Biological Activity of Cupressus sempervirens Essential Oil

BACKGROUND

Essential oils are complex mixtures with potential antimicrobial, antioxidant, and other biological activities. This study aimed to evaluate the biological activities of Cupressus sempervirens essential oil (CSEO), including its potential as a natural preservative and anti-biofilm agent. Methods: The chemical composition of CSEO was analyzed by GC/MS. Antioxidant activity was assessed via DPPH and ABTS assays. Antimicrobial activity was tested in vitro using disc diffusion and minimum inhibitory concentration (MIC) methods against various bacteria, yeasts, and fungi. An in situ assay using kohlrabi as a food model evaluated vapor-phase antimicrobial activity. Antibiofilm activity against Salmonella enterica on stainless steel and plastic surfaces was analyzed using MALDI-TOF MS Biotyper. Insecticidal activity was tested against Oxycarenus lavaterae. Antiproliferative effects on human cancer cell lines (MDA-MB-231, HCT-116, JEG-3, K562) and a normal fibroblast line (MRC-5) were evaluated via MTT assay. It demonstrated strong antioxidant activity, with 10 μL neutralizing 76.32 ± 0.43% of DPPH radical and 91.53 ± 0.16% of ABTS radical cation. Antimicrobial activity varied; strong effects were noted against Bacillus subtilis and Candida albicans in disc diffusion. MIC50 values ranged from 40.92 to 374.02 µL/mL. In situ vapor-phase activity was generally more effective at lower concentrations, except for S. enterica biofilm, which showed growth stimulation at higher concentrations. MALDI-TOF MS analysis indicated CSEO significantly disrupted S. enterica biofilm homeostasis from day 7 onwards. Insecticidal activity against O. lavaterae was concentration-dependent, with LC50 at 21.07% and LC90 at 78.21%. CSEO induced time- and dose-dependent antiproliferative effects on cancer cells, with K562 cells being most sensitive (IC50 of 105.06 µg/mL at 24 h and 66.56 µg/mL at 72 h), while showing acceptable biocompatibility with MRC-5 cells (>80.25% viability at 200 µg/mL). Limitations: The study is entirely preclinical, using in vitro and in situ models without human participants. The clinical significance of the antiproliferative effects is not established, and further testing is needed. Implications: The findings suggest CSEO has potential applications in food preservation, as an anti-biofilm agent, and in agricultural pest control. Its antiproliferative activity warrants further investigation, particularly for chronic myelogenous leukemia, but these results are preliminary and not directly translatable to human therapy.