The Anticancer Effects of Salvia palaestina Essential Oil Grown in Iraq

This preliminary in vitro study aimed to isolate the essential oil of Salvia palaestina and evaluate its cytotoxic activity against SKG-T4 and A2780 cancer cell lines.

The aerial parts of the plant were air dried, ground, and subjected to hydrodistillation using a Clevenger type apparatus for 3 hours. The obtained oil was dried over anhydrous sodium sulfate and stored at +4°C in the dark until use. GC/MS analysis was performed to identify the major phytochemical constituents. Cytotoxicity was assessed using a colorimetric MTT assay on esophageal SKG-T4 and ovarian A2780 cancer cell lines, with normal human fibroblasts (NHF) serving as the control. Cells were treated with serial concentrations of S. palaestina essential oil (100, 50, 25, 12.5, 6.25, 3.12 µl/ml) for 72 hours. Data were analyzed using GraphPad Prism software (version 8).

Treatment with the essential oil resulted in decreased cell viability in a concentration dependent manner. At 100µl/ml, cytotoxicity reached 62.8% in SKG-T4 cells and 52.3% in A2780 cells. The IC₅₀ values were 57.9µl/ml for SKG-T4 and 72.9µl/ml for A2780 cells, indicating notable anti cancer potential. The essential oil was slightly more potent in SKG-T4 cells and exhibited considerably lower cytotoxicity toward NHF cells, where 100µl/ml caused 27.2% cytotoxicity, with an IC₅₀ of 492.1µl/ml. The safety index (SI = IC₅₀₍non cancer₎ / IC₅₀₍cancer₎) was 8.5 for SKG-T4 and 6.8 for A2780, demonstrating greater selectivity toward cancer cells. Microscopic examination revealed morphological features of apoptosis, including cell shrinkage, membrane blebbing, and apoptotic body formation. GC/MS analysis showed limonene as the major constituent (73.05%), along with other phytochemicals with known anti cancer properties.

The essential oil of Salvia palaestina demonstrates promising anti cancer activity, characterized by concentration dependent cytotoxicity and a favorable safety index, supporting its potential as a selective anticancer agent.