Thesis (M.Sc.)--Chulalongkorn University, 2012

This research focused on the isolation and identification of anti-inflammatory compounds from Harrisonia perforata. Chromatographic fractionation of the EtOAc crude extracts of H. perforata fruits and roots led to the isolation of two new rearranged limonoids, harperfolide (2) and harperforatin (4), and a new chromone, harperamone (8), together with six known compounds including harrisonin (1), obacunone (3), (+)-vouacapenic acid (5), harrisonol A (6), peucenin-7-methyl ether (7) and braylin I (9). Among known compounds, a coumarin braylin I (9) and a cassane diterpene (+)-vouacapenic acid (5) were first isolated from the genus Harrisonia. The structures of new compounds were elucidated on the basis of spectroscopic data and single-crystal X-ray diffraction analysis, whereas those of the known ones were identified by comparison of their spectroscopic data with those in the literature. Isolated compounds were assessed for their anti-inflammatory activity by monitoring the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced macrophage J774.A1 cell lines. Harperfolide (2), a new rearranged limonoid, displayed the most potent anti-inflammatory activity by suppressing nitric oxide production from activated macrophages with IC50 value of 6.51 M. Furthermore, the inhibitory effect of harperfolide (2) on NO production via the inhibition of the corresponding iNOS protein expression, was further investigated by Western blot analysis. Pretreatment of the cells with various concentrations of 2 attenuated LPS-induced iNOS protein expression in a concentration-dependent manners. These data suggested harperfolide (2) can down regulate LPS-induced iNOS expression at the transcriptional level.