Loading...
Search for:
antimicrobial-activity
0.007 seconds
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Maghsoudi, Vida (Supervisor)
Abstract
This practice investigates about the resistance & sustainability of a sample of available microorganisms in fruit juices vs. a natural anti microbe called vanillin. To be more precisely the anti bacterial characteristic of vanillin has been tested against famous pathogenic organism Escherichia Coli in apple juice. The practice has been experienced for different concentrations of Vanillin, controlling & reducing the microbe concentration in apple synthetic juice. The effect has been investigated by measuring sensitivity of results in two different temperatures one in 8 degree of centigrade & other in 15, in each temperature two PH have been tested (PH = 3.5 & 4.5) 0-40-80 m-molar as 3...
Synthesis and Characterization of Silver/Poly (Lactic Acid) Nanocomposite and Effect of Gamma Ray
, M.Sc. Thesis Sharif University of Technology ; Forounchi, Massoud (Supervisor) ; Dadbin, Susan (Supervisor)
Abstract
Nanocomposites of PLA/Ag, PLA/PEG/Ag and PLA/PEG/Oleic acid were synthesized via chemical reduction of AgNO3.The formation of nano-silver particles (Ag-NPs) started in the aqueous phase (using NaBH4 as a reducing agent) followed by transfer of the silver nanoparticles into the organic phase (PLA solution in chloroform) due to the presence of van der waals interactions between the hydroxyl groups of the PLA and the particles charges surrounded in the surface of the Ag-NPs. The nanocomposites films were prepared by the solution casting method. The XRD patterns and UV-Vis spectra of the nanocomposites demonstrated face–centered cubic (fcc) silver crystals and spherical nanoparticles...
Investigation of the Antibacterial Property of TiO2/Ag Nanotubes
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Bagheri, Reza (Supervisor)
Abstract
This study was performed to synthesize Ag-doped TiO2 nanotubes and investigate the antibacterial property of the nanostructure. In the first step, self-organized TiO2 nanotubes were fabricated through anodizing in an electrolyte containing 0٫3 Wt% NH4F, 0٫2٪V DI water and ethylene glycol. Anodizing was performed in 30 and 60V for 2hrs in order to have different nanotube diameters. In the second step, photoreduction process was done on the way to dope Ag nanoparticles on the nanotubes. Herein, AgNO3 solution concentration, time period of TiO2 nanotubes soaking in the solution, time period of UV irradiation and ethanol solution concentration were taken as factors to achieve Ag nanoparticles in...
Bioactive Packaging Study to Improve the Quality of Food Products
, M.Sc. Thesis Sharif University of Technology ; Roostaazad, Reza (Supervisor)
Abstract
One of the most important concerns in food industry is decreasing the contamination of food and increasing their shelf life. Antimicrobial/antioxidant packaging, an active packaging concept, can be considered an extremely challenging technology that could have a significant impact on shelf-life extension and food safety of meat and meat products. Due to harmfulness of chemical preservatives, their use has been limited and therefore natural antimicrobial/antioxidant agents have become more popular. Propolis is a natural resinous substance, with a high polyphenol content, produced by honeybees and characterized by antimicrobial, anti-inflammatory and antioxidant properties, which make it...
Biodegradation of synthetic dye using partially purified and characterized laccase and its proposed mechanism
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 12 , 2019 , Pages 7805-7816 ; 17351472 (ISSN) ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
The supernatant obtained from the extracellular laccase produced by Phanerochaete chrysosporium was used as the enzyme source to conduct a partial purification, characterization and dye decolorization study. The partially purified enzyme was stable in the pH range of 3–5 and showed an optimum activity at pH 4.0, using guaiacol as a substrate. Laccase stability of pH was determined and discovered to retain 100% of its activity at a pH of 4.0 after 2 h. The maximum enzyme activity was obtained between 30 and 50 °C. The maximum velocity and Michaelis constant were calculated as 3.171 µM−1·min and 1628.23 µM, respectively. The enzyme was activated by Fe2+, Zn2+, Ca2+ and Cu2+, while Hg2+, Mn2+,...
Ferric metformin drug complex supported on magnetic nanofiber cellulose; An efficient access to 4-H pyrans derivatives and determination of their antimicrobial activity
, Article Synthetic Communications ; Volume 52, Issue 7 , 2022 , Pages 974-993 ; 00397911 (ISSN) ; Daneshfar, M ; Moghimi, H ; Daneshfar, Z ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Magnetic nanofiber cellulose (NFC) was selected as a biopolymer surface for the reaction with ferric metformin and a novel nanocatalyst was prepared. This green heterogeneous organometallic catalyst was analyzed by physiochemical techniques. The new metformin drug complex supported on magnetic NFC was used as a powerful and efficient catalyst for the synthesis of functionalized 4H-pyrans derivatives. The antimicrobial activity of the products showed excellent activity against all the bacterial and fungal strains (especially compounds 7q and 6r). © 2022 Taylor & Francis Group, LLC
Effect of Cu2+ ion on biological performance of nanostructured uorapatite doped with copper
, Article Scientia Iranica ; Volume 24, Issue 6 , 2017 , Pages 2845-2855 ; 10263098 (ISSN) ; Sadrnezhaad, S. K ; Vahdati Khaki, J ; Sharif University of Technology
Abstract
Nanostructured copper-doped uorapatite (Cux.Ca(10X).(PO4)6.F2) having crystallite sizes of 19, 29, and 34 nm at x = 0:9, 0.4, and 0.0, respectively, was synthesized by planetary ball milling of CaO, P2O5, CaF2, and CuO powders. Specifications of the products were determined by Fourier-transform infrared spectroscopy, eld emission scanning electron microscopy, transmission electron microscopy, and X-ray di raction analyses. In-vitro studies and Mossman's Tetrazole Test (MTT) assays were also conducted by incubating Cux.Ca(10X).(PO6).F2 powder into Kokubo's Simulated Body Fluid (SBF) and against BT-20 cell, respectively, to determine bioactivity and biocompatibility of the materials....
A comparative study of wound dressings loaded with silver sulfadiazine and silver nanoparticles: In vitro and in vivo evaluation
, Article International Journal of Pharmaceutics ; Volume 564 , 2019 , Pages 350-358 ; 03785173 (ISSN) ; Shamloo, A ; Aghababaie, Z ; Afjoul, H ; Abdi, S ; Moravvej, H ; Vossoughi, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In the current study, two series of antimicrobial dressings conjugated with silver sulfadiazine (SSD) and silver nanoparticles (AgNPs) were developed and evaluated for chronic wound healing. Highly porous polycaprolactone (PCL)/polyvinyl alcohol (PVA) nanofibers were loaded with different concentrations of SSD or AgNPs and compared comprehensively in vitro and in vivo. SSD and AgNPs indicated a strong and equal antimicrobial activity against S. aureus. However, SSD had more toxicity against fibroblast cells over one week in vitro culture. An in vivo model of wound healing on male Wistar rats was developed with a full thickness wound. All the wound dressings indicated enough flexibility and...
Ag-doped magnetic metal organic framework as a novel nanostructured material for highly efficient antibacterial activity
, Article Environmental Research ; Volume 188 , 2020 ; Abdi, J ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
Academic Press Inc
2020
Abstract
In the last decades, numerous attempts have been made to prevent microbial pollution spreading, using antibacterial agents. Zeolitic imidazolate framework-8 (ZIF-8) belongs to a subgroup of metal organic frameworks (MOFs) merits of attention due to the zinc ion clusters and its effective antibacterial activity. In this work, Ag-doped magnetic microporous γ-Fe2O3@SiO2@ZIF-8-Ag (FSZ-Ag) was successfully synthesized by a facile methodology in room temperature and used as an antibacterial agent against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. Several characterization methods were applied to analyze the properties of the materials, and the...
Optimization, physicochemical characterization, and antimicrobial activity of a novel simvastatin nano-niosomal gel against E. coli and S. aureus
, Article Chemistry and Physics of Lipids ; Volume 234 , 2021 ; 00093084 (ISSN) ; Keramati, M ; Azadi, A ; Afzali, E ; Shahbazi, R ; chiani, M ; Norouzian, D ; Bakhshandeh, H ; Sharif University of Technology
Elsevier Ireland Ltd
2021
Abstract
Niosomes, as a kind of drug delivery system, is widely used for the topical delivery of lipophilic drugs. Optimization of niosomes plays an essential role in enhancing their therapeutic efficiencies. This study aims to prepare an optimized niosomal formulation of simvastatin (nSIM), a lipophilic member of statins, through the experiment (Response Surface methodology). Optimized niosomes were characterized in size, polydispersity index (PDI), entrapment efficiency (EE), stability, releasing pattern, and antimicrobial activity. The different molar ratio of surfactant and cholesterol were applied to prepare various formulation of simvastatin loaded niosome. Mean particle size and size...
Optimization, physicochemical characterization, and antimicrobial activity of a novel simvastatin nano-niosomal gel against E. coli and S. aureus
, Article Chemistry and Physics of Lipids ; Volume 234 , 2021 ; 00093084 (ISSN) ; Keramati, M ; Azadi, A ; Afzali, E ; Shahbazi, R ; chiani, M ; Norouzian, D ; Bakhshandeh, H ; Sharif University of Technology
Elsevier Ireland Ltd
2021
Abstract
Niosomes, as a kind of drug delivery system, is widely used for the topical delivery of lipophilic drugs. Optimization of niosomes plays an essential role in enhancing their therapeutic efficiencies. This study aims to prepare an optimized niosomal formulation of simvastatin (nSIM), a lipophilic member of statins, through the experiment (Response Surface methodology). Optimized niosomes were characterized in size, polydispersity index (PDI), entrapment efficiency (EE), stability, releasing pattern, and antimicrobial activity. The different molar ratio of surfactant and cholesterol were applied to prepare various formulation of simvastatin loaded niosome. Mean particle size and size...
A state-of-the-art review of the fabrication and characteristics of titanium and its alloys for biomedical applications
, Article Bio-Design and Manufacturing ; Volume 5, Issue 2 , 2022 , Pages 371-395 ; 20965524 (ISSN) ; Rezvani Ghomi, E ; Alipour, S ; Ramakrishna, S ; Liana Sukiman, N ; Sharif University of Technology
Springer
2022
Abstract
Abstract: Commercially pure titanium and titanium alloys have been among the most commonly used materials for biomedical applications since the 1950s. Due to the excellent mechanical tribological properties, corrosion resistance, biocompatibility, and antibacterial properties of titanium, it is getting much attention as a biomaterial for implants. Furthermore, titanium promotes osseointegration without any additional adhesives by physically bonding with the living bone at the implant site. These properties are crucial for producing high-strength metallic alloys for biomedical applications. Titanium alloys are manufactured into the three types of α, β, and α + β. The scientific and clinical...