Tolerance and uptake of heavy metals by Trichoderma atroviride isolated from sludge.

A strain of Trichoderma atroviride, isolated from sewage sludge obtained from a water treatment plant located in Madrid (Spain), has been studied for tolerance to heavy metals (copper, zinc and cadmium) and for its capacities to uptake these metals. It was found that this fungus is capable of surviving high metal concentrations, apparently as a result of the natural selection of resistant cells. Also, growth and metal uptake have been assayed in samples where the fungus was cultured in the presence of a single metal and in the presence of a combination of two or three cations, where additive and synergistic interactions were observed. Finally, metal uptake by this strain has been studied under different nutritional conditions. It was found that the highest values of metals removal were achieved for autolysed mycelia while the lowest levels were observed in the presence of glucose.