Genoprotective capacity of alternatively cultivated lingzhi or reishi medicinal mushroom, ganoderma lucidum (agaricomycetes), basidiocarps

Abstract

Ganoderma lucidum is traditionally used in Eastern medicine to preserve vitality, promote longevity, and treat disease. It possesses immunomodulatory, antitumor, antimicrobial, and antiaging activities, among others, but one of the most important is its antioxidant property, which is the basis for other effects, because free radicals trigger many diseases. The substrate commonly used for commercial cultivation of G. lucidum is not environmentally friendly nor economically justified, so there is a need to find new alternative substrates. The aim of this study was to analyze the effect of substrate composition on the bioactivity of G. lucidum basidiocarps. G. lucidum was cultivated on 2 different substrates: (1) a mixture of wheat straw, grapevine branches, and wheat bran, and (2) wheat straw. Commercial fruiting bodies, cultivated on oak sawdust, were used as the control. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, total phenols, and flavonoid content were determined spectrophotometrically to define the antioxidative potential of basidiocarp extracts. The comet test was performed to detect the degree of DNA damage in the cells that were exposed to G. lucidum extracts before and after the effect of oxidants. Higher antioxida-tive potential was observed for the extract of G. lucidum basidiocarps cultivated on wheat straw compared with that from the mixed substrate and especially with commercial ones. The alternatively cultivated basidiocarps also showed stronger antigenotoxic potential compared with commercial ones. The study showed that fruiting bodies produced on wheat straw, one of the most accessible and cheapest crop residues, are more potent antioxidant and antigenotoxic agents than commercially cultivated ones.