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Yttrium oxide (Y2O3) is a promising rare-earth compound that is rarely studied. This study reports on the synthesis, structural, morphological, optical and antimicrobial properties of Y2O3 nanoparticles (NPs) synthesized using Agathosma betulina leaf extract. XRD pattern indicated that the crystalline phase was achieved for the sample calcined at 5 0 0 ∘ C with body-centered cubic symmetry. SEM and TEM images of Y2O3 nanopowder showed the nearly spherical morphology of agglomerated NPs with an average diameter of 13 nm. Optical properties revealed that the bandgap of Y2O3 NPs (∼ 5. 6 7 eV) has been increased compared with the bulk Y2O3 (∼ 5. 5 eV). Moreover, the antimicrobial activity was also evaluated against gram-positive and gram-negative bacteria of clinical interest. Results demonstrated that the synthesized Y2O3 NPs exhibited higher bacteriostatic effects against gram-negative bacterial strains due to their thin cell wall structure. These results show that the synthesized Y2O3 NPs are suitable for antibacterial control systems and medicines. [ABSTRACT FROM AUTHOR]

Green synthesis employs environmentally friendly, biodegradable substances for the production of nanomaterials. This study aims to develop an innovative method for synthesizing silver nanoparticles (AgNPs) using a methanolic extract of Fomes fomentarius L. Fr. as the reducing agent and to assess the potential antibacterial properties of the resulting nanoparticles. The successful synthesis of AgNPs was confirmed through characterization techniques such as UV-visible (UV-Vis) spectrophotometry, Fourier-transform infrared spectroscopy (FT-IR), and powder X-ray diffraction (PXRD). The UV-Vis analysis revealed an absorption peak at 423 nm, while FT-IR identified key phytochemical compounds involved in the reduction process. PXRD analysis indicated a face-centered cubic (fcc) structure with prominent peaks observed at 2θ = 38°, 44.6°, 64.6°, and 78°, confirming the crystalline nature of the AgNPs, with a crystallite diameter of approximately 24 nm, consistent with TEM analysis. The synthesized AgNPs demonstrated significant antibacterial activity, particularly against S. aureus, with higher efficacy against gram-positive bacteria. [ABSTRACT FROM AUTHOR]

In this research, we employed a microwave-assisted green synthesis method utilizing extracts from Cistus salviifolius L. and Ferula communis L. to synthesize silver nanoparticles (AgNPs). Subsequently, we characterized the biosynthesized AgNPs, both Cs-AgNPs (derived from C. salviifolius) and Fc-AgNPs (derived from F. communis), through UV-Vis, FT-IR, XRD, SEM, and TEM analyses. The AgNPs exhibited a spherical shape with sizes averaging below 11 nm. To assess their antioxidant activity, we employed the DPPH method. Furthermore, we examined the antimicrobial potential of Cs-AgNPs and Fc-AgNPs against pathogenic bacterial strains, including Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli, using the disc diffusion assay and minimum inhibitory concentration. Additionally, we evaluated the cytotoxic effects of Cs-AgNPs and Fc-AgNPs on various cell lines, namely breast adenocarcinoma (MCF-7), colon carcinoma (HT-29), human keratinocytes (HaCaT), and embryonic kidney (HEK-293), employing the Alamar Blue assay. Our findings indicate that the biosynthesized Cs-AgNPs and Fc-AgNPs possess antioxidant, antibacterial, and anticancer activities. Therefore, the current study suggests that Cs-AgNPs and Fc-AgNPs exhibit potential for treating cancer and diseases caused by pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Silver Oxide nanoparticles (AgONPs) have been revealed to have many applications, including antibacterial behavior. However, the conventional methods for synthesizing AgO NPs often use toxic chemicals that may be detrimental to human health and environmental factors. The crystalline structure and size of obtained AgO NPs were confirmed by Powder X-ray diffraction analysis with 35–70 nm. Functional groups have been identified in Fourier transform infrared spectroscopy. The result of Energy Dispersive X-ray Spectroscopy confirmed the presence of the elements in the synthesized AgO NPs. The energy band gap is determined using UV–visible spectroscopy. Morphological examination of prepared AgO NPs, comprising spherical and rod-like structures, was performed using a Transmission, and scanning electron microscope. The antibacterial activity was evaluated using Gram-negative (Klebsiella pneumonia, Escherichia coli) and Gram-positive (Staphylococcus aureus, Bacillus cereus) bacteria from Agar Well Diffusion Method. The results show that the green synthesis of AgO NPs have better antibacterial activity. The inhibition zone diameter were observedfor all microorganisms. The green synthesis of AgO NPs from herbal plant leaf extracts is a promising method for developing safe and effective antibacterial agents. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were biosynthesized from Alternanthera philoxeroides leaf extract. Green synthesis of silver nanoparticles was done by mixing plant extract with AgNO3 solutions. Surface plasmon resonance and energy dispersive X-ray spectroscopy data revealed the formation of AgNPs. X-Ray beam diffraction data provided information about the crystalline nature of synthesized silver nanoparticles. Fourier transform infrared spectroscopy ratified the presence of an amine phenolic, higher degree of unsaturation, and protein-containing biomolecules, which were responsible for the reduction and capping of nanoparticles during synthesis. Field emission scanning electron microscopy data revealed the spherical morphology of synthesized AgNPs. High-resolution transmission electron microscopy study of the nanoparticles suggested its almost spherical structure with sizes ranging from 7.4 to 35.6 nm with a median particle size of 14.63 nm. Antioxidant activity was studied by DPPH assay method, while antibacterial activity was conducted by using the agar well diffusion method against Escherichia coli, Staphylococcus aureus, Salmonella abony, and Bacillus subtilis. The results showed that the antioxidant and antibacterial properties of AgNPs are higher than those of plant extract, which shows its potential use in biomedical applications. [ABSTRACT FROM AUTHOR]

The present study focused on evaluating the antibacterial properties, radical scavenging, and photocatalytic activities of Centaurea behen-mediated silver nanoparticles (Cb-AgNPs). The formation of Cb-AgNPs was approved by UV–Vis spectrometry, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy (SEM), energy dispersive X-ray and X-ray diffraction. The results showed that the obtained AgNPs have a maximum absorbance peak at 450 nm with spherical morphology and an average size of 13.03 ± 5.8 nm. The catalytic activity of the Cb-AgNPs was investigated using Safranin O (SO) solution as a cationic dye model. The Cb-AgNPs performed well in the removal of SO. The coupled physical adsorption/photocatalysis reaction calculated about 68% and 98% degradation of SO dye under solar irradiation. The Cb-AgNPs inhibited the growth of gram-negative or positive bacteria strains and had excellent DPPH radicals scavenging ability (100% in a concentration of 200 µg/ml) as well as a good effect on reducing coagulation time (at concentrations of 200 and 500 µg/mL reduced clotting time up to 3 min). Considering the fact that green synthesized Cb-AgNPs have antioxidant and antibacterial properties and have a good ability to reduce coagulation time, they can be used in wound dressings. As well as these NPs with good photocatalytic activity can be a suitable option for degrading organic pollutants. [ABSTRACT FROM AUTHOR]

Pomegranate waste poses an environmental challenge in Arequipa. Simultaneously, interest in sustainable materials like natural rubber latex (NRL) is growing, with Peruvian communities offering a promising source. This study explores the green synthesis of silver nanoparticles (AgNPs) using pomegranate peel extract and their incorporation into NRL nanofibers for enhanced functionalities. An eco-friendly process utilized silver nitrate and pomegranate peel extract as a reducing and capping agent to synthesize AgNPs. The resulting AgNPs and NRL/AgNPs nanofibers were characterized using imaging and spectroscopic techniques such as UV-vis, TGA, FTIR, XRD, Raman, SEM, and DLS. Green-synthesized AgNPs were spherical and crystalline, with an average diameter of 59 nm. They showed activity against K. pneumoniae, E. coli, B. cereus, and S. aureus (IC50: 51.32, 4.87, 27.72, and 69.72 µg/mL, respectively). NRL and NRL/AgNPs nanofibers (300–373 nm diameter) were successfully fabricated. The composite nanofibers exhibited antibacterial activity against K. pneumoniae and B. cereus. This study presents a sustainable approach by utilizing pomegranate waste for AgNP synthesis and NRL sourced from Peruvian communities. Integrating AgNPs into NRL nanofibers produced composites with antimicrobial properties. This work has potential applications in smart textiles, biomedical textiles, and filtration materials where sustainability and antimicrobial functionality are crucial. [ABSTRACT FROM AUTHOR]

Summary: The biological synthesis of functionalised nanoparticles using plant materials is considered more cost‐effective and eco‐friendly than chemical and physical methods. Hence, this study demonstrated the synthesis of silver nanoparticles (AgNPs) using Houttuynia cordata Thunb rhizome (HCR). The extract, prepared with distilled water, provided the required phytochemical components, such as flavonoids, terpenoids, phenols, proteins and other essential bio‐reducing agents. The AgNPs were exposed to reaction conditions, such as temperatures, pH values and AgNO3 concentrations, to identify the optimum synthesis condition and explore their impacts on particle size and antibacterial action against Gram‐positive (Staphylococcus aureus) and Gram‐negative (Salmonella enterica and Shigella dysenteriae) foodborne pathogens. The formation of AgNPs was indicated by specific surface plasmon resonance (SPR) intensity at 440–450 nm and colour changes under different reaction conditions. The structure and size distribution characterised by SEM and TEM revealed that the AgNPs exhibited a spherical‐shaped structure with irregular contours, regular distribution and aggregation. Although the average particle size ranged from 2 to 100 nm, relatively smaller sizes were detected at 10 mM (54.30), 80 °C (49.50 nm) and pH 6 (60.16 nm) conditions. The FTIR spectrum and EDX spectral signals affirmed the presence of reducing and stabilising agents in HCR extract, following the reduction of AgNPs from Ag+ to Ag0. AgNPs also exhibited excellent antibacterial activity against S. aureus, S. enterica and Sh. dysenteriae, indicating a broad spectrum for various applications in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

This study defined a facile, inexpensive, and benign method to fabricate silver nanoparticles (AgNPs) using Tradescantia pallidum var. purpurea aqueous leaves extract for the first time. A UV–vis spectrum showed that the evaluated extract was promising for green synthesis of the SNP, with the highest peak of absorption between 450 and 550 nm. The phytochemicals present in the plant extract acts as capping and stabilization agent were confirmed by FTIR analysis. EDX proved the presence of Ag while SEM confirmed the AgNPs with the spherical shape. TEM revealed the average particle size was 23 nm. Additionally, AgNPs exhibited significant antibacterial activity and turbidimetry analysis showed MIC and MBC was in range of 25–100 µg/mL against both Gram positive and Gram-negative bacteria in Luria Bertani broth cultures. The AgNPs exhibited potent antibacterial activity against gram-positive bacteria, with a ZOI of 12 ± 0.25 mm produced against BacillusB subtilis showed the largest zones of inhibition, which were greater than the positive control (cefotaxime). The MIC values were 50 µg/mL for Pseudomonas aeruginosa, 25 µg/mL for Staphylococcus aureus and Escherichia coli, and 100 µg/mL for B. subtilis, confirming their significant antibacterial action. AgNPs inhibited the DDPH free radical scavenging activity with an IC50 = 91.87 µg/mL. It is believed that these AgNPs play a crucial role in determining the therapeutic potential of T. pallida due to their biological efficacy. [ABSTRACT FROM AUTHOR]

Objectives: Silver nanoparticles (AgNPs) are gaining increasing attention in biomedical applications due to their unique properties. Green synthesis methods are environmentally friendly and have demonstrated potential for AgNP production. This study explores the green synthesis of AgNPs using the methanolic extract of Euphorbia milii, a plant known for its medicinal properties. The primary objectives of this research were to synthesize AgNPs using E. milii extract, characterize the nanoparticles (NPs) using various techniques, and evaluate their antibacterial and enzyme inhibitory activities. Methods: E. milii plant extract was utilized for the green synthesis of AgNPs. The characterization of the NPs was performed through ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDX). Antibacterial activity was assessed against Staphylococcus aureus, while enzyme inhibitory assays were conducted against urease, α-glucosidase, carbonic anhydrase II, and xanthine oxidase. Results: The synthesized AgNPs exhibited significant antibacterial effects, with a remarkable 20-mm zone of inhibition against S. aureus, surpassing the efficacy of the plant extract alone. Furthermore, the AgNPs demonstrated remarkable enzyme inhibition, achieving impressive percentages of 77.98% against α-glucosidase and 88.54% against carbonic anhydrase II. Half-maximal inhibitory concentration values for enzyme inhibition were highly promising, including 78.09 ± 1.98 µM for α-glucosidase, 0.22 ± 0.10 µM for carbonic anhydrase II, and 7.11 ± 0.55 µM for xanthine oxidase. Conclusion: In this study, AgNPs were successfully synthesized using E. milii extract and characterized using various techniques. The AgNPs exhibited significant antibacterial and enzyme-inhibitory activities, showcasing their potential for biomedical applications. [ABSTRACT FROM AUTHOR]

Antimicrobial natural polymer film with silver nanoparticles (AgNPs) biosynthesized using aqueous plant root extracts as reducing capping agents and for film formatting show extensive applicability for pathogenic microorganism problems. The formation of AgNPs was confirmed by transmission electron microscopy (TEM) and scanning electron microscopy–energy-dispersive spectroscopy (SEM–EDS) techniques. The antimicrobial activity of biofilm with green AgNPs was analysed by inhibiting the growth of Gram-negative and Gram-positive bacteria culture using the Kirby–Bauer disk diffusion susceptibility test. Total phenolic content and antioxidant activity were slightly higher in aqueous extracts of Sym. Radix than in Sym. Radix/AgNPs. The antimicrobial effect of polymer film/AgNPs against selected test bacteria cultures was substantially more robust than with pure film. Pictures of AgNPs obtained by TEM revealed the presence of spherical-shaped nano-objects with an average size 27.45 nm. SEM–EDS studies confirmed the uniform distribution of metal nanoparticles throughout the biopolymeric matrix. Morphological studies of the surface showed that the obtained surface of the films was even, without holes or other relief irregularities. These apparent Symphyti radix polymer film/AgNPs' biological functions could provide a platform for fighting pathogenic bacteria in the era of multi-drug resistance. [ABSTRACT FROM AUTHOR]

The green synthesis of silver nanoparticles (AgNPs) using the cell-free supernatant of a Haematococcus pluvialis culture (CFS) was implemented in the current study, under illumination conditions. The reduction of Ag+ to AgNPs by the CFS could be described by a pseudo-first-order kinetic equation at the temperature range tested. A high reaction rate during synthesis and stable AgNPs were obtained at 45 °C, while an alkaline pH (pH = 11.0) and a AgNO3 aqueous solution to CFS ratio of 90:10 (v/v) proved to be the most effective conditions in AgNPs synthesis. A metal precursor (AgNO3) at the concentration range tested (1–5 mM) was the limited reactant in the synthesis process. The synthesis of AgNPs was accomplished under static and agitated conditions. Continuous stirring enhanced the rate of reaction but induced aggregation at prolonged incubation times. Zeta potential and polydispersity index measurements indicated stable AgNPs and the majority of AgNPs formation occurred in the monodisperse phase. The X-ray diffraction (XRD) pattern revealed the face-centered cubic structure of the formed AgNPs, while TEM analysis revealed that the AgNPs were of a quasi-spherical shape with a size from 30 to 50 nm. The long-term stability of the AgNPs could be achieved in darkness and at 4 °C. In addition, the synthesized nanoparticles showed antibacterial activity against Escherichia coli. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (AgNPs) has attracted substantial interest and achievement due to their environmental friendliness, ease of manipulation, and potential for large-scale production. By using aqueous Camellia sinensis leaf extract, suspensions of AgNPs, which possess photocatalytic and biological activity, were successfully synthesized in this study. The reduction of silver ions to AgNPs was visually inspected via the colour of the reaction mixture, which was altered from pale yellow to reddish brown. The methods of characterization of the as-synthesized AgNPs were performed using Ultraviolet-Visible spectroscopy (UV-Vis), dynamic light scattering technique (DLS), and X-ray diffraction analysis (XRD). The surface plasmon resonance bands of AgNPs at 420-430 nm in UV-Vis spectra indicated the presence of silver particles at the nanoscale. The size of AgNPs was determined by DLS, ranging from 25 nm to 40 nm. XRD analysis showed that AgNPs were highly pure and crystalline. The antibacterial activity of AgNPs against Gram-positive and Gram-negative bacterial strains, including Staphylococcus aureus and Escherichia coli, respectively, was demonstrated by the disc diffusion method. The examination of the photocatalytic activity of AgNPs was conducted through methylene blue (MB) degrading experiments, and the MB degrading performance was approximately 95% within 72 h under sunlight. [ABSTRACT FROM AUTHOR]

The investigation of using medicinal plants for the production and application of silver nanoparticles (AgNPs) has attracted growing research interest. In this study, AgNPs are synthesized from the stem barks of the Pyrus pashia medicinal plant using a biosynthetic strategy. The reaction conditions were optimized under ambient conditions, including concentration, temperature, time, and pH, and various techniques were employed, such as UVvisible, FTIR, XRD, FESEM, and TEM, to characterize the synthesized AgNPs. The AgNPs produced through this biosynthesis method were found to be spherical and polydispersed, with an average size of 23.92 ± 7.04 nm. The synthesized AgNPs demonstrated an enhanced DPPH free radical scavenging capacity compared to the aqueous extract, with IC50 values of 10.67 ± 0.05 µg/mL and 13.66 ± 0.35 µg/mL, respectively. In the agar well diffusion method, the synthesized AgNPs showed higher antibacterial activity than that of the extract against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Salmonella typhi (ATCC 14028), and Shigella sonnei (ATCC 25931). Based on these findings, the study suggests that green synthesized AgNPs from P. pashia could be used for biomedical applications. [ABSTRACT FROM AUTHOR]

The era of increasing bacterial antibiotic resistance requires new approaches to fight infections. With this purpose, silver-based nanomaterials are a reality in some fields and promise new developments. We report the green synthesis of silver nanoparticles (AgNPs) using culture broths from a microalga. Broths from two media, with different compositions and pHs and sampled at two growth phases, produced eight AgNP types. Nanoparticles harvested after several synthesis periods showed differences in antibacterial activity and stability. Moreover, an evaluation of the broths for several consecutive syntheses did not find relevant kinetics or activity differences until the third round. Physicochemical characteristics of the AgNPs (core and hydrodynamic sizes, Z-potential, crystallinity, and corona composition) were determined, observing differences depending on the broths used. AgNPs showed good antibacterial activity at concentrations producing no or low cytotoxicity on cultured eukaryotic cells. All the AgNPs had high levels of synergy against Escherichia coli and Staphylococcus aureus with the classic antibiotics streptomycin and kanamycin, but with ampicillin only against S. aureus and tetracycline against E. coli. Differences in the synergy levels were also dependent on the types of AgNPs. We also found that, for some AgNPs, the killing of bacteria started before the massive accumulation of ROS. [ABSTRACT FROM AUTHOR]

A green, economical, highly efficient and easy method for the synthesis of AgNPs using dried black mulberry (Morus nigra L.) fruit extract was reported. Their formations were confirmed by both its brown color and the plasmon resonance band. The TEM analysis showed that they were in spherical shape with an average size of 6 ± 1 nm. In addition, they have exhibited excellent antibacterial activities against eleven different pathogenic bacteria. Finally, they have showed advanced catalytic activity against to methyl orange (MO), cresol red (CR) and methylene blue (MB) dyes both in unary and ternary mixture of dyes. In addition, the degradation of ternary dye mixture using the synthesized AgNPs was also tested using wastewater as the real sample. [ABSTRACT FROM AUTHOR]

The use of plant extracts to produce metal particles at the nanoscale has attracted intensive research interest due to their cost-effectiveness and eco-friendliness. This study aimed to investigate the synthesis of silver nanoparticles (AgNPs(using aqueous extracts of Silybum marianum L. and Portulaca oleracea L. and to assess their effectiveness as antibacterial and antifungal agents using the agar-well diffusion method. The production of AgNPs was confirmed through spectrophotometry, and their size and shape were measured using Transmission Electron Microscopy (TEM). The role of organic compounds in nanoparticle synthesis was also explored through Fourier Transform Infrared Spectroscopy (FTIR). The FTIR analysis identified the functional groups of organic compounds in S. marianum and P. oleracea extracts that were responsible for reducing Ag ions and capping the resulting AgNPs. The nanoparticles demonstrated potent antimicrobial properties against Escherichia coli, Staphylococcus aureus, Fusarium graminearum, and Alternaria alternata. It was concluded that, in addition to their unique medicinal properties, S. marianum and P. oleracea can be utilized in the production of AgNP for medical and pharmaceutical purposes against Gram-positive and Gram-negative bacteria, as well as fungal infections. In summary, the seed extracts of S. marianum and P. oleracea, which are among the available plant sources, can be used for the highly stable production of AgNPs as a reducing and capping agent. [ABSTRACT FROM AUTHOR]

The scientific society is exploiting the use of nanoparticles in nano-medicine and biomedical applications. In the field of biomaterial and bio-nanotechnology, silver nanoparticles (AgNPs) are playing an important role due to their potential physical, chemical, and biological properties ranging in activities from antibacterial, antiviral, antifungal, and anticancer treatment. Green synthesis technology is one of the most cost-effective, eco-friendly, and biologically safe methods. Green tea leaf extract can reduce silver to AgNPs and enhance antibacterial activity. In this work, we demonstrate the antibacterial activity effect employing green synthesis of AgNPs with green tea leaf extract. The UV–Vis and FTIR results showed, confirming the formation of AgNPs and the presence of chemical groups enhancing the antibacterial activity of AgNPs. The synthesized AgNPs with green tea leaf extract were crystalline with a quasi-spherical shape with a diameter from 30 to 150 nm. The antibacterial activity of the AgNPs in three different concentrations showed that the 120 mg/ml sample possesses higher antibacterial activity (significantly high killing ability) against E. coli than chemically produced AgNPs. These results confirm a more significant antibacterial effect of the biogenic AgNPs with low cytotoxicity than the AgNPs produced chemically. These findings can be used to treat chronic infections, diseases, and other biomedical applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have special plasmonic and antibacterial characteristics that make them efficient in a variety of commercial medical applications. According to recent research, chemically synthesized silver nanoparticles are harmful even in low concentrations. It was crucial to identify appropriate synthesis methods that may have low costs and be nontoxic to the environment. Zingiber officinale (ginger) extracts used to prepare silver nanoparticles were inexpensive and environmentally friendly, and the best physicochemical characteristics were analyzed. Silver nanoparticles were characterized by using UV-visible spectroscopy, Scanning electron microscopy (SEM), and X-ray diffraction (XRD). The surface Plasmon resonance peak at 425 nm was observed using UV-Visible spectroscopy. Scanning electron microscopy observed that the nanoparticles were spherical and ranged in size from 5 to 35 nm. The XRD pattern values of 2θ: 38.2o, 46.3o, and 64.58o are used to determine the planes (111), (200), and (220). The silver nanoparticle's existence was verified by the face-centered cubic (FCC). Silver nanoparticles were found to have antibacterial efficacy against gram-positive Staphylococcus and gram-negative bacteria such as Pseudomonas aeruginosa, Klebsiella Aerogenes, Salmonella, Staphylococcus and Escherichia coli. The antibacterial activity of silver nanoparticles was observed using the agar well diffusion (AWD) method at three different concentrations (100 μg/ml, 75 μg/ml, and 50 μg/ml). The zone of inhibition measured against the bacterial strains pseudomonas Aeruginosa, Klebsiella aerogenes, Escherichia coli, Salmonella and Staphylococcus which were (18.4±1.25 mm, 16.9±0.74 mm, 14.8±1.25 mm), (16.8±0.96 mm, 14.6±0.76 mm, 14.0±1.15 mm), (19.7±0.76 mm, 18.2±0.66 mm, 15.4±1.15 mm), (16.6±0.67 mm, 14.2±0.23 mm, 12.8±0.78 mm) and (12±0.68 mm, 10±0.20 mm, 08±0.15 mm). These nanoparticles' potent antibacterial properties may enable them to be employed as nanomedicines for a variety of gram-negative bacterial illness treatments. [ABSTRACT FROM AUTHOR]

Phytogenically synthesised nanoparticle (NP)-based drug delivery systems have promising potential in the field of biopharmaceuticals. From the point of view of biomedical applications, such systems offer the small size, high surface area, and possible synergistic effects of NPs with embedded biomolecules. This article describes the synthesis of silver nanoparticles (Ag-NPs) using extracts from the flowers and leaves of tansy (Tanacetum vulgare L.), which is known as a remedy for many health problems, including cancer. The reducing power of the extracts was confirmed by total phenolic and flavonoid content and antioxidant tests. The Ag-NPs were characterised by various analytical techniques including UV–vis spectroscopy, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), Fourier transform infrared (FT-IR) spectroscopy, and a dynamic light scattering (DLS) system. The obtained Ag-NPs showed higher cytotoxic activity than the initial extracts against both human cervical cancer cell lines HeLa (ATCC CCL-2) and human melanoma cell lines A375 and SK-MEL-3 by MTT assay. However, the high toxicity to Vero cell culture (ATCC CCL-81) and human fibroblast cell line WS-1 rules out the possibility of their use as anticancer agents. The plant-mediated Ag-NPs were mostly bactericidal against tested strains with MBC/MIC index ≤4. Antifungal bioactivity (C. albicans, C. glabrata, and C. parapsilosis) was not observed for aqueous extracts (MIC > 8000 mg L−1), but Ag-NPs synthesised using both the flowers and leaves of tansy were very potent against Candida spp., with MIC 15.6 and 7.8 µg mL−1, respectively. [ABSTRACT FROM AUTHOR]

Leather is often used to make comfortable shoes due to its soft and breathable nature. However, its innate ability to retain moisture, oxygen and nutrients renders it a suitable medium for the adsorption, growth, and survival of potentially pathogenic microorganisms. Consequently, the intimate contact between the foot skin and the leather lining surface in shoes, which are subject to prolonged periods of sweating, may result in the transmission of pathogenic microorganisms and cause discomfort for the wearer. To address such issues, we modified pig leather with silver nanoparticles (AgPBL) that were bio-synthesized from Piper betle L. leaf extract as an antimicrobial agent via the padding method. The evidence of AgPBL embedded into the leather matrix, leather surface morphology and element profile of AgPBL-modified leather samples (pLeAg) was investigated using colorimetry, SEM, EDX, AAS and FTIR analyses. The colorimetric data confirmed that the pLeAg samples changed to a more brown color with higher wet pickup and AgPBL concentration, owing to the higher quantity of AgPBL uptake onto the leather surfaces. The antibacterial and antifungal activities of the pLeAg samples were both qualitatively and quantitatively evaluated using AATCC TM90, AATCC TM30 and ISO 16187:2013 test methods, approving a good synergistic antimicrobial efficiency of the modified leather against Escherichia coli and Staphylococcus aureus bacteria, a yeast Candida albicans and a mold Aspergillus niger. Additionally, the antimicrobial treatments of pig leather did not negatively impact its physico-mechanical properties, including tear strength, abrasion resistance, flex resistance, water vapour permeability and absorption, water absorption and desorption. These findings affirmed that the AgPBL-modified leather met all the requirements of upper lining according to the standard ISO 20882:2007 for making hygienic shoes. [ABSTRACT FROM AUTHOR]

The investigation of using medicinal plants for the production and application of silver nanoparticles (AgNPs) has attracted growing research interest. In this study, AgNPs are synthesized from the stem barks of the Pyrus pashia medicinal plant using a biosynthetic strategy. The reaction conditions were optimized under ambient conditions, including concentration, temperature, time, and pH, and various techniques were employed, such as UV-visible, FTIR, XRD, FESEM, and TEM, to characterize the synthesized AgNPs. The AgNPs produced through this biosynthesis method were found to be spherical and polydispersed, with an average size of 23.92 ± 7.04 nm. The synthesized AgNPs demonstrated an enhanced DPPH free radical scavenging capacity compared to the aqueous extract, with IC50 values of 10.67 ± 0.05 µg/mL and 13.66 ± 0.35 µg/mL, respectively. In the agar well diffusion method, the synthesized AgNPs showed higher antibacterial activity than that of the extract against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Salmonella typhi (ATCC 14028), and Shigella sonnei (ATCC 25931). Based on these findings, the study suggests that green synthesized AgNPs from P. pashia could be used for biomedical applications. [ABSTRACT FROM AUTHOR]

The biogenic synthesis of silver nanoparticles (AgNPs) has attracted many researchers due to their physical, chemical, optical, and biological properties, embracing a range of activities such as antibacterial, antifungal, anti-inflammatory, and anticancer activities. The purpose of this work is to synthesize and characterize AgNPs using Argyreia nervosa (AN) plant leaf extract, as well as to test their antimicrobial applications. In this work, silver nitrate (AgNO3) at 0.1 mM concentration and stable AgNPs were synthesized and observed by monitoring the color change of the solution from light yellow to brown. The UV–Vis spectrum shows a peak at 445 nm, confirming the formation of AN-AgNPs and Fourier transform infrared (FTIR) results confirm the presence of chemical groups which act as reducing agents stabilizing the AN-AgNPs and antimicrobial capping agents enhancing antimicrobial properties of AN-AgNPs. The crystalline behavior of these AN-AgNPs is confirmed through X-ray powder diffraction (PXRD) peaks. The morphology of AN-AgNPs and their sizes were studied (sizes range from 10 to 40 nm) using scanning electron microscopy (SEM). The disk diffusion assay shows the antimicrobial activity over Escherichia coli pathogenic microorganisms of clinical interest. The obtained results confirm a more significant antimicrobial effect of the biogenic AN-AgNPs maintaining low cytotoxicity. This work presents a potential way to produce non-toxic biogenic AgNPs with enhanced antibacterial activity, which can meet the increasing global demand for biogenic AgNPs as an alternative to antibiotics. [ABSTRACT FROM AUTHOR]

The current work aimed to find substitutes for antibiotics because of the side effects of antibacterial agents and the expansion of bacterial resistance to these agents. The scope of this study was to evaluate the antibacterial activity of gold and silver nanoparticles (AuNPs and AgNPs) against selected animal pathogens (Staphylococcus aureus, Klebsiella pneumonia, Streptococcus pneumoniae, Escherichia coli, Bacillus abortus and Mycobacterium bovis). The synthesized nanoparticles were distinguished by scanning electron microscopy (SEM) analysis and tested for antibacterial activity with the broth microdilution method, well diffusion assay, and minimum bactericidal concentration procedure. Results showed that both AuNPs and AgNPs displayed good antibacterial activity against all tested bacteria. The strongest antibacterial action of AgNPS (18 mm) was against E. coli. AuNPs displayed good antibacterial activity against S. aureus and B. bovis with a suppression area of 14 mm. Therefore, it is suggested that AgNPs and AuNPs could be effectively used against animal pathogens and may contribute to reducing antibiotic resistance. However, there is a need for further research on the in vivo toxicity and mechanisms of action of AuNPs and AgNPs. [ABSTRACT FROM AUTHOR]

Green synthesis of metal nanoparticles (NPs) from plant extracts has attracted significant interest in modern medicine. therefore, this study prepared an aqueous extract of Sophora flavescens roots, which are used in folk medicine to treat several diseases, including bacterial infections. in addition, silver NPs (AgNPs) were synthesized from root extract using the green synthesis method. the NPs were diagnosed using modern methods. Additionally, the antibacterial activity of the root aqueous extract and AgNPs aqueous preparation (at concentrations of 7% and 9%, respectively) was examined against selected isolates of multidrug-resistant Pseudomonas aeruginosa and Staphylococcus aureus. the results indicated that both the plant extract and NP preparations inhibited pathogenic bacterial isolates. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) biosynthesized using aqueous medical plant extracts as reducing and capping agents show multiple applicability for bacterial problems. The aim of this study was to expand the boundaries on AgNPs using a novel, low-toxicity, and cost-effective alternative and green approach to the biosynthesis of metallic NPs using Calendula officinalis (Calendula) and Hyssopus officinalis (Hyssopus) aqueous extracts. The formation of AgNPs was confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques. The effectiveness of biosynthesized AgNPs in quenching free radicals and inhibiting the growth of Gram-positive and Gram-negative microorganisms was supported by in vitro antioxidant activity assay methods and using the Kirby–Bauer disk diffusion susceptibility test, respectively. The elucidated antimicrobial and antioxidative activities of medical plant extracts were compared with data from the engineered biosynthetic AgNPs. The antimicrobial effect of engineered AgNPs against selected test cultures was found to be substantially stronger than for plant extracts used for their synthesis. The analysis of AgNPs by TEM revealed the presence of spherical-shaped nano-objects. The size distribution of AgNPs was found to be plant-type-dependent. The smaller AgNPs were obtained with Hyssopus extract (with a size range of 16.8 ± 5.8 nm compared to 35.7 ± 4.8 nm from Calendula AgNPs). The AgNPs' presumably inherited biological functions of Hyssopus and Calendula medical plants can provide a platform to combat pathogenic bacteria in the era of multi-drug resistance. [ABSTRACT FROM AUTHOR]

Nanotherapeutic agents play a crucial role in medicine and the bio-nanotechnology field. Because of its cost-effectiveness, plant-based nanoparticle production has sparked a lot of attention, sustainable way, eco-friendly nature, and a plethora of applications. In the present study, the antioxidant and antimicrobial potential of silver nanoparticles (AgNPs) of aqueous extract of Nigella Sativa seeds have been investigated. AgNPs synthesized using N. Sativa extract, characterized by UV-Vis spectroscopy, FTIR, X-ray diffraction (XRD), SEM, and energy dispersive spectroscopy (EDX) techniques showed a peak at 430 nm, with size ranging between 12.97 and 16.37 nm with a spherical shape. Three assays were used to test the antioxidant activity of biosynthesized silver nanoparticles: DPPH, FRAP, and TAC radical scavenging assays, all of which showed strong antioxidant capacity. The disk diffusion method was used for determining the antimicrobial activity of AgNPs. Evaluation of the antimicrobial potential of biosynthesized AgNPs registered the highest inhibitory activity against S. aureus (17.38 mm) followed by E. coli (16.45 mm), B. subtilis (15.5 mm), P. aeruginosa (14.6 mm), and S. Typhimurium (14.35 mm). It was noted that the increased extract concentration in biosynthesized AgNPs leads to a higher zone of inhibition. These results indicated that AgNPs have an effective and strong antimicrobial activity that provides a marvelous source for the development of a new antibacterial drug that can be used for solving the problem of microbial resistance. [ABSTRACT FROM AUTHOR]

Nanomedicine is a potential provider of novel therapeutic and diagnostic routes of treatment. Considering the development of multidrug resistance in pathogenic bacteria and the commonness of cancer, novel approaches are being sought for the safe and efficient synthesis of new nanoparticles, which have multifaceted applications in medicine. Unfortunately, the chemical synthesis of nanoparticles raises justified environmental concerns. A significant problem in their widespread use is also the toxicity of compounds that maintain nanoparticle stability, which significantly limits their clinical use. An opportunity for their more extensive application is the utilization of plants, fungi, and bacteria for nanoparticle biosynthesis. Extracts from natural sources can reduce metal ions in nanoparticles and stabilize them with non-toxic extract components. [ABSTRACT FROM AUTHOR]

Bacterial resistance to antibiotics is on the rise and hinders the fight against bacterial infections, which are expected to cause millions of deaths by 2050. New antibiotics are difficult to find, so alternatives are needed. One could be metal-based drugs, such as silver nanoparticles (AgNPs). In general, chemical methods for AgNPs' production are potentially toxic, and the physical ones expensive, while green approaches are not. In this paper, we present the green synthesis of AgNPs using two Pseudomonas alloputida B003 UAM culture broths, sampled from their exponential and stationary growth phases. AgNPs were physicochemically characterized by transmission electron microscopy (TEM), total reflection X-ray fluorescence (TXRF), infrared spectroscopy (FTIR), dynamic light scattering (DLS), and X-ray diffraction (XRD), showing differential characteristics depending on the synthesis method used. Antibacterial activity was tested in three assays, and we compared the growth and biofilm-formation inhibition of six test bacteria: Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. We also monitored nanoparticles' synergic behavior through the growth inhibition of E. coli and S. aureus by three classical antibiotics: ampicillin, nalidixic acid, and streptomycin. The results indicate that very good AgNP activity was obtained with particularly low MICs for the three tested strains of P. aeruginosa. A good synergistic effect on streptomycin activity was observed for all the nanoparticles. For ampicillin, a synergic effect was detected only against S. aureus. ROS production was found to be related to the AgNPs' antibacterial activity. [ABSTRACT FROM AUTHOR]

The present study investigated the biomedical potential of eco-friendly Citrullus colocynthis-mediated silver nanoparticles (Cc-AgNPs). The antibacterial efficacy of Cc-AgNPs was evaluated against two multidrug-resistant pathogenic bacterial strains, Escherichia coli and Pseudomonas aeruginosa. The antiproliferative and antilipidemic performance of the prepared particles was determined against the MCF7 cell line, a breast cancer cell line. The in vitro antibacterial assay revealed that Cc-AgNPs induced dose-dependent bactericidal activity, as a considerable increase in the zone of inhibition (ZOI) was noted at higher concentrations. Reduced proliferation, migration, spheroid size, and colony formation exhibited the substantial antiproliferative potential of Cc-AgNPs against MCF7 cells. Significant alterations in the expression of cell surface markers, apoptosis, and cell proliferation genes further confirmed the antiproliferative impact of Cc-AgNPs. Moreover, Cc-AgNPs exhibited antilipidemic activity by reducing cellular cholesterol and triglyceride levels and regulating key genes involved in lipogenesis. In conclusion, these results propose that Cc-AgNPs can be employed as a potent tool for future antibacterial and anticancer applications [ABSTRACT FROM AUTHOR]

[Display omitted] • We observed the presence of various phytochemicals and antibacterial activity against MDR bacteria and anticancer. • The presence of various phytochemicals has been observed qualitatively and quantitatively. • IC 50 analyses reveal that at a concentration of 1000 µg plant ethanolic extract was active against AGS cell lines. • The prepared AgNPs were highly effective against human gastric cancer cell lines. Bacterial resistance to antibacterial drugs has become a major health problem globally, thus natural products can be used as additional drugs to solve this problem. Hence, the present study is performed to examine bioactive chemicals, the antibacterial and anticancer activity of various solvent extracts and the antibacterial potential of greenly synthesized silver nanoparticles (AgNPs) of O. japonicum. The analysis of the data shows that different phytochemicals like phenols, coumarins, carotenoids, phlobatanins, terpenoids, saponins, glycosides, tannins, alkaloids, and flavonoids were present in O. japonicum. Higher quantities of phenols, sugar, and ascorbic acid were observed, while lower quantities of flavonoids, anthocyanins and proline were examined during spectrophotometry. Greenly synthesized nanoparticles show higher antibacterial activity against all selected bacterial strains. AgNPs show UV–vis absorbance peak at 428 nm, which indicates the synthesis of AgNPs. Face centered cubic structure of AgNPs was represented by three major sharp XRD peaks. Various peaks were observed at 3358, 2910, 1670, 1585, 1278, 1117, 1040, 803, 680 cm−1 during FTIR analysis, pointing out the stretching vibrations of C-H, O-H, C O, C-O, C O, C-O, aromatic C-H and C-X bonds. According to SEM analysis, the synthesized AgNPs have an oval shape and the average size of AgNPs was calculated at 62 nm. The EDS graph also shows the presence of a single sharp peak indicating the presence of reduced AgNPs. All the organic solvent extracts of O. japonicum show prominent activity against S. aureus (N-hexane = 20.33 mm, chloroform = 16.66 mm, ethyl acetate = 15 mm, methyl alcohol = 14 mm) and K. pneumonia (N-hexane = 16.66 mm, chloroform = 14.33 mm), while lower inhibitory zones were observed against E. coli and P. aeruginosa. Cell proliferation assay, IC 50 analyses reveal that at a concentration of 1000 µg plant ethanolic extract was highly active against SGC and AGS cell lines. We concluded based on present results that O. japonicum has plenty of vital chemicals and could be used as a complement to conventionally be used antibiotics. [ABSTRACT FROM AUTHOR]

[Display omitted] • First time report on green-synthesis of AgNPs using aqueous extract of S. sisymbriifolium fruits. • The characterization studies were employed to elucidate the physical properties of AgNPs. • The synthesized AgNPs possessed profuse antioxidant and antibacterial activity in comparison to crude extract. • The green-synthesized AgNPs exhibited strong degradation of methylene blue under solar and UV-irradiations. The present research work focused on biological synthesis of silver nanoparticles using Solanum sisymbriifolium aqueous fruit extract (AgNPs@SsFE) and determining their pharmaceutical and environmental aspects for the first time. The phytochemicals extracted from S. sisymbriifolium fruit extract (SsFE) contributed in reducing the average particle size of green synthesized AgNPs@SsFE to 23.17 nm and served as capping agents. Further, when AgNPs@SsFE were characterized using PSA, ZP, FE–SEM, Elemental mapping, EDX, HR–TEM, SAED, FTIR and XRD, exhibited the high colloidal stability, spherical shape and crystalline nature of the nanoparticles. Moreover, the synthesized AgNPs@SsFE exhibited enhanced antioxidant activity in comparison to SsFE when assayed via DPPH, FRAP, •NO and H 2 O 2 scavenging methods. The Agar well–diffusion analysis unveiled AgNPs@SsFE to possess greater antibacterial activity against highly pathogenic gram–negative strains than gram–positive strains. Besides, the synthesized AgNPs@SsFE established itself to be a strong photocatalyst by degrading the methylene blue cationic dye under Solar and UV irradiations. These features of synthesized AgNPs@SsFE are found promising to convince the efficacy of SsFE in synthesizing the nanoparticles which can be useful in modern medicine and clinical applications. [ABSTRACT FROM AUTHOR]

Background: These days, silver nanoparticles (Ag NPs) have been given considerable attention and applied in medical technology due to their great antimicrobial and antioxidant features. In the present study, we aimed to synthesize Ag NPs through the reduction of silver nitrate in the presence of Vitex agnus castus L fruit extract. Methods: After collecting fruits, their extract was prepared and added to Ag NO3 to produce Ag NPs. The effect of different parameters like AgNO3 concentration (0.5, 1, 3, and 5 mM), sunlight exposure, and sunlight irradiation time (10, 20, 30, and 40 min) was investigated in the synthesis of Ag NPs. The features of Ag NPs were characterized using UV-visible spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD) analysis, and dynamic light scattering analysis. Moreover, antimicrobial function of Ag NPs was evaluated using Escherichia coli and Bacillus cereus bacteria species and minimal inhibitory concentration (MIC) of Ag NPs against these two pathogens was measured. Results: The results showed that the synthesized nanoparticles had a spherical shape and the range size of 30-60 nm. For the first time, the antimicrobial activity of synthesized Ag NPs of Vitex agnus castus L fruit extract was shown. Conclusions: It can be stated that the biosynthesis of Ag NPs using fruit extract of this plant is an environmentally friendly, economic and harmless method without any use of poisonous substances and no side effects. These Ag NPs can be considered as suitable antibacterial agents and replacements for antibiotics. [ABSTRACT FROM AUTHOR]

The development of green, low cost and sustainable synthetic routes to produce metal nanoparticles is of outmost importance, as these materials fulfill large scale applications in a number of different areas. Herein, snail slime extracted from Helix Aspersa snails was successfully employed both as bio-reducing agent of silver nitrate and as bio-stabilizer of the obtained nanoparticles. Several trials were carried out by varying temperature, the volume of snail slime and the silver nitrate concentration to find the best biogenic pathway to produce silver nanoparticles. The best results were obtained when the synthesis was performed at room temperature and neutral pH. UV–Visible Spectroscopy, SEM-TEM and FTIR were used for a detailed characterization of the nanoparticles. The obtained nanoparticles are spherical, with mean diameters measured from TEM images ranging from 15 to 30 nm and stable over time. The role of proteins and glycoproteins in the biogenic production of silver nanoparticles was elucidated. Infrared spectra clearly showed the presence of proteins all around the silver core. The macromolecular shell is also responsible of the effectiveness of the synthesized AgNPs to inhibit Gram positive and Gram negative bacterial growth. [ABSTRACT FROM AUTHOR]

In this study, the antibacterial and antifungal properties of silver nanoparticles synthesized with the aqueous plant extract of Acer oblongifolium leaves were defined using a simplistic, environmentally friendly, reliable, and cost-effective method. The aqueous plant extract of Acer oblongifolium, which served as a capping and reducing agent, was used to biosynthesize silver nanoparticles. UV visible spectroscopy, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and scanning electron microscopy were used to analyze the biosynthesized Acer oblongifolium silver nanoparticles (AgNPs). Gram-positive bacteria (Bacillus paramycoides and Bacillus cereus) and Gram-negative bacteria (E. coli) were used to test the AgNPs' antibacterial activity. The presence of different functional groups was determined by FTIR. The AgNPs were rod-like in shape. The nanoparticles were more toxic against Escherichiacoli than both Bacillus cereus and Bacillus paramycoides. The AgNPs had IC50 values of 6.22 and 9.43 and mg/mL on HeLa and MCF-7, respectively, proving their comparatively strong potency against MCF-7. This confirmed that silver nanoparticles had strong antibacterial activity and antiproliferative ability against MCF-7 and HeLa cell lines. The mathematical modeling revealed that the pure nanoparticle had a high heat-absorbing capacity compared to the mixed nanoparticle. This research demonstrated that the biosynthesized Acer oblongifolium AgNPs could be used as an antioxidant, antibacterial, and anticancer agent in the future. [ABSTRACT FROM AUTHOR]

The chemical content of plant excerpts can be efficiently employed to reduce the metal ions to nanoparticles in the one-pot green production method. Here, green production of silver nanoparticles (AC-AgNPs) is performed by means of Allium cepa var. Aggregatum (shallot) extract as a stabilizer and reducer. The shape, size, and morphology of resultant AC-AgNPs are examined by optical spectroscopy analysis such as UV for nucleation and coalescence processes of the AC-AgNPs. Through FTIR functional group is determined and through DLS size is defined, it was confirmed that metallic AgNPs were successfully synthesized through the green synthesis route, and these results agreed well with the results obtained in the XRD pattern along with TEM spectroscopy, where the TEM images confirm the formation of sphere-like nanostructures along with SAED analysis. The chemical characterization is performed with XPS; the obtained molecular species in the materials are determined from the energy profile. Antioxidant activity of AC-AgNPs versus DPPH substrate is carried out. Antibacterial activity is well established against Gram-negative and Gram-positive organisms. Cell viability is accomplished, followed by an MTT assay, and a cytotoxicity assay of AC-AgNPs on MCF—7 cell lines is also carried out. Highlights: (1). This study highlights the eco-friendly synthesis of silver nanoparticles from Allium cepa var. Aggregatum Natural Extract. (2). The synthesized AC-AgNPs were characterized by UV-VIS, FT-IR, XRD, TEM, and XPS. (3). The synthesized nanoparticles were well dispersed in nature and the size range of 35 ± 8 nm. (4). The anti-candidal activity of biosynthesized silver nanoparticles was evaluated against the following Gram-Negative organisms: Escherichia coli (E. coli), and the following Gram-positive organisms: Staphylococcus aureus strains. The biosynthesized AC-AgNPs showed enhanced antiseptic features anti both Gram-positive and negative organisms. (5). Besides, the in vitro cytotoxic outcomes of AC-AgNPs were assessed versus MCF-7 cancerous cells, and the reduction in the feasibility of cancer cells was established via MTT assay, which suggests potential biomedical applications. [ABSTRACT FROM AUTHOR]

• Green synthesis of silver nanoparticles was provided using Haloxylon persicum. • Parameters affecting the reduction of silver nanoparticles were investigated. • Photocatalytic, and antibacterial activities of nanoparticles were confirmed. • Silver nanoparticles were non-toxic to human cells at bactericidal concentrations. The biological synthesis of metal nanoparticles is considered a fast, environmentally friendly and cost-effective technology. This study investigated the synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Haloxylon persicum leaf as a rangeland plant. The formation of AgNPs was examined by UV–Vis spectroscopy, X-ray diffraction, Fourier transform infrared (FTIR), energy-dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). The color change of the sample from yellow to brown and the absorption peak of about 430 nm showed the synthesis of AgNPs. X-ray diffraction analysis demonstrated AgNP crystal planes with a face-centred cubic (FCC) structure at (111), (200), (220), and (311). FTIR analysis revealed that nanoparticles are coated with plant compounds and phenolic compounds; tannins and flavonoids in the extract act as reducing and stabilizing agents. EDX analysis showed a distinct peak at 3.0 kV, which indicated the successful synthesis and high purity of the AgNPs. Electron microscopy estimated the average size of synthesized AgNPs to be 10 nm. Analysis of the results of the total antioxidant capacity and free radical scavenging activity showed that the synthesized AgNPs have higher antioxidant activity than the plant extract. Also, the AgNPs indicated antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The results of this study provide the field of further development of antibacterial and antioxidant drugs using cost-effective and environmentally friendly methods. [Display omitted] [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles provides an advancement over chemical and physical methods given its cost-effectively, environment-friendly, facile, and suitability for large-scale industrial production. Due to their characteristics, silver nanoparticles are exploited in various fields such as developing electronic devices, biosensing platforms, catalysts, wastewater purification, biomedicine, antifungal, and antibacterial agent. In this study, silver nanoparticles (Ag-NPs) were synthesized using leaves extract of Biarum chaduchrum at ambient temperature, and characterized through transmission electron microscopy, particle size analyzer, and fourier transform infrared spectroscopy. The average size of synthesized Ag-NPs was estimated at 100 nm with a spherical shape. In addition, the antibacterial activity of nanoparticles against Staphylococcusaureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa was tested by minimum inhibitory concentration analysis. According to the results and observations, this procedure can be applied for large-scale synthesis of Ag-NPs and other notable metal nanoparticles with medicinal and industrial use. [ABSTRACT FROM AUTHOR]

In this study, novel hydrogels based on polyurethane/polyethylene glycol (PU/PEG) and their silver nanocomposites (PU/PEG/Ag x, x = 100, 200, 400, and 800) were developed using click chemistry and a green method. Mechanical analysis showed that introducing of silver nanoparticles (AgNPs) into hydrogels and increasing the content increased their mechanical properties dramatically. Tensile strength and elongation at break increased from 0.2 MPa and 105% for PU/PEG to 2.5 MPa and 210% for PU/PEG/Ag 800. Similarly, the compressive strength increased from 5 to 55 MPa. Investigation of the SEM images showed that the AgNPs were homogeneously dispersed throughout the hydrogel network, and through the incorporation of silver nanoparticles in hydrogels, the pore size of hydrogels decreased. Therefore, the swelling degree of hydrogels decreased by increasing the content of AgNPs. FTIR spectroscopy and X‐ray photoelectron spectroscopy (XPS) demonstrated that the interaction of network heteroatoms with AgNPs was responsible for stabilizing silver nanoparticles. The antibacterial properties of nanocomposites were evaluated against Pseudomonas aeruginosa and Staphylococcus aureus bacteria. These nanocomposites showed significant activities against S. aureus bacteria. In addition, the cell viability test showed that these nanocomposites had good biocompatibility (84% cells viable). Therefore, they could be favorable candidates for wound dressing applications. [ABSTRACT FROM AUTHOR]

Various synthesis methods are being developed in order to increase the number of scientific fields where nanoparticles can be used. Recently, the biosynthesis methods have eliminated the limitations of the traditional synthesis methods such as physical and chemical ones. They have been also developed as an alternative synthesis method. With green synthesis called herbal nanofactories, primary and secondary metabolites in plants enable the reduction and capping of nanoparticles. The functional groups of alkaloids, phenolics, terpenoids, ketones, polysaccharides, proteins, vitamins, and amino acids in plants react with silver metals in ionic form and reduce "+" valued metals to "0" valued nanostructures. At the same time, functional groups of secondary metabolites form bonds with "0" valued silver nanometals and cover the surface of silver nanometals; thus, stabilization is achieved. Synthesis by biological methods provides high efficiency and rapid synthesis and the production cost of silver nanoparticle decreases. Moreover, biosynthesis is an environment-friendly technique as it takes place inside a living being. With the latest technology, silver nanoparticles stand out in the fields of biosensor and photoimaging. In this review, in which areas silver nanoparticles are used and their biosynthesis, stabilization, characterization, antibacterial mechanism, and use as a biosensor will be discussed. [ABSTRACT FROM AUTHOR]

Herein, we report the green synthesis of silver nanoparticles using the aqueous extract of root of Angilica glauca Edgew. UV-vis and FT-IR spectroscopies, X-ray diffraction analysis and scanning electron microscopy technique were employed to structurally and morphologically characterize the green synthesized silver nanoparticles. The nanoparticles were found to be spherical in shape with an average size of ∼21 nm. The extract was found to be rich in phenolic and flavonoid contents. Both the extract and the extract-loaded silver nanoparticles inhibited the growth of both Pseudomonas aeruginosa (inhibition zone 13.0 ± 1.6 and 4.0 ± 0.9 mm, respectively) and Escherichia coli (inhibition zone 12.0 ± 1.1 and 3.0 ± 0.6 mm, respectively) at 9.0 µg/mL. The antioxidant potential of the extract (IC50 = 30.79 ± 3.2 µg/mL) was determined via DPPH radical scavenging assay. These nanoparticles are concluded to possess antibacterial potentials. [ABSTRACT FROM AUTHOR]

The present work investigates the synthesis of silver nanoparticles (AgNPs) by a biological method using L.Rosa flower extract and silver nitrate as precursors. Optimum conditions of synthesis were studies, such as pH, temperature, concentration of extract, concentration of silver nitrate, and stability with time. Characterization of AgNPs was carried out using UV-visible Spectroscopy, Scanning Electron Microscopy, X-Ray Diffraction, Fourier Transform Infrared and Transmission Electron Microscopy. The biosynthesized AgNPs exhibited inhibitory effects on creatine kinase activity in the sera of patients with myocardial infarction, compared with control subjects. Thermodynamic and kinetic studies of creatine kinase were performed. Further studies on other biological activities were performed to exploit AgNPs full potential. In conclusions, the present study utilize a simple, cheap and environmentally green method to synthesize silver nanoparticles. This single step procedure is more suitable for large scale production as it is rapid and eliminates the elaborate processes employed in the other bio-based protocols (e.g. by using fungi and bacteria). [ABSTRACT FROM AUTHOR]

Delonix regia has bioactive phytochemicals present in leaves, seeds, roots, and flowers. Considering that these compounds are common in extracts used for silver nanoparticles (AgNPs) biosynthesis, this study investigated the potential of D. regia seeds aqueous extract (DRE) in different concentrations to produce AgNPs (DRE-AgNPs). DRE composition was investigated by qualitative assays, and physico-chemical/structural characterization of AgNPs was performed by UV–Visible spectroscopy, dynamic light scattering (DLS), Zeta potential, and atomic force microscopy (AFM). Antibacterial effect of DRE-AgNPs was evaluated against Escherichia coli and Staphylococcus aureus. DRE presented mainly tannins and saponins. Additionally, the absorbance of each DRE-AgNPs was positively correlated to DRE concentration. At higher DRE concentrations, AgNPs were larger, regarding Z average; tended to monodispersity; and presented more negative Zeta potentials. Hydrodynamic diameters of DRE-AgNPs were measured by number distribution and only AgNPs synthesized with DRE 2 mg ml−1 (DRE-AgNPs 2) presented a single population of particles. Thus, DRE-AgNP 2 was analyzed by AFM and exhibited a spherical shape and an average height of 18.39 ± 1.59 nm. Most of DRE-AgNPs presented antibacterial effects against E. coli and S. aureus at 128 or 256 µmol l−1. In conclusion, different DRE concentrations modulated physico-chemical characteristics of AgNPs with antibacterial activity. [ABSTRACT FROM AUTHOR]

The aim of the present work was to synthesize carrageenan coated silver nanoparticles (CA–AgNPs) using carrageenan as reducing and stabilizing agent. For this purpose, 10 mL of 0.35% (w/v) carrageenan solution was mixed with 10 mL AgNO3 solution at different concentrations (1, 5 and 10 mM), and the resulting mixture was stirred at 100 °C at high speed for 2 h. The formation of CA–AgNPs was proven with the surface plasmon peaks observed at approximately 420 nm. The sizes and zeta potentials of CA–AgNPs were determined by Zeta-Sizer. Negative zeta potentials of CA–AgNPs indicated that the obtained AgNPs were stable. With scanning electron microscope (SEM) and transmission electron microscope analysis, it was seen that CA–AgNPs have spherical structure. According to the energy dispersion spectrometer analysis based on SEM images, it was observed that the samples were elementally composed of carbon, oxygen, sulfur, potassium and silver. The chemical structures of CA–AgNPs were determined by Fourier transform infrared spectroscopy, and it was proved that the carbonyl and OH groups of carrageenan were involved in formation and stabilizing of AgNPs, respectively. According to thermal gravimetric analysis, it has been observed that CA–AgNPs were thermally more stable than pure carrageenan. Antibacterial activity of CA–AgNPs against gram-positive and gram-negative bacteria was investigated with agar well diffusion and liquid test. It has been observed that CA–AgNPs synthesized with 1 mM AgNO3 did not have an antibacterial activity on Escherichia coli and Staphylococcus aureus. Inhibition zones of varying diameters were observed in the 5 mM and 10 mM S-AgNPs groups. The synthesized CA–AgNPs (5 and 10 mM) have the capacity to be used in wound dressing materials or topical agents applied to burns and wounds due to their antibacterial effects and stability. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (AgNPs) was carried out using the aqueous leaf extract of rare medicinal plant Decaschistia crotonifolia (Dc). The spectral characterization of the biosynthesized Dc-AgNPs was carried out by using different spectral methods viz., ultraviolet visible spectroscopy (UV-Vis) showed that Dc-AgNPs have surface plasmon resonance (SPR) peak at 437 nm. Fourier transform infrared spectroscopy (FTIR) analysis revealed the role of various functional groups responsible for the synthesis and the stabilization of Dc-AgNPs. In Transmission electron microscopy (TEM) studies, the Dc-AgNP average size is detected as 13.6 nm and all the nanoparticles are in the range of 12–18 nm with spherical shape and poly-dispersed nature. The stability of Dc-AgNPs was due to its high negative zeta potential value −26.0 mV. The X-ray diffraction (XRD) studies confirmed the crystalline nature of Dc-AgNPs. The Dc-AgNPs proved to have effective antimicrobial activity against Gram-positive and Gram-negative bacterial stains, also revealed excellent antioxidant and catalytic activity. [ABSTRACT FROM AUTHOR]

Cost-effective, eco-friendly green synthesis of silver nanoparticles was prepared using Psidium guajava plant leaf extract. In this study the reducing potential of Psidium guajava leaf extract was investigated for the synthesis of silver nanoparticles without any external addition of reducing agents. The brown color formation was evident for the synthesis of silver nanoparticles. The synthesized silver nanoparticles were characterized by UV–Visible spectroscopy, Fourier transform-infrared spectroscopy (FTIR), particle size analyzer, X-ray diffraction (XRD) and scanning electron microscope (SEM). UV–Vis spectroscopy explained that the main peak was formed at around 419 nm, which corresponds to surface plasmon resonance of silver nanoparticles. FTIR spectroscopy elucidated the involvement of various functional groups during the synthesis of silver nanoparticles. The particle size analysis demonstrated the sizes of nanoparticles are 62 nm. The morphology of silver nanoparticles was analyzed using scanning electron microscope. Antibacterial assay of silver nanoparticles showed potent antibacterial properties. [ABSTRACT FROM AUTHOR]

The plant extracts were applied for synthesis of Ag-nanoparticles and expected such biological processes benefit from advantages like eco-friendly, cost-effective, and safe for human use. Accordingly, polyphenol compounds and antioxidant properties of this understudy plant extract was initially qualified and quantified by GC-Mass and subsequently its ability for silver nanoparticle (AgNP) biosynthesis was examined. Consequently, under study (ethanol) extract was exposed to various content of AgNO3 solution over 0, 2.5, 5, 7.5, 10 and 15 mM for 24, 48, 72 and 96 h to search best operational conditions for AgNPs production, while sampling were done every 24 h monitoring initial absorption with UV–Vis spectroscopy. The peak with center at 460 nm emerged from surface plasmon resonance of AgNPs which is good indication of successful formation of AgNPs. The nanoparticles were characterized by DLS, SEM, TEM, XRD, and FTIR. Which reveal its spherical, shape and average diameter of 32 nm. Antioxidant activity tests showed that the half-maximal inhibitory concentration (IC50) in the C. tuberculata extract was 4.722 mg/ml. Antimicrobial activity of the AgNPs was tested by measurement of inhibition zone around discs modified with AgNPs in cultures of S. aureus, B. cereus, P. aeruginosa and E. coli. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is currently a global human health concern and insists on the importance of the production of new, alternative and most effective antibiotics. Nano-sized trace metals such as silver nanoparticles (AgNPs) is a potential material with antibacterial properties and hence the synthesis of this material is of considerable interest to the scientific community mainly for antimicrobial applications. In this work, we have successfully green synthesized the AgNPs using Cocos nucifera leaf aqueous extract as the natural reducing and stabilizing agent, and aqueous silver nitrate (AgNO3) solution as a precursor by a newly developed technique. The material was characterized by ultraviolet–visible (UV–Vis) spectrophotometry, X-ray diffractometry (XRD), Fourier transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM) analyses; and subsequently, evaluated their potential candidacy as antibacterial agents against some common human pathogens by the standard disc diffusion method. The synthesized AgNPs were identified by XRD analysis as a cubic crystal system with an average crystallite size of 14.2 nm. The aqueous colloidal suspension of AgNPs shows a UV–Vis absorption maxima of 380 nm indicating its formation. FT-IR analysis identified the C–N, –OH and N–H as the major and probable functional groups in the leaf extract responsible for the production of stable AgNPs. The results of antibacterial studies of the material showed the considerable zones of inhibition against both Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, and Citrobacter freundii) bacteria ranging from 10 to 20 mm with less inhibition for the former than the latter. The maximum (20 mm) and minimum (10 mm) inhibition zone was shown by C. freundii and Bacillus subtilis, respectively and P. aeruginosa shows the second-highest zone of inhibition (19 mm). The antibacterial performance of the material implies that the C. nucifera leaf extract mediated green synthesized AgNPs can be regarded as a potential candidate for antimicrobial application appreciably. [ABSTRACT FROM AUTHOR]

In this research, silver nanoparticles (AgNPs) are prepared by green synthesis method at ambient temperature using Eryngium caucasicum Trautv aqueous extract as reducing and natural capping agents. The AgNPs were defined using ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). XRD analysis confirmed the crystalline structure of the synthesized nanoparticles. UV–Vis spectra showed a surface resonance peak at 480 nm indicating the formation of AgNPs. The AgNPs average particle size was approximately 17.5 nm. FT-IR analysis was performed to identify the biomolecules responsible for bio reduction of silver ions. Synthesized AgNPs inhibitory activity was also examined toward pathogenic bacteria such as Staphylococcus aureus and Escherichia coli. The outcomes revealed that the synthesized AgNPs demonstrated modest inhibitory activities, displaying its antibacterial rate toward pathogenic diseases. [ABSTRACT FROM AUTHOR]

The biological synthesis of metal nanoparticles using plant extracts with defined size and morphology is a simple, nontoxic and environmentally friendly method. The present study focused on the synthesis of silver nanoparticles (Ag NPs) by Artemisia annua L. extract as reducing and stabilising agent. The Ag NPs function, as antibacterial agents, is with that they are further used in human therapy. The effects of pH and temperature on the synthesis of NPs were characterized by UV-absorption spectroscopy and shown by surface plasmon resonance (SPR) band at 410 nm. NPs' size and morphology were measured by transmission electron microscopy (TEM) and dynamic light scattering (DLS). TEM images showed that Ag NPs were in a nano-sized range (20–90 nm) and had spherical shape. Our findings demonstrated that lower concentration (100 µg mL−1) of the biogenic Ag NPs exhibited antibacterial activity against Gram-negative Escherichia coli BW 25113 and Gram-positive Enterococcus hirae ATCC 9790. [ABSTRACT FROM AUTHOR]