Anti-inflammatory diarylheptanoids and phenolics from the rhizomes of kencur (Kaempferia galanga L.)

Abstract Kencur ( Kaempferia galanga L.) is an aromatic plant of the Zingiberaceae family. It is widely cultured as a crops and its rhizome has been widely used as a flavor spice existing in various cooking. In this study, three new diarylheptanoids ( 1 – 3 ), one new phenolic glycoside ( 4 ), together with thirteen known phenolics were isolated from the rhizomes of kencur. Their chemical structures were elucidated based on IR, 1D and 2D NMR, HR-ESI-MS spectroscopic analysis and electronic circular dichroism (ECD) methods. Diarylheptanoids were evaluated for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in a macrophage RAW 264.7 cell line. Except for compound 7 , most of diarylheptanoids exhibited pronounced inhibitory activities compared with indomethacin. The results demonstrated that the diarylheptanoids may be partially responsible for the anti-inflammatory activity of kencur, which suggested that it could be served as an anti-inflammatory agent for healthy or medicinal products.