Oxidative stress in Arthrospira platensis by two organophosphate pesticides.

Although it is known that organophosphate insecticides are harmfull to aquatic ecosystems, oxidative damages caused by Dimethoate and Chlorpyrifos are not studied on Arthrospira platensis Gomont. In this study, various Chlorpyrifos (0-150 µg mL-1) and Dimethoate (0-250 µg mL-1) concentrations were added to the culture medium in laboratory to evaulate growth rate, chlorophyll-a content and antioxidant parameters of A. platensis. Optical Density (OD560) and chlorophyll-a decreased compared to the control for seven days in both pesticide applications. Superoxide dismutase (SOD) activity increased at 50 µg mL-1 Chlorpyrifos concentration but it decreased at all concentrations. Although Ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased with Chlorpyrifos application, they did not change with Dimethoate application. Malondialdehyde (MDA) amount decreased at 150 µg mL-1 Chlorpyrifos concentration but it increased in Dimethoate application. The H2O2 content were increased in both applications. Proline decreased in 50 and 75 µg mL-1 Chlorpyrifos concentrations and increased at 150 µg mL-1 concentration, while it increased at 25 µg mL-1 Dimethoate concentration. The results were tested at 0.05 significance level. These pesticides inhibit A. platensis growth and chlorophyll-a production and cause oxidative stress. The excessive use may affect the phytoplankton and have negative consequences in the aquatic ecosystem.

Algaecidal and oxidative effects of metal-free phthalocyanine beta tetra-substituted with sodium 2-mercaptoethanesulfonate.

In this study, a water-soluble metal-free phthalocyanine (SPC) containing sodium 2-mercaptoethanesulfonate substituents at the peripheral positions was used to investigate the algaecidal properties and oxidative effects on the growth of two microalgal species, Arthrospira platensis and Chlorella vulgaris. Although OD at 560 nm and chlorophyll-a content were decreased in Arthrospira platensis during 7 days depending on dose and time, increases in both OD at 750 and chlorophyll-a content at 8 ppb (parts per billion) concentration on the 7th day were observed in Chlorella vulgaris. However, total SOD (superoxide dismutase) and GR (glutathione reductase) enzyme activity of A. platensis cultures did not display any alteration in all concentrations, SOD activity displayed an increase significantly at 2 ppb concentration, and GR activity showed increases at 1, 2, and 4 ppb concentrations in C. vulgaris application. In A. platensis application, APX (ascorbate peroxidase) activity decreased at 0.50 ppb, 1 ppb, and 1.5 ppb concentrations. In addition, C. vulgaris application showed decreases at all concentrations. When MDA content increased at all concentrations, the H2O2 content increased only at significatly 0.125 ppb concentration in A. platensis cultures. Both MDA (malondialdehyde) and H2O2 (hydrogen peroxide) content of C. vulgaris cultures showed a statistically significant decrease at all concentrations compared to control. Free proline decreased at 0.25 ppb, 0.50 ppb, 1 ppb, and 1.5 ppb concentrations in A. platensis application, and it decreased at all the concentrations of C. vulgaris application. It concluded that this compound has inhibition effects on A. platensis, but it supports growth in C. vulgaris. Therefore, this synthesized phthalocyanine compound (SPC) should be consumed carefully, and the contamination to aquatic ecosystems should be prevented.

Synthesis, characterization and investigation of algal oxidative effects of water-soluble copper phthalocyanine containing sulfonate groups.

In this study, the chemical and algicidal properties of the newly synthesized compound (2) were evaluated and its algal oxidative effects were determined in Arthrospira platensis and Chlorella vulgaris. First, we have reported on the synthesis and characterization of highly water-soluble copper (II) phthalocyanine (2), containing sodium 2-mercaptoethanesulfonate (2) substituents at the peripheral positions. Some spectroscopic techniques were used to characterize the new synthesized compound (2). In terms of biological properties, C. vulgaris were more tolerance to compound (2) than A. platensis depending to growth parameters. When SOD (Superoxide dismutase) activity significantly increased at 0.25 ppb and 1.5 ppb concentrations in A. platensis cultures, it increased at 6 ppb concentration in C. vulgaris cultures. GR (Glutathione reductase) activity decreased at 1 ppb and 1.5 ppb concentrations while APX (Ascorbate peroxidase) activity did not show a significant change at any concentrations in A. platensis cultures. GR activity showed a significant increase at 6 ppb concentration, while APX activity increased at all concentrations compared to control in C. vulgaris cultures. MDA (malondialdehyde) and H2O2 content decreased at 1 and 1.5 ppb concentrations but there were significant increases in the proline content at all concentrations compared to the control in A. platensis. MDA, H2O2 and free proline contents showed a significant increase at 0.5 ppb concentration in C. vulgaris. In conclusion, compound (2) have algicidal effects, and also it causes to oxidative stress in these organisms.

Synthesis, characterization, and determination of genotoxic effect of a novel dimeric 8-hydroxyquinoline Cd(II) SCN complex.

In this study, a Cd(II) complex was synthesized using 8-hydroxyquinoline and thiocyanate as the ligands and structurally characterized with the combination of FTIR, 1H-NMR, 13C-NMR, UV-vis, and MS spectral data. Then, genotoxic effects of the prepared complex were investigated. Genotoxic properties of the dimeric 8-hydroxyquinolinthiocyanatoCd(II) [Cd2(8Q)2(SCN)2] complex synthesized as drug raw material were analyzed in human peripheral blood lymphocytes. Concentrations of 1, 2, 4, 6, and 8 µg/mL [Cd2(8Q)2(SCN)2] were used for 24 and 48 h durations. [Cd2(8Q)2(SCN)2] significantly increased chromosomal aberrations (CAs) at 4, 6, and 8 µg/mL concentrations after a 24- h period and 2 and 4 µg/mL after a 48-h period. [Cd2(8Q)2(SCN)2] significantly decreased the mitotic index (MI) at all concentrations, both at 24 and 48 h. Micronuclei frequency (MN) was not affected by [Cd2(8Q)2(SCN)2] treatment compared with the control. After application for a 48 h period, 6 and 8 µg/mL concentrations showed toxic effects both in chromosomal abnormality and in micronucleus tests. It also decreased the cytokinesis-block proliferation index (CBPI), but this result was statistically significant only at 6 and 8 µg/mL concentrations. In the comet assay (single-cell gel electrophoresis (SCGE)), significant increases in comet tail length, tail moment, and tail intensity were observed at all concentrations. [Cd2(8Q)2(SCN)2] displays clastogenic effect in the concentrations used in human peripheral lymphocytes at chromosomal abnormality, micronucleus tests, and cytokinesis-block proliferation index parameters. Further studies should be conducted in other test systems to evaluate the complete genotoxic potential of [Cd2(8Q)2(SCN)2].