Volatile constituents and in vitro activity of Syzygium aromaticum flower buds (clove) against human cancer cell lines

The methanolic extract (SA-EXT) of Syzygium aromaticum flower buds and its fractions tested against three human cancer cell lines viz uterine cervix (HeLa), breast (MCF-7) and lung NCI (H-460) using sulforhodamine-B assay. The ethyl acetate soluble sub fraction (SA-EAS) was active only against HeLa cells with GI 50 value of 36 +/- 3.4 mu g/mL. The most active sub-fraction (SA-PES-Fr-2) showed growth inhibition (GI(50): 36, 50 and 68 mu g/ml against MCF -7, HeLa and NCI-H-460 cancer cell lines, respectively) with cytotoxic effect LC50 = 88 +/- 3.4 mu g/mL against HeLa and LC50 =86 +/- 2.8 mu g/mL against MCF-7. The most active sub-fraction (SA-PES-Fr-2) analyzed by GC and GC-MS techniques revealed that eugenol was most abundant (85.34%) along with minor constituents. Thus it can be concluded that growth inhibitory and cytotoxic effect residing in Syzygium aromaticum flower buds (clove) is more likely due to eugenol.