Synergistic Anticancer Effects of Flavonoid and Acetogenin Fractions from Annona muricata Leaves in Leukemic and Peripheral Blood Cells

Annona muricata (soursop) leaves are rich in bioactive compounds with known anticancer properties. Flavonoids and acetogenins, key constituents of these leaves, have shown potential antileukemic effects individually, but their combined efficacy and selectivity remain underexplored. The primary aim of the research is to examine the synergistic anticancer effects of flavonoid and acetogenin enriched fractions from A. muricata leaves on leukemic (Molt-3) cells and assess their cytotoxicity on normal peripheral blood lymphocytes (PBL). Ethanolic extracts of A. muricata leaves were subjected to bioassay-guided fractionation and chromatographic separation to isolate flavonoid and acetogenin enriched fractions. GC-MS was used to identify phytoconstituents. Cytotoxicity was assessed using MTT assay, and synergy was analysed using Combenefit software based on Loewe, Bliss, and Highest Single Agent models. Apoptosis and cell cycle changes were evaluated using flow cytometry. GC-MS analysis revealed the detection of flavonoids such as myricetin and luteolin glucosides, and acetogenins like muricatacin and α-muurolene. The combination of flavonoid and acetogenin fractions exhibited enhanced cytotoxicity in Molt-3 cells (IC₅₀: 40.21 μg/ml) compared to individual treatments. Synergy was confirmed across all models, particularly at 60 μg/ml of flavonoids and 80–100 μg/ml of acetogenins. Flow cytometry showed increased G0/G1 arrest and apoptosis in Molt-3 cells, while PBLs remained largely unaffected, indicating selectivity. Flavonoid and acetogenin fractions from A. muricata exert synergistic, selective cytotoxic effects on leukemic cells while sparing normal cells, suggesting their potential as a natural, targeted therapeutic approach for leukemia.