In vitro and in silico schistosomicidal activity of hexane fraction from Copaifera oblongifolia leaves

Neglected tropical diseases (NTDs) are prevalent in developing countries, leading to significant morbidity and mortality. Despite affecting millions, these diseases receive limited attention from pharmaceutical companies due to their low profitability, resulting in minimal research on novel therapies. Schistosomiasis, caused by Schistosoma mansoni, is a particularly concerning NTD that infects over 250 million people worldwide. While the current treatment with praziquantel is cost-effective, emerging drug resistance underscores the urgency for new therapeutic agents. Natural products, particularly medicinal plants like Copaifera oblongifolia, offer a promising source for novel drug discovery. Therefore, this study investigates the chemical composition of hexane fraction C. oblongifolia leaves. and its in vitro and in silico schistosomicidal activity. Through a series of extractions and gas chromatography-mass spectrometry (GC-MS) analysis, the n-hexane fraction contained triterpenes and steroids, which exhibited schistosomicidal activity against adult S. mansoni worms. The n-hexane fraction, particularly rich in these bioactive compounds, demonstrated 100% mortality at 100 µg/mL. In silico molecular docking was performed against S. mansoni thioredoxin glutathione reductase (TGR; PDB ID: 2XBI), a validated redox-regulating enzyme target. Among the identified compounds, β-amyrin showed the strongest binding affinity (- 7.4 kcal/mol, Ki: 3.7 μM), followed by lupeol (- 7.2 kcal/mol, Ki: 5.25 μM), both outperforming the reference drug praziquantel (- 6.5 kcal/mol, Ki: 7.34 μM). These findings indicate that C. oblongifolia contains compounds with promising antischistosomal activity. Further isolation, characterization, and in vivo studies are needed to confirm their potential as natural drug leads.

The online version contains supplementary material available at 10.1007/s40203-025-00501-7.