Chemical composition and in vitro cytotoxic activity of the essential oils of Stachys rupestris and Salvia heldreichiana, two endemic plants of Turkey.

The chemical composition of the essential oils of two endemic plants of Turkey, Stachys rupestris Montbret et Aucher ex Benth. and Salvia heldreichiana Boiss. ex Benth., were obtained by hydrodistillation and studied by GC and GC-MS. In all, 46 compounds were identified, 22 for S. rupestris accounting for 94.6% of the total oil and 30 for S. heldreichiana, accounting for 91.9% of the total oil. The presence of diterpenoids (50.7%) characterized the oil from S. rupestris, while S. heldreichiana oil was rich in oxygenated sesquiterpenes (78.9%).The essential oils were evaluated for their in vitro potential cytotoxic activity on three human cancer cell lines. The oil of S. rupestris showed the higher antiproliferative activity against PC-3 and MCF-7 cancer cell lines.