Synthesis and characterization comparison of peanut shell extract silver nanoparticles with commercial silver nanoparticles and their antifungal activity

Partial characterization of purified glycoprotein from nutshell of Arachis hypogea L. towards macrophage activation and leishmaniacidal activity

Arachis hypogea L. protein fraction-2 (AHP-F2) from the Peanut shell was extracted and characterized and its potent immunomodulatory and anti-leishmanial role was determined in this present study. AHP-F2 was found to be a glycoprotein as the presence of carbohydrates were confirmed by the analysis of high-performance liquid chromatography (HPLC) yielded glucose, galactose, mannose, and xylose. AHP-F2 molecular mass was found to be ∼28 kDa as indicated in MALDI-TOF and peptide mass fingerprinting analysis followed by Mascot search. The peptide matches revealed the similarity of the mannose/glucose binding lectin with 71.07% in the BLAST analysis. After that, the 3D structure of the AHP-F2 model was designed and validated by the Ramachandran plot. The immunomodulatory role of AHP-F2 was established in murine peritoneal macrophages as induction of nitric oxide (NO), and stimulation of proinflammatory cytokines (IL-12 and IFN-γ) in a dose-dependent manner was observed. Interestingly, it was also found that AHP-F2 has interacted with the innate immune receptor, toll-like receptors (TLRs) as established in molecular docking as well as mRNA expression. The anti-leishmanial potential of AHP-F2 was revealed with a prominent inhibition of amastigote growth within the murine macrophages with prompt induction of nitrite release. Altogether, the isolated AHP-F2 from Arachis hypogea L. has strong immunomodulatory and anti-leishmanial potential which may disclose a new path to treat leishmaniasis.

Comparative Bio-Potential Effects of Fresh and Boiled Mountain Vegetable (Fern) Extract Mediated Silver Nanoparticles

This current investigation was designed to synthesize Ag nanoparticles (AgNPs) using both the fresh (Fbf) and boiled (Bbf) Korean mountain vegetable fern (named Gosari) extracts and make a comparative evaluation of its multi-therapeutic potentials. The screening of phytochemicals in the fern extract was undertaken. The synthesized fern-mediated silver nanoparticles are characterized and investigated for their bio-potential like α-glucosidase inhibition, antioxidant, and cytotoxicity prospects. The obtained AgNPs were characterized by the UV-Vis Spectra, SEM, EDS, XRD, FTIR, DLS, Zeta potential analysis, etc. The synthesis of the Fbf-AgNPs was very fast and started within 1 h of the reaction whereas the synthesis of the Bbf-AgNPs synthesis was slow and it started around 18 h of incubation. The UV-Vis spectra displayed the absorption maxima of 424 nm for Fbf-AgNPs and in the case of Bbf-AgNPs, it was shown at 436 nm. The current research results demonstrated that both Fbf-AgNPs and Bbf-AgNPs displayed a strong α-glucosidase inhibition effect with more than 96% effect at 1 µg/mL concentration, but the Bbf-AgNPs displayed a slightly higher effect with IC₅₀ value slightly lower than the Fbf-AgNPs. Both Fbf-AgNPs and Bbf-AgNPs displayed good antioxidant effects concerning the in vitro antioxidant assays. In the case of the cytotoxicity potential assay also, among both the investigated Fbf-AgNPs and Bbf-AgNPs nanoparticles, the Bbf-AgNPs showed stronger effects with lower IC₅₀ value as compared to the Fbf-AgNPs. In conclusion, both the fern-mediated AgNPs displayed promising multi-therapeutic potential and could be beneficial in the cosmetics and pharmaceutical sectors. Though the synthesis process is rapid in Fbf-AgNPs, but it is concluded from the results of all the tested bio-potential assays, Bbf-AgNPs is slightly better than Fbf-AgNPs.

Key Health Benefits of Korean Ueong Dry Root Extract Combined Silver Nanoparticles

Introduction

Nowadays, in nanotechnology and material science, biosynthesis of the metal nanoparticle is a promising approach.

Methods

In the current research, the extract of the Korean Ueong dry root (BdkR), which belongs to the Asteraceae family, was used as a reducing and capping agent, for the green synthesis of the BdkR-Ag nanoparticles in a cost-effective and highly efficient manner. In this study for the reaction measures, UV-Vis spectroscopy was applied. SEM, EDX, FTIR, XRD, mean size distribution, and zeta potential were used for the characterization of the green synthesized BdkR-AgNPs. In the beginning, the primary phytochemical screening of BdkR extract was estimated and the cytotoxicity, antidiabetic, antioxidant, and antibacterial activities of the green synthesized BdkR-AgNPs were evaluated.

Results

According to the results, the BdkR extract is rich in various phytochemicals and the generated AgNPs were crystalline in nature. The surface plasmon resonance value of the BdkR-AgNPs was 444 nm confirming the synthesis of AgNPs. The BdkR-AgNPs displayed four clear diffraction peaks at 2 theta angles (38.22); (46.15); (64.88); (76.83), respectively, which are equivalent to (111), (200), (220) and (311). The obtained nanoparticles have a zeta potential of -17.0 mV. Furthermore, the generated BdkR-AgNPs exhibited considerable antidiabetic effect in terms of the inhibition of α-glucosidase with a maximum inhibition value of 95.41% at 5.0 µg/mL and more than 86% inhibition at 2.5 µg/mL and the estimated IC₅₀ value was found to be 0.653 µg/mL. Further, it also displayed a significant cytotoxicity activity against the HepG₂ cancer cell lines at 10 µg/mL and 100 µg/mL concentrations with 86% and 88% of inhibition, respectively. Besides this, the synthesized AgNPs also displayed promising antioxidant activities in terms of the DPPH (IC₅₀ value - 56.26 µg/mL), ABTS (IC₅₀ value - 171.43 µg/mL) and reducing power (IC_0.5 value - 227.42 µg/mL).

Discussion

The multipotential effects of the synthesized BdkR-AgNPs might be attributed to the presence of the bioactive compounds in the BdkR extract that acted as the capping and reducing agent in the synthesis process. The green synthesized BdkR-AgNPs exhibited promising bioactive potential for their future applications in the food and biomedical field.

Biogenic Silver Nanoparticles as a Stress Alleviator in Plants: A Mechanistic Overview

Currently, the growth and yield of crops are restrained due to an increase in the occurrence of ecological stresses globally. Biogenic generation of nanomaterials is an important step in the development of environmentally friendly procedures in the nanotechnology field. Silver-based nanomaterials are significant because of their physical, chemical, and biological features along with their plentiful applications. In addition to useful microbes, the green synthesized Ag nanomaterials are considered to be an ecologically friendly and environmentally biocompatible method for the enhancement of crop yield by easing stresses. In the recent decade, due to regular droughts, infrequent precipitation, salinity, and increased temperature, the climate alternation has changed certain ecological systems. As a result of these environmental changes, crop yield has decreased worldwide. The role of biogenic Ag nanomaterials in enhancing methylglyoxal detoxification, antioxidant defense mechanisms, and generating tolerance to stresses-induced ROS injury has been methodically explained in plants over the past ten years. However, certain studies regarding stress tolerance and metal-based nanomaterials have been directed, but the particulars of silver nanomaterials arbitrated stresses tolerance have not been well-reviewed. Henceforth, there is a need to have a good understanding of plant responses during stressful conditions and to practice the combined literature to enhance tolerance for crops by utilization of Ag nanoparticles. This review article illustrates the mechanistic approach that biogenic Ag nanomaterials in plants adopt to alleviate stresses. Moreover, we have appraised the most significant activities by exogenous use of Ag nanomaterials for improving plant tolerance to salt, low and high temperature, and drought stresses.

A Review on Plants and Microorganisms Mediated Synthesis of Silver Nanoparticles, Role of Plants Metabolites and Applications

Silver nanoparticles are one of the most extensively studied nanomaterials due to their high stability and low chemical reactivity in comparison to other metals. They are commonly synthesized using toxic chemical reducing agents which reduce metal ions into uncharged nanoparticles. However, in the last few decades, several efforts were made to develop green synthesis methods to avoid the use of hazardous materials. The natural biomolecules found in plants such as proteins/enzymes, amino acids, polysaccharides, alkaloids, alcoholic compounds, and vitamins are responsible for the formation of silver nanoparticles. The green synthesis of silver nanoparticles is an eco-friendly approach, which should be further explored for the potential of different plants to synthesize nanoparticles. In the present review we describe the green synthesis of nanoparticles using plants, bacteria, and fungi and the role of plant metabolites in the synthesis process. Moreover, the present review also describes some applications of silver nanoparticles in different aspects such as antimicrobial, biomedicine, mosquito control, environment and wastewater treatment, agricultural, food safety, and food packaging.

Testing of photocatalytic potential of silver nanoparticles produced through nonthermal plasma reduction reaction and stabilized with saccharides

In this study, silver nanoparticles (AgNPs) were produced through an atmospheric pressure plasma reduction reaction and tested for photodegradation of methyl blue (MB) under sunlight exposure. The argon plasma born reactive species were used to reduce silver ions to AgNPs in the solution. Glucose, fructose and sucrose were also added in the solution to stabilize the growth process. The glucose stabilized reaction produced the smallest nanoparticles of 12 nm, while sucrose stabilized reaction produced relatively larger nanoparticles (14 nm). The nanoparticles exhibited rough morphology and narrow diameter distribution regardless of stabilizer type. The narrow diameter distribution and small band gap helped activating majority of nanoparticles at a single wavelength of light spectrum. The band gap energy of AgNPs varied from 2.22 eV to 2.41 eV, depending on the saccharide type. The photoluminescence spectroscopy of AgNPs produced emission peaks at 413 nm, 415 nm, and 418 nm. The photocatalytic potential of AgNP samples was checked by degrading MB dye under sunlight. The degradation reaction reached a saturation level of 98% after 60 min of light exposure.

Metal Nanoparticles as Novel Antifungal Agents for Sustainable Agriculture: Current Advances and Future Directions

The use of metal nanoparticles is considered a good alternative to control phytopathogenic fungi in agriculture. To date, numerous metal nanoparticles (e.g., Ag, Cu, Se, Ni, Mg, and Fe) have been synthesized and used as potential antifungal agents. Therefore, this proposal presents a critical and detailed review of the use of these nanoparticles to control phytopathogenic fungi. Ag nanoparticles have been the most investigated nanoparticles due to their good antifungal activities, followed by Cu nanoparticles. It was also found that other metal nanoparticles have been investigated as antifungal agents, such as Se, Ni, Mg, Pd, and Fe, showing prominent results. Different synthesis methods have been used to produce these nanoparticles with different shapes and sizes, which have shown outstanding antifungal activities. This review shows the success of the use of metal nanoparticles to control phytopathogenic fungi in agriculture.

Bionanofactories for Green Synthesis of Silver Nanoparticles: Toward Antimicrobial Applications

Among the various types of nanoparticles and their strategy for synthesis, the green synthesis of silver nanoparticles has gained much attention in the biomedical, cellular imaging, cosmetics, drug delivery, food, and agrochemical industries due to their unique physicochemical and biological properties. The green synthesis strategies incorporate the use of plant extracts, living organisms, or biomolecules as bioreducing and biocapping agents, also known as bionanofactories for the synthesis of nanoparticles. The use of green chemistry is ecofriendly, biocompatible, nontoxic, and cost-effective. We shed light on the recent advances in green synthesis and physicochemical properties of green silver nanoparticles by considering the outcomes from recent studies applying SEM, TEM, AFM, UV/Vis spectrophotometry, FTIR, and XRD techniques. Furthermore, we cover the antibacterial, antifungal, and antiparasitic activities of silver nanoparticles.

Plant-based green synthesis of silver nanoparticles and its effective role in abiotic stress tolerance in crop plants

The development of effective and environmentally friendly methods for the green synthesis of nanoparticles (NPs) is a critical stage in the field of nanotechnology. Silver nanoparticles (AgNPs) are significant due to their unique physical, chemical, and biological properties, as well as their numerous applications. Physical, chemical, and green synthesis approaches can all be used to produce AgNPs; however, synthesis using biological precursors, particularly plant-based green synthesis, has shown outstanding results. In recent years, owing to a combination of frequent droughts, unusual rainfall, salt-affected areas, and high temperatures, climate change has changed several ecosystems. Crop yields have decreased globally as a result of these changes in the environment. Green synthesized AgNPs role in boosting antioxidant defense mechanisms, methylglyoxal (MG) detoxification, and developing tolerance for abiotic stress-induced oxidative damage has been thoroughly described in plant species over the last decade. Although various studies on abiotic stress tolerance and metallic nanoparticles (NPs) in plants have been conducted, but the details of AgNPs mediated abiotic stress tolerance have not been well summarized. Therefore, the plant responses to abiotic stress need to be well understood and to apply the gained knowledge to increase stress tolerance by using AgNPs for crop plants. In this review, we outlined the green synthesis of AgNPs extracted from plant extract. We also have updates on the most important accomplishments through exogenous application of AgNPs to improve plant tolerance to drought, salinity, low and high-temperature stresses.

Recent advances in anticancer and antimicrobial activity of silver nanoparticles synthesized using phytochemicals and organic polymers

Development of eco-friendly synthetic methods has resulted in the production of biocompatible Ag NPs for applications in medical sector. To overcome the prevailing antibiotic resistance in bacteria, Ag NPs are being extensively researched over the past few years due to their broad spectrum and robust antimicrobial properties. Silver nanoparticles are also being studied widely in advanced anticancer therapy as an alternative anticancer agent to combat cancer in an effective manner. Keeping this backdrop in consideration, this review aims to provide an extensive coverage of the recent progresses in the green synthesis of Ag NPs specifically using plant derived reducing agents such phytochemicals and numerous other biopolymers. Current development in antimicrobial activity of Ag NPs against various pathogens has been deliberated at length. Recent advances in potent anticancer activity of the biogenic Ag NPs against various cancerous cell lines has also been discussed in detail. Mechanistic details of the synthesis of Ag NPs, their anticancer and antimicrobial action has also been highlighted.

Bioinspired Nanomodification Strategies: Moving from Chemical-Based Agrosystems to Sustainable Agriculture

Agrochemicals have supported the development of the agricultural economy and national population over the past century. However, excessive applications of agrochemicals pose threats to the environment and human health. In the last decades, nanoparticles (NPs) have been a hot topic in many fields, especially in agriculture, because of their physicochemical properties. Nevertheless, the prevalent methods for fabricating NPs are uneconomical and involve toxic reagents, hindering their extensive applications in the agricultural sector. In contrast, inspired by biological exemplifications from microbes and plants, their extract and biomass can act as a reducing and capping agent to form NPs without any toxic reagents. NPs synthesized through these bioinspired routes are cost-effective, ecofriendly, and high performing. With the development of nanotechnology, biosynthetic NPs (bioNPs) have been proven to be a substitute strategy for agrochemicals and traditional NPs in heavy-metal remediation of soil, promotion of plant growth, and management of plant disease with less toxicity and higher performance. Therefore, bioinspired synthesis of NPs will be an inevitable trend for sustainable development in agricultural fields. This critical review will demonstrate the bioinspired synthesis of NPs and discuss the influence of bioNPs on agricultural soil, crop growth, and crop diseases compared to chemical NPs or agrochemicals.

Facile Synthesis of Carboxymethyl Cellulose Coated Core/Shell SiO2@Cu Nanoparticles and Their Antifungal Activity against Phytophthora capsici

Cu nanoparticles are a potential material for creating novel alternative antimicrobial products due to their unique antibacterial/antifungal properties, stability, dispersion, low cost and abundance as well as being economical and ecofriendly. In this work, carboxymethyl cellulose coated core/shell SiO2@Cu nanoparticles (NPs) were synthesized by a simple and effective chemical reduction process. The initial SiO2 NPs, which were prepared from rice husk ash, were coated by a copper ultrathin film using hydrazine and carboxymethyl cellulose (CMC) as reducing agent and stable agent, respectively. The core/shell SiO2@Cu nanoparticles with an average size of ~19 nm were surrounded by CMC. The results indicated that the SiO2@Cu@CMC suspension was a homogenous morphology with a spherical shape, regular dispersion and good stability. Furthermore, the multicomponent SiO2@Cu@CMC NPs showed good antifungal activity against Phytophthora capsici (P. capsici). The novel Cu NPs-based multicomponent suspension is a key compound in the development of new fungicides for the control of the Phytophthora disease.

Comparative Assessment of Antioxidant, Anti-Diabetic and Cytotoxic Effects of Three Peel/Shell Food Waste Extract-Mediated Silver Nanoparticles

Background

The natural food waste peels/shells discarded as waste materials are ample sources of natural bioactive compounds. The natural food waste mediated silver (Ag) nanoparticle (NPs) synthesis will be advantageous over chemical synthesis.

Materials and Methods

Using the various phytochemical-rich ripe P. americana peel (PAP), fresh Beta vulgaris peel (BVP), and rawArachis hypogaea shell (AHS) extracts, the bio-synthesis of PAP-AgNPs, BVP-AgNPs, and AHS-AgNPs, respectively, were carried out and its characterization was completed by standard procedures. The three biosynthesized AgNP's multiple biological effects were accomplished by evaluating their cytotoxicity, antidiabetic, and antioxidant effects.

Results

The biosynthesis of the three generated Ag nanoparticles was confirmed through UV-vis spectrum analysis while the X-ray diffraction outlines revealed the generated AgNPs nature. The morphological structure and elemental information of the three AgNPs were obtained through SEM (scanning electron microscopy) and EDX (energy-dispersive X-ray) study. Multiple biological assays exhibited that the three generated AgNPs have significant cytotoxic, antidiabetic, and moderate antioxidant activity. In a comparative analysis, the PAP-AgNPs displayed higher anticancer potential than BVP and AHS-AgNPs, whereas AHS-AgNPs exhibited a higher antidiabetic effect with the lowest IC₅₀ value (1.68 µg/mL) than PAP and BVP AgNPs. All three generated AgNPs displayed moderate antioxidant effects, among them BVP-AgNPs were more effective than PAP and AHS AgNPs. More than two effects of the three biosynthesized AgNPs specifies that they have ample perspective in therapeutic applications in pharmaceutical and other related industries in controlling cancer and diabetes.

Facile green synthesis and applications of silver nanoparticles: a state-of-the-art review

In the field of nanotechnology, the development of reliable and eco-friendly methods for the synthesis of NPs is crucial. The conventional methods for the synthesis of NPs are costly, toxic, and not ecofriendly. To overcome these issues, natural sources such as plant, bacteria, fungi, and biopolymers have been used to synthesize AgNPs. These natural sources act as reducing and capping agents. The shape, size, and applications of AgNPs are prominently affected by the reaction parameters under which they are synthesized. Accessible distributed data on the synthesis of AgNPs include the impact of different parameters (temperature and pH), characterization techniques (DLS, UV-vis, FTIR, XRD, SEM, TEM and EDX), properties and their applications. This review paper discusses all the natural sources such as plants, bacteria, fungi, and biopolymers that have been used for the synthesis of AgNPs in the last ten years. AgNPs synthesized by green methods have found potential applications in a wide spectrum of areas including drug delivery, DNA analysis and gene therapy, cancer treatment, antimicrobial agents, biosensors, catalysis, SERS and magnetic resonance imaging (MRI). The current limitations and future prospects for the synthesis of inorganic nanoparticles by green methods are also discussed herein.

Safe nanotechnologies for increasing the effectiveness of environmentally friendly natural agrochemicals

Natural compounds and living organisms continue to play a limited role in crop protection, and few of them have reached the market, despite their attractiveness and the efforts made in research. Very often these products have negative characteristics compared to synthetic compounds, e.g., higher costs of production, lower effectiveness, lack of persistence, and inability to reach and penetrate the target plant. Conversely, nanotechnologies are having an enormous impact on all human activities, including agriculture, even if the production of some nanomaterials is not environmentally friendly or could have adverse effects on agriculture and the environment. Thus, certain nanomaterials could facilitate the development of formulated natural pesticides, making them more effective and more environmentally friendly. Nanoformulations can improve efficacy, reduce effective doses, and increase shelf-life and persistence. Such controlled-release products can improve delivery to the target pest. This review considers certain available nanomaterials and nanotechnologies for use in agriculture, discussing their properties and the feasibility of their use in sustainable crop protection, in particular, in improving the effectiveness of natural bio-based agrochemicals. © 2019 Society of Chemical Industry.

Extracellular biosynthesis of bactericidal Ag/AgCl nanoparticles for crop protection using the fungus Macrophomina phaseolina

Synthesis of noble metal nanoparticles using natural products and living organisms has drawn a lot of interest owing to economic prospects and potential applicability in different fields. For this work we used the exudate of the soil fungus Macrophomina phaseolina for a low-cost method of green synthesis to obtain stable silver-silver chloride nanoparticles (Ag/AgCl-NPs). Reaction parameters including media and AgNO₃ concentration were further optimized for NPs production. Spectral analysis revealed a peak at 420 nm that corresponds to the surface plasmon resonance of silver NPs. Scanning electron microscopy (SEM) analysis unveiled NPs spherical morphology with a size range of 5-30 nm. The crystalline nature of the synthesized NPs was examined by X-ray diffraction (XRD) analysis. The green synthesized NPs showed activity against gram-positive and gram-negative bacteria. No effect in fungi or yeast cells was detected, though a high inhibitory effect was observed on bacteria growth kinetics. Interaction of bacteria with Ag/AgCl-NPs led to cell membrane damage as observed by SEM, followed by an increase in oxidative stress, being this the possible mechanism behind the strong bactericidal activity depicted. In order to test its possible applicability as a seed protection agent the effect of Ag/AgCl-NPs dosage on soybean (Glycine max L.) seed's germination was also examined. Interestingly, not only the germination process was not affected by the NPs dosage or time of seeds incubation, but also no oxidative damage was detected in seeds after exposure to the biogenic nanoparticles.

Plant-based metallic nanoparticles as potential theranostics agents: bioinspired tool for imaging and treatment

Theranostic approach provides us a platform where diagnosis and treatment can be carried out simultaneously. Biosynthesis of theranostic-capable nanoparticles (NPs) can be carried out by phytoconstituents present inside the plants that can act as capping as well as stabilising agents by offering several advantages over chemical and physical methods. This article highlights the theranostic role of NPs with emphasis on potential of plants to produce these NPs through ecofriendly approach that is called 'Green synthesis'. Biosynthesis, advantages, and disadvantages of plant-based theronostics have been discussed for better understanding. Moreover, this article has highlighted the approaches required to optimise the plant-mediated synthesis of NPs and to avoid the toxicity of these agents. Anticipating all of the challenges, the authors expect biogenic NPs can appear as potential diagnostic and therapeutic agents in near future.

Use of agricultural waste (coconut shell) for the synthesis of silver nanoparticles and evaluation of their antibacterial activity against selected human pathogens

Green synthesis of silver nanoparticles (AgNPs) is environmentally satisfactory because of their low cost and safe to nature. In the present study, extract of an agricultural waste, coconut (Cocos nucifera) shell is used to synthesize AgNPs and their antibacterial effect was investigated against selected human pathogens Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium. The AgNPs synthesized using coconut shell extract (CSE-AgNPs) were characterized using UV-Visible spectroscopy (absorption peak at 432 nm), Transmission Electron Microscopy (spherical shaped particles size of 14.2-22.96 nm), Fourier-Transform Infrared Spectroscopy indicating the CSE capping around the AgNPs (Peaks 1384, 1609 and 3418 corresponds to organic molecules) and X-Ray Diffraction (Peak at 32.078 and 2-Theta). CSE-AgNPs exhibited zone of inhibition against S. aureus (15 mm), E. coli (13 mm), S. typhimurium (13 mm) and L. monocytogenes (10 mm) and minimum inhibitory concentration (MIC) of 26, 53, 106 and 212 μg/ml, respectively. Growth curve assay showed the effectiveness of CSE-AgNPs to inhibit the selected pathogens when compared to amphicillin control and extract. Scanning electron microscopy results indicated that the cell wall degradation might be the possible mechanism of antibacterial action of CSE-AgNPs. Different concentrations of AgNPs (0.078-2.5 mg/ml) showed no toxicity against human PBMC cell line. Hence, such highly effective CSE-AgNPs could be explored as antibacterial agent.

A review on green synthesis of silver nanoparticles and their applications

Development of reliable and eco-accommodating methods for the synthesis of nanoparticles is a vital step in the field of nanotechnology. Silver nanoparticles are important because of their exceptional chemical, physical, and biological properties, and hence applications. In the last decade, numerous efforts were made to develop green methods of synthesis to avoid the hazardous byproducts. This review describes the methods of green synthesis for Ag-NPs and their numerous applications. It also describes the comparison of efficient synthesis methods via green routes over physical and chemical methods, which provide strong evidence for the selection of suitable method for the synthesis of Ag-NPs.