title: Antimutagenicity of some edible Thai plants, and a bioactive carbazole alkaloid, mahanine, isolated from Micromelum minutum.
abstract: The antimutagenic activity against Trp-P-1 of methanolic extracts of 118 samples (108 species) of edible Thai plants was examined by the Ames Test. The activity was evaluated by the amount of plant extracts which suppressed 90% of the mutagenesis (ED90). Five plants, Micromelum minutum, Oroxylum indicum, Cuscuta chinensis, Azadirachta indica, and Litsea petiolata, exhibited significant activity with antimutagenic ED90 values lower than 5 microL/plate (0.1 mg of dry plant material equivalent). The activity-guided fractionation of the extract of M. minutum, which exhibited the highest antimutagenic activity in the screening, resulted in the isolation of an active principle, (+)-mahanine (1) as confirmed by its physicochemical properties. Compound 1 showed a wide variety of biological activity, including antimutagenicity against heterocyclic amines such as Trp-P-1 with an IC50 of 5.2 microM, cytotoxicity against a tumor cell line HL60 with a MIC100 of 4.0 microg/mL, and antimicrobial activity against Bacillus cereus and Staphylococcus aureus with MIC100 values of 6.25 and 12.5 microg/mL, respectively.
authors.affiliation: Japan International Research Center for Agricultural Sciences, 1-1 Owashi, Tsukuba, Ibaraki 305-8686, Japan. knakahar@jircas.affrc.go.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakahara
authors.forename: Gassinee
authors.initials: G
authors.lastname: Trakoontivakorn
authors.forename: Najeeb S
authors.initials: NS
authors.lastname: Alzoreky
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ono
authors.forename: Mayumi
authors.initials: M
authors.lastname: Onishi-Kameyama
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016587:Antimutagenic Agents / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology; D001409:Bacillus cereus / Q000187:drug effects / Q000254:growth & development; D029402:Bignoniaceae / Q000737:chemistry; D002227:Carbazoles / Q000302:isolation & purification / Q000494:pharmacology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D027722:Convolvulaceae / Q000737:chemistry; D019770:Lauraceae / Q000737:chemistry; D029582:Meliaceae / Q000737:chemistry; D009152:Mutagenicity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D027821:Rutaceae / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development; D013785:Thailand; D014407:Tumor Cells, Cultured
chemical_list: D000900:Anti-Bacterial Agents; D016587:Antimutagenic Agents; D000970:Antineoplastic Agents; D002227:Carbazoles; D010936:Plant Extracts; C465290:mahanine