A new phenol derivative, hostaphenol A (1), along with 16 known ones (2-17) were isolated from an ethanolic extract of the whole plants of Hosta ensata F. Maek. Their structures were elucidated by HRMS and NMR data as well as comparison with those reported in literature. The report of the first cyclopeptide and compounds 5, 6, 8, 10, 12-15, and 17 in the Asparagaceae family. Compound 2, as well as compounds 3, 4, 7, 9, 11, and 16 were reported for the first time from the Hosta genus and this plant, respectively. All compounds significantly reduced nitric oxide (NO) production at a concentration of 40 μM with no toxicity in RAW 264.7 cells stimulated by lipopolysaccharide. Among them, compounds 2-5 (40 μM) exerted obvious NO inhibitory activities, and their inhibition rate was exceeded 50%.
Keywords: Hosta ensata; anti-inflammatory activity; hostaphenol A; phenol derivative.