title: Proanthocyanidins Extracted from Rhododendron pulchrum Leaves as Source of Tyrosinase Inhibitors: Structure, Activity, and Mechanism.
abstract: The objective of this study was to assess the structure, anti-tyrosinase activity, and mechanism of proanthocyanidins extracted from Rhododendron pulchrum leaves. Results obtained from mass spectra of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) revealed that proanthocyanidins were complex mixtures of procyanidins, prodelphinidins, propelargonidins, and their derivatives, among which procyanidins were the main components. The anti-tyrosinase analysis results indicated that the mixtures were reversible and mixed competitive inhibitors of tyrosinase. Interactions between proanthocyanidins with substrate (L-tyrosine and 3,4-dihydroxyphenylalanine) and with copper ions were the important molecular mechanisms for explaining their efficient inhibition. This research would provide scientific evidence for the use of R. pulchrum leaf proanthocyanidins as new novel tyrosinase inhibitors.
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.|Key Laboratory of Poyang Lake Wetland and Watershed Research, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Wei-Ming
authors.initials: WM
authors.lastname: Chai
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Man-Kun
authors.initials: MK
authors.lastname: Wei
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Zheng-Rong
authors.initials: ZR
authors.lastname: Zou
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Rong-Gen
authors.initials: RG
authors.lastname: Deng
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Wei-Sheng
authors.initials: WS
authors.lastname: Liu
authors.affiliation: College of Life Science and Key Laboratory of Small Functional Organic Molecule, Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, People's Republic of China.
authors.forename: Yi-Yuan
authors.initials: YY
authors.lastname: Peng
mesh_terms: D000363:Agaricales / Q000201:enzymology; D003300:Copper / Q000494:pharmacology; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D062105:Molecular Docking Simulation; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry*; D044945:Proanthocyanidins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D029793:Rhododendron / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D044945:Proanthocyanidins; D003300:Copper; D014442:Monophenol Monooxygenase