Zong-Ping Zheng, Ka-Wing Cheng, J. Chao
Jan 15, 2008
Citations
1
Influential Citations
133
Citations
Quality indicators
Journal
Food Chemistry
Abstract
Abstract Fractionation of a chloroform-soluble extract from twigs of Broussonetia papyrifera , led to the isolation of one new compound, 3,5,7,4′-tetrahydroxy-3′-(2-hydroxy-3-methylbut-3-enyl)flavone ( 1 ), and 10 known compounds, uralenol ( 2 ), quercetin ( 3 ), isolicoflavonol ( 4 ), papyriflavonol A ( 5 ), broussoflavonol F ( 6 ), 5,7,3′,5′-tetrahydroxyflavanone ( 7 ), luteolin ( 8 ), isoliquiritigenin ( 9 ), broussochalcone A ( 10 ) and 5,7,3′,4′-tetrahydroxy-3-methoxyflavone ( 11 ). Their structures were identified by interpretation of MS, 1 H NMR, 13 C NMR, HMQC and HMBC data. Their inhibitory activities on mushroom tyrosinase using l -tyrosine as substrate were investigated and the IC 50 values of 3,5,7,4′-tetrahydroxy-3′-(2-hydroxy-3-methylbut-3-enyl)flavone, uralenol, quercetin and broussoflavonol F were found to be 96.6, 49.5, 57.8, and 82.3 μM, respectively, better than arbutin, a well-known tyrosinase inhibitor.