Phytogenic Synthesis of Nano Silver from Madagascar Periwinkle Extracts and Their Angiogenic Activities in Zebrafish Embryos (ZFE)

2020 ◽  
Vol 12 (1) ◽  
pp. 79-87
Author(s):  
Govindarajan Kathiravan ◽  
Kosuru Rekha Yamini ◽  
Kalyanaraman Rajagopal ◽  
Sambandam Anandan ◽  
Kwang Jin Kim ◽  
...  

Green biosynthesis of silver nanoparticles utilizing plant extracts is a simple, cost effective system of generating nanoparticles in an ecofriendly environment. In the present study, biosynthesis of silver nanoparticles was carried out using different parts of Madagascar periwinkle plant extracts. The production of the silver nanoparticles (AgNPs) was detected visually by change in color of the reaction mixture from yellow to reddish brown in a 8 h treatment at 37 °C. Further, the AgNPs were analyzed by various standard characterization techniques such UV-Vis spectroscopy, Electron Microscopy (TEM and SEM), FT-IR, and GC-MS analysis. The UV-Visible spectrum showed the plasmon resonance peak for AgNPs at 435 nm, indicating the formation of silver nanoparticles. FTIR analysis showed a good interaction between the plant extract and NPs. The morphology of the NPs varied in shape has observed through TEM with the particle size less than 10 nm. The phytoformulated nanoparticles were found to be well dispersed in solution and stable due to capping molecules present in the reaction mixture. The chromatographic analysis (GC-MS) displayed a prominent fragmentation pattern especially at the higher molecular weight in the range of 280 to 271. Angiogenesis is an important physiological process that plays a crucial role in several pathological conditions (tumor growth and metastasis). The green synthesized AgNPs were assessed for their angiogenic inhibition properties using zebrafish embryos as a model system. The biogenic AgNPs treatment at the dose of 100 μl and 150 μl showed significant anti-angiogenesis (inhibitory effect on angiogenesis), which represents more effectiveness in controlling the vessel formation during pathological conditions.

2012 ◽  
Vol 585 ◽  
pp. 134-138 ◽  
Author(s):  
Alisha Goyal ◽  
Jyoti Rozra ◽  
Isha Saini ◽  
Pawan K. Sharma ◽  
Annu Sharma

Nanocomposite films of Poly (methylmethacrylate) with different concentration of silver nanoparticles were prepared by ex-situ method. Firstly, silver nanoparticles were obtained by reducing the aqueous solution of silver nitrate with sodium borohydride then Ag-PMMA films were prepared by mixing colloidal solution of silver nanoparticles with solution of polymer. Thin solid films were structurally characterized using UV-VIS spectroscopy and TEM. The appearance of surface plasmon resonance peak, characteristic of silver nanoparticles at 420 nm in UV-VIS absorption spectra of Ag-PMMA films confirms the formation of Ag-PMMA nanocomposite. TEM showed Ag nanoparticles of average size 8 nm embedded in PMMA matrix. Analysis of absorption and reflection data indicates towards the reduction in optical band gap and increase in refractive index of the resulting nanocomposite. The synthesized Ag-PMMA nanocomposite has been found to be more conducting than PMMA as ascertained using I-V studies. The decrease in band gap and increase in conductivity can be correlated due to the formation of localized electronic states in PMMA matrix due to insertion of Ag nanoparticles. The PMMA thin films with dispersed silver nanoparticles may be useful for nanophotonic devices.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Preetha Devaraj ◽  
Prachi Kumari ◽  
Chirom Aarti ◽  
Arun Renganathan

Cannonball (Couroupita guianensis) is a tree belonging to the family Lecythidaceae. Various parts of the tree have been reported to contain oils, keto steroids, glycosides, couroupitine, indirubin, isatin, and phenolic substances. We report here the synthesis of silver nanoparticles (AgNPs) using cannonball leaves. Green synthesized nanoparticles have been characterized by UV-Vis spectroscopy, SEM, TEM, and FTIR. Cannonball leaf broth as a reducing agent converts silver ions to AgNPs in a rapid and ecofriendly manner. The UV-Vis spectra gave surface plasmon resonance peak at 434 nm. TEM image shows well-dispersed silver nanoparticles with an average particle size of 28.4 nm. FTIR showed the structure and respective bands of the synthesized nanoparticles and the stretch of bonds. Green synthesized silver nanoparticles by cannonball leaf extract show cytotoxicity to human breast cancer cell line (MCF-7). Overall, this environmentally friendly method of biological silver nanoparticles production provides rates of synthesis faster than or comparable to those of chemical methods and can potentially be used in various human contacting areas such as cosmetics, foods, and medical applications.


Author(s):  
Lidia Meléndez-Balbuena ◽  
Eric Reyes-Cervantes ◽  
Blanca Martha Cabrera-Vivas ◽  
Maribel Arroyo

The objective of this work was to synthesize the synthesis of silver nanoparticles using as a reducing agent of ionic silver the plant extract of Dandelion (Taraxacun officianale), vegetable of high availability and low cost, as an alternative to the processes conventional, based on the antioxidant capacity of plant extracts that reduce metals in solution. The nanoparticles prepared by this method were characterized by the golden yellow color characteristic of silver nanoparticle solutions. Measurements with UV-Vis spectroscopy of aqueous solutions of Ag1 + ions after coming into contact with plant extracts of Dandelion at different pHs showed an intense absorption band around 400-450 nm, characteristic of the resonance of the Plasmon of silver nanoparticles. Through the scanning of the samples by means of AFM (atomic force microscopy), morphological information of the nanoparticles is obtained, from 3D topographic images of them, such as distribution, size and shape of the silver nanoparticles. Finally, its antibacterial activity was tested against the Escherichia coli strain.


Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1005
Author(s):  
Aneta Salayová ◽  
Zdenka Bedlovičová ◽  
Nina Daneu ◽  
Matej Baláž ◽  
Zdenka Lukáčová Bujňáková ◽  
...  

A green synthetic route for the production of silver nanoparticles (AgNPs) using five different aqueous plant extracts, namely, Berberis vulgaris, Brassica nigra, Capsella bursa-pastoris, Lavandula angustifolia and Origanum vulgare, was investigated in this study. The present work demonstrates the influence of plant extract composition (antioxidant and total phenolic content) on the size and morphology of the produced AgNPs. The biosynthetic procedure was rapid and simple and was easily monitored via colour changes and ultraviolet and visible (UV-Vis) spectroscopy. Subsequently, measurement of zeta potential (ZP), photon cross-correlation spectroscopy (PCCS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analysis were employed to characterise the as-synthesised nanoparticles. The XRD investigation confirmed the presence of Ag0 in the nanoparticles, and interactions between the bioactive compounds of the plants and the produced AgNPs were evident in the FTIR spectra. TEM indicated that the nanoparticles exhibited a bimodal size distribution, with the smaller particles being spherical and the larger having a truncated octahedron shape. In addition, the antimicrobial activity of the AgNPs was tested against five bacterial strains. All synthesised nanoparticles exhibited enhanced antimicrobial activity at a precursor concentration of 5 mM compared to the control substance, gentamicin sulphate, with the best results observed for AgNPs prepared with B. nigra and L. angustifolia extracts.


2017 ◽  
Vol 19 (4) ◽  
pp. 128-136 ◽  
Author(s):  
Saviour A. Umoren ◽  
Alexis M. Nzila ◽  
Saravanan Sankaran ◽  
Moses M. Solomon ◽  
Peace S. Umoren

Abstract Silver nanoparticles (AgNPs) have been synthesized in the presence of Strawberry fruit extract (SBFE) at room temperature. The synthesized AgNPs was characterized by UV-vis spectroscopy, SEM, EDS, XRD, TEM and FTIR. The UV-vis spectra of the AgNPs show SPR band at 450 nm. TEM results indicate that AgNPs are spherical in shape and size range between 7–65 nm. Antibacterial activity of the synthesized AgNPs has been assessed against Pseudomonas aeruginosa and Bacillus licheniformis. The results show that AgNPs exhibit inhibitory effect and effect is a function of AgNPs concentration. The antibacterial activity of the prepared AgNPs has been compared with two antibiotics, amoxicillin and ciprofloxacin. It is found that the antibiotics perform better than AgNPs.


2019 ◽  
Vol 10 (4) ◽  
pp. 3636-3643
Author(s):  
Hor Jia Wei ◽  
Mohd. Syafiq Awang ◽  
Nor Dyana ◽  
Daruliza Kernain ◽  
Yazmin Bustami

Silver nanoparticles (AgNPs) has long known for its inhibitory and bactericidal effects. However, due to its’ attractive antibacterial property, on-going research with various synthesis strategies actively been conducted. In this study, the synthesis of AgNPs was reported, using a simple chemical reduction method with citrate as the reducing agent TEM was used to characterize the obtained AgNPs. Then, Staphylococcus aureus and Escherichia coli were used to identify the antibacterial activity of AgNPs. The inhibition effects of AgNPs against these two bacteria were observed via disc diffusion, and MIC assays and the effects of AgNPs mode of action on both bacteria were further observed under TEM. The formation of AgNPs at ̴ 400 nm, which is the surface plasmon resonance peak was observed using Uv-Vis spectroscopy. The size of AgNPs mostly in the range of 1-10 nm and their morphology appeared to be spherical. Based on the MIC assay, Escherichia coli exhibit low MIC value with 0.049 mg/ml as compared to Staphylococcus aureus with0.391 mg/ml MIC value; correspond to the effective antibacterial activity by the citrate-reduced AgNPs. Further observation on the bacterial surface structure can be seen with cross-sectional TEM image, and it provides an insight into the AgNPs mechanistic aspects of AgNPs against Staphylococcus aureus and Escherichia coli. Silver nanoparticles have been successfully synthesised using the citrate reduction method. Results obtained in this study thus elucidating promising findings to employed AgNPs as an antibacterial agent, and this composition needs to be further study and develop into an antibacterial agent.


2020 ◽  
Vol 14 (3) ◽  
pp. 250-258
Author(s):  
Jose E. Quiroz-Hernández ◽  
Oxana V. Kharissova ◽  
Victor E. Aguirre-Arzola ◽  
Guillermo C.G. Martinez-Avila ◽  
Uziel Castillo-Velazquez

Aims: To use an agroindustrial waste (orange peels) as a source of polyphenols as a reducing medium for obtaining silver nanoparticles by greener method. Background: Several techniques have been employed for AgNPs synthesis, nevertheless, most of them involve the use of toxic chemicals in the process. The use of fungi, bacteria, and plant extracts as subtracts for green synthesis is an ecofriendly alternative, although hypothetic, route for AgNPs large scale synthesis. In the case of plant extracts, it is believed that polyphenols are the biomolecules responsible for the reduction and stabilization of the Ag+ ions into AgNPs, being a sustainable and ecological option; polyphenols could be obtained from plant waste and agroindustrial subproducts. Objective: To develop an efficient, greener, and low-cost method of AgNPs production using natural products. Methods: The basic principle of silver nanoparticles synthesis is the interaction in a mixture of silver nitrate (source of Ag+ ions) and the orange peel extract (reducing and stabilizing agent) under certain conditions. Five treatments were carried out, evaluating several parameters during AgNPs synthesis such as pH, orange peel extract-silver nitrate ratio, time and conditions of incubation, irradiation of UV light, irradiation of microwave, and temperature. Result: The synthesis of silver nanoparticles from an agroindustrial waste as the orange peel was successfully carried out and checked by visual evaluation, UV-Vis spectroscopy, and EDS analysis. The particle size was estimated between 42.82 nm to 151.75 nm, having a spherical and ovoid morphology. Discussion: Through the analysis of several synthesis conditions, it has become possible to establish a suitable treatment to increase antibacterial yield and evaluate morphology and size traits in order to acquire the best conditions for a future industrial scale synthesis. Conclusion: The orange peel aqueous extract resulted as a great source of polyphenols, allowing the successful synthesis of silver nanoparticles in mild conditions. Thus, obtained AgNPs revealed an increased antibacterial effect and potential against Gram-positive bacteria such as Staphyloccocus aureus.


2019 ◽  
Vol 70 (11) ◽  
pp. 4053-4056

This paper presents a simple and eco-friendly method for the synthesis of silver nanoparticles (AgNPs) using licorice (Glycyrrhiza glabra) root extract and the evaluation of their antioxidant activity. UV-Vis spectroscopy, FTIR, TEM and EDX methods were used to characterize the AgNPs. The UV-Vis spectrum shows the characteristic surface plasmon resonance peak at 430 nm. The synthesized AgNPs have a spherical shape and are capped by biomolecules. Furthermore, FTIR spectra and EDX analysis demonstrate the presence of phytochemicals from extract which act as reducing and stabilizing agents. The presence of elemental silver was demonstrated by the peak at 3 keV from EDX spectra. The results following the DPPH free radical scavenging assay suggest that AgNPs present a better antioxidant activity compared to that of the extract. Therefore, the obtained results confirm that licorice represents a source of biomolecules that can be used for synthesizing AgNPs with antioxidant potential. Keywords: licorice, green synthesis, silver nanoparticles, antioxidant activity


2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
M. A. Pedroza-Toscano ◽  
S. López-Cuenca ◽  
M. Rabelero-Velasco ◽  
E. D. Moreno-Medrano ◽  
A. P. Mendizabal-Ruiz ◽  
...  

Preparation of silver nanoparticles was carried out by semicontinuous reduction of Ag+ ions at low temperatures. Silver nitrate was used as the Ag0 precursor, the carboxymethyl cellulose (CMC) as stabilizer and primary reducing agent, and sodium borohydride as reducing agent. Weight ratios of 1 : 1 and 1 : 2 of AgNO3 : CMC were used for carrying out the reactions. Silver nanoparticles were characterized by UV-VIS spectroscopy, transmission electronic microscopy (TEM), and X-ray diffraction (XRD). The formation of silver nanoparticles was confirmed by XRD spectroscopy and by the presence of an absorption peak around 400 nm in the UV-visible spectrum. Unimodal size distributions of spheroidal nanoparticles were observed by TEM. Greater productivities than those reported by other authors were obtained with the advantage of using a lower temperature and minor reaction times. By using a higher CMC/AgNO3 weight ratio or a higher concentration of AgNO3, AgNPs with larger average size were produced. Antibacterial activity of AgNPs against S. aureus and E. coli was determined by the agar disk diffusion method. The higher the AgNPs concentration, the larger the inhibition zone. The minimum inhibitory concentration (MIC) of AgNPs against S. aureus and E. coli was 5 μg/disk.


2014 ◽  
Vol 23 ◽  
pp. 27-35
Author(s):  
Jyothi Hiremath ◽  
Vandana Rathod ◽  
Shivaraj Ninganagouda ◽  
Dattu Singh ◽  
K. Prema

Nanotechnology is a field that is burgeoning day by day, making an impact in all spheres of human life. Biological methods of synthesis have paved way for the “greener synthesis” of nanoparticles and these have proven to be better methods due to slower kinetics, they offer better manipulation and control over crystal growth and their stabilization. In this context we have investigated extracellular biosynthesis of silver nanoparticles (AgNPs) using cell-free extract of Rhizopus spp.. Formation of AgNPs was indicated by the change in the colour of the cellfree extract from yellow to dark brown under static condition after 48 hrs of incubation. Characterization of AgNPs was carried out by UV-Vis Spectroscopy which gave sharp plasmon resonance peak at 429 nm corresponding to spherical shaped nanoparticles. Transmission electron microscopy (TEM) micrograph showed formation of well-dispersed AgNPs in the range of 25-50 nm. Scanning electron microscopy (SEM) showed the particles to be uniformly dispersed without agglomeration with smooth morphology. EDS showed the presence of elemental silver at 3kev. X-ray diffraction (XRD)-spectrum of the AgNPs exhibited 2θ¸ values corresponding to nanocrystal. These biosynthesized AgNPs were used to study their antimicrobial activity against Multi-drug resistant (MDR) E. coli strains, by Agar diffusion method. Zone of inhibition was measured. Synthesis of nanosized particles with antibacterial properties, which are called "nanoantibiotics", is of great interest in the development of new pharmaceutical products.


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