (TDF, combinations containing TDF and emtricitabine, i.e., Truvada®, Atripla®, Complera®/Eviplera® and the Quad pill, and the phosphonoamidate derivatives GS-7340, GS-9131, GS-9191 and GS-9219.

  4. Synthesis and Antiviral Activity of 3-Aminoindole Nucleosides of 2-Acetamido-2-deoxy-D-glucose

    Energy Technology Data Exchange (ETDEWEB)

    Abdelrahman, Adel A. H.; Elessawy, Farag A.; Barakat, Yousif A. [Menoufia Univ., Shebin El-Koam (Egypt); Ellatif, Mona M. Abd [The British Univ. in Egypt, Cairo (Egypt)

    2012-10-15

    A new method for the construction of 3-aminoindole nucleosides of 2-acetamido-2-deoxy-D-glucose based is presented. Nitration and acetylation of the indole nucleosides by acetic anhydride-nitric acid mixture followed by reduction using silver catalyst (SNSM) impregnated on silica gel, afforded the corresponding amino indole nucleosides. The nucleosides were tested for antiviral activity against hepatitis B virus (HBV) to show different degrees of antiviral activities or inhibitory actions.

  5. Study on the in vitro antibacterial effects of rutin%芸香苷的体外抑菌作用

    Institute of Scientific and Technical Information of China (English)

    姚萍; 葛新; 董小青; 陈虹

    2013-01-01

    Objective:To study the antibacterial effects of rutin on pathogenic strains and provide theoretical data for application. Methods: Rutin was extracted by alkali - solution and acid - isolation from the barks of Sophora japonica Linn, then further purified. The broth microdilution was used to measure the minimal inhibitory concentration (MIC) for the tested strains. The skin simulation and antibacterial effects on the natural bacteria of skin were observed. Results: The purified extract contained 95.2% of rutin. The MICs of rutin solution for Escherichia coli, Shigella flexneri, Proteus mirabilis, Staphylococcus epidermidis and Staphylococcus aureus were 0.5 g/L, 0.5 g/L, 1.0 g/L, 0.25 g/L, and 0.25 g/L, respectively. 2.0 g/L of rutin showed no simulations to the rat skin, and reduced the natural bacteria of forearm skin of volunteers from 244 cfu/cm2 to 16 cfu/cm2 after smeared for 2 min. Conclusion: Rutin had obvious inhibitory effects on bacterial vegetative form, especially on Gram positive bacteria.%目的:观察芸香苷对常见致病菌体外抑制效果,为实际应用研究提供依据.方法:采用碱溶酸沉法从槐树皮中提取芸香苷并进一步纯化,采用微量稀释法对精制芸香苷进行实验室抑菌试验,并检测其皮肤刺激性与皮肤抗菌效果.结果:精制芸香苷有效成分含量95.2%,其溶液对大肠杆菌和福氏志贺菌MIC值为0.5 g/L,对奇异变形杆菌MIC值为1.0 g/L,对金黄色葡萄球菌和表皮葡萄球菌的MIC值为0.25 g/L.2.0 g/L精制芸香苷溶液对大鼠皮肤无刺激性,涂擦人体前臂皮肤作用2min,可使皮肤上自然菌由处理前的244 cfu/cm2降低到16 cfu/cm2.结论:芸香苷对细菌繁殖体有明显抑菌作用,对革兰阳性菌抑制作用强于革兰阴性菌.

  6. Nucleoside H-boranophosphonates: synthesis and properties of a new class of nucleotide analogs.

    Science.gov (United States)

    Higashida, Renpei; Kawanaka, Toshihide; Oka, Natsuhisa; Wada, Takeshi

    2007-01-01

    Nucleoside H-boranophosphonates were synthesized via the condensation reactions of appropriately protected nucleosides with monopyridinium H-boranophosphonate. The condensation reactions gave only the mono-esterified products under the optimized conditions without formation of di-esterified byproducts. Deprotection of the condensation products was achieved under basic conditions to afford the fully-deprotected nucleoside H-boranophosphonates in excellent yields.

  7. Enantiomeric Synthesis of Novel Apiosyl Nucleosides as Potential Antiviral Agents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ai Hong; Hong, Joon Hee [Chosun University, Gwangju (Korea, Republic of)

    2004-02-15

    A series of 2',3'-dideoxy-3'-fluoro-D-apiosyl nucleosides 15, 16, 17 and 18 were synthesized enantiomerically with L-Gulonic-{gamma}-lactone as the starting material. The reduction of butenolide 1 with DIBAL-H followed by the Luche procedure afforded the allylic alcohol 2. Ozonolysis and the reduction of compound 4 induced the cyclized lactol, which was acetylated to give the acetate 7. Condensation of the acetate 7 with silylated pyrimidine (N{sup 4}-benzoyl cytosine) and a purine base (6-chloropurine) under Vorbruggen conditions and deblocking afforded a series of fluorinated apiosyl nucleosides

  8. Synthesis of Novel 1,3-Dioxolane Nucleoside Analogues

    Institute of Scientific and Technical Information of China (English)

    蔡冬梅; 林昆华; 李明宗; 温集武; 李鸿艳; 尤田耙

    2004-01-01

    Novel 1,3-dioxolane C-nucleoside analogues of tiazofurin 2-(2-hydroxymethyl-1,3-dioxolan-4-yl)-1,3-thiazole-4-carboxamide as well as N-nucleoside analogues of substituted imidazoles 1-(2-hydroxymethyl-1,3-dioxolan-4-yl)-4-nitroimidazole and 1-(2-hydroxymethyl-1,3-dioxolan-4-yl)-4,5-dicyanoimidazole were synthesized frommethyl acrylate through a multistep procedure. Their structures were confirmed by IR, 1H NMR, 13C NMR spectra and elemental analysis.

  9. Synthesis of some novel hydrazono acyclic nucleoside analogues

    Directory of Open Access Journals (Sweden)

    Mohammad N. Soltani Rad

    2010-05-01

    Full Text Available The syntheses of novel hydrazono acyclic nucleosides similar to miconazole scaffolds are described. In this series of acyclic nucleosides, pyrimidine as well as purine and other azole derivatives replaced the imidazole function in miconazole and the ether group was replaced with a hydrazone moiety using phenylhydrazine. To interpret the dominant formation of (E-hydrazone derivatives rather than (Z-isomers, PM3 semiempirical quantum mechanic calculations were carried out which indicated that the (E-isomers had the lower heats of formation.

  10. Nucleoside triphosphate synthesis catalysed by adenylate kinase is ADP dependent

    DEFF Research Database (Denmark)

    Willemoës, Martin; Kilstrup, Mogens

    2005-01-01

    Adenylate kinase (Adk) that catalyses the synthesis of ADP from ATP and AMP has also been shown to perform an ATP dependent phosphorylation of ribo- and deoxynucleoside diphosphates to their corresponding nucleoside triphosphate; ATP+(d)NDPADP+(d)NTP. This reaction, suggested to occur by the tran......Adenylate kinase (Adk) that catalyses the synthesis of ADP from ATP and AMP has also been shown to perform an ATP dependent phosphorylation of ribo- and deoxynucleoside diphosphates to their corresponding nucleoside triphosphate; ATP+(d)NDPADP+(d)NTP. This reaction, suggested to occur...

  11. Cost-effectiveness of pre-referral antimalarial, antibacterial, and combined rectal formulations for severe febrile illness.

    OpenAIRE

    Buchanan, J.; Mihaylova, B.; Gray, A; White, N

    2010-01-01

    BACKGROUND: Malaria and bacterial infections account for most infectious disease deaths in developing countries. Prompt treatment saves lives, but rapid deterioration often prevents the use of oral therapies; delays in reaching health facilities providing parenteral interventions are common. Rapidly and reliably absorbed antimalarial/antibacterial rectal formulations used in the community could prevent deaths and disabilities. Rectal antimalarial treatments are currently available; rectal ant...

  12. Effect of bile on nisin-mediated antibacterial activity and the expression of nisin genes of Lactococcus lactis W8.

    Science.gov (United States)

    Mitra, Suranjita; Mukhopadhyay, Bidhan Chandra; Chakrabartty, Pran Krishna; Biswas, Swadesh Ranjan

    2013-12-01

    The capability of Lactococcus lactis to produce nisin in the presence of bile in the intestinal environment remains an intriguing question. The aim of this study was to determine the effects of bile on production of nisin and the mRNA expression of nisin genes of L. lactis W8. The strain L. lactis W8 was grown on glucose in the absence and presence of bile (0.005-0.08 %) and the antibacterial activities of culture supernatants were determined. In culture with 0.035 % bile, the nisin activity was significantly reduced (400 AU/mL) within 5 h compared to that in the control without bile (2000 AU/mL), while growth of the cells was only slightly affected. In the presence of 0.07 % bile no nisin activity of the strain was manifested. Consistent with these results, mRNA expression of nisin-biosynthetic genes nisZ, nisRK, nisI, and nisF was down-regulated by 7.5-, 2.5-, 1.7-, and 6.0-fold, respectively in cells grown in the presence of bile (0.07 %) as compared to control culture without bile. The present study suggested that bile inhibited transcription of nisin genes. Nisin-production in intestine by orally administered L. lactis, thus, does not occur since complete inhibition of nisin-production by bile is observed at a concentration much lower than the physiological concentration (0.3 %) of bile present in the human intestine. The molecular mechanism underlying the bile-mediated inhibition of nisin genes remains to be elucidated. This is the first report on bile-mediated inhibition of nisin genes.

  13. Survey of Antibacterial Effect of Methanolic Extract of Fulgensia fulgens through in Vitro and in Vivo Conditions

    Directory of Open Access Journals (Sweden)

    tahereh valdbeigi

    2016-06-01

    Full Text Available Introduction: Daily increasing of bacteria resistance (specially Staphylococcus aureus to various antibiotics in particular penicillin and methicillin has always led the scientists to look for new medicines. Materials and methods: 600 g of Fulgensia fulgens was collected from KaneGonbad mountains in Ilam province, the methanol extract was prepared by soxhle. In vitro antimicrobial activity of the extract against two gram-positive bacteria (S. aureus and Entrococcus faecalis and two gram-negative bacteria (Pseudomonas aeruginosa and Escherchia coli was tested by the use of disc diffusion method and microdilution (with determination of MIC and MBC. Wound was made on the dorsal surface of therat and wound infections caused by S.aureus for determination of in vivo antibacterial effect. Than rats were randomly divided into three groups; control, treated with tetracycline ointment and treated with 10% ointment of F. fulgens extract. Finally, wound areas wear measured on days 3, 5, 7, 9 and 11. Results: Average inhibitory zone diameter of methanolic F. fulgens extract against S. aureus ranged between 11.21 mm to 33.01 mm. According to the wound area on 11th day, it could be concluded that there was a statistically significant difference between the control group (0.63 cm2 and two treatment groups (0 (p<0.05. There was no significant difference between a group treated with tetracycline ointment and a group treated with 10% ointment of extract. Discussion and conclusion: According to the results, the methanol extract of F. fulgens in the treatment of infections as S. aureus can be replaced by chemical antibiotics.

  14. Antibacterial activity of epidural infusions.

    Science.gov (United States)

    Coghlan, M W; Davies, M J; Hoyt, C; Joyce, L; Kilner, R; Waters, M J

    2009-01-01

    The incidence of epidural abscess following epidural catheterisation appears to be increasing, being recently reported as one in 1000 among surgical patients. This study was designed to investigate the antibacterial activity of various local anaesthetics and additives, used in epidural infusions, against a range of micro-organisms associated with epidural abscess. The aim was to determine which, if any, epidural infusion solution has the greatest antibacterial activity. Bupivacaine, ropivacaine and levobupivacaine crystals were dissolved and added to Mueller-Hinton Agar in concentrations of 0.06%, 0.125%, 0.2%, 0.25%, 0.5% and 1%. Fentanyl, adrenaline and clonidine were also mixed with agar in isolation and in combination with the local anaesthetics. Using a reference agar dilution method, the minimum inhibitory concentrations were determined for a range of bacteria. Bupivacaine showed antibacterial activity against Staphylococcus aureus, Enterococcus faecalis and Escherichia coli with minimum inhibitory concentrations between 0.125% and 0.25%. It did not inhibit the growth of Pseudomonas aeruginosa at any of the concentrations tested. Levobupivacaine and ropivacaine showed no activity against Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa, even at the highest concentrations tested, and minimal activity against Escherichia coli (minimum inhibitory concentrations 0.5% and 1% respectively). The presence of fentanyl, adrenaline and clonidine had no additional effect on the antibacterial activity of any of the local anaesthetic agents. The low concentrations of local anaesthetic usually used in epidural infusions have minimal antibacterial activity. While the clinical implications of this in vitro study are not known, consideration should be given to increasing the concentration of bupivacaine in an epidural infusion or to administering a daily bolus of 0.25% bupivacaine to reduce the risk of epidural bacterial growth.

  15. An in Vitro Study on the Antibacterial Effect of Ferula Assa-Foetida L. and Quercus Infectoria Olivier Extracts on Streptococcus Mutans and Streptococcus Sanguis

    Directory of Open Access Journals (Sweden)

    Fani

    2015-06-01

    Full Text Available Background From the ancient times, medicinal herbs have been regarded as efficient resources for the treatment of diseases. Among the diseases that can be treated by medicinal herbs, infectious diseases like oral ones are of notable importance. Objectives The aim of this study was to evaluate the antibacterial effects of Ferula assa-foetida L (F. assa-foetida L. and Quercus infectoria Olivier (Q. infectoria Olivier aqueous and ethanolic extracts on Streptococcus mutans (S. mutans and Streptococcus sanguis (S. sanguis. Materials and Methods The studied plants were F. assa-foetida L. and Q infectoria Olivier. Their extracts with different concentrations of 100, 50, 25, 12.5, 6.25, and 3.125 mg/mL were prepared in culture medium, with well diffusion method, and, for control, their antibacterial effects were compared with chlorhexidine. For each extract, the antibacterial ability was determined based on the created inhibition zone diameter in the microbial culture medium. Results The aqueous and ethanolic extract of F. assa-foetida L. lacked the inhibitory effect against the growth of S. mutans and S. sanguis bacteria. There was a significant difference among the inhibitory zones created by dissimilar concentrations of Q. infectoria (P = 0.025. Also, the aqueous and ethanolic extracts’ minimum inhibitory concentration (MIC for S. mutans bacterium was calculated to be 12.5 mg/mL, while its value for S. sanguis bacterium was 6.25 mg/mL. Conclusions The results of our study, regarding the observed effects based on differences in concentrations, suggest that further and more comprehensive studies should be undertaken to determine the appropriate concentration for obtaining the effect of the extract of F. assa-foetida L. and Q infectoria Olivier on S. mutans and S. sanguis.

  16. Microbiological analysis and antibacterial effects of the indigenous fermented Puer tea

    NARCIS (Netherlands)

    Mo, H.Z.; Xu, X.Q.; Yan, M.C.; Yang Zhu, Yang

    2005-01-01

    Microbiological analysis was done on samples from an indigenously fermented tea - Puer. Microbial counting and identification revealed that Aspergillus niger was the dominating microorganism during the fermentation. Antimicrobial activity of fermentation samples showed inhibitory effect on several f

  17. Comparative antibacterial effectiveness of alcohol and herbal based commercially available hand antiseptics

    OpenAIRE

    K Vipin Jain; Sequeira Peter Simon; Jithesh Jain; S Supreetha; Mathew, M.J.; C B Sudeep

    2013-01-01

    Background: Human skin is a reservoir of numerous microorganisms. Even though hand washing with soap and water alone reduces the microbial load, the complementary uses of hand antiseptics enhance the antimicrobial effect. Aim: To compare the antimicrobial effectiveness of two commercially available hand antiseptics, routinely used in dental practice, after hand washing with antiseptic soap. Method: A clinical trial with cross over design was carried out on 12 health care workers (HCWs). The a...

  18. Vitamin C Pretreatment Enhances the Antibacterial Effect of Cold Atmospheric Plasma

    Science.gov (United States)

    Helgadóttir, Saga; Pandit, Santosh; Mokkapati, Venkata R. S. S.; Westerlund, Fredrik; Apell, Peter; Mijakovic, Ivan

    2017-01-01

    Bacterial biofilms are three-dimensional structures containing bacterial cells enveloped in a protective polymeric matrix, which renders them highly resistant to antibiotics and the human immune system. Therefore, the capacity to make biofilms is considered as a major virulence factor for pathogenic bacteria. Cold Atmospheric Plasma (CAP) is known to be quite efficient in eradicating planktonic bacteria, but its effectiveness against biofilms has not been thoroughly investigated. The goal of this study was to evaluate the effect of exposure of CAP against mature biofilm for different time intervals and to evaluate the effect of combined treatment with vitamin C. We demonstrate that CAP is not very effective against 48 h mature bacterial biofilms of several common opportunistic pathogens: Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa. However, if bacterial biofilms are pre-treated with vitamin C for 15 min before exposure to CAP, a significantly stronger bactericidal effect can be obtained. Vitamin C pretreatment enhances the bactericidal effect of cold plasma by reducing the viability from 10 to 2% in E. coli biofilm, 50 to 11% in P. aeruginosa, and 61 to 18% in S. epidermidis biofilm. Since it is not feasible to use extended CAP treatments in medical practice, we argue that the pre-treatment of infectious lesions with vitamin C prior to CAP exposure can be a viable route for efficient eradication of bacterial biofilms in many different applications. PMID:28275584

  19. Early Cellular Responses of Purine Nucleoside-mediated Protection of Hypoxia-induced Injuries of Neuronal PC12 Cells

    Directory of Open Access Journals (Sweden)

    Bettina Tomaselli

    2005-01-01

    Full Text Available Hypoxia in brain may lead to cell death by apoptosis and necrosis. In parallel adenosine, a powerful endogenous neuroprotectant is formed. We wanted to investigate the effect of adenosine and its purine nucleoside relatives, inosine and guanosine on early cellular responses to hypoxia. O2-sensitive neuronal PC12-cells were subjected to chemical hypoxia induced with rotenone, an inhibitor of mitochondrial complex I. Loss of viability after hypoxic insult was impressively rescued by adenosine, guanosine and inosine. PC12-cells mainly express the A2A adenosine receptor. Its inhibition with a specific antagonist (CSC induced cell death of PC12-cells, which could be salvaged by adenosine but not with guanosine or inosine. We have previously demonstrated the important role of mitogen activated protein kinases 1/2 (p42/44 MAPK in purine-mediated rescue. In this study we were interested in the involvement of protein kinases whose activities mediate these processes, including protein kinase A (PKA, phosphoinositide 3-kinase (PI3-K and protein kinase C-related kinases (PRK 1/2. Pharmacological inhibition of PKA and PI3-K increased hypoxia-induced toxicity and likewise also affected the rescue by purine nucleosides. Nerve growth factor (NGF and purine nucleosides induced an activation of PRK 1/2, which to our knowledge indicates for the first time that these kinases are potentially involved in purine nucleoside-mediated rescue of hypoxic neuronal cells. Results suggest that A2A receptor expressing cells are mainly dependent on the purine nucleoside adenosine for their rescue after hypoxic insult. In addition to PKA, PI3-K is an important effector molecule in A2A-mediated signaling and for the rescue of PC12-cells after hypoxic insult.

  20. In Vitro and in Silico Evaluation of Antibacterial Effect of Methanolic Extracts of Prangos Ferulacea on Single and Biofilm Structure of Streptococcus Mutans

    Directory of Open Access Journals (Sweden)

    M Nosrati

    2016-02-01

    Full Text Available Introduction: Investigating efficacy of natural products, especially plant materials in dental caries is of great significance. The present study aimed to evaluate in vitro and in silico anti bacterial effects of methanolic extracts of Prangos ferulacea on single and biofilm structure of streptococcus mutans. Methods: In this experimental study, after collecting the plants and determining their variety, they were air- dried and powdered. Then, the plants were extracted with methanol by the maceration method. In order to determine antibacterial activity as well as antibiofilm activity of the extracts, disk diffusion and micro titer assay were applied respectively. Regarding in silco analysis, the molecular docking was also preformed by iGemdock 2.1 software between Glucosyltransferases and 20 phytochemicals of the mentioned plants. SPSS software was utilized to statistically analyze the study data applying variance and Duncan’s multiple range test. Results: The results of the present study showed that studied extracts specially their roots extract up to250-3000 μg/ml have significant antibacterial effects against the single form of becteria, which lead to inhibition of biofilm structures formation of the tested strain, though it can not damage biofilm structures of the bacteria. In addition, MIC and MBC minimum values were determined in 250-1000 μg/ml and 500-3000 μg/ml spectera respectively. Then, silico analysis confirmed that studied phytochemical compounds, especially α-pinen, Pesoralen and Limonene revealed an appropriate interaction to Glucosyltransferases,  which could be regarded as an inhibitor for this enzyme. Conclusion: According to the results of the current study, P.ferulacea has significant antibacterial effects against single structure of S.mutans. However, it does not produce any significant effects on the biofilms structured from this bacteria.

  1. Evaluation of chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effects of Aloysia citrodora extract on colon cancer cell line using Real Time PCR and Flow-cytometry methods

    Directory of Open Access Journals (Sweden)

    Amir Mirzaie

    2016-06-01

    Full Text Available Background and aims: Aloysia citrodora belongs to the Verbenaceae family of plants, a well-known herbal medicine in Iran. The aim of the present study was to investigate the chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effect of A. citrodora extract against human colon cancer using real time PCR and flow cytometry methods. Materials and Methods: this experimental study was carried out in Islamic Azad University, East Tehran Branch, from March to September of 2014. At first, the A. citrodora chemical constituents were analyzed by GC/MS technique. In addition, antioxidant assay, antibacterial and anti-cancer effect was performed using DPPH, disk diffusion and MTT methods, respectively. Finally, the apoptosis gene (Bax and Bcl2 expression was performed by real time PCR and apoptotic effects was analyzed using Flow-cytometry technique. Results:  GC/MS analysis of A. citrodora extract was shown 37 major components and the most frequent component was belonged to Spathulenol (17.57% and Caryophyllene oxide (15.15%. The antioxidant activity of the extract was IC50=0.6 ±0.03. The maximum and minimum antibacterial effects of extract were belonged to Gram negative and Gram positive bacteria, respectively. Cytotoxic results revealed that the extract have IC50= 20.1± 0.78 mg/ml against colon cell line and Real Time PCR results showed the expression level of Bax and Bcl2 was increased and decreased respectively in colon cancer cell line (3.470 ± 0.72 (P<0.05, 0.43 ± 0.35 (P< 0.05. In addition, the flow-cytometry results indicated the 38.66 % apoptosis in colon cancer cell line. Conclusion: According to the results, it seems that A. citrodora extract has potential uses for pharmaceutical industries and it suggested that further studies were performed for A. citrodora pharmaceutical importance.

  2. Impact of curcumin supersaturation in antibacterial photodynamic therapy-effect of cyclodextrin type and amount

    DEFF Research Database (Denmark)

    Hegge, A.B.; Nielsen, T.T.; Larsen, Kim Lambertsen;

    2012-01-01

    Curcumin has been investigated as a potential photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). The phototoxic effect of curcumin is dependent on proper formulations of the compound because of the lipophilic nature of the molecule and the extremely low water solubility at physiol......Curcumin has been investigated as a potential photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). The phototoxic effect of curcumin is dependent on proper formulations of the compound because of the lipophilic nature of the molecule and the extremely low water solubility...... of E. coli. Depending on the curcumin preparation, the bacterial survival ranged from 0.01% to no significant effect after irradiation with blue light (29 J/cm2). Temporal stabilization of the supersaturated state is necessary in order to retain high and predictable photoreactivity of the PS. Further...

  3. Nanostructured Antibacterial Silver Deposited on Polypropylene Nonwovens

    Science.gov (United States)

    Hong-Bo, Wang; Jin-Yan, Wang; Qu-Fu, Wei; Jian-Han, Hong; Xiao-Yan, Zhao

    Nanostructured silver films were deposited on polypropylene (PP) nonwovens by RF magnetron sputter coating to obtain the antibacterial properties. Shake flask test was used to evaluate the antibacterial properties of the materials. Atomic force microscope (AFM) was utilized to observe the surface morphology. Energy-dispersive X-ray (EDX) was also employed to analyze the surface elemental compositions. The antibacterial results indicated that the prolonged deposition time led to a significant improvement in antibacterial effect, and sputtering power and argon pressure did not show obvious effect on antibacterial performance. It is believed that the total amount of silver ions released from the silver coating was increased as the deposition time increased. AFM images and quantitative analysis of EDX, respectively revealed that increase in deposition time led to the increased coverage of silver film and the increased silver weight percentage per unit surface, which provided evidences for the increased release rate of silver ions from the coating. Moreover, it was found that the optimum silver coating thickness was about 3 nm, taking antibacterial effect and cost of production into account.

  4. Anti-inflammatory effects of antibacterials on human bronchial epithelial cells

    Directory of Open Access Journals (Sweden)

    Hatz Rudolf

    2009-09-01

    Full Text Available Abstract Background Human Bronchial epithelial cells (hu-BEC have been claimed to play a significant role in the pathogenesis of chronic inflammatory airway diseases like COPD. In this context IL-8 and GM-CSF have been shown to be key cytokines. Some antibiotics which are routinely used to treat lower respiratory tract infections have been shown to exert additional immunomodulatory or anti-inflammatory effects. We investigated whether these effects can also be detected in hu-BEC. Methods Hu-BEC obtained from patients undergoing lung resections were transferred to air-liquid-interface (ALI culture. These cultures were incubated with cefuroxime (CXM, 10-62.5 mg/l, azithromycin (AZM, 0.1-1.5 mg/l, levofloxacin (LVX, 1-8 mg/l and moxifloxacin (MXF, 1-16 mg/l. The spontaneous and TNF-α (10 ng/ml induced expression and release of IL-8 and GM-CSF were measured using PCR and ELISA in the absence or presence of these antibiotics. Results The spontaneous IL-8 and GM-CSF release was significantly reduced with MXF (8 mg/l by 37 ± 20% and 45 ± 31%, respectively (both p Conclusion Using ALI cultures of hu-BEC we observed differential effects of antibiotics on spontaneous and TNF-α induced cytokine release. Our data suggest that MXF and AZM, beyond bactericidal effects, may attenuate the inflammatory process mediated by hu-BEC.

  5. Antibacterial effect of calcium hydroxide combined with chlorhexidine on Enterococcus faecalis: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Masoud SAATCHI

    2014-10-01

    Full Text Available Objective: Enterococcus faecalis (E. faecalis is the most frequently isolated strain in failed endodontic therapy cases since it is resistant to calcium hydroxide (CH. Whether a combination of CH and chlorhexidine (CHX is more effective than CH alone against E. faecalis is a matter of controversy. Thus, the aim of this study was to conduct a systematic review and meta-analysis of the literature. Material and Methods: A comprehensive search in PubMed, EMbase, EBSCOhost, The Cochrane Library, SciELO, and BBO databases, Clinical trials registers, Open Grey, and conference proceedings from the earliest available date to February 1, 2013 was carried out and the relevant articles were identified by two independent reviewers. Backward and forward search was performed and then inclusion and exclusion criteria were applied. The included studies were divided into "comparisons" according to the depth of sampling and dressing period of each medicament. Meta-analysis was performed using Stata software 10.0. The level of significance was set at 0.05. Results: Eighty-five studies were retrieved from databases and backward/forward searches. Fortyfive studies were considered as relevant (5 in vivo, 18 in vitro, 18 ex vivo, and 4 review articles. Nine studies were included for meta-analysis. Inter-observer agreement (Cohen kappa was 0.93. The included studies were divided into 21 comparisons for meta-analysis. Chi-square test showed the comparisons were heterogeneous (p<0.001. Random effect model demonstrated no significant difference between CH/CHX mixture and CH alone in their effect on E. faecalis (p=0.115. Conclusions: According to the evidence available now, mixing CH with CHX does not significantly increase the antimicrobial activity of CH against E. faecalis. It appears that mixing CH with CHX does not improve its ex vivo antibacterial property as an intracanal medicament against E. faecalis. Further in vivo studies are necessary to confirm and correlate

  6. Piper betle-mediated synthesis, characterization, antibacterial and rat splenocyte cytotoxic effects of copper oxide nanoparticles.

    Science.gov (United States)

    Praburaman, Loganathan; Jang, Jum-Suk; Muthusamy, Govarthanan; Arumugam, Sengottaiyan; Manoharan, Koildhasan; Cho, Kwang-Min; Min, Cho; Kamala-Kannan, Seralathan; Byung-Taek, Oh

    2016-09-01

    The study reports a simple, inexpensive, and eco-friendly synthesis of copper oxide nanoparticles (CuONPs) using Piper betle leaf extract. Formation of CuONPs was confirmed by UV-visible spectroscopy at 280 nm. Transmission electron microscopy (TEM) images showed that the CuONPs were spherical, with an average size of 50-100 nm. The scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS) peak was observed approximately at 1 and 8 keV. The X-ray diffraction (XRD) studies indicated that the particles were crystalline in nature. CuONPs effectively inhibited the growth of phytopathogens Ralstonia solanacearum and Xanthomonas axonopodis. The cytotoxic effect of the synthesized CuONPs was analyzed using rat splenocytes. The cell viability was decreased to 94% at 300 μg/mL.

  7. Antimicrobial polymers - The antibacterial effect of photoactivated nano titanium dioxide polymer composites

    Science.gov (United States)

    Huppmann, T.; Yatsenko, S.; Leonhardt, S.; Krampe, E.; Radovanovic, I.; Bastian, M.; Wintermantel, E.

    2014-05-01

    To obtain a polymer with antimicrobial properties for medical and sanitary applications nanoscale titanium dioxide (TiO2) particles have been incorporated into a medical grade polypropylene (PP) matrix with various filler contents (0 wt %, 2 wt %, 10 wt % and 15 wt %). The standard application of TiO2 for antimicrobial efficacy is to deposit a thin TiO2 coating on the surface. In contrast to the common way of applying a coating, TiO2 particles were applied into the bulk polymer. With this design we want to ensure antimicrobial properties even after application of impact effects that could lead to surface defects. The filler material (Aeroxide® TiO2 P25, Evonik) was applied via melt compounding and the compounding parameters were optimized with respect to nanoscale titanium dioxide. In a next step the effect of UV-irradiation on the compounds concerning their photocatalytic activity, which is related to the titanium dioxide amount, was investigated. The photocatalytic effect of TiO2-PP-composites was analyzed by contact angle measurement, by methylene blue testing and by evaluation of inactivation potential for Escherichia coli (E.coli) bacteria. The dependence of antimicrobial activity on the filler content was evaluated, and on the basis of different titanium dioxide fractions adequate amounts of additives within the compounds were discussed. Specimens displayed a higher photocatalytic and also antimicrobial activity and lower contact angles with increasing titania content. The results suggest that the presence of titania embedded in the PP matrix leads to a surface change and a photocatalytic effect with bacteria killing result.

  8. Antimicrobial polymers - The antibacterial effect of photoactivated nano titanium dioxide polymer composites

    Energy Technology Data Exchange (ETDEWEB)

    Huppmann, T., E-mail: teresa.huppmann@tum.de; Leonhardt, S., E-mail: stefan.leonhardt@mytum.de, E-mail: erhard.krampe@tum.de; Krampe, E., E-mail: stefan.leonhardt@mytum.de, E-mail: erhard.krampe@tum.de; Wintermantel, E., E-mail: wintermantel@tum.de [Institute of Medical and Polymer Engineering, Technische Universität München (Germany); Yatsenko, S., E-mail: s.yatsenko@skz.de; Radovanovic, I., E-mail: i.radovanovic@skz.de, E-mail: m.bastian@skz.de; Bastian, M., E-mail: i.radovanovic@skz.de, E-mail: m.bastian@skz.de [SKZ- German Plastics Center, Würzburg (Germany)

    2014-05-15

    To obtain a polymer with antimicrobial properties for medical and sanitary applications nanoscale titanium dioxide (TiO{sub 2}) particles have been incorporated into a medical grade polypropylene (PP) matrix with various filler contents (0 wt %, 2 wt %, 10 wt % and 15 wt %). The standard application of TiO{sub 2} for antimicrobial efficacy is to deposit a thin TiO{sub 2} coating on the surface. In contrast to the common way of applying a coating, TiO{sub 2} particles were applied into the bulk polymer. With this design we want to ensure antimicrobial properties even after application of impact effects that could lead to surface defects. The filler material (Aeroxide® TiO{sub 2} P25, Evonik) was applied via melt compounding and the compounding parameters were optimized with respect to nanoscale titanium dioxide. In a next step the effect of UV-irradiation on the compounds concerning their photocatalytic activity, which is related to the titanium dioxide amount, was investigated. The photocatalytic effect of TiO{sub 2}-PP-composites was analyzed by contact angle measurement, by methylene blue testing and by evaluation of inactivation potential for Escherichia coli (E.coli) bacteria. The dependence of antimicrobial activity on the filler content was evaluated, and on the basis of different titanium dioxide fractions adequate amounts of additives within the compounds were discussed. Specimens displayed a higher photocatalytic and also antimicrobial activity and lower contact angles with increasing titania content. The results suggest that the presence of titania embedded in the PP matrix leads to a surface change and a photocatalytic effect with bacteria killing result.

  9. Evaluation of antioxidant, antibacterial and cytotoxic effects of green synthesized silver nanoparticles by Piper longum fruit.

    Science.gov (United States)

    Reddy, N Jayachandra; Nagoor Vali, D; Rani, M; Rani, S Sudha

    2014-01-01

    Silver nanoparticles synthesized through bio-green method has been reported to have biomedical applications to control pathogenic microbes as it is cost effective compared to commonly used physical and chemical methods. In present study, silver nanoparticles were synthesized using aqueous Piper longum fruit extract (PLFE) and confirmed by UV-visible spectroscopy. The nanoparticles were spherical in shape with an average particle size of 46nm as determined by scanning electronic microscopy (SEM) and dynamic light scattering (DLS) particle size analyzer respectively. FT-IR spectrum revealed the capping of the phytoconstituents, probably polyphenols from P. longum fruit extract and stabilizing the nanoparticles. Further the ferric ion reducing test, confirmed that the capping agents were condensed tannins. The aqueous P. longum fruit extract (PLFE) and the green synthesized silver nanoparticles (PLAgNPs) showed powerful antioxidant properties in in vitro antioxidant assays. The results from the antimicrobial assays suggested that green synthesized silver nanoparticles (PLAgNPs) were more potent against pathogenic bacteria than the P. longum fruit extract (PLFE) alone. The nanoparticles also showed potent cytotoxic effect against MCF-7 breast cancer cell lines with an IC 50 value of 67μg/ml/24h by the MTT assay. These results support the advantages of using bio-green method for synthesizing silver nanoparticles with antioxidant, antimicrobial and cytotoxic activities those are simple and cost effective as well.

  10. Inhibitory effect of super-hydrophobicity on silver release and antibacterial properties of super-hydrophobic Ag/TiO2 nanotubes.

    Science.gov (United States)

    Zhang, Licheng; Zhang, Lihai; Yang, Yun; Zhang, Wei; Lv, Houchen; Yang, Fei; Lin, Changjian; Tang, Peifu

    2016-07-01

    The antibacterial properties of super-hydrophobic silver (Ag) on implant surface have not yet to be fully illuminated. In our study, we investigate the protective effects of super-hydrophobic coating of silver/titanium dioxide (Ag/TiO2 ) nanotubes against bacterial pathogens, as well as its pattern of Ag release. Ag/TiO2 nanotubes are prepared by a combination of electrochemical anodization and pulse electrodeposition. The super-hydrophobic coating is prepared by modifying the surface of Ag/TiO2 nanotubes with 1H, 1H, 2H, 2H-perfluorooctyl-triethoxysilane (PTES). Surface features and Ag release are examined by SEM, X-ray photoelectron spectroscopy, contact-angle measurement, and inductively coupled plasma-mass spectrometry (ICP-MS). The antibacterial activity of super-hydrophobic coating Ag/TiO2 nanotubes is investigated both in vitro and in vivo. Consequently, the super-hydrophobic coating on Ag/TiO2 nanotubes shows a regularly arranged structure; and nano-Ag particles (10-30 nm) are evenly distributed on the surface or inside the nanotubes. The contact angles of water on the super-hydrophobic coating Ag/TiO2 nanotubes are all above 150°. In addition, the super-hydrophobic character displays a certain conserved effect that contributes to the sustained release of Ag. The super-hydrophobic Ag/TiO2 nanotubes are also effective in inhibiting bacterial adhesion, killing the adhering bacteria and preventing postoperative infection in rabbits. Therefore, it is expected that the super-hydrophobic Ag/TiO2 nanotubes which can contain the release of Ag, leading to stable release, may show a consistent surface antibacterial capability. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1004-1012, 2016.

  11. Isolation and identification of biosurfactant-producing strains from the genus Pseudomonas aeruginosa and antibacterial effects of biosurfactant production in vitro

    Directory of Open Access Journals (Sweden)

    Salman Ahmady-Asbchin

    2013-01-01

    Full Text Available Introduction: Biosurfactants are amphiphilic biological compounds produced extracellularly or as part of the cell membranes by a variety of microorganisms. Because of their use in various industries, they are of a particular importance. The aim of this study was to identify a strain of bacteria of the genus Pseudomonas aeruginosa biosurfactant producers. Materials and methods: In this study, different samples of oil, water and soil contaminated with oil were prepared. Hemolytic activity, emulsification activity and measurement of surface tension were used and selected strains were identified by biochemical tests. The nature and effect of antibacterial biosurfactant was evaluated for strain selection.Results: In this study, eighty eight bacterial strains were isolated. Twenty four strains were isolated from the isolated strains with hemolytic activity. Among which, 14 strains have emulsification activity more than 70% and at last four strains reached surface tension to be less than 40 mN/m. Selected strain based on biochemical tests was recognized as a Pseudomonas aeruginosa. The nature of biosurfactant was determined by TLC, and proved to be of glycolipid kind. Therefore, the produced biosurfactant of the selected strain had antibacterial activity against six bacterial infectious. Sensitive bacteria to the effects of biosurfactant extract of Pseudomonas aeruginosa83, was Staphylococcus aureus and the most resistant bacteria to these extract, was the Proteus mirabilis. The results of MIC, MBC showed that MIC of the extract in concentration of 63 and 125 mg/ml on Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus respectively. Also, the MBC were extract in concentration of 63 and 125mg/ml on Staphylococcus epidermidis and Staphylococcus aureus respectively.Discussion and conclusion: Pseudomonas aeruginosa had high potential in reducing the surface tension and biosurfactant extracted had high antibacterial effects. Therefore, it

  12. Synthesis and Bioactivity of Novel Trisubstituted Triazole Nucleosides.

    Science.gov (United States)

    Wen, Yi-ning; Zhang, Zhi-feng; Liu, Ning-ning; Xiang, Yu-hong; Zhang, Zhuo-yong; Andrei, Graciela; Snoeck, Robert; Schols, Dominique; Zhang, Qing-shan; Wu, Qin-pei

    2016-01-01

    A series of novel trisubstituted 1,2,3-triazole purine nucleosides were efficiently synthesized via Huisgen 1,3-dipolar cycloaddition in good yields. Bioactivity against cytomegalovirus (CMV) and varicella-zoster virus (VZV) in human embryonic lung cell cultures was evaluated and all compounds show low antiviral activity.

  13. Synthesis of Peptidomimetic Conjugates of Acyclic Nucleoside Phosphonates

    Science.gov (United States)

    Serpi, Michaela; Zakharova, Valeria M.; Krylov, Ivan S.; McKenna, Charles E.

    2010-01-01

    Cyclic nucleoside phosphonates connected through a P-O-C linkage to a promoiety represent a class of prodrugs designed to overcome the low oral bioavailability of parent antiviral acyclic nucleoside phosphonates. In our prodrug approach, a non-toxic promoiety such as an amino acid or dipeptide is conjugated to the cyclic form of the parent drug by esterification of the phosphonic acid moiety by an alcoholic amino acid side chain (Ser, Tyr, and analogues) or through a glycol linker. For the biological evaluation and investigation of the pharmacokinetic profiles of these modified nucleoside phosphonates, a reliable synthetic procedure that allows preparation of sufficient amount of potential prodrugs is needed. This unit describes a method for generating peptidomimetic conjugates of two potent antiviral acyclic nucleoside phosphonates: 1-[(2S)-3-hydroxy-2-phosphonomethoxypropyl]cytosine ((S)-HPMPC, and 9-[(2S)-3-hydroxy-2-phosphonomethoxypropyl]adenine ((S)-HPMPA). Two alternate strategies allowing synthesizing selected amino acid, dipeptide, or ethylene glycol-linked amino acid prodrugs of (S)-HPMPC and (S)-HPMPA in solution and using a solid-phase approach are presented. PMID:21154529

  14. Synthesis, bioanalysis and pharmacology of nucleoside and nucleotide analogs

    NARCIS (Netherlands)

    Jansen, R.S.

    2009-01-01

    Nucleoside analogs are an important class of drugs in anticancer and antiviral therapy. The compounds are, however, only active after intracellular conversion to their mono-, di- and triphosphate nucleotide form. In this thesis the development of sensitive liquid chromatography coupled to tandem mas

  15. Nucleoside triphosphate synthesis catalysed by adenylate kinase is ADP dependent

    DEFF Research Database (Denmark)

    Willemoes, Martin; Kilstrup, M.

    2005-01-01

    Adenylate kinase (Adk) that catalyses the synthesis of ADP from ATP and AMP has also been shown to perform an ATP dependent phosphorylation of ribo- and deoxynucleoside diphosphates to their corresponding nucleoside triphosphate; ATP + (d)NDP ¿ ADP + (d)NTP. This reaction, suggested to occur...

  16. Deoxyribonucleoside kinases activate nucleoside antibiotics in severely pathogenic bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Shannon, O.; Clausen, A.R.;

    2007-01-01

    Common bacterial pathogens are becoming progressively more resistant to traditional antibiotics, representing a major public-health crisis. Therefore, there is a need for a variety of antibiotics with alternative modes of action. In our study, several nucleoside analogs were tested against...... alternative for combating pathogenic bacteria....

  17. Evaluation of antioxidant, antibacterial and cytotoxic effects of green synthesized silver nanoparticles by Piper longum fruit

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, N. Jayachandra; Nagoor Vali, D.; Rani, M.; Rani, S. Sudha, E-mail: sadrassudha@gmail.com

    2014-01-01

    Silver nanoparticles synthesized through bio-green method has been reported to have biomedical applications to control pathogenic microbes as it is cost effective compared to commonly used physical and chemical methods. In present study, silver nanoparticles were synthesized using aqueous Piper longum fruit extract (PLFE) and confirmed by UV–visible spectroscopy. The nanoparticles were spherical in shape with an average particle size of 46 nm as determined by scanning electronic microscopy (SEM) and dynamic light scattering (DLS) particle size analyzer respectively. FT-IR spectrum revealed the capping of the phytoconstituents, probably polyphenols from P. longum fruit extract and stabilizing the nanoparticles. Further the ferric ion reducing test, confirmed that the capping agents were condensed tannins. The aqueous P. longum fruit extract (PLFE) and the green synthesized silver nanoparticles (PLAgNPs) showed powerful antioxidant properties in in vitro antioxidant assays. The results from the antimicrobial assays suggested that green synthesized silver nanoparticles (PLAgNPs) were more potent against pathogenic bacteria than the P. longum fruit extract (PLFE) alone. The nanoparticles also showed potent cytotoxic effect against MCF-7 breast cancer cell lines with an IC 50 value of 67 μg/ml/24 h by the MTT assay. These results support the advantages of using bio-green method for synthesizing silver nanoparticles with antioxidant, antimicrobial and cytotoxic activities those are simple and cost effective as well. - Highlights: • 46 nm spherical shaped P. longum fruit silver nanoparticles was prepared. • Capping and reducing bioactive plant compounds with in nanoparticles were condensed tannins. • Particles are potent antioxidant and anti microbial in biological systems. • They are cytotoxic against MCF-7 cell lines.

  18. PENGARUH pH, NaCl DAN PEMANASAN TERHADAP STABILITAS ANTIBAKTERI BUNGA KECOMBRANG DAN APLIKASINYA PADA DAGING SAPI GILING [Effects of pH, Nacl and Teating on the Antibacterial Stability of Kecombrang

    Directory of Open Access Journals (Sweden)

    Rifda Naufalin1

    2006-12-01

    Full Text Available The effect of pH (4-9, NaCl concentration (1-5%, temperature and heating time (80, 100 and 1210C for 10, 20 and 30 minute on the antibacterial effectivity of ethyl acetate and ethanol kecombrang extract were analysed. Both ethyl acetate and ethanol extracts showed antibacterial activity at pH 4-8, but its activity gradually decreased at higher pH. At pH 9, only ethanol extract still showed antibacterial activity. Addition of 1-4% NaCl on ethyl acetate and ethanol extract still showed antibacterial activity. Heating the extracts at 80-100 0C for 10-30 minutes and 1210C for 10 minutes did not haves significantly affect on the antibacterial activity of both ethyl acetate and ethanol extracts. Application of ethyl acetate extract at the concentration of 1 and 3 MIC on minced meat were still effective to reduce the viable bacteria until 7 days and 5 MIC was still effective until 9 days.

  19. Antibacterial Activity of Geminized Amphiphilic Cationic Homopolymers.

    Science.gov (United States)

    Wang, Hui; Shi, Xuefeng; Yu, Danfeng; Zhang, Jian; Yang, Guang; Cui, Yingxian; Sun, Keji; Wang, Jinben; Yan, Haike

    2015-12-22

    The current study is aimed at investigating the effect of cationic charge density and hydrophobicity on the antibacterial and hemolytic activities. Two kinds of cationic surfmers, containing single or double hydrophobic tails (octyl chains or benzyl groups), and the corresponding homopolymers were synthesized. The antimicrobial activity of these candidate antibacterials was studied by microbial growth inhibition assays against Escherichia coli, and hemolysis activity was carried out using human red blood cells. It was interestingly found that the homopolymers were much more effective in antibacterial property than their corresponding monomers. Furthermore, the geminized homopolymers had significantly higher antibacterial activity than that of their counterparts but with single amphiphilic side chains in each repeated unit. Geminized homopolymers, with high positive charge density and moderate hydrophobicity (such as benzyl groups), combine both advantages of efficient antibacterial property and prominently high selectivity. To further explain the antibacterial performance of the novel polymer series, the molecular interaction mechanism is proposed according to experimental data which shows that these specimens are likely to kill microbes by disrupting bacterial membranes, leading them unlikely to induce resistance.

  20. Intrinsic Hydrophobic Cairnlike Multilayer Films for Antibacterial Effect with Enhanced Durability.

    Science.gov (United States)

    Jeong, Hyejoong; Heo, Jiwoong; Son, Boram; Choi, Daheui; Park, Tai Hyun; Chang, Minwook; Hong, Jinkee

    2015-12-01

    One important aspect of nanotechnology includes thin films capable of being applied to a wide variety of surfaces. Indispensable functions of films include controlled surface energy, stability, and biocompatibility in physiological systems. In this study, we explored the ancient Asian coating material "lacquer" to enhance the physiological and mechanical stability of nanofilms. Lacquer is extracted from the lacquer tree and its main component called urushiol, which is a small molecule that can produce an extremely strong coating. Taking full advantage of layer-by-layer assembly techniques, we successfully fabricated urushiol-based thin films composed of small molecule/polymer multilayers by controlling their molecular interaction. Unique cairnlike nanostructures in this film, produced by urushiol particles, have advantages of intrinsic hydrophobicity and durability against mechanical stimuli at physiological environment. We demonstrated the stability tests as well as the antimicrobial effects of this film.

  1. Effect of capping agents on optical and antibacterial properties of cadmium selenide quantum dots

    Indian Academy of Sciences (India)

    Deepika; Rakesh Dhar; Suman Singh; Atul Kumar

    2015-09-01

    Cadmium selenide quantum dots (CdSe QDs) were synthesized in aqueous phase by the freezing temperature injection technique using different capping agents (viz. thioglycolic acid, 1-thioglycerol, L-cysteine). Absorption spectra of CdSe QDs exhibited a blue shift as compared to its bulk counterpart, which is an indication of quantum confinement effect. The photoluminescence spectra of CdSe QDs confirmed that the particles are poly-dispersed and possess enhanced luminescent property, depending upon the chemical nature of capping agents. The QDs have been characterized by Fourier-transform infrared spectroscopy, atomic absorption spectroscopy and transmission electron microscopy. Further, antimicrobial activity of as-prepared QDs has also been investigated using the disk diffusion method.

  2. Effect of doping on structural and optical properties of ZnO nanoparticles: study of antibacterial properties

    Science.gov (United States)

    Maddahi, P.; Shahtahmasebi, N.; Kompany, A.; Mashreghi, M.; Safaee, S.; Roozban, F.

    2014-06-01

    Sol-gel method was successfully used for synthesis of ZnO nanoparticles doped with 10 % Mg or Cu. The structure, morphology and optical properties of the prepared nanoparticles were studied as a function of doping content. The synthesized ZnO:(Mg/Cu) samples were characterized using XRD, TEM, FTIR and UV-Vis spectroscopy techniques. The samples show hexagonal wurtzite structure, and the phase segregation takes place for Cu doping. Optical studies revealed that Mg doping increases the energy band gap while Cu incorporation results in decrease of the band gap. The antibacterial activities of the nanoparticles were tested against Escherichia coli (Gram negative bacteria) cultures. It was found that both pure and doped ZnO nanosuspensions show good antibacterial activity which increases with copper doping, and slightly decreases with adding Mg.

  3. Efficient drug delivery to alveolar macrophages and lung epithelial lining fluid following pulmonary administration of liposomal ciprofloxacin in rats with pneumonia and estimation of its antibacterial effects.

    Science.gov (United States)

    Chono, Sumio; Tanino, Tomoharu; Seki, Toshinobu; Morimoto, Kazuhiro

    2008-10-01

    The efficacy of pulmonary administration of liposomal ciprofloxacin (CPFX) in pneumonia was evaluated. In brief, the pharmacokinetics following pulmonary administration of liposomal CPFX (particle size, 1,000 nm; dose, 200 microg/kg) were examined in rats with lipopolysaccharide-induced pneumonia as an experimental pneumonia model. Furthermore, the antibacterial effects of liposomal CPFX against the pneumonic causative organisms were estimated by pharmacokinetic/pharmacodynamic (PK/PD) analysis. The time-courses of the concentration of CPFX in alveolar macrophages (AMs) and lung epithelial lining fluid (ELF) following pulmonary administration of liposomal CPFX to rats with pneumonia were markedly higher than that following the administration of free CPFX (200 microg/kg). The time course of the concentrations of CPFX in plasma following pulmonary administration of liposomal CPFX was markedly lower than that in AMs and ELF. These results indicate that pulmonary administration of liposomal CPFX was more effective in delivering CPFX to AMs and ELF compared with free CPFX, and it avoids distribution of CPFX to the blood. According to PK/PD analysis, the liposomal CPFX exhibited potent antibacterial effects against the causative organisms of pneumonia. This study indicates that pulmonary administration of CPFX could be an effective technique for the treatment of pneumonia.

  4. 芦荟蒽醌类物质的提取及其抑菌性研究%Extraction of Aloe Anthraquinones and Analysis of Its Antibacterial Effect

    Institute of Scientific and Technical Information of China (English)

    秦伟; 乔丹; 宝力德

    2011-01-01

    本试验利用超声波提取库拉索芦荟中蒽醌类物质,测定其含量,并对枯草芽孢杆菌、大肠杆菌及金黄色葡萄球菌进行抑菌性研究.用滤纸片法、固体稀释法及最小抑菌浓度法(MIC)分别检测芦荟蒽醌类物质对各种菌的抑菌性,并比较分析3种方法的抑菌效果.由固体稀释法测定芦荟蒽醌提取液的抑菌效果可知,蒽醌类物质百分浓度越高,菌落数越少,显示出越高的抑菌性.最小抑菌浓度法(MIC)测出,芦荟蒽醌提取液对大肠杆菌、金色葡萄球菌的MIC为90%,对枯草芽孢杆菌的MIC为80%,显示出MIC都较高,说明低浓度的芦荟蒽醌类抑菌能力有限,需要较高的浓度才能抑制菌生长.%In this study, the Aloe vera L. anthraquinones had been extracted by ultrasonic extraction and its content had been determined. The antibacterial effect of the Aloe anthraquinones on the Bacillus subtilis,Escherichia coli, Staphylococcus aureus had been investigated. The filter paper method, solid dilution method and minimum inhibitory concentration (MIC) method had been used to determine the antibacterial effect of the Aloe anthraquinones, and the efeects of this three methods had been compared. The solid dilution method showed that the high concentration of Aloe anthraquinone extract had the significant antibacterial effect. The minimum inhibitory concentration (MIC) was 90% for E. coli and S. aureus, and 80% for B. subtilis. The MIC of the Aloe anthraquinones showed a higher values, that meant antibacterial activity of Aloe anthraquinones was limited, only the Aloe anthraquinones with higher concentrations could inhibit the bacteria growth.

  5. Antibacterial Effects of a Cell-Penetrating Peptide Isolated from Kefir.

    Science.gov (United States)

    Miao, Jianyin; Guo, Haoxian; Chen, Feilong; Zhao, Lichao; He, Liping; Ou, Yangwen; Huang, Manman; Zhang, Yi; Guo, Baoyan; Cao, Yong; Huang, Qingrong

    2016-04-27

    Kefir is a traditional fermented milk beverage used throughout the world for centuries. A cell-penetrating peptide, F3, was isolated from kefir by Sephadex G-50 gel filtration, DEAE-52 ion exchange, and reverse-phase high-performance liquid chromatography. F3 was determined to be a low molecular weight peptide containing one leucine and one tyrosine with two phosphate radicals. This peptide displayed antimicrobial activity across a broad spectrum of organisms including several Gram-positive and Gram-negative bacteria as well as fungi, with minimal inhibitory concentration (MIC) values ranging from 125 to 500 μg/mL. Cellular penetration and accumulation of F3 were determined by confocal laser scanning microscopy. The peptide was able to penetrate the cellular membrane of Escherichia coli and Staphylococcus aureus. Changes in cell morphology were observed by scanning electron microscopy (SEM). The results indicate that peptide F3 may be a good candidate for use as an effective biological preservative in agriculture and the food industry.

  6. The Antibacterial Effect of Ethanol Extract of Polish Propolis on Mutans Streptococci and Lactobacilli Isolated from Saliva

    Directory of Open Access Journals (Sweden)

    Arkadiusz Dziedzic

    2013-01-01

    Full Text Available Dental caries occurrence is caused by the colonization of oral microorganisms and accumulation of extracellular polysaccharides synthesized by Streptococcus mutans with the synergistic influence of Lactobacillus spp. bacteria. The aim of this study was to determine ex vivo the antibacterial properties of ethanol extract of propolis (EEP, collected in Poland, against the main cariogenic bacteria: salivary mutans streptococci and lactobacilli. The isolation of mutans streptococci group bacteria (MS and Lactobacillus spp. (LB from stimulated saliva was performed by in-office CRT bacteria dip slide test. The broth diffusion method and AlamarBlue assay were used to evaluate the antimicrobial activity of EEP, with the estimation of its minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC. The biochemical composition of propolis components was assessed. The mean MIC and MBC values of EEP, in concentrations ranging from 25 mg/mL to 0.025 mg/mL, for the MS and LB were found to be 1.10 mg/mL versus 0.7 mg/mL and 9.01 mg/mL versus 5.91 mg/mL, respectively. The exposure to an extract of Polish propolis affected mutans streptococci and Lactobacillus spp. viability, exhibiting an antibacterial efficacy on mutans streptococci group bacteria and lactobacilli saliva residents, while lactobacilli were more susceptible to EEP. Antibacterial measures containing propolis could be the local agents acting against cariogenic bacteria.

  7. Two nucleoside uptake systems in Lactococcus lactis: Competition between purine nucleosides and cytidine allows for modulation of intracellular nucleotide pools

    DEFF Research Database (Denmark)

    Martinussen, Jan; Wadskov-Hansen, Steen Lyders Lerche; Hammer, Karin

    2003-01-01

    in Lactococcus lactis were investigated by measuring the uptake of radioactively labeled nucleosides. The K. for for inosine, cytidine, and uridine was determined to be in the micromolar range. Furthermore, it was found that cytidine and inosine are competitive inhibitors of each other, whereas no competition...

  8. Focus on Chirality of HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors

    Directory of Open Access Journals (Sweden)

    Valeria Famiglini

    2016-02-01

    Full Text Available Chiral HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs are of great interest since one enantiomer is often more potent than the corresponding counterpart against the HIV-1 wild type (WT and the HIV-1 drug resistant mutant strains. This review exemplifies the various studies made to investigate the effect of chirality on the antiretroviral activity of top HIV-1 NNRTI compounds, such as nevirapine (NVP, efavirenz (EFV, alkynyl- and alkenylquinazolinone DuPont compounds (DPC, diarylpyrimidine (DAPY, dihydroalkyloxybenzyloxopyrimidine (DABO, phenethylthiazolylthiourea (PETT, indolylarylsulfone (IAS, arylphosphoindole (API and trifluoromethylated indole (TFMI The chiral separation, the enantiosynthesis, along with the biological properties of these HIV-1 NNRTIs, are discussed.

  9. Butyrate enhances antibacterial effects while suppressing other features of alternative activation in IL-4-induced macrophages.

    Science.gov (United States)

    Fernando, Maria R; Saxena, Alpana; Reyes, José-Luis; McKay, Derek M

    2016-05-15

    The short-chain fatty acid butyrate is produced by fermentation of dietary fiber by the intestinal microbiota; butyrate is the primary energy source of colonocytes and has immunomodulatory effects. Having shown that macrophages differentiated with IL-4 [M(IL-4)s] can suppress colitis, we hypothesized that butyrate would reinforce an M(IL-4) phenotype. Here, we show that in the presence of butyrate M(IL-4)s display reduced expression of their hallmark markers Arg1 and Ym1 and significantly suppressed LPS-induced nitric oxide, IL-12p40, and IL-10 production. Butyrate treatment likely altered the M(IL-4) phenotype via inhibition of histone deacetylation. Functionally, M(IL-4)s treated with butyrate showed increased phagocytosis and killing of bacteria, compared with M(IL-4) and this was not accompanied by enhanced proinflammatory cytokine production. Culture of regulatory T cells with M(IL-4)s and M(IL-4 + butyrate)s revealed that both macrophage subsets suppressed expression of the regulatory T-cell marker Foxp3. However, Tregs cocultured with M(IL-4 + butyrate) produced less IL-17A than Tregs cocultured with M(IL-4). These data illustrate the importance of butyrate, a microbial-derived metabolite, in the regulation of gut immunity: the demonstration that butyrate promotes phagocytosis in M(IL-4)s that can limit T-cell production of IL-17A reveals novel aspects of bacterial-host interaction in the regulation of intestinal homeostasis.

  10. Feasibility, efficacy, and adverse effects of outpatient antibacterial prophylaxis in children with acute myeloid leukemia

    Science.gov (United States)

    Inaba, Hiroto; Gaur, Aditya H; Cao, Xueyuan; Flynn, Patricia M; Pounds, Stanley B; Avutu, Viswatej; Marszal, Lindsay N; Howard, Scott C; Pui, Ching-Hon; Ribeiro, Raul C; Hayden, Randall T; Rubnitz, Jeffrey E

    2014-01-01

    BACKGROUND Intensive chemotherapy for pediatric acute myeloid leukemia (AML) incurs the risk of infectious complications, but the benefits of antibiotic prophylaxis remain unclear. METHODS In 103 children treated on the AML02 protocol between October 2002 and October 2008 at St. Jude Children’s Research Hospital, we retrospectively assessed the effect of antibiotic prophylaxis on the frequency of febrile neutropenia, clinically or microbiologically confirmed infections (including bacteremia), and antibiotic resistance, and on the results of nasal and rectal surveillance cultures. Initially, patients received no prophylaxis or oral cephalosporin (Group A). Then the protocol was amended to give intravenous cefepime alone or intravenous vancomycin plus either oral cephalosporin, oral ciprofloxacin, or intravenous cefepime (Group B). RESULTS There were 334 infectious episodes. Group A had a significantly greater frequency of documented infections and bacteremia (both P < .0001) (including gram-positive and gram-negative bacteremia, P = .0003 and .001, respectively) than Group B, especially viridans streptococcal bacteremia (P = .001). The incidence of febrile neutropenia without documented infection was not different between the two groups. Five cases of bacteremia with vancomycin-resistant enterococci (VRE) occurred in group B (vs. none in Group A), without related mortality. Two of these cases were preceded by positive VRE rectal surveillance cultures. CONCLUSIONS Outpatient intravenous antibiotic prophylaxis is feasible in children with AML and reduces the frequency of documented infection but not of febrile neutropenia. Despite emergence of VRE bacteremia, the benefits favor antibiotic prophylaxis. Creative approaches to shorten the duration of prophylaxis and thereby minimize resistance should be explored. PMID:24677028

  11. Enantioselective Supramolecular Carriers for Nucleoside Drugs. A Thermodynamic and Kinetic Gas Phase Investigation

    Science.gov (United States)

    Fraschetti, Caterina; Filippi, Antonello; Crestoni, Maria Elisa; Villani, Claudio; Roselli, Graziella; Mortera, Stefano Levi; Speranza, Maurizio

    2012-10-01

    The enantioselective interactions between chiral tetra-amidic receptors and nucleosides have been investigated by the ESI-IT-MS and ESI-FT-ICR-MS methodologies. Configurational effects on the CID fragmentation of diastereomeric [ M H 2 •H•A] + aggregates (A = 2'-deoxycytidine dC, citarabine ( ara-C) were found to be mostly offset by isotope effect in [ S X 2 •H•A] + (X = H, D) differently from the results obtained on the analogues (A = cytidine C and gemcitabine G). This result points the involvement of two different nucleoside/tetraamide isoforms. The structural differences of the [ M H 2 •H•A] + (A = C and G) complexes vs. the [ M H 2 •H•A] + ( dC and ara-C) ones is fully confirmed by the kinetics of their uptake of the 2-aminobutane enantiomers, measured by FT-ICR mass spectrometry. Indeed, uptake of the 2-aminobutane enantiomers by [ M H n •H•A] + (n = 1,2; A = dC and ara-C) complexes is reversible, while that by [ M H n •H•A] + (n = 1,2; A = C and G) is not. The most encouraging result concerning the measured fragmentation and kinetic differences between C and ara-C, that are just epimers, indicates the possibility to subtly modulate the non-covalent drug/receptor interactions, through the electronic properties of the 2'-substituent on the nucleoside furanose ring, and furthermore on its three-dimensional position.

  12. Nucleoside drugs induce cellular differentiation by caspase-dependent degradation of stem cell factors.

    Directory of Open Access Journals (Sweden)

    Tanja Musch

    Full Text Available BACKGROUND: Stem cell characteristics are an important feature of human cancer cells and play a major role in the therapy resistance of tumours. Strategies to target cancer stem cells are thus of major importance for cancer therapy. Differentiation therapy by nucleoside drugs represents an attractive approach for the elimination of cancer stem cells. However, even if it is generally assumed that the activity of these drugs is mediated by their ability to modulate epigenetic pathways, their precise mode of action remains to be established. We therefore analysed the potential of three nucleoside analogues to induce differentiation of the embryonic cancer stem cell line NTERA 2 D1 and compared their effect to the natural ligand retinoic acid. METHODOLOGY/PRINCIPAL FINDINGS: All nucleoside analogues analyzed, but not retinoic acid, triggered proteolytic degradation of the Polycomb group protein EZH2. Two of them, 3-Deazaneplanocin A (DZNep and 2'-deoxy-5-azacytidine (decitabine, also induced a decrease in global DNA methylation. Nevertheless, only decitabine and 1beta-arabinofuranosylcytosine (cytarabine effectively triggered neuronal differentiation of NT2 cells. We show that drug-induced differentiation, in contrast to retinoic acid induction, is caused by caspase activation, which mediates depletion of the stem cell factors NANOG and OCT4. Consistent with this observation, protein degradation and differentiation could be counteracted by co-treatment with caspase inhibitors or by depletion of CASPASE-3 and CASPASE-7 through dsRNA interference. In agreement with this, OCT4 was found to be a direct in-vitro-target of CASPASE-7. CONCLUSIONS/SIGNIFICANCE: We show that drug-induced differentiation is not a consequence of pharmacologic epigenetic modulation, but is induced by the degradation of stem-cell-specific proteins by caspases. Our results thus uncover a novel pathway that induces differentiation of embryonic cancer stem cells and is triggered by

  13. Enhancement of Peripheral Nerve Regrowth by the Purine Nucleoside Analog and Cell Cycle Inhibitor, Roscovitine

    Science.gov (United States)

    Law, Vincent; Dong, Sophie; Rosales, Jesusa L.; Jeong, Myung-Yung; Zochodne, Douglas; Lee, Ki-Young

    2016-01-01

    Peripheral nerve regeneration is a slow process that can be associated with limited outcomes and thus a search for novel and effective therapy for peripheral nerve injury and disease is crucial. Here, we found that roscovitine, a synthetic purine nucleoside analog, enhances neurite outgrowth in neuronal-like PC12 cells. Furthermore, ex vivo analysis of pre-injured adult rat dorsal root ganglion (DRG) neurons showed that roscovitine enhances neurite regrowth in these cells. Likewise, in vivo transected sciatic nerves in rats locally perfused with roscovitine had augmented repopulation of new myelinated axons beyond the transection zone. By mass spectrometry, we found that roscovitine interacts with tubulin and actin. It interacts directly with tubulin and causes a dose-dependent induction of tubulin polymerization as well as enhances Guanosine-5′-triphosphate (GTP)-dependent tubulin polymerization. Conversely, roscovitine interacts indirectly with actin and counteracts the inhibitory effect of cyclin-dependent kinases 5 (Cdk5) on Actin-Related Proteins 2/3 (Arp2/3)-dependent actin polymerization, and thus, causes actin polymerization. Moreover, in the presence of neurotrophic factors such as nerve growth factor (NGF), roscovitine-enhanced neurite outgrowth is mediated by increased activation of the extracellular signal-regulated kinases 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) pathways. Since microtubule and F-actin dynamics are critical for axonal regrowth, the ability of roscovitine to activate the ERK1/2 and p38 MAPK pathways and support polymerization of tubulin and actin indicate a major role for this purine nucleoside analog in the promotion of axonal regeneration. Together, our findings demonstrate a therapeutic potential for the purine nucleoside analog, roscovitine, in peripheral nerve injury.

  14. Antibacterial properties of nanoparticles.

    Science.gov (United States)

    Hajipour, Mohammad J; Fromm, Katharina M; Ashkarran, Ali Akbar; Jimenez de Aberasturi, Dorleta; de Larramendi, Idoia Ruiz; Rojo, Teofilo; Serpooshan, Vahid; Parak, Wolfgang J; Mahmoudi, Morteza

    2012-10-01

    Antibacterial agents are very important in the textile industry, water disinfection, medicine, and food packaging. Organic compounds used for disinfection have some disadvantages, including toxicity to the human body, therefore, the interest in inorganic disinfectants such as metal oxide nanoparticles (NPs) is increasing. This review focuses on the properties and applications of inorganic nanostructured materials and their surface modifications, with good antimicrobial activity. Such improved antibacterial agents locally destroy bacteria, without being toxic to the surrounding tissue. We also provide an overview of opportunities and risks of using NPs as antibacterial agents. In particular, we discuss the role of different NP materials.

  15. Research Progress of Antibacterial Effect of Several Kinds of Spices%几种香辛料抗菌作用的研究进展

    Institute of Scientific and Technical Information of China (English)

    黄敏欣; 赵文红; 白卫东; 钱敏

    2015-01-01

    Spices have unique irritating aroma,being used for the seasoning of food to provide flavor and aroma.Importantly,spices have certain antibacterial effects,which are effective sources of natural preservative. In this paper, the antibacterial effects of several kinds of spices, such as Foeniculum vulgare Mill,onion,acorus calamus,licorice are summarized.It is expected to make some contribution to the development of natural preservatives.%香辛料具有一种独特的刺激性香味,用于食品的调味,赋予香气,同时还具有一定的抗菌作用,成为天然防腐剂的重要来源之一。综述小茴香、洋葱、菖蒲、甘草等几种香辛料的抗菌作用,以期为小茴香、洋葱、菖蒲、甘草等几种香辛料作为天然防腐剂的开发有所贡献。

  16. The synthesis and characterization of poly({gamma}-glutamic acid)-coated magnetite nanoparticles and their effects on antibacterial activity and cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Inbaraj, B; Kao, T H; Tsai, T Y; Chiu, C P; Kumar, R; Chen, B H, E-mail: 002622@mail.fju.edu.tw [Department of Food Science, Fu Jen University, Taipei 242, Taiwan (China)

    2011-02-18

    Magnetite nanoparticles (MNPs) modified with sodium and calcium salts of poly({gamma}-glutamic acid) (NaPGA and CaPGA) were synthesized by the coprecipitation method, followed by characterization and evaluation of their antibacterial and cytotoxic effects. Superparamagnetic MNPs are particularly attractive for magnetic driving as well as bacterial biofilm and cell targeting in in vivo applications. Characterization of synthesized MNPs by the Fourier transform infrared spectra and magnetization curves confirmed the PGA coating on MNPs. The mean diameter of NaPGA- and CaPGA-coated MNPs as determined by transmission electron microscopy was 11.8 and 14 nm, respectively, while the x-ray diffraction pattern revealed the as-synthesized MNPs to be pure magnetite. Based on agar dilution assay, both NaPGA- and CaPGA-coated MNPs showed a lower minimum inhibitory concentration in Salmonella enteritidis SE 01 than the commercial antibiotics linezolid and cefaclor, but the former was effective against Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 10832, whereas the latter was effective against Escherichia coli O157:H7 TWC 01. An in vitro cytotoxicity study in human skin fibroblast cells as measured by MTT assay implied the as-synthesized MNPs to be nontoxic. This outcome demonstrated that both {gamma}-PGA-modified MNPs are cytocompatible and possess antibacterial activity in vitro, and thereby should be useful in in vivo studies for biomedical applications.

  17. Preparation of cellulose fibres with antibacterial Ag-loading nano-SiO2

    Indian Academy of Sciences (India)

    Wang Shuhua; Niu Runlin; Jia Husheng; Wei Liqiao; Daijinming; Liu Xuguang; Xu Bingshe

    2011-07-01

    The antibacterial cellulose fibres with acrylamide polymerization and Ag-loading SiO2 nanoantibacterial materials were successfully prepared. The chemical structures and morphologies of antibacterial cellulose fibres were characterized by Fourier transformation infrared spectrum (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that acrylamide was adsorbed on the surface of the cellulose fibres and formed a layer with thickness of 50–100 nm. The nano-SiO2 composite antibacterial materials were combined with cellulose fibres firmly by infiltrating into polyacrylamide layer about 100 nm. The antibacterial cellulose fibres with antibacterial layer owned excellent antibacterial effect.

  18. Comparative analysis of antibacterial activity of povidone iodine and homoeopathic mother tinctures as antiseptics

    Directory of Open Access Journals (Sweden)

    Muhammad Mohsin Zaman

    2016-01-01

    Conclusion: This study confirms the antibacterial activity and more effectiveness of Thuja occidentalis and Rhus glabra mother tinctures than povidone iodine. The other tested mother tinctures also have antibacterial activity against tested bacteria, except Echinacea.

  19. A STUDY OF THE NUCLEOSIDE TRI- AND DIPHOSPHATE ACTIVITIES OF RAT LIVER MICROSOMES

    Science.gov (United States)

    Ernster, Lars; Jones, Lois C.

    1962-01-01

    Rat liver microsomes catalyze the hydrolysis of the triphosphates of adenosine, guanosine, uridine, cytidine, and inosine into the corresponding diphosphates and inorganic orthophosphate. The activities are stimulated by Na2S2O4, and inhibited by atebrin, chlorpromazine, sodium azide, and deaminothyroxine. Sodium deoxycholate inhibits the ATPase activity in a progressive manner; the release of orthophosphate from GTP and UTP is stimulated by low, and inhibited by high, concentrations of deoxycholate, and that from CTP and ITP is unaffected by low, and inhibited by high, concentrations of deoxycholate. Subfractionation of microsomes with deoxycholate into ribosomal, membrane, and soluble fractions reveals a concentration of the triphosphatase activity in the membrane fraction. Rat liver microsomes also catalyze the hydrolysis of the diphosphates of the above nucleosides into the corresponding monophosphates and inorganic orthophosphate. Deoxycholate strongly enhances the GDPase, UDPase, and IDPase activities while causing no activation or even inhibition of the ADPase and CDPase activities. The diphosphatase is unaffected by Na2S2O4 and is inhibited by azide and deaminothyroxine but not by atebrin or chlorpromazine. Upon fractionation of the microsomes with deoxycholate, a large part of the GDPase, UDPase, and IDPase activities is recovered in the soluble fraction. Mechanical disruption of the microsomes with an Ultra Turrax Blender both activates and releases the GDPase, UDPase, and IDPase activities, and the former effect occurs more readily than the latter. The GDPase, UDPase, and IDPase activities of the rat liver cell reside almost exclusively in the microsomal fraction, as revealed by comparative assays of the mitochondrial, microsomal, and final supernatant fractions of the homogenate. The microsomes exhibit relatively low nucleoside monophosphatase and inorganic pyrophosphatase activities, and these are unaffected by deoxycholate or mechanical treatment

  20. Antibacterials in Household Products

    Science.gov (United States)

    ... residue-producing ). Common examples of this group are triclosan, triclocarban, and benzalkonium chloride. Did you know that over 1000 commercial products contain triclosan or other biocide agents? Antibacterials in household products ...

  1. The SLC28 (CNT) and SLC29 (ENT) nucleoside transporter families: a 30-year collaborative odyssey.

    Science.gov (United States)

    Young, James D

    2016-06-15

    Specialized nucleoside transporter (NT) proteins are required for passage of nucleosides and hydrophilic nucleoside analogues across biological membranes. Physiologic nucleosides serve as central salvage metabolites in nucleotide biosynthesis, and nucleoside analogues are used as chemotherapeutic agents in the treatment of cancer and antiviral diseases. The nucleoside adenosine modulates numerous cellular events via purino-receptor cell signalling pathways. Human NTs are divided into two structurally unrelated protein families: the SLC28 concentrative nucleoside transporter (CNT) family and the SLC29 equilibrative nucleoside transporter (ENT) family. Human CNTs are inwardly directed Na(+)-dependent nucleoside transporters found predominantly in intestinal and renal epithelial and other specialized cell types. Human ENTs mediate bidirectional fluxes of purine and pyrimidine nucleosides down their concentration gradients and are ubiquitously found in most, possibly all, cell types. Both protein families are evolutionarily old: CNTs are present in both eukaryotes and prokaryotes; ENTs are widely distributed in mammalian, lower vertebrate and other eukaryote species. This mini-review describes a 30-year collaboration with Professor Stephen Baldwin to identify and understand the structures and functions of these physiologically and clinically important transport proteins.

  2. Ethenoguanines undergo glycosylation by nucleoside 2'-deoxyribosyltransferases at non-natural sites.

    Directory of Open Access Journals (Sweden)

    Wenjie Ye

    Full Text Available Deoxyribosyl transferases and functionally related purine nucleoside phosphorylases are used extensively for synthesis of non-natural deoxynucleosides as pharmaceuticals or standards for characterizing and quantitating DNA adducts. Hence exploring the conformational tolerance of the active sites of these enzymes is of considerable practical interest. We have determined the crystal structure at 2.1 Å resolution of Lactobacillus helveticus purine deoxyribosyl transferase (PDT with the tricyclic purine 8,9-dihydro-9-oxoimidazo[2,1-b]purine (N2,3-ethenoguanine at the active site. The active site electron density map was compatible with four orientations, two consistent with sites for deoxyribosylation and two appearing to be unproductive. In accord with the crystal structure, Lactobacillus helveticus PDT glycosylates the 8,9-dihydro-9-oxoimidazo[2,1-b]purine at N7 and N1, with a marked preference for N7. The activity of Lactobacillus helveticus PDT was compared with that of the nucleoside 2'-deoxyribosyltransferase enzymes (DRT Type II from Lactobacillus leichmannii and Lactobacillus fermentum, which were somewhat more effective in the deoxyribosylation than Lactobacillus helveticus PDT, glycosylating the substrate with product profiles dependent on the pH of the incubation. The purine nucleoside phosphorylase of Escherichia coli, also commonly used in ribosylation of non-natural bases, was an order of magnitude less efficient than the transferase enzymes. Modeling based on published active-site structures as templates suggests that in all cases, an active site Phe is critical in orienting the molecular plane of the purine derivative. Adventitious hydrogen bonding with additional active site residues appears to result in presentation of multiple nucleophilic sites on the periphery of the acceptor base for ribosylation to give a distribution of nucleosides. Chemical glycosylation of O9-benzylated 8,9-dihydro-9-oxoimidazo[2,1-b]purine also resulted

  3. The Effect of Ag Content of the Chitosan-Silver Nanoparticle Composite Material on the Structure and Antibacterial Activity

    OpenAIRE

    Solmaz Akmaz; Esra Dilaver Adıgüzel; Muzaffer Yasar; Oray Erguven

    2013-01-01

    The aim of this study is to investigate the antibacterial properties and characterization of chitosan-silver nanoparticle composite materials. Chitosan-silver nanoparticle composite material was synthesized by adding AgNO3 and NaOH solutions to chitosan solution at 95°C. Different concentrations (0,02 M, 0,04 M, and 0,06 M) of AgNO3 were used for synthesis. Chitosan-silver nanoparticle composite materials were characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), u...

  4. Antibacterial Resistance in African Catfish Aquaculture: a Review

    Directory of Open Access Journals (Sweden)

    Madubuike U. ANYANWU

    2016-03-01

    Full Text Available Antibacterial resistance (AR is currently one of the greatest threats to mankind as it constitutes health crisis. Extensive use of antibacterial agents in human and veterinary medicine, and farm crops have resulted in emergence of antibacterial-resistant organisms in different environmental settings including aquaculture. Antibacterial resistance in aquaculture is a serious global concern because antibacterial resistance genes (ARGs can be transferred easily from aquaculture setting to other ecosystems and the food chain. African catfish (ACF aquaculture has increased at a phenomenal rate through a continuous process of intensification, expansion and diversification. Risk of bacterial diseases has also increased and consequently there is increased use of antibacterial agents for treatment. Antibacterial resistance in ACF aquaculture has huge impact on the food chain and thus represents risk to public and animal health. In “one health” approach of curbing AR, knowledge of the sources, mechanisms and magnitude of AR in ACF aquaculture and its potential impact on the food chain is important in designing and prioritizing monitoring programs that may generate data that would be relevant for performing quantitative risk assessments, implementation of antibacterial stewardship plans, and developing effective treatment strategies for the control of ACF disease and reducing risk to public health. This review provides insight on the sources, mechanisms, prevalence and impact of antibacterial resistance in ACF aquaculture environment, a setting where the impact of AR is neglected or underestimated.

  5. Effect of NaOH concentration on structural, surface and antibacterial activity of CuO nanorods synthesized by direct sonochemical method

    Science.gov (United States)

    Sonia, S.; Jayram, Naidu Dhanpal; Suresh Kumar, P.; Mangalaraj, D.; Ponpandian, N.; Viswanathan, C.

    2014-02-01

    Highly efficient Copper oxide (CuO) nanorods were synthesized by using one step sonochemical method under room temperature with change in NaOH concentration. XRD confirms the prepared nanorods are in pure monoclinic phase with lattice constants a = 4.68 Å, b = 3.42 Å, and c = 5.13 Å and FESEM analysis reveals an average diameter of 50-100 nm. Optical absorption spectra exhibits the strong blue shift compared with bulk and the bandgap increases with decreasing the size of the nanorods which is due to the nanosize effect. The composition of CuO nanorods were characterized by Fourier Transform Infra-Red spectroscopy (FTIR) which confirms the formation of monoclinic phase of CuO and the Thermal analysis was done by Thermo Gravimetric Analysis (TGA). The antibacterial properties of copper oxide nanorods were investigated using human pathogens and was compared based on diameter of inhibition zone using agar well diffusion method. The synthesized copper oxide nanostructures show excellent antibacterial activity against Salmonella typhimurium than Staphylococcus aureus strain.

  6. Green synthesis and antibacterial effects of aqueous colloidal solutions of silver nanoparticles using camomile terpenoids as a combined reducing and capping agent.

    Science.gov (United States)

    Parlinska-Wojtan, Magdalena; Kus-Liskiewicz, Małgorzata; Depciuch, Joanna; Sadik, Omowunmi

    2016-08-01

    Green synthesis method using camomile extract was applied to synthesize silver nanoparticles to tune their antibacterial properties merging the synergistic effect of camomile and Ag. Scanning transmission electron microscopy revealed that camomile extract (CE) consisted of porous globular nanometer sized structures, which were a perfect support for Ag nanoparticles. The Ag nanoparticles synthesized with the camomile extract (AgNPs/CE) of 7 nm average sizes, were uniformly distributed on the CE support, contrary to the pure Ag nanoparticles synthesized with glucose (AgNPs/G), which were over 50 nm in diameter and strongly agglomerated. The energy dispersive X-ray spectroscopy chemical analysis showed that camomile terpenoids act as a capping and reducing agent being adsorbed on the surface of AgNPs/CE enabling their reduction from Ag(+) and preventing them from agglomeration. Fourier transform infrared and ultraviolet-visible spectroscopy measurements confirmed these findings, as the spectra of AgNPs/CE, compared to pure CE, did not contain the 1109 cm(-1) band, corresponding to -C-O groups of terpenoids and the peaks at 280 and 320 nm, respectively. Antibacterial tests using four bacteria strains showed that the AgNPs/CE performed five times better compared to CE AgNPs/G samples, reducing totally all the bacteria in 2 h.

  7. Core–shell magnetic nanoparticles display synergistic antibacterial effects against Pseudomonas aeruginosa and Staphylococcus aureus when combined with cathelicidin LL-37 or selected ceragenins

    Science.gov (United States)

    Niemirowicz, Katarzyna; Piktel, Ewelina; Wilczewska, Agnieszka Z; Markiewicz, Karolina H; Durnaś, Bonita; Wątek, Marzena; Puszkarz, Irena; Wróblewska, Marta; Niklińska, Wiesława; Savage, Paul B; Bucki, Robert

    2016-01-01

    Core–shell magnetic nanoparticles (MNPs) are promising candidates in the development of new treatment methods against infections, including those caused by antibiotic-resistant pathogens. In this study, the bactericidal activity of human antibacterial peptide cathelicidin LL-37, synthetic ceragenins CSA-13 and CSA-131, and classical antibiotics vancomycin and colistin, against methicillin-resistant Staphylococcus aureus Xen 30 and Pseudomonas aeruginosa Xen 5, was assessed alone and in combination with core–shell MNPs. Fractional inhibitory concentration index and fractional bactericidal concentration index were determined by microdilution methods. The potential of combined therapy using nanomaterials and selected antibiotics was confirmed using chemiluminescence measurements. Additionally, the ability of tested agents to prevent bacterial biofilm formation was evaluated using crystal violet staining. In most conditions, synergistic or additive effects were observed when combinations of core–shell MNPs with ceragenins or classical antibiotics were used. Our study revealed that a mixture of membrane-active agents such as LL-37 peptide or ceragenin CSA-13 with MNPs potentialized their antibacterial properties and might be considered as a method of delaying and overcoming bacterial drug resistance. PMID:27799768

  8. Nucleoside analogue therapy following one-year course of hepatitis B immunoglobulin in preventing hepatitis B virus reactivation after living donor liver transplantation.

    Science.gov (United States)

    Kawagishi, Naoki; Takeda, Ikuo; Miyagi, Shigehito; Satoh, Kazushige; Akamatsu, Yorihiro; Sekiguchi, Satoshi; Satomi, Susumu

    2010-12-01

    The combination therapy with hepatitis B immunoglobulin (HBIG) and nucleoside analogue is well tolerated for the hepatitis B recipients after liver transplantation, but its cost is an important problem in these days. Here we report the efficacy of nucleoside analogue therapy following one-year course of HBIG plus nucleoside analogue after living donor liver transplantation (LDLT). Out of 103 LDLTs, we selected 14 recipients who received the post-transplant therapy against reactivation of hepatitis B virus for more than 30 months. Those were eight patients with chronic hepatitis B, three with fulminant hepatitis, and three whose donors were positive for antibody to HB core antigen (HBc). During two days after the operation, HBIG (40,000 units) was administered, and the serum level of antibody to HB surface antigen (HBs) was maintained at around 150 IU/L for one year by monthly administration of HBIG. After one year, HBIG was withdrawn. A nucleoside analogue was administered daily from just after LDLT, and it was continued up to the present. Among the 14 patients, two recipients had recurrence of hepatitis B. Three patients, including one patient with recurrence of hepatitis B, died due to hepatocellular carcinoma or its associated cirrhosis; namely, their deaths are unrelated to hepatitis B-related diseases. The remaining 11 patients are leading normal lives. In conclusion, nucleoside analogue therapy after one-year course of HBIG plus nucleoside analogue is feasible and cost-effective in preventing HBV reactivation. But the patients are still at risk of breakthrough and some patients may need continued prophylaxis with HBIG.

  9. Mildiomycin: a nucleoside antibiotic that inhibits protein synthesis.

    Science.gov (United States)

    Feduchi, E; Cosín, M; Carrasco, L

    1985-03-01

    Mildiomycin, a new nucleoside antibiotic, selectively inhibits protein synthesis in HeLa cells, and is less active in the inhibition of RNA or DNA synthesis. An increased inhibition of translation by mildiomycin is observed in cultured HeLa cells when they are permeabilized by encephalomyocarditis virus. This observation suggests that this antibiotic does not easily pass through the cell membrane, as occurs with other nucleoside and aminoglycoside antibiotics. The inhibition of translation is also observed in cell-free systems, such as endogenous protein synthesis in a rabbit reticulocyte lysate or the synthesis of polyphenylalanine directed by poly (U). Finally the mode of action of mildiomycin was investigated and the results suggest that the compound blocks the peptidyl-transferase center.

  10. Modified Nucleoside Triphosphates for in-vitro Selection Techniques

    Science.gov (United States)

    Iribarren, Adolfo; Dellafiore, María; Montserrat, Javier

    2016-05-01

    The development of SELEX (Selective Enhancement of Ligands by Exponential Enrichment) provides a powerful tool for the search of functional oligonucleotides with the ability to bind ligands with high affinity and selectivity (aptamers) and for the discovery of nucleic acid sequences with diverse enzymatic activities (ribozymes and DNAzymes). This technique has been extensively applied to the selection of natural DNA or RNA molecules but, in order to improve chemical and structural diversity as well as for particular applications where further chemical or biological stability is necessary, the extension of this strategy to modified oligonucleotides is desirable. Taking into account these needs, this review intends to collect the research carried out during the past years, focusing mainly on the use of modified nucleotides in SELEX and the development of mutant enzymes for broadening nucleoside triphosphates acceptance. In addition, comments regarding the synthesis of modified nucleoside triphosphate will be briefly discussed.

  11. Virological efficacy of combination therapy with corticosteroid and nucleoside analogue for severe acute exacerbation of chronic hepatitis B.

    Science.gov (United States)

    Yasui, S; Fujiwara, K; Nakamura, M; Miyamura, T; Yonemitsu, Y; Mikata, R; Arai, M; Kanda, T; Imazeki, F; Oda, S; Yokosuka, O

    2015-02-01

    The short-term prognosis of patients with severe acute exacerbation of chronic hepatitis B (CHB) leading to acute liver failure is extremely poor. We have reported the efficacy of corticosteroid in combination with nucleoside analogue in the early stages, but virological efficacy has not been documented. Our aim was to elucidate the virological efficacy of this approach. Thirteen patients defined as severe acute exacerbation of CHB by our uniform criteria were prospectively examined for virological responses to treatment. Nucleoside analogue and sufficient dose of corticosteroids were introduced as soon as possible after the diagnosis of severe disease. Of the 13 patients, 7 (54%) survived, 5 (38%) died and 1 (8%) received liver transplantation. The decline of HBV DNA was significant between the first 2 weeks (P = 0.02) and 4 weeks (P analogue has sufficient virological effect against severe acute exacerbation of CHB, and a rapid decline of HBV DNA is conspicuous in survived patients.

  12. Evaluation of anti-HIV-1 mutagenic nucleoside analogues.

    Science.gov (United States)

    Vivet-Boudou, Valérie; Isel, Catherine; El Safadi, Yazan; Smyth, Redmond P; Laumond, Géraldine; Moog, Christiane; Paillart, Jean-Christophe; Marquet, Roland

    2015-01-02

    Because of their high mutation rates, RNA viruses and retroviruses replicate close to the threshold of viability. Their existence as quasi-species has pioneered the concept of "lethal mutagenesis" that prompted us to synthesize pyrimidine nucleoside analogues with antiviral activity in cell culture consistent with an accumulation of deleterious mutations in the HIV-1 genome. However, testing all potentially mutagenic compounds in cell-based assays is tedious and costly. Here, we describe two simple in vitro biophysical/biochemical assays that allow prediction of the mutagenic potential of deoxyribonucleoside analogues. The first assay compares the thermal stabilities of matched and mismatched base pairs in DNA duplexes containing or not the nucleoside analogues as follows. A promising candidate should display a small destabilization of the matched base pair compared with the natural nucleoside and the smallest gap possible between the stabilities of the matched and mismatched base pairs. From this assay, we predicted that two of our compounds, 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine, should be mutagenic. The second in vitro reverse transcription assay assesses DNA synthesis opposite nucleoside analogues inserted into a template strand and subsequent extension of the newly synthesized base pairs. Once again, only 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine are predicted to be efficient mutagens. The predictive potential of our fast and easy first line screens was confirmed by detailed analysis of the mutation spectrum induced by the compounds in cell culture because only compounds 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine were found to increase the mutation frequency by 3.1- and 3.4-fold, respectively.

  13. Purine nucleoside phosphorylase deficiency in two unrelated Saudi patients

    OpenAIRE

    Alangari, Abdullah; Al-Harbi, Abdullah; Al-Ghonaium, Abdulaziz; Santisteban, Ines; Hershfield, Michael

    2009-01-01

    Purine nucleoside phosphorylase (PNP) deficiency is a rare autosomal recessive metabolic disorder that results in combined immunodeficiency, neurologic dysfunction and autoimmunity. PNP deficiency has never been reported from Saudi Arabia or in patients with an Arabic ethnic background. We report on two Saudi girls with PNP deficiency. Both showed severe lymphopenia and neurological involvement. Sequencing of the PNP gene of one girl revealed a novel missense mutation Pro146>Leu in exon 4 due...

  14. 竹醋液在净味抗菌内墙乳胶漆中的应用%The Application of Bamboo Vinegar in Interior Latex Paint with Clean Taste and Antibacterial Effect

    Institute of Scientific and Technical Information of China (English)

    肖劲; 胡中源; 王德华

    2012-01-01

    介绍了一种新型的净味抗菌内墙乳胶漆,精选纯天然竹醋液,采用中空聚合物包埋,延缓了天然竹醋液的挥发。保证了长期的抗菌作用。%A new interior latex paint with clean taste and antibacterial effect was introduced. The latex paint was possessed of long antibacterial activity by selection of natural bamboo vinegar and embedding with hollow polymer as to delay the evaporation of natural bamboo vinegar.

  15. Nucleobase and nucleoside transport and integration into plant metabolism

    Directory of Open Access Journals (Sweden)

    Christopher eGirke

    2014-09-01

    Full Text Available Nucleotide metabolism is an essential process in all living organisms. Besides newly synthesized nucleotides, the recycling (salvage of partially degraded nucleotides i.e. nucleosides and nucleobases serves to keep the homeostasis of the nucleotide pool. Both types of metabolites are substrates of at least six families of transport proteins in Arabidopsis thaliana (Arabidopsis with a total of 49 members. In the last years several members of such transport proteins have been analyzed allowing to present a more detailed picture of nucleoside and nucleobase transport and the physiological function of these processes. Besides functioning in nucleotide metabolism it turned out that individual members of the before named transporters exhibit the capacity to transport a wide range of different substrates including vitamins and phytohormones. The aim of this review is to summarize the current knowledge on nucleobase and nucleoside transport processes in plants and integrate this into nucleotide metabolism in general. Thereby, we will focus on those proteins which have been characterized at the biochemical level.

  16. Nucleobase and nucleoside transport and integration into plant metabolism.

    Science.gov (United States)

    Girke, Christopher; Daumann, Manuel; Niopek-Witz, Sandra; Möhlmann, Torsten

    2014-01-01

    Nucleotide metabolism is an essential process in all living organisms. Besides newly synthesized nucleotides, the recycling (salvage) of partially degraded nucleotides, i.e., nucleosides and nucleobases serves to keep the homeostasis of the nucleotide pool. Both types of metabolites are substrates of at least six families of transport proteins in Arabidopsis thaliana (Arabidopsis) with a total of 49 members. In the last years several members of such transport proteins have been analyzed allowing to present a more detailed picture of nucleoside and nucleobase transport and the physiological function of these processes. Besides functioning in nucleotide metabolism it turned out that individual members of the before named transporters exhibit the capacity to transport a wide range of different substrates including vitamins and phytohormones. The aim of this review is to summarize the current knowledge on nucleobase and nucleoside transport processes in plants and integrate this into nucleotide metabolism in general. Thereby, we will focus on those proteins which have been characterized at the biochemical level.

  17. A Study of the Antibacterial Activity of Polyhexamethylene Bigaunide on Cotton Substrate

    NARCIS (Netherlands)

    Amrit, U.R.; Hendrix, R.; Dutschk, V.; Warmoeskerken, M.M.C.G.; Mijovic, Budimir; Ujevic, Darko; Petrak, Slavenka; Grancaric, Marija Ana; Glogar, Ira Martinia; Salopek Cubric, Ivana

    2012-01-01

    Interest in antibacterial textiles has been increasing recently. Different kinds of antibacterial textiles with different effectivity are being sold in the market. The influence of time on the antibacterial activity of such textiles is not known generally. The goal of this research was to study the

  18. Comparison of the Antibacterial Effect of Sodium Hypochlorite and Aloe Vera Solutions as Root Canal Irrigants in Human Extracted Teeth Contaminated with Enterococcus Faecalis

    Directory of Open Access Journals (Sweden)

    Sahebi S.

    2013-10-01

    Full Text Available Statement of Problem: The main purpose of a root canal treatment is to eliminate the bacteria and their products from the pulp space. Sodium hypochlorite has excellent antibacterial properties, but also some negative features. Purpose: The aim of the present study is to compare the antimicrobial effect of Aloe Vera so-lution with sodium hypochlorite on E.faecalis in the root canals of human extracted teeth. Materials and Method: Sixty human extracted single rooted teeth were selected for this in vitro study. The teeth recruited in this study had no cracks, internal resorption, external resorption and calcification. Enterococcus faecalis was injected in the root canals of all teeth. The teeth were then divided into three groups randomly. Each group consisted of 20 teeth that were all rinsed with one of the following solutions: sodium hypochlorite 2.5%, Aloe vera and normal saline. Subsequent to rinsing, root canals of all teeth were sampled. The samples were cultured and growth of the bacteria was assessed after 48 hours. The number of colonies of the bacteria was then counted. Results: The difference between the inhibitory effect of Aloe vera and normal saline on E.faecalis was not significant according to independent t-test (p= 0.966. The inhibitory effect of sodium hypochlorite on E.faecalis was much greater than that of Aloe vera and normal saline (p< 0.001. Conclusion: Aloe vera solution is not recommended as a root canal irrigator, but future studies are suggested to investigate the antibacterial effect of Aloe vera with longer duration of exposure and as an intra canal medicament.

  19. Comparison of the Antibacterial Effect of Sodium Hypochlorite and Aloe Vera Solutions as Root Canal Irrigants in Human Extracted Teeth Contaminated with Enterococcus Faecalis

    Directory of Open Access Journals (Sweden)

    Sahebi S.

    2014-03-01

    Full Text Available Statement of Problem: The main purpose of a root canal treatment is to eliminate the bacteria and their products from the pulp space. Sodium hypochlorite has excellent antibacterial properties but also some negative features. Purpose: The aim of the present study is to compare the antimicrobial effect of Aloe Vera solution with sodium hypochlorite on E.faecalis in the root canals of human extracted teeth. Materials and Method: Sixty human extracted single rooted teeth were selected for this in vitro study. Only teeth without conditions such as cracks, internal resorption, external resorption and calcification were included in the study. Enterococcus faecalis was injected in the root canals of all teeth. The teeth were then divided into three groups randomly. Each group consisted of 20 teeth that were all rinsed with one of the following solutions: sodium hypochlorite 2.5%, Aloe vera and normal saline. Subse-quent to rinsing, root canals of all teeth were sampled. The samples were cultured and growth of the bacteria was assessed after 48 hours. The number colonies of the bacte-ria were then counted. Results: The difference between the inhibitory effect of Aloe vera and normal saline on E.faecalis was not significant according to independent T-test (p= 0.966. The in-hibitory effect of sodium hypoch