Phytochemical analysis, antioxidant and cytotoxic activities of the Moroccan endemic species Stachys mouretii Batt. & Pit.

This study aims to investigate the phytochemical profile of S. mouretii leaf extracts obtained by sequential extraction techniques, “maceration/fractioning” and “Soxhlet”. Additionally, we evaluated their antioxidant activity using four assays: DPPH, FRAP, TAC, and ferrous ion (Fe2+) chelating activity. Furthermore, we examined the cytotoxic effect of the extracts in vitro against MDA-MB-468 (triple-negative human breast carcinoma) and P815 (murine mastocytoma) cancer cell lines using the MTT test. The results indicated that the extraction yield, phytochemical content, antioxidant, and cytotoxic activities varied with the solvent and the extraction method used. The highest yield was achieved with methanol extract (22.50%), and the lowest with n-hexane fractions (1.90%), using the maceration/fractioning method. Various bioactive compounds, including flavonoids, alkaloids, terpenes, tannins, and phenols, were detected. The fractionated extracts displayed superior cytotoxic activity compared to Soxhlet extracts. The n-hexane fraction demonstrated the greatest efficacy against the MDA-MB-468 (IC50 = 80.99 µg/mL) cancer cell line, while the ethyl acetate fraction showed remarkable effects on the P815 (IC50 = 15.07 µg/mL) cancer cell line. Furthermore, the methanolic extract (Soxhlet) possessed the highest antioxidant activity. Importantly, all S. mouretii extracts appeared non-toxic towards normal cells (PBMC).