Screening of antioxidant action of various molds and protection of Monascus anka against experimentally induced liver injuries of rats

Antioxidant action of various molds, which are traditionally used for the p roduction of foods or alcoholic beverages in Japan, was studied in vitro an d in vivo. Antioxidant action was evaluated by scavenging stable free radic al 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation of rat liver microsomes. Among 40 molds, 16 species showed the DPPH scavenging action, and the molds that can scavenge the DPPH radical inhibited lipid peroxidati on. The mold with the strongest action, Monascus anka, was chosen for the i nvestigation of a protective action against liver injury of rats. When gala ctosamine (GalN, 400 mg/kg) Or GalN plus lipopolysaccharide (LPS, 0.5 mu g/ kg) was given intraperitoneally to rats (Sprague-Dawley), aspartate aminotr ansferase (AST) and glutathione (GSH) S-transferase (GST) activities in ser um were significantly increased. However, such hepatotoxicities seen in the increase in serum enzyme levels were depressed when the extract prepared f rom M. anka was given 1 and 15 h before the toxic insultant. Liver microsom al GST activity, which is known to be activated by oxidative stress, was in creased by GalN or GalN plus LPS treatment and the increase was also inhibi ted by pretreatment with the extract. Pathomorphological changes in the liv er caused by GalN treatment also were prevented by the mold extract. These results indicate that the: extract of M. anka has radical scavenging action and ameliorates chemically induced hepatotoxicity. (C) 1999 Elsevier Scien ce Inc. All rights reserved.