Identification of the chemical compounds, antioxidant potential, antifungal activity on some fungal strains causing strawberry’s rot

Microbial contamination and spoilage caused by pathogenic microorganisms cause irreparable damage to fruit and vegetable producers annually. For this reason, chemical pesticides are used to prevent the growth of spoilage microorganisms in vegetables and fruits, which has caused problems such as environmental pollution, human poisoning, high costs, and the development of resistant microorganisms. Today, plant essential oils are one of the most important natural compounds used to control fungal contamination. The aim of this study was to investigate the chemical composition of Origanum vulgare essential oil, its phenol and total flavonoid content, antioxidant activity and antifungal effect on Rhizopus stolonifer, Aspergillus niger, and Botrytis cinerea. In this study, the essential oil of Origanum vulgare was extracted by hydrodistillation method and its main chemical compounds, total phenol and flavonoid contents, antioxidant activity, and antifungal effect against strawberry’ rot species (Rhizopus stolonifer, Aspergillus niger, and Botrytis cinerea) were investigated. Among 19 identified compounds (96.49% of the total essential oil compounds), carvacrol (29.15%) and linalyl acetate (22.25%) were the main chemical compounds in the essential oil, respectively. Also, the total phenol content of the essential oil was 48.38 ± 0.26 mg GAE/g and the total flavonoid content was found to be 36.26 ± 0.52 mg QE /g. DPPH free radical scavenging effect (IC50), ABTS free radical scavenging activity (IC50), and β-carotene/linoleic acid bleaching inhibitory effect were 24.27 ± 0.39 μg/ml, 19.15 ± 0.22 μg/ml, and 59.65± 0.62%, respectively. Antifungal effect results (disk diffusion agar, well diffusion agar, minimum inhibitory concentration, minimum fungicidal concentration) showed that A. niger and B. cinerea were the most sensitive and resistant strains to the essential oil, respectively. Due to its high antioxidant and antifungal properties, O. vulgare essential oil can be used as a natural antimicrobial and antioxidant compound.