Preparations derived from Lentinula edodes (Berk.) Pegl. mycelium are worldwide used as dietary supplements containing compounds active as immune system enhancers, demonstrating chemopreventive and anticancer activity. L. edodes mycelium enriched with organic forms of selenium like selenized yeast possess putative, higher cancer preventive properties. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water and alcohol extracts from mycelium of L. edodes (Berk.). To elucidate the cause of enhanced antioxidant activity of extracts, a preliminary selenium speciation by specific oxido-reduction reaction was performed
