title: Melanogenesis stimulation in murine B16 melanoma cells by Kava (Piper methysticum) rhizome extract and kavalactones.
abstract: Melanogenesis stimulation activity of aqueous ethanolic extracts obtained from several different parts of five Piper species, namely Piper longum, P. kadsura, P. methysticum, P. betle, and P. cubeba, were examined by using cultured murine B16 melanoma cells. Among them, the extract of P. methysticum rhizome (Kava) showed potent stimulatory effect on melanogenesis as well as P. nigrum leaf extract. Activity-guided fractionation of Kava extract led to the isolation of two active kavalactones, yangonin (2) and 7,8-epoxyyangonin (5), along with three inactive kavalactones, 5,6-dehydrokawain (1), (+)-kawain (3) and (+)-methysticin (4), and a glucosylsterol, daucosterin (6). 7,8-Epoxyyangonin (5) showed a significant stimulatory effect on melanogenesis in B16 melanoma cells. Yangonin (2) exhibited a weak melanogenesis stimulation activity.
authors.affiliation: School of Pharmaceutical Sciences, Kinki University, Higashiosaka, Osaka, Japan. matsuda@phar.kindai.ac.jp
authors.forename: Hideaki
authors.initials: H
authors.lastname: Matsuda
authors.forename: Noriko
authors.initials: N
authors.lastname: Hirata
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Naruto
authors.forename: Takanobu
authors.initials: T
authors.lastname: Takata
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Oyama
authors.forename: Munekazu
authors.initials: M
authors.lastname: Iinuma
authors.forename: Michinori
authors.initials: M
authors.lastname: Kubo
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D020901:Kava / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry / Q000494:pharmacology; D008543:Melanins / Q000096:biosynthesis*; D008546:Melanoma, Experimental / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology
chemical_list: D007783:Lactones; D008543:Melanins; D010936:Plant Extracts