Suppression of Caco-2 and HEK-293 cell proliferation by Kigelia africana, Mimusops zeyheri and Ximenia caffra seed oils.

Animal-derived oils and purified fatty acids, but not indigenous fruit-tree-derived seed oils, have been used to study cell growth and differentiation. In this study, we determined the effects of the Kigelia africana, the Mimusops zeyheri and the Ximenia caffra seed-oil on cell proliferation in culture. Human colon adenocarcinoma (Caco-2) and human embryonic kidney (HEK-293) cells were maintained and treated with various concentrations (0, 20, 40, 80, 100 and 120 mg/l) of K. africana, M. zehyeri and X. caffra seed oil. The trypan blue dye exclusion method was used to determine cell growth 48-hours after oil treatment. All three tree seed oils suppressed both Caco-2 and HEK-293 cell growth in a dose-dependent manner. Importantly, the tree seed oils did not cause increased cell death as the number of dead cells remained unchanged under control and oil-treated conditions. K. africana oil significantly suppressed Caco-2 cell growth compared to HEK-293 cell growth at all oil concentrations, whereas M. zeyheri and X. caffra seed oils significantly suppressed HEK-293 and Caco-2 cell growth, only at a concentration of 80 mg/l. The suppression of Caco-2 and HEK-293 cell proliferation by K. africana, M. zeyheri and X. caffra seed oils suggest a potential antiproliferative effect of these tree seed oils on the two cell lines.