Anti-Inflammatory Phenolic Acid Esters from the Roots and Rhizomes of Notopterygium incisium and Their Permeability in the Human Caco-2 Monolayer Cell Model.

A new ferulic acid ester named 4-methyl-3--hexenylferulate (), together with eight known phenolic acid esters (-), was isolated from the methanolic extract of the roots and rhizomes of . Their structures were elucidated by extensive spectroscopic techniques, including 2D NMR spectroscopy and mass spectrometry. 4-Methoxyphenethyl ferulate () NMR data is reported here for the first time. The uptake and transepithelial transport of the isolated compounds - were investigated in the human intestinal Caco-2 cell monolayer model. Compounds and were assigned for the well-absorbed compounds, compound was assigned for the moderately absorbed compound, and compounds , , , , , and were assigned for the poorly absorbed compounds. Moreover, all of the isolated compounds were assayed for the inhibitory effects against nitric oxide (NO) production in the lipopolysaccharide-activated RAW264.7 macrophages model and ⁶-(1-iminoethyl)-lysine (L-NIL) was used as a positive control. Compounds , , , and exhibited potent inhibitory activity on NO production with the half maximal inhibitory concentration (IC) values of 1.01, 4.63, 2.47, and 2.73 μM, respectively, which were more effective than L-NIL with IC values of 9.37 μM. These findings not only enriched the types of anti-inflammatory compounds in but also provided some useful information for predicting their oral bioavailability and their suitability as drug leads or promising anti-inflammatory agents.