Biological agents for synthesis of nanoparticles and their applications

Characterization and potentiality of plant-derived silver nanoparticles for enhancement of biomass and hydrogen production in Chlorella sp. under nitrogen deprived condition

Energy is a crucial entity for the development and it has various alternative forms of energy sources. Recently, the synthesis of nanoparticles using benign biocatalyst has attracted increased attention. In this study, silver nanoparticles were synthesized and characterized using Azadirachta indica plant-derived phytochemical as the reducing agent. Biomass of the microalga Chlorella sp. cultivated in BG11 medium increased after exposure to low concentrations of up to 0.48 mg L-1 AgNPs. In addition, algal cells treated with 0.24 mg L-1 AgNPs and cultivated in BG110 medium which contained no nitrogen source showed the highest hydrogen yield of 10.8 mmol L-1, whereas the untreated cells under the same conditions showed very low hydrogen yield of 0.003 mmol L-1. The enhanced hydrogen production observed in the treated cells was consistent with an increase in hydrogenase activity. Treatment of BG110 grown cells with low concentration of green synthesized AgNPs at 0.24 mg L-1 enhanced hydrogenase activity with a 5-fold increase of enzyme activity compared to untreated BG110 grown cells. In addition, to improve photolytic water splitting efficiency for hydrogen production, cells treated with AgNPs at 0.24 mg L-1 showed highest oxygen evolution signifying improvement in photosynthesis. The silver nanoparticles synthesized using phytochemicals derived from plant enhanced both microalgal biomass and hydrogen production with an added advantage of CO2 reduction which could be achieved due to an increase in biomass. Hence, treating microalgae with nanoparticles provided a promising strategy to reduce the atmospheric carbon dioxide as well as increasing production of hydrogen as clean energy.

Recent Trends in Biologically Synthesized Metal Nanoparticles and their Biomedical Applications: a Review

In recent years, biologically synthesized metal nanoparticles have emerged as a dynamic field of research with significant implications for biomedical applications. This review explores the latest trends in the synthesis of metal nanoparticles using biological methods, encompassing plant extracts and microorganisms such as bacteria, yeasts, and fungi. These innovative approaches offer a sustainable, cost-effective, and environmentally friendly alternative to conventional chemical synthesis methods. Moreover, this review delves into the multifaceted biomedical applications of biologically synthesized metal nanoparticles. These applications include drug delivery systems, diagnostics, therapeutics, and imaging technologies, showcasing the versatility and promise of these nanomaterials in addressing contemporary biomedical challenges. In addition, the review addresses the critical issue of cytotoxicity, offering insights into the safety and viability of these biologically derived NPs for medical use. The exploration of recent trends and advancements in this field underscores the transformative potential of biologically synthesized metal nanoparticles in revolutionizing biomedical research and healthcare.

Sustainable Synthesis of Novel Green-Based Nanoparticles for Therapeutic Interventions and Environmental Remediation

The advancement in nanotechnology has completely revolutionized various fields, including pharmaceutical sciences, and streamlined the potential therapeutic of many diseases that endanger human life. The synthesis of green nanoparticles by biological processes is an aspect of the newly emerging scientific field known as "green nanotechnology". Due to their safe, eco-friendly, nontoxic nature, green synthesis tools are better suited to produce nanoparticles between 1 and 100 nm. Nanoformulation of different types of nanoparticles has been made possible by using green production techniques and commercially feasible novel precursors, such as seed extracts, algae, and fungi, that act as potent reducing, capping, and stabilizing agents. In addition to this, the biofunctionalization of nanoparticles has also broadened its horizon in the field of environmental remediation and various novel therapeutic innovations including wound healing, antimicrobial, anticancer, and nano biosensing. However, the major challenge pertaining to green nanotechnology is the agglomeration of nanoparticles that may alter the surface topology, which can affect biological physiology, thereby contributing to system toxicity. Therefore, a thorough grasp of nanoparticle toxicity and biocompatibility is required to harness the applications of nanotechnology in therapeutics.

Phyto- and biochemical study on cape gooseberry (physalis peruviana L.) extract incorporated with metal nanoparticles against hepatic injury induced in rats

The study aimed to investigate the role of metal nanoparticles (M-NPs) in improving the efficiency of Physalis peruviana (Cape gooseberry) juice, which is rich in numerous important therapeutic phytochemicals. Therefore, it was subsequently studied against chemically-induced toxicity in rats. The present study demonstrated that C. gooseberry juice was used for the biosynthesis of silver (Ag-NPs) and zinc oxide nanoparticles (ZnO-NPs). The ZnO-C. gooseberry nano-extract exhibited higher in vitro biological activities compared to the other extracts. It was also found to be safer when administered orally. Moreover, it demonstrated a greater ameliorative effect against hepatotoxicity induced by carbon tetrachloride (CCl4) in rats. It restored the integrity of the liver tissue by increasing levels of antioxidant enzymes and reducing the inflammatory markers significantly (p ≤ 0.05). The study found that the ZnO-C. gooseberry nano-extract demonstrated greater efficacy in combating CCl4-induced hepatotoxicity compared to the other extracts.

Advances in the Optimization of Fe Nanoparticles: Unlocking Antifungal Properties for Biomedical Applications

In recent years, nanotechnology has achieved a remarkable status in shaping the future of biological applications, especially in combating fungal diseases. Owing to excellence in nanotechnology, iron nanoparticles (Fe NPs) have gained enormous attention in recent years. In this review, we have provided a comprehensive overview of Fe NPs covering key synthesis approaches and underlying working principles, the factors that influence their properties, essential characterization techniques, and the optimization of their antifungal potential. In addition, the diverse kinds of Fe NP delivery platforms that command highly effective release, with fewer toxic effects on patients, are of great significance in the medical field. The issues of biocompatibility, toxicity profiles, and applications of optimized Fe NPs in the field of biomedicine have also been described because these are the most significant factors determining their inclusion in clinical use. Besides this, the difficulties and regulations that exist in the transition from laboratory to experimental clinical studies (toxicity, specific standards, and safety concerns) of Fe NPs-based antifungal agents have been also summarized.

Revolution in Cancer Treatment: How Are Intelligently Designed Nanostructures Changing the Game?

Nanoparticles (NPs) are extremely important tools to overcome the limitations imposed by therapeutic agents and effectively overcome biological barriers. Smart designed/tuned nanostructures can be extremely effective for cancer treatment. The selection and design of nanostructures and the adjustment of size and surface properties are extremely important, especially for some precision treatments and drug delivery (DD). By designing specific methods, an important era can be opened in the biomedical field for personalized and precise treatment. Here, we focus on advances in the selection and design of nanostructures, as well as on how the structure and shape, size, charge, and surface properties of nanostructures in biological fluids (BFs) can be affected. We discussed the applications of specialized nanostructures in the therapy of head and neck cancer (HNC), which is a difficult and aggressive type of cancer to treat, to give an impetus for novel treatment approaches in this field. We also comprehensively touched on the shortcomings, current trends, and future perspectives when using nanostructures in the treatment of cancer.

Photo-catalytic dye degradation potentials of Ag-Pd bimetallic nanoparticles synthesized from Vitex negundo

Plant extracts are a great alternative to synthesizing nanoparticles of different metals and metal oxides. This green synthesis method has opened up numerous possibilities in various scientific domains. In present study, Leaf extract from Vitex negundo is a non-deciduous, long-lasting shrub from the Verbenaceae family is used as capping and reducing agents for the synthesis of silver and palladium nanoparticles. The characterization study UV-vis spectrophotometer analysis showed absorbance value around 320 nm which confirming that Ag-Pd nanoparticles have been successfully obtained. Further, SEM is used to investigate the morphology of Ag-Pd NPs, which revealing their spherical and rod-like configuration, aggregation, and the size of the particles are obtained between 50 and 100 nm. The successful synthesis of Ag-Pd NPs was further confirmed by the EDAX chart, which displayed the peak of Ag and Pd at bending energies between 0.5 and 1.5 keV. According to the quantitative study, Ag and Pd ions found about 5.24 and 13.28%, respectively. In addition, surface studies with TEM confirming that synthesized Ag-Pd NPs are predominates with spheres structure morphologies, with sizes averaging 11.20 nm and ranging from 10 to 20 nm. Further, Ag-Pd nanoparticles was applied as potential photocatalyst materials to degrade methylene blue dye and found about 85% of the degradation efficiency within 150 min of the sunlight exposure thus could be used as catalyst to removal of hazardous organic dye molecules.

Exploring glycans as vital biological macromolecules: A comprehensive review of advancements in biomedical frontiers

This comprehensive review delves into the intricate landscape of glycans and glycoconjugates, unraveling their multifaceted roles across diverse biological dimensions. From influencing fundamental cellular processes such as signaling, recognition, and adhesion to exerting profound effects at the molecular and genetic levels, these complex carbohydrate structures emerge as linchpins in cellular functions and interactions. The structural diversity of glycoconjugates, which can be specifically classified into glycoproteins, glycolipids, and proteoglycans, underscores their importance in shaping the architecture of cells. Beyond their structural roles, these molecules also play key functions in facilitating cellular communication and modulating recognition mechanisms. Further, glycans and glycoconjugates prove invaluable as biomarkers in disease diagnostics, particularly in cancer, where aberrant glycosylation patterns offer critical diagnostic cues. Furthermore, the review explores their promising therapeutic applications, ranging from the development of glycan-based nanomaterials for precise drug delivery to innovative interventions in cancer treatment. This review endeavors to comprehensively explore the intricate functions of glycans and glycoconjugates, with the primary goal of offering valuable insights into their extensive implications in both health and disease. Encompassing a broad spectrum of biological processes, the focus of the review aims to provide a comprehensive understanding of the significant roles played by glycans and glycoconjugates.

Sustainable Approaches in Green Synthesis of Silica Nanoparticles Using Extracts of Chlorella and Its Application

Silica nanoparticles, also known as SiO2 nanoparticles, have wider applications in biomedical, building, water treatment, agriculture, and food industries. It is used as an anticaking agent in the food industry, used to remove heavy metals from water, and used in cement-based materials. SiO2 nanoparticles synthesized by physical and chemical methods require high energy and use of toxic chemicals which is quite expensive, have a greater impact causing health-related issues, and have environmental side effects. Hence, there is a need to synthesize nanoparticles in an eco-friendly way. The biological or green synthesis method uses microbes, such as bacteria, fungi, algae, and plants for synthesizing nanoparticles. Algae contain natural biochemicals that act as reducing agents. These biomolecules are non-toxic as they are naturally occurring compounds and can be used to fabricate nanoparticles by avoiding the use of toxic chemicals in an eco-friendly method. In this study, silica nanoparticles were synthesized by green synthesis methods using microalgae extract. Further, the green synthesized silica nanoparticles were characterized using ultra violet-visible (UV-VIS) spectroscopy, Fourier transform-infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray analysis (EDAX). The antimicrobial activity of the silica nanoparticles against E. coli was studied. This study revealed that the nanoparticles can be synthesized using green synthesis methods with low cost, less toxic chemicals, eco-friendly, and have antimicrobial activity against E. coli.

Encapsulation of propolis extracted with methylal in the chitosan nanoparticles and its antibacterial and cell cytotoxicity studies

In this study we develop novel type of antibacterial chitosan-propolis NPs to improve theantimicrobial activity against various pathogens. To this aim, we primarily extracted propolis with methylal and ethanol as green solvents and its encapsulation with chitosan NPs. The developed propolis loaded chitosan NPs indicated antimicrobial and anti-biofilm properties against various gram positive and negative. FTIR revealed the successful encapsulation of the propolis extract with Ethanol (PE) and Methylal (PM) into the chitosan nano career matrix. HPLC and GC-MASS also confirmed the presence of flavonoids and phenols compounds of propolis extracted with both solvents. In addition, we confirmed the total phenolic and flavonoid compounds in propolis by calorimetric method of Folin-Ciocalteu and aluminum trichloride complex formation assays, respectively. PE-CH and PM-CH were optimized regarding physicochemical properties such as particle size, zeta potential, and poly dispersity index (PDI) index. DLS and SEM micrographs confirmed a spherical morphology in a range of 360-420 nm with Z potential values of 30-48 mV and PDI of 0.105-0.166 for PE-CH and PM-CH, respectively. The encapsulation efficiency was evaluated using colorimetric analysis, with median values ranging from 90 to 92%. The MIC values within the range of 2 to 230 µg/ml and MBC values between 3 to 346 μg/ml against both gram-positive and negative bacteria. While both PE and PM showed a significant reduction in the number of E. coli, S. aureus, and S. epidermidis, the use of PE-CH and PM-CH led to a statistically significant and greater reduction in number of E. coli, S. aureus, and S. epidermidis strains on the biofilm, pre-formed biofilm and planktonic phases. Besides, the DPPH assay showed significant antioxidant activity for these NPs within the range of 36 to 92%. MTT assay for MHFB-1, HFF, L929, MDF, and MCF-7 cells exhibited statistically significant differences in each other that show the IC50 between 60-160 µg/ml for normal cells and 20 for cancer cells. Finally the present study indicated that both PM and PM-CH greater than PE and PE-CH in which contain high flavonoid and phenolic contents with a high antioxidation potential antioxidant properties, which could be beneficial for cell proliferation and antibiotic and anticancer applications.

Microalgae as a potential natural source for the green synthesis of nanoparticles

The increasing global population is driving the development of alternative sources of food and energy, as well as better or new alternatives for health and environmental care, which represent key challenges in the field of biotechnology. Microalgae represent a very important source material to produce several high-value-added bioproducts. Due to the rapid changes in the modern world, there is a need to build new materials for use, including those in the nanometer size, although these developments may be chronological but often do not occur at a time. In the last few years, a new frontier has opened up at the interface of biotechnology and nanotechnology. This new frontier could help microalgae-based nanomaterials to possess new functions and abilities. Processes for the green synthesis of nanomaterials are being investigated, and the availability of biological resources such as microalgae is continuously being examined. The present review provides a concise overview of the recent advances in the synthesis, characterization, and applications of nanoparticles formed using a wide range of microalgae-based biosynthesis processes. Highlighting their innovative and sustainable potential in current research, our study contributes towards the in-depth understanding and provides latest updates on the alternatives offered by microalgae in the synthesis of nanomaterials.

Biosynthesis and Multifaceted Characterization of Breynia nivosa-Derived Silver Nanoparticles: An Eco-Friendly Approach for Biomedical Applications

This study presents an environmentally friendly synthesis of stable silver nanoparticles (Ag-NPs) using the methanolic extract of Breynia nivosa. Initial phytochemical analysis of the extract revealed the presence of alkaloids, flavonoids, glycosides, saponins, and tannins. Further characterization through high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) analyses identified a diverse array of bioactive compounds, including hydroquinone, stearic acid, neophytadiene, 9,12-octadecadienoic acid (Z,Z), methyl ester, and others. The addition of B. nivosa methanolic extract to an AgNO3 solution resulted in a color change, confirming the green synthesis of Ag-NPs through the reduction of AgNO3, as made evident by ultraviolet-visible (UV-vis) spectroscopy. X-ray diffraction (XRD) analysis provided valuable insights into the crystal structure, and scanning electron microscopy (SEM) analysis visualized the predominantly spherical shape of the Ag-NPs. However, the zeta (ζ)-potential and dynamic light scattering (DLS) analyses confirmed the stability and nanoscale dimensions of the synthesized Ag-NPs. Meanwhile, Fourier transform infrared (FT-IR) spectra exhibited peaks indicative of various functional groups, including carboxylic acids, phenols, alkanes, and isocyanates. These functional groups played a crucial role in both the reduction and capping processes of the Ag-NPs. The study further explored the antioxidant activity, cytotoxicity, acetylcholinesterase inhibition, and α-amylase inhibition activities of the Ag-NPs of the B. nivosa extract, demonstrating their potential for biomedical and therapeutic applications. In conclusion, this environmentally sustainable synthesis of Ag-NPs from the B. nivosa extract, enriched with bioactive secondary metabolites detected through HPLC and GC-MS analysis, holds promise for diverse applications in the burgeoning field of green nanotechnology.

Assessment of Silver Nanoparticles Derived from Brown Algae Sargassum vulgare: Insight into Antioxidants, Anticancer, Antibacterial and Hepatoprotective Effect

Algae are used as safe materials to fabricate novel nanoparticles to treat some diseases. Marine brown alga Sargassum vulgare are used to fabricate silver nanoparticles (Sv/Ag-NPs). The characterization of Sv/Ag-NPs was determined by TEM, EDX, Zeta potential, XRD, and UV spectroscopy. The Sv/Ag-NPs were investigated as antioxidant, anticancer, and antibacterial activities against Gram-positive bacteria Bacillus mojavensis PP400982, Staphylococcus caprae PP401704, Staphylococcus capitis PP402689, and Staphylococcus epidermidis PP403851. The activity of the Sv/Ag-NPs was evaluated as hepatoprotective in vitro in comparison with silymarin. The UV-visible spectrum of Sv/Ag-NPs appeared at 442 nm; the size of Sv/Ag-NPs is in range between 6.90 to 16.97 nm, and spherical in shape. Different concentrations of Sv/Ag-NPs possessed antioxidant, anticancer activities against (HepG-2), colon carcinoma (HCT-116), cervical carcinoma (HeLa), and prostate carcinoma (PC-3) with IC50 50.46, 45.84, 78.42, and 100.39 µg/mL, respectively. The Sv/Ag-NPs induced the cell viability of Hep G2 cells and hepatocytes treated with carbon tetrachloride. The Sv/Ag-NPs exhibited antibacterial activities against Staphylococcus caprae PP401704, Staphylococcus capitis PP402689, and Staphylococcus epidermidis PP403851. This study strongly suggests the silver nanoparticles derived from Sargassum vulgare showed potential hepato-protective effect against carbon tetrachloride-induced liver cells, and could be used as anticancer and antibacterial activities.

Harnessing nature's potential: Alpinia galanga methanolic extract mediated green synthesis of silver nanoparticle, characterization and evaluation of anti-neoplastic activity

With the advent of nanotechnology, the treatment of cancer is changing from a conventional to a nanoparticle-based approach. Thus, developing nanoparticles to treat cancer is an area of immense importance. We prepared silver nanoparticles (AgNPs) from methanolic extract of Alpinia galanga rhizome and characterized them by UV-Vis spectrophotometry, Fourier transform Infrared (FTIR) spectroscopy, Zetasizer, and Transmission electron Microscopy (TEM). UV-Vis spectrophotometry absorption spectrum showed surface plasmon between 400 and 480 nm. FTIR spectrum analysis implies that various phytochemicals/secondary metabolites are involved in the reduction, caping, and stabilization of AgNPs. The Zetasier result suggests that the particles formed are small in size with a low polydispersity index (PDI), suggesting a narrow range of particle distribution. The TEM image suggests that the particles formed are mostly of spherical morphology with nearly 20-25 nm. Further, the selected area electron diffraction (SAED) image showed five electron diffraction rings, suggesting the polycrystalline nature of the particles. The nanoparticles showed high anticancer efficacy against cervical cancer (SiHa) cell lines. The nanostructures showed dose-dependent inhibition with 40% killing observed at 6.25 µg/mL dose. The study showed an eco-friendly and cost-effective approach to the synthesis of AgNPs and provided insight into the development of antioxidant and anticancer agents.

Antimicrobial, antibiofilm, and antivirulence properties of Eisenia bicyclis-extracts and Eisenia bicyclis-gold nanoparticles towards microbial pathogens

Nanomaterials derived from seaweed have developed as an alternative option for fighting infections caused by biofilm-forming microbial pathogens. This research aimed to discover potential seaweed-derived nanomaterials with antimicrobial and antibiofilm action against bacterial and fungal pathogens. Among seven algal species, the extract from Eisenia bicyclis inhibited biofilms of Klebsiella pneumoniae, Staphylococcus aureus, and Listeria monocytogenes most effectively at sub-MIC levels. As a result, in the present study, E. bicyclis was chosen as a prospective seaweed for producing E. bicyclis-gold nanoparticles (EB-AuNPs). Furthermore, the mass spectra of E. bicyclis reveal the presence of a number of potentially beneficial chemicals. The polyhedral shape of the synthesized EB-AuNP with a size value of 154.74 ± 33.46 nm was extensively described. The lowest inhibitory concentration of EB-AuNPs against bacterial pathogens (e.g., L.monocytogenes, S. aureus, Pseudomonas aeruginosa, and K. pneumoniae) and fungal pathogens (Candida albicans) ranges from 512 to >2048 μg/mL. Sub-MIC of EB-AuNPs reduces biofilm formation in P. aeruginosa, K. pneumoniae, L. monocytogenes, and S. aureus by 57.22 %, 58.60 %, 33.80 %, and 91.13 %, respectively. EB-AuNPs eliminate the mature biofilm of K. pneumoniae at > MIC, MIC, and sub-MIC concentrations. Furthermore, EB-AuNPs at the sub-MIC level suppress key virulence factors generated by P. aeruginosa, including motility, protease activity, pyoverdine, and pyocyanin, whereas it also suppresses the production of staphyloxanthin virulence factor from S. aureus. The current research reveals that seaweed extracts and a biocompatible seaweed-AuNP have substantial antibacterial, antibiofilm, and antivirulence actions against bacterial and fungal pathogens.

Revisiting the smart metallic nanomaterials: advances in nanotechnology-based antimicrobials

Despite significant advancements in diagnostics and treatments over the years, the problem of antimicrobial drug resistance remains a pressing issue in public health. The reduced effectiveness of existing antimicrobial drugs has prompted efforts to seek alternative treatments for microbial pathogens or develop new drug candidates. Interestingly, nanomaterials are currently gaining global attention as a possible next-generation antibiotics. Nanotechnology holds significant importance, particularly when addressing infections caused by multi-drug-resistant organisms. Alternatively, these biomaterials can also be combined with antibiotics and other potent biomaterials, providing excellent synergistic effects. Over the past two decades, nanoparticles have gained significant attention among research communities. Despite the complexity of some of their synthesis strategies and chemistry, unrelenting efforts have been recorded in synthesizing potent and highly effective nanomaterials using different approaches. With the ongoing advancements in nanotechnology, integrating it into medical procedures presents novel approaches for improving the standard of patient healthcare. Although the field of nanotechnology offers promises, much remains to be learned to overcome the several inherent issues limiting their full translation to clinics. Here, we comprehensively discussed nanotechnology-based materials, focusing exclusively on metallic nanomaterials and highlighting the advances in their synthesis, chemistry, and mechanisms of action against bacterial pathogens. Importantly, we delve into the current challenges and prospects associated with the technology.

Photodynamic Antibacterial Therapy of Gallic Acid-Derived Carbon-Based Nanoparticles (GACNPs): Synthesis, Characterization, and Hydrogel Formulation

Carbon-based nanoparticles (CNPs) have gained recognition because of their good biocompatibility, easy preparation, and excellent phototherapy properties. In biomedicine applications, CNPs are widely applied as photodynamic agents for antibacterial purposes. Photodynamic therapy has been considered a candidate for antibacterial agents because of its noninvasiveness and minimal side effects, especially in the improvement in antibacterial activity against multidrug-resistant bacteria, compared with conventional antibiotic medicines. Here, we developed CNPs from an active polyhydroxy phenolic compound, namely, gallic acid, which has abundant hydroxyl groups that can yield photodynamic effects. Gallic acid CNPs (GACNPs) were rapidly fabricated via a microwave-assisted technique at 200 °C for 20 min. GACNPs revealed notable antibacterial properties against Gram-positive and Gram-negative bacteria, including Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The minimum inhibitory concentrations of GACNPs in S. aureus and E. coli were equal at approximately 0.29 mg/mL and considerably lower than those in gallic acid solution. Furthermore, the GACNP-loaded hydrogel patches demonstrated an attractive photodynamic effect against S. aureus, and it was superior to that of Ag hydrofiber®, a commercial material. Therefore, the photodynamic properties of GACNPs can be potentially used in the development of antibacterial hydrogels for wound healing applications.

Green synthesis of silver nanoparticles and its environmental sensor ability to some heavy metals

This study marks a pioneering effort in utilizing Vachellia tortilis subsp. raddiana (Savi) Kyal. & Boatwr., (commonly known as acacia raddiana) leaves as both a reducing and stabilizing agent in the green "eco-friendly" synthesis of silver nanoparticles (AgNPs). The research aimed to optimize the AgNPs synthesis process by investigating the influence of pH, temperature, extract volume, and contact time on both the reaction rate and the resulting AgNPs' morphology as well as discuss the potential of AgNPs in detecting some heavy metals. Various characterization methods, such as UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR), Zeta sizer, EDAX, and transmitting electron microscopy (TEM), were used to thoroughly analyze the properties of the synthesized AgNPs. The XRD results verified the successful production of AgNPs with a crystallite size between 20 to 30 nm. SEM and TEM analyses revealed that the AgNPs are primarily spherical and rod-shaped, with sizes ranging from 8 to 41 nm. Significantly, the synthesis rate of AgNPs was notably higher in basic conditions (pH 10) at 70 °C. These results underscore the effectiveness of acacia raddiana as a source for sustainable AgNPs synthesis. The study also examined the AgNPs' ability to detect various heavy metal ions colorimetrically, including Hg2+, Cu2+, Pb2+, and Co2+. UV-Vis spectroscopy proved useful for this purpose. The color of AgNPs shifts from brownish-yellow to pale yellow, colorless, pale red, and reddish yellow when detecting Cu2+, Hg2+, Co2+, and Pb2+ ions, respectively. This change results in an alteration of the AgNPs' absorbance band, vanishing with Hg2+ and shifting from 423 to 352 nm, 438 nm, and 429 nm for Cu2+, Co2+, and Pb2+ ions, respectively. The AgNPs showed high sensitivity, with detection limits of 1.322 × 10-5 M, 1.37 × 10-7 M, 1.63 × 10-5 M, and 1.34 × 10-4 M for Hg2+, Cu2+, Pb2+, and Co2+, respectively. This study highlights the potential of using acacia raddiana for the eco-friendly synthesis of AgNPs and their effectiveness as environmental sensors for heavy metals, showcasing strong capabilities in colorimetric detection.

Spotlight on therapeutic efficiency of green synthesis metals and their oxide nanoparticles in periodontitis

Periodontitis, one of the most prevalent dental diseases, causes the loss of bone and gum tissue that hold teeth in place. Several bacteria, commonly present in clinically healthy oral cavities, may induce and perpetuate periodontitis when their concentration rises in the gingival sulcus. Antibacterial effect against various Gram-negative and Gram-positive bacteria, including pathogenic and drug-resistant ones, has been shown for several distinct transient metal and metal oxide NPs. Therefore, NPs may be used in biomedicine to treat periodontal problems and in nanotechnology to inhibit the development of microorganisms. Instead of using harmful chemicals or energy-intensive machinery, biosynthesis of metal and metal oxide nanoparticles (NPs) has been suggested. To produce metal and metal oxide NPs, the ideal technique is "Green" synthesis because of its low toxicity and safety for human health and the environment. Gold NPs (AuNPs) appear to be less toxic to mammalian cells than other nanometals because their antibacterial activity is not dependent on reactive oxygen species (ROS). AgNPs also possess chemical stability, catalytic activity, and superior electrical and thermal conductivity, to name a few of their other advantageous characteristics. It was observed that zinc oxide (ZnO) NPs and copper (Cu) NPs exhibited discernible inhibitory effects against gram-positive and gram-negative bacterial strains, respectively. ZnO NPs demonstrated bactericidal activity against the microorganisms responsible for periodontitis. Medications containing magnetic NPs are highly effective against multidrug-resistant bacterial and fungal infections. The titanium dioxide (TiO2) NPs are implicated in elevating salivary peroxidase activity in individuals diagnosed with chronic periodontitis. Furthermore, specific metallic NPs have the potential to enhance the antimicrobial efficacy of periodontitis treatments when combined. Therefore, these NPs, as well as their oxide NPs, are only some of the metals and metal oxides that have been synthesized in environmentally friendly ways and shown to have therapeutic benefits against periodontitis.

Ionome mapping and amino acid metabolome profiling of Phaseolus vulgaris L. seeds imbibed with computationally informed phytoengineered copper sulphide nanoparticles

This study reports the effects of a computationally informed and avocado-seed mediated Phyto engineered CuS nanoparticles as fertilizing agent on the ionome and amino acid metabolome of Pinto bean seeds using both bench top and ion beam analytical techniques. Physico-chemical analysis of the Phyto engineered nanoparticles with scanning-electron microscopy, transmission electron microscopy, X-ray diffraction, and Fourier Transform Infrared Spectroscopy confirmed the presence of CuS nanoparticles. Molecular dynamics simulations to investigate the interaction of some active phytocompounds in avocado seeds that act as reducing agents with the nano-digenite further showed that 4-hydroxybenzoic acid had a higher affinity for interacting with the nanoparticle's surface than other active compounds. Seeds treated with the digenite nanoparticles exhibited a unique ionome distribution pattern as determined with external beam proton-induced X-ray emission, with hotspots of Cu and S appearing in the hilum and micropyle area that indicated a possible uptake mechanism via the seed coat. The nano-digenite also triggered a plant stress response by slightly altering seed amino acid metabolism. Ultimately, the nano-digenite may have important implications as a seed protective or nutritive agent as advised by its unique distribution pattern and effect on amino acid metabolism.

Applications of Green Synthesized Metal Nanoparticles - a Review

Green nanotechnology is an emerging field of science that focuses on the production of nanoparticles by living cells through biological pathways. This topic plays an extremely imperative responsibility in various fields, including pharmaceuticals, nuclear energy, fuel and energy, electronics, and bioengineering. Biological processes by green synthesis tools are more suitable to develop nanoparticles ranging from 1 to 100 nm compared to other related methods, owing to their safety, eco-friendliness, non-toxicity, and cost-effectiveness. In particular, the metal nanoparticles are synthesized by top-down and bottom-up approaches through various techniques like physical, chemical, and biological methods. Their characterization is very vital and the confirmation of nanoparticle traits is done by various instrumentation analyses such as UV-Vis spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), annular dark-field imaging (HAADF), and intracranial pressure (ICP). In this review, we provide especially information on green synthesized metal nanoparticles, which are helpful to improve biomedical and environmental applications. In particular, the methods and conditions of plant-based synthesis, characterization techniques, and applications of green silver, gold, iron, selenium, and copper nanoparticles are overviewed.

A new vision of photothermal therapy assisted with gold nanorods for the treatment of mammary cancers in adult female rats

Over the past decade, the therapeutic landscape has markedly changed for patients with breast cancers (BCs), yet few studies have evaluated the power of the photothermal therapy (PTT) technique. The present study aimed to assess the potency of 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary cancer treatment with this technique. In total, forty-two adult virgin female Wistar rats were categorized into seven groups, negative control, polyvinylpyrrolidone-capped gold nanorods (PVP-AuNRs) positive control (400 μL per rat ∼ 78 ppm), NIR laser irradiation 808 nm positive control with an intensity of (808 nm NIR CW diode laser, 200 mW cm-2 for 5 min), DMBA-treatment, DMBA-induced mammary cancer group treated with polyvinylpyrrolidone-capped gold nanorods, DMBA-induced mammary cancer group treated with NIR laser irradiation, and DMBA-induced mammary cancer group treated with polyvinylpyrrolidone-capped gold nanorods and NIR laser irradiation. Treatment with polyvinylpyrrolidone-capped gold nanorods and/or NIR laser irradiation was performed after three weeks of DMBA-induced mammary cancer. The mammary tumor lesions in the rat model induced with DMBA are highly invasive. Synthesis and characterization of gold nanorods (AuNRs) with an aspect ratio ranging from 2.8 to 3 were employed to validate the nanostructure and polyvinylpyrrolidone capping and their stability in absorbing near-infrared light. As a result, the therapy strategy, DMBA + PVP-AuNRs + NIR, effectively treated the tumor and halted its growth. The mammary glands were dissected and subjected to biochemical analysis for serum and tissue. Our treatment technique improved the histological aspects of mammary cancer in various forms of mammary cancer detected. Immuno-histochemical localization and TEM images supported these results reflecting the efficacy of this technique. Finally, our findings uncover for the first time the revolutionary effect of the PTT strategy using PVP-capped AuNRs in selectively destroying mammary cancer cells in rats.

Malus baccata (Linn.) Borkh polyphenols-loaded nanoparticles ameliorate intestinal health by modulating intestinal function and gut microbiota

The aim of this study was to construct the nanoparticles based on Hohenbuehelia serotina polysaccharides and mucin for encapsulation of the polyphenols from Malus baccata (Linn.) Borkh (MBP-MC-HSP NPs), and investigate their effects on intestinal function and gut microbiota in mice. The results showed that MBP-MC-HSP NPs did not have any toxic and side effect by determining organ indexes and hematological parameters. The colonic index, colonic length as well as colonic histology were significantly improved by treatment of MBP-MC-HSP NPs. Moreover, MBP-MC-HSP NPs could increase the fecal moisture (84.71 %) and accelerate the intestinal peristalsis (77.87 %), thus reducing the defecation time (1.68 h) of mice at certain extent. Through production of acetic acid, propionic acid and n-butyric acid, MBP-MC-HSP NPs remarkably decreased the pH of colonic feces to maintain intestinal health. 16S rRNA sequencing analysis showed that MBP-MC-HSP NPs could improve the abundances of Lactobacillus, Butyicicoccus and Ruminococcus and suppress the richness of Prevotella, Bifidobacterium and Desulfovibrio, thereby optimizing the structure and composition of gut microbiota. Furthermore, the metabolic profiles of gut microbiota were influenced by MBP-MC-HSP NPs based on prediction of KEGG and COG databases. Overall, this study suggests that MBP-MC-HSP NPs can be developed and utilized as probiotics in the nutritional food field.

Enhancing Visible-Light Photocatalysis with Pd(II) Porphyrin-Based TiO2 Hybrid Nanomaterials: Preparation, Characterization, ROS Generation, and Photocatalytic Activity

Novel hybrid TiO2-based materials were obtained by adsorption of two different porphyrins on the surface of nanoparticles-commercially available 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and properly modified metalloporphyrin-5,10,15,20-tetrakis(2,6-difluoro-3-sulfophenyl)porphyrin palladium(II) (PdF2POH). The immobilization of porphyrins on the surface of TiO2 was possible due to the presence of sulfonyl groups. To further elevate the adsorption of porphyrin, an anchoring linker-4-hydroxybenzoic acid (PHBA)-was used. The synthesis of hybrid materials was proven by electronic absorption spectroscopy, dynamic light scattering (DLS), and photoelectrochemistry. Results prove the successful photosensitization of TiO2 to visible light by both porphyrins. However, the presence of the palladium ion in the modifier structure played a key role in strong adsorption, enhanced charge separation, and thus effective photosensitization. The incorporation of halogenated metalloporphyrins into TiO2 facilitates the enhancement of the comprehensive characteristics of the investigated materials and enables the evaluation of their performance under visible light. The effectiveness of reactive oxygen species (ROS) generation was also determined. Porphyrin-based materials with the addition of PHBA seemed to generate ROS more effectively than other composites. Interestingly, modifications influenced the generation of singlet oxygen for TPPS but not hydroxyl radical, in contrast to PdF2POH, where singlet oxygen generation was not influenced but hydroxyl radical generation was increased. Palladium (II) porphyrin-modified materials were characterized by higher photostability than TPPS-based nanostructures, as TPPS@PHBA-P25 materials showed the highest singlet oxygen generation and may be oxidized during light exposure. Photocatalytic activity tests with two model pollutants-methylene blue (MB) and the opioid drug tramadol (TRML)-confirmed the light dose-dependent degradation of those two compounds, especially PdF2POH@P25, which led to the virtually complete degradation of MB.

Green synthesis, characterization, antibacterial, and antifungal activity of copper oxide nanoparticles derived from Morinda citrifolia leaf extract

The green methodologies of nanoparticles with plant extracts have received an increase of interest. Copper oxide nanoparticles (CuO NPs) have been utilized in a many of applications in the last few decades. The current study presents the synthesis of CuO NPs with aqueous extract of Morinda citrifolia as a stabilizing agent. The leaf extract of Morinda citrifolia was mixed with a solution of copper sulphate (CuSO4·5H2O) and sodium hydroxide as a catalyst. UV-visible spectroscopy, FTIR, XRD, SEM, TEM, and EDAX analysis were performed to study the synthesized CuO NPs. Particle size distribution of the synthesized CuO NPs have been measured with dynamic light scattering. The CuO NPs synthesized were highly stable, sphere-like, and have size of particles from 20 to 50 nm. Furthermore, as-formed CuO NPs shown strong antibacterial activity against the Gram-positive bacteria (Bacillus subtilis, and Staphylococcus aureus), and Gram-negative bacteria (Escherichia coli). CuO NPs revealed a similar trend was analysed for antifungal activity. The zone of inhibition for the fungi evaluated for Aspergillus flavus (13.0 ± 1.1), Aspergillus niger (14.3 ± 0.7), and Penicillium frequentans (16.8 ± 1.4). According to the results of this investigation, green synthesized CuO NPs with Morinda citrifolia leaf extract may be used in biomedicine as a replacement agent for biological applications.

Evaluation of antibacterial activity, in-vitro cytotoxicity and catalytic activity of biologically synthesized silver nanoparticles using leaf extracts of Leea macrophylla

Nanotechnology has become a cutting-edge field of research that has emerged as an interdisciplinary research area and contributes to almost every field of science. With the increasing demand for sustainable greener products, attention has recently been focused on green nanotechnology. This study manifested the aptitude of Leea macrophylla (LM) leaf extract, fortified with phytochemicals, to biosynthesize silver nanoparticles (AgNPs) for the first time. As soon as the AgNPs were biosynthesized, they immediately changed color, and the distinctive surface plasmon resonance (SPR) occurred at 420 nm in the Ultraviolet-Visible spectrum, proving that the biosynthesis had been successful. Fourier Transform Infrared Spectroscopy (FTIR) was used to examine the phytochemicals present in the LM leaf extract, those are accountable for the formation and stabilization of AgNPs. The Transmission Electron Microscope (TEM) revealed the formation of quasi spherical silver nanoparticles with an average diameter of 22.77 nm. Synthesized nanoparticles were further characterized by X-ray diffraction (XRD), Field Emission Scanning Electron microscope (FESEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS) and Thermogravimetric analysis (TGA). The production of AgNPs with high metal content from LM leaf extract exhibited encouraging results. The LM leaf extract mediated silver nanoparticles evinced significant antibacterial and catalytic activities. The cytotoxicity effects of biosynthesized AgNPs were tested on brine shrimps.

Facile green synthesis and characterization of Terminalia arjuna bark phenolic-selenium nanogel: a biocompatible and green nano-biomaterial for multifaceted biological applications

Biogenic nanoparticle production is in demand as it is secure, has great promise, and is environmental friendly. This study aimed at green synthesis, characterization, and evaluation of Terminalia arjuna selenium nanoparticles (TA-SeNPs) for their antioxidant, antibacterial, anticancer activities, and their incorporation in gel for biomedical applications. The bio-reduction attributes of the T. arjuna (TA) bark extract were utilized to fabricate selenium nanoparticles. The TA bark extract is abundant in phenolics (193.63 ± 1.61 mg gallic acid equivalents/g), flavonoids (88.23 ± 0.39 mg quercetin equivalents/g), and tannins (109.46 ± 1.16 mg catechin equivalents/g), which perform as effective capping and stabilizing agents, thus enabling the fabrication of stable SeNPs. The fabrication of TA-SeNPs was corroborated by UV-visible spectra, which exhibited surface plasmon resonance at 291 nm. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) demonstrated nano-sized spherical TA-SeNPs with an average diameter ranging from 100 to 150 nm. Zeta potential analysis revealed that TA-SeNPs were negatively charged (-26.1 mV). X-ray diffraction presented amorphous TA-SeNPs with a quantification of 82.36 ± 10.2 μg/mL resulting from ICP-AES. The IC50 45.18 ± 0.11 μg/mL for the DPPH assay and 66.51% reducing power capacity values indicated that the TA-SeNPs possessed excellent radical scavenging efficacy. Moreover, the TA-SeNPs exhibited a broad spectrum of antimicrobial activity against potential pathogens. Additionally, the TA-SeNPs exhibited a dose-dependent cytotoxic effect on the MCF-7 breast cancer cell line, with an IC50 of 23.41 μg/mL. Furthermore, the TA-SeNP-incorporated gel showed excellent spreadability, extrudability, and consistency with retention of antimicrobial properties and hydrophilic contact angle. As an outcome, TA-SeNPs offer the possibility of the formulation and growth of sustainably designed green SeNPs that can be produced, conserved, and marketed securely across the globe.

Green synthesized silver nanoparticles mediated by Fusarium nygamai isolate AJTYC1: characterizations, antioxidant, antimicrobial, anticancer, and photocatalytic activities and cytogenetic effects

Green biosynthesized nanoparticles have a bright future because they can be produced using a method that is more energy-efficient, cost-effective, repeatable, and environmentally friendly than physical or chemical synthesis. In this study, silver nanoparticles (AgNPs) were produced using the Fusarium nygamai isolate AJTYC1. Several techniques were used to characterize the synthesized AgNPs, including UV-Vis spectroscopy, transmission electron microscope, zeta potential analysis, X-ray diffraction analysis, energy dispersive X-ray, and Fourier transform-infrared spectroscopy. AgNPs showed a distinctive surface plasmon resonance (SPR) peak in the UV-visible range at 310 nm. The morphology of the biosynthesized AgNPs was spherical, and the TEM image shows that they ranged in size from 27.3 to 53.1 nm. The notable peaks of the FT-IR results show the different groups for the alkane, alkynes, cyclic alkenes, carboxylic, aromatic amine, esters, and phenolics. Additionally, the results showed that AgNPs had superior antioxidant activity when compared to ascorbic acid and butylated hydroxytoluene, which is a powerful antioxidant. Additionally, AgNPs have antibacterial action utilizing agar diffusion against gram-positive bacteria, gram-negative bacteria, and antifungal activity. AgNPs' anticancer activity varied depending on the type of cancer it was used to treat, including hepatocellular cancer (HepG2), colorectal carcinoma (HCT116), and breast cancer of the mammary gland (MCF7). The viability of the cancer cell lines was reduced with increasing AgNP concentration. AgNPs also demonstrated promising photocatalytic activity by reducing methylene blue, safranin, crystal violet, and green malachite by 88.3%, 81.5%, 76.4%, and 78.2%, respectively. In addition, AgNPs significantly affected the Allium cepa plant's mitotic index and resulted in chromosomal abnormalities as compared to the control. Thus, the synthesized AgNPs demonstrated an efficient, eco-friendly, and sustainable method for decolorizing dyes as well as antioxidant, antibacterial, antifungal, and anticancer activities. This could be a huge victory in the fight against numerous dynamic diseases and lessen wastewater dye contamination.

Nano-stevia interaction: Past, present, and future

Nanotechnology has recently been emerged as a transformative technology that offers efficient and sustainable options for nano-bio interface. There has been a considerable interest in exploring the factors affecting elicitation mechanism and nanomaterials have been emerged as strong elicitors in medicinal plants. Stevia rebaudiana is well-known bio-sweetener and the presence of zero calorie, steviol glycosides (SGs) in the leaves of S. rebaudiana have made it a desirable crop to be cultivated on large scale to obtain its higher yield and maximal content of high quality natural sweeteners. Besides, phenolics, flavonoids, and antioxidants are abundant in stevia which contribute to its medicinal importance. Currently, scientists are trying to increase the market value of stevia by the enhancement in production of its bioactive compounds. As such, various in vitro and cell culture strategies have been adopted. In stevia agronanotechnology, nanoparticles behave as elicitors for the triggering of its secondary metabolites, specifically rebaudioside A. This review article discusses the importance of S. rebaudiana and SGs, conventional approaches that have failed to increase the desired yield and quality of stevia, modern approaches that are currently being applied to obtain utmost benefits of SGs, and future needs of advanced technologies for further exploitation of this wonder of nature.

Biosynthesis of Silver Nanoparticles Functionalized with Histidine and Phenylalanine Amino Acids for Potential Antioxidant and Antibacterial Activities

Due to biochemically active secondary metabolites that assist in the reduction, stabilization, and capping of nanoparticles, plant-mediated nanoparticle synthesis is becoming more and more popular. This is because it allows for ecologically friendly, feasible, sustainable, and cost-effective green synthesis techniques. This study describes the biosynthesis of silver nanoparticles (AgNPs) functionalized with histidine and phenylalanine using the Lippia abyssinica (locally called koseret) plant leaf extract. The functionalization with amino acids was meant to enhance the biological activities of the AgNPs. The synthesized nanoparticles were characterized using UV-Visible absorption (UV-Vis), powder X-ray diffraction (pXRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. The surface plasmonic resonance (SPR) peak at about 433 nm confirmed the biosynthesis of the AgNPs. FTIR spectra also revealed that the phytochemicals in the plant extract were responsible for the capping of the biogenically synthesized AgNPs. On the other hand, the TEM micrograph revealed that the morphology of AgNP-His had diameters ranging from 5 to 14 nm. The antibacterial activities of the synthesized nanoparticles against Gram-positive and Gram-negative bacteria showed a growth inhibition of 8.67 ± 1.25 and 11.00 ± 0.82 mm against Escherichia coli and Staphylococcus aureus, respectively, at a concentration of 62.5 μg/mL AgNP-His. Moreover, the nanoparticle has an antioxidant activity potential of 63.76 ± 1.25% at 250 μg/mL. The results showed that the green-synthesized AgNPs possess promising antioxidant and antibacterial activities with the potential for biological applications.

Evaluation of Cytotoxicity, Release Behavior and Phytopathogens Control by Mancozeb-Loaded Guar Gum Nanoemulsions for Sustainable Agriculture

Chemical fungicides are the backbone of modern agriculture, but an alternative formulation is necessary for sustainable crop production to address human health issues and soil/water environmental pollution. So, a green chemistry approach was used to form guar gum nanoemulsions (NEs) of 186.5-394.1 nm containing the chemical fungicide mancozeb and was characterized using various physio-chemical techniques. An 84.5% inhibition was shown by 1.5 mg/mL mancozeb-loaded NEs (GG-1.5) against A. alternata, comparable to commercial mancozeb (86.5 ± 0.7%). The highest mycelial inhibition was exhibited against S. lycopersici and S. sclerotiorum. In tomatoes and potatoes, NEs showed superior antifungal efficacy in pot conditions besides plant growth parameters (germination percentage, root/shoot ratio and dry biomass). About 98% of the commercial mancozeb was released in just two h, while only about 43% of mancozeb was released from nanoemulsions (0.5, 1.0 and 1.5) for the same time. The most significant results for cell viability were seen at 1.0 mg/mL concentration of treatment, where wide gaps in cell viability were observed for commercial mancozeb (21.67%) and NEs treatments (63.83-71.88%). Thus, this study may help to combat the soil and water pollution menace of harmful chemical pesticides besides protecting vegetable crops.

A review on the green synthesis of nanoparticles, their biological applications, and photocatalytic efficiency against environmental toxins

Green synthesis of nanoparticles (NPs) using plant materials and microorganisms has evolved as a sustainable alternative to conventional techniques that rely on toxic chemicals. Recently, green-synthesized eco-friendly NPs have attracted interest for their potential use in various biological applications. Several studies have demonstrated that green-synthesized NPs are beneficial in multiple medicinal applications, including cancer treatment, targeted drug delivery, and wound healing. Additionally, due to their photodegradation activity, green-synthesized NPs are a promising tool in environmental remediation. Photodegradation is a process that uses light and a photocatalyst to turn a pollutant into a harmless product. Green NPs have been found efficient in degrading pollutants such as dyes, herbicides, and heavy metals. The use of microbes and flora in green synthesis technology for nanoparticle synthesis is biologically safe, cost-effective, and eco-friendly. Plants and microbes can now use and accumulate inorganic metallic ions in the environment. Various NPs have been synthesized via the bio-reduction of biological entities or their extracts. There are several biological and environmental uses for biologically synthesized metallic NPs, such as photocatalysis, adsorption, and water purification. Since the last decade, the green synthesis of NPs has gained significant interest in the scientific community. Therefore, there is a need for a review that serves as a one-stop resource that points to relevant and recent studies on the green synthesis of NPs and their biological and photocatalytic efficiency. This review focuses on the green fabrication of NPs utilizing diverse biological systems and their applications in biological and photodegradation processes.

Myco-Synthesis of Silver Nanoparticles and Their Bioactive Role against Pathogenic Microbes

Nanotechnology based on nanoscale materials is rapidly being used in clinical settings, particularly as a new approach for infectious illnesses. Recently, many physical/chemical approaches utilized to produce nanoparticles are expensive and highly unsafe to biological species and ecosystems. This study demonstrated an environmentally friendly mode of producing nanoparticles (NPs) where Fusarium oxysporum has been employed for generation of silver nanoparticles (AgNPs), which were further tested for their antimicrobial potentials against a variety of pathogenic microorganisms. The characterization of NPs was completed by UV-Vis spectroscopy, DLS and TEM, where it has been found that the NPs were mostly globular, with the size range of 50 to 100 nm. The myco-synthesized AgNPs showed prominent antibacterial potency observed as zone of inhibition of 2.6 mm, 1.8 mm, 1.5 mm, and 1.8 mm against Vibrio cholerae, Streptococcus pneumoniae, Klebsiella pneumoniae and Bacillus anthracis, respectively, at 100 µM. Similarly, at 200 µM for A. alternata, A. flavus and Trichoderma have shown zone of inhibition as 2.6 mm, 2.4 mm, and 2.1 mm, respectively. Moreover, SEM analysis of A. alternata confirmed the hyphal damage where the layers of membranes were torn off, and further EDX data analysis showed the presence of silver NPs, which might be responsible for hyphal damage. The potency of NPs may be related with the capping of fungal proteins that are produced extracellularly. Thus, these AgNPs may be used against pathogenic microbes and play a beneficial role against multi-drug resistance.

Sericin mediated gold/silver bimetallic nanoparticles and exploration of its multi-therapeutic efficiency and photocatalytic degradation potential

The current investigation aimed at bimetallic gold-silver nanoparticles (Au/Ag NPs), here called BM-GS NPs, synthesis using sericin protein as the reducing agent in an easy, cost-effective, and sustainable way. The obtained BM-GS NPs were characterized by UV-Visible spectroscopy, Transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS), atomic force microscopy (AFM), Dynamic light scattering (DLS) and Zeta potential, X-ray Powder Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and Thermogravimetric analysis followed by evaluation of its multitherapeutic and photocatalytic degradation potentials. The TEM analysis revealed its spherical nature and the EDS result displayed the presence of both Ag and Au elements, confirming the synthesis of BM-GS NPs. The XRD pattern verified the crystalline nature of the nanoparticles (NPs). The DLS analysis showed an average size of 86.08 d nm and the zeta potential showed a highly negative value (-26.3 mV) which specifies that the generated bimetallic NPs are stable. The BM-GS NPs exhibited positive wound healing potential (with 63.38% of wound closure rate at 25 μg/ml, as compared to 54.42% by the untreated control) with very negligible toxicity effect on the cell viability of the normal keratinocyte cells. It also demonstrated promising antioxidant properties with 65.00%, 69.23%, and 63.03% activity at 100 μg/ml concentration for ABTS (2, 2-azinobis) (3-ethylbenzothiazoline-6-sulfonic acid)), DPPH (1, 1 diphenyl-2-picrylhydrazyl) and SOD (superoxide dismutase enzyme) assays respectively, antidiabetic potential (with a significantly high α-glucosidase inhibition potential of 99.69% at 10μg/ml concentration and 62.11% of α-amylase enzyme inhibition at 100 μg/ml concentration) and moderate tyrosinase inhibitory potential (with 17.09% at 100 μg/ml concentration). Besides, it displayed reasonable antibacterial potential with the diameter of zone of inhibition ranging between 10.89 and 12.39 mm. Further, its antibacterial mode of action reveals that its effects could be due to being very smaller, the NPs could have penetrated inside the cellular membrane thereby causing rupture and damage to the interior materials leading to cellular lysis. The photocatalytic evaluation showed that synthesized BM-GS NPs have the efficiency of degrading methylene blue dye by 34.70% within 3 h of treatment. The above findings revealed the multi-therapeutic efficacy of the sericin globular protein-mediated BM-GS NPs and its potential future applications in the cosmetics and food sector and environmental contamination management industries.

Green Biogenic of Silver Nanoparticles Using Polyphenolic Extract of Olive Leaf Wastes with Focus on Their Anticancer and Antimicrobial Activities

Agro-industrial wastes are rich in polyphenols and other bioactive compounds, and valorizing these wastes is a crucial worldwide concern for saving health and the environment. In this work, olive leaf waste was valorized by silver nitrate to produce silver nanoparticles (OLAgNPs), which exhibited various biological, antioxidant, anticancer activities against three cancer cell lines, and antimicrobial activity against multi-drug resistant (MDR) bacteria and fungi. The obtained OLAgNPs were spherical, with an average size of 28 nm, negatively charged at -21 mV, and surrounded by various active groups more than the parent extract based on FTIR spectra. The total phenolic and total flavonoid contents significantly increased in OLAgNPs by 42 and 50% over the olive leaf waste extract (OLWE); consequently, the antioxidant activity of OLAgNPs increased by 12% over OLWE, recording an SC₅₀ of OLAgNPs of 5 µg/mL compared to 30 µg/mL in the extract. The phenolic compound profile detected by HPLC showed that gallic acid, chlorogenic acid, rutin, naringenin, catechin, and propyl gallate were the main compounds in the HPLC profile of OLAgNPs and OLWE; the content of these compounds was higher in OLAgNPs than OLWE by 16-fold. The higher phenolic compounds in OLAgNPs are attributable to the significant increase in biological activities of OLAgNPs than that of OLWE. OLAgNPs successfully inhibited the proliferation of three cancer cell lines, MCF-7, HeLa, and HT-29, by 79-82% compared to 55-67% in OLWE and 75-79% in doxorubicin (DOX). The preliminary worldwide problem is multi-drug resistant microorganisms (MDR) because of the random use of antibiotics. Therefore, in this study, we may find the solution in OLAgNPs with concentrations of 2.5-20 µg/mL, which significantly inhibited the growth of six MDR bacteria L. monocytogenes, B. cereus, S. aureus, Y. enterocolitica, C. jejuni, and E. coli with inhibition zone diameters of 25-37 mm and six pathogenic fungi in the range of 26-35 mm compared to antibiotics. OLAgNPs in this study may be applied safely in new medicine to mitigate free radicals, cancer, and MDR pathogens.

Inhibition of Biofilm and Virulence Properties of Pathogenic Bacteria by Silver and Gold Nanoparticles Synthesized from Lactiplantibacillus sp. Strain C1

The emergence of antibiotic resistance in microbial pathogens necessitates the development of alternative ways to combat the infections that arise. The current study used nanotechnology as an alternate technique to control virulence characteristics and biofilm development in Pseudomonas aeruginosa and Staphylococcus aureus. Furthermore, based on the acceptance and biocompatibility of the probiotic bacteria, we chose a lactic acid bacteria (LAB) for synthesizing two types of metallic nanoparticles (NPs) in this study. Using molecular techniques, the LAB strain C1 was isolated from Kimchi food samples and identified as Lactiplantibacillus sp. strain C1. The prepared supernatant from strain C1 was used to produce gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs). C1-AuNPs and C1-AgNPs were characterized physiochemically using a variety of instruments. C1-AuNPs and C1-AgNPs had spherical shapes and sizes of 100.54 ± 14.07 nm (AuNPs) and 129.51 ± 12.31 nm (AgNPs), respectively. C1-AuNPs and C1-AgNPs were discovered to have high zeta potentials of -23.29 ± 1.17 and -30.57 ± 0.29 mV, respectively. These nanoparticles have antibacterial properties against several bacterial pathogens. C1-AuNPs and C1-AgNPs significantly inhibited the initial stage biofilm formation and effectively eradicated established mature biofilms of P. aeruginosa and S. aureus. Furthermore, when P. aeruginosa was treated with sub-MIC levels of C1-AuNPs and C1-AgNPs, their different virulence features were significantly reduced. Both NPs greatly inhibited the hemolytic activity of S. aureus. The inhibition of P. aeruginosa and S. aureus biofilms and virulence features by C1-AuNPs and C1-AgNPs can be regarded as viable therapeutic strategies for preventing infections caused by these bacteria.

Myco-Nanofabrication of Silver Nanoparticles by Penicillium brasilianum NP5 and Their Antimicrobial, Photoprotective and Anticancer Effect on MDA-MB-231 Breast Cancer Cell Line

Currently, the exploration of fungal organisms for novel metabolite production and its pharmacological applications is much appreciated in the biomedical field. In the present study, the fungal strains were isolated from soil of unexplored Yellapura regions. The potent isolate NP5 was selected based on preliminary screening and identified as Penicillium brasilianum NP5 through morphological, microscopic, and molecular characterizations. Synthesis of silver nanoparticles from P. brasilianum was confirmed by the color change of the reaction mixture and UV-visible surface plasmon resonance (SPR) spectra of 420 nm. Fourier transform infrared (FTIR) analysis revealed the functional groups involved in synthesis. Atomic force microscopy (AFM) and transmission electron microscope (TEM) analysis showed aggregation of the NPs, with sizes ranged from 10 to 60 nm, an average particle size of 25.32 nm, and a polydispersity index (PDI) of 0.40. The crystalline nature and silver as the major element in NP5-AgNPs was confirmed by X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis. The negative value −15.3 mV in Zeta potential exhibited good stability, and thermostability was recorded by thermogravimetric analysis (TGA). NP5-AgNPs showed good antimicrobial activity on selected human pathogens in a concentration-dependent manner. The MTT assay showed concentration-dependent anticancer activity with an IC50 of 41.93 µg/mL on the MDA-MB-231 cell line. Further, apoptotic study was carried out by flow cytometry to observe the rate of apoptosis. The calculated sun protection factor (SPF) value confirms good photoprotection capacity. From the results obtained, NP5-AgNPs can be used in the pharmaceutical field after successful in vitro clinical studies.

Alnus nitida and urea-doped Alnus nitida-based silver nanoparticles synthesis, characterization, their effects on the biomass and elicitation of secondary metabolites in wheat seeds under in vitro conditions

Nano-fertilizers are superior to conventional fertilizers, but their effectiveness has not yet been adequately explored in the field of agriculture. In this study, silver nanoparticles using leaves extract of an Alnus nitida plant were synthesized and further doped with urea to enhance the plant biomass and metabolic contents. The synthesized Alnus nitida silver nanoparticles (A.N-AgNPs) and urea-doped silver nanoparticles (U-AgNPs) were characterized using Scanning Electron Microscopy, Transmission Electron Microscopy, Powder X-ray Diffraction, and Energy Dispersive X-ray. The wheat seeds were grown in media under controlled conditions in the plant growth chamber. The effectiveness of nanoparticles was studied using different A.N-AgNPs and U-AgNPs concentrations (0.75 μg/ml, 1.5 μg/ml, 3 μg/ml, 6 μg/ml, and 15 μg/ml). They were compared with a control group that received no dose of nanoparticles. The plant biomass, yield parameters, and wheat quality were analyzed. The effect of silver nanoparticles and U-AgNPs were examined in developing wheat seeds and their potency in combating biotic stresses such as nematodes, herbivores, fungi, insects, weeds and bacteria; abiotic stresses such as salinity, ultraviolet radiation, heavy metals, temperature, drought, floods etc. In the seedlings, six possible phytochemicals at a spray dose of 6 μg/ml of U-AgNPs were identified such as dihydroxybenzoic acids, vanillic acid, apigenin glucosidase, p-coumaric acid, sinapic acid, and ferulic acid whereas in other treatments the number of phenolic compounds was lesser in number as well as in concentrations. Moreover, various parameters of the wheat plants, including their dry weight and fresh weight, were assessed and compared with control group. The findings of the study indicated that A.N-AgNPs and U-AgNPs act as metabolite elicitors that induced secondary metabolite production (total phenolic, flavonoid, and chlorophyll contents). In addition, U-AgNPs provided a nitrogen source and were considered a smart nitrogen fertilizer that enhanced the plant biomass, yields, and metabolite production.

Bio-Fabrication of Trimetallic Nanoparticles and Their Applications

Nanoparticles are materials whose size is less than 100 nm. Because of their distinctive physical and chemical characteristics, nanoparticles have drawn considerable interest in a variety of fields. Biosynthesis of nanoparticles is a green and environmentally friendly technology, which requires fewer chemical reagents, precursors, and catalysts. There are various types of nanomaterials, out of which trimetallic nanoparticles are receiving considerable interest in recent years. Trimetallic nanoparticles possess unique catalytic, biomedical, antimicrobial, active food packaging, and sensing applications as compared to monometallic or bimetallic nanoparticles. Trimetallic nanoparticles are currently synthesized by various methods such as chemical reduction, microwave-assisted, thermal, precipitation, and so on. However, most of these chemical and physical methods are expensive and toxic to the environment. Biological synthesis is one of the promising methods, which includes the use of bacteria, plants, fungi, algae, waste biomass, etc., as reducing agents. Secondary metabolites present in the biological agents act as capping and reducing agents. Green trimetallic nanoparticles can be used for different applications such as anticancer, antibacterial, antifungal, catalytic activity, etc. This review provides an overview of the synthesis of trimetallic nanoparticles using biological agents, and their applications in different areas such as anticancer, antimicrobial activity, drug delivery, catalytic activity, etc. Finally, current challenges, future prospects, and conclusions are highlighted.

Activities against Lung Cancer of Biosynthesized Silver Nanoparticles: A Review

Nanomedicine is an interdisciplinary field where nanostructured objects are applied to treat or diagnose disease. Nanoparticles (NPs) are a special class of materials at nanometric scale that can be prepared from lipids, polymers, or noble metals through bottom-up approaches. Biological synthesis is a reliable, sustainable, and non-toxic bottom-up method that uses phytochemicals, microorganisms, and enzymes to induce the reduction of metal ions into NPs. Silver (Ag) NPs exhibit potent therapeutic properties that can be exploited to overcome the limitations of current treatment modalities for human health issues such as lung cancer (LC). Here, we review the preparation of AgNPs using biological synthesis and their application against LC using in vitro and in vivo models. An overview of the staging, diagnosis, genetic mutations, and treatment of LC, as well as its main subtypes, is presented. A summary of the reaction mechanisms of AgNPs using microbial cell cultures, plant extracts, phytochemicals, and amino acids is included. The use of capping agents in the biosynthesis of AgNPs with anticancer activity is also detailed. The history and biological activities of metal-based nanostructures synthesized with gold, copper, palladium, and platinum are considered. The possible anticancer mechanisms of AgNPs against LC models are covered. Our perspective about the future of AgNPs in LC treatment and nanomedicine is added.

Biogenic Selenium Nanoparticles in Biomedical Sciences: Properties, Current Trends, Novel Opportunities and Emerging Challenges in Theranostic Nanomedicine

Selenium is an important dietary supplement and an essential trace element incorporated into selenoproteins with growth-modulating properties and cytotoxic mechanisms of action. However, different compounds of selenium usually possess a narrow nutritional or therapeutic window with a low degree of absorption and delicate safety margins, depending on the dose and the chemical form in which they are provided to the organism. Hence, selenium nanoparticles (SeNPs) are emerging as a novel therapeutic and diagnostic platform with decreased toxicity and the capacity to enhance the biological properties of Se-based compounds. Consistent with the exciting possibilities offered by nanotechnology in the diagnosis, treatment, and prevention of diseases, SeNPs are useful tools in current biomedical research with exceptional benefits as potential therapeutics, with enhanced bioavailability, improved targeting, and effectiveness against oxidative stress and inflammation-mediated disorders. In view of the need for developing eco-friendly, inexpensive, simple, and high-throughput biomedical agents that can also ally with theranostic purposes and exhibit negligible side effects, biogenic SeNPs are receiving special attention. The present manuscript aims to be a reference in its kind by providing the readership with a thorough and comprehensive review that emphasizes the current, yet expanding, possibilities offered by biogenic SeNPs in the biomedical field and the promise they hold among selenium-derived products to, eventually, elicit future developments. First, the present review recalls the physiological importance of selenium as an oligo-element and introduces the unique biological, physicochemical, optoelectronic, and catalytic properties of Se nanomaterials. Then, it addresses the significance of nanosizing on pharmacological activity (pharmacokinetics and pharmacodynamics) and cellular interactions of SeNPs. Importantly, it discusses in detail the role of biosynthesized SeNPs as innovative theranostic agents for personalized nanomedicine-based therapies. Finally, this review explores the role of biogenic SeNPs in the ongoing context of the SARS-CoV-2 pandemic and presents key prospects in translational nanomedicine.

Bioremediation of Hazardous Wastes Using Green Synthesis of Nanoparticles

Advanced agronomic methods, urbanisation, and industrial expansion contaminate air, water and soil, globally. Agricultural and industrial activities threaten living biota, causing biodiversity loss and serious diseases. Strategies such as bioremediation and physiochemical remediation have not been effectively beneficial at treating pollutants. Metal-based nanoparticles (NPs) such as copper, zinc, silver, gold, etc., in various nanoformulations and nanocomposites are used more and more as they effectively resist the uptake of toxic compounds via plants by facilitating their immobilisation. According to studies, bio-based NP synthesis is a recent and agroecologically friendly approach for remediating environmental waste, which is effective against carcinogens, heavy metal contamination, treating marine water polluted with excessive concentrations of phosphorus, nitrogen and harmful algae, and hazardous dye- and pesticide-contaminated water. Biogenic resources such as bacteria, fungi, algae and plants are extensively used for the biosynthesis of NPs, particularly metallic NPs. Strategies involving green synthesis of NPs are nontoxic and could be employed for commercial scale production. Here, the focus is on the green synthesis of NPs for reduction of hazardous wastes to help with the clean-up process.

Polyol-mediated zinc oxide nanoparticles using the refluxing method as an efficient photocatalytic and antimicrobial agent

Nanomaterials have attracted more curiosity recently because of their wide-ranging application in environmental remediation and electronic devices. The current study focuses on zinc oxide nanoparticles' (ZnO NPs) simple production, characterization, and applications in several fields, including medicinal and photocatalytic degradation of dyes. The non-aqueous-based reflux method is helpful for ZnO NP synthesis; the procedure involves refluxing zinc acetate dihydrate precursor in ethylene glycol for 3 hours in the absence of sodium acetate, in which the refluxing rate and the cooling rate are optimized to get the desired phase, and the unique morphology of polyol-mediated ZnO NPs; it has been achieved using the capping agent TBAB (tetra-butyl ammonium bromide) and precursor zinc acetate dihydrate. UV-Vis, FTIR, XRD, and FESEM structurally characterized polyol-mediated ZnO-NPs. The results show that the material is pure and broadly aggregated into spherical nanoparticles with an average particle size of 18.09 nm. According to XRD analysis, heat annealing made the crystallites more prominent and favored a monocrystalline state. These results and the low cost of making polyol-mediated ZnO NPs demonstrate photocatalytic and antimicrobial properties.

Biofabrication of nanoparticles: sources, synthesis, and biomedical applications

Nanotechnology is an emerging applied science delivering crucial human interventions. Biogenic nanoparticles produced from natural sources have received attraction in recent times due to their positive attributes in both health and the environment. It is possible to produce nanoparticles using various microorganisms, plants, and marine sources. The bioreduction mechanism is generally employed for intra/extracellular synthesis of biogenic nanoparticles. Various biogenic sources have tremendous bioreduction potential, and capping agents impart stability. The obtained nanoparticles are typically characterized by conventional physical and chemical analysis techniques. Various process parameters, such as sources, ions, and temperature incubation periods, affect the production process. Unit operations such as filtration, purification, and drying play a role in the scale-up setup. Biogenic nanoparticles have extensive biomedical and healthcare applications. In this review, we summarized various sources, synthetic processes, and biomedical applications of metal nanoparticles produced by biogenic synthesis. We highlighted some of the patented inventions and their applications. The applications range from drug delivery to biosensing in various therapeutics and diagnostics. Although biogenic nanoparticles appear to be superior to their counterparts, the molecular mechanism degradation pathways, kinetics, and biodistribution are often missing in the published literature, and scientists should focus more on these aspects to move them from the bench side to clinics.

Apoptotic effects of Phlomis armeniaca mediated biosynthesized silver nanoparticles in monolayer (2D) and spheroid (3D) cultures of human breast cancer cell lines

The purpose of current research was to assess the apoptotic effects of biofabrication silver nanoparticles (AgNPs) mediated by the aqueous extract of Phlomis armeniaca on human breast cancer cells (MCF-7 and MDA-MB-231) in monolayer (2D) and spheroid (3D) cultures. The biosynthesized AgNPs were characterized by UV-Vis spectrophotometer (the peaks of resonances at 432 nm), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). 1-20 µM/mL AgNPs were applied to MCF-7 and MDA-MB-231 cell lines to determine IC50 values at 24, 48 and 72nd h and were found to be 10 µM/mL for both cell lines. Immunohistochemical staining results of BrdU, TUNEL, caspase-3 and Endo G in both 2D and 3D cultures and gene expression levels of caspases (caspase-3, -8 and -9) and Endo G were evaluated. Moreover, the total oxidant/antioxidant status (TOS-TAS) due to AgNPs application in both cell culture mediums was evaluated. AgNPs treatment results in both cell lines in both 2D and 3D cultures showed a significant decrease in the BrdU labeling index, while large amounts of cells were labelled with TUNEL and Endo G. In 2D culture, Endo G expression increased in MCF-7 cells at 48 and 72nd hours, while it increased significantly in MDA-MB-231 cells at all hours. OSI results show that ROS production is increased in cell medium treated with AgNPs. In conclusion, AgNPs mediated by Phlomis armeniaca, synthesized by a green method, successfully induced damage to mitochondria, resulting in cell cycle arrest and consequent cell proliferation blockade and death in both MCF-7 and MDA-MB-231 cells.

Green Synthesis and Characterization of Silver Nanoparticles Using Myrsine africana Leaf Extract for Their Antibacterial, Antioxidant and Phytotoxic Activities

Nanotechnology is the study and control of materials at length scales between 1 and 100 nanometers (nm), where incredible phenomena enable new applications. It affects all aspects of human life and is the most active research topic in modern materials science. Among the various metallic nanoparticles used in biomedical applications, silver nanoparticles (AgNPs) are among the most important and interesting nanomaterials. The aim of this study was to synthesize AgNPs from the leaf extract of Myrsine africana to investigate their antibacterial, antioxidant, and phytotoxic activities. When the leaf extract was treated with AgNO3, the color of the reaction solution changed from light brown to dark brown, indicating the formation of AgNPs. The UV-visible spectrum showed an absorption peak at 438 nm, confirming the synthesis of AgNPs. Scanning electron microscopy (SEM) showed that the AgNPs were spherical and oval with an average size of 28.32 nm. Fourier transform infrared spectroscopy confirms the presence of bio-compound functional groups on the surface of the AgNPs. The crystalline nature of the AgNPs was confirmed by XRD pattern. These biosynthesized AgNPs showed pronounced antibacterial activity against Gram-positive and Gram-negative bacteria, with higher inhibitory activity against Escherichia coli. At 40 µg/mL AgNPs, the highest antioxidant activity was obtained, which was 57.7% and an IC50 value of 77.56 µg/mL. A significant positive effect was observed on all morphological parameters when AgNPs were applied to wheat seedlings under constant external conditions at the different concentrations. The present study provides a cost-effective and environmentally friendly method for the synthesis of AgNPs, which can be effectively used in the field of therapeutics, as antimicrobial and diagnostic agents, and as plant growth promoters.