Background: Breast cancer is one of the most frequently diagnosed malignancies among women worldwide, necessitating the exploration of novel therapeutic agents derived from natural products. Medicinal plants containing bioactive phytochemicals have gained considerable interest due to their antioxidant and anticancer properties. This study aimed to investigate the phytochemical profile, antioxidant activity, and cytotoxic potential of the ethanol leaf extract of Heliotropium marifolium.

Methods: Qualitative phytochemical screening was performed to identify major secondary metabolites in the plant extract. Antioxidant activity was evaluated using the DPPH free radical Scavenging assay. The cytotoxic effect of the extract was determined using the MTT cell viability assay against MCF-7. Morphological alterations in treated cells were examined by microscopic observation to assess apoptotic features.

Results: Phytochemical analysis confirmed the presence of several biologically active constituents, including alkaloids, flavonoids, tannins, saponins, and terpenoids. The extract demonstrated significant free radical scavenging activity in the DPPH assay, indicating strong antioxidant potential. In vitro cytotoxicity assessment revealed a concentration-dependent inhibition of cancer cell proliferation, with an IC₅₀ value of 147.8 ± 2.14 µg/mL. Treated cells exhibited characteristic apoptotic morphological changes, including cellular shrinkage, membrane blebbing, and detachment from the culture surface. The reference anticancer agent Doxorubicin showed greater cytotoxic potency with a lower IC₅₀ value.

Conclusion: The findings demonstrate that Heliotropium marifolium possesses notable antioxidant capacity and moderate antiproliferative activity against breast cancer cells. The observed biological effects may be attributed to the presence of phenolic and flavonoid compounds in the extract. These results highlight the potential of this plant as a promising source of bioactive molecules for the development of novel anticancer therapeutics. Further studies focusing on isolation of active constituents and elucidation of molecular mechanisms are warranted.