Phytochemical Composition and Cytotoxic Activity of Senecio asirensis Hexane Fraction Using In Vitro and In Silico Approaches

Abstract

Objective: Senecio asirensis, an endemic species of Saudi Arabia, has been traditionally used to treat various ailments. The present study aimed to investigate the phytochemical composition, antimicrobial activity, and cytotoxic potential of Senecio asirensis fractions, and to identify the main compounds in the extract that are the most active. Methods: The antimicrobial activity was evaluated using disc diffusion assay. Moreover, the cytotoxic activity evaluated using the MTT assay in various cancer cell lines (MCF-7, HepG2, and A549) and validated by molecular docking for the major compound of the most active fraction. Finally, gas chromatography and a mass spectrometer (GC-MS) analysis was carried out to identify the chemical compounds in hexane extract of Senecio asirensis. Results: The hexane fraction exhibited significant antimicrobial activity against Gram-positive bacteria (S. aureus) and yeast organisms (C. albicans and C. tropicalis), while chloroform and butanol fractions showed no activity against the tested microbial strains. Moreover, in the cytotoxic activity assay, notably, the hexane fraction showed a significantly higher cytotoxic effect on MCF-7. The GC-MS analysis of the hexane fraction revealed the presence of 26 phytoconstituents, with nonacosane being the most abundant compound. Therefore, the molecular docking was employed to validate the cytotoxic activity for the major compound of the most active fraction (nonacosane) against human DNA topoisomerase IIa. Conclusion: These findings provide a scientific basis for the traditional use of S. asirensis in medicine and suggest that its bioactive compounds have potential therapeutic applications in anticancer treatments. Further research is needed to isolate and characterize other active compounds and to explore potential synergistic effects among them.