Osmanthus fragrans essential oil: GC-MS chemical composition, antimicrobial, antibiofilm, and insecticidal properties
Abstract
Natural and sustainable solutions for food preservation are increasingly focusing on essential oils as promising agents with potent antimicrobial, antibiofilm, and insecticidal properties. The aim of this study was to evaluate the chemical composition of Osmanthus fragrans essential oil (OFEO), its antimicrobial activity against various Gram-positive and Gram-negative bacteria and yeasts including the biofilm-forming strain Salmonella enterica , its effects on biofilms analyzed by MALDI-TOF MS spectral profiling, and its insecticidal activity against Megabruchidius dorsalis . GC–MS analysis revealed that OFEO predominantly contains trans-β -ionone (24.1%), linalool (18.0%), and 2(3H)-furanone (9.0%), compounds known for their antimicrobial and antibiofilm effects. OFEO exhibited significant antimicrobial activity with minimum inhibitory concentrations (MIC₅₀) ranging from 0.072 to 3.16 mg/mL, while the biofilm-forming Salmonella enterica showed greater tolerance. In situ vapor-phase tests on fresh fruits and vegetables (apple, peach, beetroot, carrot) demonstrated matrix- and concentration-dependent inhibition of microbial growth. MALDI-TOF MS comparison revealed differences in mass spectral profiles of biofilms after OFEO treatment, indicating disruption of biological processes essential for biofilm structure and function. Additionally, OFEO demonstrated potent insecticidal activity against Megabruchidius dorsalis , with 100% mortality observed at full concentration and significant mortality at lower doses. These results support the potential of OFEO as a natural antimicrobial, antibiofilm, and insecticidal agent suitable for improving food safety, extending shelf life, and managing pests in the food industry. GC-MS identified 27 volatiles defining O. fragrans essential oil composition . O. fragrans oil inhibited pathogens and reduced Salmonella biofilm formation . O. fragrans oil showed strong insecticidal effect on Megabruchidius dorsalis.