Pyrrolizidine alkaloids from Liparis nervosa with inhibitory activities against LPS-induced NO production in RAW264.7 macrophages

Six pyrrolizidine alkaloids and two others previously known were isolated from Liparis nervosa Thunb.Lindl. All of the compounds showed strong inhibitory activities against LPS-induced NO production in RAW 264.7 macrophages with IC50 values in the range of 2.16-38.25 μM.