Nitric oxide (NO) radical inhibitory of hedyotis philippinensis and its marker compound, asperuloside

Hedyotis spesies have been used in Chinese folk medicine as a treatment for colds, stomatitis and various inflammations. In this study, three methanolic extracts of Hedyotis species (Hedyotis corymbosa, Hedyotis havilandii and Hedyotis philippinensis) were screened for their anti-inflammatory activity. The plant extracts along with asperuloside, the marker compound of H. philippinensis were tested for their anti-inflammatory effect against lipopolysaccharide (LPS) and interferon- (IFN-)-induced nitric oxide (NO) production using RAW264.7 macrophage cells. Among the three species, H. philippinensis (leaves and stems) showed good NO radical inhibitory activity (with IC50 values of 139.76±12.50 and 176.21±2.48 g/ml, respectively). Asperuloside, isolated as a major compound from the plant moderately inhibited LPS/IFN--induced NO production by 63% at a concentration of 100 M (45% cell viability) compared to L-NAME (77 %). Its IC50 value was found to be 75.45±2.25 M. Its inhibition was also found to be dose-dependent.