title: Suppression of the SOS-Inducing Activity of Trp-P-1 and Aflatoxin B1 by Meso-dihydroguaiaretic Acid from Machilus thunbergii in the Salmonella typhimurium TA1535/pSK1002 umu Test.
abstract: The methanol extract from Machilus thunbergii showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which requires liver metabolizing enzymes. The methanol extract from M. thunbergii was successively re-extracted with chloroform, butanol and water. A suppressive compound in the chloroform extract fraction was isolated by SiO2 column chromatography and identified as meso-dihydroguaiaretic acid by GC-MS, and (1)H- and (13)C-NMR spectroscopy. Meso-dihydroguaiaretic acid inhibited of the SOS-inducing activity of Trp-P-1 in the umu test. Gene expression was suppressed by 62% at less than 0.18 μmol/ml, the ID50 value being 0.08 μmol/ml. Compound 1 was also assayed with aflatoxin B1 (AfB1) and showed a suppressive effect.
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: M
authors.initials: M
authors.lastname: Miyazawa
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: Y
authors.initials: Y
authors.lastname: Okuno
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: K
authors.initials: K
authors.lastname: Oshiro
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: H
authors.initials: H
authors.lastname: Kasahara
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: H
authors.initials: H
authors.lastname: Shimamura
authors.affiliation: b Osaka Prefectural Institute of Public Health.
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: a Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University Kowakae.
authors.forename: H
authors.initials: H
authors.lastname: Kameoka
keywords: Lauraceae; Machilus thunbergii; SOS response; meso-dihydroguaiaretic acid; umu test