title: Inhibitory effect of dalbergioidin isolated from the trunk of Lespedeza cyrtobotrya on melanin biosynthesis.
abstract: Tyrosinase is a key enzyme for melanin biosynthesis, and hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, which can be reduced by treatment with depigmenting agents. The methanol extract of Lespedeza cyrtobotrya MIQ showed inhibitory activity against mushroom tyrosinase. The active compound was purified from the methanol extract of L cyrtobotrya, followed by several chromatographic methods, and identified as dalbergioidin (DBG) by spectroscopic methods. The results showed that DBG exhibited tyrosinase inhibitory activity with an IC50 of 20 mM. The kinetic analysis tyrosinase inhibition revealed that DBG acted as noncompetitive inhibitor. In addition, DBG showed a melanin biosynthesis inhibition zone in the culture plate of Streptomyces bikiniensis that has commonly been used as an indicator organism. Furthermore, 27 mM DBG decreased more than 50% of melanin contents on the pigmentation using immortalized mouse melanocyte, melan-a cell.
authors.affiliation: Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Korea.
authors.forename: Seunghwa
authors.initials: S
authors.lastname: Baek
authors.forename: Jinhee
authors.initials: J
authors.lastname: Kim
authors.forename: Donghyun
authors.initials: D
authors.lastname: Kim
authors.forename: Chanyong
authors.initials: C
authors.lastname: Lee
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Kim
authors.forename: Dae Kyun
authors.initials: DK
authors.lastname: Chung
authors.forename: Choonghwan
authors.initials: C
authors.lastname: Lee
mesh_terms: D000363:Agaricales / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002867:Chromones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005656:Fungal Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D029884:Lespedeza / Q000737:chemistry / Q000378:metabolism*; D008543:Melanins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects / Q000502:physiology; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018547:Plant Stems / Q000737:chemistry / Q000378:metabolism*; D013302:Streptomyces / Q000187:drug effects / Q000378:metabolism
chemical_list: D002867:Chromones; D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D008543:Melanins; D010936:Plant Extracts; C531366:dalbergioidin; D014442:Monophenol Monooxygenase