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Öğe ACUTE AND SOME CHRONIC EFFECTS OF NICKEL IN GAMBUSIA HOLBROOKI(Parlar Scientific Publications (P S P), 2020) Dumlu, Ahmet Burak; Guner, UtkuNickel, which has a wide usage area throughout history, spreads throughout the ecosystem. Although Ni is low in the ecosystem, its usage continues to increase due to human use. Nickel is used in different industrial areas and released into nature from the atmosphere, from underground and above groundwater resources to aquatic ecosystems through erosion. Acute and some chronic toxic effects of Ni on Gambusia holbrooki, mosquito biological control fish, were investigated. Acute toxicity of Ni was determined by the probit analysis method and 96 hour lethal dose test result was 6.811 mg/l for G. holbrooki .During acute and chronic toxicity experiments, some behavioral changes in concentration, water column distribution, clustering and mobility and some physical changes such as blood supply to the gills and blackening of the outer epithelial tissue were observed in test animals.Öğe BIOACCUMULATION OF SOME HEAVY METALS IN FRESHWATER CRAYFISH(Nova Science Publishers, Inc, 2010) Guner, UtkuAnthropogenic inputs of pollutants such as heavy metals into the marine environment have increased their levels to a large extent within the past few decades. The available literature on heavy metal bioaccumulation by freshwater crayfish has been analysed. A very uneven data distribution was found; Orconectes, Cambarus Procambarus and Astacus are the most commonly investigated orders of crayfish. Furthermore, Zn, Cu, Pb and Cd are the most intensively researched heavy metals, and only infrequently are investigations of other metals documented. At some conditions bioaccumulation levels of some heavy metals were as follows Mn> Zn >Cu>Ni>Cr>Pb>Cd. Accumulated metal concentrations are interpreted in terms of different trace metal accumulation patterns, dividing accumulated metals into two components - metabolically available metal and stored detoxified metal. The following chapter will focus on the bioaccumulation of some heavy metals in freshwater crayfish.Öğe Cadmium Bioaccumulation and Depuration by Freshwater Crayfish, Astacus leptodactylus(Foundation Environmental Protection & Research-Fepr, 2010) Guner, UtkuThe freshwater crayfish Astacus leptodactylus (Eschscholtz 1823) is naturally and widely distributed in the lakes, ponds and rivers throughout Turkey. They are omnivorous and thus are open to toxicant exposure from a variety of sources including the water column, adsorbed onto foodstuff by bioaccumulation prey. Crayfish can serve as an excellent model species to increase the knowledge base for invertebrate ecotoxicology. Cadmium bioaccumulation and depuration in the various tissues of the crayfish Astacus leptodactylus were investigated. Adult specimens were exposed to 0.1, 0.5, and 1.0 mg Cd/L under static conditions for three weeks. At the end of the 3(rd) week, the specimens were divided into three groups and transferred into dechlorinated water for either 1,2 or 3 weeks for depuration. After 7, 14, and 21 days, four crayfish from each group were sacrificed and were dissected into their hepatopancreas, gill, abdominal muscle and exoskeleton tissues for evaluation of Cd accumulation. The following accumulation pattern was obtained in decreasing order; hepatopancreas > gills > exoskeleton > abdominal muscles with values of 118.33, 661.63, 39.47, and 3.77 mg/L, respectively. Based on the present work we have concluded that crayfish have a great potential for rapid accumulation and depuration of Cd in fresh water.Öğe Effects of Arsenate and Arsenite on Germination and Some Physiological Attributes of Barley Hordeum vulgare L.(Springer, 2014) Sanal, Filiz; Seren, Gulay; Guner, UtkuArsenic (As) is toxic to plants and animals. We tested the effects of arsenite and arsenate (0-16 mg/L) on seed germination, and on relative root and shoot length, alpha-amylase activity, reducing sugars and soluble total protein contents, and malondialdehyde content in barley seedlings. We also measured As accumulation in barley stems and roots. The alpha-amylase activity, relative root and shoot length, and seed germination decreased with increasing concentrations of arsenate and arsenite. The reducing sugars content in barley seedlings increased after 4 days of growth on media containing As. In general, the protein content in roots and seedlings decreased with increasing doses of As. Arsenic in the tissues was quantified by hydride generation-atomic absorption spectrophotometry. To confirm the accuracy of the method, we analyzed the certified reference material WEPAL-IPE-168. The limit of detection was 1.2 mu g/L and the relative standard deviation was < 2.0 %.Öğe Freshwater crayfish Astacus leptodactylus (Eschscholtz, 1823) accumulates and depurates copper(Springer, 2007) Guner, UtkuCu accumulation and depuration in various tissues of the crayfish Astacus leptodactylus was investigated. Adult specimens were exposed to 0.5, 2.5 and 5.0 mg Cu/L under static conditions for three weeks. At the end of the 3rd week the specimens were divided into three groups and left in dechlorinated water for either 1, 2 or 3 weeks for depuration. After 7, 14 and 21 days, four crayfish from each group were instantaneously sacrificed. All crayfish were dissected into their hepatopancreas, gill, abdominal muscle and exoskeleton tissues for evaluation of Cu accumulation in each. The following accumulation pattern was obtained in decreasing order; hepatopancreas > gills > exoskeleton > abdominal muscles with values of 94.13, 84.86, 66.13 and 11.43 mg/L, respectively. The observed Cu depuration throughout the study was found to be time-dependent. Based on the present work we conclude that crayfish has a great potential for rapid accumulation and depuration of Cu in fresh water.Öğe Genotoxic Effect and Carcinogenic Potential of a Mixture of As and Cd in Zebrafish at Permissible Maximum Contamination Levels for Drinking Water(Springer International Publishing Ag, 2016) Doganlar, Oguzhan; Doganlar, Zeynep Banu; Muranli, Fulya Dilek Gokalp; Guner, UtkuCurrently, the toxic effects and carcinogenic potential of individually treated arsenic (As) or cadmium (Cd) are well documented both in animal and human tissues. However, there are no data focusing on the genotoxicity of these heavy metals as a mixture at the very low concentrations of permissible limits for drinking water. In this study, we examine the genotoxicity and carcinogenic potential of single and combined treatments of As and Cd, as well as attempt to elucidate the mechanism of action of certain cell defense systems such as antioxidants, gene repair, heat shock, cell cycle control, and the apoptosis pathway. Zebrafish (Danio rerio), reared under controlled conditions with artificial diets, were treated with As and Cd, either individually or in combination, at concentrations commonly found in water (10 ppb for As and 5 ppb for Cd) and tenfold higher concentrations for 48 h. Our results indicate that separately, As and Cd treatments at low dose selectively induce antioxidant enzymes, gene repair, and caspaseindependent apoptosis in gill tissue, by targeting the mitochondria, leading to oxidative stress and sub-lethal levels of DNA damage. However, tenfold higher (100 ppb As + 50 ppb Cd) treatment caused significant downregulation of genes involved in double-strand break repair and molecular chaperone genes. Additionally, the highest BCL2/BAX ratio (1.6) and lowest expression levels of caspase-3 (8.4-fold) in all treated groups were observed in same condition. These results demonstrate that both single and combined exposure to As and Cd at permissible levels is potentially safe and causes repairable genotoxicity in gill tissue. However, the highest concentration is potentially carcinogenic due to ineffective DNA repair and insufficient apoptosis.Öğe The genotoxic effects of mixture of aluminum, arsenic, cadmium, cobalt, and chromium on the gill tissue of adult zebrafish (Danio rerio, Hamilton 1822)(Taylor & Francis Ltd, 2022) Gokalp, Fulya Dilek; Doganlar, Oguzhan; Doganlar, Zeynep Banu; Guner, UtkuThe aim of this study is to investigate the genotoxic effects of mixtures of five metals on zebrafish at two different concentrations; at the permissible maximum contamination levels in drinking water and irrigation waters. The drinking water limits are as follows: 300 mu g/L for Aluminum (Al+3), 10 mu g/L for Arsenic (As+3), 5 mu g/L for Cadmium (Cd+2), 10 mu g/L for Cobalt (Co+2), and 50 mu g/L for Chromium (Cr+2). The irrigation water limits: 5000 mu g/L for Al+3, 100 mu g/L for As+3, 10 mu g/L for Cd+2, 50 mu g/L for Co+2, and 100 mu g/L for Cr+2. The zebrafish underwent chronic exposure for periods of 5, 10, and 20 days. The gene expressions for mitochondrial superoxide dismutase (SOD2), stress-specific receptor protein NCCRP1, the heat shock proteins: Hsp9, Hsp14, Hsp60, Hsp70, DNA repair (XRCC1 and EXO1), and apoptosis (BOK and BAX) were evaluated. It was found that exposure to the low- and high-concentrations of the heavy metal mixtures caused cell stress, an increased expression of the antioxidant genes, and repair proteins. As the duration of exposure was increased, the cells progressed through the apoptotic pathway. This was more evident in the high-concentration exposure groups. The results demonstrated the necessity for a reevaluation of the maximum values of heavy metal and toxic element concentrations as prescribed by the Local Standing Rules of Water Pollution Control Regulation, as well as a reevaluation of the limitations of heavy metal mixture interactions with respect to ecological balance and environmental health.Öğe Heavy metal effects on P, Ca, Mg, and total protein contents in embryonic pleopodal eggs and stage-1 juveniles of freshwater crayfish Astacus leptodactylus (Eschscholtz, 1823)(Tubitak Scientific & Technological Research Council Turkey, 2010) Guner, UtkuTo determine the potential biochemical effects of heavy metal pollution on aquatic organisms, pleopodal eggs, and stage-1 juveniles of the freshwater crayfish, Astacus leptodactylus (Eschscholtz, 1823), was exposed to a non-essential (Cd) and an essential (Cu) metal, either singly or in combination. Three different sublethal doses (0.1, 0.5, and 1 ppm) and 1 interaction dose (0.1 ppm Cu + 0.1 ppm Cd) were used to evaluate the accumulation and toxicity. The effects of 2 doses of metals on P, Ca, total protein, and Mg contents in the embryonic pleopodal eggs and in stage-1 juveniles were examined by an autoanalyzer. The same analyses were also performed on recently spawned eggs through the transition to the first juvenile stage (3 weeks). Ten eggs or stage-1 juveniles were sampled during the 3-week period to measure the bioaccumulation of metals. Cd and Cu levels in the eggs and recently spawned eggs were determined by flame atomic absorption. spectrophotometer (FAAS). The results showed that both Cd and Cu accumulated in eggs and in stage-1 juveniles. The results also indicated that metal interactions also occurred, which in this case were probably antagonistic. A comparison of the effects of Cd alone with those of Cd+Cu in combination showed that the mixture was more toxic than Cd alone, but not more toxic than Cu alone. Cd also affected the Ca level in the eggs. The level of Mg increased, while the levels of P, Ca, and total protein decreased in pleopodal eggs exposed to different doses of Cu and Cd. All biochemical parameters and protein levels measured were affected by both metals.Öğe Induction of micronuclei and nuclear abnormalities in erythrocytes of mosquito fish (Gambusia affinis) following exposure to the pyrethroid insecticide lambda-cyhalothrin(Elsevier Science Bv, 2011) Muranli, Fulya Dilek Gokalp; Guner, UtkuIn the present study the induction of micronuclei (MN) and nuclear abnormalities (NA) in erythrocytes of mosquitofish (Gambusia affinis) (Baird & Girard 1853) was studied. Fish were exposed to three different concentrations of lambda-cyhalothrin (LCT) (1 x 10(-4) mu g/l, 2 x 10(-4) mu g/l, 4 x 10(-4) mu g/l) for periods of 6, 12, 24, and 48 h. NA (notched, lobed, blebbed nuclei), MN, bi-nucleated cells, and the ratio of polychromatic erythrocytes (PCEs) to normochromatic erythrocytes (NCEs) were evaluated to assess genotoxicity and cytotoxicity. LCT significantly induced MN and NA in erythrocytes of G. affinis. The PCE/NCE ratio was also decreased after 24- and 48-h treatments of 4 x 10(-4) mu g/l LCT. The results show that LCT has genotoxic and cytotoxic potential on G. affinis. (C) 2011 Elsevier B.V. All rights reserved.Öğe Micronucleus Test, Nuclear Abnormalities and Accumulation of Cu and Cd on Gambusia affinis (Baird & Girard, 1853)(Central Fisheries Research Inst, 2011) Guner, Utku; Muranli, Fulya Dilek GokalpIn the present work the induction of micronuclei (MNi) and nuclear abnormalities (NAs) in erythrocytes and Cu and Cd accumulation in whole body of Gambusia affinis were studied. Fish were exposed to two different Cu and Cd concentrations, 0.1 ppm and 1 ppm, for 1 and 2 weeks periods and to Cu-Cd combination (0.1 ppm Cu + 0.1 ppm Cd) for 2 weeks period using a semi-static renewal system. Micronucleus and nuclear abnormality analysis were carried out on peripheral blood erythrocytes. When fishes were exposed Cu and Cd in combination, Cu accumulation was increased compared to their singly (0.1 ppm) exposed concentrations. Micronucleus and nuclear abnormality analysis tests revealed that, although Cu and Cd did not significantly increase micronuclei frequency, nuclear abnormalities were significantly induced compared to controlÖğe A new record of recently discovered crayfish, Austropotamobius torrentium (Shrank, 1803), in Turkey(Conseil Superieur De La Peche, 2007) Harlioglu, Muzaffer Mustafa; Guner, UtkuAfter the occurrence of Austropotamobius torrentium in the Velika River in European Turkey, investigations to observe the distribution of crayfish species close to the Velika River have been carried out. The present observations showed that the distribution of A. torrentium expanded in European part of Turkey. In the summer of 2006, A. torrentium was found in the Madara. Brook, but the abundance of A. torrentium in this brook was very low in comparison to the Velika River. Under the light of present observations, it could be concluded that besides the limited exploitation interest of A. torrentium in Turkey, this crayfish species increases its distribution in European Turkey, and more research should be carried out on its distribution and its either native or introduced presence in Turkey.Öğe Some morfometric characteristics of crayfish (Astacus leptodactylus Eschscholtz, 1823) in Lake Terkos(Ege Univ, Fac Fisheries, 2006) Guner, UtkuThis study was carried out to determine some morphological characteristics and the relationships between length-weight of the freshwater crayfish, (Astacus leptodactylus Eschscholtz 1823) in Terkos lake. The study was performed between August 2000 and July 2001. Differences of sex groups were also investigated. Results of the research can be summarized as follows; average total length 121.33 mm, average total weight 52.25, average cephalothorax length 59.61 mm, average abdomen length 31.51 mm, average abdomen width 28.7 mm, average cheliped lenght 52.85 mm, average cheliped width 16.53 mm. Length-weight relation equation was found for females y=2.893x-4.321 for males y=2.428x-3.442.Öğe Status of Freshwater Crayfish Distribution in Thrace Region of Turkey(Taylor & Francis Inc, 2010) Guner, Utku; Harlioglu, Muzaffer MustafaThis review focuses on the present distribution of two crayfish species: narrow-clawed crayfish Astacus leptodactylus Eschscholtz and stone crayfish Austropotamobius torrentium (Schrank, 1803) in Thrace region of Turkey. The only known native (indigenous) freshwater crayfish species of Turkey is A. leptodactylus. It is found at more sites than A. torrentium. On the other hand, A. torrentium is only found in Thrace region of Turkey. The first population of A. torrentium was observed in Velika River in 1995. In 2006, the second population of A. torrentium was found in Madara Brook in the region, but the abundance of A. torrentium in Madara Brook was very low in comparison to Velika River. Moreover, further studies carried out in some water resources near the population of A. torrentium, such as DevÖğe TOXIC EFFECTS OF PYRETHRUMS LAMBDA-CYHALOTHRIN AND ALPHA-CYPERMETHRIN ON PEST ARCHIPS ROSANA (LEPIDOPTERA: TORTRICIDAE) AND ITS COMMON PARASITOID(Parlar Scientific Publications (P S P), 2017) Aydogdu, Mitat; Gokalp, Fulya Dilek; Guner, UtkuIn the present study, we aimed to identify the effective concentrations of the insecticides Lambdacyhalothrin (LCT) and Alpha-cypermethrin (CYP) on different live stages of Archips rosana (Linnaeus, 1758), using their commercial forms, Tekvando 5EC (LCT) and Super Takimethrin 100 EC (CYP), as test substances at the field recommended concentration and at 101, 102, 103,104, 105, 106 fold diluted concentrations of the recommended concentration. We found that the LC50 concentrations of LCT for larvae, adult (24 h) and pupae forms (7 days) were 1.162 mu M, 0.919 mu M and 0.012 mu M, respectively. The LC50 concentrations of CYP for larvae, adult and pupae forms were 1.937, 1.014 and 0.008 mu M, respectively. The concentrations that induced over 85% mortality of pupae, although they did not exert a lethal effect on the common parasitoids that developed in the pupae, were 1.10(-1) mu M for LCT and 2.10(-3) mu M for CYP under laboratory conditions. We showed that diluted concentrations of LCT and CYP insecticides still have 80% mortality at the larvae, pupae and adult stages. It is important to study the concentrations that are effective on pests, but not on parasitoids, which are used in biological control. Therefore, this approach may be helpful for integrated pest management programmes.
