Ethnobotanical Survey, Physiochemical Composition and Preliminary Cytotoxic Evaluation of some Medicinal Plants with Anticancer Potential from Certain Areas in South-West Nigeria

Aims: Medicinal plants used by traditional medical practitioners (TMP) to treat cancers are considered safe when used alone or combined with conventional therapy to ensure their effectiveness and eliminate the toxic effects of orthodox medicines. Using cytotoxic and antioxidant studies, the study attempted to assess some of the commonly used medicinal plants used to cure cancer among Yoruba people in Ogun, Oyo, Osun, and Lagos (South-West, Nigeria).

Study Design: Samples of commonly utilized anticancer plants obtained from the chosen areas using physical and virtual oral seminars were studied for physiochemical composition and a possible antioxidant and cytotoxic potential to validate the basis for the use of the selected anticancer plants.

Methodology: Online academic literature searches were done on the cited plants to identify the already-exploited anticancer plants. The ethanolic extracts of the plant were examined for the presence of bioactive components and their total flavonoid content, with focusing on quercetin detection using thin layer bioautography (TLB) and brine shrimp lethality assay (BSLA) for cytotoxicity. In comparison to quercetin and ascorbic acid, the scavenging of superoxide radical (SOR), hydrogen peroxide, and 2, 2-Diphenyl-2-picrylhydrazyl (DPPH) radical activity by a model (most biologically active) of the anticancer plant was also evaluated.

Results: There were only twelve anticancer species that were not used in related studies: Lannea egregia, Ficus exasperate, Croton zambesicus, Tetrapleurai tetraptera, Terminalia catappa, Zanthoxylum zanthoxyloides, Plumbago zelanica, Hilleria latifolia, Bryophyllum pinntum, Chromolena odorata, Brysocarpus coccineus and Spondias mombin. The anticancer plants contained bioactive and mineral substances like saponins, protein, lipids, magnesium, calcium, iron, zinc, and a decreased Na/K concentration. The plants had a fair amount of flavonoids and variable levels of cytotoxicity. L. egeregia was regarded as the prototype of the anticancer species due to its profound flavonoid concentration (85.40 µg/mL) and cytotoxicity (9.46 µg/mL) compared to other extracts. The TLB also demonstrated the presence of quercetin, with a dose-dependent antioxidant property. The anticancer model's overall antioxidant activity (34.72 µg/mL) was slightly lower than quercetin (30.44 µg/mL) but higher than ascorbic acid (41.68 µg/mL).

Conclusion: The results support the traditional use of anticancer species as nutritional and dietary supplements, whose bioactive compounds are relevant in managing cancer patients. The plant’s bioactive principles need to be characterized in future research.