RESUMEN
Herein, single-walled carbon nanotubes (SWCNTs) were synthesized by the thermal chemical vapor deposition (CVD) method, and characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), Raman spectroscopy, dynamic light scattering (DLS), and thermo-gravimetric analysis (TGA). The results indicated that obtained nanotubes were SWCNTs with high crystallinity and their average diameter was 10.15 ± 3 nm. Allium cepa ana-telophase and comet assays on the root meristem were employed to evaluate the cytotoxic and genotoxic effects of SWCNTs by examining mitotic phases, mitotic index (MI), chromosomal aberrations (CAs), and DNA damage. A. cepa root tip cells were exposed to SWCNTs at concentrations of 12.5, 25, 50, and 100 µg/ml for 4 h. Distilled water and methyl methanesulfonate (MMS, 10 µg/ml) were used as the negative and positive control groups, respectively. It was observed that MIs decreased statistically significantly for all applied doses. Besides, CAs such as chromosome laggards, disturbed anaphase-telophase, stickiness and bridges and also DNA damage increased in the presence of SWCNTs in a concentration-dependent manner. In the molecular docking study, the SWCNT were found to be a strong DNA major groove binder showing an energetically very favorable binding free energy of -21.27 kcal/mol. Furthermore, the SWCNT interacted effectively with the nucleotides on both strands of DNA primarily via hydrophobic π and electrostatic interactions. As a result, cytotoxic and genotoxic effects of SWCNTs in A. cepa root meristematic cells which is a reliable system for assessment of nanoparticle toxicology were demonstrated in this study. RESEARCH HIGHLIGHTS: SWCNT synthesis with high crystallinity was achieved by the CVD method. Cytotoxic and genotoxic influences of SWCNTs were investigated. Allium and Comet tests were utilized. For all of the applied concentrations of SWCNTs, the MIs significantly decreased. SWCNTs were found genotoxic.
Asunto(s)
Nanotubos de Carbono , Cebollas , Aberraciones Cromosómicas , Daño del ADN , Meristema , Simulación del Acoplamiento Molecular , Nanotubos de Carbono/toxicidad , Cebollas/genética , Raíces de PlantasRESUMEN
The fungi are becoming the distinguished organisms utilized in the biological synthesis of metallic nanoparticles because of their metal bioaccumulation ability. Addressed herein, the extracellular synthesis of silver nanoparticles (AgNPs) was carried out by using the cell-free filtrate of Penicillium toxicarium KJ173540.1. P. toxicarium was locally isolated and identified using both classical and molecular methods according to ribosomal internal transcribed spacer area of 18S rDNA. The optimum conditions for the AgNPs synthesis were found as 0.25 mM AgNO3 concentrations with pH 12 values at 45°C after 64 hr incubation in dark. Biosynthesized AgNPs were characterized via microscopic and spectroscopic techniques such as transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectrophotometer, and ultraviolet-visible spectroscopy. Zetasizer measurements presented that the high negative potential value (-18.1 mV) and PDI (0.495) supported the excellent colloidal nature of AgNPs with long-range stability and high dispersity. AgNPs exhibited cyto-genotoxicity in Allium cepa root meristem cells by decreasing mitotic index and increasing chromosome aberrations in a dose-dependent manner. Then, 100 and 50% concentration of biosynthesized AgNPs showed antibacterial activity on Staphylococcus aureus and Bacillus subtilis. A decreasing biofilm formation of Pseudomonas aeruginosa 80.69, 48.32, and 28.41% was also observed at 100, 50, and 25% of mycosynthesized AgNP, respectively.
Asunto(s)
Nanopartículas del Metal , Penicillium , Antibacterianos/farmacología , Biopelículas , Nanopartículas del Metal/toxicidad , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plata/toxicidad , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Tungsten oxide nanoparticles or nanopowder (WO3NPs) is commonly used in various industries and also in biomedical applications such as additives, pigments, and biomedical sensors. Non-judicious excessive use of these nanoparticles (NPs) could be a serious human health concern. Therefore, the current study aimed to explore the cytotoxic and genotoxic assessment of WO3NPs through Allium cepa anaphase-telophase and comet assays. Nanoparticles were characterized through the scanning and transmission electron microscopy (TEM), zetasizer, and energy-dispersive X-ray spectroscopy. The mean size and the average diameter of WO3NPs were determined as 21.57 ± 2.48 nm and 349.42 ± 80.65 nm using TEM and a Zetasizer measurement system, respectively. Five concentrations (12.5 mg/L, 25 mg/L, 50 mg/L, 75 mg/L, and 100 mg/L) of WO3NPs were employed on the Allium cepa (A. cepa) roots for 4 h. Significant (p ≤ 0.05) decrease in mitotic index (MI) was shown by WO3NPs at all concentrations. The increase of chromosomal aberrations (CAs) was also observed in a concentration-dependent manner due to the WO3NPs exposure. There was a significant increase (p ≤ 0.05) in DNA damage at all concentrations of WO3NPs on the A. cepa cells. It was concluded that WO3NPs had cytotoxic and genotoxic effects on A. cepa meristematic cells. Moreover, further cytogenetic effects of WO3NPs should be investigated at the molecular level to assess its safety margin.
Asunto(s)
Nanopartículas , Cebollas/genética , Óxidos/toxicidad , Tungsteno/toxicidad , Aberraciones Cromosómicas , Ensayo Cometa , Daño del ADN , Nanopartículas/toxicidad , Cebollas/efectos de los fármacos , Raíces de Plantas , TelofaseRESUMEN
In this study pillar[5]arene (P5) and a quinoline-functionalized pillar[5]arene (P5-6Q) which is used for detecting radioactive element, gas adsorption and toxic ions were synthesized. These materials were characterized by Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared (FTIR), elemental analysis, melting point, Mass Spectroscopy, Scanning Electron Microscopy (SEM) and Zeta Potential. The cytotoxic and genotoxic potential of P5 and P5-6Q at distinct concentrations of 12.5, 25, 50, and 100 µg/mL were also investigated by Allium ana-telophase and comet assays on Allium cepa roots and Drosophila melanogaster haemocytes. P5 and P5-6Q showed dose dependent cytotoxic effect by decreasing mitotic index (MI) and genotoxic effect by increasing chromosomal aberrations (CAs such as disturbed anaphase-telophase, polyploidy, stickiness, chromosome laggards and bridges) and DNA damage at the exposed concentrations. These changes in P5-6Q were lower than P5. Further research is necessary to clarify the cytotoxic and genotoxic action mechanisms of P5 and P5-6Q at molecular levels.
Asunto(s)
Calixarenos/toxicidad , Daño del ADN , Drosophila melanogaster/efectos de los fármacos , Cebollas/efectos de los fármacos , Anafase/efectos de los fármacos , Animales , Calixarenos/química , Aberraciones Cromosómicas , Ensayo Cometa , Citotoxinas/química , Citotoxinas/toxicidad , Drosophila melanogaster/genética , Hemocitos/efectos de los fármacos , Índice Mitótico , Cebollas/genética , Raíces de Plantas/efectos de los fármacos , Quinolinas/síntesis química , Quinolinas/química , Quinolinas/toxicidad , Telofase/efectos de los fármacosRESUMEN
Silicon nanoparticles gained a great interest due to its use in biomedical research. It is considered as safe and has been used in nanomedicine. But literature still states its toxicity depending upon the size and dose of silicon nanoparticles. So, current study was aimed to evaluate the cytotoxicity and genotoxicity of silicon dioxide nanoparticles (SiO2NPs) by Allium anaphase-telophase and Comet tests. Characterization of SiO2NPs showed the particle size as 16.12 ± 3.07 nm. The mean diameter of SiO2NPs was having range of 404.66 ± 93.39 nm in solution. Highest total anomalies (18.80 ± 0.45) were observed at 100 µg/mL, whereas least (11.2 ± 0.84) were observed by the 12.5 µg/mL concentration. There was concentration-response association in increased CAs and DNA damage. The highest concentration (100 µg/mL) of SiO2NPs induced the significant DNA damage (149.67 ± 1.15), whereas the least was observed by the negative control (2.67 ± 0.58). The current study revealed the cytotoxic and genotoxic effects of SiO2NPs on the root meristem cells of A. cepa.
Asunto(s)
Nanopartículas/toxicidad , Cebollas/efectos de los fármacos , Dióxido de Silicio/toxicidad , Allium , Ensayo Cometa/métodos , Daño del ADN , Meristema/citología , Meristema/efectos de los fármacos , Meristema/genética , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Pruebas de Mutagenicidad/métodos , Cebollas/citología , Cebollas/genética , Tamaño de la Partícula , Raíces de Plantas/citología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genéticaRESUMEN
Cerium oxide (CeO2) is extensively used in a range of applications like in television tubes, glass/ceramic polishing agent, fuel cells, solar cells, gas sensor andultraviolet absorbents. In current study, Allium ana-telophase and comet assays were employed to evaluate the cytotoxic and genotoxic effects of CeO2 microparticles (CMPs, <5⯵m, bulk) and CeO2 nanoparticles (CNPs, <â¯25â¯nm) on the root meristem cells of Allium cepa by using mitotic phases, mitotic index (MI), chromosomal aberrations (CAs), and DNA damage. A cepa roots were treated with the CMPs and CNPs at four different concentrations (12.5, 25, 50, and 100â¯ppm) for 4â¯h. Methyl methane sulphonate (MMS,10â¯ppm) and distilled water were used as positive and negative control groups, respectively. All the applied doses statistically decreased MIs. MI values of CMPs were found higher than CNPs. CMPs and CNPs significantly increased CAs such as chromosome laggards, disturbed anaphase-telophase, stickiness and bridges and also DNA damage. Characterization of CMPs and CNPs showed the particle size as 4.24⯱â¯0.7⯵m and 20.28⯱â¯2.33â¯nm, respectively. The average diameter of CMPs and CNPs in solution were in the range of 372.75⯱â¯70.23â¯nm and 167.74⯱â¯38.7â¯nm, respectively. These results demonstrated that CMPs and CNPs had cytotoxic and genotoxic effects in A. cepa root meristematic cells.