Abstract:To study the components and in vitro antibacterial and anti-inflammatory activities of essential oils from Cedrus atlantica.Gas chromatography-mass spectrometry（GC-MS）was performed to analyze the essential oils，and peak area normalization method was used to calculate the relative content. Oxford cup method was employed to determine the antibacterial effect of the essential oils on Staphylococcus aureus，Escherichia coli and Candida albicans. Then an LPS-induced RAW264.7 inflammation model was established to determine the content of tumor necrosis factor-α（TNF-α）in the cell supernatant.Thirty peaks were detected by GC-MS，and 18 compounds were identified，accounting for 87.58% of the total peak area.Among them，terpenes accounted for 83.26%，of which（+）-aromadendrene（31.56%），longicyclene（20.29%）and（-）-α-gurjunene（12.90%）had higher content. C. atlantica essential oils had certain antibacterial effects on S. aureus，E. coli，and C.albicans.Moreover，the expression of iNOS mRNA in RAW264.7 cells was markedly inhibited at a safe concentration of the essential oils，and the mRNA expression of TNF-α and the secretion of TNF-α in supernatant were significantly affected. C. atlantica essential oils had certain antibacterial activities and can inhibit oxidative stress and inflammation-related enzyme iNOS，and GC-MS was a fast and convenient method for quality analysis of the essential oils.