Bioremediation of Heavy Metals from Tannery Wastewater effluents using bacterial isolates

Bioremediation is a simple and environmentally friendly solution for solving environmental problems. In our study three bacterial strains (IS1, IS2 and IS3) were isolated from tannery wastewater and were identified using biology system Biolog TM microplate as pseudmonas sp., Klebsiella sp. and Enterobacter sp. respectively. These strains were examined for their ability to reduce Pb+2, Cd+2 and Cr+3 in tannery wastewater effluent. Some parameters, such as temperature, pH, and incubation duration, were optimized in order to improve adsorption efficiency of heavy metals. The perfect optimum conditions were found to be temperature of 35°C, pH of 5, and a 48-hour incubation time. Pseudomonas sp. showed the best removal percent 76% and 75% for lead and cadmium respectively while klebsiella sp. showed the highest removal percentage for chromium 74%. A mixture of the three isolated bacterial strains was examined to see whether they could be combined in their heavy metal bio-degradation activity or not, the test revealed synergism between the three isolated strains, with higher removal percentages 78 %, 77% and 78% for Pb+2, Cd+2 and Cr+3 respectively.