Flavonols from Heterotheca inuloides : Tyrosinase Inhibitory Activity and Structural Criteria
| Autor: | Yumi Kubo, Yolanda Sanchez, Swapan K. Chaudhuri, Tetsuya Ogura, Isao Kubo, Ikuyo Kinst-Hori |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Flavonols
Stereochemistry Tyrosinase Clinical Biochemistry Pharmaceutical Science Biochemistry Flavones Arnica Fungal Proteins Levodopa Inhibitory Concentration 50 Structure-Activity Relationship chemistry.chemical_compound Drug Discovery Chrysin Enzyme Inhibitors Kaempferols Catechol oxidase Molecular Biology Chelating Agents Flavonoids chemistry.chemical_classification Binding Sites Plants Medicinal biology Monophenol Monooxygenase Plant Extracts Chemistry Organic Chemistry Enzyme assay Galangin Kinetics Spectrophotometry Flavanones biology.protein Molecular Medicine Quercetin Kaempferol Oxidation-Reduction Catechol Oxidase Copper |
| Zdroj: | Bioorganic & Medicinal Chemistry. 8:1749-1755 |
| ISSN: | 0968-0896 |
| Popis: | Tyrosinase inhibitory activity of flavonols, galangin, kaempferol and quercetin, was found to come from their ability to chelate copper in the enzyme. In contrast, the corresponding flavones, chrysin. apigenin and luteolin, did not chelate copper in the enzyme. The chelation mechanism seems to be specific to flavonols as long as the 3-hydroxyl group is free. Interestingly, flavonols affect the enzyme activity in different ways. For example, quercetin behaves as a cofactor and does not inhibit monophenolase activity. On the other hand, galangin inhibits monophenolase activity and does not act as a cofactor. Kaempferol neither acts as a cofactor nor inhibits monophenolase activity. However, these three flavonols are common to inhibit diphenolase activity by chelating copper in the enzyme. |
| Databáze: | OpenAIRE |
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