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Bergenia ciliata (BC) is a perennial herb that is frequently used as a traditional medicine. Its leaves and rhizomes are reported to have significant antioxidant, metal-reducing, and chelating properties. Although the rhizomes have the potential to synthesize silver nanoparticles (AgNPs), the leaves are yet to be studied for the green synthesis of metal nanoparticles. Likewise, photoirradiation also plays a significant role in the green synthesis of metal nanoparticles. In the current study, we intended to demonstrate the implications of photoirradiation by white light-emitting diode (LED) on the aqueous and methanol extracts (AE and ME, respectively) of BC leaf-mediated green synthesis of AgNPs. In this regard, the AgNP synthesis of the two extracts was performed in the dark and under 250-lumen (lm) and 825 lm LED bulbs. The physicochemical characterization of the synthesized nanoparticles was also performed, wherein percent nanoparticles yield, morphology of the nanoparticles, shape, size, percent elemental composition, crystallinity, and nanoparticle stability were studied. The nanoparticle-synthesizing potential of the two extracts contradicted significantly in the presence and absence of light, while the AE produced a significantly high number of nanoparticles in the dark (17.26%), and increasing light intensities only attenuated the nanoparticle synthesis, whereas ME synthesized comparatively negligible silver nanoparticles in the dark (1.23%). However, increasing light intensities significantly enhanced the number of nanoparticles synthesized in 825 lms (7.41%). The GCMS analysis further gave a comparative insight into the phytochemical composition of both extracts, wherein catechol and pyrogallol were identified as major reducing agents for nanoparticle synthesis. The influence of light intensities on the physiochemical characterization of AgNPs was predominant. While the size of both the AE- and ME-mediated AgNPs increased considerably (20–50 nm diameter) with increasing light intensities, the percent of silver atoms decreased significantly with increasing light intensities in both the AE- and ME-mediated AgNPs with ranges of 13–18% and 14–24%, respectively. The nanoparticle stability studies suggested that both the AE- and ME-mediated AgNPs were stable for up to 15 days when stored at 4 °C. The stability of both nanoparticles was attributed to the presence of a wide range of phytochemicals. In conclusion, the AE of BC leaves was reported to have significantly higher AgNP-synthesizing potential as compared to the ME. However, AE-mediated AgNP synthesis is attenuated by photoirradiation, whereas ME-mediated AgNP synthesis is enhanced by photoirradiation. The photoirradiation by white LED light increases the size of the AgNPs, while the percent silver composition declines, irrespective of the extract type. Both extracts, however, have nanoparticle stabilizing potential, thereby producing stable nanoparticles. [ABSTRACT FROM AUTHOR]

The present work aims to study the possibilities of developing silver nanoparticles using natural extracts of grape pomace wastes originating from the native variety of Fetească Neagră 6 Șt. This study focused on investigating the influence of grape pomace extract obtained by two different extraction methods (classical temperature extraction and microwave-assisted extraction) in the phytosynthesis process of metal nanoparticles. The total phenolic content of the extracts was assessed using the spectrophotometric method with the Folin–Ciocâlteu reagent, while the identification and quantification of specific components were conducted through high-performance liquid chromatography with a diode array detector (HPLC-DAD). The obtained nanoparticles were characterized by UV–Vis absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), along with assessing their antioxidant and antimicrobial properties against Gram-positive bacteria. The data collected from the experiments indicated that the nanoparticles were formed in a relatively short period of time (96 h) and, for the experimental variant involving the use of a 1:1 ratio (v/v, grape pomace extract: silver nitrate) for the nanoparticle phytosynthesis, the smallest crystallite sizes (from X-ray diffraction—4.58 nm and 5.14 nm) as well as spherical or semispherical nanoparticles with the lowest average diameters were obtained (19.99–23 nm, from TEM analysis). The phytosynthesis process was shown to enhance the antioxidant properties (determined using the DPPH assay) and the antimicrobial potential (tested against Gram-positive strains) of the nanoparticles, as evidenced by comparing their properties with those of the parent extracts; at the same time, the nanoparticles exhibited a selectivity in action, being active against the Staphylococcus aureus strain while presenting no antimicrobial potential against the Enterococcus faecalis strain. [ABSTRACT FROM AUTHOR]

Nanotechnology is developing into a fast-expanding discipline with applications in science and technology, and nanostructures are a crucial research tool in many fields. Due to their remarkable electrical, optical, magnetic, catalytic, and pharmacological capabilities, metal and metal oxide nanoparticles (NPs) have drawn study interest. Natural elements (plants, microorganisms, fungi, etc.) are utilized in a chemical-free, environmentally benign way to synthesize metals and metal oxides. The optical, electrical, and antimicrobial qualities of silver nanoparticle (AgNP) make them a popular choice. More than 200 active ingredients, including water-soluble, organic-soluble, and volatile chemicals, are found in Ganoderma. The main components are polysaccharides, adenosine, and terpenoids, each of which has exceptional therapeutic properties. This article explains the synthesis of Ag NPs by Ganoderma lucidum and tests the antibacterial effectiveness for use in biological 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]

Green synthesis offers a superior alternative to traditional methods for producing metal and metal oxide nanoparticles. This approach is not only benign and safe but also cost-effective, scalable, and straightforward, operating under ambient conditions. Notable metals and metal oxide nanoparticles, such as manganese oxides, iron oxides, silver, and gold, have been produced using various bio-reductants derived from plant extracts. These biological agents not only expedite the reduction process but also stabilize the nanoparticles, serving dual roles as reducing and capping agents. This review presents the green synthesis of nanoparticles (NPs) obtained from biogenic wastes and plant extracts. The green-synthesized nanostructured MnO2 nanoparticles are evaluated as a potential photocatalyst for water treatment and as an electrode material in lithium-ion batteries and supercapacitors. The green-derived iron oxide nanoparticles are examined as promising antioxidant, anti-inflammatory, and anti-diabetic agents. Additionally, this review discusses the green synthesis of precious metal nanoparticles, specifically silver (Ag NPs) and gold (Au NPs), highlighting their potential medical applications in areas like antiviral treatments and cancer therapy. [ABSTRACT FROM AUTHOR]

This study delves into the novel utilization of Aristolochia manshuriensis cultured cells for extracellular silver nanoparticles (AgNPs) synthesis without the need for additional substances. The presence of elemental silver has been verified using energy-dispersive X-ray spectroscopy, while distinct surface plasmon resonance peaks were revealed by UV-Vis spectra. Transmission and scanning electron microscopy indicated that the AgNPs, ranging in size from 10 to 40 nm, exhibited a spherical morphology. Fourier-transform infrared analysis validated the abilty of A. manshuriensis extract components to serve as both reducing and capping agents for metal ions. In the context of cytotoxicity on embryonic fibroblast (NIH 3T3) and mouse neuroblastoma (N2A) cells, AgNPs demonstrated varying effects. Specifically, nanoparticles derived from callus cultures exhibited an IC50 of 2.8 µg/mL, effectively inhibiting N2A growth, whereas AgNPs sourced from hairy roots only achieved this only at concentrations of 50 µg/mL and above. Notably, all studied AgNPs' treatment-induced cytotoxicity in fibroblast cells, yielding IC50 values ranging from 7.2 to 36.3 µg/mL. Furthermore, the findings unveiled the efficacy of the synthesized AgNPs against pathogenic microorganisms impacting both plants and animals, including Agrobacterium rhizogenes, A. tumefaciens, Bacillus subtilis, and Escherichia coli. These findings underscore the effectiveness of biotechnological methodologies in offering advanced and enhanced green nanotechnology alternatives for generating nanoparticles with applications in combating cancer and infectious disorders. [ABSTRACT FROM AUTHOR]

Nanoparticles (1 to 100 nm) have unique physical and chemical properties, which makes them suitable for application in a vast range of scientific and technological fields. In particular, metal nanoparticle (MNPs) research has been showing promising antimicrobial activities, paving the way for new applications. However, despite some research into their antimicrobial potential, the antimicrobial mechanisms are still not well determined. Nanoparticles' biosynthesis, using plant extracts or microorganisms, has shown promising results as green alternatives to chemical synthesis; however, the knowledge regarding the mechanisms behind it is neither abundant nor consensual. In this review, findings from studies on the antimicrobial and biosynthesis mechanisms of MNPs were compiled and evidence-based mechanisms proposed. The first revealed the importance of enzymatic disturbance by internalized metal ions, while the second illustrated the role of reducing and negatively charged molecules. Additionally, the main results from recent studies (2018–2022) on the biosynthesis of MNPs using microorganisms were summarized and analyzed, evidencing a prevalence of research on silver nanoparticles synthesized using bacteria aiming toward testing their antimicrobial potential. Finally, a synopsis of studies on MNPs applied to cultural heritage materials showed potential for their future use in preservation. [ABSTRACT FROM AUTHOR]

The synthesis of nanoparticles using medicinal plants is a potential pathway for developing environmentally friendly drugs with minimal side effects. The aim of this study was to isolate heptadecyl-trans-p-coumarate from the medicinal plant, Artemisia afra, utilise it and its extract to synthesise silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnONPs) and iron oxide nanoparticles (Fe2O3NPs) that were evaluated for antibacterial and cytotoxic activity. AgNPs synthesised from the coumarate and extract were mostly spherical with an average size of 12 nm and 29 nm, respectively. ZnONPs were mostly rods, plates and spheres with average sizes of 31 nm (extract) and 22 nm (coumarate). Fe2O3NPs were hexagons and spheres with average sizes of 31 nm (extract) and 24 nm (coumarate). Nanoparticles improved the antibacterial activity of the extract and coumarate against Escherichia coli, Pseudomonas aeruginosa, Chromobacterium violaceum and Staphylococcus aureus. Shape of nanoparticles influenced activity; rod-shaped ZnONPs and platelet-like Fe2O3NPs synthesised using the extract exhibited better antibacterial activity. Spherical ZnONPs synthesised using the coumarate and spherical AgNPs showed greater cytotoxicity. The results suggest a synergistic effect between the metal nanoparticles and capping agents. Overall, this study confirms the use of Artemisia afra for the biosynthesis of silver, zinc oxide and iron oxide nanoparticles. [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]

Leucus aspera is a perennial plant traditionally used as an herbal medicine in many countries. The biosynthesis of metal nanoparticles using medicinal plants is not only economical but also environmentally friendly as well as having miscellaneous biomedical applications. In this study, Leucus aspera extract as a stabilising and reducing agent was utilised to synthesise Ag nanoparticles in the aqueous medium. In addition, the anti-alveolar cancer property of AgNPs was investigated in the in vitro condition. Various techniques containing UV–Vis. spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS) were used to characterise the synthesised nanoparticles. On the other hand, the MTT assay was run to evaluate the cytotoxicity activity of AgNPs. The crystal size of AgNPs, according to the XRD analysis, was 34.22 nm. Moreover, the uniform spherical morphology ranging from 40.67 to 58.17 nm was detected in the SEM images for the biosynthesised nanoparticles. In the antioxidant test, the IC50 of AgNPs and BHT against DPPH free radicals were 87 and 41 µg/mL, respectively. The synthesised nanocomposite had very low cell viability and high anti-alveolar cancer activities against A549 cell line without any cytotoxicity on the normal cell line (HUVEC). The viability of malignant alveolar cell line reduced dose-dependently in the presence of Ag NPs. Perhaps notable anti-alveolar cancer activities of the synthesised nanocomposite against common alveolar cancer cell line are linked to their antioxidant activities. [ABSTRACT FROM AUTHOR]

Plant fractions have a diversity of biomolecules that can be used to make complicated reactions for the bioactive fabrication of metal nanoparticles (NPs), in addition to being beneficial as antioxidant medications or dietary supplements. The current study shows that Urtica dioica (UD) and biologically synthesized silver nanoparticles (AgNPs) of UD have antibacterial and antioxidant properties against bacteria (Escherichia coli and Pseudomonas putida) and Drosophila melanogaster (Oregon R+). According to their ability to scavenge free radicals, DPPH, ABTS, TFC, and TPC initially estimated the antioxidant potential of UD and UD AgNPs. The fabricated AgNPs were analyzed (UV–Vis, FTIR, EDS, and SEM) to determine the functional groups (alcohol, carboxylic acids, phenol, proteins, and aldehydes) and to observe the shape (agglomerated crystalline and rod-shaped structure). The disc diffusion method was used to test the antimicrobial properties of synthesized Ag-NPs against E. coli and P. putida. For 24 to 120 h, newly enclosed flies and third instar larvae of Drosophila were treated with UD and UD AgNPs. After exposure, tests for biochemical effects (acetylcholinesterase inhibition and protein estimation assays), cytotoxicity (dye exclusion), and behavioral effects (jumping and climbing assays) were conducted. The results showed that nanoparticles were found to have potent antimicrobial activity against all microbial strains tested at various concentrations. In this regard, ethno-medicinal characteristics exhibit a similar impact in D. melanogaster, showing (p < 0.05) significantly decreased cellular toxicity (trypan blue dye), enhanced biochemical markers (AChE efficacy and proteotoxicity), and improved behavioral patterns in the organism treated with UD AgNPs, especially in comparison to UD extract. The results of this study may help in the utilization of specific plants as reliable sources of natural antioxidants that may have been beneficial in the synthesis of metallic NPs, which aids in the production of nanomedicine and other therapeutic applications. [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]

Green synthesis reduces the production of deleterious products through sustainable and eco-friendly synthesis procedures by using natural resources such as green materials. The present work reports the green synthesis of metal nanoparticles to minimise waste products and implement sustainable processes. Environmental sustainability will increase the healthy environment by reducing hazardous products to the environment. The research community attracts green plants and their products for materials production due to their nontoxic nature to the environment and human health. The current report is new experimentation for nanoparticles by use of green materials with biological reduction method. Silver and gold nanoparticles were synthesized by use of Butea monosperma plant leaves extract. Potential applications of the green derived nanoparticles are known for biological applications and environmental remediation is discussed. The mechanisms of the biological activity of the nanoparticles are also reported. [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]

The ZnO, MgO, NiO, and AlO nanoparticles and Zn–Al and Mg–Ni composite oxides were synthesized by the green method from the Prunus persica leaves extract. The synthesized nanoparticles were characterized through FT-IR, XRD, SEM, and TEM. The FT-IR study was carried out to find out the presence of various functional groups in nanoparticles. Their size was studied by the XRD method which exposed that the nanoparticles were in the range of 19–29 nm, and the size and morphology were studied by SEM, which was further confirmed by TEM. The synthesized nanoparticles were tested for antibacterial activity. In particular, ZnO showed a good inhibitory effect with 22.31 mm of inhibition against Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

The multifunctional features of noble metal nanoparticles (MNPs) were exploited in various biomedical applications, which eventually demanded the development of a sustainable green synthesis approach. In the present study, Quercetin (Q) was employed as a promising green reductant for the generation of noble metal nanoparticles such as silver (Q-AgNPs), gold (Q-AuNPs), and bimetallic (Q-Ag-AuNPs) towards biomedical perspective. Initially, the NPs were successfully synthesized in a size-controlled manner via optimizing temperature, pH, metal ion concentration, and stoichiometric ratio of the reaction mix. The redox reaction and conversion of metal ions (Ag+ and Au3+) into their respective metal nano-forms were confirmed through their surface plasmonic resonance (SPR) in UV-visible spectroscopy. In addition, different instrumentation like FT-IR, XRD, HR-TE M, and XPS analyses were performed to confirm the size, shape, and chemical composition of fabricated NPs. The bactericidal effect of fabricated NPs was tested against Gram-positive and Gram-negative pathogens. Moreover, the cytotoxic potential was screened against breast (MCF-7) and colorectal (HCT-116) carcinoma cell lines. This work revealed that the flavonoid-functionalized noble metal NPs were associated with good antibacterial and anticancer potential against selected cancer cell lines. [ABSTRACT FROM AUTHOR]

Large amounts of spent coffee grounds (SCGs) are produced annually worldwide. SCGs contain high levels of phenolics and other bioactive compounds that make them a potential source of reducing and stabilizing agents for the synthesis of metal nanoparticles. This study investigates the use of SCG extracts as a green strategy to produce silver nanoparticles (AgNPs). SCG extracts were obtained using aqueous ethanol as the solvent and then contacted with a silver nitrate solution under the selected conditions. A central composite design coupled with response surface methodology was used to evaluate the effects of solvent composition (C = 30–70% v/v), silver-to-phenolic ratio (R = 3–7 mol/mol), temperature (T = 25–55 °C) and pH (10–12) on the production of AgNPs. Characterization of AgNPs by DLS, TEM and XRD techniques showed that they were highly crystalline with a narrow size distribution. Under optimal reaction conditions, AgNPs with an average size of about 10 nm and a zeta potential of −30.5 to −20.7 mV were obtained. Overall, the results of this study indicate that SCGs are a promising material for the green synthesis of small-sized and stable AgNPs. [ABSTRACT FROM AUTHOR]

The accumulation of organic contaminants including dyes in aquatic systems is of significant environmental concern, necessitating the development of affordable and sustainable materials for the treatment/elimination of these hazardous pollutants. Here, a green synthesis strategy has been used to develop a self-assembled gum kondagogu-sodium alginate bioconjugate sponge adorned with silver nanoparticles, for the first time. The properties of the nanocomposite sponge were then analyzed using FTIR, TGA, SEM, and MicroCT. The ensued biobased sponge exhibited hierarchical microstructure, open cellular pores, good shape memory, and mechanical properties. It merges the attributes of an open cellular porous structure with metal nanoparticles and are envisaged to be deployed as a sustainable catalytic system for reducing contaminants in the aqueous environment. This nanocomposite sponge showed enhanced catalytic effectiveness (km values up to 37 min−1 g−1 and 44 min−1 g−1 for methylene blue and 4-nitrophenol, respectively), antibacterial properties, reusability, and biodegradability (65% biodegradation in 28 days). [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are well known to have antimicrobial activity, but very little is known about the effect of AgNPs on various enzyme activities. They (AgNPs) are valuable metal nanoparticles that exhibit exceptional properties compared to their bulk materials. Humulus lupulus L. (hops) is an important medicinal aromatic plant used in industry. It has many compounds such as phenolic, flavonoids, tannins, etc. In this study, green syntheses of Humulus lupulus L. based silver nanoparticles were performed. Accordingly, it was determined that HL-AgNPs gave maximum absorbance at approximately 450 nm and nanoparticle sizes ranged from 30.60 nm to 36.72 nm. The potential peaks of the prepared aqueous extract and HL-AgNPs were determined using FTIR-ATR. It was determined that the synthesized nanoparticles gave 2296.89 cm-1, 1161.05 cm-1, 1112.34 cm-1 peaks. Total phenolic content of HL-AgNPs was determined as 30.62 ±0.02 mg GAE/mL, and DPPH· radical scavenging activity IC50 value was determined as 4.4 ±0.01 mg/mL. Inhibitory effects of HL-AgNPs on α-amylase, α-glycosidase and urease enzymes were studied and IC50 values were determined as 3.10 ±0.01 mg/mL, 9.42 ±0.02 mg/mL and 0.76 ±0.01 mg/mL, respectively. The synthesized Humulus lupulus L. based silver nanoparticles showed better biochemical activity than the prepared Humulus lupulus L. aqueous extract. It is clear that it is possible to use HL-AgNPs obtained by green synthesis in various biomedical applications. [ABSTRACT FROM AUTHOR]

The alarming effect of antibiotic resistance prompted the search for alternative medicine to resolve the microbial resistance conflict. Over the last two decades, scientists have become increasingly interested in metallic nanoparticles to discover their new dimensions. Green nano synthesis is a rapidly expanding field of interest in nanotechnology due to its feasibility, low toxicity, eco‐friendly nature, and long‐term viability. Some plants have long been used in medicine because they contain a variety of bioactive compounds. Silver has long been known for its antibacterial properties. Silver nanoparticles have taken a special place among other metal nanoparticles. Silver nanotechnology has a big impact on medical applications like bio‐coating, novel antimicrobial agents, and drug delivery systems. This review aims to provide a comprehensive understanding of the pharmaceutical qualities of medicinal plants, as well as a convenient guideline for plant‐based silver nanoparticles and their antimicrobial activity. [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]

Nanoparticles exhibiting the localized surface plasmon resonance (LSPR) phenomenon are promising tools for diagnostics and cancer treatment. Among widely used metal nanoparticles, silver nanoparticles (Ag NPs) possess the strongest light scattering and surface plasmon strength. However, the therapeutic potential of Ag NPs has until now been underestimated. Here we show targeted photothermal therapy of solid tumors with 35 nm HER2-targeted Ag NPs, which were produced by the green synthesis using an aqueous extract of Lavandula angustifolia Mill. Light irradiation tests demonstrated effective hyperthermic properties of these NPs, namely heating by 10 °C in 10 min. To mediate targeted cancer therapy, Ag NPs were conjugated to the scaffold polypeptide, affibody ZHER2:342, which recognizes a clinically relevant oncomarker HER2. The conjugation was mediated by the PEG linker to obtain Ag-PEG-HER2 nanoparticles. Flow cytometry tests showed that Ag-PEG-HER2 particles successfully bind to HER2-overexpressing cells with a specificity comparable to that of full-size anti-HER2 IgGs. A confocal microscopy study showed efficient internalization of Ag-PEG-HER2 into cells in less than 2 h of incubation. Cytotoxicity assays demonstrated effective cell death upon exposure to Ag-PEG-HER2 and irradiation, caused by the production of reactive oxygen species. Xenograft tumor therapy with Ag-PEG-HER2 particles in vivo resulted in full primary tumor regression and the prevention of metastatic spread. Thus, for the first time, we have shown that HER2-directed plasmonic Ag nanoparticles are effective sensitizers for targeted photothermal oncotherapy. [ABSTRACT FROM AUTHOR]

Among the most notable nanotechnology applications is its employment in environmental remediation and biomedical applications. Nonetheless, there is a need for cleaner and sustainable methods in preparing nanomaterials that use cheaper, more environment-friendly precursors than the conventional synthesis process. The green chemistry approach for the preparation of nanoparticles is becoming more attractive as it uses non-toxic chemicals and reagents. It also offers cost-effective synthesis process as it uses readily available plant sources and microbe as redox mediators in converting metallic cations to metal or metal oxide nanoparticles. The extracts of these plants and microbe sources contain phytochemicals and metabolites in variable quantities, which serve as redox mediators and capping agents that stabilize the biosynthesized nanoparticles. The present article reviews the recent studies on the fabrication of silver oxide nanoparticles (Ag2O-NPs) via plant-mediated and microbe-mediated green synthesis, giving a concise discussion on the green preparation of Ag2O-NPs employing extracts of different plants and microbial sources. The performances of the biosynthesized Ag2O-NPs are also reviewed, highlighting their potential use in photocatalysis and biomedical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Caralluma adscendens R.Brown var. bicolor was used for the phytosynthesis of nanomaterials. • Both nanoparticles exhibited greater pharmacological activities. • Prepared nanomaterials were characterized using FTIR, HR-TEM, EDX, and UV–Vis analysis. • Both nanoparticles showed higher wound-healing activity than CABL extract based on the MTT assay and fluorescence analysis. Nanomaterials employed in nanomedicine have the potential to function as both diagnostic and therapeutic tools for individuals. Over the past few decades, significant efforts have been made to synthesize a range of metal nanoparticles through the utilization of different plant extracts. Caralluma adscendens R. Brown var. bicolor leaves (CABL) extract was employed in this study as a reducing/capping agent for the synthesis of gold/silver nanoparticles (CABL@AgNPs/CABL@AuNPs) and explore their pharmacological properties. The successful synthesis of CABL@AgNPs and CABL@AuNPs was confirmed through the observation of surface plasmon resonance (SPR) at 439 and 522 nm using ultraviolet–visible spectrophotometer (UV–Vis). High resolution-transmission electron microscopy (HR-TEM) and energy dispersive X-ray (EDX) techniques were employed to evaluate the shape, size, and chemical composition of the as-synthesized CABL@AgNPs and CABL@AuNPs. Fourier-transform infrared spectroscopy (FTIR) was used to determine the biomolecules responsible for the reduction of metal ions and the stability of metal nanoparticles generated using plant extract. An evaluation was performed to assess the antibacterial and antifungal efficacy of the prepared aqueous CABL extract, CABL@AgNPs, and CABL@AuNPs through the implementation of the disc diffusion technique. The results demonstrated that CABL@AgNPs exhibited greater efficiency when compared to both CABL extract and CABL@AuNPs. The dose-dependent nature of antimicrobial activities was clearly demonstrated through the results of antioxidant and anti-inflammatory experiments. The wound healing activity of the prepared nanomaterials was evaluated using a variety of techniques, including MTT assay, fluorescence staining test, and in vitro scratch assay. The wound-healing capacity of prepared nanomaterials was evaluated using an in vitro scratch assay with Fibroblast L929 cells. The impact of nanoparticles at the IC 50 concentration range was analysed through a fluorescence staining experiment and MTT assay to determine toxicity levels. The environmentally friendly approach of current study shown that both nanoparticles have the potential to be effective therapeutic agents for treating different illnesses. [ABSTRACT FROM AUTHOR]

Biosynthesis of nanoparticles is the preferred route for the fabrication of biocompatible and cheaper drugs. In this study, the extract and major secondary metabolite from Helichrysum aureonitens, 3,5-dihydroxy-6,7,8-trimethoxyflavone, were used to synthesize silver and zinc oxide nanoparticles. Spectroscopic and microscopic techniques confirmed the formation of the nanoparticles. The flavone alone showed higher DPPH radical scavenging ability (IC50 = 487.1 μg mL−1) relative to the control, butylated hydroxytoluene. In addition, silver nanoparticles synthesized using the flavone had higher ferric reducing potential (Fe3+ to Fe2+) compared to the other test samples. The cytotoxic activity of the plant extract, the flavone, and their biosynthesized nanoparticles was also investigated using the MTT assay against the cancerous MCF-7 (breast adenocarcinoma) and A549 (human lung adenocarcinoma)), and non-cancerous HEK293 (human embryonic kidney) cell lines. The plant extract decreased the cell viability of A549 (IC50 = 68.6 μg mL−1) without being cytotoxic against HEK293, even at high concentrations. Silver nanoparticles significantly decreased cell viability of A549 and moderately decreased cell viability of MCF-7 but induced cell death of HEK293 even at low concentrations. This study provides a green synthesis route for silver and zinc oxide nanoparticles and confirms the therapeutic effectiveness of H. aureonitens, thereby validating its use in ethnomedicine. [ABSTRACT FROM AUTHOR]

Plant extract-based green synthesis of metal nanoparticles (NPs) has become a popular approach in the field of nanotechnology. In this present investigation, silver nanoparticles were prepared by an efficient and facile approach using Juniperus procera extract as a bioreducing and stabilizing agent. The as-synthesized silver nanoparticles (JP-AgNPs) were characterized by several characterization techniques such as UV–Vis, XRD, FT-IR, HR-TEM, and EDX analysis. The XRD analysis evidently confirms that the as-synthesized Ag nanoparticles (NPs) from Juniperus procera plant extract (JP-AgNPs) are crystalline in nature. FT-IR analysis confirms that the plant extract plays a dual role as a bioreducing and capping agent, while HR-TEM revealed the spherical morphology of as-synthesized JP-AgNPs with the size of ~23 nm. Furthermore, the synthesized JP-AgNPs were evaluated for antibacterial properties against several bacterial and fungal strains such as Staphylococcus aureus (ATCC 12228), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Proteus mirabilis (ATCC 4753), Cryptococcus neoformans (ATCC 16620), and Candida albicans (ATCC 885-653). The JP-AgNPs displayed an efficient mean zone of inhibition (MZI) at 50.00 µL for bacterial associated with fungal pathogens than the plant extract. Mainly, MZI values against microbial pathogens were as follows; E. coli (17.17 ± 0.72 mm), P. mirabilis (14.80 ± 0.17 mm), and C. albicans (14.30 ± 0.60 mm), whereas JP-AgNPs showed moderate activity against P. aeruginosa (11.50 ± 0.29 mm) and C. neoformans (9.83 ± 0.44 mm). Notably, the tested JP-AgNPs have displayed almost similar antimicrobial activities with that of standard antimicrobial drugs, such as streptomycin and nystatin. The enhanced antimicrobial activity of JP-AgNPs can be ascribed to the quality of resultant NPs including, uniform size, shape, and aqueous colloidal stability of nanoparticles. [ABSTRACT FROM AUTHOR]

In recent year green and eco-friendly synthesis of metal nanoparticles plays an important role in nanotechnology, medical science, industries, ceramics etc. The manuscript focuses on the green and facile synthesis of AgNPs from aqueous solution of leaf of Cassia fistula. UV-Visible spectra confirm the bio-formation of AgNPs at 412 nm with the witness of change in colour. Synthesized silver nanoparticle characterized further by FTIR, SEM, EDX and XRD spectroscopic technique. The shape of AgNPs is observed to be like oval, triangular and cylindrical respectively. EDX analysis confirmed the elemental percentage of silver 93.02%. FTIR shows shifting in bands from lower side to upside. The biosynthesized AgNPs shows antibacterial activity against E. coli and B. subtilis pathogens and it was found that AgNPs were more effective against E. coli and B. subtilis bacteria. The method used in this study for the biosynthesis of AgNPs from aqueous extracts of Cassia Fistula was green, reduce harmful chemical with no environmental hazards. [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]

Plant extracts are a good alternative of reducing agents in the synthesis of metal nanoparticles. In this paper, we report the evaluation of the cytotoxic activity against T3 cell lines of the ethanolic extract of Monteverdia salicifolia (Mart ex. Reissek) Biral roots (MS) as well as a green one-pot route of synthesis of silver nanoparticles (AgNPs) using that extract as reducing and stabilizing agent. The extract exhibited dose dependent activity. The smallest particle size (48.01 nm) was achieved in just 25 minutes by employing a temperature of 65 °C and AgNO3 and MS concentrations equal to 0.9 mmol.L-1 and 0.67 mg.mL-1, respectively. The AgNPs-MS nanocomposite was characterized by UV-vis spectroscopy, FEG microscope and zeta potential, which proved that MS was effective at reducing and capping the AgNPs. In order to emphasize the advantage of the methodology applied in this synthesis, it was compared to a usual procedure using NaBH4 as a reducing agent and the greenness analysis was also carried out, using the Green Star. [ABSTRACT FROM AUTHOR]

The wide use of metal nanoparticles has raised the concern of their release in the environment and their biological safety. The use of silver nanoparticles (Ag NPs) as effective antimicrobial agent is also questioned due to the resistance developed by pathogens and the biosafety for the host. The genotoxicity caused by such particles need to be assessed to ensure that they are safe to use. In this study, green synthesized Ag NPs were used and the biosafety in terms of genotoxicity was evaluated by in vitro Chromosome aberration (CA) assay using short-term cultures of human peripheral blood. The physicochemical parameters of these Ag NPs were studied for stability in nano form. The transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) were carried out. The dynamic light scattering and zeta potential measurements revealed stable nano particles. The UV visible & fluorescence spectroscopy for binding affinity of Ag NPs did not suggest significant DNA interaction. The exposure of whole blood cultures to Ag NPs for 24 h showed dose dependent increase in frequency of CA per cell at 350, 650 and 1000 µL (P = NS, P < 0.05 and P < 0.001 respectively). Our study demonstrates that genotoxicity of Ag NPs can be reduced by the use of green synthesized Ag NPs at low dose exposure, which will guide selecting right concentrations of NP for further in vivo studies, and future applications. [ABSTRACT FROM AUTHOR]

The scientific community has paid special attention to silver nanoparticles (AgNPs) in recent years due to their huge technological capacities, particularly in biomedical applications, such as antimicrobials, drug-delivery carriers, device coatings, imaging probes, diagnostic, and optoelectronic platforms. The most popular method of obtaining silver nanoparticles as a colloidal dispersion in aqueous solution is chemical reduction. The choice of the capping agent is particularly important in order to obtain the desired size distribution, shape, and dispersion rate of AgNPs. Gemini alkylammonium salts are named as multifunctional surfactants, and possess a wide variety of applications, which include their use as capping agents for metal nanoparticles synthesis. Because of the high antimicrobial activity of gemini surfactants, AgNPs stabilized by this kind of surfactant may possess unique and strengthened biocidal properties. The present paper presents the synthesis of AgNPs stabilized by gemini surfactants with hexadecyl substituent and variable structure of spacer, obtained via ecofriendly synthesis. UV-Vis spectroscopy and dynamic light scattering were used as analyzing tools in order to confirm physicochemical characterization of the AgNPs (characteristic UV-Vis bands, hydrodynamic diameter of NPs, polydispersity index (PDI)). [ABSTRACT FROM AUTHOR]

The green approachable of metal nanoparticles is treated to be an eco-friendly path and cost-effectiveness. In this present study, nano copper was synthesized profitably by Cissus vitiginea. The synthesized nano copper was used to evaluate the antioxidant and antibacterial activity against urinary tract infections pathogens. The resulting constructed nanoparticles were characterized by using ultraviolet spectroscopy absorbance around 370 nm. Scanning electron microscopy results showed the distribution of nanoparticles and particles sizes are found to be in the range of 5–20 nm. X-ray diffraction spectrum characteristic diffraction peaks for copper nanoparticles were observed at 2θ ranges 35.5 and 43.2° correspond to lattice planes (1 1 1) and (2 0 2), respectively. X-ray photoelectron spectroscopy shows that two distinct peaks at binding energy resulted that the chemical states of copper. The results serve the evidence that the green mediated nano copper might indeed be the potential source to treat urinary tract infections caused by E. coli, Enterococcus sp., Proteus sp. and Klebsiella sp. This fact-finding conclusion is that C. vitiginea leaf extract based green synthesis nano copper particles proved to effectively kill it or significantly inhibit activity contra to urinary tract infection pathogens and exhibit excellent antioxidant activity. [ABSTRACT FROM AUTHOR]

Nature has a massive range of diverse species of flora. The phytochemical content of each plant may vary due to the diverse climate and different geographical areas. Several plants have been outlined for their reducing properties and highly exploited for the green synthesis of metal nanoparticles. Moreover, phytochemicals present in plant parts (leaf, root, flower, fruit, etc.) act as both reducing and capping agents for the production of nanoparticles. Plant-mediated nanoparticles have gained so much attention in the present era for its green and rational approach and developed as a green substitute to conventional synthesis approaches. This critical review encloses literature, phytosynthesis methods, and factors affecting the synthesis of silver nanoparticles. Also, the main characterization techniques especially, spectroscopic techniques are epigrammatically summarized and discussed here. [ABSTRACT FROM AUTHOR]

[Display omitted] • Echinophora platyloba was used as source for plant extract for synthesis of AgNPs. • pH and temperature were found effective on the size of AgNPs. • Kinetic of nanoparticle growth were determined by pH of plant extract. • AgNPs showed promising performance as catalyst for degradation of complex dyes. • AgNPs showed antibacterial properties against both gram-negative and gram-positive bacetria. Green synthesis of nanomaterials for environmental application is a double win approach for environment and humanity. In this work, we present how silver nanoparticles (AgNPs) could be synthesized using Echinophora platyloba (E.P) plant extract as an environmentally friendly source, which acts as both reducing agent and capping agent for synthesis of small-sized AgNPs with maximum antibacterial and catalytic efficacy. The as-synthesized AgNPs were characterized by UV–Visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. The size of AgNPs were fine-tuned by adjusting the synthesis parameters such as pH of plant extract, temperature, and amount of AgNO 3. It was found that pH is a determining factor, where the size of AgNPs could be tuned from 15 nm to 53 nm by decreasing the pH from 10 to 7. In addition, the kinetic of growth was found pH-dependent, where small-sized AgNPs grow faster than large ones, culminating in shortening reaction time at alkaline pH. Green synthesized AgNPs (15 nm) showed remarkable catalytic performance in degradation of different individual azo dyes (i.e., Congo red (CR), Rhodamine B (Rh), methyl red (MR), bromocresol blue (BCB), Imido Black (IB)) as well as their mixture. It was found that the 90.11 % of mixture of dyes were decomposed in 8 min, following a pseudo-first order kinetic model. In addition, the antibacterial activity of the as-synthesized AgNPs (15 nm) was obtained against both gram-positive and gram-negative bacteria. The minimum inhibitory concentration (MIC) was found to be 119.06 µg/mL of silver nanoparticles for Escherichia coli (G-) and 59.53 µg/mL for Staphylococcus aureus (G +). The results of this work emphasize on how a cost-effective and green approach could be used for environmental application and affect circular economy by its potential future applications in medical and environmental fields. [ABSTRACT FROM AUTHOR]

In the storyline of metal nanoparticles, green synthesis is emerging at a very fast pace. In this experimentation phenomena, nanoparticles of Titanium dioxide were coalesced using an extract solution of oscimum sanctum herba as a bioreductant. This is novel and interesting method for synthesis of TiO2 nanoparticles. The prepared titanium dioxide nanoparticles were distinguished using ultraviolet-visible spectroscopy (UV-VIS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM). The girth range of TiO2 nanoparticles was evaluated to be in the range of 90-100 nm. Moreover, the reaction which was alkaline by behavior of the solution (pH = 8) resulted in the increase in absorbance (at 570 nm and 490 nm), which sparges the growth of the number of TiO2 nanoparticles in the studied solution. The microscopic technique showed that the diameter of TiO2 was in the range of 6-10 nm but with little agglomeration. Also, its Antibiofilm activity was accessed with correlation to optical densities, biofilm formation capability of microbes make their distortion tedious but fighting strategy of nanoparticles could be a revolution in antibacterial investigations 450 µg/l of nanoparticles from both the extracts targeted the biofilms of E.coli. [ABSTRACT FROM AUTHOR]

The metal nanoparticles, due to interesting features such as electrical, optical, chemical and magnetic properties, have been investigated repeatedly. Also, the mentioned nanoparticles have specific uses in terms of their antibacterial activity. The biosynthesis method is more appropriate than the chemical method for producing the nanoparticles because it does not need any special facilities; it is also economically affordable. In the current study, the silver nanoparticles (AgNPs) were obtained by using a very simple and low‐cost method via Glaucium corniculatum (L.) Curtis plant extract. The characteristics of the AgNPs were investigated using techniques including: X‐ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy. The SEM and TEM images showed that the nanoparticles had a spherical shape, and the mean diameter of them was 53.7 and 45 nm, respectively. The results of the disc diffusion test used for measuring the anti‐bacterial activity of the synthesised nanoparticles indicated that the formed nanoparticles possessed a suitable anti‐bacterial activity. [ABSTRACT FROM AUTHOR]

Microalgae and Cyanobacteria extracts can be used for the synthesis of spherical silver nanoparticles by the reduction of AgNO 3 under air atmosphere at room temperature. Here, we synthesized AgNPs using extracts of one cyanobacterium (Synechococcus elongatus) and two microalgae (Stigeoclonium sp. and Cosmarium punctulatum). The nature of the AgNPs was characterized by TEM, HR-TEM, EDS, and UV–Vis. Considering the large quantity of functional groups in the ligands of AgNPs, we suppose they could retain ion metals, which would be useful for water decontamination. Thus, their capacity to adsorb iron and manganese at concentrations of 1.0, 5.0, and 10.0 mg L−1 in aqueous solutions was evaluated. All experiments were performed in triplicate of microorganism extract with no addition of AgNO 3 (control) and AgNP colloid (treatment) at room temperature. The ICP analyses showed that the treatments containing nanoparticles were commonly more efficient at removing Fe3+ and Mn2+ ions than the corresponding controls. Interestingly, the smaller nanoparticles (synthesized by Synechococcus elongatus) were the most effective at removing Fe3+ and Mn2+ ions, probably due to their higher surface area:volume ratio. The green synthesized AgNPs proved to be an interesting system for the manufacture of biofilters that could be used to capture contaminant metals in water. [Display omitted] • Cyanobacteria and algae do eco-friendly green synthesis of metal nanoparticles. • Different silver NPs were synthesized by different species. • Nanobiofilters for metals remotion are of interest for water treatment. • AgNPs biosynthesized by microalgae and cyanobacteria can remove metals from water. [ABSTRACT FROM AUTHOR]