Prospecção dos óleos essenciais da família Lamiaceae, sobre ovos de Ancylostoma spp.

Abstract

The hookworms are parasites that contaminate the environment and determine, in animals and humans, parasitic infections of public health importance. The prevalence of zoonotic hookworms is elevated in the south of Rio Grande do Sul and, added to this, some pets endoparasites are resistant to certain anthelmintic. Thus, the work aimed to evaluate the anthelmintic activity, in vitro, of essential oils of the Lamiaceae family compared to Ancylostoma spp. eggs obtained from naturally infected dogs as well as to assess the chemical composition of essential oils. For such, larval hatchability tests were performed, where the eggs of the parasite were exposed to concentrations of 2.5% to 0.07% of essential oils of Origanum vulgare (oregano), Origanum majorana (marjoram) and Rosmarinus officinalis (rosemary). The test was followed by a positive control containing thiabendazole hydrochloride (0.025 mg/mL), a negative control with distilled water and the control with tween 80. The chemical composition of each sample of the essential oils was determined by gas chromatography attached to the mass spectrometer (GC-MS). It was observed that all essential oils have shown anthelmintic activity and it was noticed that the percentage of hatchability inhibition of rosemary oil was of 100% in the concentration of 12,5%, higher than 90% in the concentrations of 7,5mg/ml and 3,1mg/ml, as wel as, higher than 50% in the concentration of 1,55mg/ml, although it was lower than it in the concentrations of 0,75mg/ml and 0,35mg/ml. Regarding to the oregano essential oils, the concentrations of 10mg/ml, 5mg/ml and 2,48mg/ml have presented an inhibitory percentage of 100%, while the concentration of 1,24mg/ml has presented a value higher than 90% and it was higher than 50% in the concentration of 0,6mg/ml. However, the percentage was lower than it in 0,28mg/ml. On another hand, the marjoram essential oil has presented 100% of hatchability inhibition in the concentrations of 15mg/ml, 7,5mg/ml and 3,72mg/ml, higher than 90% 1,86mg/ml, higher than 50% in 0,9mg/ml and lower than it in 0,42mg/ml of concentration. The major chemical compounds for the O. vulgare were 4-terpineol (27.24%), thymol (19.78%) and gamma terpinene (14.23%), while for the O. majorana essential oil, 4-terpineol (35.99%), gamma terpinene (16.76%) and alpha-terpinene (11.43%) were identified and, for the R. officinalis oil, cineole (42.12%), camphor (16.37%) and alpha-pinene (14.76%) were observed as major components. According to the results, it can be stated that, under the test conditions, the R. officinalis, O. vulgare and O. majorana essential oils have activity in the hatchability inhibition of Ancylostoma spp eggs, what can be a promising alternative for controlling this parasitosis, being further studies necessary.