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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]

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]

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 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]

A green-synthesis method for silver nanoparticles (Ag NPs) is a scientific breakthrough. Using sunflower plant extracts, this approach uses metallic and botanical synergy. Naturally occurring and renewable extracts reduce, chelate, stabilize, bind, and precipitate. The Ag nanoparticles' X-ray diffraction (XRD) crystal structure was cubic. Average nanoparticle crystallite size was 31.18 nm. Energy-dispersive X-ray spectroscopy (EDX) detected silver. Field Emission Scanning Electron Microscope (FESEM) examination revealed that the particles were Ag (silver) and spherical, averaging 31.23nm. Diffuse Reflectance Spectroscopy also indicated a 2.7 eV optical gap. Using many characterization methods, nanostructured silver was synthesized during this procedure. Biological efficacy assays can evaluate hierarchically porous silver's antibacterial properties. In the previous five years, strategies against Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus mutans, Ecoli, and Candida albicans, Penicillium spp., and Aspergillus spp. were essential. Data demonstrates that these structures are attractive antibacterial choices. A majority of Ag NPs are natural bacterium substitutes for Staphylococcus aureus, pseudomonas aeruginosa, Streptococcus mutans, and Ecoli. Also against various fungi: The immune systems of immunocompromised hosts are threatened by yeasts such Candida albicans, Penicillium, and Aspergillus.measured. It calls into doubt the study's efficacy in antibacterial and other 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]

To develop the biorefinery concept around the hydrothermal carbonization (HTC) process, it is essential to take advantage of the spent liquor (SL) produced. In general, SLs were reported to be treated by anaerobic digestion; however, some molecules present in SL are considered biological inhibitors. Nonetheless, this might be advantageous as these molecules exhibit antioxidant activity, opening a new valorization alternative as green reducing and capping agents for particle synthesis. Among the hydrothermally treated biomasses, the SL from Jatropha fruit husk (JFH) presented the highest antioxidant activity (TEAC ∼ 1597 µM g−1), increasing its capability to form metal nanoparticles due to their reducing effect. Still, nanoparticle aggregation was observed, evidencing its lack of capping effect. In this sense, the present study provides a novel approach to recovering the organic compounds from HTC spent liquor (OC-HTCSL) in viscous concentrates by evaporating the remaining water. Surprisingly, the JFH sample showed the lowest antioxidant activity and phenolic content after concentration. Nevertheless, this concentrate reflected a capping effect for the LED-assisted synthesis of silver nanoparticles. Stable silver colloids containing nanoparticles with an average diameter of 17 nm were successfully obtained. These silver nanoparticles retained their original morphology after being stored for six months. This research suggests that a lower antioxidant activity and phenolic content of the OC-HTCSL concentrate might be more effective in forming silver nanoparticles. [Display omitted] • HTC spent liquors can be used for sustainable nanoparticle synthesis. • Concentrates from HTC spent liquors exhibit reducing and capping effects. • Concentrate from Jatropha fruit husk produced stable nanoparticles. • Nanoparticles of 17 nm were produced using the Jatropha fruit husk concentrate. [ABSTRACT FROM AUTHOR]

In this study, we developed a novel nanocomposite by synthesizing zinc (ZnNPs), copper (CuNPs), and silver (AgNPs) nanoparticles using olive leaf extract and incorporating them into a chitosan polymer. This approach combines the biocompatibility of chitosan with the antimicrobial and anticancer properties of metal nanoparticles, enhanced by the phytochemical richness of olive leaf extract. The significance of our research lies in its potential to offer a biodegradable and stable alternative to conventional antibiotics and cancer treatments, particularly in combating multidrug-resistant bacteria and various cancer types. Comprehensive characterization through Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Transmission Electron Microscopy (TEM) confirmed the successful synthesis of the nanocomposites, with an average size of ~22.6 nm. Phytochemical analysis highlighted the antioxidant-rich composition of both the olive leaf extract and the nanoparticles themselves. Functionally, the synthesized nanoparticles exhibited potent antimicrobial activity against multidrug-resistant bacterial strains, outperforming traditional antibiotics by inhibiting key resistance genes (ermC, tetX3-q, blaZ, and Ery-msrA). In anticancer assessments, the nanoparticles showed selective cytotoxicity towards cancer cells in a concentration-dependent manner, with CuNPs and AgNPs showing particularly strong anticancer effects, while demonstrating minimal toxicity towards normal cells. ZnNPs were noted for their low cytotoxicity, highlighting the safety profile of these nanoparticles. Further, the nanoparticles induced apoptosis in cancer cells, as evidenced by the modulation of oncogenes (P21, P53, and BCL2), suggesting their therapeutic potential. The findings of our study underscore the versatile applications of these biogenic nanoparticles in developing safer and more effective antimicrobial and anticancer therapies. [Display omitted] [ABSTRACT FROM AUTHOR]

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

[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]

Infectious disease is the leading cause of death globally, viruses generally affect health care and social and economic development. In addition, adverse side effects from prolonged use and the rapid development of drug resistance to currently available treatments are serious and unreasonable public health concerns. Therefore, we must work intensively to develop new treatment strategies. With the use of nanoparticles in the field of biomedicine and their interaction with microorganisms, this leads to a rapid revolution by offering advantages in both diagnostic and therapeutic applications. One of the most unique physical properties of nanoparticles is that they have benefits associated with drug delivery. This is mostly owing to particle size (which influences bioavailability and turnaround time), a high surface area to volume ratio (which improves solubility relative to bigger particles), an adjustable surface charge with encapsulation capacity, and the ability to accept large drug payloads. These features, which are not shared by bulk materials of the same composition, make nanoparticle drug delivery systems good candidates for further investigation in order to obtain and/or improve therapeutic effects. [Display omitted] • Green technique is non-toxic, easy, cost-effective, and environmentally beneficial for nanoparticles production. • A variety of approaches are used to classify nanoparticles as two-dimensional like nanotubes) or three-dimensional (e.g., dendrimers, spherical NPs). • Metal nanoparticles and their oxides is a promising contender for developing a new class of antibacterial agents. • NPs are used in bio sensing, drug delivery, bio imaging, electronics, medicine, and water treatment. [ABSTRACT FROM AUTHOR]