Essential oils (EO) were isolated by steam-distillation from fresh peel of citrus aurantium grown in Eastern Morocco and harvested in February (EO1) or December (EO2). EO were also isolated from peel of citrus aurantium harvested in December and dried at 25°C (EO3) or 50°C (EO4). Soxhlet hexane extract from dried peel of citrus aurantium was also used to isolate EO by steam-distillation (EO5). All these EO were analyzed by gas chromatography (GC) coupled to mass spectrometry (GC–MS). Variation in the yield and chemical composition of these essential oils were determined. Less than nine components were identified and constituting approximately 96 to 100% of the oil. The major component always was limonene for all EO. The antioxidant activity of these EO has been evaluated using in vitro DPPH assay and the results were compared with standard antioxidant(ascorbic acid). The effect of these EO on the growth rate of the yeast Saccharomyces Cerevisiae, gram-negative bacteria (Escherichia coli DH5α and Citrobacter freundii) and gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus)was studied. Ours findings fromcitrus aurantium peel EO possess very weak antioxidant activity. In contrast, it showed significant antifungal activity and variable antimicrobial activity.
