Anotace:
The essential oil obtained by microwave-assisted hydro-distillation (MAHD) and hydrodistillation (HD) techniques from the peel of grapefruit (Citrus paradisi. L) from Algeria was analysed by gas chromatography–flame ionization detector (GC–FID) and gas chromatography ⁄ mass spectrometry (GC⁄ MS). Twenty-one constituents were identified in essential oils obtained by HD and twenty-eight constituents in essential oils by MAHD, representing respectively 99.11% and 99.74% of the total oil. The main constituents were limonene (85.54%-87.51%) for MAHD and HD, β-myrcene (2.99%-3.24%), nootkatone (1.78%-1.80%). The antimicrobial activity of the essential oils was evaluated by disc diffusion method. The results showed interested inhibition growth against the tested bacteria (Escherichia coli, Pseudomonas aeruginos, and Staphylococcus aureus)and the yeast (Candida albicans),with an inhibition zone ranging from 4 to 20 mm.Both essentials oils showed no effect against Aspergilusniger, Verticillium sp and Thielaviopsis sp. The insecticidal activity was investigated against adults ceratitis capitata. Both essential oils showed a toxic effect against this insect (LD50:9.12µl EO/ml of acetone; LD90: 13.18 µl EO/ml of acetone).