Phenylpropanoids from Lilium Asiatic hybrid flowers and their anti-inflammatory activities

Three phenylpropanoids were isolated from the flowers of Lilium Asiatic hybrids through repeated silica gel or octadecyl silica gel column chromatographies. The chemical structures were determined to be 1-O-trans-caffeoyl-β-d-glucopyranoside (1), regaloside A (2), and regaloside B (3), based on spectroscopic data gathered from nuclear magnetic resonance (NMR) spectroscopy, electron ionization mass spectrometry (EI/MS), polarimetry, and infrared spectroscopy (IR) experiments. Compounds 1 and 2 showed significant DPPH radical scavenging activity of 60.1 and 58.0% at 160 ppm, respectively, compared with the 62.0% activity of the positive control, α-tocopherol. At a concentration of 50 μg/mL, compounds 1–3 inhibited the expression of iNOS to 4.1 ± 0.01, 70.3 ± 4.07, and 26.2 ± 0.63, respectively, and decreasing COX-2 expression to 67.8 ± 4.86, 131.6 ± 8.19, and 98.9 ± 4.99. Also, at the same concentration, compounds 1–3 decreased the ratio of p-p65/p-65 to 43.8 ± 1.67, 40.7 ± 1.30, and 43.2 ± 1.60, respectively, and the expression of VCAM-1 to 42.1 ± 2.31, 48.6 ± 2.65, and 33.8 ± 1.74, respectively.