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There is a strong interest in using green resources for synthesizing nanoparticles (NPs) of industrial and biomedical utility in a way to maintain desired material properties throughout use while not inducing any harmful effects. The use of various plant extracts as reducing, capping, or stabilizing agents is widely attempted in green nanotechnology. However, very little has been explored about incorporating plant extract blends into green NP synthesis routes. Here, we used the combination of tea and olive leaf extracts for the synthesis of silver NPs and evaluated the advantages it provided over both chemical and single-plant-mediated synthesis routes. Four different reducing agents (tannic acid, black tea leaves extract, olive leaves extract and their blend) were used to synthesize silver NPs (Ag NP) from silver nitrate (AgNO 3). The synthesized Ag NP was characterized by scanning electron microscopy (SEM), dynamic light scattering (DLS), and ultraviolet-visible (US-Vis) spectroscopy. The antimicrobial properties of Ag NP were assessed against Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus) using the colony-forming unit (CFU) assay and the minimum inhibitory concentration (MIC) assay. The cytotoxic potential of Ag NP on human colorectal adenocarcinoma (Caco-2) cells was assessed by the WST-1 assay. Results showed that Ag NP synthesized using plant extract mixtures had a primary particle size of 40 nm and were very effective antibacterial agents, with the MIC values ranging from 5 μ g/mL to 10 μ g/mL. While the particle size obtained in chemical synthesis was slightly lower, the resultant Ag NP did not serve as an effective antibacterial agents at low doses. Further understanding of how best to integrate extracts of different plants into green NP synthesis routes will enable wider and safer biomedical applications. The mixture of olive and black tea leaf extracts was used to produce silver nanoparticles. Their antibacterial performance and cytotoxic potential were compared to those synthesized through chemical or single-plant-mediated routes. We demonstrated how alterations in fabrication methods would change nanoparticle properties that are critical in determining their functionality and biomedical applications. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were biosynthesized from a crude leaf extract of Rhizophora mucronata. The initial phytochemical analysis of the sample revealed the presence of tannins, steroids, terpenoids, saponins and flavonoids which contribute to the reduction and stabilization of silver ions during the synthesis process. Characterization techniques, including FTIR, UV–Vis spectroscopy, SEM and EDS, confirmed the successful synthesis of AgNPs with distinctive properties. The UV–Vis spectra exhibited an absorption peak around 420 nm, characteristic of AgNPs. SEM images revealed the crystal nature of the nanoparticles, indicating structural stability. The agar well-diffusion method was employed to determine the zone of inhibition against different pathogens. The leaf extract demonstrated the highest antibacterial potential, with substantial zones of inhibition observed against all tested pathogens. The potent anti-inflammatory activity showed the minimum and maximum inhibition of protein denaturation at concentration of 25 μg/mL and 100 μg/mL are 28% and 69%, respectively. The silver nanoparticles demonstrated anti-inflammatory properties by inhibiting protein denaturation, suggesting their potential therapeutic applications. The mangrove R. mucronata leaf extract decided to be a favorable reducing agent for the biological synthesis of silver nanoparticles with potent antimicrobial activity. [ABSTRACT FROM AUTHOR]

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]

In this study, silver nanoparticles were synthesized using sun-mediated aqueous extract of the stem, flower and leaf of the plant Thymus linearis. The effect of sunlight on extract absorbance is measured using UV–Vis spectroscopy. The resultant nanoparticle F-Ag–NPs, L-Ag–NPs, S-Ag–NPs were characterized using modern techniques including UV–Vis spectroscopy, ATR-FTIR, Zeta potential, Zeta size analyzer, XRD and SEM. The reaction takes place in presence of sunlight and the color changes from light yellow to red finally, dark brown was observed indicating the completion of the reaction. In the case of Flower extract, F-Ag–NPs produced maximum absorbance at a higher concentration of AgN O 3 with lambda max 403, and 405 nm at 5 mM and 10 mM respectively. In the case of stem and leaves extract, maximum absorbance was seen at a low concentration of AgN O 3 with lambda max range from 391 nm to 402 nm and 409–425 nm respectively. The ATR-FTIR spectrum confirms the presence of capping agents which are complemented by a negative zeta potential value. The Zeta sizer revealed the diameter (d-nm) of F-Ag–NPs, L-Ag–NPs, S-Ag–NPs, 73.26, 59.26 and 51.32 respectively. The Ag–NPs also showed anti-bacterial, DDPH, and ABTS activity. The aqueous extract of Thymus linearis (flower, leaves, and stem) was prepared using sunlight. The resultant extract was used as capping, reducing, and stabilizing agent to prepare silver nanoparticles. The Ag–NPs were characterized by using modern characterizing techniques including UV–Vis spectroscopy, FT-IR, zeta-potential, zeta-seizer, SEM, and XRD. The biological studies of Ag–NPs were also performed. [ABSTRACT FROM AUTHOR]

Nanoparticles have gained significant importance due to their small size and effective surface area. Green synthesis of nanoparticles has become a significant tool in material synthesis due to its eco-friendly, economical and less time-consuming aspects. Sweet lime (Citrus sinensis) peel has been used for extract preparation and synthesis of AgNPs. Such nanoparticles have been shown to have excellent anti-microbial and detoxification properties. Though a large number of studies have shown synthesis of AgNP from peel and other parts of C. sinensis, there are no reports of AgNP synthesis from oil extracted from seeds. In this study, oil was extracted from C. sinensis seeds by solvent extraction. The extracted oil was used for the synthesis of AgNPs by bottom-up path approach. The synthesized AgNPs were found to be spherical in shape with size ranging from 30 nm and above. SEM and TEM showed that they are uniformly dispersed particles with no aggregation. Different concentrations of AgNO3 (1 mM, 3 mM and 10 mM) showed distinct UV spectra with UV showing sharp peaks for 10 mM. XRD characterization showed distinct peaks for AgNP when compared to oil extracted. The synthesized AgNPs in this study showed distinct antibacterial activity against E. coli and S. aureus. The AgNPs showed antifungal activity against Pencillium and Rhizopus. Thus, the synthesized AgNPs could be effective antimicrobial agents that could have potential application in food storage and water detoxification. [ABSTRACT FROM AUTHOR]

Research in green synthesis of metallic nanoparticles and their applications in engineering, food, biomedicine and agriculture is growing rapidly. The presence of biologically active metabolites in fungi makes them ideal candidates for green synthesis of silver nanoparticles (AgNPs). This study aims at discerning an emerging applicability of a basidiomycete mushroom, Phaeolus schweinitzii, for mycosynthesis of AgNPs and their antimicrobial properties. The colour change in P. schweinitzii aqueous extract was used to detect and curate the synthesis of AgNPs. The AgNP surface plasmon resonance (SPR) was observed in the visible spectra at approximately 428 nm using UV-Vis spectroscopy. The XRD spectrum revealed a face-centered cubic (FCC) structure of AgNPs with an average crystallite size of 38.78 nm. FT-IR manifested various functional clusters of biomolecules which were involved in bioreduction, capping and stabilization of AgNPs. FE-SEM imaging of AgNPs revealed a spherical shape with an average size of 88.65 nm. The synthesized AgNPs showed strong antimicrobial activities against Salmonella gallinarum, E. coli, Staphylococcus aureus, Aspergillus niger and Fusarium oxysporum with varying zones of inhibition at different concentrations. The highest concentration (5 mg/ml) of AgNPs produced a maximum zone of inhibition (1 3. 3 3 ± 0. 5 7 mm) against gram negative bacteria (Salmonella gallinarum and E. coli) and lowest (1 1. 6 6 ± 0. 5 7 mm) against gram positive bacteria (Staphylococcus aureus). The study also revealed that synthesized AgNPs showed comparatively higher antifungal activity than the positive control (nystatin). The findings from this study explicitly concur with the ever-relevant use of biogenic AgNPs against various pathogenic microorganisms. AgNPs were successfully synthesized using fungal aqueous extract and characterized by various analytical techniques. Biosynthesized AgNPs showed significant growth inhibition of different bacterial and fungal pathogens under test, which infer their application for various biomedical purposes, as well as for food packaging to reduce contamination and enhance long-term storage and preservation of foods. Metal-based nanoparticles such as silver nanoparticles may prove to be very beneficial in the agricultural sector, such as their use as nanopesticides. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are considered an appropriate approach to treat the leishmaniasis in terms of the toxicity and resistance of current anti-leishmanial drugs. This study aimed to prepare stable AgNP and their apoptotic effects on the metabolic activity of Leishmania major. AgNPs were prepared with a green synthesis method using Z. multiflora Boiss (Z. M) extract as a reducing and carboxymethylcellulose (CMC) stabilizer agent. The formation and colloidal stability of AgNPs were shown using ultraviolet-visible absorption spectroscopy during an 80-day period. The average diameter of 4 5. 2 ± 2 3. 5 nm and the surface charge of − 4 2 ± 1 mv were obtained for AgNPs. Furthermore, the toxicity and apoptotic values of AgNPs on Leishmania major were evaluated by MTT assay and flow cytometry, compared with Glucantime ® (meglumine antimoniate) as the current standard medication for leishmaniosis. The results indicated that Z. M extracts coated AgNPs (Z.M@AgNPs) reached IC 5 0 at a 100 μ g/mL concentration, while Glucantime ® reached this point at a concentration of 4000 μ g/mL. The flow cytometry data revealed that the primary mechanism of death in the promastigotes was apoptosis (35.44% for AgNPs and 32.69% for Glucantime ® ). The present findings suggest that Z.M@AgNPs are superior therapeutic agents than Glucantime ® as the positive control group for leishmaniasis treatment. However, further advanced studies are needed to confirm these results. In the current study, silver nanoparticles were prepared with a green synthesis method. The colloidal stability of silver nanoparticles is important for their use in various fields, including medical applications. Therefore, different amounts of CMC were added in the synthesis process, to increase the stability of nanoparticles at least for 3 months in solution. Moreover, the apoptotic effect of these nanoparticles was compared with Glucantime®, which is the most common drug used in the treatment of leishmaniasis. [ABSTRACT FROM AUTHOR]

In this study, a novel medicinal plant, Lagerstroemia indica, was used to extract Silver Oxide Nanoparticles (Ag2O-NPs) and the in vitro anticancer potentials of synthesized Ag2O-NPs were evaluated on human cancer cell lines. Ultraviolet–Visible (UV-Vis) spectroscopy confirmed the formation of Ag2O and the particle size of 9.98 nm was confirmed by X-Ray Diffraction (XRD) analysis. Scanning Electron Microscope (SEM) images showed spherical-shaped NPs. The anticancer potential determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed significant cytotoxic potential against breast cancer (MCF-7) and cervical cancer (HeLa) cell lines with the IC50 concentrations at 46.22 μ g/ml and 39.39 μ g/ml, respectively. Ag2O-NPs showed a subsequent reduction in Mitochondrial Membrane Potential (MMP) and increased level of Reactive Oxygen Species (ROS). The dual staining of Ag2O-NPs showed a greater number of early apoptotic and late apoptotic cells as compared to the standard drug camptothecin. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) determined an upregulated level of Caspase3 and p53. Thus, the present study indicates that Ag2O-NPs synthesized from L. indica may be used as an anti-cancer drug after further in vivo trials. [ABSTRACT FROM AUTHOR]

Eco-friendlybiosynthesis of silver nanoparticles (Ag NPs) and gold (Au NPs) nanoparticles by using Punica granatum and C. reticulata extracts were synthesized efficiently. Ag and Au NPs with sizes 8–10 nm and 30–40 nm were successfully synthesized and extracts serve as capping agents. Forming of NPs was confirmed through UV-visible spectra, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR) studies. The effect of NPs on the luminescence of Eu(TTFA)3 and Sm(TTFA)3 complexes was investigated. Luminescence intensities of the complexes were enhanced several times in the presence of silver and get quenched due to reabsorption of Au NPs. The nonlinear optical properties of NPs were calculated using open aperture Z-scan and degenerate four-wave mixing in the femtosecond region. The toxicity and antimicrobial activities of Ag and Au NPs were studied. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have attracted a great deal of attention in the recent years. It is mostly due to their availability, chemical stability, catalytic activity, conductivity, biocompatibility and anticancer activity. There are three major approaches for AgNPs synthesis; i.e., chemical, physical, and biological methods. Today, many chemical and physical methods have become less popular due to usage of hazardous chemicals or their high costs, respectively. The green method has introduced an appropriate substitute synthesis strategy for the conventional physical and chemical approaches. The utilization of the plant extracts as reducing, stabilizing and coating agent of AgNPs is an interesting eco-friendly approach leading to high efficiency. The anticancer synergistic effects among the AgNPs and phytochemicals will enhance their therapeutic potentials. Surprisingly, although many studies have demonstrated the significant enhancement in cytotoxic activities of plant-mediated AgNPs toward cancerous cells, these nanoparticles (NPs) have been found nontoxic to normal human cells in their therapeutic concentrations. This paper provides a specific insight into the mechanism of plant-mediated AgNPs synthesis, their anticancer and cytotoxic activities in vitro cancer cells, in vivo model animals and clinical trials. [ABSTRACT FROM AUTHOR]

The present work deals with the investigation of the greener route for the production of silver nanoparticles using Raphanus sativus (R. sativus) bioextract in a continuous flow tubular microreactor. The parameters affecting the particle size and distribution were investigated. From the results obtained it can be inferred that the ascorbic acid (reducing agent) present in the R. sativus bioextract is responsible for the reduction of silver ions. At optimum condition, the particle size distribution of nanoparticles is found between 18nm and 39nm. The absorbance value was found to be decreased with an increase in the diameter of the microreactor. It indicates that a number of nuclei are formed in the micrometer sized (diameter) reactor because of the better solute transfer rate leading to the formation of large number of silver nanoparticles. The study of antibacterial activity of green synthesized silver nanoparticles shows effective inhibitory activity against waterborne pathogens, Shegella and Listeria bacteria. [ABSTRACT FROM AUTHOR]