title: Potent tyrosinase inhibitors from Trifolium balansae.
abstract: Trifolium balansae (Leguminosae) yielded a phytylester, phytyl-1-hexanoate, three steroids, stigmast-5-ene-3 beta,26-diol, stigmast-5-ene-3-ol and campesterol, and an alcohol, pentacosanol which were reported for the first time from T.balansae. The structures of the isolates were determined by 1D and 2D NMR techniques and MS spectroscopy. Compounds 1-5 were tested for their enzyme tyrosinase activity. While compounds 1 and 5 did not show any inhibition against the enzyme tyrosinase, compounds 2, 3, and 4 exhibited potent inhibition against tyrosinase. Highly potent (IC50 = 2.39 microM) inhibition was found by compound 2, when compared with the standard tyrosinase inhibitors Kojic acid and L-mimosine.
authors.affiliation: Science and Art Faculty, Department of Chemistry, Trakya University, Edirne, Turkey.
authors.forename: Temine
authors.initials: T
authors.lastname: Sabudak
authors.forename: Mahmut
authors.initials: M
authors.lastname: Tareq Hassan Khan
authors.forename: M
authors.initials: M
authors.lastname: Iqbal Choudhary
authors.forename: Sevil
authors.initials: S
authors.lastname: Oksuz
mesh_terms: D002784:Cholesterol / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010840:Phytosterols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013265:Stigmasterol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D029921:Trifolium / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D010840:Phytosterols; D010936:Plant Extracts; C021273:campesterol; D002784:Cholesterol; D013265:Stigmasterol; D014442:Monophenol Monooxygenase