Activity of Euterpe edulis Martius, Mikania glomerata Spreng, and Mikania laevigata Schultz Bip. Extracts on Gastrointestinal Nematodes Toxocara canis and Ancylostoma caninum

Background: Gastrointestinal parasitoses have high rates of morbidity and mortality. Each year about 3.5 billion people are affected by these diseases and 65,000 of them die, mostly in developing countries due to lack of basic sanitation, malnutrition, and poor access to medication. Thus, they constitute an important public health problem due to causing direct health problems related to lack of piped water, absence of sewage system, and lack of orientation. Objectives: Two in vitro assays were performed to evaluate the larvicidal and/or ovicidal activity of ethanol extracts obtained from the plants Euterpe edulis, Mikania laevigata, and Mikania glomerata on the gastrointestinal nematodes Toxocara canis and Ancylostoma caninum. Materials and Methods: In the first assay (A), T. canis eggs were exposed to three different concentrations (0.1 mg/mL, 1 mg/mL, and 10 mg/mL) of each extract, three different concentrations of albendazole (positive control), ethanol (solvent), and a negative control (no treatment), for 15 days at 26°C, under the shelter of light in order to evaluate the percentage of embryonated eggs in the presence of these extracts. In the second assay (B), the larvicidal activities of the species studied were evaluated in the different extract concentrations (0.1 mg/mL, 1 mg/mL, and 10 mg/mL), control, and solvent (ethanol), in coprocultures positive for A. caninum eggs. Results: In assay A, the results demonstrated inhibitory embryogenesis activity on T. canis eggs; however, no difference (P > 0.01) was found between the activities of the extracts. In the control group, there was a difference (P < 0.01) in relation to the tested extracts, in which this difference was not concentration-dependent. In assay B, all extracts showed inhibitory (P > 0.01) hatchability activity of A. caninum eggs in the control group. Conclusions: Through these results, the applicability of the used extracts in the control of eggs and/or larvae of T. canis and A. caninum is suggested. However, it is worth mentioning that further studies should be performed with the species E. edulis, M. glomerata and M. laevigata, using different extracts, new concentrations, and in vivo studies, in order to ensure further clarification on the agents responsible for the observed effects, degree of efficacy, and toxicity.