Plant-mediated Synthesis Of Silver Nanoparticles Research Articles

Plant-mediated synthesis of silver nanoparticles: unlocking their pharmacological potential-a comprehensive review.

In recent times, nanoparticles have experienced a significant upsurge in popularity, primarily owing to their minute size and their remarkable ability to modify physical, chemical, and biological properties. This burgeoning interest can be attributed to the expanding array of biomedical applications where nanoparticles find utility. These nanoparticles, typically ranging in size from 10 to 100nm, exhibit diverse shapes, such as spherical, discoidal, and cylindrical configurations. These variations are not solely influenced by the manufacturing processes but are also intricately linked to interactions with surrounding stabilizing agents and initiators. Nanoparticles can be synthesized through physical or chemical methods, yet the biological approach emerges as the most sustainable and eco-friendly alternative among the three. Among the various nanoparticle types, silver nanoparticles have emerged as the most encountered and widely utilized due to their exceptional properties. What makes the synthesis of silver nanoparticles even more appealing is the application of plant-derived sources as reducing agents. This approach not only proves to be cost-effective but also significantly reduces the synthesis time. Notably, silver nanoparticles produced through plant-mediated processes have garnered considerable attention in recent years due to their notable medicinal capabilities. This comprehensive review primarily delves into the diverse medicinal attributes of silver nanoparticles synthesized using plant-mediated techniques. Encompassing antimicrobial properties, cytotoxicity, wound healing, larvicidal effects, anti-angiogenesis activity, antioxidant potential, and antiplasmodial activity, the paper extensively covers these multifaceted roles. Additionally, an endeavor is made to provide an elucidated summary of the operational mechanisms underlying the pharmacological actions of silver nanoparticles.

Plant-mediated Synthesis of Silver Nanoparticles using Mangosteen Pericarp Extract and their Antimicrobial Potential

Introduction: Silver nanoparticles (AgNPs) were synthesized using mangosteen pericarp ethanolic extract (MPEE) as a source of bioreductants and their antimicrobial activity against common foodborne pathogens was evaluated. Methods: Characterization of MPEE was conducted using phytochemical screening, total phenolic content analysis, and DPPH (antioxidant) assay. Synthesis AgNPs and optimization studies were monitored using UV-Vis spectrophotometry. Transmission electron microscopy was used to characterize the AgNPs, and resazurin microtiter assay was used for antimicrobial testing. Results: Alkaloids, flavonoids, saponins, quinones, anthraquinones, and tannins were confirmed present in the extract. TPC and IC50 of MPEE were 0.192 mg GAE/mg extract and 0.277 mg/mL, respectively. A surface plasmon resonance (SPR) peak within 450-403 nm confirmed the formation of AgNPs. At pH 7, the optimum reaction conditions were 45°C and 3 h. Meanwhile, at pH 9, the optimum reaction conditions were 27°C and 0.5 h. The sizes of nanoparticles synthesized at pH 7 and pH 9 were 13-35 nm and 7- 38 nm, respectively. The minimum inhibitory concentration (MIC90) of AgNPs produced at pH 7 were 1.45, 2.81, and 2.93 ug/mL for S. aureus, E.coli, and B. cereus, respectively. For AgNPs synthesized at pH 9, the MIC90 were 2.93, 3.02, and 5.24 ug/mL, for the same microorganisms, respectively. Conclusion: MPEE was able to successfully synthesize AgNPs. Compared to chloramphenicol, AgNPs exhibited better antimicrobial activity, which can address the growing concern of drug resistance in certain pathogenic microorganisms. Furthermore, the use of MPEE provides a green and sustainable alternative to synthesizing AgNPs.

Evaluation of the Antioxidant, Antidiabetic, and Anticholinesterase Potential of Biogenic Silver Nanoparticles from Khaya grandifoliola.

In recent years, plant-mediated synthesis of silver nanoparticles has evolved as a promising alternative to traditional synthesis methods. In addition to producing silver nanoparticles with diverse biomedical potential, the biosynthesis approach is known to be inexpensive, rapid, and environmentally friendly. This study was aimed at synthesizing silver nanoparticles using ethanolic stem and root bark extracts of Khaya grandifoliola and highlighting the biomedical potential of the nanoparticles by evaluating their antioxidant, antidiabetic and anticholinesterase effects in vitro. Silver nanoparticles were prepared using ethanolic stem and root bark extracts of K. grandifoliola as precursors. The biogenic silver nanoparticles were characterized using UV-visible spectroscopy, fourier transform infrared spectroscopy, scanning electron microscopy and energydispersive X-ray analysis. Furthermore, 2,2-Diphenyl-1-picrylhydrazyl radical scavenging, ferric ion reducing antioxidant power, and nitric oxide scavenging assays were used to determine the antioxidant property of the nanoparticles. The antidiabetic potential of the nanoparticles was determined by evaluating their inhibitory effect on the activity of α-amylase and α-glucosidase. The anticholinesterase potential of the nanoparticles was determined by assessing their inhibitory effect on the activity of acetylcholinesterase and butyrylcholinesterase. UV-visible spectroscopy showed surface plasmon resonance bands between 425 and 450 nm. Scanning electron microscopy revealed almost round nanoparticles with a maximum size of 91 nm. Fourier transform infrared spectroscopy affirmed the role of the phytoconstituents present in K. grandifoliola as reducing and stabilizing agents. The biogenic silver nanoparticles showed remarkable antioxidant, antidiabetic, and anticholinesterase effects. Biogenic silver nanoparticles could be useful in biomedical and pharmacological applications.

Assessment of therapeutic potential of silver nanoparticles synthesized by Ferula Pseudalliacea rech. F. plant

Plant-mediated synthesis of silver nanoparticles (Ag NPs) has increased its use in various biomedical applications due to its cost-effectiveness, renewable and environmentally friendly properties. Therefore, the focus of the study was to synthesize Ag NPs and to evaluate their antibacterial, and antioxidant activities by using the aqueous root extract of Ferula pseudodalliacea plant as a reducing agent. In addition, the synthesis of nanoparticles was confirmed by performing Ag NPs/Fp characterization processes. According to the findings of our research, color change due to surface plasmon resonance was confirmed by UV–vis spectrometry. The crystal properties of Ag NPs/Fp were determined according to the XRD model. Phytochemicals responsible for coating and reduction of Ag NPs/Fp were observed by FT-IR analysis. It has been shown that the therapeutic effect of Ag NPs/Fp exhibits better antimicrobial and antioxidant activity than aqueous extract. In addition, it was determined that Ag NPs/Fp structures showed the best antifungal effect against Candida albicans ATTC 90028 pathogen and gave a better zone than Rifampicin antibiotic. Therefore, studies at the molecular level and more comprehensively are required to determine the bioactive components and pharmacological effects of Ferula pseudodalliacea plant to confirm our antibacterial, antioxidant, and antifungal activity results.

Biosynthesis of silver nanoparticles using three different fruit extracts: Characterization, formation mechanism and estrogen removal

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

Biogenic silver nanoparticles induce apoptosis in Ehrlich ascites carcinoma

Introduction: Plant-mediated synthesis of silver nanoparticles (AgNPs) is accounted as an ecofriendly process. The present study was conducted to estimate the potency of biogenic AgNPs against Ehrlich ascites carcinoma (EAC) cells in vitro and EAC-bearing mice in vivo.
 Methods: AgNPs were prepared using mango leaves extract and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM). Ehrlich ascites carcinoma (EAC) mouse model was established by intraperitoneal injection of 1 x 106 EAC cells. Biogenic AgNPs- alone or combined with Doxorubicin (DOX)- was administered intraperitoneally day by day for two weeks.
 Results: Biologically synthesized AgNPs showed a cytotoxic effect against cultured EAC cells but with less toxicity toward normal cells compared to DOX, which had strong cytotoxicity against both cells. Biogenic AgNPs alone or combined with DOX triggered the cytotoxicity against the EAC-bearing mouse model via decreasing body weight, tumor volume, and the number of viable tumor cells. The combined treatment (AgNPs-DOX) ameliorated the drastic effect induced by injection of EAC cells through improving liver and kidney functions compared to those treated with DOX alone. In addition, the combined treatment showed an elevation in the expression of Bax and caspase-3, and a reduction in the expression of Bcl-2 protein in the EAC cells. Furthermore, this combined treatment effectively arrested the cell cycle at the G0/G1 phase. Moreover, the combined treatment with AgNPs-DOX caused a significant reduction in the activity of ornithine decarboxylase (ODC).
 Conclusion: These findings suggest that biogenic AgNPs could be useful in developing a potent combination therapy against different types of cancers.

An eco-friendly plant-mediated synthesis of silver nanoparticles: Characterization, pharmaceutical and biomedical applications

The current study focused on green chemistry approach to synthesize eco-friendly AgNPs using an aqueous extract of peganum harmala leaves. The formed AgNPs were characterized using different spectroscopic and microscopic analyses: ultraviolet–visible spectrophotometry (UV–Vis), Fluorolog 3 spectrometry, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR), techniques using a Zetasizer. The resulted nanoparticles were screened for their biomedical and pharmaceutical properties. They investigated for antimicrobial activity against various strains of bacteria and fungi. The synthesized AgNPs showed a higher antibacterial potential against Gram negative pathogen E. coli with inhibition zone of 65 mm rather than both Gram positive pathogens S. aurous and B. cereus of inhibition zone 50 mm. Meanwhile, no inhibition zone was observed for E. faecalis. Furthermore, the formed AgNPs were applied to enhance the sensitivity and selectivity of the spectrophotometric determination of the antibiotic Rifaximin in bulk powder or tablet form with a λmax of 340 nm. The proposed spectrophotometric technique for determining Rifaximin in the presence of silver nanoparticles showed a linear relationship in the concentration ranges of 5–80 μg/mL and followed the linear regression equation A = 0.039C-0.166 (r = 0.9997), with low limits of detection and quantification of 1.75 and 5.0 μg mL −1, respectively. According to the ICH guidelines, the proposed technique was validated.

Helminthicidal and Larvicidal Potentials of Biogenic Silver Nanoparticles Synthesized from Medicinal Plant Momordica charantia.

The drug formulations used to control mosquito vectors and helminth infections have resulted in the development of resistance, and negative impact on non-target organisms and environment. Plant-mediated synthesis of silver nanoparticles (P-AgNPs) using aqueous fruit peel extract of M. charantia, applications of P-AgNPs for helminthicidal activity against Indian earthworms (P. posthuma) and larvicidal activity against larvae of mosquito A. albopictus and A. aegypti. Aqueous fruit peel extract of Momordica charantia was used to reduce silver ions to silver nanoparticles (P-AgNPs). UV-Visible (UV-Vis) Spectroscopy, X-ray diffraction, Fourier Transform Infrared Spectroscopy and Transmission Electron Microscopy characterize synthesized P-AgNPs. The motility and survival rate of the worms were recorded for the helminthicidal activity. Percent mortality of larvae of A. albopictus and A. aegypti was recorded for larvicidal activity. The UV-Vis absorption spectrum of P-AgNPs showed a strong surface plasmon absorption band in the visible region with a maximum absorption at 445 nm indicating the synthesis of silver nanoparticles by the addition of aqueous fruit peel extract. The XRD spectrum of P-AgNPs showed Bragg's reflection peaks 2θ value characteristics for the Face-Centered Cubic (FCC) structure of silver. The sharp absorption peak in FTIR at 1659 cm-1 assigned to C=O stretching vibration in carbonyl compounds represents terpenoids, flavonoids and polyphenols in the corona of PAgNPs; a 2 mg/mL of P-AgNPs. The concentration aqueous extract and P-AgNPs showed complete death of worms (the morphological alteration/coiling of body). A 20 ppm concentration of PAgNPs showed 85% mortality in larvae of Ae. albopictus and Ae. aegypti. P-AgNPs were nontoxic at low concentrations. The aqueous extracts played a dual role as reducing and capping agent during the biosynthesis of AgNPs as per FTIR and XRD results. The surface reactivity facilitated by biomolecule corona attached to silver nanoparticles can further help to functionalize AgNPs in various pharmaceuticals, biomedicals, and environmental applications.

Antimicrobial, Cytotoxicity and Photocatalytic Degradation of Norfloxacin Using Kleinia grandiflora Mediated Silver Nanoparticles

Synthesis of nanomaterials through green and eco-friendly approaches which are free from toxic chemicals is an emerging interest in the field of nanoscience and nanotechnology. Plant-mediated synthesis of silver nanoparticles (AgNPs) gained importance because of its non-toxic, eco-friendly and potential for biomedical applications. The present study explored the synthesis of AgNPs using Kleinia grandiflora leaf extract (KGLE) as a reducing and stabilizing agent. The synthesized AgNPs were characterized via UV–Vis spectroscopy (UV–Vis), Fourier transform-infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The biosynthesized AgNPs were found to be spherical in shape and particle size in the range of 20–50 nm. Besides, the synthesized AgNPs showed significant antimicrobial efficacy against Pseudomonas aeruginosa and Aspergillus niger as well as considerable cytotoxicity towards Dalton’s lymphoma ascites cells with 100% inhibition at the concentration of 200 µg/mL of Ag-NPs. Furthermore, the photocatalytic degradation of norfloxacin under visible light irradiation explored the better reducing ability after 80 min of exposure time It is envisioned that KGLE mediated synthesized AgNPs may have a better antimicrobial, cytotoxic and photocatalytic agent in future.

Short Review: The Effect of Reaction Conditions on Plant-Mediated Synthesis of Silver Nanoparticles

Recently, interest in plant-mediated synthesis of the silver nanoparticles (AgNPs) is growing among researchers and till now the potential of different plants is still further explored to synthesize nanoparticles. Conventionally, AgNPs are synthesized using chemical and physical methods. However, these methods involve use of toxic and hazardous chemicals which are harmful to health and environment. Therefore, plant-mediated synthesis has been used as environmental friendly alternative to overcome the limitation of conventional methods. The bioactive compounds in plant acts as natural reducing and stabilizing agents which help to increase the rate of synthesis and stabilization of synthesized nanoparticles. Besides, the nanoparticles synthesized using plants are reported to be more stable and the rate of synthesis is much faster compared to other methods. This review focuses on the biosynthesis of AgNPs using plant as natural source plant and the effect of reaction conditions are summarised and discussed.

Plant-Mediated Synthesis of Silver Nanoparticles – A Critical Review

Nanomedicine is a revolutionary science nanoparticles of size 1 - 100nm designed for the utilization in disease diagnostics and therapeutics, targeted drug delivery of drugs which have difficulty in solubility and bioavailability and also to be applied in numerous fields. The present critical review aims at enumerating the advantages, synthesis and characterization methods, as well as diversified applications of green silver nanoparticles. Silver nanoparticles is an attractive proposition due to their distinctive physical, chemical and biological properties including a high electrical as well as thermal conductivity, surface-enhanced Raman scattering, chemical stability, catalytic activity and non linear optical behavior which enables them of potential value in inks, microelectronics, and medical imaging. Plant mediated synthesis of silver nanoparticles (AgNPs) is now-a-day’s gaining enormous interest as it is cost effective, ecofriendly and has less side effects since there is no addition of external stabilizing or capping agents as the plant itself acts as stabilizing or capping agent. The secondary metabolites and other plant products like proteins, metabolites like alkaloids, terpinoids, saponins, glycosides etc are known to act as external stabilizing or capping agents. The plant mediated silver nanoparticles are known to show uniform particles characteristics and morphology. The bottom to top end approach of synthesis is effective to achieve desired particles size, shape and morphology. The synthesized green silver nanoparticles are characterized by UVVis spectroscopy, SEM/TEM analysis, EDAX/EDS, FTIR and other methods zeta potential measurement, thermo gravimetric analysis, Raman scattering. The plant mediated synthesized silver nanoparticles (green silver nanoparticles) are effective in delivering pharmacological activities like antimicrobial, anticancer, larvicidal etc. Also green Silver nanoparticles have diverse applications acting as biosensors, as targeted drug delivery candidates, in diagnostics and therapeutics, in medical and consumer products, as anti pollutant and in agriculture. The future perspective holds promising results in green synthesis of silver nanoparticles involving plants. This review projects a collective sequence of information for synthesizing and evaluation of green silver nanoparticles and scope of its pharmacological actions.

The influence of different reaction parameters on plant-mediated synthesis of silver nanoparticles from Citrus grandis

The influence of different reaction parameters on plant-mediated synthesis of silver nanoparticles from Citrus grandis

Plant-mediated synthesis of silver nanoparticles using fruit extract of Cleome viscosa L.: Assessment of their antibacterial and anticancer activity

Green synthesis of silver nanoparticles was successfully done using Cleome viscosa plant extract, simple, rapid, eco-friendly and a cheaper method. In this study, we used C. viscosa extract for synthesizing silver nanoparticles which reduces silver nitrate into silver ions. The obtained AgNPs were characterized by UV, FTIR, XRD, FESEM-EDAX and TEM analysis. They were also analyzed for their biological activities. The presence of biosynthesized AgNPs (410–430 nm) was confirmed by UV–visible spectroscopy and also crystal nature of AgNPs confirmed through XRD analysis; FT-IR spectrum was used to confirm the presence of different functional groups in the biomolecules which act as a capping agent for the nanoparticles. The morphology of AgNPs was analyzed using SEM and the presence of silver was confirmed through elemental analysis. The size of the nanoparticles was in the range of 20–50 nm determined by TEM. The green synthesized AgNPs exhibited a good antibacterial activity against both Gram negative and Gram positive bacteria. Furthermore, the green synthesized AgNPs showed reliable anticancer activity on the lung (A549) and ovarian (PA1) cancer cell lines.

ANTIBACTERIAL ACTIVITY OF SYNTHESIZED SILVER NANOPARTICLES BY SIMAROUBAGLAUCA AGAINST PATHOGENIC BACTERIA

Objective: The present study outline the plant-mediated synthesis of silver nanoparticles (AgNPs) using leaf extract Simaroubaglauca, which act as both reducing and stabilizing agent.Methods: Formation of silver nanoparticles was confirmed by primarily by Ultraviolet/visible spectroscopy. X-ray diffraction studies revealed the crystallinity of the nanoparticles. The scanning electron microscopy was carried out to determine the mean particle size, as well as the morphology of the NPs and the composition of elements, was studied with Energy Dispersive X-ray analysis (EDS).Results: The silver nanoparticles were spherical in shape with a mean size of 23 nm. The EDS showed strong optical absorption peak at 3keV and it was confirmed the formation of AgNPs. The synthesised AgNPs further utilized for the evaluation of antibacterial activity and shown significant antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Enterobacter and Klebsiella pneumonia at 50 µg/ml and 100µg/ml concentrations.Conclusion: The synthesised silver nanoparticles have been characterised by UV-vis, SEM-EDAX and XRD to determine the sizes and shapes of the silver nanoparticles.

Plant-Mediated Synthesis of Silver Nanoparticles and Their Stabilization by Wet Stirred Media Milling

Within this study, a stable nanosuspension of silver nanoparticles (Ag NPs) was prepared using a two-step synthesis and stabilization approach. The Ag NPs were synthesized from a silver nitrate solution using the Origanum vulgare L. plant extract as the reducing agent. The formation of nanoparticles was finished upon 15 min, and subsequently, stabilization by polyvinylpyrrolidone (PVP) using wet stirred media milling was applied. UV-Vis spectra have shown a maximum at 445 nm, corresponding to the formation of spherical Ag NPs. Infrared spectroscopy was used to examine the interaction between Ag NPs and the capping agents. TEM study has shown the formation of Ag NPs with two different average sizes (38 ± 10 nm and 7 ± 3 nm) after the plant-mediated synthesis, both randomly distributed within the organic matrix. During milling in PVP, the clusters of Ag NPs were destroyed, the Ag NPs were fractionized and embedded in PVP. The nanosuspensions of PVP-capped Ag NPs were stable for more than 26 weeks, whereas for the non-stabilized nanosuspensions, only short-term stability for about 1 week was documented.

Evaluation of Silver Nanoparticle Toxicity of Coleus aromaticus Leaf Extracts and its Larvicidal Toxicity against Dengue and Filariasis Vectors

Mosquitoes in the larval stage are attractive targets for pesticides as mosquitoes breed in water, and thus, it is easy to deal with them in this habitat. The use of conventional pesticides, in the water sources, introduces many risks to people and environment. Natural pesticides, especially those derived from plants, are more promising in this aspect. Plants are rich in secondary metabolites which are an efficient source for natural pesticide. Nanoparticle-conjugated plant extracts increase the botanical of plant extracts and are hence attractive sources for mosquito control. The present study investigates the plant-mediated synthesis of silver nanoparticles using the Coleus aromaticus leaf extracts against dengue and filariasis mosquito vectors. Silver nanoparticle-conjugated plant extracts were characterized by Ultraviolet-Visible spectroscopy, scanning electron microscopy, Energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. The size of the silver nanoparticles was 262.7 nm. The larvicidal potential of solvent leaf extracts of Coleus aromaticus and synthesized silver nanoparticles using aqueous leaf extract against fourth instar larvae of Aedes aegypti and Culex quinquefasciatus was assessed. Larvae were exposed to varying concentrations of plant extracts and synthesized AgNPs plant extracts post 24 h; mosquito larvae showed maximum mortality in leaf extracts synthesized AgNPs against the fourth instars larvae of Ae. aegypti and Cx. quinquefasciatus. These results suggest that the synthesized AgNPs from leaf extracts have a higher larvicidal potential as compared to crude solvent extracts thus making them an effective combination for controlling dengue and filariasis vectors.

Plant-Mediated Synthesis of Silver Nanoparticles: Their Characteristic Properties and Therapeutic Applications.

Interest in “green nanotechnology” in nanoparticle biosynthesis is growing among researchers. Nanotechnologies, due to their physicochemical and biological properties, have applications in diverse fields, including drug delivery, sensors, optoelectronics, and magnetic devices. This review focuses on the green synthesis of silver nanoparticles (AgNPs) using plant sources. Green synthesis of nanoparticles is an eco-friendly approach, which should be further explored for the potential of different plants to synthesize nanoparticles. The sizes of AgNPs are in the range of 1 to 100 nm. Characterization of synthesized nanoparticles is accomplished through UV spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and scanning electron microscopy. AgNPs have great potential to act as antimicrobial agents. The green synthesis of AgNPs can be efficiently applied for future engineering and medical concerns. Different types of cancers can be treated and/or controlled by phytonanotechnology. The present review provides a comprehensive survey of plant-mediated synthesis of AgNPs with specific focus on their applications, e.g., antimicrobial, antioxidant, and anticancer activities.

Biosynthesis of silver nanoparticles using aqueous leaf extract of Thevetia peruviana Juss and its antimicrobial activities

Biosynthesizing of silver nanoparticles using microorganisms or various plant parts have proven more environmental friendly, cost-effective, energy saving and reproducible when compared to chemical and physical methods. This investigation demonstrated the plant-mediated synthesis of silver nanoparticles using the aqueous leaf extract of Thevetia peruviana. UV–Visible spectrophotometer was used to measure the surface plasmon resonance of the nanoparticles at 460 nm. Fourier Transform Infrared showed that the glycosidic –OH and carbonyl functional group present in extract were responsible for the reduction and stabilization of the silver nanoparticles. X ray diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy and Selected Area Electron Diffraction analyses were used to confirm the nature, morphology and shape of the nanoparticles. The silver nanoparticles are spherical in shape with average size of 18.1 nm. The synthesized silver nanoparticles showed activity against fungal pathogens and bacteria. The zone of inhibition observed in the antimicrobial study ranged between 10 and 20 mm.

Seaweed-synthesized silver nanoparticles: an eco-friendly tool in the fight against Plasmodium falciparum and its vector Anopheles stephensi?

Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.

Plant-mediated synthesis of silver nanoparticles using parsley (Petroselinum crispum) leaf extract: spectral analysis of the particles and antibacterial study

Synthesis of nanomaterials may involve various routes including physical, chemical and biological approaches. Here, the biological green route was chosen to prepare silver nanoparticles from silver salts to avoid the requirement of costly instruments and involvement of hazardous chemicals as well. To make the process clean and green, leaf extract of parsley (Petroselinum crispum) was used to synthesize Ag nanoparticles at room temperature. The formation of Ag-nanoparticles was monitored by UV–Vis spectroscopy. The presence of silver in the sample and its crystalline nature were verified by X-ray diffraction (XRD) analysis. The size distribution profile and particle size in the suspension were manipulated from dynamic light scattering (DLS) pattern. The shape, size and morphology of the biogenic nanoparticles were studied using high resolution transmission electron microscope (TEM). Fourier transform infra-red spectroscopy was used to detect the biomolecules responsible for reduction of silver ions. These biogenic Ag-nanoparticles showed appreciable antibacterial efficacy against three bacteria—Klebsiella pneumoniae, Escherichia coli and Staphylococcus aureus.