Evaluation of cytotoxicity of leaf and rhizome extracts of Alpinia calcarata rosc. against human lung nci-h460 and cervical hela cancer cell lines

The cytotoxicty of Alpinia calcarata rhizome and leaf extracts, fractions and essential oils were evaluated in vitro against human lung NCI-H460 and cervical HeLa cancer cell lines using sulphorhodamine-B assay. Although an array of bioactivities of A. calcarata rhizome have been reported previously, no attempt has been made to study the cytotoxicity of rhizome in human lung NCI-H460 and cervical HeLa cancer cell lines. In the present study, both the leaf and rhizome extracts (ethanolic and water) along with their fractions (hexane, dichloromethane, ethylacetate, butanol and water) and essential oils against human lung (NCI-H460) and human cervical (HeLa) cancer cell lines were investigated. Fresh rhizomes and leaves of Alpinia calcarata, collected from Western Province of Sri Lanka were used to obtain the extracts. The essential oils were obtained by hydro-distillation. All the samples were stored at 4 °C. The extracts, fractions and essential oils demonstrated a varying degree of growth inhibition against NCI-H460 cell line. Several fractions showed high growth inhibitory activity (4-94%). The growth inhibition order was, rhizome water extract (107.7%) < rhizome ethanolic extract (68.2%) < leaf ethanolic extract (-25.1%) < leaf water extract (-72.3%) < rhizome oil (-93.0%) < leaf oil (-94.3%). Dichloromethane fraction of leaf ethanolic extract (-33.8%) showed the most promising inhibition at GI50: 30.6 μg/mL on NCI-H460. For HeLa cells, the ethyl acetate (-0.5%), butanol (-5.0%) and aqueous fractions (-18.1%) of rhizome water extract showed high growth inhibitions. The potency of the growth inhibition was, rhizome ethanolic extract (76.56%) < rhizome water extract (16.65%) < leaf oil (15.88%) < rhizome oil (-49.34%). Efficacy and mechanisms of action in various normal and cancer cell models coupled with bioassay-guided purification to identify active anticancer compound(s) from the crude extract will be useful.