Comparative study of phytochemistry, in vitro antioxidant and molluscicidal potentials of different extracts of Ficus exasperata stem bark

Schistosomiasis, a neglected tropical disease, remains a significant global health concern. While vector control strategies often rely on the use of synthetic molluscicides (such as Niclosamide) which has also been attributed to environmental and health concern with its nonspecific action. This has brought about a growing interest in exploring natural alternatives with reduced environmental impact. This study investigated the potential of Ficus exasperata stem bark extracts as a natural molluscicide against Bulinus snails, the intermediate host for Schistosoma haematobium. The stem bark was extracted using various solvents (ethanol, methanol and water), and the resulting extracts were subjected to phytochemical analysis, in vitro antioxidant assays, and molluscicidal activity testing. The phytochemical analysis revealed the presence of compounds like phenolics, tannins, cardiac glycosides, flavonoids, saponins and some trace number of steroids and alkaloids, which are known for their diverse biological activities. In vitro antioxidant assays demonstrated moderate properties with the highest percentage inhibition (DPPH) of 62, 60 and 47%, for methanolic, aqueous and ethanolic extracts respectively. However, the molluscicidal activity assays revealed significant toxicity against Bulinus snails. Particularly with the ethanolic extract, which exhibited the lowest LC50 (23.59 ppm) value while methanolic and aqueous extracts have LC50 value of 28.96 ppm and 31.51 ppm, respectively. These findings suggest that F. exasperata stem back extracts could serve as a promising natural source of molluscicidal compounds, offering a sustainable and eco-friendly approach to schistosomiasis control. Further research is needed to optimize extraction methods, identify the specific bioactive compounds responsible for molluscicidal activity, and evaluate their safety and efficacy in field trials.