Cytotoxic, apoptotic and antioxidant activity of the essential oil of Amomum tsao-ko

The antioxidant activity, cytotoxicity and mechanism of induction of HepG2 cell death of essential oil from Amomum tsao-ko were determined. The essential oil was cytotoxic to HepG2, Hela, Bel-7402, SGC-7901 and PC-3 cell lines. The lowest IC50 of 31.80 ± 1.18 μg/ml was measured for HepG2 carcinoma cell lines. The IC50 for normal human cell lines (HUVEC and HL-7702) was 163.91 ± 5.11–272.41 ± 0.97 μg/ml. Analyses by flow cytometry, Hoechst 33258 staining and agarose gel electrophoresis indicated that the essential oil induced apoptosis. The essential oil has weak antioxidant activity as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, thiobarbituric acid (TBA) test and ferric reducing antioxidant power (FRAP) assay. The data suggest that the essential oil of A. tsao-ko could be a potential medicinal resource.