Abstract
Based on the traditional use of the calyx of eggplants for treatment of common warts and a clinical report that the ethanol extract of the calyx of the eggplant is effective for curing genital warts, the cytotoxicity of the ethanol extract of the eggplant against various cell lines established from human cancer cells was examined. The extract of eggplants inhibited cell growth of human ovary cancer (HRA) cells, which are of epithelial cell origin similar to common warts. The cytotoxicity of the extract from the calyx of the eggplants is much higher than that of the extract from the edible part of the eggplants. Two compounds, 9-oxo-(10E, 12Z)-octadecadienoic acid (9-EZ-KODE) and 9-oxo-(10E, 12E) octadecadienoic acid (9-EE-KODE) were isolated as cytotoxic constituents from the calyx of the eggplants. 9-EE-KODE exhibited approximately 10-fold higher cytotoxicity than 9-EZ-KODE. Furthermore, 9-EE-KODE revealed 5-fold more potent cytotoxicity against HRA cells than against other cell lines examined. The calyx contained higher levels of 9-EE-KODE than the edible part of the eggplants.
