Alişer, Ahmet Bedrettin; Aydin, Rahmi; Serdar, Osman

The biochemical reactions of zebra mussels Dreissena polymorpha (Pallas, 1771) exposed to different concentrations of cadmium (Cd) in the acute period (24 and 96 hours after treatment) were studied. Four variants of experimental treatment were examined: 0 μg/L Cd (control), 10 μg/L Cd, 20 μg/L Cd and 40 μg/L Cd. Changes in the enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) levels were determined using ELISA kits. In D. polymorpha exposed to the three experimental concentrations of cadmium, there was a statistically significant decrease (p<0.05) in SOD enzyme activity with increasing concentration or exposure times. No change was observed in CAT enzyme activity with increasing concentrations. The decrease in the activity depending on the exposure times was not statistically significant (p>0.05). As for GPx enzyme activity, a significant increase was detected after Cd application compared to the control (p<0.05). TBARS and GSH levels increased significantly in all Cd application groups compared to the control at 24 and 96 hours. The effects of different concentrations of Cd on D. polymorpha in the acute period were associated with changes in SOD, CAT, GPx enzyme activities. TBARS and GSH levels were effective parameters in determining the oxidative damage caused by Cd.

İncele

Yildirim, Nuran Cikcikoglu; Serdar, Osman; Derman, Taner

The combined toxicity of polycyclic aromatic hydrocarbons on freshwater amphipod Gammarus pulex was investigated. The 14-day LC50 values of fluoranthene, phenanthrene and their combination for G. pulex were determined as 5.88±0.23, 8.31±0.57 and 7.00±0.33 mg/L, respectively. To evaluate the single and combined toxicity, sublethal concentrations of fluoranthene, phenanthrene and their combination were exposed to G. pulex for 14 days. Acetylcholinesterase, glutathione-s-transferase and cytochrome P450 1A1 enzymes were measured as biomarkers. Acetylcholinesterase activities showed significant inhibition at the end of 7 and 14 days. No statistically significant change was observed in cytochrome P450 1A1 levels at the end of the 7th day, but a significant increase was detected at the end of the 14th day. A significant inhibition was observed in glutathione-s-transferase activities at the end of the 7th and 14th days. Statistically significant changes were observed in all parameters when the application times are compared. It was determined that G. pulex exposed to different concentrations of phenanthrene and fluoranthene individually and in combination caused significant changes in activites of the all measured enzymes. It was concluded that the cytochrome P450 1A1, glutathione-s-transferase and acetylcholinesterase enzymes in G. pulex are useful biochemical markers for the determination of polycyclic aromatic hydrocarbon toxicity.

AtıfScopus3

İncele

Söylemez, Hilal; Serdar, Osman

This study aimed to determine the relationship between temperature and neurotoxicity of a new generation insecticide, the active ingredient of which is flubendiamide, on non-target aquatic organisms (Gammarus pulex (L., 1758)). Firstly, LC50 values of flubendiamide on G. pulex were determined at 16, 18 and 20 °C as 256.83 ± 19.59 µgL-1, 169.38 ± 34.17 µgL-1 and 155.84 ± 17.22 µgL-1, respectively. We found that the acute toxicity sensitivity of the test organism to the pesticide containing flubendiamide increased with increasing temperature. Secondly, G. pulex was exposed to non-lethal concentrations of flubendiamide pesticide for 96 hours at the above temperatures. Finally, the changes in acetylcholinesterase (AChE) enzyme activity were determined for each temperature using ELISA kits. The exposure time between the 24th and 96th h at the same temperature was found to be statistically insignificant (p>0.05). It was determined that the inhibition value of AChE enzyme activity on the test organism of the pesticide with active ingredient flubendiamide increased depending on the temperature increase. Considering the changes in AChE enzyme activities in G. pulex at different temperatures against flubendiamide insecticide, it was concluded that it can be used as a useful biomarker.

AtıfScopus1

İncele

Saglam, Naim; Özbay, Ozkan; Demir, Timur; Balci, Mustafa; Pala, Aysegul; Kiliç, Ali

The species of the genus Hirudo are threatened but still used worldwide in human treatment. We studied the density changes of southern medicinal leech Hirudo verbana and some water quality parameters monthly during a year in the Akpinar Marsh, Eastern Anatolia, Turkey. Samples of H. verbana were collected using a modified unit square design and unit time collecting method as an indicator for population density. Some water parameters such as water temperature, dissolved oxygen, pH, some cationic elements (lithium, sodium, ammonium, potassium, magnesium, calcium) and anionic elements (fluoride, chloride, sulphate, nitrate, phosphate, bromide) were determined. These parameters were analysed to detect their impact on population density of this medicinal leech. The populations of H. verbena were most dense in May-June; the species was found in smallest numbers in November and hibernating in December-March. A significant correlation (p<0.05) between the number of medicinal leeches in the unit area and monthly water temperature, amount of ammonium and fluoride was determined using the Pearson correlation coefficient. In the Akpinar Marsh, the largest adult medicinal leeches (>5 g) in the fourth size group formed 12.50-27.50% of the population and the smallest (<1.0 g) in the first size group formed 7.50-38.24%.

AtıfWoS3

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