The use of Li2O fortified growing compost to enhance lithiation in white Agaricus bisporus mushrooms: Li uptake and co-accumulation of other trace elements

Abstract

In an attempt to enrich the fruiting bodies with Lithium (Li), this study cultivated mushrooms using growing sets that were fortified with Li2O at 1.0, 5.0, 10, 50, 100 and 500 mg·kg−1 dw. Compost fortification up to 100 mg·kg−1 dw induced a dose-dependent increase in Li accumulation with resulting median mushroom concentrations of 2.0, 8.6, 16, 29 and 38 mg·kg−1 dw, respectively, relative to the unfortified control at 0.087 mg·kg−1 dw. The dose dependency appears to level off as Li2O addition approaches 100 mg·kg−1, suggesting that there is a limit to the ability of the species to accumulate/tolerate Li. Mushrooms did not grow at the 500 mg·kg−1 dw fortification level. At the highest viable level of fortification (100 mg·kg−1 dw), the fruiting bodies were around 440-fold richer in Li content than the control mushrooms. Additionally, the fortification at all levels up to 100 mg·kg−1 dw showed very low, if any, effect on the co-accumulation of the other, studied trace mineral constituents, with concentrations occurring at the lower range of those reported for commercial A. bisporus mushrooms.