Harnessing Aspergillus aculeatus for Lead (Pb) bioremediation from a contaminated dump site in Guwahati, Assam, North-Eastern India

Lead (Pb) contamination in the metropolitan cities of developing countries is a common occurrence due to a major issue of improper waste management system which not only undermine the health of living organisms but also the quality of the soil. This study highlights a naturally adapted strain Aspergillus aculeatus with high metal tolerance from a local heavy metal-contaminated environment. It advances our understanding of the diversity of fungus found in contaminated soils and shows the promise of employing native fungi for environmentally friendly, site-specific bioremediation. Mycoremediation was the approach adopted for this work to treat the Pb contaminated soil by examining the propensity of fungi to absorb Pb. After conducting an initial screening procedure, fungal isolates were obtained and their tolerance index was evaluated by exposing them to different concentrations of Pb (100,200,400,600,800 and 1000 ppm). Results indicated the highest tolerance index at 1000 ppm and the potential for Pb biosorption (≈ 84%) was evaluated by Atomic Absorption Spectroscopy. Aspergillus aculeatus was found to be the potent metallotolerant fungal strain among all the isolated strains. Molecular identification revealed the strain to be Aspergillus aculeatus (OQ980247) and the potential of its biomass as sorbents is indicated by the available data.