ماندانا زارعی

Background:over thelast few decades, special attention to the management of environment pollution due to dangerous material like heavy metals. Today, pollution due to heavy metals becomes one the most important environmental problems. Physiochemical methods inorder to desorb heavy metals are expensive and not useful. So over the last few years purification of heavy metals by biological method have received much attention. Aim:the purpose of this research is bisorption of vickel by Luteimonas sp. Bacteria. Methodology:in this research,10 strains of native Persian Gulf bacteria that previously isolated purified and liophilized were used, then after cultive in different culture medium such as nutrient agar and nutrient broth and incubator them. Bacteria whose colonies were able to grow at high nickel concentration were selected as nickel resistsnte bacteria. Then the growth chart of Luteimonas sp.and Pseudomonas geniculataat concentrations of 0, 0.25, 0.5 and 1 g/l nickel sulfate as well as growth chart of Luteimonas sp.at concentrations of 0.05, 0.15, 0.25, 0.35, 0.5 and 1 g/l of cadmium nitrate was drown. Next, MIC testing of nickel metal for both Luteimonas sp. and Pseudomonas geniculataand MICtesting of cadmium metal for Luteimonas sp. done.Then for initial evaluation of biosorption of nickel, wet and dry biomass of Luteimonas sp. was used. The experimient was designed using Design Expert software inorder to biosorption and also optimization of nickel biosorption. The software provided 30 treatment based on pH, contact time, metal concentration and adsorbent concentration. Treatment were prepared according to software parameters, then their atomic absorption was read. The optimization was performed by the software according to the minimize atomic absorption. Two bacteriaLuteimonas sp. and Pseudomonas geniculatathe most resistance to nickel and were selected for further studies.Growth chart of both Luteimonas sp. and Pseudomonas geniculataat different concentrations