Sevgi DEMİREL, Beyza ÜSTÜN, Belma ASLIM, Ebru ŞEBNEM YILMAZ

Toxicity of ındividual/combined effect of zn+2, fe+2, cu+2 to synechocystis sp. e35 ısolated from Küçükcekmece lagoon, İstanbul

Küçükçekmece 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+2ve metal karışımlarının (Zn+2-Cu+2, Zn+2-Fe+2, Fe+2-Cu+2ve Fe+2-Cu+2-Zn+2) etkisi araştırılmıştır. Tekli uygulamalarda metallerin toksisiteleri sırasıyla Cu+2> Zn+2>Fe+2’dır. Metallerin EC50 değerleri ise sırasıyla 6.94, 13.92 ve 3.42 mg/l (Zn+2, Fe+2, Cu+2)’dir. Ayrıca, üçlü metal kombinasyon uygulamalarının da güçlü inhibitör etki gösterdiği tespit edilmiştir (EC10= 0.02 mg/l; EC50 =2.93 mg/l).

İstanbul Küçükçekmece gölünden izole edilen synechocystis sp. e35 üzerine zn+2, fe+2ve cu+2metallerinin tekli /kombine bileşiklerinin toksisitesi

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+2and of metal mixture (Zn+2-Cu+2, Zn+2-Fe+2, Fe+2-Cu+2and 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+2in growth media. The EC50 values of the Zn+2, Fe+2, Cu+2on 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.

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