scholarly journals Titanium Dioxide Nanoparticles are Toxic for the Freshwater Mussel Unio ravoisieri: Evidence from a Multimarker Approach

Diversity ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 679
Author(s):  
Hanen Smii ◽  
Abdelhafidh Khazri ◽  
Manel Ben Ben Ali ◽  
Amine Mezni ◽  
Amor Hedfi ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Cholinergic System ◽  
Metallic Nanoparticles ◽  
Titanium Dioxide Nanoparticles ◽  
Freshwater Mussel ◽  
Acetylcholinesterase Activity ◽  
Sentinel Species ◽  
Hydrogen Peroxide Production ◽  
Biochemical Analyses ◽  
Digestive Glands

The current work investigated the ecotoxicological effects induced by Titanium Dioxide (TiO2) nanoparticles (NPs), used at three different concentrations (C1 = 10 μg·L−1, C2 = 100 μg·L−1 and C3 = 1000 μg·L−1) in a laboratory experiment, on the freshwater mussel Unio ravoisieri. Biochemical analyses of gills and digestive glands revealed a stress-related disruption of the antioxidant system. The catalase activity and the rates of malonedialdehyde and hydrogen peroxide production were significantly higher in both organs following the exposure to TiO2 NPs and was concentration-dependent. In addition, based on the observed changes in acetylcholinesterase activity, it can be concluded that the disturbance threshold for the cholinergic system was less than 1 mg·L−1 of TiO2. Overall, the results suggest that the mussel Unio ravoisieri could be used as a sentinel species in monitoring surveys assessing the environmental impact of metallic nanoparticles in freshwater systems.

scholarly journals Titanium Dioxide Nanoparticles – Prospects and Applications in Medicine

2020 ◽  
Author(s):  
Daniel Ziental ◽  
Beata Czarczynska-Goslinska ◽  
Dariusz T. Mlynarczyk ◽  
Arleta Glowacka-Sobotta ◽  
Beata Stanisz ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Metallic Nanoparticles ◽  
Malignant Tumors ◽  
Uv Light ◽  
Titanium Dioxide Nanoparticles ◽  
Aqueous Media ◽  
Resistant Bacteria ◽  
Antibiotic Resistant ◽  
Tio2 Nps ◽  
Wide Range

Metallic nanoparticles (NPs), among polymeric NPs, liposomes, micelles, quantum dots, dendrimers, or fullerenes, are becoming more and more important due to their potential use in the novel medical therapies. Titanium dioxide (titanium(IV) oxide, titania, TiO2) is an inorganic compound that owes its recent rise in scientific interest to photoactivity. After the illumination in aqueous media with UV light, TiO2 produces an array of reactive oxygen species (ROS). The capability to produce ROS and thus induce cell death has found application in the photodynamic therapy (PDT) for the treatment of a wide range of maladies, from psoriasis to cancer. Titanium dioxide NPs were studied as photosensitizing agents in the treatment of malignant tumors as well as in photodynamic inactivation of antibiotic-resistant bacteria. Both TiO2 NPs themselves, as well as their composites with other molecules, can be successfully used as photosensitizers in PDT. Moreover, various organic compounds can be grafted on TiO2 NPs, leading to hybrid materials. These nanostructures can reveal increased light absorption allowing their further use in targeted therapy in medicine. In order to improve efficient anticancer therapy, many approaches utilizing titanium dioxide were tested. The most significant studies are discussed in this review.

scholarly journals Salt Stress Mitigation via the Foliar Application of Chitosan-Functionalized Selenium and Anatase Titanium Dioxide Nanoparticles in Stevia (Stevia rebaudiana Bertoni)

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4090
Author(s):  
Morteza Sheikhalipour ◽  
Behrooz Esmaielpour ◽  
Gholamreza Gohari ◽  
Maryam Haghighi ◽  
Hessam Jafari ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Salt Stress ◽  
Titanium Dioxide Nanoparticles ◽  
Chitosan Nanoparticles ◽  
Stevia Rebaudiana ◽  
High Salt ◽  
Steviol Glycosides ◽  
Rebaudioside A ◽  
Tio2 Nps ◽  
Stevia Rebaudiana Bertoni

High salt levels are one of the significant and major limiting factors on crop yield and productivity. Out of the available attempts made against high salt levels, engineered nanoparticles (NPs) have been widely employed and considered as effective strategies in this regard. Of these NPs, titanium dioxide nanoparticles (TiO2 NPs) and selenium functionalized using chitosan nanoparticles (Cs–Se NPs) were applied for a quite number of plants, but their potential roles for alleviating the adverse effects of salinity on stevia remains unclear. Stevia (Stevia rebaudiana Bertoni) is one of the reputed medicinal plants due to their diterpenoid steviol glycosides (stevioside and rebaudioside A). For this reason, the current study was designed to investigate the potential of TiO2 NPs (0, 100 and 200 mg L−1) and Cs–Se NPs (0, 10 and 20 mg L−1) to alleviate salt stress (0, 50 and 100 mM NaCl) in stevia. The findings of the study revealed that salinity decreased the growth and photosynthetic traits but resulted in substantial cell damage through increasing H2O2 and MDA content, as well as electrolyte leakage (EL). However, the application of TiO2 NPs (100 mg L−1) and Cs–Se NPs (20 mg L−1) increased the growth, photosynthetic performance and activity of antioxidant enzymes, and decreased the contents of H2O2, MDA and EL under the saline conditions. In addition to the enhanced growth and physiological performance of the plant, the essential oil content was also increased with the treatments of TiO2 (100 mg L−1) and Cs–Se NPs (20 mg L−1). In addition, the tested NPs treatments increased the concentration of stevioside (in the non-saline condition and under salinity stress) and rebaudioside A (under the salinity conditions) in stevia plants. Overall, the current findings suggest that especially 100 mg L−1 TiO2 NPs and 20 mg L−1 Cs–Se could be considered as promising agents in combating high levels of salinity in the case of stevia.

scholarly journals Effect of Titanium Dioxide Nanoparticles on the Expression of Efflux Pump and Quorum-Sensing Genes in MDR Pseudomonas aeruginosa Isolates

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 625
Author(s):  
Fatma Y. Ahmed ◽  
Usama Farghaly Aly ◽  
Rehab Mahmoud Abd El-Baky ◽  
Nancy G. F. M. Waly
Keyword(s):  
Titanium Dioxide ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Efflux Pumps ◽  
Antibiofilm Activity ◽  
The Impact

Most of the infections caused by multi-drug resistant (MDR) P. aeruginosa strains are extremely difficult to be treated with conventional antibiotics. Biofilm formation and efflux pumps are recognized as the major antibiotic resistance mechanisms in MDR P. aeruginosa. Biofilm formation by P. aeruginosa depends mainly on the cell-to-cell communication quorum-sensing (QS) systems. Titanium dioxide nanoparticles (TDN) have been used as antimicrobial agents against several microorganisms but have not been reported as an anti-QS agent. This study aims to evaluate the impact of titanium dioxide nanoparticles (TDN) on QS and efflux pump genes expression in MDR P. aeruginosa isolates. The antimicrobial susceptibility of 25 P. aeruginosa isolates were performed by Kirby–Bauer disc diffusion. Titanium dioxide nanoparticles (TDN) were prepared by the sol gel method and characterized by different techniques (DLS, HR-TEM, XRD, and FTIR). The expression of efflux pumps in the MDR isolates was detected by the determination of MICs of different antibiotics in the presence and absence of carbonyl cyanide m-chlorophenylhydrazone (CCCP). Biofilm formation and the antibiofilm activity of TDN were determined using the tissue culture plate method. The effects of TDN on the expression of QS genes and efflux pump genes were tested using real-time polymerase chain reaction (RT-PCR). The average size of the TDNs was 64.77 nm. It was found that TDN showed a significant reduction in biofilm formation (96%) and represented superior antibacterial activity against P. aeruginosa strains in comparison to titanium dioxide powder. In addition, the use of TDN alone or in combination with antibiotics resulted in significant downregulation of the efflux pump genes (MexY, MexB, MexA) and QS-regulated genes (lasR, lasI, rhll, rhlR, pqsA, pqsR) in comparison to the untreated isolate. TDN can increase the therapeutic efficacy of traditional antibiotics by affecting efflux pump expression and quorum-sensing genes controlling biofilm production.

Impact of titanium dioxide nanoparticles on intestinal community in the 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced acute colitis mice and the intervention effect of vitamin E

Nanoscale ◽  
2020 ◽  
Author(s):  
Yanjun Gao ◽  
Tingyu Li ◽  
Shuming Duan ◽  
Lizhi Lv ◽  
Yuan Li ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Titanium Dioxide ◽  
Vitamin E ◽  
Titanium Dioxide Nanoparticles ◽  
Trinitrobenzenesulfonic Acid ◽  
Acute Colitis ◽  
Intervention Effect ◽  
Tio2 Nps

Titanium dioxide nanoparticles (TiO2-NPs) is widely applicated as additives in foods for its excellent whitening and brightening capability. Although the toxicity and antibacterial activity of TiO2-NPs has been extensively studied,...

scholarly journals Blackening of titanium dioxide nanoparticles by atomic hydrogen and the effect of coexistence of water on the blackening

RSC Advances ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 4270-4275
Author(s):  
Masahide Fujimoto ◽  
Masuaki Matsumoto ◽  
Naoki Nagatsuka ◽  
Katsuyuki Fukutani
Keyword(s):  
Titanium Dioxide ◽  
Atomic Hydrogen ◽  
Titanium Dioxide Nanoparticles

A fast blackening process of titanium dioxide nanoparticles by exposing to atomic hydrogen was studied by estimating the color of the nanoparticles.

Sign in / Sign up

Export Citation Format

Share Document