Main compounds and in vitro effectiveness of Syzygium aromaticum essential oil on protoscoleces of hydatid cyst

Abstract

Surgery remains the preferred treatment for cystic echinococcosis. On the other hand, one of the side effects of hydatid cyst surgery is recurrence. Many scolicidal agents have been used for inactivation of the hydatid cyst content. However, many of these scolicidal agents may cause undesirable complications that limit their usage. The aims of this study are to investigate the chemical composition and in vitro scolicidal effect of S. aromaticum essential oil against protoscoleces from hydatid cysts of Echinococcus granulosus. The essential oil was obtained by hydrodistillation. Gas chromatography with flame ionization detection (GC-FID) and gas chromatography–mass spectrometry (GC/MS) was employed to determine the chemical composition of the essential oil. Protoscoleces were aseptically collected from infected organs (liver and lung) of animals slaughtered at the Tiaret slaughterhouse containing hydatid cysts. Protoscoleces were exposed to two concentrations of essential oil (10 and 15 μl/mL) for 5, 10, 15, and 20 min. Viability of protoscoleces was confirmed by 0.1% eosin staining. Eugenol was the major compound of the studied essential oil (78.72%) followed by β-caryophyllene (8.82%) and eugenyl acetate (8.74%). The scolicidal activity of S. aromaticum essential oil at the concentration of 10 μl/ml was 55.99%, 60.05%, 80.37%, and 99.76% after 5, 10, 15, and 20 min of exposure, respectively. S. aromaticum essential oil at the concentrations of 15 μl/ml killed 100% protoscoleces after 5 min of exposure. The present study confirmed that S. aromaticum essential oil has high scolicidal power in vitro. However, further studies (ex vivo and in vivo) will be needed to confirm these results.