Metabolite Profiling and Cytotoxic Investigation of Senecio biafrae Oliv. & Hiern (Compositae) on Nauplii Brine Shrimps and Cancer Cell Lines

Background and Objective: Senecio biafrae possesses various therapeutic properties including hepatoprotective and antioxidant potentials. However, there is no information regarding its cytotoxic activity. Hence, this study investigated the cytoactivities of methanolic leaf extract (MLE) and fractions of Senecio biafrae, profiled and elucidated their metabolites. Materials and Methods: Hydromethanolic extract of S. biafrae obtained by maceration was partitioned and subjected to cytotoxicity screening using brine shrimp, human cervical adenocarcinoma (HeLa) and Prostate Cancer Cell (PC-3) lines. Bioactive principles of most of the active fractions were profiled using GC-MS. The dichloromethane (DCM) fraction was purified using column and High-Performance Liquid Chromatography (HPLC) to afford compounds 1 and 2 identified by ¹H and ¹³C, DEPT-90, DEPT-135, COSY, NOESY and EI-MS spectra. Results: The MLE and its fractions exhibited significant toxicity on nauplii brine shrimp, while the hexane fraction exhibited a pronounced cytoactivity on PC-3 cell line with 92.8% followed by DCM fraction. The GC-MS profiling of hexane and DCM fractions identified 17 and 6 constituents respectively, comprising saturated and unsaturated fatty acids, diterpenoidal alcohol, phytol and aromatic compounds. Hexadecanoic acid, cis, cis, cis-9, 12, 15-octadecatrienoic acid and phytol accounted for the highest constituents in both fractions. Structure elucidation confirmed compounds 1 and 2 as stigmasterol and ergosterol with cytoactivity which compared favourably with doxorubicin. Conclusion: The study revealed that S. biafrae contains cytoconstituents evidenced by proliferation inhibition of HeLa and PC-3 cell lines. The cytoactivities and bioconstituents indicate that S. biafrae has potential to be considered as a candidate for drug development that can manage cancer-related conditions. Further investigation into the specific bioactive compounds and their mechanisms of action could provide valuable insights into the therapeutic potential of S. biafrae in cancer treatment.