Concentrations Of AgNPs Research Articles

Antimicrobial Activity of Hydrophilic Sealants incorporated with Green Synthesized Silver nanoparticles-An invitro Study

Background: Dental caries formation is highly prevented by applying pit and fissure sealant but was associated with microleakage and secondary caries formation. Aim and Objectives: To synthesize novel pit and fissure sealant with green synthesized silver nanoparticles and evaluation of antibacterial activity against Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans. Materials and Methods: Green synthesis of silver nanoparticles was done using beetroot, characterized using FTIR (Fourier transform infrared), EDAX (Energy Dispersive X-ray Analysis), and Scanned Electron Microscope Analysis. A novel pit and fissure sealant was made by incorporating synthesized Ag nanoparticles and hydrophilic nature from Ultra seal XT Hydro. Using amoxicillin as a control, an agar well diffusion method was used to conduct an antimicrobial test for a new sealant against Staphylococcus aureus, Streptococcus mutants, Enterococcus faecalis, and Candida albicans in Muller Hinton Agar for each organism. Result: Zone of inhibition was measured, showing statistically significant antimicrobial activity against Streptococcus mutans with the ZOI value at concentration of Ag nanoparticles in sealant material. Conclusion: Novel Hydrophilic pit and fissure sealant with Ag nanoparticles are potentially antibacterial against the cariogenic microorganism. Thus, it can be utilized for the better efficiency of topical pit and fissure sealant preventive therapy.

Assessment of possible potential toxicity risks in albino mice exposed to amine coated silver nanoparticles

Nanoparticles have a wide range of physiochemical properties that can harm many organs, tissues, enzymatic and hormonal activities. Throughout the world, silver nanoparticles (AgNPs) are frequently used in consumer products. The aim of the current study was to synthesize the AgNPs and to investigate their impact on hormones, antioxidant enzymatic activities, and histopathology of the liver of albino mice. The precursor salt silver nitrate and the reducing and capping agent triethylamine were used to synthesize silver nanoparticles. SEM analysis indicated particles ranged between 10–20 nm. The EDX analysis indicated distinct peaks, which illuminated the crystalline, spherical, and face-centred cubic structure of the silver particles being analyzed. Further, the albino model showed that increasing the concentration of AgNPs increased the level of plasma cortisol, T3 and T4. Catalase (CAT), Superoxide Dismutase (SOD), and Glutathione S-Transferase (GST) activities increased at 5 mg/kg but decreased dramatically at 50 mg/kg, whereas Glutathione (GSH) activities and lipid peroxidation (LPO) levels increased with increasing AgNPs concentration. Furthermore, AgNPs caused neutrophilic and lymphocytic infiltration, central vein damage, and hemorrhage in albino mouse liver at low concentrations (5 mg/kg). High concentrations of AgNPs (50 mg/kg) caused the formation of pknotic nuclei, pyknosis, apoptosis, and vacuolation. The study concluded that AgNPs have dose-dependent toxicity that alters stress hormones, T3 and T4, antioxidant enzymatic activities, and produces some histopathological alterations.

Green Synthesis Silver Nanoparticles Using Sembung (Blumea balsamifera) Leaf Extract as an Antibacterial and Antioxidant

Silver Nanoparticles essentially focuses on the synthesis of nano-sized particles produced through chemical, physical and biological processes, which contribute significantly to the control of plant and animal diseases and have shown considerable promise in improving the quality of living conditions and human health. Currently, silver nanoparticles (AgNP) have shown their potential as an alternative antibacterial and antioxidant agent in many studies. The method for making silver nanoparticles, namely Green synthesis, involves the use of plants for the synthesis process of various types of nanoparticles. Green synthesis has the advantages, namely that the method is simple, environmentally friendly, non-polluting, antitoxic and cost-effective. The aim of this research is to determine the antibacterial and antioxidant activity of AgNPs. In this research, the nanoparticle solution was visually determined by the yellow-brown color change. In the spectrophotometer absorption spectrum appears at a wavelength of 425 nm. The results of determining the size distribution of silver nanoparticles using PSA show that the particle size distribution obtained has an average value of 40.5 nm and 59.6 nm for silver nanoparticles for AgNO3 concentrations of 1 mM and 2 mM, respectively. FTIR measurements are used to determine the presence of bioactive molecules that may be responsible for the stabilization that acts as a capping agent. Absorption spiked at 3.280; 2.919; 1.583; 1.379; 1.239 and 1.068 cm−1 were determined for sembung leaf extract, while silver nanoparticles showed an absorption spike at 3.368; 2.850; 1.594; 1.369; 1.244 and 1.108 cm−1. The results of XRD analysis of AgNP show that it has been successfully synthesized which can be seen from the formation of a narrow peak indicating the crystalline nature of the nanoparticles formed. The results of TEM analysis of AgNPs in this study are mixed shapes such as spherical, hexagonal and triangular shapes of silver nanoparticles. The antibacterial activity test of silver nanoparticles with sembung leaf extract with varying concentrations of AgNO3 solution was successful as indicated by the formation of an inhibition zone for Eschericia coli and Staphylococcus aureus bacteria. The results show that the antioxidant activity of AgNPs shows that the percentage of inhibition increases as the concentration of AgNPs increases from 100 to 500 ppm and ascorbic acid increases from 1 to 5 ppm.

Synthesis of Silver Nanoparticles Using Aggregatimonas sangjinii F202Z8T and Their Biological Characterization.

The aim of this study is to describe the general features and eco-friendly biosynthesis of silver nanoparticles (AgNPs) from the marine bacterium Aggregatimonas sangjinii F202Z8T. To the best of our knowledge, no previous study has reported the biosynthesis of AgNPs using this strain. The formation of AgNPs using F202Z8T was synthesized intracellularly without the addition of any disturbing factors, such as antibiotics, nutrient stress, or electron donors. The AgNPs were examined using UV-vis spectrophotometry, transmission electron microscopy, energy-dispersive X-ray spectroscopy, nanoparticle tracking analysis, and Fourier transform infrared spectrometry. The UV-vis spectrum showed a peak for the synthesized AgNPs at 465 nm. The AgNPs were spherical, with sizes ranging from 27 to 82 nm, as denoted by TEM and NTA. FTIR showed various biomolecules including proteins and enzymes that may be involved in the synthesis and stabilization of AgNPs. Notably, the AgNPs demonstrated broad-spectrum antibacterial effects against various pathogenic Gram-positive and Gram-negative bacteria, including Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. The minimum inhibitory concentrations and minimum bactericidal concentrations of the F202Z8T-formed AgNPs were 80 and 100 µg/mL, 40 and 50 µg/mL, and 30 and 40 µg/mL against E. coli, B. subtilis, and S. aureus, respectively. This study suggests that A. sangjinii F202Z8T is a candidate for the efficient synthesis of AgNPs and may be suitable for the formulation of new types of bactericidal substances.

Correction: Antibacterial activities of GO–Ag nanocomposites with various loading concentrations of Ag nanoparticles

Correction: Antibacterial activities of GO–Ag nanocomposites with various loading concentrations of Ag nanoparticles

The Antibacterial Activity of Biosynthesized Silver Nanoparticles from Tribulus terrestris Against Pseudomonas aeruginosa

The current study’s goal is to employ Tribulus terrestris aqueous floral extracts to synthesize silver nanoparticles (AgNPs) and test their antibacterial efficacy against Pseudomonas aeruginosa (P. aeruginosa) isolated from otitis externa in dogs. Biological nanoparticle synthesis is gaining popularity over chemical and physical processes due to its cost-efficiency and environmental friendliness. Silver nanoparticles were made by mixing Tribulus terrestris plant extract with 1 mM silver nitrate (AgNO3) solution (AgNPs). UV-Visible spectrophotometry revealed the biosynthetic nanoparticles’ maximum absorbance peak at wave lengths (410nm). The SEM was spherical and homogenous in shape, with a size range of 20 to 25 nm. The XRD indicated that the size of AgNPs was 50.21 nm. EDS was utilized to determine the presence of silver element. The AFM revealed the three-dimensional structure of silver nanoparticles with a diameter of 60.17 nm on average. The Zeta potential of the particle size analyzer was 45 mV. It was observed that as the concentration of AgNPs Increased, so did the size of the inhibition zone; (150μg/ml) exhibited a larger inhibition zone (32mm) than when using concentrations of 100μg/ml, 50μg/ml, and 25μg/ml, respectively. In conclusion, biosynthesized AgNPs generated from Tribulus terrestris demonstrate potent antibacterial activity against Pseudomonas aeruginosa isolated from otitis externa in dogs.

Effects of Silver Nanoparticles on Growth of E. coli: A Study Examining Various Antibiotic Factors

Nanomedicine, an emerging and revolutionary scientific field, warrants greater scientific investigation on the antibacterial applications of AgNPs; hence, this research serves to assess AgNPs’ antibacterial effectiveness on the growth of E. coli while establishing the antibiotic’s optimal conditions for drug delivery. The hypothesis expects that optimal drug delivery of AgNPs will occur at higher concentrations of AgNPs and neutral pHs. To demonstrate this, 1:10 serial AgNP dilutions were placed in E. coli cultures and were treated with the varying environmental factors of concentration and pHs. The results supported our hypotheses with the exception of our pH hypothesis, for the data showed that having a basic pH increased the efficiency of the nanoparticles for all concentrations, except for the 500 µg/L concentration. Nevertheless, higher concentrations of nanoparticles have the highest and fastest increases in their zones of inhibitions. The concentration and pH experiments yielded statistical significance. With nanomedicine’s ability to diagnose, detect, and deliver drugs, its research applications are endless, proving it has a significant impact in the fields of cancer drug delivery, E. coli toxicity, and ectopic pregnancies, and ultimately, having the potential to save over two million lives every year.

Green Synthesis of Silver Nanoparticles from Phyllanthus emblica (Indian Gooseberry) for Potent Antimicrobial Efficacy

Nowadays cost-effective and environmentally friendly technologies for nanomaterial synthesis have gained attention in the biosynthesis of nanoparticles. The present study is focused on synthesizing silver nanoparticles using Phyllanthus emblica for a green approach. UV-Vis Spectrophotometry, XRD, SEM, and FTIR were used to characterise the synthesised silver nanoparticles. It was determined that spherical shaped nanoparticles by SEM examination, which revealed that the average particle size was 20 nm. Antibacterial activity of AgNPs analyzed with the help of Staphylococcus aureus, Vibrio cholerae, Pseudomonas auriginosa, and Bacillus subtilis bacteria, and the result shows that a higher concentration of AgNPs is increasing as well as a zone of inhibition increased.

Enhanced reddish-orange luminescence from Sm3+/Ag co-doped barium zinc borophosphate glasses: Structural and Judd-Ofelt analysis

We report the synthesis and optical response of Sm3+/Ag nanoparticles (NPs) co-doped glasses through melt quenching method. TEM analysis confirmed Ag NP formation, and the diverse functional groups were confirmed through FTIR studies. The Judd-Ofelt (JO) parameters are calculated using JO theory from absorption spectra. The PL spectra were recorded under 402 nm excitation and they show four PL bands in the visible range. The PL spectra are utilized to obtain radiative parameters to claim their utility in visible laser applications. The dominant emission color was obtained by using the CIE color chromaticity diagram. The excited state lifetime values were estimated through decay curve fitting method. All the obtained results are discussed in detail based on Ag NP concentrations.

Down-conversion emission of Er3+ doped sulfophosphate glass: The role of TiO2 and Ag nanoparticles co-embedment

In this study, Er3+-doped sulfophosphate glasses containing titanium nanoparticles (TiO2 NPs) with 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05 mol% of silver (Ag) nanoparticles (AgNPs) were synthesized using the melt-quenching technique. The impact of AgNPs on the physical and structural characteristics, optical absorption and emission features, and photocatalytic activity of the glasses were investigated. The density and molar volume of the glasses were determined. Transmission electron microscopy (TEM) was used to study the existence of both AgNPs and TiO2 NPs in the glass matrix. The absorption spectra of the glasses revealed several bands of absorption in the UV–Vis–NIR region, with peaks at 1534, 977, 795, 650, 544, 520, 487, 450, 406, 378, and 364 nm. The SPR peaks of silver were observed at 553 and 588 nm, while those of TiO2 NPs were located around 409 and 849 nm. The intensity of emission was found to be enhanced by increasing the concentration of AgNPs. According to the findings of Judd-Ofelt theory, the system containing of 0.04 mol% of AgNPs has also the optimal performance which can be applied to the function of a broadband amplifier by having a high emission cross section of 70.18 × 10−22 cm2. Finally, the photocatalytic performance of the glasses was evaluated by conducting a degradation experiment with methylene blue (MB). The results validated their light-activated self-cleaning properties in the presence of Ag/TiO2 NPs.

An intrusion and environmental effects of man-made silver nanoparticles in cold seeps

Silver nanoparticles (AgNPs) are among the most widely used metal-based engineered nanomaterials in biomedicine and nanotechnology, and account for >50 % of global nanomaterial consumer products. The increasing use of AgNPs potentially causes marine ecosystem changes; however, the environmental impacts of man-made AgNPs are still poorly studied. This study reports for the first time that man-made AgNPs intruded into cold seeps, which are important marine ecosystems where hydrogen sulfide, methane, and other hydrocarbon-rich fluid seepage occur. Using a combination of electron microscopy, geochemical and metagenomic analyses, we found that in the cold seeps with high AgNPs concentrations, the relative abundance of genes associated with anaerobic oxidation of methane (AOM) was lower, while those related to the sulfide oxidizing and sulfate reducing were higher. This suggests that AgNPs can stimulate the proliferation of sulfate-reducing and sulfide-oxidizing bacteria, likely due to the effects of activating repair mechanisms of the cells against the toxicant. A reaction of AgNPs with hydrogen sulfide to form silver sulfide could also effectively reduce the amount of available sulfate in local ecosystems, which is generally used as the AOM oxidant. These novel findings indicate that man-made AgNPs may be involved in the biogeochemical cycles of sulfur and carbon in nature, and their potential effects on the releasing of methane from the marine methane seeps should not be ignored in both scientific and environmental aspects.

Inhibitive determination of organophosphate pesticides using acetylcholinesterase and silver nanoparticle as colorimetric probe

Accurate and real-time detection of pesticides is needed to ensure food safety and ecosystem protection. A biosensor was developed to determine organophosphate pesticides using acetylcholinesterase (AChE) and silver nanoparticle (AgNP) immobilized on the alginate-chitosan film matrix. The sensing principle is based on organophosphate pesticides (OP) inhibiting AChE activity. AChE hydrolyzes acetylthiocoline (ATCh) to thiocholine (TCh) and acetic acid (AA). The -SH group on TCh induces AgNP aggregation, resulting in fading of the film's brownish-yellow color. The presence of OP in the sample inhibited AChE activity, leading to a decrease in TCh and color fading. The biosensor response is determined by measuring the Red Green Blue (RGB) value of the film. The biosensor offers rapid detection directly in-situ and real time without the use of sophisticated instruments, with optimal measurement conditions of pH 7, incubation time of 1 minute, and concentrations of AgNP, ATCh, and tris-HCl buffer of 10 μg/mL, 50, and 7 mM, respectively. Biosensors have excellent sensitivity, reproducibility, and selectivity. Measurement of OP levels in nine vegetable samples revealed that the proposed colorimetric probe's results agreed well with the GC result as the reference method. Therefore, this method can be applied in monitoring food and environment OP levels.

Effect of the addition of silver nanoparticles on the mechanical properties of an orthodontic adhesive

ObjectivesThis study evaluated the effects of adding silver nanoparticles on the shear bond strength, microhardness, and surface roughness of orthodontic adhesives. Material and MethodsFifty upper premolars were randomly allocated to five groups (n = 10). Orthodontic brackets were bonded with silver nanoparticle (AgNP)-modified adhesives (1 %, 0.5 %, 0.1 %, 0.05 %), and conventional adhesive was used as a control. The shear bond strength was recorded using a universal testing machine, and the adhesive remnant index was evaluated using a stereomicroscope. Ten discs of each adhesive were subjected to the microhardness and surface roughness tests. The Vickers microhardness values were measured under a constant load of 100 g for 30 s using a microhardness tester. The samples were analyzed using a surface profilometer, and the arithmetic average roughness was used as the measurement parameter. Data were analyzed using one-way analysis of variance and chi-square tests. A significance level of 5 % was considered significant. ResultsAgNP concentration > 0.1 % significantly reduced the shear bond strength (p < 0.05). At higher AgNP concentration, the bonding failure pattern occurred mainly at the bracket-resin interface. The Vickers microhardness increased with increasing concentration, and significant differences were observed between the group with 1 % AgNP and the other groups (p < 0.05). The average roughness values were similar between the groups with AgNP concentrations > 0.1 % (p > 0.05). ConclusionThe incorporation of AgNP into an orthodontic adhesive has the potential to decrease the shear bond strength while increasing the microhardness and surface roughness.

Biopolymeric nanofibrous scaffolds of poly(3-hydroxybuthyrate)/chitosan loaded with biogenic silver nanoparticle synthesized using curcumin and their antibacterial activities

The increasing prevalence of multi-drug resistant bacteria poses a significant threat to public health, especially in wound infections. Developing new bactericidal agents and treatment strategies is crucial to address this issue. In this study, biopolymeric nanofibrous scaffolds containing green-synthesized silver nanoparticles (AgNPs) with curcumin (CUR) were evaluated as antimicrobial materials for wound healing therapy. Firstly, CUR was utilized to synthesize AgNPs, which were then analyzed using various analytical methods. The microstructural analysis revealed that the biogenic AgNPs, which had a spherical shape and an average size of 19.83 nm, were uniformly anchored on PHB/CTS nanofibers. Then, the AgNPs with various content (0.25–1%wt) were incorporated into PHB/CTS matrix to enhance its wettability, thermal and bactericidal behaviors. The nanofibrous scaffolds were characterized by FT-IR, FE-SEM, TGA analysis and water contact angle measurement. Overall, the addition of CUR-AgNPs to the PHB/CTS matrix led to a reduction in fiber diameter, enhanced hydrophilicity and improved thermal properties. Additionally, antibacterial activity against Staphylococcus aureus and Escherichia coli was performed on samples of AgNPS and PHB/CTS/CUR-Ag. The synthesized AgNPs showed antibacterial activity against both microorganisms, especially against S. aureus. Higher concentrations of AgNPs in nanofibers led to a significant reduction in bacterial colony formation. The results displayed that PHB/CTS/CUR-AgNPs nanofibrous scaffolds could be a promising material for the biomedical applications such as wound healing.

ITRAQ-based quantitative proteomic analysis of the antibacterial mechanism of silver nanoparticles against multidrug-resistant Streptococcus suis.

The increase in antibiotic resistance of bacteria has become a major concern in clinical treatment. Silver nanoparticles (AgNPs) have significant antibacterial effects against Streptococcus suis. Therefore, this study aimed to investigate the antibacterial activity and mechanism of action of AgNPs against multidrug-resistant S. suis. The effect of AgNPs on the morphology of multidrug-resistant S. suis was observed using scanning electron microscopy (SEM). Differentially expressed proteins were analyzed by iTRAQ quantitative proteomics, and the production of reactive oxygen species (ROS) was assayed by H2DCF-DA staining. SEM showed that AgNPs disrupted the normal morphology of multidrug-resistant S. suis and the integrity of the biofilm structure. Quantitative proteomic analysis revealed that a large number of cell wall synthesis-related proteins, such as penicillin-binding protein and some cell cycle proteins, such as the cell division protein FtsZ and chromosomal replication initiator protein DnaA, were downregulated after treatment with 25 μg/mL AgNPs. Significant changes were also observed in the expression of the antioxidant enzymes glutathione reductase, alkyl hydroperoxides-like protein, α/β superfamily hydrolases/acyltransferases, and glutathione disulfide reductases. ROS production in S. suis positively correlated with AgNP concentration. The potential antibacterial mechanism of AgNPs may involve disrupting the normal morphology of bacteria by inhibiting the synthesis of cell wall peptidoglycans and inhibiting the growth of bacteria by inhibiting the cell division protein FtsZ and Chromosomal replication initiator protein DnaA. High oxidative stress may be a significant cause of bacterial death. The potential mechanism by which AgNPs inhibit S. suis biofilm formation may involve affecting bacterial adhesion and interfering with the quorum sensing system.

Antibacterial activities of GO–Ag nanocomposites with various loading concentrations of Ag nanoparticles

Antibacterial activities of GO–Ag nanocomposites with various loading concentrations of Ag nanoparticles

Developing an analytical method for quantification of trientine based on modified silver nanoparticles

Trientine or (N,N´-bis(2-aminoethyl)-1,2-ethanediamine (TETA) is a copper chelator and used in Wilson’s disease, is aliphatic amine that does not have UV absorbing groups. In this study, the modified silver nanoparticles (AgNPs) by sodium lauryl sulfate have been used to develop an analytical method for quantification of TETA. Different concentrations of TETA were added into a particular concentration of AgNPs and absorbance of each sample was measured at 397 nm under the optimal conditions which include pH, time, salt and AgNPs volume. It was optimized by a design of experiments using response surface methodology. Then, the calibration curve was obtained based on the concentrations of TETA solution versus decrease in the absorbance of AgNPs. Selectivity of the developed method was performed in plasma and presence of common cations i.e. copper, zinc and ferrous. Under optimum conditions, linear range of this method was between 10 and 40 ng.mL− 1 with correlation coefficient (R2) of 0.996 with limit of detection and quantification of 3 ng.mL− 1 and 10 ng.mL− 1, respectively. Selectivity of established method in presence of cations eliminated by diluting because of high sensitivity of the established analytical techniques based on AgNPs. This method is suitable and low costing for quantification of TETA and does not require high equipment.

Evaluation of Physical Properties of Denture Base Resins Containing Silver Nanoparticles of Aloe barbadensis Miller, Morinda citrifolia, and Boesenbergia rotunda and Its Anti-microbial Effect: An In Vitro Study.

Introduction The denture bases fabricated from polymethylmethacrylate (PMMA) have some disadvantages, such as surface prone to microbial growth and biofilm accumulation, which contributes to the onset and dissemination of infections among denture wearers. Therefore, the purpose of this in vitro study was to evaluate the flexural strength, hardness, and antimicrobial effect of denture base resin incorporated with 0.05% and 0.1% silver nanoparticles (AgNPs) of Aloe barbadensis miller (aloe vera), Morinda citrifolia (noni), and Boesenbergia rotunda (finger root). Materials and methods A total of 84 PMMAsamples were used and were divided into three groups. Flexural strength tests were performed on Group 1 PMMAblocks. Group 2 involved hardness testing of PMMAblocks, whereas Group 3 involved antimicrobial activity. Each group was subsequently split into seven subgroups with differing concentrations of AgNPs: Sub Group 1: control (no AgNPs),Sub Group 2: 0.05% aloe vera AgNPs, Sub Group 3: 0.1% aloe vera AgNPs, Sub Group 4: 0.05% noni AgNPs, Sub Group 5: 0.1% of noni AgNPs,Sub Group 6: 0.05%finger root AgNPs, and Sub Group 7: 0.1% finger root AgNPs.The flexural strength was evaluated usinga universal testing machine (Instron 8801). Surface hardness was measured using a Vickers tester (Tukon 1102). For the antimicrobial activity analysis, the samples were incubated in a suitable culture broth containing Candida albicans for 24 hours. Microbial colony count (colony-forming unit (CFU)/mL) was estimated to evaluate the microbial adhesion to the surface of the denture base materials. Statistical analysis The flexural strength, hardness, and CFU between the groups were analyzed using one-way analysis of variance (ANOVA) followed by multiple comparisons with Tukey's honest significant difference (HSD) test (α=0.05). The level of statistical significance was determined at p<0.05. Results It was observed that the mean flexural strength was maximum in PMMA incorporated with 0.05% of aloe vera AgNPs and least in PMMA incorporated with 0.1% noni AgNPs. It was seen that a steady loss in flexural strength is observed from 0.05% to 0.1%. The mean hardness was maximum in PMMA incorporated with 0.1% of noni AgNPs and least in PMMA incorporated with 0.05% aloe vera AgNPs. It was also found that the hardness was directly proportional to the number of nanoparticles. With an increase in the weight percentage of nanoparticles, a steady increase in hardness was seen in all the test groups. In our study, the results showed that finger root 0.1% showed the least CFU with a significant reduction of C. albicans adherence; therefore, it indicates higher anti-fungal activity. Aloe vera 0.05% showed the lowest inhibition of C. albicans,suggesting the least anti-fungal activity. Conclusion Within the limitations of this study, It can thus be concluded that the addition of AgNPs incorporated with plant extracts of Aloe barbadensis miller (aloe vera), Morinda citrifolia (noni), and Boesenbergia rotunda (finger root) can alter the flexural strength, hardness, and microbial adhesion of PMMA. In our study, it can be concluded that flexural strength increases with the addition of AgNPs of 0.5% concentration after which a steady loss is seen. However, the hardness and antimicrobial activity increased with an increase in the concentration of AgNPs in all three plant extracts.

Green synthesis of silver nanomaterials and evaluation of their antibacterial and antioxidant effectiveness in chicken meat

Nanomaterials, chiefly silver nanoparticles (AgNP), are widely used in many commercial products, including medical commodities, food packaging and cosmetics. The goal of this research was to establish a cost-effective and environmentally safe approach to synthesize AgNP using turmeric powder. The reduction of silver ions resulted in an alteration of the turmeric extract color from yellow to brown after 24 h of reaction. The characterization of AgNP was accomplished by UV–vis spectroscopy, energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The prominent peak of AgNP colloid in a UV–vis spectrum appears at 444 nm. EDS mapping showed a potent signal of the silver element. According to TEM, most of the synthesized AgNP was spherical with an average size of 23 ± 0.49 nm. Moreover, FTIR test proved the presence of organic constituents in the AgNP colloid. The green AgNP exhibited significant (P ≤ 0.05) antibacterial activities with a 2-log CFU reduction of a Salmonella Typhimurium and Salmonella Enteritidis cocktail in chicken meat after a 1-day direct exposure to 6, 12, and 18 μg/mL of AgNP. The phytoconstituents on the surface of the AgNP exhibited good antioxidant activities by scavenging DPPH and ABTS radicals. Moreover, the nanoparticles had a higher antioxidant capacity compared to standard ascorbic acid solution, especially at 12 and 18 μg/mL of AgNP concentrations. These outcomes indicate that AgNP coated with phyto-constituents possess powerful bioactivities by inhibiting the growth of food pathogenic bacteria and, simultaneously, conferring antioxidant capability.

Green Synthesis of Silver Nanoparticles by Cardaria draba and Evaluation of its Insecticidal Effect on Schizaphis graminum

Schizaphis graminum one of the main pests of the wheat crop, causing direct and indirect damage to the growth and yield of the crop. The biosynthesis of nanoparticles using plant extracts is the most recent and workable application for pest control. This study was conducted to know the potential activity of insecticidal of synthesized silver nanoparticles (AgNPs) using plant leaf extracts of Cardaria draba. Synthesis was confirmed firstly by visual observation and then by UV-Vis spectrophotometer where The peak was recorded at 428 nm, The results of XRD technique of the colloidal solution confirmed the crystalline nature of the silver nanoparticles. FTIR analysis spectrum showed different types of functional groups which played crucial role in the biosynthesis of AgNPs. FESEM analysis determined the size and shape of AgNPs where average size was 85nm with roughly circular or spherical in shape. Different concentrations of AgNPs were prepared and tested on mortality of the stages of S. graminum, The highest mortality of adults and nymphs recorded 52.99 and 57.13% respectively at the high concentration 100 ppm compared with 4.79 and 5.87% respectively in the control treatment after 3 days from exposure time. In addition to statistically significant differences was in adult and nymph mortality between concentrations. The results suggested that using green biosynthesis of silver nanoparticles can be used as an effective way in the control S. graminum on wheat crops.