scholarly journals The Alkaline Sulfide Reduction of Aromatic Nitro Compounds. XII. ESR Studies of the Alkaline Sulfide Reduction of the Aromatic Nitro Compound

1967 ◽  
Vol 40 (12) ◽  
pp. 2867-2871 ◽  
Author(s):  
Shizunobu Hashimoto ◽  
Junzo Sunamoto ◽  
Akira Aoki
1991 ◽  
Vol 69 (12) ◽  
pp. 1881-1885 ◽  
Author(s):  
E. Theodoridou ◽  
A. D. Jannakoudakis ◽  
P. D. Jannakoudakis ◽  
S. Antoniadou

The adsorption of several aromatic nitro compounds and the ion-exchange of heavy metal ions on electro-oxidized carbon fibres have been investigated using cyclic voltammetric and polarographic techniques. Electro-oxidation is performed by potentiostatic double pulse application. This procedure results in the generation of many functional —OH and —COOH groups with adsorptive and ion-exchanging properties.Multimolecular layers of adsorbed substances may be formed through a procedure of successive adsorption of the nitro-compound and electro-reduction to the corresponding amine, resulting in the attachment of considerable amounts of the nitro-compound to the carbon fibres.The ion-exchange capacity is estimated to be ca. 1 mequiv. g−1 and with slight deviations it follows the rank Ag, Cu, Cd, Pb, Hg. After the electro-reduction of the exchanged metal ions, the ion-exchange process can be repeated several times. This procedure is of importance for the removal of significant amounts of heavy and toxic metals from industrial waste waters. Key words: electro-oxidized carbon fibres, adsorption of aromatic nitro compounds, cation-exchange of heavy metals.


Mutagenesis ◽  
2021 ◽  
Author(s):  
Yuki Otsubo ◽  
Shoji Matsumura ◽  
Naohiro Ikeda ◽  
Osamu Morita

Abstract A precise understanding of differences in genomic mutations according to the mutagenic mechanisms detected in mutagenicity data is required to evaluate the carcinogenicity of environmental mutagens. Recently, we developed a highly accurate genome sequencing method, ‘Hawk-Seq™’, that enables the detection of mutagen-induced genome-wide mutations. However, its applicability to detect various mutagens and identify differences in mutational profiles is not well understood. Thus, we evaluated DNA samples from Salmonella typhimurium TA100 exposed to 11 mutagens including alkylating agents, aldehydes, an aromatic nitro compound, epoxides, aromatic amines, and polycyclic aromatic hydrocarbons (PAHs). We extensively analysed mutagen-induced mutational profiles and their association with the mechanisms of mutagens. Hawk-Seq™ sensitively detected mutations induced by all 11 mutagens, including one that increased the number of revertants by approximately two-fold in the Ames test. Although the sensitivity for less water-soluble mutagens was relatively low, we increased the sensitivity to obtain high-resolution spectra by modifying the exposure protocol. Moreover, two epoxides indicated similar 6-dimensional or 96-dimensional mutational patterns; likewise, three SN1 type alkylating agents indicated similar mutational patterns, suggesting that the mutational patterns are compound category-specific. Meanwhile, an SN2 type alkylating agent exhibited unique mutational patterns compared to those of the SN1 type alkylating agents. Although the mutational patterns induced by aldehydes, the aromatic nitro compound, aromatic amines, and PAHs did not differ substantially from each other, the maximum total base substitution frequencies (MTSFs) were similar among mutagens in the same structural groups. Furthermore, the MTSF was found to be associated with the carcinogenic potency of some direct-acting mutagens. These results indicate that our method can generate high-resolution mutational profiles to identify characteristic features of each mutagen. The detailed mutational data obtained by Hawk-Seq™ can provide useful information regarding mutagenic mechanisms and help identify its association with the carcinogenicity of mutagens without requiring carcinogenicity data.


Sign in / Sign up

Export Citation Format

Share Document