Antioxidant Compounds of Sambucus pendula Stem

Sambucus pendula (Viburnaceae) is an Ulleung-do native plant belonging to the Sambucus species, widely known as “Jeob-Gol-Mok”. In this study, the antioxidant activity of S. pendula methanol extract and its fractions were observed. Seven compounds were isolated from the CH₂Cl₂ fraction, which showed the most potent antioxidant activity among the fractions, using silica gel and Sephadex LH-20 column chromatography, recrystallization, MPLC, and prep-HPLC. The chemical structures of the isolates were determined as (+)- isolariciresinol (1), (+)-cycloolivil (2), p-coumaryl alcohol (3), vanillin (4), ursolic acid (5), guaiacylglycerol (6), and ficusol (7) based on the spectroscopic data including¹H-NMR, ¹³C-NMR, DEPT, HMBC, and MS data. All isolated compounds were first reported as components of this plant. Among these compounds, (+)-isolariciresinol (1) and (+)-cycloolivil (2) showed potent antioxidant activities on DPPH and ABTS radical scavenging assays, and significant inhibitory activity on lipopolysaccharide-induced NO and ROS productions in RAW 264.7 cells. This is the first study to show the antioxidant activity related to the anti-inflammatory activity of S. pendula, and these results suggested that the methanol extract, CH₂Cl₂ fraction, and the isolated compounds could be developed as a new natural material for treating oxidative stress-related diseases.