title: DPPH radical-scavenging compounds from dou-chi, a soybean fermented food.
abstract: Dou-chi, a traditional soybean food fermented with Aspergillus sp., is usually used as a seasoning in Chinese food, and has also been used as a folk medicine in China and Taiwan. As 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavengers, four phenol compounds, one isoflavanone, eight isoflavones and one 4-pyrone have been isolated from dou-chi. Among these fourteen compounds, 3'-hydroxydaidzein, dihydrodaidzein and a 4-pyrone compound have not yet been isolated from soybean miso. The structure of the novel 4-pyrone compound, 3-((E)-2-carboxyethenyl)-5-(4-hydroxyphenyl)-4-pyrone-2-carboxylic acid was elucidated by using the same compound as that obtained from the biotransformation of daidzein. 3'-Hydroxydaidzein showed as high DPPH radical-scavenging activity as that of alpha-tocopherol, and 6-hydroxydaidzein had mushroom tyrosinase inhibitory activity with an IC(50) value of 10 muM. The order of estrogenic activity is as follows: genistein > daidzein >> 3'-hydroxydaidzein > 8-hydroxygenistein, using a green fluorescent protein expression system. Furthermore, the contents of isoflavones in the fermentation process of dou-chi were measured.
authors.affiliation: School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Chen
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Sugiyama
authors.forename: Naoki
authors.initials: N
authors.lastname: Abe
authors.forename: Ryoko
authors.initials: R
authors.lastname: Kuruto-Niwa
authors.forename: Ryushi
authors.initials: R
authors.lastname: Nozawa
authors.forename: Akira
authors.initials: A
authors.lastname: Hirota
mesh_terms: D016587:Antimutagenic Agents / Q000494:pharmacology; D001713:Biphenyl Compounds; D001943:Breast Neoplasms / Q000378:metabolism; D045744:Cell Line, Tumor; D005285:Fermentation; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D008084:Lipoxygenase / Q000378:metabolism; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors; D048789:Phytoestrogens / Q000494:pharmacology; D010851:Picrates / Q000737:chemistry*; D045730:Soy Foods / Q000032:analysis
chemical_list: D016587:Antimutagenic Agents; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D007529:Isoflavones; D048789:Phytoestrogens; D010851:Picrates; C004931:1,1-diphenyl-2-picrylhydrazyl; D008084:Lipoxygenase; D014442:Monophenol Monooxygenase