Three Ballota species, Ballota undulata, Ballota saxatilis and Ballota nigra ssp. foetida, were investigated for their cytotoxicity against two human cancer cells, hepatoma HepG2 cell line and breast cancer MCF-7 cell line, and for their antioxidant activity. The chemical composition of essential oils was studied by GC and GC-MS. Sesquiterpenes were the main constituents. The most antiproliferative essential oil against HepG2 cells was B. undulata with a percentage of inhibition of 81.36 ± 3.54 at a concentration of 100 μg/mL, while against MCF-7 cells essential oil from B. saxatilis was the most active with a percentage of inhibition of 24.18 ± 1.13 at a concentration of 100 μg/mL. The antioxidant activity was investigated by DPPH test for all the oils. B. undulata showed the highest antiradical effect, with IC50 value of 529.7 ± 37.4 μg/mL.
Keywords: Ballota species; antiproliferative activity; breast cancer; essential oil; hepatoma; sesquiterpenes.