scholarly journals Antibacterial and Antioxidant Studies of Green Synthesized Silver Nanoparticles using Azadirachta indica (Neem) Leaf Extract

2021 ◽  
Vol 9 (3) ◽  
pp. 220-226
Author(s):  
Bishow Regmi ◽  
Tirtha Raj Binadi ◽  
Sarb Narayan Jha ◽  
Rajib Kumar Chaudhary ◽  
Bhoj Raj Poudel ◽  
...  

Silver nanoparticles (AgNPs) have been synthesized by green synthesis using Azadirachta indica leaf extract as both reducing and stabilizing agent. Synthesis of colloidal AgNPs was monitored by UV- visible spectroscopy. The UV- visible spectrum showed a peak at 455 nm corresponding to the plasmon absorbance of the silver nanoparticles. Crystallite structure of silver nanoparticles was studied using X-ray diffraction (XRD) analysis which revealed the face-centered cubic structure (FCC) with average particle size of 8.9 nm, calculated using Debye-Scherrer’s equation. Transmission electron microscopy (TEM) image revealed the agglomeration of small grain with particle size ranging from 2 to 14 nm. FCC crystalline nature was also evident from selected area electron diffraction (SAED) analysis. High purity of as-synthesized AgNPs was analyzed using energy dispersive X-ray (EDX) spectroscopy. Band gap energy was calculated to be 2.7 eV from UV- Visible spectra. 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was stabilized by AgNPs which reveals its antioxidant efficacy. Well diffusion method showed 7 mm to 12 mm zone of inhibition (ZOI) against Gram-positive and Gram-negative bacteria, respectively confirming the antibacterial potential of AgNPs. Int. J. Appl. Sci. Biotechnol. Vol 9(3): 220-226.

2021 ◽  
Author(s):  
C. Nirmala ◽  
M Srid

Abstract Endophyte mediated nanoparticles fabrication was emerging as a new frontier in nanomedicines that produce high biocompatible and functionalized silver nanoparticles. In this study, silver nanoparticles were successfully biosynthesized from the extracellular extract of endophytic bacterium Pantoea anthophila isolated from the stem of Waltheria indica for the first time. The synthesised nanoparticles were characterized by UV-Visible and Fourier Transform Infra-Red spectroscopy. The structural analysis is done by X-ray diffraction and the stability was studied by dynamic light scattering and particle size analyser. The size and shape were observed by Transmission Electron Microscope, Scanning Electron Microscope and Energy Dispersive X-Ray spectrum. Further, the nanoparticles were evaluated for antimicrobial and antioxidant properties. Synthesized nanoparticle showed a strong absorption band in the UV-Visible range at 410 nm. The average particle size was found to be 16.8 nm with spherical shaped, crystalline nature. Good zones of inhibition at various ranges were detected against a broad range of human pathogenic bacteria and fungi. A strong free radical scavenging activity of silver nanoparticles with IC50 values 30.75, 19.47, 34.59, 41.12, 27.24, 28.16, 36.21 µg/ml was obtained that was comparable to the reference. The study suggests that the silver nanoparticles can be biosynthesised from endophytic P. anthophila metabolites with significant therapeutic potential. With proper validation, the biosynthesised silver nanoparticles can be developed as a promising antiviral and anticancer drug candidate.


2019 ◽  
Vol 7 (1) ◽  
pp. 51-60
Author(s):  
Paulina Taba ◽  
Nadya Yuli Parmitha ◽  
Syahruddin Kasim

Silver nanoparticles have been synthesized by the reduction method using salam leaf extract (Syzygium polyanthum) as a reducing agent. The silver nanoparticles produced were then tested for their activity as antioxidants. The formation of silver nanoparticles was carried out by adding the leaf extract into the solution of AgNO3 and homogenized using a magnetic stirrer. A UV-Vis spectrophotometer was used to confirm the formation of silver nanoparticles. Particle Size Analyzer (PSA), Scanning Electron Microscope (SEM), X-Ray Diffractometer (XRD) and Fourir Transform Infra Red (FTIR) spectrometers were used to characterize the nanoparticles produced before being tested for antioxidant activity. The results showed that the absorbance value increased with increasing reaction contact time. The maximum uptake was obtained at wavelengths of 432-446 nm using a UV-Vis spectrophotometer. The particle size was determined using a PSA with an average particle size distribution of 45.7 nm. The average diameter of silver nanoparticles was 10.06 – 13.97 nm and the silver nanoparticles had rod-shapes. Functional groups that play a role in the synthesis of nanoparticles were –OH, –C=O, and –C-O groups. Silver nanoparticles inhibited free radicals as antioxidants with the IC50 value of 582.7 ppm.


Author(s):  
B. Anandh ◽  
A. Muthuvel ◽  
M. Emayavaramban

The present investigation demonstrates the formation of silver nanoparticles by the reduction of the aqueous silver metal ions during exposure to the Lagenaria siceraria leaf extract. The synthesized AgNPs have characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) techniques. AgNPs formation has screened by UV-visible spectroscopy through colour conversion due to surface plasma resonance band at 427 nm. X-ray diffraction (XRD) confirmed that the resulting AgNPs are highly crystalline and the structure is face centered cubic (fcc). FT-IR spectrum indicates the presence of different functional groups present in the biomolecules capping the nanoparticles. Further, inhibitory activity of AgNPs and leaf extract were tested against human pathogens like gram-pastive (Staphylococcus aureus, Bacillus subtilis), gram-negative (Escherichia coli and Pseudomonas aeruginosa). The results indicated that the AgNPs showed moderate inhibitory actions against human pathogens than Lagenaria siceraria leaf extract, demonstrating its antimicrobial value against pathogenic diseases


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Indrawati Patabang ◽  
Syahruddin Kasim ◽  
Paulina Taba

Silver nanoparticles have been synthesized using kluwak leaf extract (Pangium edule Reinw) as bioreductor and antioxidant activity assay. The nanoparticles formed were monitored by observing UV-Vis absorption and characterized by using FTIR, PSA, XRD and SEM instruments. The result of functional group characterization with FTIR show that the functional groups OH, C = O, C-O and CH2 act as Ag+ reducing agent. The size of silver nanoparticles was determined by using Particle Size Analyzer (PSA) and the result show average particle size distribution of 93.2 nm. Morphology of AgNp were observed by Scanning Electron Microscope (SEM) and X-Ray Difraction (XRD) analysis show result of 51,78 nm. The antioxidant activity was shown by in kluwak leaf extract and silver nanoparticles with IC50 values respectively 831,33 ppm dan 1493,09 ppm.


2015 ◽  
Vol 1107 ◽  
pp. 301-307 ◽  
Author(s):  
Salahudeen A. Gene ◽  
Elias B. Saion ◽  
Abdul Halim Shaari ◽  
Mazliana A. Kamarudeen ◽  
Naif Mohammed Al-Hada

The fabrication of nanospinel zinc chromite (ZnCr2O4) crystals by the means of thermal treatment method from an aqueous solution containing metal nitrates, polyvinyl pyrrolidone (PVP), and deionized water was described in this study. The samples were calcined at various temperatures ranging from 773 to 973 K for the decomposition of the organic compounds and crystallization of the nanocrystals. PVP was used as capping agent to control the agglomeration of the particles. The characterization studies of the fabricated samples were carried out by X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), energy dispersed X-ray spectroscopy (EDX) and electron spin resonance spectroscopy (ESR). The corresponding peaks of Zn, Cr and O were observed in the EDX spectrum of the sample which confirms the formation of ZnCr2O4. The XRD patterns also confirmed the formation of the single faced nanocrystallines of spinel ZnCr2O4 with a face-centered cubic structure. The average particle size of the synthesized crystals was also determined from the XRD patterns using the Scherers formula which shows that the crystallite sizes increases with increase in calcination temperature and was in good agreement with the TEM images which shows cubical ZnCr2O4 nanocrystals with uniform morphology and particle size distributions. The ESR spectra confirmed the existence of unpaired electron in the fabricated samples and the increase in g-factor and decreases in resonant magnetic field (Hr) were observed as the calcination temperature increases.


2020 ◽  
Vol 9 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Samaira Yasmin ◽  
Shazia Nouren ◽  
Haq Nawaz Bhatti ◽  
Dure Najaf Iqbal ◽  
Shan Iftikhar ◽  
...  

AbstractCurrently, the green route for synthesis of silver nanoparticles (Ag NPs) using plants leaf extract is an emerging research area in nanotechnology. The present study was explored for synthesis, characterization and catalytic application of Ag NPs using Diospyros lotus fresh leaf extracts. Factors affecting the synthesis were optimized and optimum conditions were pH of 8.6, silver nitrate (AgNO3) concentration of 1.5 mM and 10 mL leaf extract. Formation of Ag NPs was observed by change in color of reaction mixture from pale yellow to reddish brown. The synthesized Ag NPs were characterized using UV-Vis spectrophotometer, EDX, XRD and SEM analyses. UV-Vis spectrophotometer showed maximum absorbance peak in the range of 407 nm at different time intervals indicating formation of Ag NPs. SEM and XRD analysis confirmed face centered cubic structure and crystalline nature of biologically synthesized Ag NPs with average particle size of 27 nm. The purity of synthesized Ag NPs was revealed by EDX. Finally, photo catalytic activity (PCA) of Ag NPs was studied and 72.91% decolorization of industrial waste water was obtained at 54 h. Some important parameters like pH, turbidity, conductance; TSS, TDS, sulphide, sulphates, etc. were also monitored before and after treatment with Ag NPs.


2015 ◽  
Vol 29 (06n07) ◽  
pp. 1540047 ◽  
Author(s):  
S. U. Ekar ◽  
Y. B. Khollam ◽  
P. M. Koinkar ◽  
S. A. Mirji ◽  
R. S. Mane ◽  
...  

Present study reports the biochemical synthesis of silver nanoparticles ( Ag -NPs) from aqueous medium by using the extract of medicinal mushroom Ganoderma, as a reducing and stabilizing agents. The Ag -NPs are prepared at room temperature by the reduction of Ag+to Ag in aqueous solution of AgNO3. The resultant particles are characterized by using UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) measurement techniques. The formation of Ag -NPs is confirmed by recording the UV-visible absorption spectra for surface plasmon resonance (SPR) where peak around 427 nm. The prominent changes observed in FTIR spectra supported the reduction of Ag+to Ag . The morphological features of Ag -NPs are evaluated from HRTEM. The spherical Ag -NPs are observed in transmission electron microscopy (TEM) studies. The particle size distribution is found to be nearly uniform with average particle size of 2 nm. The Ag -NPs aged for 15, 30, 60 and 120 days showed no profound effect on the position of SPR peak in UV-visible studies, indicating the protecting/capping ability of medicinal mushroom Ganoderma in the synthesis of Ag -NPs.


2021 ◽  
Vol 11 (10) ◽  
pp. 4638
Author(s):  
Jose Luis López-Miranda ◽  
Rodrigo Esparza ◽  
Marlen Alexis González-Reyna ◽  
Beatriz Liliana España-Sánchez ◽  
Angel Ramon Hernandez-Martinez ◽  
...  

This work reports, for the first time, the synthesis of silver nanoparticles using extracts of the species of Sargassum natans and Sargassum fluitans (AgNPs-S). Their antibacterial and catalytic properties are compared with silver nanoparticles obtained by chemical synthesis (AgNPs-C). The characterization of AgNPs-S and AgNPs-C was carried out using ultraviolet–visible spectroscopy (UV–Vis), dynamic light scattering (DLS), zeta potential, a scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis. The synthesis of silver nanoparticles using Sargassum extract was optimized through varying experimental parameters, such as the type of solvent used to prepare the extract, the volume of the extract, and the pH of the system. The most efficient sample (AgNPs-S) was prepared with a water–ethanol-based extract, using a 3:1 volumetric ratio of extract: a precursor salt with the addition of 1 mL of NaOH pH = 14. The AgNPs-C were spherical in shape, with an average particle size of 11.55 nm, while the AgNPs-S were polyhedral shaped, with an average particle size of 26.39 nm. The synthesized AgNPs-S were found to have significantly higher catalytic activity for the degradation of methylene blue and more effective antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa than AgNPs-C.


2013 ◽  
Vol 1 (04) ◽  
pp. 16-24 ◽  
Author(s):  
Anu Kumar ◽  
Kuldeep Kaur ◽  
Sarika Sharma

The present study reports the synthesis of silver nanoparticle using Morus nigra leaf extract were used as reducing agent for reduction of silver nitrate solution. The synthesis of silver nanoparticles was analyzed by UV-Visible spectroscopy, Scanning Electron Microscopy. The SEM analysis has shown that size of silver nanoparticles synthesized from leaves extract of M.nigra was 200 nm and seems to be spherical in morphology. Morphology of chemically synthesized silver nanoparticles is nearly spherical and of size ranges from 300-500 nm. The average particle size analyzed from SEM analysis was observed to be 350 nm. This article has discussed the synthesis of silver nanoparticles generated from plant extract, characterization and antibacterial analysis. In this study the antibacterial activity was examined against six MTCC cultures collected from IMTECH Chandigarh, Including both gram positive and gram negative bacteria such as P.aeruginosa, S.aureus, B.subtilis, E.coli, P.flourescens and Streptococus mutans. Out of these strains the antimicrobial activity of the silver nanoparticles showed maximum zone of inbhition against P.flourescens (22 mm), P.aeruginosa (19 mm), S.aureus (18 mm) and least effective against E.coli (15mm). In contrast chemically synthesized silver nanoparticles were found most effective against S.aureus (13 mm) and B.subtilis (12mm) and almost ineffective against Streptococcus mutans (6 mm) and P.flourescens (4 mm). In the concluding remarks, the silver nanoparticles synthesized using M.nigra leaves extract would be a better antimicrobial effective against various bacterial species.


2009 ◽  
Vol 2009 ◽  
pp. 1-5 ◽  
Author(s):  
Mingru Zhou ◽  
Zhiqiang Wei ◽  
Hongxia Qiao ◽  
Lin Zhu ◽  
Hua Yang ◽  
...  

In the protecting inert gas, silver nanoparticles were successfully prepared by confined arc plasma method. The particle size, microstructure, and morphology of the particles by this process were characterized via X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED). TheN2absorption-desorption isotherms of the samples were measured by using the static volumetric absorption analyzer, the pore structure of the sample was calculated by Barrett-Joyner-Halenda (BJH) academic model, and the specific surface area was calculated from Brunauer-Emmett-Teller (BET) adsorption equation. The experiment results indicate that the crystal structure of the samples is face-centered cubic (FCC) structure the same as the bulk materials, the particle size distribution ranging from 5 to 65 nm, with an average particle size about 26 nm obtained by TEM and confirmed by XRD and BET results. The specific surface area is 23.81 m2/g, pore volumes are 0.09 cm3/g, and average pore diameter is 18.7 nm.


Sign in / Sign up

Export Citation Format

Share Document