title: Biological activity of alpha-thujaplicin, the isomer of hinokitiol.
abstract: alpha-Thujaplicin, a minor component of Aomori Hiba (Thujopsis dolabrata SIEB. et ZUCC. var. hondai MAKINO), showed rather strong antifungal activity against seven kinds of plant-pathogenic fungi, their minimum inhibitory concentrations (MICs) being in the range of 12.0-50.0 microg/ml. alpha-Thujaplicin and hinokitiol (the major component of Aomori Hiba) also showed clear antibacterial activity against Legionella pneumophila SG 1 and L. pneumophila SG 3, and their MICs are in the range of 6.25-50 microg/ml. This compound showed strong insecticidal activity against Reticulitermes speratus [50%-lethal concentration (LC(50)): 0.02 g/m(2)], and it also had clear acaricidal activity against Dermatophagoides farinae (LC(50): 0.66 g/m(2)). At 24 h after treatment, alpha-thujaplicin at 0.63 microg/ml inhibited the cell growth of murine P388 lymphocytic leukemia by 78%, and its cytotoxic activity at a concentration higher than 0.63 microg/ml was as high as that of vincristine, used as a positive control. On the other hand, the cytotoxic effect of alpha-thujaplicin at 0.63 microg/ml was weaker than that of vinblastine. In this respect, the strong cytotoxic effect of alpha-thujaplicin on murine P388 lymphocytic leukemia cell line should be emphasized, considering that it has recently been found to be low in toxicity to mice.
authors.affiliation: Osaka Organic Chemical Industry, Ltd., Kashiwara, Japan. yasuhiro_morita@ooc.co.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Morita
authors.forename: Eiko
authors.initials: E
authors.lastname: Matsumura
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Okabe
authors.forename: Toru
authors.initials: T
authors.lastname: Fukui
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Shibata
authors.forename: Masaaki
authors.initials: M
authors.lastname: Sugiura
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Ohe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsujibo
authors.forename: Nakao
authors.initials: N
authors.lastname: Ishida
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Inamori
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007941:Leukemia P388; D051379:Mice; D039821:Monoterpenes / Q000737:chemistry / Q000494:pharmacology*; D013237:Stereoisomerism; D014334:Tropolone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D039821:Monoterpenes; D014334:Tropolone; C009479:beta-thujaplicin