Abstract

Ixora duffii is an important traditional medicinal plant in Vietnam. In this study its antioxidant property was investigated by diphenylpicrylhydrazyl (DPPH) radical and Fe3+ reducing assay and cytotoxic activity was evaluated against HepG2 cell line by MTT assay. The results showed that the methanolic extract of Ixora duffii flowers had DPPH radical scavenging activities similar to that of leaves extract. At the concentration of 100 ?g/mL, the extracts of flowers and leaves scavenged about 80% DPPH radical. The DPPH scavenging activity of Ixora duffii was lower than that of vitamin C approximately 2 times. The activity of Fe3+ reducing of flowers was higher than that of leaves, with EC50 values of 162.03 and 218.87 ?g/mL, respectively. Results were compared with the standard butylated hydroxyanisole (BHA) that was lower than 4.78 times in flowers and 6.76 times in leaves. The methanolic extract of Ixora duffii displayed significantly dose dependent in reducing the growth of HepG2, with 56% growth inhibitory concentration in a dose of 500 ?g/mL. The qualitative analysis of phytochemical compounds showed the presence of alkaloids, flavonoids, anthraquinones, terpenoids, quinones, glycoside, coumarins and phenols in the leaves and flower extracts of Ixora duffii. Compounds of tanins and saponins were only present in flowers of Ixora duffii. Total phenolic content were found in flowers (762.37 mg GAE/g) that was higher than the one in leaves (360.85 mg GAE/g). Flower and leave extracts exhibited a similar total flavonoid content of 679.55 mg QE/g and 676.35 mg QE/g, respectively.