Indentification of tolerance threshold of Agaricus bisporous to Cr3

In the present research the effect of different concentrations of Cr3+ on growth and uptake of chromium by mycelium of Agaricus bisporus was investigated. Chromium playes an important role in improvment of insulin action in diabetic patients. The aim of this research was to investingate tolerance threshold of the fungus to Cr3+ concentrations. Mycelium of A. bisporus was cultured in solid media (PDA) and liquid media (MEB). Cr3+ concentrations in the rang of 0 – 400 ppm were added to the culture media at 25C and pH=6. Increasing of Cr3+ concentration more than 150 ppm decreased growth parameters including growth of colony diameter of the fungus and mycelium dry weight. Accumulation of chromium in mycelium was increased and at highest concentration (300 ppm Cr3+) chromium content of the mycelium was determined to be 12.73 ppm. Increasing Cr3+ concentration more than 150 ppm caused significant reduction of k+ uptake. Alghough no significant effect on Na+ absorption by mycelium was observed. On the base of the results, tolerance threshold of mycelium of A. bisporus to Cr3+ appeared to be 150.