Apoptosis-inducing activity of an abietane diterpenoid-rich fraction from Salvia oligophylla roots against MCF-7 cancer cells

Salvia oligophylla Aucher ex Benth., an endemic Iranian species, remains largely unexplored with respect to its phytochemical composition and biological activities. Based on TLC profiling and the reported occurrence of abietane diterpenoids in the roots of Salvia species, the n -hexane extract was selected for further fractionation by column chromatography, yielding fourteen fractions. The cytotoxic potential of these fractions against MCF-7 breast cancer cells was evaluated using the MTT assay, and apoptosis induction was assessed by flow cytometry. Among the fractions, F3 exhibited the highest cytotoxic activity. Flow cytometry demonstrated a marked increase in both early and late apoptotic cell populations with minimal necrosis, indicating that apoptosis is the predominant mechanism of cell death. HPLC-DAD localized the major bioactive zone within the n -hexane extract. LC-QTOF-HRMS-based dereplication, supported by experimental MS/MS fragmentation and UV spectral comparison, indicated that the major constituent is a quinoid abietane diterpenoid, with Salviskinone A representing the best-matching candidate. These findings highlight roots of S. oligophylla as a promising source of apoptosis-inducing diterpenoids and provide a strong basis for future isolation, structural characterization, and mechanistic investigations of the bioactive constituents.