Bioremediation of Metallic Ions by Eight Penicillium Species

In this paper, eight Penicillium species (P. brasilianum, P. citrinum, P. funiculosun, P. janczewskii, P. janthinellum, P. mineoluteum, P. pinophilum, and P. sclerotiorum), isolated from Brazilian soil, were evaluated for their ability to remove metallic ions as cadmium, cobalt, copper, lithium, lead, and nickel present in aqueous residues. Two bioremediation methodologies were used: growing cells or resting cells. Some of the tested species showed outstanding potential for metallic ions bioremediation. Lead removal was achieved in good yields by using both growing and resting cells methodologies. Using growing cells, in 24 h, removal of nickel by P. janthinellum reached 20.8%. This species was also extremely efficient (91.2%) at biosorption of lead. Using resting cells method, Penicillium species targeted in the present study reached rates of almost 60% removal in only 1 h, being therefore of interest when preferential removal of lead in aqueous solutions is desired. An extraordinary bioremediation was detected using P. brasilianum because 74.4% of lead ion has been removed when this metal was present in a binary mixture containing lithium. Regarding copper, bioremediation using P. sclerotiorum was accomplished in 18.5%. Species P. citrinum and P. janczewskii were able to remove 26% of the copper ions present in the solution. The results show the potential of Penicillium species, a very accessible natural bioresource isolable from soil, water, and plants, to be used in lead and other metals biosorption.