Activity Of AgNPs Research Articles

Biosynthesis and Characterization of Silver Nanoparticles-Synthesized using Extracts of Mangrove Sonneratia caseolaris leaves

The bottom-up method offers the optimum ways to synthesize nanoparticles efficiently and in an environmental friendly way. The phenolic compound contained in plant extract can be used to synthesize nanoparticles. The purpose of this study was to determine the ability of Sonneratia caseolaris mangrove leaf extract to synthesize silver nanoparticles (AgNPs). Further characterization and investigation of the antibacterial activity were also scrutinized. The first stage was the extraction of mangrove Sonneratia caseolaris leaves. The second stage was biosynthesis of the silver nanoparticles using three (1, 5 and 10 mM) concentrations of AgNO3. The third stage was investigating its characteristics and its antibacterial activity. The results showed that mangrove Sonneratia caseolaris leaf extract could produce biosynthesis nanoparticles from AgNO3. The best reaction for silver nanoparticles was 10 min reaction times with a concentration of 5 mM AgNO3. In the characterization with FTIR, the peak results obtained from biosynthesis were 3431.89, 1632.43, 1508.99, 1429.92, 928.46, 706.66 and 579.37. The size of silver nanoparticles ranged from 90-200 nm. The antibacterial activity of AgNPs dominantly inhibited gram-negative bacteria Escherichia coli and Salmonella thyphimurium.

Biosynthesis of Silver Based Nanoparticles Using Plant Leaves Extracts and Their Antibacterial Activities

The emergence of antibiotic-resistant bacteria is a major global public health concern. Antibacterial agents are one of the most exciting areas for the use of nanoparticles and have shown great potential as alternative antibacterial agents due to their outstanding physical and chemical properties. The biosynthesis and antibacterial activities of Silver Nanoparticles (AgNPs) could contribute to the development of innovative antimicrobial drugs with potential for a variety of medical applications. The X Ray Diffraction (XRD) results showed that the formed particles were pure silver nanoparticles with a cubic crystal structure and granular size. Fourier-transform infrared (FTIR) also showed that functional aggregates formed, and the thumb region confirmed the presence of silver nanoparticles. In addition, we investigated the Uv-Visible and biological activity of AgNPs. A study of the biological activity of gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli, and Klebsiella pneumonia) bacteria showed the importance of nano-silver particle biosynthesis.

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.

Antibacterial activity of silver nanoparticles synthesized from Citrus aurantium and its synergistic effect of the combination of silver nanoparticles with ampicillin against Proteus mirabilis

Abstract Background: Proteus mirabilis is one of the most infectious organisms that cause a various infections involving those of the skin, wounds, and urinary tract. This study describes the synthesis of silver nanoparticles (AgNps) and using it as an antibacterial agent. Objective: To determine the activity of AgNps and synergistic effect of combination of AgNps with ampicillin (AMP). Materials and Methods: Out of 205 samples, 32 isolated were identified as P. mirabilis and determine the inhibition zone by using AgNps and its combination with AMP. The AgNps were biosynthesized by Citrus aurantium and then characterized using Ultraviolet (UV)-visible spectroscopy, X-ray diffraction (XRD) and transmission electron microscope (TEM). The antibacterial activity of AgNps was done using well diffusion agar method and the activity was evaluated by calculating the increase in the inhibition zone and reduction in the bacterial growth. Results: The synthesized AgNps was first characterized by UV-visible spectroscopy which showed a peak between 400 and 500 cm–1. The color changes from clear yellow to red or brown color indicate the formation of AgNps. The particle size of AgNps was calculated and found to be 21.24 nm by XRD. The TEM images showed the presence of very regular particles in shape of nanospheres with a particle size in the range of 10–28 nm. Different concentrations (25, 50, 75, 100 µg/mL) were used for determining the activities of AgNps and the combination of AgNps with AMP, and the result showed that the most efficient in inhibition zone was at concentration 100 µg/mL. Conclusion: This study concluded that the green synthesized AgNps from C. aurantium leaves extract have most potential as antibacterial against P. mirabilis.

Synergistic effect of synthesized silver nanoparticles combined with amoxicillin/clavulanic acid against Pseudomonas aeruginosa isolated from clinical samples

Abstract Background: Pseudomonas aeruginosa is one of the most prevalent nosocomial pathogenic microorganisms that affect and cause a life-threatening situation. Objective: The study aimed to investigate the synergistic effect of silver nanoparticles (NPs) with amoxicillin/clavulanic acid antibiotic on P. aeruginosa growth. Materials and Methods: A total of 220 clinical samples were collected. A sample has been subjected to isolation and identification by standard microbiological procedures. The extract of Citrus aurantium was used to synthesize silver NPs. The characterization of silver NPs was achieved at the University of Tehran, by using UV–visible spectrophotometry, X-ray diffraction (XRD), and transmission electron microscope (TEM). The antibacterial activity of AgNPs and combination with amoxicillin/clavulanic acid antibiotic were tested against bacteria using the agar well diffusion method. Results: Out of the 220 samples collected, 33 (15%) isolates were positive for P. aeruginosa. Highest resistance of P. aeruginosa was found to amoxicillin/clavulanic acid in percentage of 100. NPs have been characterized by a UV–visible spectrometer which revealed a broad peak at 426 cm-1. XRD showed the purity of the prepared silver NPs that the particle size was equal to 21.26 nm. TEM measurement showed the presence of sphere-like structures with sizes of 20 nm for regular particles and 40 nm for irregular particles. AgNPs, amoxicillin/clavulanic acid, and mixture (amoxicillin/clavulanic acid + AgNPs) have high inhibition activity of P. aeruginosa in concentration of 100 µg/mL and recorded 21.33 ± 3.06, 13.00 ± 0.00, and 22.00 ± 3.46 mm, respectively. Conclusion: The results supported a green synthesis approach for the synthesis of AgNPs with antimicrobial. P. aeruginosa has synergistic combinations of AgNPs with amoxicillin/clavulanic acid, with a great inhibitory effect on the growth of the bacteria.

Phyto-Synthesis and Characterization of Silver Nanoparticles Using Box-Behnken Design and Its Anti-Alternaria Activity

Alternaria alternata is a global fungal pathogen that causes symptoms such as leaf blight and seed rot resulting in economically significant yield losses in different varieties of crops. Green synthesis of nanoparticles is preferred over other methods of synthesis due to their safety, eco-friendly approach, and cost-effectiveness. Phyto-synthesis of silver nanoparticles (Ag-NPs) using seed extract of Abrus precatorious was optimized and characterized using the Box-Behnken design (BBD). Ag-NPs with a UVmax of 409.01 nm and a crystallite and particle size of 23.75 and 34.36 nm, respectively, were synthesized. In vitro anti-alternaria activity of Ag-NPs showed a concentration-dependent inhibition of the mycelia with a maximum inhibition of 54.61% at 200 ppm which was significantly different (p < 0.05) from propiconazole (1 ppm) with 100% inhibition. A scanning electron micrograph (SEM) of mycelia treated with 200 ppm of Ag-NPs showed a shrunken and shriveled mycelia while the ultrastructure of the mycelia under a transmission electron microscope (TEM) showed the alteration of the fungus cell wall and disappearance of cellular organelles compared to the control sample, while energy dispersive x-ray spectroscopy (EDX) analysis of the mycelia showed the localization of elemental Ag (0.95%) within the cell of the fungus compared to the control. The results of this study highlighted the antifungal potential of Ag-NPs against fungicide-resistant Alternaria alternata to reduce the environmental impact of synthetic fungicides.

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.

The Efficacy of Silver Nanoparticles in Combating Biofilm Formation by Uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC) is prevalent in urinary tract infections (UTIs). UPEC’s biofilm production enables it to invade and persist in the uroepithelium, leading to recurrent UTIs. The biofilm formation is associated with antibiotic resistance. To overcome this resistance, non-conventional compounds must be developed as an alternative to conventional antibiotics. Silver nanoparticles (AgNPs) are significant due to their antibacterial activity against diverse organisms. This study was done to investigate the antibacterial and anti-biofilm effects of AgNPs on UPEC. AgNPs were biosynthesized using Pseudomonas aeruginosa ATCC 27853. AgNPs were characterized using visual inspection and scanning electron microscopy. The Agar well diffusion method was employed to assess the antibacterial activity of AgNPs against UPEC isolates. The study utilized the tissue culture plate method to investigate both the biofilm and anti-biofilm properties of AgNPs. Following incubation, Ps.aeruginosa and silver nitrate (AgNO3) mixture exhibited a colour change from pale yellow to dark brown. The mean size of spherical AgNPs observed under a scanning electron microscope was 24.187 ± 8.019 nm. 130 UPECs were obtained. AgNPs exhibited antibacterial activity at a concentration of 20 µg/ml against all tested UPEC strains. Among UPEC strains that produced biofilms, a significant inhibition of 99.89 ± 0.45% was observed at a higher concentration of 512 µg/ml of AgNPs. Ps.aeruginosa produces nitrate reductase enzyme that can potentially convert AgNO3 to AgNPs. The biosynthesized AgNPs exhibit antibacterial and anti-biofilm activity against all tested UPEC strains.

Silica supported biosynthesized silver nanoparticles as effective adsorbent and photocatalyst for removal of methylene blue from water

The silica supported silver nanoparticles (Ag@SG) were prepared by wet impregnation of silica gel (SG) using different concentrations of biogenic silver nanoparticles (AgNPs; 0.25–5 mM) solution, prepared from Cicer arientinum pod extract. Among them, the Ag@SG composite prepared by using 1.25 mM AgNPs solution (Ag1.25@SG) was found to contain only Ag0 species as nanoparticles, whereas the samples prepared by higher concentrations contained Ag0 as well as Ag+ (silver oxide) species. All the Ag@SG composites including SG, exhibited good adsorption capacity for a cationic dye (methylene blue; MB) in water. However, Ag1.25@SG having only Ag0 species exhibited higher photocatalytic activity for degradation of MB under visible light irradiation as compared to other composites. The study reveals that the plasmonic Ag0 species supported on silica are catalytically more active than Ag+ species. Furthermore, the AgNPs (Ag0) in supported form exhibits much higher (∼5-fold) photocatalytic activity than unsupported AgNPs. The synergistic effect of adsorption property of silica surface and plasmonic photocatalytic activity of AgNPs in the synthesized composites was found to be effective for the removal of MB. In addition, the fine dispersion of AgNPs on internal surface of silica provides better activity for photocatalysis. The study shows that this material is a promising adsorbent as well as photocatalyst for the removal of dyes from water.

Green synthesis of silver nanoparticles using Cakile maritima seed extract: Molecular, antifungal and physiological studies

The synthesis of nanoparticles from plants is a biological process recognized to be environmentally approving, and inexpensive, which is preferred over physical and chemical processes. Plant extracts synthesize many types of metal nanoparticles with high biological activity. Because of its toxicity, aflatoxin poses a significant risk to contaminated corn kernels. However, this study focused on exploring in vitro the antifungal capacity of AgNPs biosynthesized from the seed extract of Cakile maritima on the growth of Aspergillus flavus isolated from Egyptian corn kernels. The anti-Aspergillus activity of AgNPs prepared from C. maritima seed extract was first reported. This investigation was performed to distinguish aflD, aflR, and aflP as three significant genes that contribute to the production of aflatoxin B1 cycle in A. flavus. The results gained by amplifying chosen genes by PCR for the recognition of A. flavus strains correlated significantly with TLC and HPLC outcomes. Samples that tested positive for the production of aflatoxin B1 could show amplification of the three target genes. Total phenols and flavonoids were determined from C. maritima seed extract. The quantitative evaluation of the phenolic compounds of C. maritima seed methanol extract was performed. Chlorogenic acid showed the highest amount (3250.9 μg/g dry weight). AgNPs repressed the mycelial growth and the germination of A. flavus spores more than the crude extract, AgNO3, and the fungicide compared to the negative control. The ultrastructural study of A. flavus mycelium by SEM and TEM exhibited a clear variation between untreated and treated mycelium. The treated mycelium with 10% AgPNs showed severe distortion of mycelia compared to the control, crude extract, AgNO3, and fungicide. The results showed the maximum improvement in root length, shoot length, area of leaf surface, chlorophylls, protein, and carbohydrates of the seedlings of corn were assessed at 30 ppm AgNPs.

Comparative Analysis Of Antibacterial And Antifungal Activity Of AgNPs With Conjugated Curcumin AgNPs

Silver nanoparticles (AgNPs) are potent antimicrobial agents, extensively used against a wide variety of microorganisms. Several techniques have been developed to chemically synthesize silver nanoparticles but limited their application due to their cytotoxicity and safety concerns for humans and the environment. The current study summarized the preparation of silver nanoparticles from a reaction of silver nitrate with grapefruit extract and to compare the antimicrobial activities of AgNPs and Cur-AgNPs. A natural phenolic compound having mild antimicrobial potential, curcumin was conjugated with initially synthesized silver nanoparticles (Cur-AgNPs) and characterization was performed before and after conjugation by using UV-visible spectrophotometer and Fourier Transform Infrared Spectroscopy (FTIR). The antimicrobial activity of both AgNPs and Cur-AgNPs was assessed against microbial species including gram-positive and gram-negative bacteria. The obtained results led to the conclusion that Cur-AgNPs have more antibacterial and antifungal activity than silver nanoparticles (AgNPs). The antibacterial potential of AgNPs and Cur-AgNPs was evaluated by measuring the diameter of the zone of inhibition in cm. The maximum zone of inhibition measured while using conjugated Cur-AgNPs at a concentration of 0.4mg/uL was 2cm, 1.9cm and 2.2cm against fungus, E.coli and P.aeruginosa respectively. The conjugation of curcumin to silver nanoparticles devised a new biocidal agent and lifted the industrial biomedical application of silver nanoparticles with less toxicity towards the ecosystem.

Synergistic antibacterial effect of Persicaria odorata synthesised silver nanoparticles with antibiotics on drug-resistant bacteria

For many years, combination therapies with two or more antimicrobial agents have gained interest to address the problem of emerging antibiotic resistance. Several studies have shown that the addition of AgNPs enhances the antimicrobial activity of antibiotics against resistant pathogens. However, the antibacterial activity of phytosynthesised silver nanoparticles (AgNPs) in combination with antibiotics has not been extensively studied. Therefore, this study aimed to investigate the antibacterial activity of the phytosynthesised AgNPs with different antibiotics against two common pathogenic bacteria, namely methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. A green method was used to produce AgNPs, where Persicaria odorata extract acted as a reducing and stabilising agent in the aqueous synthesis process. The production of AgNPs was verified through various analytical techniques, including ultraviolet–visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy and energy-dispersive X-ray. Notably, strong absorption spectrum corresponding to the surface plasmon resonance peaks of AgNPs was found at 436 nm, with particles ranging from 10 to 35 nm. The disc diffusion technique was used to investigate the antibacterial activity of AgNPs, both alone and in combination with antibiotics. Initially, the MRSA and P. aeruginosa showed 100 % resistance to antibiotics, especially ampicillin. However, the disc diffusion result exhibit a significant increase in the inhibition zone when ampicillin-AgNPs, cefoxitin-AgNPs and chloramphenicol-AgNPs were used in combination. In short, the findings of this study showed that AgNPs exhibit a promising synergy when used in combination with antibiotics, opening up possibilities for future combination therapies against antibiotic-resistant pathogens.

SILVER NANOPARTICLES INHIBIT INFECTIOUS BRONCHITIS VIRUS REPLICATION

Objective: Avian infectious bronchitis virus (IBV) threatens the poultry industry and causes global economic losses. The IBV is highly variable. Thus, no effective drugs are available. Objective of the present study was to evaluate silver nanoparticles against it as an antiviral agent. Methods: Silver nanoparticles (AgNPs) have been evaluated as antivirals against IBV. P. betle leaf extract biosynthesizes AgNPs from silver nitrate. UV/vis absorption, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM) have been used to characterize AgNPs. TEM indicated particle sizes of 5–30 nm, and XRD demonstrated their characteristic AgNPs structure. The antiviral activity of AgNPs was measured by the log embryo infective dose 50 (logEID50)/ml and the number of IBV genome copies. Results: XRD analysis showed a structure for AgNPs, and transmission electron microscopy showed a size of 5–30 nm for AgNPs. AgNPs at a noncytotoxic concentration inhibit the interaction between the virus and the cell, preventing the virus from entering the cell and reducing the number of IBV genome copies (per µl) in ovo by preventing the formation of the IBV RNA genome, resulting in a significant reduction in the IBV titer. Conclusion: AgNPs possess antiviral properties that inhibit IBV replication in ovo. The findings indicate that AgNPs are a promising drug candidate for treating or preventing IBV infection.

Silver nanoparticles-resistance of HeLa cell associated with its unusually high concentration of α-ketoglutarate and glutathione

Silver nanoparticles (AgNPs) is known as one of the most valuable metal nanoparticles in antibacterial and anticancer application. AgNPs-resistant bacteria has been documented, but it is unclear whether cancer cells can also escape the anti-cancer effect of AgNPs. In this study, we aimed to investigate this phenomenon and its underlying mechanism. The antibacterial activity and cytotoxicity of AgNPs were measured in the presence of HeLa cell metabolites. The status of AgNPs in the system associated with metabolites were characterized by UV-Vis, Zetasizer Nano ZS, and transmission electron microscopy. Non-targeted metabolomics was used to reveal the metabolites components that bind with AgNPs. HeLa cells were injected intraperitoneally to establish the tumor-bearing mice model, and the stability of AgNPs in mice serum was analyzed. The results manifested that HeLa cell metabolites inhibited the anticancer and antibacterial effects of AgNPs in a dose-dependent manner by causing AgNPs aggregation. Effective metabolites that inhibited the biological activity of AgNPs were stable in 100 ℃, insoluble in chloroform, containing sulfur elements, and had a molecular weight less than 1 kDa in molecular weight. There were 115 compounds bound with AgNPs. In vitro experiments showed that AgNPs aggregation occurred only when the concentration of α-ketoglutarate (AKG) and glutathione (GSH) together reached a certain threshold. Interestingly, the concentration of AKG and GSH in HeLa cellular metabolites was 10 and 6 times higher than that in normal cervical epithelial cells, respectively, which explained why the threshold was reached. Furthermore, the stability of AgNPs in the serum of tumor-bearing mice decreased by 20% (P < 0.05) compared with the healthy mice. In conclusion, our study demonstrates that HeLa cells escaped the anti-cancer effect of AgNPs through the synergistic effect of AKG and GSH, suggesting the need to develop strategies to overcome this limitation.

Eco-friendly Synthesis of Silver Nanoparticles using Bignay (Antidesma bunius) Leaves for Antibacterial Application

Background:: Foodborne pathogenic bacteria continue to become a global concern despite the advancements in food packaging technology. Silver nanoparticles (AgNPs) are widely studied in the field as they exhibit desirable inhibitory properties against foodborne pathogens. AgNPs are conventionally synthesized by toxic chemical and physical means; hence, there is a need to seek environmentally safe alternative routes for producing AgNPs. Objective:: The study aimed to synthesize AgNPs using bignay (Antidesma bunius) leaf extract and assess its antimicrobial activity against the common foodborne pathogens S. aureus and E. coli. Methods:: Bignay leaf extract was characterized using total phenolic content (TPC) assay and 2,2- Diphenyl-1-picrylhydrazyl (DPPH) assay. AgNPs were produced under optimized pH, temperature, and incubation time and were characterized using UV-Vis spectroscopy, Fourier Transform Infrared spectroscopy, and Transmission Electron Microscopy. The antimicrobial activity of AgNPs was evaluated against S. aureus and E. coli using the Resazurin Microtiter Assay (REMA). Results:: Bignay leaf extract exhibited a total phenolic content of 0.315 ± 0.015 mg GAE/mg extract and an IC50 of 36.36 ± 0.003 μg/mL, which suggests its good reducing properties. The AgNPs synthesized under reaction conditions of pH 7, 45 ºC, and 30 min showed SPR peaks in the range of 412- 426 nm. Particles were spherical with an average size of 23.72 ± 7.30 nm. FTIR analysis revealed that the phenolic compounds in the extract capped the resulting nanoparticles. AgNPs demonstrated superior inhibitory activity against S. aureus and E. coli with MIC90 values of 2.90 ± 0.03 and 3.08 ± 0.004 μg/mL, respectively. Conclusion:: The study was able to develop a green approach for the synthesis of AgNPs with antibacterial properties using bignay leaf extract.

An investigation into synthesis and characterization of Ag-nanoparticles using green chemistry, and their antibacterial properties

The quest for new nano-systems is ongoing to provide tailored nanoparticle systems for commercial purposes. The ability to manage their size and morphology leads to an advantage over other characteristics, therefore, a stable generation system is considered critical for their applications. We employed rose plant leaves extract to generate Ag-NPs via silver nitrate (AgNO3) as a basic ingredient in this study. The procedure was executed for multiple concentrations of the plant extract, as well as varying amounts of salt, and for different time periods. All of the different steps resulted in the development of Ag-NPs. The emergence of an absorption peak at 425 nm in UV-Vis spectroscopic spectra, and the presence of spherical particles visualized through SEM provided evidence of the creation of small-sized Ag-NPs. Finally, using the spread plate method, the antibacterial activity of Ag-NPs was investigated, and it was discovered that Ag-NPs exhibit high antibacterial activity against the four bacterial strains.

Green synthesis of silver nanoparticles using Sambucus ebulus leaves extract: Characterization, quantitative analysis of bioactive molecules, antioxidant and antibacterial activities

Sambucus ebulus is a well-known medicinal plant used as a traditional medicine due to its bioactive compound contents. The importance of nanotechnology has increased recently since it has effective and widespread usage areas. In this study, silver nanoparticles (AgNPs@Se) were synthesized using S. ebulus leaf extract and their structures were clarified by spectroscopic analyses including FTIR, UV–Vis, and XRD. The morphology and particle size of AgNPs@Se were determined by SEM analysis. Quantitative analysis of bioactive compounds of S. ebulus leaf extract was defined by HPLC analysis. Antioxidant activity of extract and AgNPs@Se was executed by DPPH•, ABTS•+, and FRAP assays. The antibacterial activity of AgNPs was carried out using agar well diffusion and microdilution broth methods. Quantitative analysis of bioactive compounds in S. ebulus leaf extract was established by HPLC. The average particle size of nanoparticles was calculated as 18.6 nm. Isoquercitrin was found as a major product. AgNPs@Se displayed excellent antioxidant activity, but they revealed a moderate antibacterial effect. The structure of nanoparticles was assigned as a face center cubic unit cell. Hence, nanoparticles could be a favorable agent for the pharmaceutical and food industry.

Antibacterial Efficacy and Mechanical Strength of Direct Dental Composite Resins with Integrated Metal and Metal Oxide Nanoparticles: A Systematic Review of In-Vitro Studies

The present systematic review aimed to evaluate the antibacterial efficacy and mechanical strength of direct dental composite resins with integrated metal/metal oxide nanoparticles (NPs). A review was performed using different electronic databases employing MeSH terms for identifying relevant published literature, without any restrictions on language and date of publication. The antibacterial activity of metal/metal oxide NPs-incorporated composites for the prevention of secondary caries was the primary outcome, whereas the mechanical strength was designated as the secondary outcome. 6 studies used varying amounts of silver (AgNPs); 5 studies used zinc oxide (ZnO-NPs); 1 study used Ag-doped ZnO-NPs. Four studies found a statistically significant (p &lt; 0.05) antibacterial activity of varying amounts of ZnO-NPs, five studies found a statistically significant (p &lt; 0.05) antibacterial activity of AgNPs, two studies reported a statistically non-significant (p &gt; 0.05), however greater antibacterial activity, by the incorporation of AgNPs. All included studies reported that the mechanical strength of the composites was not compromised by the addition of either ZnO-NPs or AgNPs. Metal/metal oxide-modified direct dental composite resins resulted in improved antibacterial efficacy without compromising their mechanical strength as compared to non-modified composite resins. However, it is imperative to determine an equilibrium between the mechanical features and antibacterial activity of these materials, and more in vivo investigations are recommended in this aspect.

Amomum subulatum Fruit Extract Mediated Green Synthesis of Silver and Copper Oxide Nanoparticles: Synthesis, Characterization, Antibacterial and Anticancer Activities

This research presents a straightforward, effective, and eco-friendly method for the production of silver nanoparticles (AgNPs) and copper oxide nanoparticles (CuONPs) using the dried fruit of Amomum subulatum as a reducing, stabilizing, and capping agent. The formation of AgNPs and CuONPs is supported by the presence of a surface plasmon resonance band (SPR) at 440 nm for AgNPs and 245 nm for CuONPs. Additionally, the identification of specific biomolecules responsible for the synthesis of AgNPs and CuONPs was confirmed through FTIR spectra analysis. The Transmission electron microscope (TEM) images demonstrated that AgNPs and CuONPs had spherical shapes, with mean particle diameters of 20.6 nm and 24.7 nm, respectively. X-ray diffraction and selected area electron diffraction (SAED) analyses provided evidence of the crystalline nature of the synthesized AgNPs and CuONPs. Additionally, the presence of silver and copper elements was observed through energy-dispersive X-ray spectroscopy (EDS) analysis. Furthermore, the antibacterial activity of AgNPs was found to be superior to that of CuONPs against human pathogens such as Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The cytotoxic activity of the biosynthesized nanoparticles (NPs) was evaluated in vitro against human cervical cells (HeLa) and human breast cells (MCF-7). In MCF-7 cells, the IC50 value for AgNPs was estimated to be 39.79 µg/mL, while that of CuONPs was 83.89 µg/mL. In HeLa cells, the IC50 value for AgNPs was 45.5 µg/mL, and for CuONPs, it was 97.07 µg/mL. For the first time, an eco-friendly method for the synthesis of AgNPs and CuONPs from fruit extract of Amomum subulatum has been discussed along with their comparative evaluation study. These results highlight the promising applications of the eco-friendly synthesized AgNPs and CuONPs as effective agents against microbial infections and potential candidates for cancer therapy.

A COMET ASSAY FOR CANDIDA GLABRATA INFECTION AND TREATMENT BY PENICILLIUM CHRYSOGENUM - DERIVED AgNPs

The colonies of C. glabrata were described, which morphology of isolated on sabouraud dextrose agar with chloramphenicol. Biosynthesis of nanoparticles is of great importance since they are highly involved in various medical and biological applications. The current study aims to produce Penicillium chrysogenum - derived AgNPs to be used to treat Candida glabrata. Nanoparticles were formed, the results of which was observed through UV-visible spectrophotometry. Therefore, the surface morphology and particles size of AgNPs were assessed using the scanning electron microscope (SEM). The atomic force microscopy (AFM) confirmed that the average diameter of AgNPs was 18 nm which is appropriate to be used to deliver Penicillium chrysogenum to the Candida infected cells. The antifungal activity of AgNPs against C. glabrata was investigated in the serum of 15 mice. The mice were divided into four groups was examined after 21 days. A comet assay described procedure that sensitive measurement and permits reproducible of DNA repair and DNA damage using C. glabrara infection and treatment by Penicillium chrysogenum - derived AgNPs. This combination of assay with affected C. glabrara in DNA repaired and the extensive range of obtainable fungal molecular biology apparatuses can donate to light important devices of genome.