Abstract

Since reactive oxygen species (ROS) play an important role in the pathogenesis of many human diseases, attention is given to the development of safe and effective natural antioxidants. In the present study, the protective and antioxidant potential of the argan oil extracted from the fruit of Argania spinosa, an endemic tree in Morocco, was evaluated against hydrogen peroxide (H₂O₂) induced oxidative damages in Tetrahymena pyriformis. The protozoan cells were cultivated in polypeptone yeast glucose (PPYG) medium supplemented with argan oil (AO) at a dose of 0.5% (v/v) during 4 subcultures and treated with different concentrations of H₂O₂. The effect of this oil on the protozoan growth was followed and the antioxidant enzyme activities of catalase (CAT), superoxyde dismutase (SOD) and glutathione reductase (GR) were evaluated as well as lipid peroxydation (MDA). As compared to the controls, the AO increased both the cell viability and the antioxidant enzyme activities and decreased the MDA level. The co incubation of T. pyriformis with AO and H₂O₂ (300 µM) reduced the H₂O₂ cytotoxicity. The cells cultivated in the presence of AO then exposed to H₂O₂ for 3 h, show a significant reduction in MDA level (p < 0.001), an important increase in CAT (p < 0.05) and SOD (p < 0.01) activities. No effect was observed in that GR activity. These results strongly indicate that AO have a protective potential against induced H₂O₂ cell damages. This protective effect may be due to antioxidant compounds present in high concentrations in the argan oil.

Keys words: Antioxidant enzymes, argan oil, hydrogen peroxide, lipid peroxidation,Tetrahymena pyriformis.