Mycosensing of soil contaminants by Ganoderma lucidum and Omphalotus subilludens including the insights on growth media requirements

Abstract

Heavy metals are regarded as one of the major threats to environmental biota due to prolonged soil residence time. In this scenario, mycoremediation emerged as an effective tool for the removal of heavy metal contaminants. The present study reports the responses of two wild mushroom species Ganoderma lucidum and Omphalotus subilludens under metal stress conditions and the nutritional requirements of the mushroom species. The media was screened wherein the media containing glucose and sucrose as carbon source showed better growth for Ganoderma lucidum and Omphalotus subilludens respectively. In addition, peptone as a nitrogen source is required for the growth of both Ganoderma lucidum and Omphalotus subilludens. Further, it is observed that macronutrients play a crucial role in the stimulation of enzymes and the micronutrients are mandatory for intermediary metabolism of the fungi in both the species. Tolerance studies are carried out in-vitro and the results reveal that the Ganoderma lucidum showed tolerance towards Cr (VI), Ni (II), Pb (II) and Cd (II) at maximum tolerant concentrations of 1000 mg/kg, 500 mg/kg, 100 mg/kg and 10 mg/kg, in case of, Omphalotus subilludens showed tolerance towards Cr (VI), Ni (II) and Pb (II) at maximum tolerant concentration of 700 mg/kg, 700 mg/kg and 500 mg/kg respectively. Moreover, FTIR spectral analysis indicated the presence of components like oxalic acid and thiol compounds during metal stress conditions. 2019 Elsevier Ltd