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

Abstract

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 (CHCl 3 ) extract of the leaves inhibited the growth of cancer cells in vitro on HeLa cells (half maximal inhibitory concentration/IC 50 , 16,61mg/ml), and the cytotoxic compounds appeared present in the petroleum ether (PE) insoluble fraction (IC 50 , 3,078µg/ml) of the CHCl 3 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 (IC 50 , 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 (IC 50 = 9.776±0.77mg/ml) and WiDR cell lines (IC 50 , 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.