In vitro ovicidal and larvicidal activity of Carica papaya seed hexane extract against Strongyloides venezuelensis

Abstract

Strongyloidiasis is a human parasitic disease caused by the helminth Strongyloides stercoralis whose treatment is particularly difficult in immunosuppressed patients due to their low responsiveness to conventional therapy. Carica papaya and its isolated compounds benzyl isothiocyanate, carpaine and carpasemine are promising compound for the treatment of Strongyloides infections due to their anthelmintic action. This study aims to examine the in vitro ovicidal and larvicidal activity of C. papaya seed hexane extract against Strongyloides venezuelensis, using egg hatching tests and larval motility tests as efficiency markers. The crude extract at the concentrations of 566 – 0.0566 mg/mL or the control with albendazole (0.025 mg/mL) and negative controls (water and PBS) were incubated with an equal volume of egg suspension (± 50 specimens) followed by counting of the specimens after 48 h. The same extract and dilutions were added to L3 larvae suspensions (±50 specimens) followed by analysis of larvae viability after 24, 48, and 72 h. The extract inhibited egg hatching with high efficiency at concentrations of 56.6 mg/mL (95.74%) and 5.66 mg/mL (92.16%). At the concentrations of 566 mg/mL (100%) and 56.66 mg/mL (97.32%), the extract inhibited larval motility as effectively as ivermectin (0.316 mg/mL; 100%), and more effectively than the other dilutions and the negative controls. The larvicidal effect depended on the extract concentration, but not on the treatment period. Therefore, C. papaya seed hexane extract has anthelmintic potential against S. venezuelensis and is a promising compound for the development of phytotherapies to treat strongyloidiasis.

Nematicidal activity of aqueous tinctures of plants against larvae of the nematode Strongyloides papillosus

“…Ismail et al (2016) determined anthelmintic properties of Lawsonia inermis L. against larvae of Strongyloides spp. Moraes et al (2017) and Cabral et al (2019) studied the impact of some constituents of Carica papaya L. on eggs and larvae of Strongyloides venezuelensis (Brumpt, 1934). Extract of Siparuna guianensis Aublet also exhibited high anthelmintic activity (Carvalho et al, 2019) towards eggs and larvae of S. venezuelensis Brumpt, 1934.…”