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Leishmania is the primary cause of a significant public health problem known as leishmaniasis in Iran. Pentavalent antimonial chemicals are commonly used for the treatment of leishmaniasis. However, these drugs exhibit a number of adverse effects, including drug resistance, lack of specificity, poor responsiveness, toxic effects, inconvenient injections, tissue damage, and high cost. The present study aimed to prepare and evaluate the efficacy of green-synthesized silver nanoparticles (Ag-NPs) against Leishmania infantum and Leishmania tropica in vitro. The 2, 5-Diphenyl Tetrazolium Bromide (MTT) assay was used to assess the toxicity of Ag-NPs derived from ginger extract on macrophage cells. The apoptotic potential of promastigotes caused by Ag-NPs was evaluated using the flow cytometry method. According to our findings, the proliferation of L. infantum and L. tropica, promastigotes are significantly decreased by increasing doses of NPs. The most effective doses of nanoparticle were 80 and 40 ppm after 48 and 72 hours of incubation, respectively, while doses of 0.312 and 0.156 ppm after 24 and 48 hours of incubation had the least effect on the growth and activity of L. infantum and L. tropica promastigotes. For the promastigotes of L. infantum and L. tropica, the flow cytometry test revealed that Ag-NPs-induced programmed cell death in promastigotes of L. infantum and L. tropica demonstrated 67.1% and 41.9% of apoptosis, respectively. The half-maximal inhibitory concentration for NPs against L. infantum and L. tropica were 4.54 and 4.22 ppm, respectively, based on the MTT assay. The higher concentrations of NPs (e.g., 80 ppm) led to more lethality of promastigote. In conclusion, Ag-NPs exhibited good in vitro anti-leishmanial activity against L. infantum and L. tropica promastigotes. [ABSTRACT FROM AUTHOR]

Rhazya stricta is a major medicinal species used in indigenous medicinal herbal medications in South Asia, the Middle East, Iran, and Iraq to treat a variety of ailments. The current study aimed to investigate the antifungal properties of biosynthesized silver nanoparticles (AgNPs) made from R. stricta aqueous extract and its alkaline aqueous fraction. Fourier transform infrared spectroscopy (FTIR), UV-vis spectrophotometry, dynamic light scattering (DLS), and transmitted electron microscopy (TEM) were used to characterize AgNPs. The produced extracts and AgNPs were tested for their antifungal efficacy against four Fusarium spp. All of the characterization experiments proved the biosynthesis of targeted AgNPs. FTIR showed a wide distribution of hydroxyl, amino, carboxyl, and alkyl functional groups among all preparations. The DLS results showed that the produced Aq-AgNPs and the Alk-AgNPs had an average size of 95.9 nm and 54.04 nm, respectively. On the other hand, TEM results showed that the Aq-AgNPs and Alk-AgNPs had average diameters ranging from 21 to 90 nm and 7.25 to 25.32 nm. Both AgNPs absorbed UV light on average at 405 nm and 415 nm, respectively. Regarding the fungicidal activity, the highest doses of Aq-extract and Aq-AgNPs inhibited the mycelial growth of F. incarnatum (19.8%, 87.5%), F. solani (28.1%, 72.3%), F. proliferatum (37.5%, 75%), and F. verticillioides (27.1%, 62.5%), respectively (p < 0.001). Interestingly, the Alk-fraction had stronger inhibition than the biosynthesized AgNPs, which resulted in complete inhibition at the doses of 10% and 20% (p < 0.001). Furthermore, microscopic analysis demonstrated that both AgNPs caused obvious morphological alterations in the treated organisms when compared to the control. In conclusion, R. stricta's Aq-extract, alkaline fraction, and their biosynthesized AgNPs show substantial antifungal efficacy against several Fusarium spp. It is the first study to highlight the prospective biological activities of R. stricta Aq-extract and its alkaline fraction against F. incarnatum, F. proliferatum, and F. verticillioides. In addition, it is the first opportunity to deeply investigate the ultrastructural changes induced in the Fusarium species treated with R. stricta crude Aq-extract and its biosynthesized AgNPs. More studies are required to investigate their biological effect against other Fusarium or fungal species. [ABSTRACT FROM AUTHOR]

Background: Denture stomatitis (DS) is a chronic mucosa inflammation that supports removable dentures. Candida albicans is the most critical factor in the pathogenesis of DS. Systemic antifungal drugs such as nystatin are effective in people with acute candidiasis. Yet, in cases of predisposing factors such as a denture, nystatin cannot completely control the infection, andrecurrences are common. Objectives: In this study, the resistance and sensitivity of oral C. albicans species to nystatin were evaluated, and the effect of silver nanoparticles (AgNPs) was investigated on the nystatin-resistant specimens. Methods: This in vitro study was performed on 20 C. albicans specimens isolated from patients with denture stomatitis. After confirmation of C. albicans and in vitro biofilm preparation, nystatin was applied to the biofilm. The results were recorded as minimum growth inhibitory concentration (MIC) using Clinical & Laboratory Standards Institute (CLSI) standard protocol, and the specimens with MIC of more than 1 g/mL were categorized as resistant. Then, biofilms were re-formed for nystatin-resistant specimens exposed to AgNPs, and MIC results were reported. Results: This study revealed that 8 C. albicans specimens (40%) represented a MIC of more than 1 g/mL when exposed to nystatin. The results of AgNPs exposure to this group showed significantly higher efficiency of AgNPs than nystatin (P < 0.05). AgNPs can reduce the MIC of 6 nystatin-resistant specimens (75% of all resistant specimens). Conclusions: Both nystatin and AgNPs are effective against Candida biofilms formed on denture surfaces. However, AgNPs seem more effective in the case of resistant species. [ABSTRACT FROM AUTHOR]

Scutellaria multicaulis is a medicinal plant indigenous to Iran, Afghanistan, and Pakistan. It has been widely used as a prominent herb in traditional medicine for thousands of years. This plant is reported to contain baicalein, wogonin, and chrysin flavonoids, which are a significant group of chemical ingredients which can cure different diseases, such as breast cancer. S. multicaulis leaf extract was used for the bioreduction of silver nanoparticles (SmL-Ag-NPs), and their phytochemical contents and antioxidant, antibacterial, anti-proliferative, and apoptotic activity were evaluated. Optimal physicochemical properties of SmL-Ag-NPs were obtained by mixing 5% of leaf extract and 2 mM of aqueous AgNO3 solution and confirmed by characterization studies including UV–visible spectrophotometry, Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS), zeta potential, Thermogravimetric analysis (TGA), Surface-enhanced Raman spectroscopy (SERS), X-ray crystallography (XRD), and Fourier transform infrared (FTIR) Spectroscopy. SmL-Ag-NPs exhibited a higher content of total phenol and total flavonoid and potential antioxidant activity. SmL-Ag-NPs also demonstrated dose-dependent cytotoxicity against MDA-MB231 cell multiplication with an IC50 value of 37.62 μg/mL through inducing cell apoptosis. Results show that SmL-Ag-NPs is effective at inhibiting the proliferation of MDA-MB231 cells compared to tamoxifen. This demonstrates that SmL-Ag-NPs could be a bio-friendly and safe strategy to develop new cancer therapies with a reduction in the adverse effects of chemotherapy in the near future. [ABSTRACT FROM AUTHOR]

Introduction: There are numerous dressings used to treat pressure ulcers (PUs), depending on their advantages to achieve optimum patient outcomes. This study aimed to compare hydrocolloid dressings and silver nanoparticles in treating PUs among patients with spinal cord injury (SCI). Methods: This randomized clinical trial was conducted on 70 patients with SCI in Iran. Participants were randomly divided into two equal groups (n = 35) receiving silver nanoparticle dressing and hydrocolloid dressing, respectively. The groups were evaluated in four assessment periods using the Bates-Jensen Wound Assessment Tool (BWAT). Data analysis was performed using SPSS software version 13, repeated measures ANOVA, non-parametric tests, and chisquare. Results: Chi-square test was used to investigate the difference between the scores before the intervention, the results of which were not statistically significant. In repetitive measurements, the results of the analysis of variance showed that the average assessment score in both groups decreased and both dressings were effective in the treatment process. Although PU improvement status in the group that received silver nanoparticles was better, between-group analysis of variance did not show any statistically significant difference between the two groups. Conclusion: Our results indicated that silver nanoparticles and hydrocolloid dressings can be used interchangeably in the treatment of PUs. [ABSTRACT FROM AUTHOR]

Objective: The use of nanotechnologies is important to reduce environmental health problems in Iran, so the present study was conducted to determine the effectiveness of nanotechnologies in environmental health. This is a cross-sectional descriptive study for 11-year periods (2008–2018) on all articles published in three specialized journals of environmental health with emphasis on the use of nanotechnologies in various fields of environmental health (water, air, sewage, waste, food, radiation, etc). Results: In this study, 774 articles related to 114 issues of 3 specialized environmental health journals were reviewed. A review of 774 articles showed that 80 articles (10.3%) were published in the field of nanotechnologies. Out of 80 articles published in the field of nanotechnology, 66 articles (82.5%) were published on the subject of water, 9 articles (11.3%) on wastewater and 5 articles (6.2%) on air pollution. Subject review of articles showed that articles using carbon nanotubes to remove natural organic pollutants, surfactants, hydroxybenzenes, phenol, dimethyl phthalates, use of titanium dioxide nanoparticles, iron-magnesium nanoparticles for wastewater treatment, Silver nanoparticles were used to remove air pollution. The results showed that published articles on nanotechnology in the field of environmental health were few. [ABSTRACT FROM AUTHOR]

Over the recent years, banana cultivation has increased in the South-Eastern provinces of Iran. Management of Fusarium diseases in banana poses considerable yield loss as the application of chemical and biological treatments remains challenging. At the present research, about 10 Fusarium isolates causing dry rot on banana fruits were isolated and based on the pathogenicity test, isolate MSN-7 was considered as the most pathogenic isolate. Isolate MSN-7 was identified by using the ITS (ITS1 and ITS4) genomic region. BLAST results showed that it had the highest similarity (99%) with Fusarium chalmydosporum (MN533778.1). The objective of our research was to examine different concentrations of Silver nanoparticles (SNPs) biosynthesized by Paulownia fortunei L.) Fruit Exudates as a novel antifungal agent for reduce of pathogencity of Fusarium dry rot of banana. The synthesis of SNPs was conducted utilizing Paulownia fruit extracts as an environmentally friendly biosource. The exudates derived from Paulownia fruit demonstrated the capability to generate nanoparticles with an average size of 46 nm. Analysis conducted using a transmission electron microscope (TEM) revealed that these nanoparticles possess a polyhedral structure. Furthermore, when applied at concentrations of 10, 20, 40, and 80 μg/ml, these biosynthetic nanoparticles exhibited the ability to inhibit the growth of Fusarium fungus mycelia, as well as induced the destruction of the fungal hyphae. • Fusarium isolates causing dry rot on banana fruits were isolated. • Isolate MSN-7 was considered as the most pathogenic isolate. • Silver nanoparticles biosynthesized by Paulownia fortunei L. Fruit exudates. • Fusarium mycelia, as well as induced the destruction of the fungal hyphae. [ABSTRACT FROM AUTHOR]

The development of eco-friendly and nontoxic processes for the synthesis of nanoparticles is one of the most important discussed issues in nanotechnology science. This study reports the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of leaf, stem, and root of Avicennia marina, the native and dominant mangrove plant in southern Iran. Among the different plant parts, the extract of leaves yielded the maximum synthesis of AgNPs. Synthesized AgNPs were investigated using UV-visible spectrophotometry, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) spectroscopy. Absorption spectrum in 420 nm confirmed the synthesis of AgNPs. TEM images revealed that the synthesized AgNPs had the same spherical morphology with a size range between 0 and 75 nm. The distribution size histogram indicated that the most frequent particles were in the range of 10-15 nm and the mean size of nanoparticles was 17.30 nm. The results of SEM image showed nanoparticles with a size range between 15 and 43 nm. XRD pattern indicated the crystalline nature of synthesized nanoparticles. EDS results confirmed the presence of elements like silver, carbon, chlorine, nitrogen, and oxygen in the nanoparticles produced from leaf extract. Silver had the maximum percentage of formation, 51.6%. FTIR indicated the presence of different functional groups such as amines, alcohol, alkanes, phenol, alkyl halides, and aromatic loops in the synthesis process. Green biosynthesis of AgNPs using aqueous extract of native A. marina appears rapid, reliable, nontoxic, and eco-friendly. [ABSTRACT FROM AUTHOR]

Background and Aims: The use of microorganisms in the synthesis of metal nanoparticles is known as an eco-friendly method. Moreover, because of the ability of microorganisms to synthesize nanoparticles of various sizes, shapes and morphologies, this method has gained extreme attentions in recent years. The aim of this study was, therefore, to investigate the antimicrobial effects of silver nanoparticles synthesized by bacteria isolated from agricultural soils of Kerman, Iran. Materials and Methods: This study was carried out in 2014. Silver nanoparticles were characterized by SEM, EDS and XRD analyzes. The antimicrobial effects of silver nanoparticles were also assessed against some pathogenic bacteria. Results: Of the 40 silver nanoparticle producing bacteria, the strains that were able to produce silver nanoparticles with high antimicrobial activity yielded under different environmental conditions, were selected. The results of scanning electron microscopy (SEM) confirmed the presence of silver nanoparticles with a spherical shape. EDS analysis showed that silver content of the particles was about 60 wt %. Sequence alignment and phylogenetic tree results showed that M9 and B7 strains are closely related to Bacillus cereus and Pseudomonas argentinensis, respectively, with 99% homology. Conclusions: The results showed that the M9 and B7 strains can synthesize silver nanoparticles with high antimicrobial effects under different environmental conditions. [ABSTRACT FROM AUTHOR]

This study reports screening of 102 Iranian medicinal plant species belonging to 49 families for the biosynthesis of colloidal silver nanoparticles (AgNPs). Among tested plants, 37 species in 19 plant families are new bio-resources in this regard. Water extracts of macerated plant parts are used in this survey. Six of the bioactive plants are selected for further analysis. They produced amorphous spherical 40-70 nm AgNPs. Biosynthesised colloidal AgNPs are characterised by UV-visible spectroscopy, transmission electron microscopy and scanning electron microscopy. Families of Lamiaceae (8 out of 12), Leguminosae (7 out of 9), Liliaceae (4 out of 7) contained most bio active species. No correlation noticed between bioactivity and pH of plant water-extracts. The simple procedure used in this study may form a platform for mass production of environmentally safe and eco-friendly green production of these multipurpose AgNPs in future; however, optimisation protocols need to be well documented. [ABSTRACT FROM AUTHOR]

Heracleum persicum , commonly called Persian hogweed, is widely used as a spice in Iran. H. persicum comprises many natural compounds which are used in the treatment of multiple disorders. H. persicum stem extract was used for green synthesis of silver nanoparticles (Hp-AgNPs) and their phytochemical contents and antioxidant, and anti-proliferative activities were evaluated against human breast cancer cells (MDA-MB231) in this study. We found an optimal reaction medium consists of 5% of stem extract and 2 mM of aqueous AgNO 3 solution. Characterization studies including UV–visible spectrophotometry at a range of 300-700 nm, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Xray (EDX), X-ray Diffraction (XRD), Dynamic Light Scattering (DLS), Zeta potential, Fourier Transform Infrared (FTIR) and Surface-Enhanced Raman Spectroscopy (SERS) confirmed the optimal shape, size and stability of biosynthesized Hp-AgNPs. Results revealed that Hp-AgNPs contains higher TPC (Total Phenolic Content) and TFC (Total Flavonoid Content) and indicate a high level of antioxidant activity. The anticancer activity of Hp-AgNPs validated with inhibitory activity on growth of MDA-MB-231 cells. Results of Hp-AgNPs-treated MDA-MB-231 cells indicated an IC 50 value of 63.29 μg/mL at 48h. Results of this study provide a simple, rapid, non-toxic and eco-friendly protocol for biosynthesis of Hp-AgNPs, which could be used as an alternative approach for safe and simple synthesis of silver nanoparticles for biomedical applications. [ABSTRACT FROM AUTHOR]

Objective: Nanosilver has numerous applications in medicine due to its potent antibacterial activity. However, data regarding the bio-safety of its effective concentrations is scarce. This study aims to assess the toxicity of silver nanoparticles on human gingival epithelial cells under in-vitro conditions. Methods: This in-vitro study evaluated the toxic effects of filtered and unfiltered nanosilver solution on human gingival epithelial cells obtained from the Pasteur Institute of Iran using the methylthiazol tetrazolium bromide (MTT) assay(mitochondrial function)and membrane leakage of lactate dehydrogenase (LDH) at 24, 48 and 72h time points. The concentrations of silver nanoparticle solution used were 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20 and 50μg/ml. Results: The MTT assay showed that nanosilver solution at high concentrations (20 and 50μg/ml) significantly decreased the viability of cells at all time points. The lower non-fatal concentrations at 24 and 48h were capable of causing cell death or significantly inhibit cell growth at 72h. The LDH assay demonstrated that death of epithelial cells only occurs at high concentrations of nanosilver (20 and 50μg) and no significant toxicity was seen at lower concentrations. Conclusion: Based on the results, silver nanoparticles have toxic effects on human gingival epithelial cells and this effect is time and dose-dependent. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Acinetobacter baumannii (CRAB) remains as a serious cause of infectious diseases and septic mortality in hospitalized patients worldwide. This study was conducted to evaluate the antimicrobial effect of imipenem conjugated silver nanoparticles (AgNPs) on resistant isolated A. baumannii from nosocomial infections.The antimicrobial susceptibility test of 100 A. baumannii clinical isolates against different antibiotics was performed. PCR was used to confirm bacterial resistance and to identify different genes encoding Ambler class β-lactamases. The chemically synthesized AgNPs were characterized using UV-vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared (FTIR). The stability, drug release kinetic, and cytotoxicity (MTT assay) of AgNPs were also investigated. The imipenem were conjugated with AgNPs, and conjugants were characterized as discussed above. Minimum inhibitory concentration (MIC) of the AgNPs and conjugants were tested against A. baumannii isolates and compared with imipenem alone.The results revealed that among all isolated A. baumannii, 76% showed resistant to imipenem (MIC ≥ 64 μg/mL to ≥ 256 μg/mL). The bla OXA-23 , bla PER , bla OXA-40 , and bla IMP genes were the most prevalent genes. UV-vis spectroscopy, XRD, TEM, and FTIR analysis confirmed synthesis of AgNPs (average size of 10-40 nm) and conjugation with imipenem. The release of imipenem from AgNPs can be defined as Fickian diffusion model. The MIC values of AgNPs conjugated with imipenem against resistant A. baumannii were decreased in a dose dependent manner and were based on existence of resistant genes. The AgNPs also showed low cytotoxic effects.The results suggest that imipenem-AgNPs has a strong potency as a powerful antibacterial agent against multi-resistant A. baumannii.

Biosynthesis of carnosic acid (CA), one of the most industrially valuable medicinal compounds present in rosemary (Rosmarinus officinalis L.) leaves, is affected by various plant stressors. In this study, effects of silver nanoparticle (AgNP) treatment on the secondary metabolism and CA production of rosemary plants were investigated. AgNP of 0, 25, 50, 100, and 200 ppm were utilized on hydroponically grown plants using foliar spray. Efficient absorbance and translocation of AgNPs to the plant roots were confirmed by XRF (X-ray fluorescence) analysis. The fluctuations of important antioxidant compounds such as CA content, phenolics, flavonoids, and acid ascorbic were analyzed and their correlations evaluated. Results revealed that application of 200 ppm AgNPs for 12 days increased CA level more than 11%, as compared to the control plants. Furthermore, significant positive correlations were observed between total flavonoids and CA content under AgNP treatment, suggesting that AgNP acted as an elicitor and triggered the enhancement of CA accumulation effectively. These data suggest that concentration-dependent AgNP may be used to boost antioxidant activity and phytochemical contents of other medicinal plants.

An electrochemical biosensor was developed for Hg(2+) determination based on DNA hybridization. In the presence of Hg(2+), the target and probe DNAs with thymine-thymine (T-T) mismatches could hybridize by forming T-Hg(2+)-T complex. This induced DNA hybridization led to the decrease in reduction peak currents of ethyl green (EG) as electroactive label, which could be used for determination of Hg(2+). The difference in the value of the peak currents of EG before and after DNA hybridization (ΔI) was linear with the concentration of Hg(2+) in the range of 9.0 × 10(-11)-1.0 × 10(-9) M. The detection limit was 3.08 × 10(-11) M., (Copyright © 2015 Elsevier Inc. All rights reserved.)