Composition, antioxidant and antimicrobial activities of cold-pressed and distilled essential oils of Origanum onites L. and Lavandula officinalis L. relationships evaluated by SEM microscopy

Summary Introduction: In order to prevent increased bacterial resistance, it is important to use herbal medicines with less side effects. Objective: In this study, the chemical composition, antimicrobial, antioxidant activities and SEM images of Lavandula officinalis and Origanum onites oils obtained in two different ways were determined. Methods: The antimicrobial activity of the oils was determined against reference and multiple strains of foodborne and pathogenic bacteria. The each essential oil sample were analyzed by GC–MS. Antioxidant activities of the samples were examined through DPPH• and ABTS•+ radical scavenging and FRAP assays. Results: The results indicate that the oils of obtained from Origanum onites and Lavandula officinalis exhibited relatively strong antibacterial and antifungal activity. In addition, the antioxidant activities detected were remarkable. Morphological changes in bacterial cells treated with essential oil samples were demon- strated with SEM images. In addition, the chemical components of the oil samples obtained by both water steam and cold press were revealed by GC-MS analysis and compared. Conclusion: When all the obtained results are evaluated together; these plants could be suitable for using as antimicrobial and antioxidative agents in several industries such as food, cosmetic, etc.