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Food security is very important in all processes executed for the manufacture of meat in meatpacking industries. Meat security can be improved by the use of accessories produced with antimicrobial materials in the manufacture line...
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Food security is very important in all processes executed for the manufacture of meat in meatpacking industries. Meat security can be improved by the use of accessories produced with antimicrobial materials in the manufacture lines. In this work, the antibacterial property was incorporated in the plates of polyamide 6 by the addition of two antibacterial compounds and the antimicrobial characteristics were studied. The antibacterial materials used were glass microparticles doped with ionic zinc and zinc oxide nanoparticles. The antibacterial polyamide 6 was produced containing different percentages of antibacterial compound and its microbiological characterization was realized with the bacteria Salmonella typhimurium and Staphylococcus aureus. The distribution of the antimicrobial compound in polyamide 6 matrix was evaluated by scanning electron microscopy and energy dispersive spectroscopy. Atomic absorption spectrometry was applied to study the migration capacity of the antibacterial compound in the aqueous medium. The results demonstrated that the polyamide 6 containing glass microparticles doped with ionic zinc present better antibacterial action than the polyamide 6 containing zinc oxide nanoparticles. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45005.
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Clove oil has many functions such as antibacterial, anti-inflammatory, anti-oxidation. In this experiment, a self-emulsification method was used to prepare clove oil nanoemulsion. And then filter paper diffusion method, minimum in...
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Clove oil has many functions such as antibacterial, anti-inflammatory, anti-oxidation. In this experiment, a self-emulsification method was used to prepare clove oil nanoemulsion. And then filter paper diffusion method, minimum inhibitory concentration, and minimum bactericidal concentration were used to study the inhibitory behavior of clove oil nanoemulsion on Escherichia coli and Staphylococcus aureus. And explore the antibacterial mechanism by dynamically testing the content of nucleic acid and protein in the culture solution during the antibacterial process. The results show that when the surfactant content is 10 wt%, the hydrophile-lipophile balance (HLB) is 13.93, and the oil phase content is 2 wt%, a clove oil nanoemulsion with better dispersion and smaller average particle size can be prepared. The minimum inhibitory concentration (MIC) of clove oil nanoemulsion against Escherichia coli and Staphylococcus aureus is 0.5, 0.25 mg/mL, and the minimum bactericidal concentration (MBC) is 1, 2 mg/mL. The increase in protein content and the exponential growth of nucleic acid release also indicated that the clove oil nanoemulsion destroys the integrity of the cell membrane. The experimental results can provide a reference for the application of clove oil nanoemulsion in food, medicine and other fields. [GRAPHICS] .
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The antibacterial activity of phillyrin on Escherichia coli ATCC8739 (E. coli ATCC8739),Bacillus subtilis BS08,Staphylococcus aureus ATCC6538 (S. aureus ATCC6538) and Salmonella ATCC14028 was determined by filter paper method. The...
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The antibacterial activity of phillyrin on Escherichia coli ATCC8739 (E. coli ATCC8739),Bacillus subtilis BS08,Staphylococcus aureus ATCC6538 (S. aureus ATCC6538) and Salmonella ATCC14028 was determined by filter paper method. The minimum inhibitory concentration (MIC) of the four tested bacteria was investigated by plate coating method to evaluate antibacterial ability. The antibacterial mechanism was further investigated by measuring growth curve,electric conductivity,nucleic acid content,Na+/K+-ATPase activity and polyacrylamide gel electrophoresis (SDS-PAGE). The results indicated that phillyrin had antibacterial effects and the MICs against Escherichia coli ATCC8739,Bacillus subtilis BS08,Staphylococcus aureus ATCC6538 and Salmonella ATCC14028 were 2.15,3.16,3.02 and 3.40 μg/mL respectively,and the antibacterial effect on Escherichia coli ATCC 8739 was more significant (p< 0.05) than that on other bacteria. Scanning electron microscopy (SEM) indicated that phillyrin destroyed the morphology of the cells and the cells ruptured. The leakage of intracellular substances led to an increase in nucleic acid content and an increase in electric conductivity in the bacterial suspension; SDS-PAGE analysis indicated that phillyrin could inhibit protein synthesis; in addition,phillyrin could reduce Na+/K+-ATPase activity. Therefore,phillyrin had obvious antibacterial ability and inhibited the expression of bacterial proteins by destroying the cell membrane structure,resulting in the death of the cells.
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Antibacterial nanocrystals have attracted great interests in recent years. In fact, with the emergence and increase of microbial organisms resistant to multiple antibiotics, many researchers have tried to develop new antibiotics. ...
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Antibacterial nanocrystals have attracted great interests in recent years. In fact, with the emergence and increase of microbial organisms resistant to multiple antibiotics, many researchers have tried to develop new antibiotics. The aim of this research is to compare antibacterial activity of mono-metallic with composite nanocrystals, againstEscherichia coli,?Salmonella galinarium, Staphylococcus aureus,?Pesudomonas aueroginosa,?and?Bacillus subtilis,?with and without?sonication, for the first time. Mono-metallic with composite nanocrystals, are synthesized via wet method and ensure with oxalate decomposition in high temperature (500°C). FT-IR, XRD, SEM were used for determination of spectroscopic, structural and morphology of samples, respectively. Also the nanoparticls were digested and analyzed by ICP-AES for determining the presence of residual chemical element in the nanoparticles, after sonication. Bacterial sensitivity to nanocrystals, with and without?sonication, were commonly tested using disc diffusion test and agar dilution test, also with determination of minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The particles size was less of 100 nm, approximately. This study shows that synthesis of mono-metallic and composite nanocrystals, with oxalate decomposition method is simple and so useful. Although, we confirmed that utilized of the ultrasonic vibration were futile, entirely. Also, the Ag/ZnO nanocrystals have great antimicrobial agent against all of the strains and?just?combination of zinc oxide and silver?nanocrystals, give increase their bactericidal effect.
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Abstract Background: Candida albicans is a common symbiotic fungus in the oral cavity, which can easily adhere to the surface of implanted materials. Highlighted by a broad antibacterial spectrum and potent antibacterial effects, ...
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Abstract Background: Candida albicans is a common symbiotic fungus in the oral cavity, which can easily adhere to the surface of implanted materials. Highlighted by a broad antibacterial spectrum and potent antibacterial effects, nanosilver-based inorganic antibacterial agents (NSBIAA) are currently being hotly discussed with regard to their influences on biofilm formation of Candida albicans. Purpose: This paper aims to explore the influence of NSBIAA on biofilm formation of Candida albicans. Method: The XTT reduction method and the method of crystal violet determination were applied in measuring the influence of NSBIAA on biofilm formation of Candida albicans. In addition, biofilm morphology was determined by crystal violet staining. Result: It was observed that with the application of liquid antibacterial agent, at a concentration of 0.62 mg/ml, the biofilm activity of Candida albicans reduced (96.1 ± 3.0) %, along with a reduction in the biomass (95.4 ± 2.7) %, and biofilm formation was not observed under an inverted microscope. Conclusion: NSBIAA are able to inhibit biofilm formation.
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The multidrug-resistant bacteria induced infections have become one of the serious threats to global public health. There is an urgent need to fight against bacteria using efficient strategies beyond traditional antibiotics treatm...
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The multidrug-resistant bacteria induced infections have become one of the serious threats to global public health. There is an urgent need to fight against bacteria using efficient strategies beyond traditional antibiotics treatments. As essential trace element, molybdenum (Mo) is an indispensable component of many enzymes in the living body. The relatively low toxicity and unique physicochemical properties of Mo-based nanomaterials make them develop in various biomedical applications especially in antimicrobial stewardship for curing wound infection, sterilizing biomedical equipment, disinfecting water, and so on. In this review, we introduce the synthetic methods, physicochemical properties-related antibacterial activities, and applications of various Mo-based nanomaterials (MoS2, MoOx, molybdates, Mo-based polyoxometalates (POMs), and their hybrids). Then, the main antibacterial strategies including physical contact, photo-induced antibacterial, enzyme-like catalysis, ions release, and synergistic antibacterial are summarized. The antimicrobial mechanisms oriented by antimicrobial strategies are calssified. Furthermore, their inhibition on antimicrobial resistance (AMR) evolution and their biological safety are discussed. Finally, their challenges and prospects to advance the antibacterial activity are also reviewed.
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Antimicrobial hydrogels have been proposed to be interesting materials used for wound healing due to their unique properties. Therefore, numerous scientists have made efforts to design and synthesize antibacterial hydrogels. At pr...
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Antimicrobial hydrogels have been proposed to be interesting materials used for wound healing due to their unique properties. Therefore, numerous scientists have made efforts to design and synthesize antibacterial hydrogels. At present, there are two commonly used methods for preparing antibacterial hydrogels. One is combining antibacterial agents with hydrogels. Antibacterial drugs include antibiotics, some biological extracts, natural polymers and some metal nanoparticles. In this review, physical combination (directly incorporating, swelling diffusion method, encapsulated in carriers) and chemical combination (hydrogels with inherent antibacterial activity, forming chemical bonds) are introduced depending on the methods and types of antibacterial agents incorporated with hydrogels. The other one is light-assisted antibacterial hydrogels, which involve photothermal antibacterial hydrogels and photo-dynamic antibacterial hydrogels. The common methods to prepare light-assisted antibacterial hydrogels are also described in this work. With the rapid improvements in antibacterial technology, many novel antibacterial hydrogels are constantly emerging. The most relevant studies and the latest status of research in this area were evaluated in this review.
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Piperazine polymers poly(ethylenediaminetetraacetic dianhydride-co-piperazine) (PE) and MGF-Ct24E-modified poly(ethylenediaminetetraacetic dianhydride-co-piperazine) (PEM) showed good antibacterial activity. Considering their diff...
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Piperazine polymers poly(ethylenediaminetetraacetic dianhydride-co-piperazine) (PE) and MGF-Ct24E-modified poly(ethylenediaminetetraacetic dianhydride-co-piperazine) (PEM) showed good antibacterial activity. Considering their different applications, the effects of time, pH, and inoculation concentration of these antibacterials against Escherichia coli (E. coli) in unique environments were evaluated in this study. The results indicated that the MIC and MBC values of the polymers increased after the introduction of MGF-Ct24E into PE, but the two types of polymers still exhibited good antibacterial activity in a short time period under acidic conditions. In addition, we investigated the effect of the piperazine polymers on bacterial cell structure. It was clear that PE and PEM could destroy the bacterial cell wall, cell membrane and DNA, and their specific mechanism may be different. For PE, its carboxyl group could react with peptidoglycans on the E.coli cell wall to form holes on the bacterial surface, allowing PE to penetrate into the bacterial cell to damage DNA. For PEM, the alkaline MGF-Ct24E could adsorb E.coli and make it shrink, meanwhile, the PE component created small holes on the bacterial walls and membranes, and inserted into the bacteria to result in bactericidal effect. These findings reveal the potential usefulness of PE and PEM in biomedical applications.
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We synthesized peptide-resin conjugates (1 and 2) by immobilizing (3-sheet antibacterial peptide and a helical antibacterial peptide on PEG-PS resin, respectively. Conjugate 1 showed considerable antibacterial activity in various ...
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We synthesized peptide-resin conjugates (1 and 2) by immobilizing (3-sheet antibacterial peptide and a helical antibacterial peptide on PEG-PS resin, respectively. Conjugate 1 showed considerable antibacterial activity in various conditions, whereas conjugate 2 did not exhibit antibacterial activity. The growths of various bacteria were inhibited by conjugate 1 even at lower concentrations than MIC. Conjugate 1 killed bacteria at MIC and had a potent synergistic effect with current antibacterial agents such as vancomycin and tetracycline, respectively. Overall results indicate that polymer surface modification using antibacterial β sheet peptide is a powerful way to prevent microbial contamination on polymer surfaces.
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