Bioremediation of Lead by Indigenous Bacteria Isolated from an Idol Immersion Site (Lead remediation by Pseudomonas)

Heavy metal contamination particularly lead (Pb) is a fast-emerging environmental issue around the globe with special concern in the areas where idol immersion is a major activity. The current study was undertaken to isolate and characterize a lead-resistant bacteria from Prempura Ghat, Bhopal, being one of the major idol immersion sites. From the surface, eleven bacterial colonies were isolated, out of which two demonstrated tolerance up to a significant level with lead concentration. The most tolerant isolate was Pseudomonas sp. designated as PM9 which had a resistance level up to 500 ppm for lead. This bacterium was further grown on lead stress in minimal salt medium over 120 hours. The growth was still maintained with a higher lead concentration. After 72 hours, atomic absorption spectroscopy examination revealed that Pseudomonas had eliminated 61.30 ± 1.0% of the lead, suggesting that it might be used for bioremediation. Investigations into the bacterium's antioxidant defence mechanisms revealed that exposure to lead increased SOD and CAT activity, indicating the bacterium's capacity to cope with oxidative stress. These results reveal Pseudomonas as an excellent candidate for the bioremediation of lead-contaminated water bodies, particularly those impacted by idol immersion episodes.