title: Chemical components and tyrosinase inhibitors from the twigs of Artocarpus heterophyllus.
abstract: An HPLC method was developed and validated to compare the chemical profiles and tyrosinase inhibitors in the woods, twigs, roots, and leaves of Artocarpus heterophyllus . Five active tyrosinase inhibitors including dihydromorin, steppogenin, norartocarpetin, artocarpanone, and artocarpesin were used as marker compounds in this HPLC method. It was discovered that the chemical profiles of A. heterophyllus twigs and woods are quite different. Systematic chromatographic methods were further applied to purify the chemicals in the twigs of A. heterophyllus. Four new phenolic compounds, including one isoprenylated 2-arylbenzofuran derivative, artoheterophyllin A (1), and three isoprenylated flavonoids, artoheterophyllin B (2), artoheterophyllin C (3), and artoheterophyllin D (4), together with 16 known compounds, were isolated from the ethanol extract of the twigs of A. heterophyllus. The structures of compounds 1-4 were elucidated by spectroscopic analysis. However, the four new compounds did not show significant inhibitory activities against mushroom tyrosinase compared to kojic acid. It was found that similar compounds, such as norartocarpetin and artocarpesin in the twigs and woods of A. heterophyllus, contributed to their tyrosinase inhibitory activity.
authors: School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China.
authors: Zong-Ping
authors: ZP
authors: Zheng
authors: Sibao
authors: S
authors: Chen
authors: Shiyun
authors: S
authors: Wang
authors: Xia-Chang
authors: XC
authors: Wang
authors: Ka-Wing
authors: KW
authors: Cheng
authors: Jia-Jun
authors: JJ
authors: Wu
authors: Dajiang
authors: D
authors: Yang
authors: Mingfu
authors: M
authors: Wang
mesh_terms: D000363:Agaricales / Q000201:enzymology; D031622:Artocarpus / Q000737:chemistry*; D005656:Fungal Proteins / Q000037:antagonists & inhibitors; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D010455:Peptides / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry
chemical_list: D005656:Fungal Proteins; D010455:Peptides; D010936:Plant Extracts; D014442:Monophenol Monooxygenase