Preliminary Bioleaching of Heavy Metals from Contaminated Soil Applying Aspergillus niger F2

Abstract

A new strategy of heavy metal biobleaching was proposed based a fungal strain identified as Aspergillus niger and named F2. F2 displayed great ability of heavy metal resistance and organic acid production. The temperature, pH, carbon source, and nitrogen source have great influences on the heavy metal bioleaching from contaminated soil by F2. The optimum temperature and pH for biobleaching were 30°C and 5.0, respectively. The total heavy metal bioleached by F2 with sucrose, glucose, maltose, lactose and starch as carbon source were 69.86%, 66.57%, 64.59%, 0.92%, and 69.01%, respectively, while the total heavy metal bioleached by F2 with NaNO ₃, NH₄NO₃, peptone, and yeast extract as nitrogen source were 64.10%, 64.05%, 65.87% and 66.27% individually. Our finding provided a new perspective for the treatment of heavy metal contaminated soil.