In Vitro Study of the Antiparasitic Activity of Vitellaria paradoxa Gaertn (Sapotaceae) on the Parasite Onchocerca ochengi

Onchocerciasis is a parasitic disease that affects millions of animals and people around the world. A recipe based on Vitellaria paradoxa is used in traditional medicine against this disease in Chad. The objective of this study was to evaluate the antiparasitic activities of extracts from the roots, fruits, leaves and bark of Vitellaria paradoxa on the parasitic nematode Onchocerca ochengi, a model similar to Onchocerca volvulus used in the research of control drugs. against onchocerciasis. The identification of parasites and the hydroethanolic extracts of the different planar organs were carried out at the Laboratory of Research, Diagnostics and Scientific Expertise (LaboReDES) of the Faculty of Human Sciences, University of N'Djamena using the methods of Ndjonka et al., 2012. The extracts of this plant were tested at different concentrations (0.1; 0.2; 0.3; 0.4 mg/mL) in the RPMI-1640 culture medium. The antiparasitic activity was noted according to the mortality rate after 72 hours of incubation of Onchocerca ochengi at 37°C. The LC50 values were then graphically determined at the end of this incubation. They were 0.05 mg/mL for the roots; 0.06 mg/mL for fruits; 0.05 mg/mL for the leaves and 0.06 mg/mL for the bark. These results confirm the effectiveness of Vitellaria paradoxa used in traditional medicine to treat parasitosis. This plant also has the same effects as ivermectin. The V. paradoxa root test on microfilariae shows an LC50 value of 0.05 mg/mL in 24 hours of incubation. This study showed that the hydroethanolic extracts of the bark of Vitellaria paradoxa had antiparasitic activities, allowing the development of a new molecule active against these parasitic infections and also the extracts of this plant could be used as alternatives to treat infections in case of parasite resistance to ivermectin.