Green Synthesis of Silver Nanoparticles: Structural Features andIn VivoandIn VitroTherapeutic Effects againstHelicobacter pyloriInduced Gastritis

This study evaluatesin vivoandin vitroanti-Helicobacter pylori (H. pylori)efficacy of silver nanoparticles (Ag-NPs) prepared via a cost-effective green chemistry route whereinPeganum harmalaL. seeds extract was used as a reducing and capping agent. The structural features, as elucidated by surface plasmon resonance spectrophotometry, transmission electron microscopy, and powder X-ray diffraction spectroscopy, revealed the Ag-NPs synthesized to be polydispersed in nature and spherical in shape with 5–40 nm size. A typical Ag-NPs suspension (S5), with size being 15 nm, when testedin vitroagainst forty-two local isolates and two reference strains, showed a considerable anti-H. pyloriactivity. In case ofin vivotrial againstH. pyloriinduced gastritis, after oral administration of 16 mg/kg body weight of S5for seven days, a complete clearance was recorded in male albino rates. In comparative time-killing kinetics, S5exhibited dose- and time-dependent anti-H. pyloriactivity that was almost similar to tetracycline and clarithromycin, less than amoxicillin, but higher than metronidazole. Furthermore, S5was found to be an equally effective anti-H. pyloriagent at low (≤4) and high pH with no drug resistance observed even up to 10 repeated exposures while a significant drug resistance was recorded for most of the standard drugs employed. The present results revealed the potential of the synthesized Ag-NPs as safer bactericidal agents for the treatment ofH. pyloriinduced gastritis.

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Polyamines and Related Nitrogen Compounds in the Chemotherapy of Neglected Diseases Caused by Kinetoplastids

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666180427151338 ◽

2018 ◽

Vol 18 (5) ◽

pp. 321-368 ◽

Cited By ~ 2

Author(s):

Juan A. Bisceglia ◽

Maria C. Mollo ◽

Nadia Gruber ◽

Liliana R. Orelli

Keyword(s):

Drug Targets ◽

Redox Homeostasis ◽

Cost Effective ◽

Structural Features ◽

Mammalian Host ◽

Neglected Diseases ◽

Nitrogen Compounds ◽

Chemical Structures

Neglected diseases due to the parasitic protozoa Leishmania and Trypanosoma (kinetoplastids) affect millions of people worldwide, and the lack of suitable treatments has promoted an ongoing drug discovery effort to identify novel nontoxic and cost-effective chemotherapies. Polyamines are ubiquitous small organic molecules that play key roles in kinetoplastid parasites metabolism, redox homeostasis and in the normal progression of cell cycles, which differ from those found in the mammalian host. These features make polyamines attractive in terms of antiparasitic drug development. The present work provides a comprehensive insight on the use of polyamine derivatives and related nitrogen compounds in the chemotherapy of kinetoplastid diseases. The amount of literature on this subject is considerable, and a classification considering drug targets and chemical structures were made. Polyamines, aminoalcohols and basic heterocycles designed to target the relevant parasitic enzyme trypanothione reductase are discussed in the first section, followed by compounds directed to less common targets, like parasite SOD and the aminopurine P2 transporter. Finally, the third section comprises nitrogen compounds structurally derived from antimalaric agents. References on the chemical synthesis of the selected compounds are reported together with their in vivo and/or in vitro IC50 values, and structureactivity relationships within each group are analyzed. Some favourable structural features were identified from the SAR analyses comprising protonable sites, hydrophobic groups and optimum distances between them. The importance of certain pharmacophoric groups or amino acid residues in the bioactivity of polyamine derived compounds is also discussed.

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Size Control of Synthesized Silver Nanoparticles by Simultaneous Chemical Reduction and Laser Fragmentation in Origanum majorana Extract: Antibacterial Application

Materials ◽

10.3390/ma14092326 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2326

Author(s):

Entesar Ali Ganash ◽

Reem Mohammad Altuwirqi

Keyword(s):

Silver Nanoparticles ◽

Irradiation Time ◽

Chemical Reduction ◽

Size Control ◽

Reduction Process ◽

Laser Wavelength ◽

X Ray Diffraction ◽

Ag Nps ◽

Transmission Electron ◽

Origanum Majorana

In this work, silver nanoparticles (Ag NPs) were synthesized using a chemical reduction approach and a pulsed laser fragmentation in liquid (PLFL) technique, simultaneously. A laser wavelength of 532 nm was focused on the as produced Ag NPs, suspended in an Origanum majorana extract solution, with the aim of controlling their size. The effect of liquid medium concentration and irradiation time on the properties of the fabricated NPs was studied. While the X-ray diffraction (XRD) pattern confirmed the existence of Ag NPs, the UV–Vis spectrophotometry showed a significant absorption peak at about 420 nm, which is attributed to the characteristic surface plasmon resonance (SPR) peak of the obtained Ag NPs. By increasing the irradiation time and the Origanum majora extract concentration, the SPR peak shifted toward a shorter wavelength. This shift indicates a reduction in the NPs’ size. The effect of PLFL on size reduction was clearly revealed from the transmission electron microscopy images. The PLFL technique, depending on experimental parameters, reduced the size of the obtained Ag NPs to less than 10 nm. The mean zeta potential of the fabricated Ag NPs was found to be greater than −30 mV, signifying their stability. The Ag NPs were also found to effectively inhibit bacterial activity. The PLFL technique has proved to be a powerful method for controlling the size of NPs when it is simultaneously associated with a chemical reduction process.

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Silver nanoparticles used to counter Monilinia fructicola fungicide-resistance and reduce fungicide environmental footprint

10.5194/egusphere-egu21-9285 ◽

2021 ◽

Author(s):

Constantinos Chrysikopoulos ◽

Anastasios A. Malandrakis ◽

Nektarios Kavroulakis ◽

Anthi Stefanarou

Keyword(s):

Silver Nanoparticles ◽

Control Plant ◽

Resistance Mutation ◽

Silver Ions ◽

Apple Fruit ◽

Ag Nps ◽

Gene Target ◽

Benzimidazole Fungicides

<div>The potential of silver nanoparticles (Ag-NPs) to control plant pathogen Moniliafructicola and to deter environmental contamination by reducing fungicide doses was evaluated in vitro and in vivo. &#160;Fungitoxicity screening of&#160;M. fructicola&#160;isolates resulted in the detection of 18 benzimidazole-resistant (BEN-R) isolates with reduced sensitivity to fungicides &#160;thiophanate methyl (TM)&#160; and carbendazim. All resistant isolates caried the E198A resistance mutation in their &#946;-tubulin gene, target site of the benzimidazole fungicides.&#160;Ag-NPs could effectively control both sensitive (BEN-S) and resistant isolates while the combination of Ag-NPs with TM significantly enhanced their fungitoxic effect both in vitro&#160;and in apple fruit tests. The positive correlation observed between Ag-NPs and TM+Ag-NPs treatments indicates a mixture-enhanced Ag-NPs activity/availability as a possible mechanism of synergy. No correlation between Ag-NPs&#160; and AgNO3&#160;could&#160; be found suggesting difference(s) in the fungitoxic mechanism of action between Nps and their bulk/ionic counterparts. Indications of the involvement of energy (ATP) metabolism in the mode of action of Ag-NPs were also evident by the synergy observed between Ag-NPs and the oxidative phosphorylation-uncoupler fluazinam (FM) against both BEN-R and BEN-S phenotypes. The role of silver ions release on the inhibitory action of Ag-NPs against the fungusis probably limited since the AgNPs/NaCl combination enhanced fungitoxicity, a fact that could not be justified by the expected binding of silver with chlorine ions. Concluding, Ag-NPs can be effectively used as a means of controlling both BEN-S and BEN-R M.&#160;fructicola&#160;isolates while&#160;their combination with conventional fungicides should aid anti-resistant strategies and reduce the environmental impact of synthetic fungicides by reducing effective doses to the control the pathogen.</div>

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Synthesis and Characterization of Bone Cement (Hydroxyapatite Base) Calcinated at 900°C and Loading the Silver Nanoparticles on it

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.893 ◽

2012 ◽

Vol 622-623 ◽

pp. 893-896

Author(s):

H.R. Ebrahimi ◽

M. Eslami

Keyword(s):

Silver Nanoparticles ◽

Bone Cancer ◽

Calcium Hydroxyapatite ◽

Chemical Precipitation ◽

X Ray Diffraction ◽

Ag Nps ◽

X Ray ◽

Agno3 Solution ◽

Transmission Electron

The bioceramics, calcium hydroxyapatite (HA), is a material which is biocompatible to the human body and is well suited to be used in hyperthermia applications for the treatment of bone cancer. We synthesis hydroxyapatite in modified synthetic body fluid (SBF) solutions at 37°C and pH of 7.4 using a novel chemical precipitation technique. Then after heat operation, on filtered precipitated result HA were produced. For loading the silver nanoparticles (Ag NPs) on the hydroxyapatite we use AgNO3 solution. And for reducing Ag+ ions apply sodium borohydrate solution. The formations of the silver nanoparticles on the HAP structure were confirmed by X-ray diffraction, transmission electron microscopy (TEM). TEM image show the nanostructure of silver particles, being formed on hydroxyapatite texture.

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Alginate-Mediated Synthesis of Hetero-Shaped Silver Nanoparticles and Their Hydrogen Peroxide Sensing Ability

Molecules ◽

10.3390/molecules25030435 ◽

2020 ◽

Vol 25 (3) ◽

pp. 435 ◽

Cited By ~ 3

Author(s):

Sneha Bhagyaraj ◽

Igor Krupa

Keyword(s):

Hydrogen Peroxide ◽

Particle Size ◽

Silver Nanoparticles ◽

Linear Response ◽

X Ray Diffraction ◽

Ag Nps ◽

X Ray ◽

Transmission Electron ◽

Wide Range ◽

Pollution Detection

A new method for the simple synthesis of stable heterostructured biopolymer (sodium alginate)-capped silver nanoparticles (Ag-NPs) based on green chemistry is reported. The as-prepared nanoparticles were characterized using the ultraviolet-visible (UV-Vis) absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS) techniques. The results showed that the as-prepared Ag-NPs have a heterostructured morphology with particle size in the range 30 ± 18–60 ± 25 nm, showing a zeta potential of −62 mV. The silver nanoparticle formation was confirmed from UV-Vis spectra showing 424 nm as maximum absorption. The particle size and crystallinity of the as-synthesized nanoparticles were analyzed using TEM and XRD measurements, respectively. FTIR spectra confirmed the presence of alginate as capping agent to stabilize the nanoparticles. The Ag-NPs also showed excellent sensing capability, with a linear response to hydrogen peroxide spanning a wide range of concentrations from 10−1 to 10−7 M, which indicates their high potential for water treatment applications, such as pollution detection and nanofiltration composites.

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Evaluation of genotoxic effect of silver nanoparticles (Ag-Nps) in vitro and in vivo

Journal of Nanoparticle Research ◽

10.1007/s11051-012-0791-y ◽

2012 ◽

Vol 14 (4) ◽

Cited By ~ 18

Author(s):

Priscila Tavares ◽

Fernanda Balbinot ◽

Hugo Martins de Oliveira ◽

Gabriela Elibio Fagundes ◽

Mireli Venâncio ◽

...

Keyword(s):

Silver Nanoparticles ◽

Genotoxic Effect ◽

Ag Nps

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In Vivo Effect of Different Doses of Silver Nanoparticles on the Seminiferous Tubules in Albino Rats: Histopathological Study

Engineering and Technology Journal ◽

10.30684/etj.v38i1b.1694 ◽

2020 ◽

Vol 38 (1B) ◽

pp. 1-5

Author(s):

Ruqayah A. Salman ◽

Abdulrahman K. Ali ◽

Amenah Ali Salman

Keyword(s):

Silver Nanoparticles ◽

Harmful Effect ◽

Seminiferous Tubules ◽

Albino Rats ◽

Histopathological Study ◽

Ag Nps ◽

Average Size ◽

Different Doses

The study aims to investigate the effects of silver nanoparticles (Ag NPs) on the seminiferous tubules in Albino rats. Several in vitro studies have been performed in different cell models, using various nanoparticles. Pure and spherical AgNPs with an average size of 30 nm, was injected into two groups of male albino rats (6 rats for each group) in different doses. Histopathological changes in testis tissues were showed a harmful effect of the silver nanoparticles, manifested by reducing the number of spermatogenic cells, and a decrease in the number of leyidg´s cells (group 1), and hypotrophy in seminiferous and enlargement in interstitial spaces in group 2.

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Fungus-mediated green synthesis of nano-silver using Aspergillus sydowii and its antifungal/antiproliferative activities

Scientific Reports ◽

10.1038/s41598-021-89854-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dongyang Wang ◽

Baiji Xue ◽

Lin Wang ◽

Yidi Zhang ◽

Lijun Liu ◽

...

Keyword(s):

Color Change ◽

Cost Effective ◽

Pathogenic Fungi ◽

Aspergillus Sydowii ◽

X Ray Diffraction ◽

Synthesis Conditions ◽

Transmission Electron ◽

Increasing Demand ◽

Culture Supernatants

AbstractDue to the increasing demand for eco-friendly, cost-effective and safe technologies, biosynthetic metal nanoparticles have attracted worldwide attention. In this study, silver nanoparticles (AgNPs) were extracellularly biosynthesized using the culture supernatants of Aspergillus sydowii. During synthesis, color change was preliminarily judge of the generation of AgNPs, and the UV absorption peak at 420 nm further confirms the production of AgNPs. Transmission electron microscopy and X-ray diffraction were also used to identify the AgNPs. The results shows that AgNPs has crystalline cubic feature and is a polydisperse spherical particle with size between 1 and 24 nm. Three main synthesis factors (temperature, pH and substrate concentration) were optimized, the best synthesis conditions were as follows 50 °C, 8.0 and 1.5 mM. In the biological application of AgNPs, it shows effective antifungal activity against many clinical pathogenic fungi and antiproliferative activity to HeLa cells and MCF-7 cells in vitro. Our research finds a new path to biosynthesis of AgNPs in an eco-friendly manner, and bring opportunity for biomedical applications in clinic.

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Silver Nanoparticles in Alveolar Bone Surgery Devices

Journal of Nanomaterials ◽

10.1155/2012/975842 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 28

Author(s):

Stefano Sivolella ◽

Edoardo Stellini ◽

Giulia Brunello ◽

Chiara Gardin ◽

Letizia Ferroni ◽

...

Keyword(s):

Silver Nanoparticles ◽

Dental Implant ◽

Animal Studies ◽

Alveolar Bone ◽

Antimicrobial Properties ◽

Ag Nps ◽

Augmentation Techniques ◽

Dental Implant Surgery

Silver (Ag) ions have well-known antimicrobial properties and have been applied as nanostrategies in many medical and surgical fields, including dentistry. The use of silver nanoparticles (Ag NPs) may be an option for reducing bacterial adhesion to dental implant surfaces and preventing biofilm formation, containing the risk of peri-implant infections. Modifying the structure or surface of bone grafts and membranes with Ag NPs may also prevent the risk of contamination and infection that are common when alveolar bone augmentation techniques are used. On the other hand, Ag NPs have revealed some toxic effects on cellsin vitroandin vivoin animal studies. In this setting, the aim of the present paper is to summarize the principle behind Ag NP-based devices and their clinical applications in alveolar bone and dental implant surgery.

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Green production of silver nanoparticles, evaluation of their nematicidal activity against Meloidogyne javanica and their impact on growth of faba bean

Beni-Suef University Journal of Basic and Applied Sciences ◽

10.1186/s43088-019-0010-3 ◽

2019 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Seham M. Hamed ◽

Eman S. Hagag ◽

Neveen Abd El-Raouf

Keyword(s):

Silver Nanoparticles ◽

Plant Growth ◽

Faba Bean ◽

Meloidogyne Javanica ◽

Plant Diseases ◽

Ag Nps ◽

Vitro Assay ◽

Vis Spectroscopy

Abstract Background Cyanobacterium-based silver nanoparticles are considered not only as an efficient nano-nematicide but also as a bio-stimulant material for plant growth. They could be employed as a part of an integrated program for controlling some plant diseases. Results In this study, silver nanoparticles (Ag-NPs) were biosynthesized from aqueous extract of the cyanobacterium, Nostoc sp. PCC7524. Full characterization of the biosynthesized Ag-NPs was monitored by UV-vis spectroscopy, transmission electron microscopy, X-ray diffraction pattern, Zeta sizer, and Fourier transform infrared spectroscopy. In vitro assay against the root-knot nematode Meloidogyne javanica showed that Ag-NPs significantly decreased egg hatching of M. javanica at different applied concentrations (3, 6, 12, 25, and 50%, v/v). Fifty percent of Ag-NPs induced the highest reduction percent (94.66%). Moreover, Ag-NPs and AgNO3 significantly increased the percentages of larval mortality of the second-stage juveniles (J2) with concentration and time-dependent responses. Ag-NPs or AgNO3 at 2.4 ml/l, 24 h, completely inhibited the growth of J2 compared to 23% inhibition using aqueous cyanobacterial extract (ACE). In vivo effect of Ag-NPs on faba bean-infected plant under greenhouse conditions was achieved by treating soil with three different concentrations of 1, 2, and 3 ml/kg soil over two consecutive seasons. Ag-NPs significantly reduced root galling from 39.6 to 78.7% and J2 population in the soils from 32.2% to 86.7% in the 2018 season and from 21.9 to 78.1% and 40.0 to 81.0% in the 2019 season, respectively. Moreover, 3 ml/kg soil of Ag-NP treatment showed statistically comparable effects to that of vydate nematicide but with remarkable enhancement of faba bean growth parameters as compared to those of vydate or AgNO3 treatments in the two seasons. Conclusions The considerable in vitro and in vivo nematicidal potential of the cyanobacterium-based Ag-NPs, besides their bio-stimulant effect on plant growth, makes them feasible for the biological control of M. javanica.

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