Structural Characterization and Assessment of Anti-Inflammatory and Anti-Tyrosinase Activities of Polyphenols from .

Polyphenols, widely distributed in the genus plants, possess extensive cellular protective effects such as anti-inflammatory, anti-tyrosinase, and anti-obesity, which makes it a potential anti-inflammatory drug or enzyme inhibitor. Therefore, the aim of this study is to screen for the anti-inflammatory and enzyme inhibitory activities of compounds from title plant. Using silica gel, MCI, ODS C18, and Sephadex LH-20 column chromatography, as well as semipreparative HPLC, the extract of roots was separated. Four new ellagitannins, Whiskey tannin C (), 1--(4-methoxygalloyl)-6--galloyl-2,3--()-hexahydroxydiphenoyl--d-glucose (), 1--galloyl-6--(3-methoxygalloyl)-2,3--()-hexahydroxydiphenoyl--d-glucose (), and 1--galloyl-6--vanilloyl-2,3--()-hexahydroxydiphenoyl--d-glucose (), along with eight known polyphenols were firstly obtained from this plant. The structures of all isolates were elucidated by HRMS, NMR, and CD analyses. Using lipopolysaccharide (LPS)-stimulated RAW2 64.7 cells, we investigated the anti-inflammatory activities of compounds -, unfortunately, none of them exhibit inhibit nitric oxide (NO) production, their IC values are all > 50 μM. Anti-tyrosinase activity assays was done by tyrosinase inhibition activity screening model. Compound showed weak tyrosinase inhibitory activity with IC values of 426.02 ± 11.31 μM. Compounds - displayed moderate tyrosinase inhibitory activities with IC values in the range of 124.74 ± 3.12-241.41 ± 6.23 μM. The structure-activity relationships indicate that hydroxylation at C-3', C-4', and C-3 in the flavones were key to their anti-tyrosinase activities. The successful isolation and structure identification of ellagitannin provide materials for the screening of anti-inflammatory drugs and enzyme inhibitors, and also contribute to the development and utilization of .