Phytochemical Profiling of Tapinanthus globiferus for the Identification of Marker Compounds guiding its Ethnomedicinal and Anticancer Potential

Medicinal plants remain a valuable source of structurally diverse natural products with therapeutic potential. Tapinanthus globiferus (Loranthaceae) is widely used in African ethnomedicine, including for the treatment of cancer-related conditions, yet its chemical and pharmacological basis remains poorly defined. In this study, phytochemical profiling, cytotoxicity testing, and computational analyses were employed to characterize the bioactive potential of T. globiferus leaves. The butanol fraction demonstrated notable cytotoxic activity against HT-29 colon cancer cells, consistent with morphological evidence of apoptosis. High-performance liquid chromatography with diode array detection (HPLC–DAD) revealed the presence of abundant phenolic and flavonoid constituents, including kaempferol and quercetin derivatives, rutin, isoquercetin, catechin, and protocatechuic acid, which were identified as candidate marker compounds. To explore their therapeutic relevance, molecular docking was performed against angiogenic and apoptotic targets, particularly vascular endothelial growth factor A (VEGF-A) and the anti-apoptotic protein B-Cell Lymphoma 2 (BCL-2). To explore mechanisms, major identified compounds were docked in silico to VEGF-A and the anti-apoptotic protein BCL-2. Rutin, trifolin (a kaempferol glycoside), and epigallocatechin exhibited the strongest binding (e.g. rutin: –8.85 kcal/mol to VEGF-A), surpassing the reference inhibitor pazopanib (–3.56 kcal/mol) with multiple stabilizing interactions with these proteins, suggesting potential to interfere with tumor angiogenesis and cell survival pathways. Collectively, these findings provide a scientific basis for the traditional use of T. globiferus and support its fractions as promising sources of multi-targeted anticancer agents. The identification of marker compounds further establishes a foundation for bioassay-guided isolation, mechanistic validation, and future drug development.