Atividade ovicida in vitro do óleo de Helianthus annuus L. e Cuminum cyminum L. sobre Fasciola hepática (Linnaeus, 1758)

Abstract

The trematode Fasciola hepatica is responsible for high economic losses to Brazilian and world livestock. It affects mammals in general, but cattle, sheep and goats are the main definitive hosts and it can accidentally infect humans. The most commonly used form of control has been through synthetic anthelmintic, which has been shown resistance and adding to it there is the possibility residues of these agents in products such as meat and milk, which has become a worldwide concern. The search for alternatives as plant derived products with biological activity in the control of parasites has shown promise with the possibility to inhibit them at some stages of its life cycle. In view of this, this study aimed to evaluate the ovicidal activity in vitro of fixed oil of Helianthus annuus L. (OFH) and essential oil of Cuminum cyminum L. (OEC) and the possible synergism between OFH and OEC on F. hepatica eggs and their cytotoxicity. The evaluate chemical composition and the ovicidal activity was evaluated in vitro by development and larval hatchability. For this, adult forms of F. hepatica were obtained from the infected livers for obtaining eggs which were exposed to concentrations of 0.25% to 0.0005% for each of the oils evaluated. The assay was accompanied by a negative control (water) and a positive control (Thiabendazole 0.025mg/ml). The identification of the major chemical compounds was performed by gas chromatography. The cytotoxicity of the oils was tested on lineage MDBK cells (Madin-Darby-Bovine Kidney) by MTT method. Were identified as the major compounds of OFH the unsaturated fatty acids linoleic (53.6%), and oleic (35.85%), and photochemical major compounds of OEC were Cumaldehyde (26.8%) and 2-Caren 10-al (22.17%). The OEC at a concentration of 0.03 mg/ml and the combination of OFH + OEC at a concentration of 0.035 mg/ml + 0.03 mg/ml showed efficacy of 99% (± 1) and 98% (± 1) respectively, and OFH was insufficiently active as ovicidal. At these concentrations cell viability was 93% and 85% respectively and also in the concentration of 0.015mg/ml OEC was 97% effective, and preserved 99% of viable cells. Given the above it can be inferred that OEC may be promising as a new alternative in the control of fascioliasis.