This study aimed to investigate the anti-oxidative properties of the ethanolic extracts of the devil's club (Oplopanax horridus) leaves, stems, and roots. Furthermore, the anti-inflammatory activity of the leaf extract was analyzed. The leaf extract had higher total phenolic and flavonoid contents and anti-oxidative activity (radical scavenging, reducing power, and inhibition of lipid oxidation) than the root and stem extracts. The leaf extract also had anti-inflammatory effects. It significantly reduced lipopolysaccharide (LPS)-induced nitric oxide (NO; 71.0% at 50 μg/mL), tumor necrosis factor (TNF)-α (87.6% at 100 μg/mL), and interleukin (IL)-6 (36.2% at 100 μg/mL) production in murine RAW 264.7 macrophages. Furthermore, LPS-induced inducible nitric oxide synthase (iNOS) expression was decreased by the leaf extract (IC50=24.4 μg/mL). The ultra performance liquid chromatography-diode array detector (UPLC-DAD) analysis showed that the leaf extract contained gallic acid, protocatechuic acid, chlorogenic acid, and maltol. These findings suggest that the leaf extract could be utilized as a functional food material because of its anti-oxidative and anti-inflammatory activities.
Keywords: Oplopanax horridus; UPLC-DAD; anti-inflammatory activity; anti-oxidative activity; phenolic compounds.