title: β-carboline derivatives and diphenols from soy sauce are in vitro quinone reductase (QR) inducers.
abstract: A murine hepatoma (Hepa 1c1c7) cellular bioassay was used to guide the isolation of phase II enzyme inducers from fermented soy sauce, using quinone reductase (QR) as a biomarker. A crude ethyl acetate extract, accounting for 8.7% of nonsalt soluble solids of soy sauce, was found to double relative QR specific activity at 25 μg/mL (concentration required to double was defined as a "CD value"). Further silica gel column fractionation yielded 17 fractions, 16 of which exhibited CD values for QR induction of <100 μg/mL. The four most potent fractions were subfractionated by column and preparative thin layer chromatography, leading to the isolation and identification of two phenolic compounds (catechol and daidzein) and two β-carbolines (flazin and perlolyrin), with respective CD values of 8, 35, 42, and 2 μM. Western blots confirmed that the increases in QR activity corresponded to dose-dependent increases in cellular levels of NAD[P]H:quinone oxidoreductase 1 protein by these four QR inducers. To the authors' knowledge, this is the first report on the ability of β-carboline-derived alkaloids to induce phase II enzymes.
authors.affiliation: Department of Food Science, Babcock Hall, University of Wisconsin-Madison, 1605 Linden Drive, Madison, Wisconsin 53706, United States.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
authors.forename: Kirk L
authors.initials: KL
authors.lastname: Parkin
mesh_terms: D000818:Animals; D002243:Carbolines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D045744:Cell Line, Tumor; D004789:Enzyme Activation / Q000187:drug effects; D051379:Mice; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism*; D019800:Phenol / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D045730:Soy Foods / Q000032:analysis*
chemical_list: D002243:Carbolines; D010936:Plant Extracts; D019800:Phenol; D016660:NAD(P)H Dehydrogenase (Quinone)