An Innovative Approach for the Jeevamrutha-Mediated Green Synthesis of Silver Nanoparticles and their Application in Agriculture and Biomedical Field

Green synthesis is the synthesis of nanoparticles using biological systems and is greatly beneficial because of its non-toxicity and eco-friendly behaviour. This study focuses on the green synthesis of silver nanoparticles using Aloe vera gel extract and Abelmoschus esculentus extract and its characterization and antibacterial activity. The synthesized nanoparticles were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and UV- Vis Spectroscopy. The bio-reduction of aqueous Ag+ ions by these extracts were identified by their colour change. The change in colour indicates the formation of AgNPs (Silver Nanoparticles). Silver nanoparticles showed maximum absorbance at 250nm in both Aloe vera gel extract and Abelmoschus esculentus. A peak obtained at this point confirmed the presence of AgNPs. Moreover, the synthesized silver nanoparticle showed potential antibacterial activity against the selective strains of bacteria such as Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes which were studied using the well-diffusion method. This study gives a scope for its potential applications in biomedical field.

Background and Objective: In this study, dudoa (Hydnocarpus alcalae C.DC.) leaf extract was used as a reducing and stabilizing agent in a novel one-step green synthesis of silver nanoparticles. Dudoa is an endemic plant in the province of Legazpi, Philippines and its seed oil was used as an anti-leprotic drug. Method: Therefore, the dudoa leaf extract was used to synthesize silver nanoparticles. Moreover, optimization of various parameters greatly affected the size and morphology of the synthesized AgNPs as indicated by the Ultraviolet-visible (UV-vis) spectrophotometry. The synthesized AgNPs were further characterized using spectral analyses such as XRD, EDX, SEM, FT-IR, TGA and DLS. The antimicrobial activity of synthesized AgNPs was also demonstrated. Results and Discussions: The synthesized AgNPs exhibited a diffraction pattern and a particle size ranging from 22-48 nm. The AgNPs also showed complete inhibitory and mild reactivity against representative pathogenic gram-positive (S.aureus) and gram-negative (E.coli) bacteria. Conclusion: Silver nanoparticles were successfully synthesized using H. alcalae leaf extract. Furthermore, this green synthesis approach appeared to be cost-effective, non-toxic, and eco-friendly which is a best alternative to the conventional chemical methods.

Nanoparticles are molecules in the range of 1 nm to 100 nm and they can be synthesized by physical, chemical and biological methods. Green synthesis involves the production of nanoparticles from bacteria, fungi, algae, plants and plant extracts. Plant extracts with their chemical constituents can capture the target metals from their salt solution and transform the metal particles into nanoparticles with the cellular catalysts. The present study focuses on the green synthesis of silver nanoparticles using the liquid endosperm of coconut, the coconut water (Cocos nucifera), Liquid endosperm of palm fruit (Borassus flabellifer) and coconut Toddy as the reducing agent. The bio-reduction of aqueous silver ions by coconut water is identified by its colour change. During the synthesis of silver nanoparticles, the colour of the solution changed from milky white to brown. The characterization of synthesized AgNPs (Silver Nanoparticles) was done by Fourier Transform Infrared Spectroscopy and UV-Vis Spectroscopy. The peaks obtained at 250 and 350 nm confirmed the presence of synthesized Silver Nanoparticles. The antibacterial activity of the synthesized nanoparticles was studied on Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes using disc diffusion method. The recent approach of green synthesis is quite impressive due to its eco- friendly, economical, feasible and non- toxic nature.

Nanotechnology deals with the synthesis of nanoparticles with controlled size, shape and dispersity of materials at the nanometer scale and their potential use for human well bein g. This leads to focus on “Green Synthesis” of nanoparticles which seems to be an easy, efficient and eco- friendly approach. In this study, the green synthesis of silver nanoparticles was carried out using root extract of Morinda pubescens as reducing agent. It was found that aqueous silver ions can be reduced by aqueous root extr act of Morinda pubescens to generate extremely stable silver nanoparticles in water. The silver nanoparticles (AgNPs) formation was confirmed by the colour change of the mixture and further confirmed by spectral analysis. UV-Visible spectrum of the aqueous medium containing silver nanoparticles showed a peak around 416.5 nm. FT -IR analysis confirmed reduction of Ag+ ions to Ag0 ions in synthesized silver nanoparticles. Further, the produced silver nanoparticles showed bactericidal effect against Staphylococcus aureus, Escherichia coli and Aspergillus niger. From this study concluded that the root extract of Morinda pubescens reduces Ag+ to Ag0 and enhances synthesis of silver nanoparticles with antimicrobial activity.

Sumac (Rhuscoriaria L., family Anacardiaceae) is rich in bioactive components like tannins and phenolic compounds, exhibiting antioxidant properties. Green synthesis of silver nanoparticles (SAgNP) offers eco-friendly and cost-effective production methods. In this study, the effect of Sumac nano silver particles (SAgNP) on lead pharmacokinetics was assessed. Green synthesis of silver nanoparticles involved adding 25 ml of sumac extract to 200 ml of 1 mM silver nitrate solution under hot stirring. Twenty-one male albino rats were randomly divided into three groups: lead group (60 mg/kg of lead acetate orally), crude group (100 mg/kg of crude sumac extract orally), and nano group (100 mg/kg of SAgNP orally followed by lead acetate). Results demonstrated successful SAgNP formation and significant reduction (p≤0.05) in blood lead concentration after 6 hours, suggesting SAgNP's potential in lowering lead levels. SAgNP exhibited stronger efficacy than crude extract in reducing blood lead concentrations. Green synthesis of silver nanoparticles offers a safe, cost-effective, and environmentally friendly approach with promising applications in mitigating lead toxicity.

Nanoparticle research is fascinating and getting hold of consequences due to the wide variety of applications in the biomedical field. Green synthesis of nanoparticles is a cost-effective and eco-friendly approach. It can be synthesised using fungi, algae, plant, yeast, bacteria, microbial enzymes etc. Our current research study focuses on the green synthesis of silver nanoparticles using seed extract of Cassia tora. The colour change from yellow to red colour confirms the formation of silver nanoparticles. The synthesised silver nanoparticles were characterised by Ultraviolet-Visible spectroscopy, Fourier-transform infrared (FTIR), X-ray diffraction analysis (XRD), Scanning Electron Microscopy (SEM) and antibacterial efficacy against three different strains were analysed. The surface plasmon resonance of synthesised AgNPs using Cassia tora seed extract shows maximum absorption peak at 423nm in UV-visible spectroscopy. X-ray diffraction displays the crystalline nature of synthesised AgNPs and they exhibited four distinct peaks at 36.69°, 42.92°, 63.27° and 76.46°. The particle size of synthesised AgNPs observed through SEM was found to be 55.80nm, 58.97nm, 61.06nm, 63.26nm and 64.80nm. S.aureus exhibited maximum zone of inhibition of 12mm and 13mm when treated with 25 and 50 μl of the synthesised nanoparticles. Thus, the green synthesised silver nanoparticle using Cassia tora seed extract proved to possess strong anti-bacterial activity.

The science of nanotechnology and nanoparticles is the manipulation of matter on atomic and molecular weight, the nanotechnology and nanomaterial’s refer to the particular technological goal which is precise manipulation of atom and molecules for used the fabrication process of microbial products and it is now concern to as molecular nanotechnology, it also known as the nanotechnology is science of designing, making and application of nano-structure and nanomaterials also used investigation of relationship various properties of materials with their nanometer dimensions. The exploitation of various plant materials for the biosynthesis of silver nano particles is considered a green technology. Because it does not involves any harmful chemicals. Nanotechnology field is one of the most attractive researches. The field of nanotechnology is applied to bio materials. Nanoparticles are generally considered as particles with a size up to 100 nm, that have completely new or improved properties as compared to the bulk material that they are collected based on particular characteristics such as size, distribution and morphology. Different groups of unorganized parts of the plants have been utilizing for the green synthesis of silver nanoparticles, in the present work the fresh leaves of euphorbia umbellate have been used for the synthesis of silver nanoparticles. Synthesis of AgNPs employing either microorganisms or plant extracts has emerged as an alternative approach. Silver nanoparticles is embedded with antibacterial properties because of its unique properties is considered in medical science, the main aim of work is green synthesis of silver nanoparticles using Euphorbia Umbellate leaf extract and its antibacterial activity, after the collection of sample, identification and extraction of Euphorbia Umbellate was performed the production of silver nanoparticles.

Silver nanomaterials have been integrated into industrial, biomedical and agricultural application, including biosensor, anti-microbial, anti-tumor, drug delivery, waste treatment, coated fabrics and nano fertilizer. Nanoparticle possesses unusual character due to their large surface area to volume ratio and an extraordinary catalytic activity, electronic properties, optical properties and anti-microbial activity while they are constructed in atomic level. The unique and major task in the synthesis of nanoparticle is choosing of an advanced and ecofriendly method. Nevertheless, physical and chemical methods of synthesis of nanoparticles are too expensive and environmentally unsound. In this study, the green synthesis of nanoparticle’s production methods was evaluated on the basis of variable literatures. Currently, there is a better possibility of using green synthesis of silver nanoparticles, especially a plant, bacterial and fungal production of nanoparticles which is emerging as a novel ecofriendly technique. The growth rate of bacterial culture, the extract of plant secondary metabolite and mycelial surface area of fungus are the main comprehensible mechanism in green synthesis of silver nanoparticles. The silver nanoparticles, which are produced through green biosynthesis is safe and hold a better possibility to be administered for medical and agricultural usages. Over all we found that the fungal green biosynthesis of silver nanoparticles is considered more preferable and is excellently chosen in it in industrial level production.

Abstract. Bonde S. 2011. A biogenic approach for green synthesis of silver nanoparticles using extract of Foeniculum vulgare and its activity against Staphylococcus aureus and Escherichia coli. Nusantara Bioscience 3: 59-63. We report green synthesis of silver nanoparticles from extract of Foeniculum vulgare (fennel, saunf). The synthesis of silver nanoparticles was detected by changing color from green to brown after treatment with AgNO3 (1mM) and the UV-visible spectrophotometer analysis showed the absorbance peak at about 427 nm, which indicates the synthesis of silver nanoparticles. Nanoparticle Tracking and Analysis (NTA) by LM-20 was used for multi-parameter analysis, allowing for characterization of particle size and particle distribution of silver nanoparticles synthesized from extract of F. vulgare. NTA revealed the polydispersed nanoparticles in the range of 18-83 nm. Phytosynthesized silver nanoparticles showed antibacterial activity against the Staphylococcus aureus (ATCC-25923) and Escherichia coli (ATCC-39403). The silver nanoparticles also demonstrated remarkable antibacterial activity against two human pathogenic bacteria when used in combination with commercially available antibiotics. The bactericidal activity of the standard antibiotics was significantly enhanced in presence of silver nanoparticles against pathogenic bacteria, viz. E. coli-JM-103 (ATCC-39403) and S. aureus (ATCC-25923). Silver nanoparticles in combination with vancomycin showed maximum activity against E. coli (increase in fold area 5.76. and followed by S. aureus (1.08) and Gentamicin showed the maximum activity S. aureus (2.6) while E. coli (0.96). The approach of phytosynthesized silver nanoparticles using F. vulgare appears to be cost-efficient, eco-friendly and easy alternative to conventional methods of synthesis.

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.

Chapter 1 - Green route synthesis of silver nanoparticles (Ag-NPs) and their applications

Background: Appearance of antibiotic resistance has raised the demand to find alternative therapies and modified drug delivery system of medicinal plants to treat bacterial infections.
 Objective: The aim of this study is the green synthesis and characterization of silver nanoparticles by using crude extract of Crotalaria burhia and to evaluate their antibacterial potential.
 Methods: The roots and stems of plant were used to prepare the crude extract. The phytochemical analysis of different compounds in extract was performed. 1mM AgNO3 and different concentrations of plant extract were used for the green synthesis of silver nanoparticles. The particles size and zeta potential were measured by zeta sizer while surface morphology of silver nanoparticles was observed with Scanning Electron Microscope (SEM). The antibacterial activity of silver nanoparticles was performed by 96 well microdilution plate method.
 Results: The particle size and zeta potential of optimized formulation was 92 nm and -24.8 mV. The SEM analysis showed that silver nanoparticles are irregular and spherical shape. The antibacterial activity showed that MIC value of silver nanoparticles was lower for E. coli than S. aureus.
 Conclusion: Silver nanoparticles possess potent bactericidal activity against E. coli and moderate activity against S. aureus. It had been concluded that these nanoparticles can be used against multi-drug resistant bacterial infections.

Nanotechnology has become the foremost promising and rising field of analysis as a result of its applications in numerous fields. Development of consistent and greener ways for the synthesis of nanoparticles could be a dynamic step in the field of nanotechnology. To avoid the emergence of dangerous by-products, many attempts have been made in recent years to develop environment friendly methods. “Green” synthesis is a consistent, sustainable, and environment friendly method for the synthesis of an enormous range of nanoparticles. Green synthesis is seen as an important tool to reduce the harmful effects of traditional nanoparticle synthesis methods commonly used in laboratories and industries. Nanoparticles exhibit unique chemical and physical properties that are useful in various fields. Among metallic nanoparticles, silver nanoparticles have become a research hotspot due to their wide range of applications. Silver nanoparticles are important because of their exceptional chemical, physical, and biological properties. Because of these unique characteristics, silver nanoparticles have numerous applications and are used as antifungal, antiviral, and antibacterial agents. They have an excellent catalytic effect on dye degradation, are very good antioxidants, and can be used to treat various diseases and exhibit wound-healing activities. The current review complies with the database of green synthesis of silver nanoparticles using plant extracts, bacteria, and fungi, which have potential applications in fields of science, health, textiles, food packaging, agriculture, and environment. The review also highlights the application of silver nanoparticles as antimicrobial, antibacterial, antiviral, and antifungal agents. The knowledge on silver nanoparticle production conditions, properties, molecular mechanisms, and applications will be of great help for researchers to explore more applications of nanoparticles in fields that are still untouched.

The recent research in nanoparticles synthesis field utilizes biological synthesis rather than chemical and physical methods in order to get uniform size and non-toxic of nanoparticles, further in biological synthesis the microbial synthesis is time consuming and requires sterilized conditions wherein green synthesis can overcome these drawbacks. The green synthesis of silver nanoparticles from many plant extracts finding quit attraction to many research scholars though very minute work has been done by using Hibiscus leaf extract. In this research work comparative experimental investigation is done on green synthesis of silver nanoparticles from three extracts Hibiscus leaf extract, followed by characterization was done by UV-Spectrophotometer, XRD, FTIR, AFM and SEM analysis. The silver nanoparticles of size 25-50 nm were synthesized by Hibiscus leaf extract. The silver nanoparticles were later treated with 4 different antibiotics wherein erythromycin showed three-fold increments in its efficiency.

Silver nanoparticles (AgNPs) have sparked widespread interest due to their remarkable physiochemical capabilities, and they are now being used as a beneficial tool in the biomedical field. However, typical synthesis processes generate dangerous compounds that raise environmental and safety concerns. This is one of the main reasons for choosing a greener synthesis approach. The BT5 cultivar of green tea, which is high in phenolic and flavonoid compounds and has strong antioxidant activity (IC50 ≈ 97.8 μg mL-1), was used in an eco-friendly way to produce AgNPs. The green synthesis approach was confirmed by the rapid color change (light to dark brown) of AgNO3 solution upon the addition of the BT5 extract. Several methods were performed to characterize the synthesized BT5-AgNPs, using UV-vis spectroscopy (λ max = 424 nm), FTIR, DLS, zeta potential (-39.8 ± 0.45 mV), TGA, XRD (crystalline size = 11.25 nm), and FE-SEM (35 ± 8.36 nm). BT5-AgNPs showed strong antiproliferative properties inimical to Ehrlich-Lettre ascites carcinoma cells (EAC) of the Swiss albino variety of mice model, with low-concentration treatment (1 mg kg-1) resulting in 52.15% cell growth inhibition. Fluorescence microscopy using DAPI staining revealed morphological alterations via heterochromatization and karyorrhexis. Gene expression analysis revealed upregulation of hallmark genes p53 and BAX and Bcl2 downregulation in the low- and high-concentration groups, indicating activation of the apoptotic pathway. Most likely due to cytotoxic effects and altered cellular responses, a higher dosage (5 mg kg-1) resulted in slightly lower efficacy.