The antioxidant properties of essential oils are very little studied. Oxidative stress occurs when the imbalance between the production of free radicals and antioxidant enzymes is related to the onset of serious diseases. The antioxidant activity of the essential oil of Nigella sativa against the DPPH radical has been evaluated by spectrophotometry. The results show an antioxidant power with an IC50 of 0.056 mg/ml. This activity is mainly due to the combined action of various endogenous antioxidants contained in the essential oil. The study of the acute toxicity of the essential oil of Nigella sativa showed no mortality in groups of used animals. The work of [1] confirms our results. However, the author of [2] found a toxicity of this essential oil, due, according to him, to the presence of thymoquinone.
