The metal content of Agaricus bitorquis, Agaricus bisporus, Armillaria mellea, Hericium erinaceus, Laetiporus sulphureus, Lentinula edodes, Macrolepiota procera, Kuehneromyces mutabilis, Pleurotus eryngii and Pleurotus ostreatus was analysed. The samples were first dried, then ground and pressed into tablets suitable for XRF analysis. The metal contents were compared between the different fungal species. For harvested and laboratory-grown mushrooms, XRF analysis was used to investigate the relationships between the metal concentrations in the substrate and in the substrate. The metal content of purchased mushrooms was compared with the other sample groups. Hericium erinaceus and Pleurotus ostreatus were grown under laboratory conditions on substrates with known concentrations of Cu and Zn. The results were used to describe the correlations between the metal content in the substrate and in the substrate and to observe the effects of high Cu and Zn additions. For both cultivated species, we calculated the BCF, which gave us a better insight into the accumulation capacity of the fungi for Cu and Zn. The average BCF values decreased with increasing concentration of the added metals, indicating a regulation of uptake by the fungi and the existence of an upper limit for metal uptake. The results confirm that the uptake of metals by fungi is limited and does not increase linearly. Furthermore, the inhibitory effect of zinc on the growth of Hericium erinaceus was analysed by a screening test on PDA medium with known Zn concentrations.
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