Efeitos in vitro e caracterização química dos óleos essenciais de Cinnamomum verum, Syzygium aromaticum, Origanun vulgare, Thymus vulgaris e seus componentes majoritários sobre Fascíola hepática

Abstract

The difficult control of fasciolosis has prompted researchers around the world to seek alternatives in order to prevent the spread of this disease. The aim of this study was to evaluate the in vitro action of the essential oils of Cinnamomum verum, Syzygium aromaticum, Origanum vulgare and Thymus vulgaris, as well as their respective main components eugenol, carvacrol and thymol on the motility of Fasciola hepatica. The trematodes were obtained in slaughterhouses in the southern of Espírito Santo and in the laboratory, incubated in solutions containing the above compounds at concentrations of 0.025% (m v-1), 0.05% (m v-1) and 0.1% (m v-1), and their motility recorded at 3 h, 12 h, 15 h and 24 h after incubation. The chromatographic analysis of essential oils revealed eugenol as the major compound of C. verum and S. aromaticum, while O. vulgare and T. vulgaris presented carvacrol as the main component. The images obtained by scanning electron microscopy of the specimens after 24 h incubation revealed the presence of significant tegumentary changes such as blebbing, loss of spines with hollow formation and extensive desquamation with basal lamina exposure. The highest number of alterations, which were also more severe, occurred in the concentration of 0.1% (m v-1) in all treatments, but in the essential oils of O. vulgare and T. vulgaris and components carvacrol and thymol, lesions also occurred at lower concentrations. The results obtained in the in vitro test demonstrated that essential oils and major components had a dose-dependent effect on the motility of F. hepatica, with a dose of 0.1% (m v-1) being the best treatment independent. Among the compounds tested, the essential oils of O. vulgare and T. vulgaris and the components carvacrol and thymol showed the best results in lower concentration and time.