title: Antioxidant activities of cultured Armillariella mellea.
abstract: This study aimed to evaluate the antioxidant activities of a cultured medicinal fungus--Armillariella mellea (Vahl. ex Fr.) Karst. (AM). Three antioxidant assay systems, namely cytochrome c, xanthine oxidase inhibition and FeCl2-ascorbic acid stimulated lipid peroxidation in rat tissue homogenate tests, were used. Total flavonoid and phenol contents of AM extracts were also analyzed. Results showed that both aqueous (AM-H2O) and ethanolic (AM-EtOH) extracts of solid state cultured AM showed antioxidant activities in a concentration-dependent manner. At concentrations 1-100 microg/ml, the free radical scavenging activity was 73.7-92.1% for AM-H2O, and 60.0-90.8% for AM-EtOH. These extracts also showed an inhibitory effect on xanthine oxidase activity, but with a lesser potency (IC50 - 9.17 microg/ml for AM-H2O and 7.48 microg/ml for AM-EtOH). In general, AM-H2O showed a stronger anti-lipid peroxidation activity on different rat's tissues than AM-EtOH. However, both AM extracts displayed a weak inhibitory effect on lipid peroxidation in plasma. Interestingly, the anti-lipid peroxidation activity of AM-H2O (IC50 - 6.66 microg/ml) in brain homogenate was as good as alpha-tocopherol (IC50 - 5.42 microg/ml). AM-H2O (80.0 mg/g) possessed a significant higher concentration of total flavonoids than AM-EtOH (30.0 mg/g), whereas no difference was noted in the total phenol content between these two extracts. These results conclude that AM extracts possess potent free radical scavenging and anti-lipid peroxidation activities, especially the AM-H20 in the brain homogenate.
authors.affiliation: Department of Biotechnology, Tajen University, Yanpu Shiang, Pingtung, Taiwan. lthuang@mail.tajen.edu.tw
authors.forename: L T
authors.initials: LT
authors.lastname: Ng
authors.forename: S J
authors.initials: SJ
authors.lastname: Wu
authors.forename: J Y
authors.initials: JY
authors.lastname: Tsai
authors.forename: M N
authors.initials: MN
authors.lastname: Lai
mesh_terms: D000363:Agaricales / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001921:Brain / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D005419:Flavonoids / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000378:metabolism; D066298:In Vitro Techniques; D015227:Lipid Peroxidation; D008099:Liver / Q000378:metabolism; D019800:Phenol / Q000378:metabolism*; D051381:Rats; D014020:Tissue Extracts; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D016166:Free Radical Scavengers; D014020:Tissue Extracts; D019800:Phenol; D045304:Cytochromes c; D014969:Xanthine Oxidase