Abstract

The essential oils and defatted ethanolic extracts isolated from Cupressus sempervirens L. leaves collected from two geographically distinct regions in Lebanon; Beit El-Dein (mountain) and Jbeil (sea-side) were analysed for their chemical composition by GC/MS and qualitative phytochemical screening, respectively. These were then tested for their in-vitro antioxidant and antibacterial activities. Fourteen and eighteen compounds were identified in Beit El-Dein and Jbeil samples, respectively with α-pinene (45.69-20.97%) and δ-3-carene (24.55-16.7%) representing the major constituents. C. sempervirens L. ethanolic extracts were able to reduce the stable radical 1,1-Diphenyl-2-picrylhydrazyl (DPPH) reaching 50% reduction with IC50 values equal to 113.17 and 155.75 μg/ml, respectively. These results positively correlated with the high phenol (77.4-66.4 mg gallic acid equivalent/g dry weight) and flavonoid (3.8-2.8 mg rutin equivalent/g dry weight) contents in both samples, respectively. Regarding the in-vitro antibacterial activity, essential oils exhibited a stronger potential mainly towards the Gram-positive bacteria Staphylococcus aureus compared with the ethanolic extracts as this was revealed by higher diameters of inhibition zone ranging between 7 and 12.3 mm and minimal inhibitory concentrations equal to 15.62 μl/ml. The results obtained from this study show that the Lebanese Cypress may be used as a good source of natural food preservatives and as drugs for various ailments.

Key words: Lebanese Cupressus sempervirens L., essential oil and ethanolic extract, antioxidant, antibacterial activities.