Heavy Metal Tolerance and Toxicity Studies on- Indigenous Microflora and its Application for Bioremediation

Abstract

Heavy metal (HM) contamination is a persistent environmental problem in many countries. Pesticides, organic compounds, paints, industrial and mining waste, and heavy metals (HMs) are the primary drivers of soil pollution. It is critical to clear up soils contaminated by HMs. It is beneficial to investigate the areas of HM bioremediation employing hybrid technologies, genetically engineered microorganisms with improved bioremediation potential techniques. In the present study three abundantly growing indigenous microbial isolates (Bacteria- Rhizobium and Azotobacter and Fungi- Aspergillus) were cultured using suitable growth media to obtain large biomass. These indigenous species have ability to grow in mass quantity under ideal conditions at minimal efforts. The isolates were then tested for their tolerance to heavy metals Cr, Hg, Cu, Zn, and Mg under experimental settings using MIC and the broth dilution technique at various concentrations (100,300 and 500ppm for bacteria and additionally 1000,3000 and 5000ppm for fungi). All the three isolates showed various degree of tolerance for selected heavy metals. Aspergillus fumigatus responded best among all.