Indigenous bacteria as potential agents for trace metal remediation in industrial wastewater

Water pollution is a burning issue that can originate from both urbanization and industrialization. This study aimed to evaluate the industrial wastewater collected from Hayatabad Industrial Estate and to use indigenous bacteria, Pseudomonas aeruginosa and Enterobacter aerogenes for bioremediation. The water samples collected were analyzed for physicochemical parameters and microbial pollution. To analyze the pollution removal efficiency by indigenous bacterial species, a pot experiment was performed for 14 days. Before and after experiment, the water samples were analyzed for trace metal concentration by Atomic Absorption Spectroscopy. The biochemical and molecular analysis confirmed the presence of two bacterial species (P. aeruginosa and E. aerogenes). The industrial wastewater treated with these isolated bacterial species showed significantly decreased level of electrical conductivity (42.33-86.45%), dissolved oxygen (16.35-63.37%), biological oxygen demand (33.33-80.62%), chemical oxygen demand (00-83.52%), total suspended solids (00-80%), and total dissolved solids (0.00-54.93%). The P. aeruginosa removal efficiency for Cu, Cd, and Pb was ranging 77.58-82.35%, 19.67-50%, and 20.40-91.66%, respectively. Similarly, the E. aerogenes removed Cu, Cd, and Pb in the range of 47.05-60.61%, 54.55-62.29%, and 85.21-91.6%, respectively. Phytotoxicity results revealed that the wastewater treated with both P. aeruginosa and E. aerogenes gives better Triticum sp. % germination rate, leaf length, and root and shoot weight. The highest plant % germination was showed by treated P. aeruginosa in control (100%), followed by E. aerogenes in control (100%). The t- test analysis showed the concentration of trace metals (TM) in industrial wastewater was significantly reduced (p ≤ 0.05) by bacterio-remediation. The study concluded that both bacterial species are active in the removal of pollution and TM from the wastewater.