scholarly journals “Characterization, Cytotoxicity, and Genotoxicity Properties of Novel Biomediated Nanosized-Silver By Egyptian Streptomyces Roseolus For Safe Antimicrobial Applications”

2021 ◽  
Author(s):  
Asmaa El Nadi ◽  
Noha Mohamed Sorour ◽  
Rateb Abbas
Keyword(s):  
Antimicrobial Agents ◽  
Antimicrobial Property ◽  
Scale Up ◽  
Klebsiella Pneumonia ◽  
Human Skin Fibroblast ◽  
Ag Nps ◽  
Normal Human Skin ◽  
Blood Lymphocytes ◽  
Vis Spectroscopy ◽  
First Time

Abstract For biosafety purposes, the genotoxicity of biosynthesized silver nanoparticles (Ag-NPs) was assessed using comet assay for the first time on Blood Lymphocytes, with zero tail migration and 100% head intensity indicating non-genotoxic effect. Ag-NPs have been projected as a new generation of antimicrobial agents because of its antimicrobial property. Ag-NPs were biomediated by Egyptian Streptomyces roseolus for the first time, that was molecularly identified using 16S rRNA sequencing under accession no. MT071505. Biosynthesized Ag-NPs were characterized using UV-Vis spectroscopy, XRD, TEM, FTIR, and DLS. FTIR confirmed the presence of different bioactive functional groups, such as, O-H, N-H, C-H, C-O-C, C-NH2, and C=O acting as reducing-stabilizing agents for biosynthesized Ag-NPs. Biosynthesized Ag-NPs exhibited antimicrobial activity against some multi-drug resistant Gram-positive and Gram-negative pathogens. MBC of biosynthesized Ag-NPs against Listeria monocytogenes and Klebsiella pneumonia were 0.195 and 0.048 mg/mL, respectively, with tolerance level of 2 confirming its biocidal effect. SEM imaging of Ag-NPs-treated L. monocytogenes and K. pneumonia showed shrunk destroyed cells after 6h. Biosynthesized Ag-NPs exhibited IC50 of <0.3 and 8.21 mg/mL, respectively, on normal Human Skin Fibroblast, and Blood Lymphocytes. IC50 values were significantly higher than its MBC values, with no harmful cytotoxic-effect, thus can be safely applied at its biocidal concentration. An ecofriendly biomediated synthesis of Ag-NPs was described with easy scale-up, non-toxic by-products, so, it can be recommended as powerful-safe antimicrobial agent.

scholarly journals Silver Nanoparticles: Biosynthesis Using an ATCC Reference Strain ofPseudomonas aeruginosaand Activity as Broad Spectrum Clinical Antibacterial Agents

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Melisa A. Quinteros ◽  
Ivana M. Aiassa Martínez ◽  
Pablo R. Dalmasso ◽  
Paulina L. Páez
Keyword(s):  
Silver Nanoparticles ◽  
Broad Spectrum ◽  
Nitrate Solution ◽  
Human Neutrophils ◽  
Resistant Bacteria ◽  
Klebsiella Pneumonia ◽  
Bacterial Strains ◽  
Ag Nps ◽  
Tem Analysis ◽  
Vis Spectroscopy

Currently, the biosynthesis of silver-based nanomaterials attracts enormous attention owing to the documented antimicrobial properties of these ones. This study reports the extracellular biosynthesis of silver nanoparticles (Ag-NPs) using aPseudomonas aeruginosastrain from a reference culture collection. A greenish culture supernatant ofP. aeruginosaincubated at 37°C with a silver nitrate solution for 24 h changed to a yellowish brown color, indicating the formation of Ag-NPs, which was confirmed by UV-vis spectroscopy, transmission electron microscopy, and X-ray diffraction. TEM analysis showed spherical and pseudospherical nanoparticles with a distributed size mainly between 25 and 45 nm, and the XRD pattern revealed the crystalline nature of Ag-NPs. Also it provides an evaluation of the antimicrobial activity of the biosynthesized Ag-NPs against human pathogenic and opportunistic microorganisms, namely,Staphylococcus aureus,Staphylococcus epidermidis,Enterococcus faecalis,Proteus mirabilis,Acinetobacter baumannii,Escherichia coli,P. aeruginosa, andKlebsiella pneumonia. Ag-NPs were found to be bioactive at picomolar concentration levels showing bactericidal effects against both Gram-positive and Gram-negative bacterial strains. This work demonstrates the first helpful use of biosynthesized Ag-NPs as broad spectrum bactericidal agents for clinical strains of pathogenic multidrug-resistant bacteria such as methicillin-resistantS. aureus,A. baumannii, andE. coli. In addition, these Ag-NPs showed negligible cytotoxic effect in human neutrophils suggesting low toxicity to the host.

scholarly journals Innovative Antimicrobial Chitosan/ZnO/Ag NPs/Citronella Essential Oil Nanocomposite—Potential Coating for Grapes

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1801
Author(s):  
Ludmila Motelica ◽  
Denisa Ficai ◽  
Anton Ficai ◽  
Roxana-Doina Truşcă ◽  
Cornelia-Ioana Ilie ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oil ◽  
Antimicrobial Agents ◽  
Nanocomposite Films ◽  
Vapor Permeability ◽  
Synergic Effect ◽  
Ag Nps ◽  
Fungal Strains ◽  
Control Film ◽  
Vis Spectroscopy

New packaging materials based on biopolymers are gaining increasing attention due to many advantages like biodegradability or existence of renewable sources. Grouping more antimicrobials agents in the same packaging can create a synergic effect, resulting in either a better antimicrobial activity against a wider spectrum of spoilage agents or a lower required quantity of antimicrobials. In the present work, we obtained a biodegradable antimicrobial film that can be used as packaging material for food. Films based on chitosan as biodegradable polymer, with ZnO and Ag nanoparticles as filler/antimicrobial agents were fabricated by a casting method. The nanoparticles were loaded with citronella essential oil (CEO) in order to enhance the antimicrobial activity of the nanocomposite films. The tests made on Gram-positive, Gram-negative, and fungal strains indicated a broad-spectrum antimicrobial activity, with inhibition diameters of over 30 mm for bacterial strains and over 20 mm for fungal strains. The synergic effect was evidenced by comparing the antimicrobial results with chitosan/ZnO/CEO or chitosan/Ag/CEO simple films. According to the literature and our preliminary studies, these formulations are suitable as coating for fruits. The obtained nanocomposite films presented lower water vapor permeability values when compared with the chitosan control film. The samples were characterized by SEM, fluorescence and UV-Vis spectroscopy, FTIR spectroscopy and microscopy, and thermal analysis.

scholarly journals Callus-mediated biosynthesis of Ag and ZnO nanoparticles using aqueous callus extract of Cannabis sativa: Their cytotoxic potential and clinical potential against human pathogenic bacteria and fungi

2021 ◽  
Vol 10 (1) ◽  
pp. 569-584
Author(s):  
Mehreen Zaka ◽  
Syed Salman Hashmi ◽  
Moiz A. Siddiqui ◽  
Lubna Rahman ◽  
Sadaf Mushtaq ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Cannabis Sativa ◽  
Klebsiella Pneumonia ◽  
Bacterial Strains ◽  
Ag Nps ◽  
X Ray ◽  
Synthesis Of Nanoparticles ◽  
Antibacterial And Antifungal Activities ◽  
Vis Spectroscopy ◽  
Bacteria And Fungi

Abstract In this paper, we have presented the method of green synthesis of ZnO and Ag-NPs using the callus extract (CE) of medicinally important Cannabis sativa. The synthesis of nanoparticles (NPs) was confirmed by UV-Vis spectroscopy, while as far as the size and shape of the NPs were concerned, they were validated using the techniques of X-ray diffraction and scanning electron microscopy, respectively. The energy dispersive X-ray analysis graph confirmed the constitution of elements along with the surface chemical state of NPs. Fourier transform-infrared spectroscopy was utilized for the confirmation of biomolecules capping the NPs. In order to test the application of these biosynthesized NPs on biological entities, four bacterial strains, including Bacillus subtilis, Klebsiella pneumonia, Staphylococcus aureus, and Pseudomonas aeruginosa, were used. On the other hand, five fungal strains, namely Mucor, Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, and Fusarium solani, were utilized for antifungal assay. Cytotoxicity assay was also performed using the HepG2 cell line. The results showed considerable antibacterial and antifungal activities. It also showed better cytotoxicity values as compared to the control.

scholarly journals Facile synthesis of Silver nanoparticles with medicinal grass and its biological assessment

2019 ◽  
Author(s):  
Satheeshkumar Balu ◽  
Swetha Andra ◽  
Saranya Kannan ◽  
Manisha vidyavathy S ◽  
Murugesan Muthalagu
Keyword(s):  
Silver Nanoparticles ◽  
Bactericidal Effect ◽  
Inhibitory Effect ◽  
Biological Assessment ◽  
Ag Nps ◽  
E Coli ◽  
Mg63 Cells ◽  
Vis Spectroscopy ◽  
First Time

Biogenic synthesis of silver nanoparticles (SS-Ag NPs) using the extract of Saccharum spontaneum (SS) via green chemistry route was investigated for their in-vitro cytotoxicity on osteoblast-like cells and bactericidal effect. Synthesized SS-Ag NPs were analyzed using TEM, FTIR, XRD and UV Vis spectroscopy techniques. The biomolecules present in S. spontaneum were responsible for the reduction and capping of silver nanoparticles. A heterogenous mixture of SS-Ag NPs which consists of triangle, hexagonal, spherical and rod-like structures was obtained. Furthermore, the synthesized SS-Ag NPs were tested for in a broad spectrum of antibacterial activity against E. coli, S. aureus, K. pneumonia and P. aeruginosa and it showed significant inhibitory effect. For the first time, the enhancement in the proliferation rate of MG63 cells with SS-Ag NPs is reported.

Efficacy of Silver Nanoparticles Synthesized from Hymenocallis species (Spider Lilly) Leaf Extract as Antimicrobial Agents

2019 ◽  
Vol 12 (5) ◽  
pp. 4644-4647
Author(s):  
K.K. Gupta ◽  
Neha Kumari ◽  
Neha Sinha ◽  
Akruti Gupta
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Antimicrobial Agents ◽  
Color Change ◽  
Bacterial Species ◽  
Antimicrobial Property ◽  
Biogenic Synthesis ◽  
E Coli ◽  
Light Yellow ◽  
Antibiotic Property

Biogenic synthesis of silver nanoparticles synthesized from Hymenocallis species (Spider Lilly) leaf extract was subjected for investigation of its antimicrobial property against four bacterial species (E. coli, Salmonella sp., Streptococcus sp. & Staphylococcus sp.). The results revealed that synthesized nanoparticles solution very much justify the color change property from initial light yellow to final reddish brown during the synthesis producing a characteristics absorption peak in the range of 434-466 nm. As antimicrobial agents, their efficacy was evaluated by analysis of variance in between the species and among the different concentration of AgNPs solution, which clearly showed that there was significant variation in the antibiotic property between the four different concentrations of AgNPs solution and also among four different species of bacteria taken under studies. However, silver nanoparticles solution of 1: 9 and 1:4 were proved comparatively more efficient as antimicrobial agents against four species of bacteria.

scholarly journals Green synthesis of silver nanoparticles: Characterization and its potential biomedical applications

2021 ◽  
Vol 10 (1) ◽  
pp. 412-420
Author(s):  
Mona S. Alwhibi ◽  
Dina A. Soliman ◽  
Manal A. Awad ◽  
Asma B. Alangery ◽  
Horiah Al Dehaish ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Aloe Vera ◽  
Inhibition Zone ◽  
Biologically Active ◽  
Noble Metal Nanoparticles ◽  
Biological Synthesis ◽  
Ag Nps ◽  
Mouse Melanoma ◽  
Therapeutic Benefits ◽  
Vis Spectroscopy

Abstract In recent times, research on the synthesis of noble metal nanoparticles (NPs) has developed rapidly and attracted considerable attention. The use of plant extracts is the preferred mode for the biological synthesis of NPs due to the presence of biologically active constituents. Aloe vera is a plant endowed with therapeutic benefits especially in skincare due to its unique curative properties. The present study focused on an environmental friendly and rapid method of phytosynthesis of silver nanoparticles (Ag-NPs) using A. vera gel extract as a reductant. The synthesized Ag-NPs were characterized by transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared (FTIR), and dynamic light scattering (DLS). TEM micrographs showed spherical-shaped synthesized Ag-NPs with a diameter of 50–100 nm. The UV-Vis spectrum displayed a broad absorption peak of surface plasmon resonance (SPR) at 450 nm. The mean size and size distribution of the formed Ag-NPs were investigated using the DLS technique. Antibacterial studies revealed zones of inhibition by Ag-NPs of A. vera (9 and 7 mm) against Pseudomonas aeruginosa and Escherichia coli, respectively. Furthermore, the antifungal activity was screened, based on the diameter of the growth inhibition zone using the synthesized Ag-NPs for different fungal strains. Anticancer activity of the synthesized Ag-NPs against the mouse melanoma F10B16 cell line revealed 100% inhibition with Ag-NPs at a concentration of 100 µg mL−1. The phytosynthesized Ag-NPs demonstrated a marked antimicrobial activity and also exhibited a potent cytotoxic effect against mouse melanoma F10B16 cells. The key findings of this study indicate that synthesized Ag-NPs exhibit profound therapeutic activity and could be potentially ideal alternatives in medicinal applications.

scholarly journals Reducing the Crystallite Size of Spherulites in PEO-Based Polymer Nanocomposites Mediated by Carbon Nanodots and Ag Nanoparticles

Nanomaterials ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 874 ◽  
Author(s):  
Ranjdar Abdullah ◽  
Shujahadeen Aziz ◽  
Soran Mamand ◽  
Aso Hassan ◽  
Sarkawt Hussein ◽  
...  
Keyword(s):  
Crystallite Size ◽  
Polymer Nanocomposites ◽  
Electron Transition ◽  
Peak Position ◽  
Carbon Nanodots ◽  
Ag Nps ◽  
Peak Broadening ◽  
Vis Spectroscopy ◽  
Solution Cast ◽  
Significant Change

The PEO-based polymer nanocomposites were prepared by solution cast method. Green approaches were used for synthesis of carbon nanodots (CNDs) and silver nanoparticles (Ag NPs). It was found that the crystallite size of spherulites of PEO was greatly scarified upon incorporation of CNDs and Ag NPs. In the present work, in opposition to other studies, broadening of surface plasmon resonance (SPR) peak of metallic Ag NPs in PEO-based polymer composites was observed rather than peak tuning. Various techniques, such as powder X-ray diffraction (XRD), SEM, UV–Vis spectroscopy, and photoluminescence (PL), were used to characterize the structural, morphological, and optical properties of the samples. Increase of amorphous phase for the PEO doped with CND particles was shown from the results of XRD analyses. Upon the addition of suspended Ag NPs to the PEO:CNDs composites, significant change of XRD peak position was seen. A field-emission scanning electron microscope (FESEM) was used to investigate the surface morphology of the samples. In the SEM, a significant change in the crystalline structure was seen. The size of PEO spherulites in the PEO nanocomposite samples became smaller and the percentage of amorphous portion became larger, owing to the distribution of CNDs and Ag NPs. The UV–Vis absorption spectra of the PEO-based polymer were found to improve and shift to higher wavelengths upon incorporation of CNDs and Ag NPs into the PEO matrix. The SPR peak broadening in the UV–Vis spectra was observed in the PEO:CNDs composites due to the Ag NPs. The absorption edge value of PEO was found to shift toward lower photon energy as the CNDs and Ag NPs are introduced. The photoluminescence (PL) spectra were also observed for the PEO:CNDs and PEO:CNDs:Ag samples and found to be more intense in the PEO:CNDs system than in the PEO:CNDs:Ag system. Lastly, the optical band gap of the samples was further studied in detail using of Tauc’s model and optical dielectric loss parameter. The types of electron transition were specified.

scholarly journals Optimization of Green Synthesis of Silver Nanoparticles from Leaf Extracts ofPimenta dioica(Allspice)

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Akshay Rajeev Geetha ◽  
Elizabeth George ◽  
Akshay Srinivasan ◽  
Jameel Shaik
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Leaf Extract ◽  
Synthesis Method ◽  
Leaf Extracts ◽  
Synthesis Of Nanoparticles ◽  
Hot Air ◽  
Vis Spectroscopy ◽  
Pimenta Dioica ◽  
First Time

Production of silver nanoparticles from the leaf extracts ofPimenta dioicais reported for the first time in this paper. Three different sets of leaves were utilized for the synthesis of nanoparticles—fresh, hot-air oven dried, and sun-dried. These nanoparticles were characterized using UV-Vis spectroscopy and AFM. The results were diverse in that different sizes were seen for different leaf conditions. Nanoparticles synthesized using sun-dried leaves (produced using a particular ratio (1 : 0.5) of the leaf extract sample and silver nitrate (1 mM), resp.) possessed the smallest sizes. We believe that further optimization of the current green-synthesis method would help in the production of monodispersed silver nanoparticles having great potential in treating several diseases.

scholarly journals Extrusion Processing of Amaranth and Quinoa into Gluten-Free Snack Foods for Celiac and Gluten-Free Diets

2017 ◽  
Vol 6 (5) ◽  
pp. 107
Author(s):  
Caitlin Gearhart ◽  
Kurt A. Rosentrater
Keyword(s):  
Scale Up ◽  
Food Products ◽  
Poor Quality ◽  
Expansion Ratio ◽  
Gluten Free ◽  
Experimental Conditions ◽  
Snack Foods ◽  
Extrusion Processing ◽  
Nutritional Benefits ◽  
First Time

Because of the growth of gluten intolerance and Celiac disease, there is growing interest in development of gluten-free foods. Beyond just being gluten-free, such foods can also have other positive nutritional benefits to human health. Extrusion processing is commonly used to produce a wide variety of human food products. Gluten-free grains can be a processing challenge, however, due to lack of proper binding, which can lead to poor quality food products. This research explores how extrusion parameters impacted the quality of amaranth- and quinoa-based extrudates. The specific objectives of this project included extruding each of the grains, then measuring extrudate properties, such as color, unit density, expansion ratio, and durability. Both the quinoa and amaranth were extruded as raw grain, as well as ground to 2mm and 1mm particle sizes. Other experimental conditions included moisture contents of 20% and 40% (d.b.), and extruder screw speeds of 50 rpm and 100 rpm. All treatments were successfully extruded, and all extrudates had high quality attributes, making this the first time either quinoa or amaranth was extruded without any binding ingredients. This study provides information useful for commercial scale-up.

scholarly journals The Susceptibility of Meningococci to the Antimicrobial Agents in Moscow 2006 - 2015

2016 ◽  
Vol 15 (3) ◽  
pp. 7-14 ◽  
Author(s):  
M. A. Koroleva ◽  
I. S. Koroleva ◽  
I. M. Zakroeva ◽  
I. M. Gruber
Keyword(s):  
Cerebrospinal Fluid ◽  
Continuous Monitoring ◽  
Antimicrobial Agents ◽  
Meningococcal Infection ◽  
Test Results ◽  
Prognostic Criteria ◽  
Comparison Results ◽  
Moderately Resistant ◽  
First Time

Relevance. One of the prognostic criteria meningococcal infection (MI) epidemic status process is the increasing number of resistant to antibiotics meningococcal strains. Aim of this study was to investigate the dynamics of invasive strains of N. meningitidis susceptibility to antibiotics in Moscow in 2006 - 2015. Materials and methods. Studied 98 strains of N. meningitidis, isolated from blood and cerebrospinal fluid of patients with MI. The study changes of sensitivity N. meningitidis to antibiotics was occured in two periods: first -2006 - 2011 and second - 2012 - 2015. The MIC was determined by E-test. Results. In the present study revealed for the first time the Russian strains of N. meningitidis, moderately resistant to penicillin (5 strains) and resistant to rifampicin (3 strains). Among the studied strains were not found resistant to ceftriaxone, ciprofloxacin, tetracycline and chloramphenicol. Discussion. Comparison results two study periods allowed to reveal the dynamics of increasing the sensitivity of N. meningitidis to antibiotics, which confirms the decline in meningococcal virulence, and as a result, continued interepidemic MI period. Conclusions. Despite the decline antibakterial resistance is required continuous monitoring.

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