The present study was designed to evaluate commercial cedar essential oil (CEO), obtained by hydrodistillation from cedar wood, in relationship to its chemical composition and antioxidant, in vitro and in situ antimicrobial, antibiofilm, and anti-insect activity. For these purposes, gas chromatography-mass spectrometry, DPPH radical-scavenging assay, agar and disc diffusion, and vapor phase methods were used. The results from the volatile profile determination showed that δ-cadinene (36.3%), (Z)-β-farnesene (13.8%), viridiflorol (7.3%), and himachala-2,4-diene (5.4%) were the major components of the EO chemical constitution. Based on the obtained results, a strong antioxidant effect (81.1%) of the CEO was found. CEO is characterized by diversified antimicrobial activity, and the zones of inhibition ranged from 7.33 to 21.36 mm in gram-positive and gram-negative bacteria, and from 5.44 to 13.67 mm in yeasts and fungi. The lowest values of minimal inhibition concentration (MIC) were noted against gram-positive Micrococcus luteus (7.46 µL/mL) and against yeast Candida krusei (9.46 µL/mL). It seems that the vapor phase of CEO can inhibit the growth of the microscopic filamentous fungi of the genus Penicillium according to in situ antifungal analysis on bread, carrots, and celery. This finding confirms the impact of CEO on the change in the protein structure of older biofilms of Pseudomonas fluorescens and Salmonella enterica subsp. enterica. Insecticidal activity of a vapor phase has also been demonstrated against Pyrrhocoris apterus. CEO showed various advantages on antimicrobial activity, and it is an ideal substitute for food safety.
Keywords: antibiofilm activity; antimicrobial activity; atlas cedar; essential oil; repellent activity; vapor phase.