Green synthesis of silver nanoparticles with the Arial part of Dorema ammoniacum D. extract by antimicrobial analysis

Bioinspired and Green Synthesis of Silver Nanoparticles for Medical Applications: A Green Perspective

Silver nanoparticles (AgNPs) possess unmatched chemical, biological, and physical properties that make them unique compounds as antimicrobial, antifungal, antiviral, and anticancer agents. With the increasing drug resistance, AgNPs serve as promising entities for targeted drug therapy against several bacterial, fungal, and viral components. In addition, AgNPs also serve as successful anticancer agents against several cancers, including breast, prostate, and lung cancers. Several works in recent years have been done towards the development of AgNPs by using plant extracts like flowers, leaves, bark, root, stem, and whole plant parts. The green method of AgNP synthesis thus has several advantages over chemical and physical methods, especially the low cost of synthesis, no toxic byproducts, eco-friendly production pathways, can be easily regenerated, and the bio-reducing potential of plant derived nanoparticles. Furthermore, AgNPs are biocompatible and do not harm normally functioning human or host cells. This review provides an exhaustive overview and potential of green synthesized AgNPs that can be used as antimicrobial, antifungal, antiviral, and anticancer agents. After a brief introduction, we discussed the recent studies on the development of AgNPs from different plant extracts, including leaf parts, seeds, flowers, stems, bark, root, and whole plants. In the following section, we highlighted the different therapeutic actions of AgNPs against various bacteria, fungi, viruses, and cancers, including breast, prostate, and lung cancers. We then highlighted the general mechanism of action of AgNPs. The advantages of the green synthesis method over chemical and physical methods were then discussed in the article. Finally, we concluded the review by providing future perspectives on this promising field in nanotechnology.

Enhanced antibacterial properties and magnetic removal of Fe3O4/fenugreek seed gum/silver nanocomposites for water treatment

This study reports the synthesis, characterization, and antibacterial activity of a novel Fe3O4 nanocomposite coated with fenugreek seed gums and silver nanoparticles (AgNPs). To enhance the antibacterial properties of AgNPs and overcome the limitations of conventional methods for the production of three-component nanocomposites, a layer of natural polymer was used. Fenugreek seed gums (FSG) were used to coat Fe3O4 NPs to prevent their decomposition and to facilitate the release of silver nanoparticles in aqueous media. The Fe3O4/FSG/Ag nanocomposites were characterized and then the antibacterial activity of the nanocomposites was evaluated against two gram-negative and two gram-positive bacteria and compared with Fe3O4, Fe3O4/FSG, FSG, and AgNO3. The results showed that the Fe3O4/FSG/Ag nanocomposites had higher antibacterial activity than the other samples and could be easily removed from treated water by a powerful magnet without causing pollution in the environment. Overall, these findings suggest that the Fe3O4/FSG/Ag nanocomposites have potential applications in water treatment for their improved antibacterial properties and ease of removal.

Biogenic silver based nanostructures: Synthesis, mechanistic approach and biological applications

The alarming impact of antibiotic resistance sparked the quest for complementary treatments to overcome the confrontation over resistant pathogens. Metallic nanoparticles, especially silver nanoparticles (Ag NPs) have gained a much attention because of their remarkable biological characteristics. Moreover, their medicinal properties can be enhanced by preparing the composites with other materials. This article delves a comprehensive review of biosynthesis route for Ag NPs and their nanocomposites (NCs) with in-depth mechanism, methods and favorable experimental parameters. Comprehensive biological features Ag NPs such as antibacterial, antiviral, antifungal have been examined, with a focus on their potential uses in biomedicine and diagnostics has also been discussed. Additionally, we have also explored the hitches and potential outcomes of biosynthesis of Ag NPs in biomedical filed.

Phytotoxicity and Antimicrobial Activity of Green Synthesized Silver Nanoparticles Using Nigella sativa Seeds on Wheat Seedlings

Recently, the green synthesis of nanomaterials has grown in popularity and has become one of the most used approaches. Plant extracts are safe for the environment and could be cost-effective for nanoparticle preparation. Silver nanoparticles (AgNPs) have been synthesized using aqueous extracts of Nigella sativa (N. sativa) seeds. The formation of AgNPs was confirmed by using an X-ray diffractometer, a UV-visible spectrometer, and a transmission electron microscope. The phytotoxicity and genotoxicity of different AgNP concentrations (12.5, 25, 50, 75, and 100 μg·L−1) were evaluated by wheat (Triticum aestivum L.) seed germination. The results showed that AgNPs did not significantly affect germination, while root and coleoptile lengths decreased considerably. On the contrary, the biomass of seedlings markedly increased in response to AgNP treatments. Moreover, genotoxicity was detected, especially at high concentrations of AgNPs. DNA, RNA, and total soluble proteins of wheat seedlings significantly decreased. In addition, antimicrobial activities of biosynthesized AgNPs were detected.

Phytochemical Analysis, In Vitro Anticholinesterase, Antioxidant Activity and In Vivo Nootropic Effect of Ferula ammoniacum (Dorema ammoniacum) D. Don. in Scopolamine-Induced Memory Impairment in Mice

Background: Ferula ammoniacum (D. Don) is one of the endemic medicinal plants that is traditionally used to treat a number of diseases. Although the plant has been used to enhance memory, the investigational evidence supporting the nootropic effect was unsubstantial. Hence, the rationale for this study was to assess the potential beneficial effect of F. ammoniacum seed extracts on learning and memory in mice. Methods: The powdered plant samples (aerial parts) were subjected to extraction ad fractionation. Among the extracts, crude and ethyl acetate extracts were screened for major phytochemicals through HPLC analysis. All the extracts were evaluated for the in vitro anticholinesterase (AChE and BChE) and antioxidant potentials. Among the extracts the active fraction was further assessed for improving learning and memory in mice using behavioural tests like Y-maze and novel object recognition test (NORT) using standard protocols. After behavioural tests, all the animals were sacrificed and brains tissues were assessed for the ex vivo anticholinesterase and antioxidant potentials. Results: Phytochemicals like chlorogenic acid, quercetin, mandelic acid, phloroglucinol, hydroxy benzoic acid, malic acid, epigallocatechin gallate, ellagic acid, rutin, and pyrogallol were identified in crude methanolic extract (Fa.Met) and ethyl acetate fraction (Fa.EtAc) through HPLC. Fa.EtAc and Fa.Chf extracts more potently inhibited AChE and BChE with IC50 values of 40 and 43 µg/mL, and 41 and 42 µg/mL, respectively. Similarly highest free radical scavenging potential was exhibited by Fa.EtAc fraction against DPPH (IC50 = 100 µg/mL) and ABTS (IC50 = 120 µg/mL). The extract doses, 100 and 200 mg/kg body weight significantly (p < 0.01) improved the short-term memory by increasing the percent spontaneous alternation in the Y-maze test along with increasing discrimination index in the NORT that clearly indicated the enhancement in the recognition memory of mice. Conclusion: The extracts more potently scavenged the tested free radicals, exhibited anticholinesterase activities, improved the learning abilities and reduced the memory impairment induced by scopolamine in mice model thus suggesting that these extracts could be effectively used for the management of oxidative stress, neurodegenerative diseases and memory loss.

Green synthesis of silver nanoparticles using plant extracts and their antimicrobial activities: a review of recent literature

Synthesis of metal nanoparticles using plant extracts is one of the most simple, convenient, economical, and environmentally friendly methods that mitigate the involvement of toxic chemicals. Hence, in recent years, several eco-friendly processes for the rapid synthesis of silver nanoparticles have been reported using aqueous extracts of plant parts such as the leaf, bark, roots, etc. This review summarizes and elaborates the new findings in this research domain of the green synthesis of silver nanoparticles (AgNPs) using different plant extracts and their potential applications as antimicrobial agents covering the literature since 2015. While highlighting the recently used different plants for the synthesis of highly efficient antimicrobial green AgNPs, we aim to provide a systematic in-depth discussion on the possible influence of the phytochemicals and their concentrations in the plants extracts, extraction solvent, and extraction temperature, as well as reaction temperature, pH, reaction time, and concentration of precursor on the size, shape and stability of the produced AgNPs. Exhaustive details of the plausible mechanism of the interaction of AgNPs with the cell wall of microbes, leading to cell death, and high antimicrobial activities have also been elaborated. The shape and size-dependent antimicrobial activities of the biogenic AgNPs and the enhanced antimicrobial activities by synergetic interaction of AgNPs with known commercial antibiotic drugs have also been comprehensively detailed.

Antibacterial magnetic nanoparticles for therapeutics: a review

Along with the extensive range of exotic nanoparticle (NPs) applications, investigation of magnetic NPs (MNPs) in vitro has ushered modern antibacterial studies into an increasingly attractive research area. A great number of microorganisms exist in the size scales from nanometre to micrometre regions. The enormous potential of engineered MNPs in therapeutic procedures against various drug-resistant bacteria has declined the menace of fatal bacterial infections. Many biocompatible MNPs have been introduced that possess remarkable impacts on various bacterial strains. Conventional synthesis methods such as co-precipitation or hydrothermal techniques have been widely adopted in the production of MNPs. The MNPs for antibacterial applications are mainly required to be superparamagnetic, recyclable and biocompatible. To implement novel strategies in developing new generation antimicrobial magnetic nanomaterials, it is essential to obtain a comprehensive preview of recent achievements in synthesis, proposed antibacterial mechanisms and characterisation techniques of these nanomaterials. This review highlights notable aspects of antibacterial activity in engineered MNPs and nanocomposites including their particle properties (size, shape and saturation magnetisation), antibacterial mechanisms, synthesis methods, testing methods, surface modifications and minimum inhibitory concentrations.

Green synthesis of silver nanoparticles using Glaucium corniculatum (L.) Curtis extract and evaluation of its antibacterial activity

The metal nanoparticles, due to interesting features such as electrical, optical, chemical and magnetic properties, have been investigated repeatedly. Also, the mentioned nanoparticles have specific uses in terms of their antibacterial activity. The biosynthesis method is more appropriate than the chemical method for producing the nanoparticles because it does not need any special facilities; it is also economically affordable. In the current study, the silver nanoparticles (AgNPs) were obtained by using a very simple and low-cost method via Glaucium corniculatum (L.) Curtis plant extract. The characteristics of the AgNPs were investigated using techniques including: X-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy. The SEM and TEM images showed that the nanoparticles had a spherical shape, and the mean diameter of them was 53.7 and 45 nm, respectively. The results of the disc diffusion test used for measuring the anti-bacterial activity of the synthesised nanoparticles indicated that the formed nanoparticles possessed a suitable anti-bacterial activity.

Core@shell Nanoparticles: Greener Synthesis Using Natural Plant Products

Among an array of hybrid nanoparticles, core-shell nanoparticles comprise of two or more materials, such as metals and biomolecules, wherein one of them forms the core at the center, while the other material/materials that were located around the central core develops a shell. Core-shell nanostructures are useful entities with high thermal and chemical stability, lower toxicity, greater solubility, and higher permeability to specific target cells. Plant or natural products-mediated synthesis of nanostructures refers to the use of plants or its extracts for the synthesis of nanostructures, an emerging field of sustainable nanotechnology. Various physiochemical and greener methods have been advanced for the synthesis of nanostructures, in contrast to conventional approaches that require the use of synthetic compounds for the assembly of nanostructures. Although several biological resources have been exploited for the synthesis of core-shell nanoparticles, but plant-based materials appear to be the ideal candidates for large-scale green synthesis of core-shell nanoparticles. This review summarizes the known strategies for the greener production of core-shell nanoparticles using plants extract or their derivatives and highlights their salient attributes, such as low costs, the lack of dependence on the use of any toxic materials, and the environmental friendliness for the sustainable assembly of stabile nanostructures.