The effect of Spondias mombin L. against Strongyloides venezuelensis: An in vitro approach

Strongyloidiasis is a neglected tropical disease mainly caused by the nematode parasite Strongyloides stercoralis. Current treatment consists in the administration of ivermectin or, alternatively, albendazole (or analogues). Concerns regarding these drugs' irregular cure rates and side effects, raise a need for therapeutic alternatives. In this study, we tested the in vitro effect of Spondias mombin L. ethanolic extract against the laboratory model for strongyloidiasis, Strongyloides venezuelensis. The ethanolic extract was further fractionated and each fraction was also tested. Tested fractions were analyzed through thin layer chromatography and gas chromatography (GC/MS). Our results showed that S. mombin extract and fractions had a better in vitro effect than ivermectin, particularly fraction 4 which showed the better results causing 100% mortality in 4 h after exposure to an extract concentration of 400 µg/mL of RPMI medium and caused 100% mortality 12 h after exposure to an extract concentration of 50 µg/mL. Scanning electron microscopy showed that this fraction caused both wrinkling and peeling of the parasites cuticle, whilst ivermectin only caused wrinkling. GC/MS showed a high percentage of monoaromatic phenolic lipids (3-R phenol and 3-R1 phenol), which were likely responsible for the anti-Strongyloides effect. The use of polyvinylpyrrolidone reduced the efficiency, thus raising a need for alertness when using this excipient. Our results suggest that S. mombin is a potential source of compounds that could be used for stongyloidiasis treatment.