Copper tolerant microfungi for bioremediation.

Soil samples were processed to obtain fungi tolerant to copper (copper sulphate) using poisoned food technique. Control media as well as media supplemented with 40ppm, 200ppm and 400ppm concentrations of copper (in the form of CuSO4) were used to isolate fungi by serial dilution plate method. In total, 17 species of fungi were isolated. Out of these, six species i.e., Penicillium sp. BG, Penicillium sp. DG, Aspergillus sulphureus, Aspergillus niger, Fusarium moniliforme and Trichoderrjia lignorum could tolerate the highest concentration i.e. 400ppm. Penicillium sp. BG flourished more on media containing 400 ppm copper sulphate as compared to normal media. In addition to the above six fungal strains, Penicillium implicatun was moderately tolerant as judged by their appearance on the media containing copper sulphate @200ppm. Penicillium citrinum was only moderately resistant. Aspergillus luchuensis, Aspergillus ustus, Sepedonium chrysospermum and Scopulariopsis communis could not tolerate even low concentrations of copper sulphate (40 ppm). Out of these 17 species, 7 fungal species were selected to study the effect of different concentrations of copper sulphate on the in vitro growth of individual species. Aspergillus sulphureus, Aspergillus niger and Penicillium sp. BG appeared to be copper tolerant fungal species. Thus, these species can be further tried for their utilization as biosorbents for remediation of copper in the effuents.