Chemotaxonomic Study of Six Nigerian Ficus Species (Moraceae)

Cell-free extracts of six strains of Enterococcus species obtained from fermented foods were used for the green synthesis of silver nanoparticles (AgNPs), which was characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The biosynthesized AgNPs were dark brown in colour having surface plasmon resonance in the range of 420-442 nm. The spherical shaped AgNPs had sizes of 4-55 nm, whose formations were facilitated by proteins as indicated by the presence of peaks 1,635-1,637 and 3,275-3,313 cm-1 in the FTIR spectra. The energy dispersive x-ray (EDX) showed prominent presence of silver in the AgNPs colloidal solution, while the selected area electron diffraction was typified by the face-centred crystalline nature of silver. The particles inhibited the growth of multi-drug resistant clinical isolates of Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris, and also potentiated the activities of ampicillin, ciprofloxacin and cefuroxime in the AgNPs-antibiotic synergy studies. In addition, the prospective relevance of the particles as nanopreservative in paints was demonstrated with the inhibition of growth of Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus niger and A. flavus in AgNPs-paint admixture. This report further demonstrates the green synthesis of AgNPs by strains of Enterococcus species.

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Green Synthesis of Silver and Gold Nanoparticles via Sargassum serratifolium Extract for Catalytic Reduction of Organic Dyes

Catalysts ◽

10.3390/catal11030347 ◽

2021 ◽

Vol 11 (3) ◽

pp. 347

Author(s):

Beomjin Kim ◽

Woo Chang Song ◽

Sun Young Park ◽

Geuntae Park

Keyword(s):

Gold Nanoparticles ◽

Green Synthesis ◽

Catalytic Reduction ◽

Organic Dyes ◽

Low Cost ◽

Inorganic Nanoparticles ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Sargassum Serratifolium

The green synthesis of inorganic nanoparticles (NPs) using bio-materials has attained enormous attention in recent years due to its simple, eco-friendly, low-cost and non-toxic nature. In this work, silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were synthesized by the marine algae extract, Sargassum serratifolium (SS). The characteristic studies of bio-synthesized SS-AgNPs and SS-AuNPs were carried out by using ultraviolet–visible (UV–Vis) absorption spectroscopy, dynamic light scattering (DLS), high-resolution transmission electron microscope (HR-TEM), selected area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Phytochemicals in the algae extract, such as meroterpenoids, acted as a capping agent for the NPs’ growth. The synthesized Ag and Au NPs were found to have important catalytic activity for the degradation of organic dyes, including methylene blue, rhodamine B and methyl orange. The reduction of dyes by SS-AgNPs and -AuNPs followed the pseudo-first order kinetics.

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Optimization of biogenic synthesis of silver nanoparticles from flavonoid-rich Clinacanthus nutans leaf and stem aqueous extracts

Royal Society Open Science ◽

10.1098/rsos.200065 ◽

2020 ◽

Vol 7 (7) ◽

pp. 200065 ◽

Cited By ~ 1

Author(s):

Siti Nur Aishah Mat Yusuf ◽

Che Nurul Azieyan Che Mood ◽

Nor Hazwani Ahmad ◽

Doblin Sandai ◽

Chee Keong Lee ◽

...

Keyword(s):

Silver Nanoparticles ◽

Functional Groups ◽

Silver Ions ◽

Cost Effective ◽

Aqueous Extracts ◽

Tem Analysis ◽

Transmission Electron ◽

Vis Spectroscopy ◽

The Face ◽

Clinacanthus Nutans

Background : Silver nanoparticles (AgNPs) are widely used in food industries, biomedical, dentistry, catalysis, diagnostic biological probes and sensors. The use of plant extract for AgNPs synthesis eliminates the process of maintaining cell culture and the process could be scaled up under a non-aseptic environment. The purpose of this study is to determine the classes of phytochemicals, to biosynthesize and characterize the AgNPs using Clinacanthus nutans leaf and stem extracts. In this study, AgNPs were synthesized from the aqueous extracts of C. nutans leaves and stems through a non-toxic, cost-effective and eco-friendly method. Results : The formation of AgNPs was confirmed by UV-Vis spectroscopy, and the size of AgNP-L (leaf) and AgNP-S (stem) were 114.7 and 129.9 nm, respectively. Transmission electron microscopy (TEM) analysis showed spherical nanoparticles with AgNP-L and AgNP-S ranging from 10 to 300 nm and 10 to 180 nm, with average of 101.18 and 75.38 nm, respectively. The zeta potentials of AgNP-L and AgNP-S were recorded at −42.8 and −43.9 mV. X-ray diffraction analysis matched the face-centred cubic structure of silver and was capped with bioactive compounds. Fourier transform infrared spectrophotometer analysis revealed the presence of few functional groups of phenolic and flavonoid compounds. These functional groups act as reducing agents in AgNPs synthesis. Conclusion : These results showed that the biogenically synthesized nanoparticles reduced silver ions to silver nanoparticles in aqueous condition and the AgNPs formed were stable and less toxic.

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Artificial Sweeteners and Sugar Ingredients as Reducing Agent for Green Synthesis of Silver Nanoparticles

Journal of Nanomaterials ◽

10.1155/2019/9641860 ◽

2019 ◽

Vol 2019 ◽

pp. 1-16 ◽

Cited By ~ 4

Author(s):

Shohreh Hemmati ◽

Erin Retzlaff-Roberts ◽

Corren Scott ◽

Michael T. Harris

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Green Synthesis ◽

Reducing Agents ◽

Reducing Agent ◽

Artificial Sweeteners ◽

Silver Nanostructures ◽

Artificial Sweetener ◽

Transmission Electron ◽

Vis Spectroscopy

An environmentally friendly technique has been developed to produce metal nanoparticles using green synthesis methods. In this study, silver nanostructures were synthesized using different sugar substitutes and artificial sweeteners as green reducing agents in an aqueous solution at low temperature. The main ingredients (such as maltodextrin, sucrose, saccharin, and sucralose) of the artificial sweeteners acting as reducing agents were used to reduce Ag+ ions to Ag0. The pH of the solution was controlled during synthesis through the addition of sodium hydroxide (NaOH) to increase the strength of the reducing agents by converting nonreducing sugars to reducing ones and consequently increasing the rate of silver nanoparticle formation. The size and morphology of the synthesized nanostructures were characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The formation of nanostructures during the course of the reactions was investigated by UV-visible (UV-vis) spectroscopy characterization of an aliquot of sample at specific intervals. The function of each artificial sweetener and corresponding ingredients as a reducing agent and capping agent was investigated by Fourier-transform infrared spectroscopy (FTIR) and mass spectrometry (MS).

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Fabrication of TiO2Nanotanks Embedded in a Nanoporous Alumina Template

Journal of Nanomaterials ◽

10.1155/2015/452148 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

C. Massard ◽

S. Pairis ◽

V. Raspal ◽

Y. Sibaud ◽

K. O. Awitor

Keyword(s):

Electron Microscopy ◽

Sol Gel ◽

Thermal Treatments ◽

X Ray Diffraction ◽

Alumina Template ◽

Nanoporous Alumina ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Sol Gel Process

The feasibility of surface nanopatterning with TiO2nanotanks embedded in a nanoporous alumina template was investigated. Self-assembled anodized aluminium oxide (AAO) template, in conjunction with sol gel process, was used to fabricate this nanocomposite object. Through hydrolysis and condensation of the titanium alkoxide, an inorganic TiO2gel was moulded within the nanopore cavities of the alumina template. The nanocomposite object underwent two thermal treatments to stabilize and crystallize the TiO2. The morphology of the nanocomposite object was characterized by Field Emission Scanning Electron Microscopy (FESEM). The TiO2nanotanks obtained have cylindrical shapes and are approximately 69 nm in diameter with a tank-to-tank distance of 26 nm. X-ray diffraction analyses performed by Transmission Electron Microscopy (TEM) with selected area electron diffraction (SAED) were used to investigate the TiO2structure. The optical properties were studied using UV-Vis spectroscopy.

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Green Synthesis of Silver Nanoparticles Using Astragalus tribuloides Delile. Root Extract: Characterization, Antioxidant, Antibacterial, and Anti-Inflammatory Activities

Nanomaterials ◽

10.3390/nano10122383 ◽

2020 ◽

Vol 10 (12) ◽

pp. 2383

Author(s):

Majid Sharifi-Rad ◽

Pawel Pohl ◽

Francesco Epifano ◽

José M. Álvarez-Suarez

Keyword(s):

Silver Nanoparticles ◽

Green Synthesis ◽

Total Phenolics ◽

Cost Effective ◽

Root Extract ◽

Transmission Electron ◽

Vis Spectroscopy ◽

High Efficient ◽

Anti Inflammatory ◽

Average Size

Today, the green synthesis of metal nanoparticles is a promising strategy in material science and nanotechnology. In this research, silver nanoparticles (AgNPs) were synthesized through the high-efficient, cost-effective green and facile process, using the Astragalus tribuloides Delile. root extract as a bioreduction and capping agent at room temperature. UV–Vis spectroscopy was applied for the investigation of the reaction proceedings. To characterize the greenly synthesized AgNPs, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), and transmission electron microscopy (TEM) analyses were utilized. In addition, the total phenolics and flavonoids contents, antioxidant, antibacterial, and anti-inflammatory activities of the greenly synthesized AgNPs and the A. tribuloides root extract were evaluated. The results indicated that the AgNPs had spherical morphology and crystalline structure with the average size of 34.2 ± 8.0 nm. The total phenolics and flavonoids contents of the greenly synthesized AgNPs were lower than those for the A. tribuloides root extract. The resultant AgNPs exhibited the appropriate antioxidant activity (64%) as compared to that for the A. tribuloides root extract (47%). The antibacterial test approved the higher bactericidal activity of the resulting AgNPs on the Gram-positive and Gram-negative bacteria in comparison to the A. tribuloides root extract. Considering the anti-inflammatory activity, the greenly synthesized AgNPs showed a stranger effect than the A. tribuloides root extract (82% versus 69% at 500 μg/mL). Generally, the AgNPs that were fabricated by using the A. tribuloides root extract had appropriate antioxidant, antibacterial, and anti-inflammatory activities and, therefore, can be considered as a promising candidate for various biomedical applications.

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Phyto-fabricated Cr2O3 nanoparticle for multifunctional biomedical applications

Nanomedicine ◽

10.2217/nnm-2020-0129 ◽

2020 ◽

Vol 15 (17) ◽

pp. 1653-1669

Author(s):

Hamza Elsayed Ahmed Mohamed ◽

Shakeeb Afridi ◽

Ali Talha Khalil ◽

Tanzeel Zohra ◽

Muhammad Ali ◽

...

Keyword(s):

Biological Properties ◽

In Vitro Assays ◽

X Ray Diffraction ◽

Potential Measurement ◽

Polio Virus ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy

Aim: The biosynthesis of chromium oxide nanoparticles (Cr2O3 NPs), using Hyphaene thebaica as a bioreductant, for assessment of their potential nanomedicinal applications. Materials & methods: Biosynthesized Cr2O3 NPs were characterized by x-ray diffraction, Fourier-transform infrared spectroscopy, energy dispersive x-ray spectroscopy, scanning and transmission electron microscopy, selected area electron diffraction, UV–Vis spectroscopy and ζ-potential measurement. In vitro assays were used to assess the biological properties of Cr2O3 NPs. Results: Nanoparticles with size approximately 25–38 nm were obtained with a characteristic Cr–O vibration at 417 cm-1. A broad spectrum antimicrobial potential and antioxidant nature is reported. Slight inhibition of polio virus and biocompatibility at low doses was observed. Conclusion: We conclude a multifunctional nature of biogenic Cr2O3 NPs.

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Magnetic and Golden Yogurts. Food as a Potential Nanomedicine Carrier

Materials ◽

10.3390/ma13020481 ◽

2020 ◽

Vol 13 (2) ◽

pp. 481

Author(s):

Víctor Garcés ◽

Ana González ◽

Laura Sabio ◽

Carmen M. Sánchez-Arévalo ◽

Natividad Gálvez ◽

...

Keyword(s):

Electron Microscopy ◽

Lactobacillus Acidophilus ◽

Biomedical Applications ◽

Streptococcus Thermophilus ◽

Deficiency Anemia ◽

Fermented Foods ◽

Hyperthermia Treatment ◽

Digestive Diseases ◽

Transmission Electron ◽

Vis Spectroscopy

Yogurt is one of the most emblematic and popular fermented foods. It is produced by the fermentation of milk lactose by bacteria such as Streptococcus thermophilus and Lactobacillus acidophilus. Magnetic (MNPs) and gold nanoparticles (AuNPs) were incorporated into the exopolysaccharides (EPSs) of these bacteria. The functionalized bacteria were characterized by UV-vis spectroscopy and transmission electron microscopy. A large number of MNPs and AuNPs were bound to the bacterial EPS. Interestingly, the nanoparticles’ (NPs) presence did not affect the bacteria’s capacity to ferment milk and to produce magnetic and golden yogurts. Magnetic and golden yogurts represent the perfect combination of emblematic food and nanoparticles and have a range of potential biomedical applications: use in iron-deficiency anemia, diagnosis and hyperthermia treatment of appropriate digestive diseases, and interest in glamour cuisine.

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Nax−yHyTi2−xFexO4·nH2O nanosheets with lepidocrocite-like layered structure synthesized by hydrothermal treatment of ilmenite sand

Open Chemistry ◽

10.2478/s11532-011-0016-8 ◽

2011 ◽

Vol 9 (3) ◽

pp. 415-421 ◽

Cited By ~ 6

Author(s):

Paula Jardim ◽

Lidija Mancic ◽

Bojan Marinkovic ◽

Olivera Milosevic ◽

Fernando Rizzo

Keyword(s):

Hydrothermal Treatment ◽

Layered Structure ◽

Energy Efficient ◽

Low Cost ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Structure Morphology ◽

Vis Spectroscopy

AbstractNax−yHyTi2−xFexO4·nH2O nanosheets with lepidocrocite-like layered structure were produced through alkaline hydrothermal treatment at very low temperatures (130°C) from ilmenite sand. The crystal structure, morphology and optical properties were investigated by X-Ray diffraction, transmission electron microscopy, selected area electron diffraction, energy dispersive spectroscopy and UV-Vis spectroscopy. The product shows leaf-like nanosheet morphology with thickness <30 nm and lengths <1 µm. Three lepidocrocite-like titanates (Imm2 space group) with similar a and c lattice parameters but different interlayer distances (b/2) were identified. This appears to be the first preparation of lepidocrocite-like layered nanosheets by a simple, energy efficient (low temperature) and low cost (starting from mineral sand) procedure.

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Biosynthesis and Characterization of Gold and Silver Nanoparticles Using Milk Thistle (Silybum marianum) Seed Extract

Journal of Nanoscience ◽

10.1155/2014/905404 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 12

Author(s):

R. Gopalakrishnan ◽

K. Raghu

Keyword(s):

Silver Nanoparticles ◽

Seed Extract ◽

Milk Thistle ◽

X Ray Diffraction ◽

Silybum Marianum ◽

Gold And Silver Nanoparticles ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy

Biogenic synthesis of gold and silver nanoparticles from aqueous solutions using milk thistle (Silybum marianum) seed extract as reducing and stabilizing agent has been reported. Formation and stabilization of nanoparticles were monitored using surface plasmon resonance (SPR) bands of UV-Vis spectroscopy. Morphology of gold and silver nanoparticles was investigated using X-ray diffraction, high-resolution transmission electron microscopy with selected area electron diffraction analysis, and dynamic light scattering. Fourier transform-infrared spectroscopy was employed to identify the possible biomolecules responsible for the reduction and stabilization of nanoparticles.

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