Three novel lupane-, bauerane-, and euphane-type triterpenoids (1-3), in addition to seven known triterpenoids (4-10)-18β,19β-epoxy-21β-hydroxylupan-3β-yl acetate (4), 21-oxolup-18-en-3β-yl acetate (5), betulin (6), officinatrione (7), 11α-methoxyolean-12-en-3-one (8), eupha-7,24-dien-3-one (9), and 24-oxoeupha-7,24-dien-3β-yl acetate (10)-were isolated from the roots of Taraxacum officinale. Their structures were elucidated on the basis of spectroscopic analyses using 1D and 2D-NMR spectra and electron ionization mass spectrometry (EIMS). The effects of compounds 1-10 on the production of nitric oxide (NO) in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages were evaluated. Compounds 4, 6, and 10 exhibited similar NO inhibitory activities to N(G)-monomethyl-l-arginine acetate (l-NMMA). These compounds did not exhibit cytotoxicity at an effective concentration. The results of present study suggest that compounds 4, 6, and 10 have potential as anti-inflammatory disease agents.
Keywords: 18β,19β-epoxy-21β-methoxylupan-3β-yl acetate; 3β-acetoxybauer-7-en-6-one; 3β-acetoxyeuph-7,24-dien-6-one; NO production; Taraxacum officinale; dandelion; triterpene.