Bioaccumulation, Subacute Toxicity, and Tissue Distribution of Engineered Titanium Dioxide Nanoparticles in Goldfish (Carassius auratus)

The increased use of nanosized materials is likely to result in the release of these particles into the environment. It is, however, unclear if these materials are harmful to aquatic animals. In this study, the sublethal effects of exposure of low and high concentrations of titanium dioxide nanoparticles (TiO2 NPs) on goldfish (Carassius auratus) were investigated. Accumulation of TiO2 NPs increased from 42.71 to 110.68 ppb in the intestine and from 4.10 to 9.86 ppb in the gills of the goldfish with increasing exposure dose from 10 to 100 mg/L TiO2 NPs. No significant accumulation in the muscle and brain of the fish was detected. Malondialdehyde as a biomarker of lipid oxidation was detected in the liver of the goldfish. Moreover, TiO2 NPs exposure inhibited growth of the goldfish. Although there was an increase (8.1%) in the body weights of the goldfish for the control group, in the low and high exposure groups 1.8% increase and 19.7% decrease were measured, respectively. The results of this study contribute to the current understanding of the potential ecotoxicological effects of nanoparticles and highlight the importance of characterization of NPs in understanding their behavior, uptake, and effects in aquatic systems and in fish

Study of Structure and Spectral Characteristics of the Zinc(II) and Copper(II) Complexes With 5,5-Dimethyl-2-(2-(3-nitrophenyl) hydrazono)cyclohexane-1,3-dione and Their Effects on Optical Properties and the Developing of the Energy Band Gap and Investigation of Antibacterial Activity

WOS: 000333743200011A new chelating ligand, 5,5-dimethyl-2-(2-(3-nitrophenyl)hydrazono)cyclohexane-1,3-dione (L), and four transition metal complexes were synthesized. The ligand and its complexes were characterized by IR, H-1 and C-13-NMR spectra, elemental analyses, magnetic susceptibility, mass spectra, UV-Vis. and thermogravimetry-differential thermal analysis (TGA-DTA). The metal complexes showed different geometric structures. Antibacterial tests of the ligand and complexes were also done. The Zn(II) complexes showed antibacterial activity against Staphylococcus aureus ATCC-25923 at middle level. The optical properties of the ligand and its complexes were extensively investigated by optical measurements. The average transmittance value of the ligand was the highest value, while the average transmittance value of the [CuL2(NO3)(2)]center dot 6H(2)O complex was the lowest value. The optical band gap of the ligand, [(Zn)(2)L(OH)(4)]center dot 2DMF, [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O, [CuL2(OAc)]center dot OAc center dot 3.5H(2)O and [CuL2(NO3)(2)]center dot 6H(2)O complexes were calculated and 3.121 eV, 2.180 eV, 1.551 eV, 2.489 eV and 1.556 eV values were found, respectively. The complexes decreased the optical band gap of the ligand. The optical band gap value of the [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O complex is the lowest value. The optical band gap value of the ligand is the highest value. The complexes decrease the angle of incidence of the ligand, while complexes increase the angle of refraction of the ligand. The electric susceptibility of the ligand decreases with its complexes

Synthesis and Characterization of Ni(II) and Cd(II) Complexes of 4-(4-Nitrophenylazo)-1H-pyrazole-3,5-diamine and 4-(4-Methylphenylazo)-1H-pyrazole-3,5-diamine

WOS: 000293193000100In this study, the diazotized p-nitroaniline and p-methylaniline were coupled with malononitrile. The ring closure reaction of the obtained products with hydrazine monohydrate yielded 4-(4-methylphenylazo)-1H-pyrazole-3,5-diamine (L-1) and 4-(4-nitrophenylazo)-1H-pyrazole-3,5-diamine (L-2). The structure of the ligands has been elucidated by spectroscopic analyses. Then, novel Ni(II) and Cd(II) complexes of the ligands have been synthesized and the structures of these complexes determined by elemental analysis, spectrometric and TGA/DTA methods, molar conductance and magnetic susceptibility measurements. All the complexes were monomeric and diamagnetic. From the elemental analyses and mass spectra data, the complexes were proposed to the formulae [Ni-2(L-1)(2)(OH)(2)]center dot 2Cl center dot 8.5H(2)O, [Cd-2(L-1)(2)(OH)(2)]center dot 2Cl center dot DMF center dot 3H(2)O, [Ni(L-2)(2)]center dot 2Cl center dot 2DMF center dot 7H(2)O and [Cd-2(L-2)(2)(OH)(2)(H2O)(4)]center dot 2Cl center dot 1.5H(2)O. For the Cd(L-2) complex octahedral geometry was proposed, but the Ni(L-1), Ni(L-2) and Cd(L-1) complexes show four coordinated structure. The Ni(L-1), Cd(L-1) and Cd(L-2) complexes were found to be dinuclear. On the other hand the Ni(L-2) complex was found to be mononuclear. All the complexes were found to be (1:2) electrolytes.Research Foundation of Gazi UniversityGazi University [BAP- 05/2006-50]The authors are grateful to Research Foundation of Gazi University (BAP- 05/2006-50) supporting this study

Investigation of spectroscopic, thermal, and biological properties of Fe-II, Co-II, Zn-II, and Ru-II complexes derived from azo dye ligand

In this study, the novel azo dye Fe-II , Co-II , Zn-II , and Ru-II complexes with an azo dye ligand (L: (E)-4-((4-methoxyphenyl)diazenyl)-3-methyl-1H-pyrazol-5-amine) were synthesized. The structures of the complexes were characterized by FT-IR, elemental analysis, UV-Vis, mass spectra (Fe-II and Co-II ), NMR spectra (only diamagnetic Zn-II and Ru-II ), thermogravimetric and differential thermal analysis (TA-DTA). All of the newly synthesized compounds were tested for their biochemical properties, including enzyme inhibitory and antioxidant activities. According to the in vitro ABTS, DPPH, CUPRAC, and FRAP antioxidant methods, the ligand and its metal complexes showed close antioxidant activities to the standards (BHA, BHT, ascorbic acid, and alpha-tocopherol). Enzyme inhibitions of the metal complexes were investigated against glutathione S-transferase (GST), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes. The best inhibition values (Ki) were observed for Ru(II) complex against GST (14.36 +/- 2.16 mu M), AChE (16.86 +/- 2.74 mu M), and BChE (14.12 +/- 2.04 mu M). (C) 2021 Elsevier B.V. All rights reserved

“ Temporal Changes in Concentrations of Some Trace Elements in Muscle Tissue of Crayfish, Astacus leptodactylus (Eschscholtz, 1823) from Keban Dam Lake”

Crayfish (Astacus leptodactylus Eschscholtz, 1823) is the native crayfish species in Turkey. It was exported regularly to Western Europe. In this study, bioaccumulation and temporal trends of some trace elements (arsenic: As, cadmium: Cd, copper: Cu, mercury: Hg, lead: Pb, and zinc: Zn) in edible abdomen muscle of crayfish from Keban Dam Lake (Elazığ, Turkey) were investigated for the 2006–2012 period. Sequence of metal concentration levels was Zn > Cu > Hg > Pb > Cd > As in muscle tissues. The highest concentration of Zn (21.69 mg kg−1) was detected in 2006, while the lowest (4.35 mg kg−1) in 2009. In general, it was found that the concentrations of trace elements investigated were lower than the maximum permissible limits of the food regulations of the Ministry of Food, Agriculture, and Livestock (MFAL), the Turkish Food Codex and Commission Regulation (EC). If the crayfish selected for the study are recognized as bioindicators of environmental pollution, then it is possible to conclude that the changes in studied trace elements concentrations in the Keban Dam Lake are being steady