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Nanoparticle synthesis under environmentally friendly conditions has been conducted utilizing natural resources in order to reduce the reliance on hazardous chemicals. For example, the utilization of microbial synthesis has enabled the production of nanoparticles that exhibit biocompatibility, stability, and safety. Microorganisms facilitate the growth of crystals while preventing aggregation. They serve as both reducing agents and capping agents by offering enzymes, peptides, poly(amino acids), polyhydroxyalkanoate, and polysaccharides. In this review, we present an overview of nanoparticle synthesis based on microorganisms including bacteria, fungi, algae, and actinobacteria, encompassing metals such as gold (Au), silver (Ag), platinum (Pt), palladium (Pd), copper (Cu), titanium dioxide ((TiO2), zinc oxide (ZnO), iron oxide (Fe2O3), and selenium (Se). The nanoparticles typically vary in size from 1 to 100 nm and exhibit various shapes including spherical, rod-shaped, triangular, cubic, and hexagonal shapes. Additionally, this review discusses the mechanisms behind the synthesis of metal nanoparticles by microorganisms, whether they occur intracellularly or extracellularly. [ABSTRACT FROM AUTHOR]

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, hydrogels were synthesized using Prunus persica ev. Bayramiç Beyazı extract as a crosslinker. N-3-(Dimethylamino)propyl methacrylamide (DMAPMA) and 2-Hydroxyethyl methacrylate (HEMA) monomers were used in hydrogels synthesized by redox polymerization. Hydrogel@Ag composites were created by synthesizing Ag0 nanoparticles within hydrogel network structures cross-linked with plant extract using an in-situ green synthesis method. These hydrogels and composites were characterized by swelling, FTIR, TEM, XRD, TGA methods. The synthesized hydrogels and hydrogel@Ag composites were loaded with Naproxen and Cefazolin drugs. The in-vitro drug release profiles of the hydrogels were examined in a pH = 5.5 and PBS environment, and it was determined that approximately 75% of the drugs were released within 5 h. The release kinetics model for the hydrogels was the Higuchi model, followed by the Korsmeyer-Peppas model. Ag0 nanoparticle encapsulation significantly affected the degree of swelling. The hydrogel cross-linked with MBA showed a swelling capacity of 370.16% by mass, while the hydrogel cross-linked with fruit extract exhibited a swelling capacity of 1000.78% by mass. The silver-encapsulated hydrogel demonstrated an even higher swelling capacity of 2313% by mass. Additionally, antibacterial tests against Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus faecalis microorganisms, showed that Ag-free hydrogels did not exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

This study is a further scale-up trial from the previously reported process optimization study on the green synthesis of silver nanoparticles (AgNPs) using Indonesian medicinal plant extracts. The present study utilized Phyllanthus niruri (PN) herb extracts, Orthosiphon stamineus (OS) leaf extracts, and Curcuma longa (CL) rhizome extracts as reducing agents to synthesize AgNPs on a larger scale. Upscaling increased the synthesis volume (from 100 mL to 1000 mL) and the centrifugation volume (from 1 mL to 40 mL) at various durations at 70°C for 60 min. The results showed that the minimum centrifugation duration to obtain optimal AgNPs was 5 minutes. The formation AgNPs were then characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), particle size and zeta potential analyzer, and X-ray diffractometer (XRD). The results showed the spherical silver nanoparticles with an average particle size (MI) of 169 nm (PN), 179.1 nm (OS), and 623 nm (CL), polydispersity index (PDI) value of 0.2202 (PN), 0.2579 (OS), and 0.00872 (CL) and the face-centered cubic (fcc) crystal structure. The green synthesis method using PN and OS extracts proved effective, environmentally friendly, safe, and cost-effective for the synthesis of AgNPs. The findings of this study have the potential to provide a green synthesis method for the production of AgNPs on a larger scale. [ABSTRACT FROM AUTHOR]

Wound healing is a crucial biological process for tissue repair and regeneration, preventing infections and complications. There's been a growing interest in exploring sustainable wound healing strategies in recent years. This review examines the use of green-synthesized silver nanoparticles (AgNPs) in sustainable wound healing strategies. It highlights the need for innovative approaches and the challenges posed by infections. The current wound therapies and treatments, highlighting gaps in existing methodologies, are evaluated. This review provides a comprehensive overview of the current state-of-the-art in green synthesis techniques for the synthesis of AgNPs. The properties and characterization of AgNPs are elucidated, providing insights into their efficacy. The biocompatibility of AgNPs in wound healing is also explored, emphasizing safety in medical applications. Green synthesized AgNPs incorporated wound dressings are detailed, showcasing their potential in clinical settings. Challenges and future perspectives are discussed, addressing hurdles to widespread implementation. The conclusion consolidates key findings, offering a synthesized perspective on the potential of green-synthesized AgNPs in revolutionizing current knowledge on innovative approaches for sustainable wound healing practices. [ABSTRACT FROM AUTHOR]

Introduction: Soybean is a rich source of bioactive components with good nutritional support and is easily available. In the treatment of cancer, green synthesis of silver nanoparticles (AgNPs) from plant-based samples has gained attentions due to its potency and feasibility. In the present study, using soybean extracts (GM), silver nanoparticles are synthesized and analyzed for their anticancer potency. Methods: The synthesized GM-AgNPs were characterized via UV-Vis spectroscopy, Fourier transform-infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) techniques for further analysis. Antibacterial activity was evaluated using the disc method and anti-hemolysis activity using the in vitro method, followed by anticancer property evaluation by cytotoxicity, cell migration, apoptosis, and cell cycle. Results and discussion: Our results showed that the synthesized GM-AgNPs were spiral-shaped with a size range of 5-50 nm. The antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae showed the maximum zone of inhibition at 250 ^ig/mL in comparison with gentamicin. On exploring the anti-hemolysis efficiency, at 200 pg/mL, GM-AgNPs showed no hemolysis in comparison to the extract which showed 40% hemolysis. On analysis of GM-AgNPs against the breast cancer cell line, the nanoparticles displayed the IC50 value of 74.04 pg/mL. Furthermore, at the IC50 concentration, cancer cell migration was reduced. The mechanism of action of GM-AgNPs confirmed the initiation of apoptosis and cell cycle arrest in the sub-G0/G1 (growth phase) phase by 48.19%. In gene expression and protein expression analyses, Bax and Bcl-2 were altered to those of normal physiology. [ABSTRACT FROM AUTHOR]

Re-designing existing nano-silver technologies to optimize efficacy and sustainability has a tangible impact on preventing infections and limiting the spread of pathogenic microorganisms. Advancements in manufacturing processes could lead to more cost-effective and scalable production methods, making nano-silver-based antimicrobial products more accessible in various applications, such as medical devices, textiles, and water purification systems. In this paper, we present a new, versatile, and eco-friendly one-pot process for preparing silver nanoparticles (AgNPs) at room temperature by using a quaternary ammonium salt of hydroxyethyl cellulose (HEC), a green ingredient, acting as a capping and reducing agent. The resulting nano-hybrid phase, AgHEC, consists of AgNPs embedded into a hydrogel matrix with a tunable viscosity depending on the conversion grade, from ions to nanoparticles, and on the pH. To investigate the synthesis kinetics, we monitored the reaction progress within the first 24 h by analyzing the obtained NPs in terms of particle size (dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM)), Z-potential (ELS), surface plasmon resonance (UV-VIS), crystallographic phase (XRD), viscosity, and reaction yield (inductively coupled plasma-optical emission spectrometry (ICP-OES)). To explore the design space associated with AgHEC synthesis, we prepared a set of sample variants by changing two independent key parameters that affect nucleation and growth steps, thereby impacting the physicochemical properties and the investigated antimicrobial activity. One of the identified design alternatives pointed out an improved antimicrobial activity in the suspension, which was confirmed after application as a coating on nonwoven cellulose fabrics. This enhancement was attributed to a lower particle size distribution and a positive synergistic effect with the HEC matrix. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles were synthesized via green synthesis using fenugreek (Trigonella foenum‐graecum L.) seeds of variety HM 425. The AgNPs were characterized by using UV‐Visible spectroscopy, Particle size analyzer, Field emission scanning electron microscopy coupled to Energy dispersive X‐ray spectroscopy, XRD, High resolution transmission electron microscopy and Fourier Transform Infrared Spectroscopy. The AgNPs were spherical and had an average particle size of 28 nm. The reduction of cationic dyes Methylene blue, Rhodamine B, and an anionic azo dye Methyl Orange by Sodium borohydride was used as a model reaction to investigate the catalytic ability of AgNPs. The results demonstrated an efficient catalytic dye degradation of methylene blue (95.81 %, 25 min, 0.1737±0.01 min−1), Rhodamine B (90.23 %, 15 min, 0.1388±0.01 min−1) and methyl orange (83.63 %, 39 min, 0.0412±0.002 min−1). The synthesized AgNPs had an excellent detection limit of 12.50 μM for Hg2+, making them excellent solid bio‐based sensors for mercury sensing. [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]

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 work, silver nanoparticles (AgNPs) were synthesized from cashew nutshell liquid (CNSL) by varying the concentration of silver ions and the pH of the CNSL extract. The synthesized AgNPs were further characterized to study their surface, structural, and morphological properties and tested for the removal of methylene blue (MB) dye. The results of this study showed that depending on the conditions, particles of various sizes, ranging from 1 to 60 nm, and different degrees of stabilization and agglomeration were produced. The concentration of silver ions equal to 3 mM and the pH of the extract of ~4.5 (AgNP3) resulted in the most efficient synthesis, where particles appeared to be highly stabilized and homogeneously distributed on the surface, exhibiting a small average particle size and a narrow particle size distribution (6.7 ± 6.5 nm). Such particles further showed the highest percent removal of MB, where up to 80% removal was recorded within the first 20 min. Higher concentrations of silver ions and higher pH of the extract resulted in substantial particle agglomeration and particles being over-capped by the CNSL biomolecules, respectively, which further negatively affected the ability of particles to remove MB. Finally, the fact that visible light showed no significant effect on the removal of MB, with the average removal rates found to be about the same as in the dark, suggests the strong catalytic nature of AgNPs, which facilitates the electron transfer reactions leading to MB reduction. [ABSTRACT FROM AUTHOR]

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]

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]

Green silver nanoparticle-based spectrophotometric and spectrofluorimetric measurements for tioguanine (TG) determination are reported in this study as a reliable, non-toxic approach with a sensitive and effective green assembly. TG is an anti-cancer medication used to treat leukemia. Chemical-based method development for its analysis purpose may have a dangerous effect on the environment. Cleaner, more affordable methods have received a lot of attention lately. By using Box–Behnken design under a response surface approach, the factors essential for the synthesis of green silver nanoparticles were optimized. For the two approaches, experimental optimization resulted in linear dynamic ranges of 55–220 and 65–200 nM, respectively. The technique was sensitive enough to detect and quantify TG at concentrations of 6.6 and 12.4 nM, respectively. The devised method is validated by satisfactory findings for the statistical treatment of the analytical data in accordance with the ICH requirements. Green nanoparticle formation was supported by X-ray diffraction analysis, scanning electron microscopy, and infrared spectroscopy analysis. When the developed nanosensors were used with the formulations, the relative standard deviation achieved was less than 2%. The photocatalytic degradation of acid fuchsin dye produced results that demonstrated the possible application of the developed nanosensors. [ABSTRACT FROM AUTHOR]

Herein, a study on the chitosan-amalgamated gold nanoparticles (AuNPs)- and silver nanoparticles (AgNPs)-based molecularly imprinted polymer (MIP) film and its application to recognize/remove ciprofloxacin (CIP) antibiotic in real samples is reported. The pomegranate peel at pH 8 is used for the reduction of silver nitrate solution to form AgNPs, whereas chitosan itself is used for the reduction of gold chloride solution to form AuNPs. The size of the synthesized AgNPs and AuNPs is in the range 30–45 and 45–50 nm, respectively, which is determined by dynamic light scattering (DLS). Further, the synthesized nanoparticles (NPs) are used to prepare MIP film. The molecularly tailored chitosan-based nanocomposite is used as a functional biopolymer to enhance the adsorption capacity and surface area of MIP film. The properties of synthesized chitosan-based AuNPs- and chitosan-based AgNPs-MIP composite (Chi@AuMIP and Chi@AgMIP) exhibited much higher adsorption capacity than non-imprinted polymer (NIP). The results revealed that the theoretical equilibrium constant (KL) and maximum adsorption capacity (Qmax) found by the Langmuir model are 12.2 and 20.48 mg g−1 for Chi@AuMIP and 18.31 and 34.13 mg g−1 for Chi@AgMIP, respectively. The recovery percentage of CIP for Chi@AuMIP and Chi@AgMIP is 98 and 80%, respectively. The selectivity experiment data suggest maximum adsorption capacity for targeted molecule (CIP) by the MIP as compared to analogs of template molecule. MIP showed relative potential selectivity and good recovery percentage for CIP in real samples as well. [ABSTRACT FROM AUTHOR]

Hydrotalcite–silver (HT−Ag) nanoparticles have been involved in various daily crucial applications, such as antibacterial, photocatalytic, adsorption, etc. There are many approaches to synthesizing silver nanoparticles (AgNPs) decorated on hydrotalcite (HT) surface and the most used approach is using a strong reducing agent. Thus, affordable but effective "green" reducing agents – Syzygium nervosum leaf extract, are taken into account in this work to solve several issues related to chemical reducing agents. This work aimed to assess the effect of Syzygium nervosum leaf extract as a reducing agent for green synthesis of AgNPs on HT through an optimizing process using response surface methodology (RSM) and the Box‐Benken model. The optimal conditions for the synthesis of AgNPs on HT include a reaction time of 6.15 hours, a reaction temperature of 50 °C, and the ratio of diluted Syzygium nervosum leaf extract to reduce AgNO3 of 50.37 mL/mg. Under the optimal conditions, the yield of the reduction reaction reached 77.54 %, close to the theoretical value of 76.97 %. The optimization model was suitable for the experiment data. Besides, the morphology, density, and characteristics of AgNPs on the surface of HT layers have been determined by using Ultraviolet‐visible spectroscopy, Field emission scanning electron microscopy (FESEM), High‐resolution transmission electron microscopy (HR‐TEM), selected area diffraction, X‐ray diffraction, Dynamic light scattering (DLS), Infrared (IR) spectroscopy, Fluorescence emission spectroscopy (FE), Brunauer‐Emmett‐Teller (BET) methods. The spherical AgNPs were synthesized successfully on the surface of HT with the average particle size of 13.0±1.1 nm. Interestingly, HT−Ag hybrid materials can inhibit strongly the growth of E. coli, S. aureus as well as two antibiotic resistance bacterial strains, P. stutzeri B27, and antibiotic resistance E. coli. Especially, the antibacterial activity quantification and durability of the HT−Ag hybrid materials were also tested. Overall, the HT−Ag hybrid materials are very promising for application in material science and biomedicine fields. [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]

The ability to generate valuable products through oxidation makes it one of the most pivotal industrial processes. While organic oxidants have traditionally been the focus in converting alcohols into carbonyl compounds, inorganic oxidants have been relatively underutilized. In this study, we delve into the influence of Potassium periodate (KIO4) in an acidic environment on the oxidation of selected alcohols, comparing its performance with that of catalyst silver nanoparticles prepared from two distinct plant sources: Madhuca longifolia flowers and Ziziphus jujuba leaves. The reactions were intentionally conducted under conditions that adhere to first-order kinetics. At regular intervals throughout the reaction, iodometric measurements were employed to monitor the progress of the reaction. It was noted that the oxidation rate exhibited a proportional increase corresponding to the concentration of alcohol for all the alcohols examined, while it decreased with an increasing concentration of the oxidant. In contrast, when AgNP catalysts were employed in conjunction with KIO4, significantly higher rate constants were achieved compared to using KIO4 alone. This research underscores the potential of silver nanoparticles prepared from plant sources as effective catalysts for alcohol oxidation, offering promising avenues for the development of more efficient and sustainable oxidation processes in the industry. [ABSTRACT FROM AUTHOR]

A sustainable method for producing silver nanoparticles (AgNPs) using Vitis vinifera seed extract has been proposed. The formation of AgNPs was confirmed through spectroscopy, X-ray Diffraction (XRD), and electron microscopy. The UV-visible spectrophotometer revealed distinct absorbance peaks at 398.80 nm and 416.24 nm, signifying the presence of Surface Plasmon Resonance (SPR). XRD, quasi-elastic light scattering, and surface topography results exposed that the AgNPs were crystalline and had rod-like shapes. FTIR identified seed extract functional groups that reduced silver ions to AgNPs and acted as capping agents. The nanoparticles showed inhibition against gram-positive microorganisms like Staphylococcus pneumonia and Mycobacterium tuberculosis, surpassing their effectiveness against gram-negative microorganisms such as Pseudomonas fluorescens. This environmentally responsible approach not only offers a green synthesis method but also holds promise for combating specific pathogenic bacteria. [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]

In this work, the hexane, chloroform, and methanol extracts from Kalanchoe fedtschenkoi were utilized to green-synthesize silver nanoparticles (Kf1-, Kf2-, and Kf3-AgNPs). The Kf1-, Kf2-, and Kf3-AgNPs were characterized by spectroscopy and microscopy techniques. The antibacterial activity of AgNPs was studied against bacteria strains, utilizing the microdilution assay. The DPPH and H2O2 assays were considered to assess the antioxidant activity of AgNPs. The results revealed that Kf1-, Kf2-, and Kf3-AgNPs exhibit an average diameter of 39.9, 111, and 42 nm, respectively. The calculated ζ-potential of Kf1-, Kf2-, and Kf3-AgNPs were −20.5, −10.6, and −7.9 mV, respectively. The UV-vis analysis of the three samples demonstrated characteristic absorption bands within the range of 350–450 nm, which confirmed the formation of AgNPs. The FTIR analysis of AgNPs exhibited a series of bands from 3500 to 750 cm−1, related to the presence of extracts on their surfaces. SEM observations unveiled that Kf1- and Kf2-AgNPs adopted structural arrangements related to nano-popcorns and nanoflowers, whereas Kf3-AgNPs were spherical in shape. It was determined that treatment with Kf1-, Kf2-, and Kf3-AgNPs was demonstrated to inhibit the growth of E. coli, S. aureus, and P. aeruginosa in a dose-dependent manner (50–300 μg/mL). Within the same range, treatment with Kf1-, Kf2-, and Kf3-AgNPs decreased the generation of DPPH (IC50 57.02–2.09 μg/mL) and H2O2 (IC50 3.15–3.45 μg/mL) radicals. This study highlights the importance of using inorganic nanomaterials to improve the biological performance of plant extracts as an efficient nanotechnological approach. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles was carried out using leaf extract from Calluna vulgaris. The formation of nanoparticles was confirmed through the emergence of a surface plasmon resonance band in ultraviolet-visible spectroscopy. The characterization conducted using various microscopic techniques revealed that the nanoparticles mostly ranged in size from approximately 20 to 70 nm. Analysis, including Fourier transform infrared spectrometry, X-ray diffraction, and energy-dispersive X-ray spectroscopy, confirmed the chemical, crystalline structure, and presence of silver, respectively. The synthesized nanoparticles exhibited notable stability with an average zeta potential of -23.1 ± 0.6 mV. Evaluation of their antibacterial activity against Staphylococcus aureus and Escherichia coli demonstrated significant efficacy with diameters of inhibition zones measuring 10.23 ± 0.54 mm and 15.38 ± 0.32 mm, respectively. Additionally, the nanoparticles displayed a remarkable inhibition of approximately 88% against E. coli biofilm formation at a concentration of 100 µg/mL. They also exhibited unique photocatalytic performances. This research contributes to the literature in this field by producing new silver nanoparticles with cost-effectiveness, stability, antibacterial, antioxidant, antibiofilm, and photocatalytic properties, while using a previously untapped plant extract for this purpose. [ABSTRACT FROM AUTHOR]

Traditional methods of pest control are not able to prevent crop damage due to devastating pests. Therefore, through nanobiotechnology nano-bio pesticides and conjugated nanoparticles are produced as a pest control agent. The present work focused on the synthesis, characterization of silver nanoparticles (AgNPs) using Ocimum tenuiflorum leave extract and its larvicidal activity against Helicoverpa armigera. AgNPs were characterized by UV–Vis spectral analysis, indicated an absorbance of 4.695 at 560 nm. Moreover, Scanning Electron Microscope and X-ray Powder Diffraction showed that particles were spherical, ranging from 10 nm to 65 nm. The larvae of H. armigera were provided with an artificial diet with AgNPs coating of 0.25%, 0.5%, 0.75%, and 100% pure concentration. After 24 h, a dose response relationship in mortality was found maximum in pure AgNPs treated group, 83.33% and 75% in 0.75% treated group and 0.5% treated group, respectively. While the least mortality of 50% was observed in the 0.25%, AgNPs treated group. The LC50 calculated was 20.33 µL for AgNPs. It can be concluded that silver-nanoparticles possess a larvicidal effect. Furthermore, the biosynthesis of these particles is an efficient and profitable approach. [ABSTRACT FROM AUTHOR]

Cryptosporidium parvum (C. parvum) is one of the most prevalent species infecting humans and animals. Currently, the only FDA-licensed drug to treat cryptosporidiosis is nitazoxanide (NTZ), with no efficacy in immunocompromised hosts. Citrus paradisi (C. paradisi) has demonstrated anti-protozoal activities. This study aimed to investigate the anti-cryptosporidiosis effect of C. paradisi peel extract, either alone or in mediating the green synthesis of chitosan silver nanoparticles (Cs/Ag NPs), compared to NTZ. Mice were sorted into nine different groups. The effectiveness of the treatments was evaluated using parasitology, histopathology, immunohistochemistry, and immunology. C. paradisi outperformed nitazoxanide regarding oocyst shedding (79% vs. 61%). The effectiveness of NTZ Cs/Ag NPs and Citrus Cs/Ag NPs was enhanced to 78% and 91%, respectively. The highest oocyst inhibition was obtained by combining NTZ and Citrus Cs/Ag NPs (96%). NF-κB, TNF-α, and Il-10 levels increased in response to infection and decreased in response to various treatments, with the highest reduction in the group treated with combined NTZ citrus Cs/Ag NPs. Combining C. paradisi with NTZ could have a synergistic effect, making it a potentially effective anti-cryptosporidiosis agent. Utilizing C. paradisi in the green synthesis of Cs/Ag NPs improves the therapeutic response and can be used to produce novel therapeutic antiparasitic drugs. [ABSTRACT FROM AUTHOR]

Hafnia sp. was one of the specific spoilage bacteria in aquatic products, and the aim of the study was to investigate the inhibition ability of the silver nanoparticles (AgNPs) biosynthesis by an aqueous extract of Prunus persica leaves toward the spoilage-related virulence factors of Hafnia sp. The synthesized P-AgNPs were spherical, with a mean particle size of 36.3 nm and zeta potential of 21.8 ± 1.33 mV. In addition, the inhibition effects of P-AgNPs on the growth of two Hafnia sp. strains and their quorum sensing regulated virulence factors, such as the formation of biofilm, secretion of N -acetyl-homoserine lactone (AHLs), proteases, and exopolysaccharides, as well as their swarming and swimming motilities were evaluated. P-AgNPs had a minimum inhibitory concentration (MIC) of 64 μg ml−1 against the two Hafnia sp. strains. When the concentration of P-AgNPs was below MIC, it could inhibit the formation of biofilms by Hafnia sp at 8–32 μg ml−1, but it promoted the formation of biofilms by Hafnia sp at 0.5–4 μg ml−1. P-AgNPs exhibited diverse inhibiting effects on AHLs and protease production, swimming, and swarming motilities at various concentrations. [ABSTRACT FROM AUTHOR]

In this work, AgNPs were synthesized using an anthocyanin extract from Peruvian purple potato INIA 328—Kulli papa. The anthocyanin extract was obtained through a conventional extraction with acidified ethanolic aqueous solvent. This extract acted as both a reducing and stabilizing agent for the reduction of silver ions. Optimization of synthesis parameters, including pH, reaction time, and silver nitrate (AgNO3) concentration, led to the optimal formation of AgNPs at pH 10, with a reaction time of 30 min and an AgNO3 concentration of 5 mM. Characterization techniques such as X-ray diffraction (XRD) and dynamic light scattering (DLS) revealed that the AgNPs had a crystallite size of 9.42 nm and a hydrodynamic diameter of 21.6 nm, with a zeta potential of −42.03 mV, indicating favorable colloidal stability. Fourier Transform Infrared (FTIR) analysis confirmed the presence of anthocyanin functional groups on the surface of the AgNPs, contributing to their stability. Furthermore, the bacterial activity of the AgNPs was evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). For E. coli, the MIC was 0.5 mM (0.05 mg/mL) and the MBC was 4.5 mM (0.49 mg/mL). Similarly, for S. aureus, the MIC was 0.5 mM (0.05 mg/mL) and the MBC was 4.0 mM (0.43 mg/mL). These results highlight the potential benefits of AgNPs synthesized from Peruvian purple potato anthocyanin extract, both in biomedical and environmental contexts. [ABSTRACT FROM AUTHOR]

Simple Summary: Citrus production worldwide is threatened by the bacterium Liberibacter spp. Fagen and its vector Diaphorina citri Kuwayama. In the absence of an effective method against the bacteria, management plans are directed towards the vector. However, management strategies such as chemical control have presented difficulties in controlling the insect. Therefore, the application of new control techniques, such as nanoparticles by green synthesis, emerges as a promising control alternative. To address this issue, the objective of this study was to evaluate silver nanoparticles by green synthesis against D. citri nymphs in the laboratory and greenhouse. The results show that the nanoparticles achieved up to 100% mortality in the laboratory and 80% in the greenhouse. These results demonstrate the effectiveness of silver nanoparticles as a potential control method for the insect. Diaphorina citri Kuwayama (Hemiptera: Liviidae) is a vector of Liberibacter asiaticus Jagoueix et al. and Liberibacter americanus Teixeira et al., causal agents of the critical yellow dragon disease or Huanglongbing (HLB), which affects citrus production worldwide. Recently, green synthetic nanoparticles have emerged as a potential alternative to control of agricultural insect pests. The insecticide effect of silver nanoparticles (AgNPs) on 2nd instar nymphs of D. citri under laboratory and greenhouse conditions was evaluated. Mortality was recorded 24, 48, and 72 h after application on D. citri nymphs under both laboratory and greenhouse conditions. The laboratory results showed that AgNPs caused 97.84 and 100% mortality at 32 and 64 ppm, respectively, 72 h after treatment. In the greenhouse, AgNPs caused 78.69 and 80.14% mortality using 64 and 128 ppm 72 h after application. This research is the first to evaluate the green synthesis AgNPs on D. citri and are a promising strategy to control the pest. [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]

Silver nanoparticles (AgNPs) can be produced safely and greenly using water hyacinth, an invasive aquatic plant, as a reducing agent. This study aimed to optimize the UV-irradiation parameters for the synthesis of AgNPs from water hyacinth leaf extract. The study varied the reaction time and pH levels and added a stabilizing agent to the mixture. The synthesized AgNPs were characterized using UV-visible spectroscopy (UV-vis), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma optical emission spectroscopy (ICP-OES). The findings revealed that the optimal conditions for synthesizing AgNPs were achieved by adjusting the pH level to 8.5, adding starch as a stabilizing agent, and exposing the mixture to UV-A radiation for one hour. These conditions resulted in the smallest size and highest quantity of AgNPs. Furthermore, the synthesized AgNP colloids remained stable for up to six months. This study highlights the potential of utilizing water hyacinth as a sustainable and cost-effective reducing agent for AgNP synthesis, with potential applications in pharmaceuticals, drug development, catalysis, and sensing detection. [ABSTRACT FROM AUTHOR]

Electrospinning has garnered much attention for skin renewal, emphasizing skin's pivotal role as a primary protective layer and the susceptibility to loss caused by burns. The research aimed to develop a multipurpose wound dressing that safeguard injuries and facilitates the renewal of dermal tissues. Two-layer nanofibers were prepared using polyvinyl alcohol–chitosan–gelatin/polyacrylonitrile (PVA–CS–Gel/PAN), containing mupirocin (Mu 3% w/w) in underlying layer and silver nanoparticles (AgNps) in the upper layer with varying concentrations. AgNps were synthesized from Capsella bursa-pastoris extract by the green method and characterized using XRD, SEM, FTIR, and UV techniques. Then, PVA–CS–Gel/PAN solutions with AgNps and Mu were electrospun into multilayer dressings. The effectiveness of the nanofibers was evaluated through in vitro and in vivo tests. The study examined the nanofibers containing spherical AgNps with an average diameter of 72.57 nm and a negative surface charge (− 12 mv). They had uniform and smooth surfaces with a diameter range of 476.31 to 926.04 nm. According to swelling and contact angle results, hydrophilicity of samples had a direct relation with water absorption. Controlled drug release within 72 h followed Higuchi or first-order profiles. MTT and antibacterial analyses indicated that optimized nanofibers (Mu/1% AgNps) had suitable biocompatibility and synergistic potential against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. Additionally, an in vivo test on rats with second-degree burns after 28 days demonstrated a 98.97% improvement in revival, outperforming its commercial counterparts. Consequently, the results position the designed composite nanofiber as a promising candidate for wound healing applications, aiding in enhancing skin regeneration. [ABSTRACT FROM AUTHOR]

Nonwoven fabrics are the primary source of disposable medical clothing, which cause a huge medical waste. One possible way to reuse this disposable clothing is through antibacterial treatment. Among various metal nanoparticles, silver nanoparticles (AgNPs) are preferable regarding ecology and human health. Green synthesis is an ecological alternative to synthesize AgNPs from silver nitrate (AgNO3) solution. The silver nanoparticles (AgNPs) were successfully synthesized from Calendula arvensis extract and AgNO3 at a certain temperature and incorporated into the fabric by padding and in-situ method. The pretreatments applied to the nonwoven fabric were found very important in terms of providing antibacterial activity. AgNPs applied according to the in situ method could provide 99% antibacterial activity on nonwoven surface fabrics. The samples treated by AgNPs with the in situ method performed better for both particle filtration efficiency (PFE) and bacterial filtration efficiency (BFE) than the samples treated with the padding method. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) have gained significant attention due to their multifunctional properties and broad applications in various fields. In this study, we present a novel and sustainable approach for the synthesis of silver nanoparticles (AgNPs) using waste materials, dried banana pith extract (BPE) and rice water. The synthesised AgNPs exhibit a size of 43 nm and zeta potential of −24.1 mV. A maximum temperature rise of 4°C with an efficiency of 41% is achieved within a short time by the photothermal activity. The qualitative colorimetric detection of Fe3+ and its quantitative spectroscopic detection are achieved in a linear detection range of 20–80 μM and with a limit of detection of 8.5 μM. The sensing mechanism is explained in terms of cooperative binding of Fe3+ ions to BPE-AgNPs. A homogeneous, flexible and stable AgNP-rice starch gel is formed. The work offers environmentally conscious nanomaterials for diverse applications. [ABSTRACT FROM AUTHOR]

The adoption of green chemistry protocols in nanoparticle (NP) synthesis has exhibited substantial potential and is presently a central focus in research for generating versatile NPs applicable across a broad spectrum of applications. In this scientific contribution, we, for the first time, examined the ability of Aconitum Laeve (A. Laeve) crude extract to synthesize silver and gold nanoparticles (AgNPs@AL; AuNP@AL) and explored their potential applications in biological activities and the catalytic degradation of environmental pollutants. The synthesized NPs exhibited a distinctive surface plasmon resonance pattern, a spherical morphology with approximate sizes of 5–10 nm (TEM imaging), a crystalline architecture (XRD analysis), and potential functional groups identified by FTIR spectroscopy. The antibacterial activity was demonstrated by inhibition zones that measured 16 and 14 mm for the AgNPs@AL and AuNP@AL at a concentration of 80 µg/mL against Staphylococcus aureus and 14 and 12 mm against Escherichia coli, respectively. The antioxidant potential of the synthesized NPs was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-Oxide (PTIO), and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Our findings suggest that the AuNP@AL effectively countered the tested radicals considerably, displaying IC50 values of 115.9, 103.54, and 180.85 µg/mL against DPPH, PTIO, and ABTS, respectively. In contrast, the AgNPs@AL showed IC50 values of 144.9, 116.36, and 95.39 µg/mL against the respective radicals. In addition, both the NPs presented significant effectiveness in the photocatalytic degradation of methylene blue and rhodamine B. The overall observations indicate that A. Laeve possesses a robust capability to synthesize spherical nanoparticles, exhibiting excellent dispersion and showcasing potential applications in both biological activities and environmental remediation. [ABSTRACT FROM AUTHOR]

A comparative study was applied to investigate the potential of Callistemon citrinus (bottlebrush) flower extract (BBE) and Punica granatum (pomegranate) peel extracts (PPE) for the sustainable synthesis of the silver nanoparticles, Ag-BBE and Ag-PPE, respectively. The synthesis process of Ag NPs using the selected extracts was applied under optimized conditions. Hence, the effect of the selected plant's type on the different characteristics of the synthesized green Ag NPs was investigated. The UV-Vis spectroscopy revealed the presence of the characteristic silver peaks at 419 and 433 nm of the Ag-BBE and Ag-PPE, respectively. The XRD spectra reported the fcc phase formation of Ag NPs. The TEM results highlighted the morphological features of the synthesized Ag NPs. with a size range of 20–70 nm, and with 10–30 nm for Ag-BBE and Ag-PPE, correspondingly. The Raman spectra revealed characteristic silver bands in the Ag-PPE and reflected some bands related to the natural extract in the Ag-BBE sample. The antimicrobial activity and statistical analysis investigation were conducted against four selected oral pathogens (Staphylococcus aureus (SA), Candida albicans (CA), Staphylococcus epidermidis (S. epi), and Enterococcus faecalis (EF)). Both tested extracts, BBE, and PPE, revealed potential effectivity as reducing and capping agents for Ag NP green synthesis. However, the synthesized NPs demonstrated different features, depending on the used extract, reflecting the influence of the plant's biomolecules on the nanoparticles' properties. [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]

Microorganisms (MOs) are prominent in ecological functioning and balance. The rhizosphere is considered one of the most diverse ecosystems on Earth and serves as a breeding spot for many MOs. Rhizosphere microbial diversity changes according to plant species, genotype, and the nature of the soil. The current study reports the possible use of bacteria isolated from the rhizosphere of Azadirachta indica for synthesizing silver nanoparticles (AgNPs). The physicochemical characterization and antibacterial activity of these green synthesized AgNPs are also reported. The gene (16S rRNA) sequence of bacteria isolated from the rhizosphere showed a maximum similarity of 99.25% with Bacillus subtilis. After incubation, the colorless reaction mixture transformed to brown, which indicates the formation of AgNPs, and UV-vis spectral analysis also confirmed the biosynthesis of AgNPs. Compared to lower temperatures, the efficiency of AgNP synthesis was high at the higher temperature. The scanning electron microscope image demonstrated spherical-shaped AgNPs with sizes ranging from 18 to 21 nm. Energy-dispersive X-ray analysis established the elemental analysis of synthesized AgNPs. The synthesized AgNPs showed strong bactericidal properties against pathogenic bacteria Klebsiella pneumonia, Pseudomonas aeruginosa, Escherichia coli, and methicillin-resistant Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Herein, a convenient and environment-friendly reduction strategy was employed to attach silver nanoparticles onto ceria nanorods (AgCe). Nanorods were synthesised through a green chemistry approach with varied silver contents and Citrus maxima peel extract as a reducing agent. The resulting AgCe nanocomposites were evaluated for their efficacy in reducing methyl orange (MO) at ambient temperature by employing NaBH4 as a protonating agent. The as-prepared samples were characterised by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray energy-dispersive spectroscopy, Raman spectroscopy, Brunauer–Emmett–Teller method, and high-resolution transmission electron microscopy. The as-prepared sample exhibited outstanding activity on the catalytic reduction of MO, and the synergistic effect between Ag nanoparticles and CeO2 nanorods was proved. Silver nanoparticles were formed and dispersed well on the surface of ceria nanorods. Based on the UV–Vis results, the activity of the samples with silver was superior to that of pure ceria. The 0.2AgCe sample was the most effective when the catalyst concentration was 0.08 g/L, and the molar ratio between MO and NaBH4 was 1/200. The entire catalytic reduction was thought to follow pseudo-first-order kinetics. Hence, Ag nanoparticles decorated on CeO2 efficiently offered excellent catalytic efficiency and stability in MO reduction and that the catalyst was suitable for practical applications, such as wastewater treatment. [ABSTRACT FROM AUTHOR]

AbstractFor the first time, methanolic leaf extract of the hydrophyte Persicaria senegalensis L. was evaluated for its ability to silver nanoparticles (AgNPs) biosynthesis. The effect of stirring time and plant extract concentrations was studied. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used for characterization of AgNPs. XRD confirmed the AgNPs formation with crystallite size in the range 23–71 nm. The crystallite size increased with increasing both stirring time and plant extract concentration. Antioxidants, including secondary metabolites such as flavonoids and phenols are substances that inhibit oxidative damage to the cell organisms by scavenging the free radicals and thus reducing the hazard of diseases. The scavenging and antioxidant activities of the plant leaf extract and AgNPs were evaluated and exhibited potent antioxidant activity. The total antioxidant capacity (TAC) of plant leaf extract and AgNPs was 52.41 and 10.13 µg AA equivalent/mg DW, respectively. Total phenolics (TPs) and total flavonoids (TFs), revealed high contents equal to 154.83 µg gallic acid equivalent and 100.05 µg quercetin equivalent/mg DW plant extract, respectively. [ABSTRACT FROM AUTHOR]

This work aims to analyze the influence of selected plants on the synthesis of silver nanoparticles (AgNPs). Six plants were chosen for the experiment, from which extracts were prepared: maclura fruit, spruce and ginkgo needles, green algae (Ch. kessleri), and mushrooms, namely Collybia nuda, and Macrolepiota procera. The composition of the extracts and colloids after preparation of the nanoparticles was analyzed using FTIR analysis. The composition of the extracts affected not only the rate of the synthesis but also the shape of the nanoparticles. TEM analysis confirmed the synthesis of mainly spherical nanoparticles (size range: 10–25 nm). However, triangular prisms and polyhedral nanoparticles synthesized by the extracts containing mainly flavonoids, terpenes, and phenols (the main compounds of resins) were also confirmed. EDS analysis was used to analyze the composition of the nanoparticles. It was proven that by choosing the right plant extract and using the appropriate technology with extract treatment, it is possible to prepare nanoparticles of different shapes. [ABSTRACT FROM AUTHOR]

Metal nanoparticle synthesis via environmentally friendly methods is gaining interest for their potential advantages over conventional physico-chemical approaches. Herein, we propose a robust green synthesis route for lignin-modified silver nanoparticles, utilizing the recovery of lignin as a renewable raw material and exploring its application in valuable areas. Through a systematic approach combining UV-Vis spectroscopy with AAS and DLS, we identified repeatable and scalable reaction conditions in an aqueous solution at pH 11 for homogeneous silver nanoparticles with high uniformity. The TEM median sizes ranged from 12 to 15 nm with circularity between 0.985 and 0.993. The silver nanoparticles yield exceeded 0.010 mol L−1, comparable with traditional physico-chemical methods, with a minimal loss of silver precursor ranging between 0.5 and 3.9%. Characterization by XRD and XPS revealed the presence of Ag-O bonding involving lignin functional groups on the pure face-centered cubic structure of metallic silver. Moreover, the lignin-modified silver nanoparticles generated a localized thermal effect upon near-infrared laser irradiation (808 nm), potentially allowing for targeted applications in the biomedical field. Our study showcases the potential of lignin as a renewable reducing and capping agent for silver nanoparticle synthesis, addressing some shortcomings of green synthesis approaches and contributing to the development of suitable nanomaterials. [ABSTRACT FROM AUTHOR]

• Green synthesis of agnps from H. tiliaceus L. leaves extract. • Characterization of agnps was done by FE-SEM, HR-TEM, XRD and FT-IR. • Nanoparticles were stable in charge, crystalline in shape, with an average size of 88.10 nm in colloidal form. • AgNPs displayed potential antioxidant activity and broad range of antibacterial activity. • AgNPs have been shown to have potential as a catalyst in the dye degradation process. The present study reports the green synthesis of silver nanoparticles (AgNPs) from aqueous extract of Hibiscus tiliaceus L. leaves and their application in dye degradation, antioxidant, antimicrobial, and anticancer activities. Analysis using Fourier transform infrared (FT-IR) spectroscopy revealed that plant metabolite functional groups had a role in the reduction and stability of AgNPs, and X-ray crystallography (XRD) demonstrated that the AgNPs were in crystal form. The UV–vis spectroscopy, dynamic light scattering (DLS), and zeta potential investigations revealed that the AgNPs were formed with an average size of 88.10 nm in colloidal form and were stable (-49 mV). The field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) confirmed the shape and size of the AgNPs as spherical with a particle size of 30 - 35 nm, respectively. The AgNPs exhibited potential antioxidant activity by total antioxidant, DPPH, and reducing power assays. The biosynthesized AgNPs displayed a wide range of antibacterial activity on Gram-ve and Gram+ve bacteria by the zone of inhibition assay. AgNPs showed good anticancer activity on MCF-7 cells with an IC 50 value of 65.83 µg/mL. Furthermore, AgNPs acted as potential catalysts in combination with the reducing agent sodium borohydride (NaBH 4) for the degradation of methylene blue (MB), methylene orange (MO), and methylene green (MG) dyes. The degradation efficiency of catalyst AgNPs in the attendance of NaBH 4 for 15 min was noted to be 12.8 %, 26.92 %, and 47.56 % for MO, MB, and MG, respectively. The study concluded that green synthesized AgNPs could be highly applicable as an antioxidant, antimicrobial, and anticancer agents in the biomedical field. Furthermore, AgNPs could be helpful in the remediation of dye effluents. [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]

Synthesis of silver nanoparticles with antibacterial properties using a one-pot green approach that harnesses the natural reducing and capping properties of cinnamon (Cinnamomum verum) bark extract is presented in this work. Silver nitrate was the sole chemical reagent employed in this process, acting as the precursor salt. Gas Chromatography-Mass Spectroscopy (GC-MS), High-Performance Liquid Chromatography (HPLC) analysis, and some phytochemical tests demonstrated that cinnamaldehyde is the main component in the cinnamon bark extract. The resulting bio-reduced silver nanoparticles underwent comprehensive characterization by Ultraviolet–Vis (UV-Vis) and Fourier Transform InfraRed spectrophotometry (FTIR), Dynamic Light Scattering (DLS), Transmission Electron Microscopy, and Scanning Electron Microscopy suggesting that cinnamaldehyde was chemically oxidated to produce silver nanoparticles. These cinnamon-extract-based silver nanoparticles (AgNPs-cinnamon) displayed diverse morphologies ranging from spherical to prismatic shapes, with sizes spanning between 2.94 and 65.1 nm. Subsequently, the antibacterial efficacy of these nanoparticles was investigated against Klebsiella, E. Coli, Pseudomonas, Staphylococcus aureus, and Acinetobacter strains. The results suggest the promising potential of silver nanoparticles obtained (AgNPs-cinnamon) as antimicrobial agents, offering a new avenue in the fight against bacterial infections. [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]

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]

Nanobiotechnology has achieved great advances in the field of scientific research in past years. Nanoparticles (NPs) with diameters ranging from 1 to 100 nm are the focus of nanotechnology. Green synthesis of encapsulated silver nanoparticles (eAgNPs) was carried out by using Solidago virgaurea L. (SvL) and Tussilago farfara L. (TfL) extract as reducing/protecting agent. An UV–vis spectrophotometer was used to determine the optimal conditions to produce eAgNPs from plant extracts, including pH, temperature, plant extract, and mixing times. The optimal conditions for AgNPs synthesis from the SvL plant and TfL plant were (1:1) extract-AgNO3, 24 h mixing time, and a temperature of 25 °C. SEM, TEM, FTIR, and UV–Vis Spectrophotometer analyses were carried out to ascertain the surface characterization and structural properties of eAgNPs and the nanofibrous mats' physicochemical characteristics. The results of the analysis revealed that the eAgNPs are nanosized and contain silver. eAgNPs-doped nanofiber production from polylactide acid (PLA) polymer was realized by electrospin method. The required production parameters for the electrospinning method of producing PLA-based nanofibers were investigated. Nanofiber was produced by combining 0.5 and 1% AgNPs in an 8% PLA solution. The biological effects of the developed PLA@eAgNPs nanofibrous mats were examined in vitro. The antibacterial activity of nanofibers against E. coli was determined using the agar diffusion method. eAgNPs and PLA-based nanostructured materials are suggested as bioactive coatings capable of preventing the development of microbial population on surfaces relevant to healthcare. [ABSTRACT FROM AUTHOR]

The presence of fixed orthodontic appliance favours the plaque accumulation and a compromise in oral hygiene. There are various methods in practice to minimize the white spot lesions (WSL) incidence, but which depend on the patients' compliance. It is prudent to introduce materials and methods which rely less on patient. The purpose of our study is to introduce a new silver nanoparticle (AgNPs) coating onto elastomeric ligatures and to assess its antimicrobial property and durability of the silver nanoparticles coating on the elastomeric ring. Out of a total sample of 69 clear elastomeric ligatures, 44 of them are equally allocated (n=22) to each of the two groups, Group A-test group (AgNPs coated) and Group-B-control (Non coated) for antimicrobial testing and rest for durability testing. The test group elastomeric modules coated with AgNPs were prepared from Agaricus bisporus extract and silver nitrate solution and tested for antimicrobial testing against Streptococcus mutans. Remaining test sample was utilised for determination of silver ion release(mg/L) when coated elastomeric rings are placed in artificial saliva and analyzed after T1 - 24 hours, T2 - 48 hours, T3 - 2 weeks, T4 - 4 weeks using atomic absorption spectrophotometer (AAS). The results showed a mean inhibition zone of 2.57 + 0.17 mm for antimicrobial activity for test group which is clinically significant compared to the control group which showed no inhibition zone. Friedman test was used to compare the silver release at 4 different time periods T1, T2, T3, and T4 and Wilcoxon rank test for pairwise comparison. The amount of silver ion accumulation into artificial saliva increased continuously as time elapsed and silver ion release is statistically significant between the measured time points (p = 0.001). The AgNPs coated elastomeric modules has definite antimicrobial activity compared non coated elastomeric modules. The durability of the coating was shorter. [ABSTRACT FROM AUTHOR]

Recently, the eco-friendly production of silver nanoparticles (AgNPs) has become a focal point for researchers. In India, the quest for cost-effective, non-hazardous compounds suitable for reducing and stabilizing AgNPs has been limited. This study explores the synthesis of AgNPs using Elettaria cardamomom seed extract. We evaluated the efficiency of silver ion (Ag+) reduction and AgNP formation from an aqueous AgNO3 solution combined with the cardamom seed extract. Characterization of the AgNPs was carried out through UV-vis spectroscopy, XRD, SEM, EDAX, and FTIR. This research presents a practical and efficient strategy for AgNP production. A formulation using readily available 1 mm aqueous AgNO3, known for its accessibility and therapeutic properties, was created with cardamom seed extract serving as both a capping and reducing agent. Within 30 minutes, the silver ions were reduced to AgNPs, resulting in a change from golden to dark brown-reddish tint. Various analytical techniques, including UV-vis spectroscopy and Fourier-transform infrared spectroscopy, were employed for characterization. This study introduces an affordable, robust, and renewable method using E. cardamomum seeds for AgNP synthesis, which is entirely eco-friendly and devoid of toxic chemicals. AgNPs hold promise for applications in cancer treatment and diagnosis, setting them apart from other noble metals. [ABSTRACT FROM AUTHOR]

The green synthesized silver nanoparticles (AgNPs) with the aqueous extract of the leaves of household vegetable, Trigonella foenumgraecum were characterized and tested for their anti-oxidant and anti-bacterial efficacy with sixteen human clinical isolates. The Formation of AgNPs was confirmed with the surface plasmon spectra of the dark brown solution centered at 448 nm. The Particle size calculated with XRD data was 41.23 nm and the SEM size ranged between 52.56 nm and 80.51 nm. The presence of -NH and -OH groups that effectively react and reduce Ag+ ions to Ag0 was evident from the FT-IR spectra. The particles are predominantly spherical in shape and varied from 5 to 80 nm in size. As Suggested from the analysis by SEM and TEM, majority of them fall between 5 nm and 20 nm. A composite solution of AgNPs with polyvinyl alcohol (PVA) was electrospun into films and tested on 8 human clinical isolates including methicillin-resistant Staphylococcus aureus (MRSA). The PVA-AgNP films showed enormous activity against the MRSA prompting further study as wound dressings in the Wistar albino rat model. Although the animal study was abruptly terminated owing to the pandemic-induced lock down, the preliminary study results for 9 days suggest the potential clinical applications of these wound dressings. The synthesized AgNPs with and without PVA demonstrated good anti-oxidant activity and highly significant (P = 0.001) zones of inhibition with eighteen clinical isolates were tested. [ABSTRACT FROM AUTHOR]