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In this work, harvested mushroom substrate (HMS) has been explored for the first time through a comprehensive optimization study for the green synthesis of silver nanoparticles (AgNPs). A multiple response central composite design with three parameters: pH of the reaction mixture, temperature, and incubation period at three distinct levels was employed in the optimization study. The particle size of AgNPs, UV absorbance, and the percentage of Ag/Cl elemental ratio were considered as the response parameters. For each response variable examined the model used was found to be significant (P < 0.05). The ideal conditions were: pH 8.9, a temperature of 59.4 °C, and an incubation period of 48.5 h. The UV–visible spectra of AgNPs indicated that the absorption maxima for AgNP–3 were 414 nm, 420 for AgNPs–2, and 457 for AgNPs-1. The XRD analysis of AgNPs-3 and AgNPs-2 show a large diffraction peak at ∼38.2°, ∼44.2°, ∼64.4°, and ∼77.4°, respectively, which relate to the planes of polycrystalline face-centered cubic (fcc) silver. Additionally, the XRD result of AgNPs–1, reveals diffraction characteristics of AgCl planes (111, 200, 220, 311, 222, and 400). The TEM investigations indicated that the smallest particles were synthesized at pH 9 with average diameters of 35 ± 6 nm (AgNPs–3). The zeta potentials of the AgNPs are −36 (AgNPs–3), −28 (AgNPs–2), and −19 (AgNPs–1) mV, respectively. The distinct IR peak at 3400, 1634, and 1383 cm−1 indicated the typical vibration of phenols, proteins, and alkaloids, respectively. The AgNPs were further evaluated against gram (+) strain Bacillus subtilis (MTCC 736) and gram (−) strain Escherichia coli (MTCC 68). All of the NPs tested positive for antibacterial activity against both bacterial strains. The study makes a sustainable alternative to disposing of HMS to achieve the Sustainable Development Goals (SDGs). [Display omitted] • Harvested Mushroom Substrate utilized for the synthesis of silver nanoparticles. • The synthesis process was further optimized with central composite design. • PH > 9 yielded better morphology of synthesized silver nanoparticles. • The average size of the silver nanoparticles at pH > 9 was 35 ± 6 nm. • Highest bactericidal activity of silver nanoparticles were observed in 6.96 ± 0.03 ppm. [ABSTRACT FROM AUTHOR]

Activated carbon (AC) supported palladium cobalt bimetallic nanoparticles (PdCo@AC NPs) were obtained by green synthesis method using Cinnamomum verum (C. Verum) extract. The obtained NPs were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Crystallography (XRD), Transmission Electron Microscope (TEM) and Ultraviolet Visible (UV-VIS) spectroscopy, and the functional groups and morphology of the nanoparticle were elucidated. The resulting particle size was found to be 2.467 nm. NPs were evaluated using Cyclic Voltammetry (CV), Scan Rate (SR), and Differential Pulse Voltammetry (DPV) techniques for potential dopamine sensors application. According to the obtained DPV results, Limit of Detection (LOD) and Limit of Quantitation (LOQ) values are found to be 5.68 pM and 17.21 pM, respectively. It was also observed that AC supported PdCo nanoparticles obtained from C. verum extract sensed dopamine quite well. Besides, to examine the antibacterial properties of NPs, antibacterial analyzes were performed with Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus). It was observed that it showed good antibacterial properties against gram positive (S. aureus) and gram negative (E. coli) bacteria. The study gave important results in terms of the synthesis of bimetallic NPs using the green synthesis method and their usability in different areas. With this study, it was observed that a good antibacterial dopamine sensor were obtained with the successful biogenic synthesis of AC supported PdCo bimetallic NPs. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize Ag NPs as a green catalyst for photocatalytic activity and to examine their biological activities. It was determined that they have high activity in catalytic and biological activities. The green synthesis which is an environmentally friendly and inexpensive method was used to synthesize Ag-NPs using Linum usitatissimum as a reducing agent. Transmission electron microscopy (TEM), infrared to Fourier transform infrared (FTIR) spectroscopy, UV-Visible (UV–Vis) spectroscopy, and X-ray diffraction (XRD) were used to characterize the Ag NPs. In UV–Vis examination, Ag-NPs had intense peaks in the 435 nm region. The antibacterial activity of Ag NPs was investigated, and Ag NPs showed a high lethal effect against S. aureus, E. coli, B. subtilis, and MRSA. In addition, Ag NPs were tested for anticancer activity against the HT-29 colon cancer cell line, MDA-MB-231 breast cancer cell line, healthy cell line L929-Murine Fibroblast cell Lines, and MIA PaCa-2 human pancreatic cancer cell line at various concentrations (1–160 μg/mL) and showed a high anticancerogenic properties against MDA-MB-231 cells. Ag NPs showed the ability of DNA cleavage activity. Also, the antioxidant activity of Ag NPs against DPPH was found to be 80% approximately. Furthermore, the photocatalytic activity of Ag NPs against methylene blue (MB) was determined to be 67.13% at the 180th min. In addition, it was observed that biogenic Ag NPs have high electrocatalytic activity for hydrogen peroxide (H 2 O 2) detection. In the sensor based on Ag NPs, linearity from 1 μM to 5 μM was observed with a detection limit (LOD) of 1.323 μM for H 2 O 2. According to these results, we conclude that the biogenic Ag NPs synthesized using Linum usitatissimum extract can be developed as an efficient biological agent as an antibacterial and anticancer also can be used as a photocatalyst for industrial wastewater treatment to prevent wastewater pollution. [ABSTRACT FROM AUTHOR]

In order to be used in food packaging, the study aims to develop a composite film based on microcrystalline cellulose (MCC) and coated with silver nanoparticles (AgNPs). The MCC was derived from sugar cane bagasse. Protein, starch, and poly-ethylene glycol 1500 (PEG-1500) are employed to improve the tensile strength, flexibility, and durability of the packaging film. The AgNPs was synthesized by a green route employing Azadirachtaindica leaf extract as reducing agent. The determined average crystallite size of AgNPs was seen at 20 nm. The X-ray diffraction (XRD) studies of the final film prepared have an elevated peak with a crystallinity of 37.5%. The scanning electron microscopic images (SEM) of the AgNPs and the prepared samples, reveal their surface morphology. The Fourier transform infrared spectroscopic studies (FT-IR) disclose the functional group changes during the film preparation. The antibacterial activity of the amalgamated AgNPs against five bacterial pathogens studied was found to be highly active against tested food pathogens, except for Proteus vulgari. When coated over a vegetable, the produced nanocomposite film displayed an increased shelf life for the vegetable by limiting the decay impact caused by food pathogens. According to the findings, the AgNPs-impregnated MCC/Starch/Whey protein has the potential to be employed as an antimicrobial packaging material. [Display omitted] • Micro crystalline cellulose (MCC) based composite film impregnated with silver nanoparticles (agnps) has been synthesized. • Synthesized micro crystalline cellulose (MCC) utilized for food packaging applications. • AgNPs-impregnated MCC/Starch/Whey protein has employed as antimicrobial packaging material. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric hydrogels are a unique class of macromolecular networks that can hold a large fraction of an aqueous solvent within their structures. They are particularly suitable for biomedical applications including controlled drug delivery, because of their ability to stimulate biological tissues. Many hydrogel-based networks have been designed and fabricated to meet the needs of pharmaceutical and medical fields. The investigation deals with the environment friendly synthesis of biodegradable semi interpenetrating hydrogel networks based on cross-linked poly(acrylamide) through an optimized rapid redox solution polymerization with N, N′Methylenebisacrylamide (MBA) in presence of Carboxymethylcellulose (CMC).The silver nanoparticles within hydrogel networks as nano reactors have been prepared by green synthesis via insitu reduction of silver nitrate (AgNO 3 ) using Azadirachta Indica (Neem) plant extract under atmospheric conditions. The synthesized nanocomposites were characterised by FTIR spectroscopy, UV–Visible Spectroscopy, Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Dynamic light scattering (DLS) technique. The thermal properties of the nanocomposite was analyzed by Thermogravimetric Analysis (TGA). The pH response and drug release profile of the synthesised biodegradable Silver-Hydrogel nanocomposite was investigated. Further, it was observed that physicochemical interaction between the polymeric nanocomposites and drug influences the degree of matrix swelling and therefore, its porosity and diffusion release process. [ABSTRACT FROM AUTHOR]

In this work, silver nanoparticles (AgNPs) were synthesized solely using catechin (Ct), a natural polyphenol, then their effects on the growth and metabolism of Aspergillus niger GM13 were investigated using 7.5 and 15 ppm of nanoparticles. AgNPs-Ct, induced physio-metabolic changes activating different stress compensation mechanisms that affect the fungal growth and survival. In particular, 15 ppm of AgNPs-Ct leads to a reduction of 81% of the mycelia biomass. The stress responses in the presence of AgNPs-Ct were further determined by overall cell changes through the production of reactive oxygen species (ROS) by the fungal hyphae. The increase in ROS production confirmed cellular oxidative stress which, together with membrane damage, can be considered to be the main antifungal effect. Adaptative fungal responses during AgNPs-Ct treatment were linked to a high accumulation of trehalose, glycerol, citric and oxalic acid, and several important enzymes involved in the catabolism of nutrients for cell growth, such as acid phosphatase, Naphthol-ASBI phosphohydrolase. The exposure to AgNPs-Ct also triggers changes in the production of VOC derivating from the α- or β-oxidation of fatty acids as alcohols, aldehydes, alkanes, and acids. Herein, the antifungal effect of AgNPs-Ct is demonstrated, elucidating the impact on its physio-metabolic profile. • Surfactant-free AgNPs were synthesized in water exclusively using catechin (Ct). • AgNPs-Ct physio-metabolic effects on A. niger growth were monitored. • AgNPs-Ct induces a redox homeostasis imbalance and osmotic disequilibrium. • Adaptation and defense mechanisms of A. niger were evidenced. • AgNPs-Ct are sustainable emerging biocontrol agents with promising features. [ABSTRACT FROM AUTHOR]

Increasing demand of pure and accessible water and improper disposal of waste into the existing water resources are the major challenges for sustainable development. Nanoscale technology is an effective approach that is increasingly being applied to water remediation. Compared to conventional water treatment processes, silver nanotechnology has been demonstrated to have advantages due to its anti-microbial and oligodynamic (biocidal) properties. This review is focused on environmentally friendly green syntheses of silver nanoparticles (AgNPs) and their applications for the disinfection and microbial control of wastewater. A bibliometric keyword analysis is conducted to unveil important keywords and topics in the utilisation of AgNPs for water treatment applications. The effectiveness of AgNPs, as both free nanoparticles (NPs) or as supported NPs (nanocomposites), to deal with noxious pollutants like complex dyes, heavy metals as well as emerging pollutants of concern is also discussed. This knowledge dataset will be helpful for researchers to identify and utilise the distinctive features of AgNPs and will hopefully stimulate the development of novel solutions to improve wastewater treatment. This review will also help researchers to prepare effective water management strategies using nano silver-based systems manufactured using green chemistry. [Display omitted] • Evolution in research on AgNPs for water treatment is examined bibliometrically • Bio-based synthesis of AgNPs is simple, robust, eco-friendly and cost-effective. • AgNPs composites can be used to remove emerging pollutants. • Antibacterial mechanism of AgNPs is discussed for disinfection and microbial control. • Future perspectives and their potential applications are proposed. [ABSTRACT FROM AUTHOR]

Plant-mediated synthesis of silver nanoparticles (Ag NPs) is a green and economically viable method, which can offer numerous benefits over traditional chemical and physical methods. In this paper, three fruit extracts (tomato, orange, and grapefruit) served simultaneously as stabilizing and reducing agents during the biosynthesis of Ag NPs. The formation of Ag NPs, were monitored using the UV–visible absorption spectra of Ag NPs which exhibited three distinct bands centered at 439, 413, and 410 nm. SEM and TEM analysis indicated that these bands corresponded to three distinct spherical-shaped Ag NPs having average particle sizes of 73, 24, and 31 nm, respectively. XRD and EDS spectral analyses were used to verify the degree of crystallinity, nanostructure, and presence of Ag NPs. Advanced analysis using XPS, FTIR, and GC-MS indicated that the Ag NPs were coated with a variety of organic compounds including acids, aldehydes, esters, and ketones, indicating that fruit derived phytochemicals had a significant role in synthesis, and subsequently a mechanism of Ag NPs formation was proposed. The fabricated nanoparticles were also successfully used in Fenton-like oxidation for the environmental remediation of estrone and estriol, with removal efficiencies of 52.1 and 35.9%, respectively. • Three different fruit extracts were used to synthesize Ag NPs. • Biomolecules in fruit extracts were confirmed. • Formation of Ag NPs by fruit extracts was proposed. • Green Ag NPs were useful as a catalyst to remove estrogen from aqueous solution. [ABSTRACT FROM AUTHOR]

Hypothesis Biological synthesis of silver nanoparticles is a cost effective natural process where the phytochemicals specifically phenols, flavonoids and terpenoids present in the plant extracts act as capping and reducing agent. Due to their nano size regime the silver nanoparticles may directly bind to the DNA of the pathogenic bacterial strains leading to higher antimicrobial activity. Experiment In the current study silver nanoparticles were synthesised using plant extracts from different origin Cucurbita maxima (petals), Moringa oleifera (leaves) and Acorus calamus (rhizome). The synthesised nanoparticles were characterized by UV–visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), field emission scanning electron microscopy (Fe-SEM) and Fourier transform infrared spectroscopy (FTIR). Finding Highly crystalline, roughly spherical and cuboidal silver nanoparticles of 30–70 nm in size were synthesised. The nanoparticles provided strong antimicrobial activity against pathogenic strains. The effect of the synthesised nanoparticles against A431 skin cancer cell line was tested for their toxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) dye. The IC 50 values of 82.39 ± 3.1, 83.57 ± 3.9 and 78.58 ± 2.7 μg/ml were calculated for silver nanoparticles synthesised by C. maxima , M. oleifera and A. calamus respectively. [ABSTRACT FROM AUTHOR]

In this work, silver nanoparticles have been synthesized by wet chemical technique, green synthesis and microbial methods. Silver nitrate (10 −3 M) was used with aqueous extract to produce silver nanoparticles. From the results it was observed that the yield of nanoparticles was high in green synthesis. The size of the silver nanoparticles was determined from Scanning Electron Microscope analysis (SEM). Fourier Transform Infrared spectroscopy (FTIR) was carried out to determine the presence of biomolecules in them. Its cytotoxic effect was studied in cancerous cell line and normal cell line. MTT assay was done to test its optimal concentration and efficacy which gives valuable information for the use of silver nanoparticles for future cancer therapy. [ABSTRACT FROM AUTHOR]

Despite the development potential in the field of nanotechnology, there is a concern about possible effects of nanoparticles on the environment and human health. In this study, silver nanoparticles (AgNPs) were synthesized by ‘green’ and ‘chemical’ methods. In the wet-chemistry method, sodium borohydrate, sodium citrate and silver nitrate were used as raw materials. Leaf extract of Nigella sativa was used as reducing as well as capping agent to reduce silver nitrate in the green synthesis method. In addition, toxic responses of both synthesized AgNPs were monitored on bone-building stem cells of mice as well as seed germination and seedling growth of six different plants (Lolium, wheat, bean and common vetch, lettuce and canola). In both synthesis methods, the colorless reaction mixtures turned brown and UV–visible spectra confirmed the presence of silver nanoparticles. Scanning electron microscope (SEM) observations revealed the predominance of silver nanosized crystallites and fourier transform infra-red spectroscopy (FTIR) indicated the role of different functional groups in the synthetic process. MTT assay showed cell viability of bone-building stem cells of mice was further in the green AgNPs synthesized using black cumin extract than chemical AgNPs. IC50 (inhibitory concentrations) values for seed germination, root and shoot length for 6 plants in green AgNPs exposures were higher than the chemical AgNPs. These results suggest that cytotoxicity and phytotoxicity of the green synthesized AgNPs were significantly less than wet-chemistry synthesized ones. This study indicated an economical, simple and efficient ecofriendly technique using leaves of N. sativa for synthesis of AgNPs and confirmed that green AgNPs are safer than chemically-synthesized AgNPs. [ABSTRACT FROM AUTHOR]

During this study, we report the green synthesis of silver nanoparticles (Ag NPs) using Euphorbia helioscopia Linn leaf extract for the synthesis of propargylamines. Also, the structural and optical properties are studied. The synthesized nanoparticles are characterized by TEM, XRD, FT-IR and UV–visible techniques. UV–visible studies show an absorption band at 440 nm due to surface plasmon resonance (SPR) of the silver nanoparticles. Furthermore, the catalyst exhibits high catalytic activity, superior cycling stability and excellent substrate applicability. [ABSTRACT FROM AUTHOR]

In this study a synthetic approach for the stable, mono-dispersed high yielding bimetallic (Ag-Se) nanoparticles by quercetin and gallic acid is described. The bimetallic nanoparticles were synthesized at room temperature. Different reaction parameters (concentration of quercetin, gallic acid and Ag/Se salt, pH, temperature and reaction time) were optimized to control the properties of nanoparticles. The nanoparticles were characterized by various analytical techniques and their size was determined to be 30-35 nm. Our findings suggest that both the reduction as well as stabilization of nanoparticles were achieved by the flavonoids and phenolics. This study describes the efficacy of quercetin and gallic acid mediated synthesis of bimetallic (Ag-Se) nanoparticles and their in vitro antioxidant, antimicrobial (Gram-positive and Gram-negative bacteria) and antitumor potentials. The synthesized Ag-Se nanoparticles were used as anticancer agents for Dalton lymphoma (DL) cells and in in vitro 80% of its viability was reduced at 50 μg/mL. [ABSTRACT FROM AUTHOR]

The demand for the green synthesis of nanoparticles has gained prominence over the conventional chemical and physical syntheses, which often entails toxic chemicals, energy consumption and ultimately lead to negative environmental impact. In the green synthesis approach, naturally available bio-compounds found in plants and fungi can be effective and have been proven to be alternative reducing agents. Fungi or mushrooms are particularly interesting due to their high content of bioactive compounds, which can serve as excellent reducing agents in the synthesis of nanoparticles. Apart from the economic and environmental benefits, such as ease of availability, low synthesis/production cost, safe and no toxicity, the nanoparticles synthesized from this green method have unique physical and chemical properties. Stabilisation of the nanoparticles in an aqueous solution is exceedingly high, even after prolonged storage with unperturbed size uniformity. Biological properties were significantly improved with higher biocompatibility, anti-microbial, anti-oxidant and anti-cancer properties. These remarkable properties allow further exploration in their applications both in the medical and agricultural fields. This review aims to explore the mushroom-mediated biosynthesis of nanomaterials, specifically the mechanism and bio-compounds involved in the synthesis and their interactions for the stabilisation of nanoparticles. Various metal and non-metal nanoparticles have been discussed along with their synthesis techniques and parameters, making them ideal for specific industrial, agricultural, and medical applications. Only recent developments have been explored in this review. [Display omitted] • A detailed mechanism contributing to the mycogenic synthesis of NPs has been described. • Demonstrates the role of different mushroom species to different sizes, shapes, stability and homogeneity of NPs. • Provides ideal physical and chemical properties of the mycogenic synthesized NPs. • Illustrates properties as well as unique applications arising from species-specific NPs. • Explores wider applications extending to biomedical, environmental and industrial sectors. [ABSTRACT FROM AUTHOR]

A green synthesis method for nanoscale silver using β-cyclodextrin as both reducing agent and stabilizer was developed. β-cyclodextrin was used not only as a reducing agent but also a stabilizing agent for nano-silver, and is also an excellent detection substrate due to its special structure (inner hydrophobic and outer hydrophilic ring structure). Then, the green synthesized silver nanoparticles were used as Surface-enhanced Raman spectroscopy (SERS) enhanced substrates to detect polycyclic aromatic hydrocarbons, such as: anthracene, pyrene, chrysene and triphenylene. The SERS substrate can be used for both quantitative detection of the four polycyclic aromatic hydrocarbons and qualitative identification of mixtures of these hydrocarbons. This synthesis method is simple and convenient, having great potential in simultaneous and rapid detection of environmental organic pollutants. Image 1 • A green synthesis method of nano silver surface reinforced substrate is introduced in this paper. • β-cyclodextrin could be used both as a reducing agent and as a stabilizer because of its unique structure. • The enhanced substrate synthesized by this method can be used for the detection of polycyclic aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

• Cost-effective synthesis of silver nanoparticles using Crataegus pentagyna fruit extract is reports for the first time. • The CP -AgNPs was characterized using XRD, FT-IR, EDS, TEM, SEM, DLS and UV–Vis. • Spherical CP -AgNPs showed a high photocatalytic and antibacterial activities in the degradation of organic pollutants and various bacteria, respectively. • As-synthesized silver nanoparticles were used against multi-drug resistance gram negative and gram positive of bacteria. In this work, a cost-effective/green/high-efficient/facile process for the preparation of silver nanoparticles using C. pentagyna (CP -AgNPs) fruit extractas as reducing agent and capping agent was reported. The influence of different parameters including temperature, pH, concentration and time were studied to reach optimum conditions. The as-synthesized CP -AgNPs were characterized using UV/Vis, XRD, SEM, TEM, EDS and DLS analysis. Regular, spherical morphology and homogeneous of CP -AgNPs with a mean particles size of 25–45 nm was determined from TEM images. The CP -AgNPs in presence of sunlight catalyzed the degradation of the organic contaminant dyes, rhodmine b (RhB), eosin (EY) and methylene blue (MB) with percent degradation of 85% and 70% and 78%, respectively. In addition, CP -AgNPs exhibit antibacterial activities against seven ATCC strains of bacteria and eight strains of drug-resistant bacteria. Due to the results, CP -AgNPs enhanced antimicrobial potential against S. aureus, E. faecalis , P. aeruginosa , A. baumannii and E. coli with MIC and MBC of (0.11, 7.1 µg/ml), (0.11, 1.7 µg/ml), (0.11, 0.22 µg/ml), (0.11, 0.22) and (0.11, 0.44 µg/ml), respectively. Generally, CP-AgNPs have excellent potential application for the photocatalytic degradation of organic pollutant and in the development of antibacterial materials. [ABSTRACT FROM AUTHOR]