<p>Cupriavidus sp. IrC4 is a copper-resistant bacteria isolated from activated sludge in an Industrial Wastewater Treatment Plant in Rungkut-Surabaya, Indonesia. The purpose of this research was to study the potency of Cupriavidus sp. IrC4 as a bioremediation agent for copper, lead, mercury, and cadmium. Resistance of Cupriavidus sp. IrC4 to heavy metals were determined by measuring the minimum inhibitory concentration (MIC). Accumulation of copper, cadmium, and lead were determined by Atomic Absorption Spectrophotometer. Cupriavidus sp. IrC4 showed multiple resistance to heavy metals. The MICs of Cupriavidus sp. IrC4 to copper, lead, mercury, and cadmium were 16 mM, 15 mM, 6 mM, and 5 mM, respectively. The growth of Cupriavidus sp. IrC4 was inhibited by the addition of CuSO4 in the medium. The bacteria survived in the presence of high copper concentration as shown by the extension of the lag phase up to 36 hours. The analysis demonstrated that the copper resistance of the bacteria was facilitated through the accumulation of copper. Cupriavidus sp. IrC4 accumulated up to 367.78 and 260.01 mg/gram dry weight of cells of copper and lead, respectively. The bacteria demonstrated growth in the medium containing the mixture of 0.5 mM copper, lead, cadmium and accumulated those heavy metals up to 0.14, 24.74, and 12.49 mg/g dry weight of cells, respectively. The high resistance and capability of Cupriavidus sp. IrC4 to accumulate heavy metals can be exploited in bioremediation process for removing heavy metals from industrial sewage. </p><p><strong>Keywords</strong>: Accumulation, copper, Cupriavidus sp. IrC4,heavy metals, resistance.</p>
THE POTENCY OF COPPER-RESISTANT BACTERIA Cupriavidus sp. IrC4 ISOLATED FROM INDUSTRIAL WASTEWATER TREATMENT PLANT IN RUNGKUT-SURABAYA AS A BIOREMEDIATION AGENT FOR HEAVY METALS
