Ovicidal and Larvicidal Activities of Saba senegalensis (A.DC) Pichon (Apocynaceae) Extracts and Fractions on Heligmosomoides bakeri (Nematoda, Heligmosomatidae)

Aims: To investigate ovicidal and larvicidal activities of an aqueous decoction (AD) and hydroethanolic macerate (HEM) extracts and fractions of the leaves of Saba senegalensis. Study Design: In vitro, the ovicidal and larvicidal activities of AD and HEM extracts and fractions of the leaves of Saba senegalensis on the eggs and larvae (L1) of Heligmosomoides bakeri. Place and Duration of Study: The experiment was conducted at the department of Medicine and Traditional Pharmacopeia-Pharmacy (MEPHATRA-PH) of Institute of Research in Health Sciences (IRSS) between June 2015 and December 2016. Methodology: The phytochemical groups of the extract and fractions of Saba senegalensis were determined by a colorimetric and Thin Layer Chromatography methods. The eggs were obtained from feces of mice deliberately infected and the larvae from the eggs were incubated at 25 ±2℃ for 72 hours. Eggs and larvae were exposed to increasing concentrations (100; 625; 1250; 2500; 3750 µg/mL) of the different extracts, 48 hours and 24 hours for the eggs and larvae respectively. Distilled water and DMSO 0.1% were used as negative controls while albendazole and levamisole were used as positive controls. Results: The phytochemical groups of interest are the tannins, saponins, flavonoids and triterpenes. The negative control had given 2.16% of egg hatch inhibition and 0% of larvae mortality mean while the positive control had given 100% in both cases. The extracts inhibited eggs hatching and affected larval survival. Pharmacological effects were concentration-dependent. The ovicidal and larvicidal activity of HEM is more interesting than that of AD with an Emax = 95.60% and an IC50 = 390 µg/mL. It is the same for the larvicidal activity with Emax = 100% and an LC50 = 900 µg/mL.  However, the differences were not statistically significant. Conclusion: These results show the ovicidal and larvicidal properties of the S. senegalensis leaves.