Selenium distribution in a Se-enriched mushroom species of the genus Ganoderma.

Data reported here show that Ganoderma lucidum could biotransform inorganic selenite in the substrate into organic forms by intergrating Se into proteins (56-61%) and polysaccharides (11-18%) and other components. Furthermore, water- and alkaline-soluble protein components were mainly responsible for the storage of organic Se, and Se-Met accounts for only a minor (8.2-18.3%) amount of the selenocompounds present in proteins. The molecular mass of most proteins or protein subunits containing Se was no more than 16 kDa. A low concentration of Se (<100 microg/g) in the substrate facilitated the synthesis of total protein and amino acids in G. lucidum, but a high concentration of Se (>150 microg/g) played a reverse role. Additionally, Se concentration in the culture had no significant effect on the distribution of the amino acids and proteins.