Sevgi DEMİREL, Belma ASLİM, Beyza USTUN, Ebru Sebnem YİLMAZ

İstanbul Küçükçekmece Gölünden İzole Edilen Synechocystis sp. E35 üzerine Zn+2, Fe+2 ve Cu+2 Metalerinin Tekli /Kombine Bileşiklerinin Toksisitesi

K üçükçekmece gölünün su ve sediment yapısı toksik düzeyde demir,bakır ve çinko bulundurur. Araştırma alanında, belli dönemlerde antropojenik ve abiyotik faktörlere bağlı olarak yoğun alg üremeleri gözlenmiştir. Bunlar içerisinde siyanobakterilerin dominant grup olduğu tespit edilmiştir. Bu çalışmanın amacı, Küçükçekmece Gölünden izole edilen Synechocystis sp. E35 izolatı üzerine çeşitli ağır metallerin toksik etkisinin incelenmesidir. Laboratuar ölçeğinde, Zn+2, Fe+2, Cu+2 ve metal karışımlarının Zn+2-Cu+2, Zn+2-Fe+2, Fe+2-Cu+2 ve Fe+2-Cu+2-Zn+2 etkisi araştırılmıştır. Tekli uygulamalarda metallerin toksisiteleri sırasıyla Cu+2>Zn+2>Fe+2’dır. Metallerin ECmetal kombinasyon uygulamalarının da güçlü inhibitör etki gösterdiği tespit edilmiştir EC10= 0.02 mg/l ; EC50 =2.93 mg/l

Anahtar Kelimeler:

Siyanobakteri, Küçükçekmece Lagünü, Ağır metal

Toxicity of Individual/Combined Effect of Zn+2, Fe+2, Cu+2 to Synechocystis sp. E35 Isolated from Kucukcekmece Lagoon, Istanbul

Iron, copper and zinc at toxic levels were found in water and sediment structure of Kucukcekmece Lake. In the research area, algae blooms have been observed dependent upon anthropogenic and abiotic factors at certain periods. Cyanobacteria species have been observed as dominant microorganism during algae bloom. The objective of the present study is to evaluate the toxic effects of various heavy metals on the Synechocystis sp. E35 isolated from Kucukcekmece Lagoon, Istanbul. Toxicity of Zn+2, Fe+2, Cu+2 and of metal mixture Zn+2- Cu+2, Zn+2-Fe+2, Fe+2-Cu+2 and Fe+2-Cu+2-Zn+2 are investigated in the laboratory scale. The order of toxicity of the metals to the Synechocystis sp. E35 is Cu+2> Zn+2>Fe+2 in growth media. The EC50 values of the Zn+2, Fe+2, Cu+2 on the inhibition of the growth of E35 isolate: are 6.94, 13.92 and 3.42 mg/l, respectively. Besides, combination of ternary metal systems showed stronger inhibitory effect on cells are 0.02 and 2.93 mg/l, respectively.

Keywords:

Cyanobacteria, Kucukcekmece Lagoon, Heavy metal,

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