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    Antioxidant enzymatic defences during embryogenesis of rainbow trout Oncorhynchus mykiss (Walbaum 1792)
    (Central Fisheries Research Inst, 2015) Zengin, Hatayi; Yılmaz, Ökkeş; Demir, Ersin; Gökçe, Zehra
    In this study antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHpx), glutathione reductase (GR) and glutathione S-transferase (GST) were investigated in unfertilized and fertilized eggs, 12, 22 and 32 day embryos of rainbow trout Oncorhynchus mykiss (Walbaum 1792). Vitamin E, lipid peroxidation products and fatty acids levels were also determined. A significant decrease in vitamin E level was found in fertilized eggs of O. mykiss. In contrast, the level of malondialdehyde (MDA) was very high in fertilised eggs and 12 day embryo. The PUFA contents in fertilized eggs and 12 day embryo were found to be lower than in the other embryonic stages. Measurable amounts of all the SOD, CAT, GSHpx, GR and GST enzymes activities were present in O. mykiss eggs and embryos. The most intense decrease was detected in the activities of SOD, GR and GST in fertilized eggs, whereas the most intense increase in the CAT activity was detected in the same stage of O. mykiss. GSHpx activity showed a significant increase in fertilized eggs and in 32 day embryos before hatching. GST activity showed the most significant increase in 22 day embryos of eyed eggs stage. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.
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    Antioxidant Enzyme Activities and Some Biochemical Changes in Rainbow Trout Oncorhynchus mykiss (Walbaum 1792) Yolk-Sac Larvae
    (CENTRAL FISHERIES RESEARCH INST, 2016) Zengin, Hatayi; Yilmaz, Okkes; Gokce, Zehra; Demir, Ersin
    In this work we studied the biochemical status of antioxidant defences of yolk-sac larvae from the commercial fish, rainbow trout Oncorhynchus mykiss (Walbaum 1792) over a period of 19 days from hatching. The parameters studied were: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHpx), glutathione reductase (GR) and glutathione Stransferase (GST). Oxidative damage was measured by the formation of malondialdehyde (MDA). Our results showed that the presence of catalytic activities was observed from hatching day and significant changes in the enzymes were seen in the 12 and 19 days yolk-sac larvae, when the larvae finished their endogenous feeding. Our study indicates that catalase activity sharply increased in the 12 and 19 days post-hatch but superoxide dismutase activity sharply decreased in the same period. Glutathione peroxidase regularly decreased with age throughout the 19-day study period. Glutathione reductase showed a significant increase in the 12 and 19 days yolk-sac larvae. There were no significant changes in glutathione S-transferase activity throughout the yolk-sac stage. When the egg yolk-sac was reabsorbed, the total protein content sharply decreased at day 19. The PUFA contents in the 12 and 19 days yolk-sac larvae were found to be higher than in the other yolk-sac stage.
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    Effect of vanillic acid against oxidative stress induced by glyphosate in Saccharomyces cerevisiae
    (Ersin YÜCEL, 2019) Özcan, Gözde; Demir, Ersin; Yılmaz, Prof. Dr. Ökkeş; Erişir, Figen Erdem; Zengin, Hatayi
    Glyphosate is a widely used broad-spectrum herbicide. Vanilic acid is a phenolic acid found naturally in many plants. In this study, the effect of vanilic acid against oxidative stress induced by glyphosate in Saccharomyces cerevisiae was investigated. S. cerevisiae was proliferated and developed in YEDP medium. Both glyphosate and vanilic acid were added to the development environment of Saccharomyces cerevisiae to be 200, 400 and 800 mg per liter. At the end of the experiment, Saccharomyces cerevisiae samples (Reduced glutathione (GSH), oxidized glutathione (GSSG), Malondialhedit (MDA), fatty acid, E, D, K vitamins and phytosterol) were analyzed in HPLC and GC devices. Antioxidant potential of vanillic acid was also identified. In this study, the effect of vanillic acid against oxidative stress and toxicity caused by glyphosate in S. cerevisiae was investigated for the first time. In S. cerevisiae administered glyphosate, there were statistically significant changes in MDA, GSH, GSSG, protein, fatty acid, E, D, K vitamins and phytosterol levels, but the vanilic acid applied was detected statistically significantly reduced the changes in these parameters. As a result of analysis by gas chromatography, the yeast cell of octanoic acid (8: 0), lauric acid (12: 0), myristic acid (14: 0), palmitic acid (16: 0), palmitoleic acid (16:1 n-7), stearic acid (18: 0), oleic acid (18:1 n-9) and linoleic acid (18:2 n-6) acids were observed. Vitamin D, E and K were analyzed with HPLC device. As a result of this analysis, molecules such as K2, δ-tocopherol, D2, D3, α-tocopherol, ergosterol, K1, stigmasterol, β-sitosterol were identified. Biochemical analysis showed that cell density in culture medium containing 800 mg per liter of glyphosate decreased. It was found that vanilic acid showed beneficial effects against oxidative stress caused by glyphosate in Saccharomyces cerevisiae.