title: Natural ortho-dihydroxyisoflavone derivatives from aged Korean fermented soybean paste as potent tyrosinase and melanin formation inhibitors.
abstract: Natural o-dihydroxyisoflavone (ODI) derivatives with variable hydroxyl substituent at the aromatic ring of isoflavone and three known isoflavones were isolated from five-year-old Korean fermented soybean paste (Doenjang) and evaluated as potent inhibitors on tyrosinase activity and melanin formation in melan-a cells comparing with other known isoflavones, 7,8,4'-trihydroxyisoflavone (1) and 7,3',4'-trihydroxyisoflavone (2) inhibited tyrosinase by 50% at a concentration of 11.21+/-0.8 microM and 5.23+/-0.6 microM (IC(50)), respectively, whereas, 6,7,4'-trihydroxyisoflavone (3), daidzein (4), glycitein (5) and genistein (6) showed very low inhibition activity. Furthermore, those compounds significantly suppressed the cellular melanin formation by 50% at a concentration of 12.23+/-0.7 microM (1), 7.83+/-0.7 microM (2), and 57.83+/-0.5(6) and show more activity than arbutin. But, compounds 3, 4, and 5 showed lower inhibition activity. This study shows that the position of hydroxyl substituent at the aromatic ring of isoflavone plays an important role in the intracellular regulation of melanin formation in cell-based assay system.
authors.affiliation: R&D Center, AmorePacific Corporation, Kyounggi-do, Republic of Korea. superbody@amorepacific.com
authors.forename: Jun-Seong
authors.initials: JS
authors.lastname: Park
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Kim
authors.forename: Jae Kyoung
authors.initials: JK
authors.lastname: Lee
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Duck Hee
authors.initials: DH
authors.lastname: Kim
authors.forename: Han Kon
authors.initials: HK
authors.lastname: Kim
authors.forename: Hak-Ju
authors.initials: HJ
authors.lastname: Lee
authors.forename: Ho Cheol
authors.initials: HC
authors.lastname: Kim
mesh_terms: D002460:Cell Line; D002478:Cells, Cultured; D005285:Fermentation / Q000502:physiology; D006801:Humans; D007529:Isoflavones / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D007723:Korea; D008543:Melanins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D045730:Soy Foods
chemical_list: D007529:Isoflavones; D008543:Melanins; D010936:Plant Extracts; D014442:Monophenol Monooxygenase