Bioremediation of Lead (Pb) by using Aspergillus terreus Isolated from Polluted Soil

Industrial effluent causes serious problem to the environment, it contain toxic chemicals such as heavy metals, dyes and other substances which affect water bodies, soil and other parts of the ecosystem. Heavy metals such as Lead (Pb), Cadmium (Cd), Chromium (Cr) and Copper (Cu) are very hazardous to human life, when released through human anthropogenic activities. Methods of removal by physicochemical techniques were found inadequate. Bioremediation procedures can be employed to remove waste products from the environment which is eco-friendly and less cost-effective. Pb-resistant fungus was isolated from the polluted soil. It was grown on Sabouraud Dextrose Broth (SDB) by enrichment method and plated on Sabouraud Dextrose Agar (SDA) and then screened at various concentrations of Pb ions concentrations up to 700mg/L. The 18S rRNA was carried out and based on that Clustal X software was used to identify the isolate as Aspergillus terreus. The uptake of the Pb ions was also carried out and enhanced in the liquid medium by optimization of the conditions which includes pH, temperature, inoculums size and incubation time. The highest Pb removal was found to be 84.63%, with dried biomass of 1.78 mg. Scanning Electron Microscopy revealed the structure of the isolates before and after the treatment with Lead heavy metal. The isolate could be used for the removal of contaminants especially hazardous chemicals and heavy metals from the environment.