A Study on Biosorption Potential of Aspergillus sp. of Tannery Effluent

Chromium toxicity is one of the major environmental pollutants. As conventional methods for heavy metal removal are very expensive, bioremediation using fungi is extensively explored. Therefore in the present investigation, out of 23 fungi isolated from tannery effluent, 4 Aspergillus species namely A. terreus, A. tamarii, A. flavus and A. niger were selected for evaluating chromium tolerance and biosorption potential. Growth of the fungi was tested using various concentrations of Potassium dichromate (Cr VI) viz., 1 mM, 3 mM and 5 mM amended in potato dextrose agar. For all the fungi, growth was observed only in 1 mM and 3 mM. No growth was observed in 5 mM. Biosorption efficiency of both live and alkali pretreated Aspergillus species was compared. In the present study, alkali pretreated form exhibited highest biosorption efficiency than the live biomass in which A. terreus showed highest chromium biosorption potential compared to the other fungi.