Investigating the antifungal mechanism of Artemisia argyi essential oil against Botrytis cinerea, Alternaria alternata, and Penicillium digitatum and its application in extending blueberry shelf life

Abstract

The trend towards reducing chemical fungicides in the food industry has increased interest in antimicrobial essential oils for food preservation. This study investigates the chemical composition of Artemisia argyi essential oil (AAEO) and its efficacy in inhibiting Botrytis cinerea, Alternaria alternata, and Penicillium digitatum, along with potential antifungal mechanisms involved. GC–MS analysis identified that the main components of AAEO were eucalyptol (19.19 %), L(−)-borneol (6.38 %), camphor (6.17 %), (+)-thujone (5.74 %), terpinen-4-ol (5.55 %), and p-cymene (5.31 %). AAEO demonstrated significant antifungal activity against all three fungi, especially through non-contact exposure. Exposure to AAEO increased AKP, nucleic acid and soluble proteins release, reflecting cell wall and membrane integrity alterations. AAEO also reduced biofilm formation, cell viability, and respiratory activity. SEM images revealed cellular fractures and deformations in the fungal cell walls. The fumigation with AAEO during storage resulted in a significant reduction of both the decay rate (by 24.7 %) and pathogen infestation (by 61.2 %) in blueberries on the 13th day of storage. A 50.8 % reduction in Alternaria alternata incidence was observed in inoculated blueberries by day 4 post-AAEO treatment. Therefore, AAEO is a potent antifungal agent against B. cinerea, A. alternata, and P. digitatum, positioning it a promising option for food preservation.