ISOLATION AND IDENTIFICATION OF POTENTIAL CYTOTOXIC COMPOUND FROM KEMBANG BULAN [TITHONIA DIVERSIFOLIA (HEMSLEY) A GRAY] LEAVES

Objective: The leaves of Kembang Bulan [Tithonia diversifolia (Hemsley) A. Gray] are used traditionally to treat various deseases in Indonesia. Initial study showed that chloroform (CHCl3) extract of the leaves inhibited the growth of cancer cells in vitro on HeLa cells (half maximal inhibitory concentration/IC50, 16,61mg/ml), and the cytotoxic compounds appeared present in the petroleum ether (PE) insoluble fraction (IC50, 3,078µg/ml) of the CHCl3 extract. Objective of the present study was to screen cytotoxic activity of its further fractions and isolates.Methods: The PE insoluble fraction was fractionated by vacuum column chromatography to give 5 combined fractions (I-V). Fraction III, containing 3 isolates (A, B, and C) on thin-layer chromatrography (TLC) displays highest cytotoxic activity that is then subjected into preparative TLC.Results: According to cytotoxic bioassay, B isolate was the active one (IC50, 47.074±4.79 ug/ml), and further purification of B isolate results in 3 isolates (B1, B2 and B3). B2 isolate was tested on several human cancer cell lines, and shows the most cytotoxic in vitro on HeLa (IC50= 9.776±0.77mg/ml) and WiDR cell lines (IC50, 0.585±0,08 ug/ml).Conclusion: B2 isolate was a major cytotoxic compound and identified as Tagitinin C, based on its spectroscopic data and comparison with the previous reported, data