Biosorption of Mercury from Industrial Effluent by Fungal Consortia

Mercury is present in different types of industrial effluents that cause environmental pollution. Conventional methods such as precipitation, oxidation/reduction, ion exchange, filtration, membranes, and evaporation are extremely expensive or inefficient for the removal of mercury from diluted solutions. In this context, the biosorption process has recently been shown to be an effective and economical method. The present work describes the mercury biosorption ability of three fungi, i.e., Aspergillus niger, Trichoderma viride, and Humicola insolens. Monocultures of these strains and 10 different combinations were investigated. The consortium of 24-h-old H. insolens and 48-h-old of A. niger and T. viride in equal ratio was found to be compatible. This consortium decreased the residual mercury from 2.02 to 0.001 μ g/L after 7 days of incubation, and caused a significant reduction in chemical oxygen demand (COD) (92.6%) from an initial level of 21 mg/L.