Preliminary study of platinum accumulation in the fruitbodies of a model fungal species: king oyster mushroom (Pleurotus eryngii)

A model species of saprophytic fungus, king oyster mushroom (Pleurotus eryngii), was cultivated on barley substrate supplied with (Pt(NH3)4)(NO3)2, under well defined conditions. The samples of the collected fruiting bodies were digested and analyzed for total platinum content by means of ICP-MS. The results proved that platinum is not accumulated in the fruitbodies of Pleurotus eryngii for a wide range of Pt concentrations in the culture substrate (100−1000 ppb Pt in 50 ml of water solution added to ca. 450 g of hydrated barley seeds per container). Observable levels of Pt were only found in the fruitbodies obtained from the medium contaminated with 10000 ppb (10 ppm) platinum solution. This demonstrates significant difference in the effectiveness of platinum extraction in fungi and plants, which are capable to accumulate platinum even when supplied at lower concentration (<500 ppb). It also shows different physiological pathways of platinum and other elements which are easily accumulated in the fruitbodies of the same species.