In vitro and in vivo anti-oxidant activity of hot water extract of basidiomycetes-X, newly identified edible fungus.

Basidiomycetes-X (BDM-X) is a novel edible mushroom recently identified as a new fungi species and registered to the database of the NPO organization for International Patent Organism Depositing (IPOD) in the Industrial Technology Institute of Japan (PCT/JP2004/006418). In the present study, we examined anti-oxidant activity of hot water extract of this novel fungus both in vitro and in vivo together with Agaricus Blazei Murill (ABM), a commercially available medicinal mushroom, and other reference antioxidants. As results, the hot water extract of BDM-X showed more potent anti-oxidative actions compared with that of ABM, when evaluated by 1,1'-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, Ferric Reducing Potential (FRP), and also the inhibition of 2,2'-azobis(2-amidino-propane) dihydrochloride (AAPH)-induced lipid peroxidation of rat liver homogenates. Further, the protective activity of BDM-X extract towards lipopolysaccharide (LPS)-induced hepatic oxidative damage was compared with ABM and alpha-lipoic acid in the mice pre-administered with these antioxidants. It was revealed that all of these antioxidants inhibited the LPS-induced oxidative tissue damage but the hot water extract of BDM-X showed the strongest protection among them. For example, the dose for 50% inhibition of carbonyl formation in liver was 0.53 g dry weight/kg body weight/d for BDM-X and the value corresponded to 16 mmol of alpha-lipoic acid as an antioxidant reference/kg body weight/d.